culture

Borrelia burgdorferi genotypic diversity, pathogenesis, and host cellular responses

PROJECT SUMMARY Lyme disease is the most common tick-borne illness in the United States, with an estimated 476,000 cases annually, and Pennsylvania (PA) consistently reports one of the highest case numbers nationwide. Borrelia burgdorferi sensu stricto (Bb) is a causative agent of Lyme disease in the US and is transmitted by Ixodes spp. ticks. Bb produces various outer surface proteins (Osp) and other mechanisms to survive in vectors, evade host immune systems, and to propagate infection within a host. Over 35 OspC genotypes have been characterized, which fluctuate in abundance in natural vector and host populations, suggesting host adaptation. While many Lyme-infected patients recover following antibiotic treatment, some may experience neurological symptoms, Lyme neuroborreliosis (LNB), which may be associated with specific genotypes. While previous studies focused on clinical manifestations, pathogenicity, genetic variations, and host immune responses using mouse models or patient samples, the genotype-specific immune responses that contribute to disease progression in humans remain poorly understood. Our central hypothesis is that certain Bb OspC genotypes, maintained in natural populations, are associated with distinct host immune responses that influence disease severity, progression, and persistence. Aim 1 will define the dynamics of OspC genotypes in tick and small mammal populations over time in Western PA to establish a 16-year longitudinal tick study and an 8-year longitudinal small mammal study. Using deep amplicon sequencing, we will quantify genotype diversity, detect low-abundance genotypes, and identify potential host-adapted genotypes. These empirical data will inform a compartmental mathematical model to evaluate OspC genotype prevalence, distribution, and public health risks, including LNB, across space and time. Aim 2 will assess how distinct Bb OspC genotypes affect the host immune landscape and cellular responses using human samples. To determine how Bb genotype contributes to disease phenotype, we will perform immune profiling studies which will include microscopy-based assessment of infected cell cultures, flow cytometric analysis of immune cell phenotypes, and measurement of genotype-specific cytokine, chemokine, and antigen production (sub-Aim2a). We will also employ multi-omics approaches that integrate single cell RNA sequencing with antibody-based protein profiling (scRNA-seq/Ab-seq) to characterize transcriptional and functional changes in immune cell populations exposed to different Bb genotypes (sub-Aim2b). This work is innovative in its integration of long-term ecological data with advanced immune profiling and single cell multi- omics to uncover genotype-specific mechanisms of Bb pathogenicity and human immune response—an approach not previously applied in Lyme disease research. These studies will clarify how specific genotypes influence immune responses and disease severity. Together, the proposed aims will identify critical genetic and immunological mechanisms that drive Bb pathogenicity and human susceptibility, informing the development of improved diagnostics, targeted therapies, and public health interventions to reduce the burden of Lyme disease.

TACTIC: Tuberculosis Active Case Tracking via Interpersonal Connections

PROJECT SUMMARY/ABSTRACT Tuberculosis (TB) remains the leading infectious cause of death worldwide. Interruption of transmission is the most effective strategy to reduce incident infections, yet current approaches often fail to reach individuals for timely testing and treatment. This study addresses that gap by leveraging social networks to identify individuals at highest risk of transmitting TB, specifically, people who use drugs (PWUD). We will evaluate respondent-driven sampling (RDS), a peer7 based community recruitment strategy, to identify TB cases among PWUD and the household contacts (HHCs) of those with TB disease (RDS-TB) in Kampala, Uganda. Conducting this work in a high-prevalence setting such as Kampala where our team has established expertise allows us to overcome recruitment challenges common in settings in the United States while generating findings that are directly translatable. This is particularly relevant given that higher TB prevalence and larger outbreaks in the United States have been associated with the use of methamphetamine, heroin, and crack/cocaine, drugs that we will study. In Aim 1, we will compare the effectiveness and reach of RDS-TB with a traditional clinic-based index case HHC approach for TB case finding. We will screen 2,000 PWUD and their HHCs, estimate the number needed to screen to identify one case of TB disease, and compare the demographic and network characteristics of RDS-TB recruits with clinic-based HHCs. Whole genome sequencing will be used to characterize transmission dynamics. In Aim 2, we will compare the yield of individual and combined TB diagnostic strategies for community-based active case finding. Participants will undergo chest radiography with computer-aided detection, tongue swab testing for TB nucleic acid amplification tests (NAAT), and sputum testing for NAAT and mycobacterial culture. We will identify the minimal combination of tests needed to meet World Health Organization target product profile thresholds for screening. In Aim 3, we will define the conditions under which RDS-based screening can effectively interrupt TB transmission. We will develop an agent-based model informed by social network data from individuals with and without TB, incorporating drug use patterns and demographic characteristics. This project will generate a practical, scalable roadmap for social network–based TB active case finding in high28 risk communities. The approach will be readily adaptable to settings in the United States and will inform strategies to interrupt transmission and advance progress toward TB elimination, in alignment with the NIH Strategic Plan for TB Research.

FIRE-PF: Developing and Testing a Trauma-Informed Alcohol Intervention to Enhance Mental Health in Firefighters

PROJECT SUMMARY Alcohol use and hazardous drinking are ubiquitous among firefighters in the United states and is associated with significant physical and mental health risks for this population. Due to the nature of their work, firefighters experience substantially higher rates of trauma exposure and are subsequently at greater risk of developing specific mental health conditions compared to the general population, particularly trauma-related psychopathology (e.g., posttraumatic stress). Hazardous drinking and posttraumatic stress frequently co-occur among firefighters, leading to poorer health outcomes compared to either condition alone. Despite this elevated risk, firefighters often lack access to tailored, empirically supported interventions, and no existing mental health interventions address hazardous drinking in a trauma-informed framework for this at-risk population. Personalized feedback interventions (PFIs) are a promising approach that could address this gap. By delivering brief, patient-centered feedback on drinking behaviors and perceptions within the context of trauma and occupational stress, PFIs aim to reduce problematic drinking behaviors and stigma related to coping-orientated drinking and improve stress management strategies. PFIs can be brief, cost-effective, and easily disseminated in a format accessible to large groups, making them a strong candidate for use with firefighters who face critical barriers to engaging in traditional mental health programs. This innovative study aims to develop a single-session, trauma-informed, online PFI tailored specifically for firefighters, using a comprehensive, three-phase approach to address three primary aims. The Development Phase involves developing, adapting, and enhancing a trauma-informed PFI by gathering qualitative feedback from firefighters (N = 45) and using an iterative, rapid user-centered design approach to ensure the intervention is engaging for firefighters as well as relevant and aligned with fire service culture. The Evaluation Phase will assess the feasibility, acceptability, and preliminary impact of the PFI in a mixed-methods longitudinal open trial with firefighters (N = 50), with a focus on the intervention's usability, delivery, and influence on drinking behaviors. The Implementation Planning Phase will involve qualitative and quantitative assessments with fire service leaders (N = 15) to identify implementation barriers and shape future research testing the implementation process for the intervention and inform future strategies for resource integration and fostering sustainable community partnerships. This proposal will equip Dr. Lebeaut with essential training for an independent research career, including training in (1) qualitative methodologies, (2) user-centered design, (3) developing, adapting, and enhancing trauma-informed alcohol interventions, and (4) developing collaborative relationships with community partners in the fire service. The proposed study will directly inform a future R01 to evaluate the intervention’s efficacy and scalability and support the development of a firefighter-focused research program.

Delineating the role of TREM2 in chronic pancreatitis

PROJECT SUMMARY Chronic pancreatitis (CP) is a progressive digestive disorder characterized by persistent inflammation, irreversible fibrosis, and acinar cell damage. However, current treatment options remain limited, underscoring the need for effective, targeted therapeutic strategies through a deeper understanding of the disease microenvironment. Macrophages are pivotal players in the CP microenvironment, exhibiting dual roles in inflammation and tissue remodeling. A defining feature of macrophages is their remarkable phenotypic plasticity, enabling them to transition between pro-inflammatory and anti-inflammatory phenotypes. However, the specific macrophage phenotypes contributing to the immune imbalance in CP and their precise mechanisms of action remain poorly understood. TREM2 (Triggering Receptor Expressed on Myeloid cells 2), a transmembrane receptor of the immunoglobulin superfamily, has emerged as a critical modulator of tissue damage responses in multiple disease settings, though its function in CP remains unexplored. Our preliminary single-cell RNA-seq analyses of human CP tissues reveal an enrichment of inflammatory macrophages alongside a marked downregulation of TREM2 compared to non-diseased controls. This reduction in TREM2 correlates with marked increases in pro-inflammatory mediators, such as IL-1β and NF-κB, suggesting that TREM2 in macrophages contributes to maintaining homeostasis and restraining inflammatory signaling. Accordingly, diminished TREM2 expression appears to skew macrophages toward a pathologically hyper-inflammatory state. We hypothesize that loss of TREM2 disrupts the delicate balance among immune cells, fibroblasts, and acinar cells, fueling a self-reinforcing cycle of inflammation and fibrosis that exacerbates pancreatitis. To test this hypothesis, our R01 will leverage integrative single-cell transcriptomics, spatially resolved imaging, transgenic mouse models, functional organoid co-culture assays, and in vivo experiments to elucidate TREM2’s regulatory mechanisms in CP. This research aims to address two key scientific questions: (1) How does TREM2 suppress pro-inflammatory macrophage phenotypes and restrain IL-1β-induced inflammatory signaling? (2) How does the crosstalk among pro-inflammatory macrophages, fibroblasts, and acinar cells exacerbate the local inflammatory environment, leading to further pancreatic damage? Through this study, we aim to establish TREM2 as a pivotal inhibitory checkpoint in the NF-κB/NLRP3/IL-1β axis, preventing unchecked macrophage-driven inflammation, fibroblast activation, and further acinar cell damage. Successful completion of this project will deepen our mechanistic understanding of CP and identify new therapeutic strategies to mitigate fibrotic progression and preserve pancreatic function. Ultimately, these insights may guide the development of immunomodulatory treatments to attenuate CP severity, thereby transforming the clinical management of this devastating disorder.

Role of cellular physical interactions in pancreatic cancer progression

Pancreatic cancer, with a 5-year overall survival rate of 13%, has the lowest survival rate of all cancers. The goal of this project is to better understand the biological processes of pancreatic cancer progression and discover their potential as targets for efficient therapies. Pancreatic ductal adenocarcinoma (PDAC) underdoes epithelial architecture changes during its progression. However, the underlying mechanisms for these changes are largely unknown. Interestingly, our recent data demonstrate the recapitulation of the distinct epithelial architectures in the organoid culture of cells derived from the human normal pancreas, primary tumor, and metastatic lesions, thereby developing a unique organoid model for the in vitro studies of PDAC epithelial architecture changes. The primary objective of this project is to understand the regulation of the differential PDAC epithelial architectures as well as their contribution to PDAC progression. Our central hypothesis is that disruption in lumen structure drives PDAC epithelial architecture transition and promotes PDAC progression. We will combine experimental and computational approaches to test our central hypothesis by pursuing the following two specific aims: (Aim 1) define the regulators of PDAC epithelial architecture that drives PDAC progression and (Aim 2) determine the functional consequences of PDAC epithelial architecture on PDAC progression. With the completion of this aims, we expect: (Aim 1) to identify ion and water channels that are important for lumen structure as well as PDAC progression, revealing potential novel targets for therapeutic intervention, and (Aim 2) to uncover YAP’s role in PDAC progression and guide the development of YAP- targeted therapies.

Hepatotoxicity of Legacy and Replacement PFAS: Role of BRUCE-Mitochondrial Interactions

Epidemiological studies have shown a strong association between exposure to PFAS (Per- and Poly- fluoroalkyl Substances) and liver toxicity. Particularly, legacy C8-PFAS members, PFOS (perfluorooctane sulfonate) and PFOA (perfluorooctanoic acid), are highly toxic, with PFOS estimated to be approximately 10 times more toxic than PFOA in ecotoxicity models. Consequently, PFAS replacements such as GenX and PFBS are marketed as safe alternatives, although growing evidence indicates that these substitutes also exhibit toxic effects. Lab animal model studies have shown hepatotoxic effects of both legacy and replacement PFAS members, characterized by Metabolic dysfunction-associated steatotic liver disease (MASLD) and its severe form Metabolic dysfunction- associated steatohepatitis (MASH), the two chronic liver diseases affecting an estimated 80-100 million Americans. The broader objective of this project is to understand the underlying mechanisms of PFAS hepatotoxicity in MASLD/MASH. In this context, our initial studies have shown that PFAS exposure of mice downregulates hepatic BRUCE, an autophagy inhibitor, resulting in development of MASLD in WT, and more severe MASLD and even progression to MASH in BRUCE liver-knockdown (BKO) mice. Using primary hepatocytes, we found PFAS-induced BRUCE reduction compromised mitochondrial (mt) functions (respiration, fatty acid oxidation/FAO, and ATP production) and suppressed mitophagy in WT and more so in BKO mice. Pharmacological restoration of mt function in mice prevented PFAS-induced MASLD/MASH. Guided by these compelling preliminary data and scientific premise, we hypothesize that PFAS degradation of BRUCE in hepatocytes induces excessive autophagy (resulting in cytotoxicity) and inhibits mitophagy (resulting in accumulation of damaged mitochondria), leading to release of mtDAMPs to activate inflammation/ fibrosis, thereby facilitating progression from MASLD to MASH. We will test this by three specific aims. Aim 1 (ex vivo) is to determine the human-relevant PFAS doses that modulate BRUCE levels for homeostatic vs cytotoxic autophagy and how BRUCE in turn regulates autophagy. Aim 2 (ex vivo) will investigate BRUCE-driven mitophagy pathway specific to PFAS exposure at human-relevant doses. Aim 3 (ex vivo and in vivo) will involve ex vivo simulation experiments to characterize the role of PFAS-induced, BRUCE-dependent hepatocyte- released mt DAMPs in activation of immune and fibrogenic cells using co-culture assays. Next, we will perform in vivo intervention to validate the role of PFAS-damaged mitochondria in driving MASH progression in mouse models. Furthermore, human relevance of the delineated mechanisms will be ascertained and validated using iPSC-derived human liver organoid system. Impact: This project will advance our understanding of autophagy/mitophagy-centric mechanisms with therapeutic potential in the context of PFAS-induced liver disease MASLD/MASH.

Airway Epithelial Defense Mechanisms in Combating STAT3-Deficiency-Related Lung Infections

Airway Epithelial Defense Mechanisms in Combating STAT3-Deficiency-Related Lung Infections Signal transducer and activator of transcription 3 (STAT3) regulates the expression of genes essential for various cellular processes, including survival, proliferation, differentiation, self-renewal, angiogenesis, and immune response. Abnormal and persistent STAT3 activation is detected in diverse human cancers, driving multiple pro- oncogenic functions. Multiple antitumor drug development targets the inhibition of STAT3 to treat various types of cancer. Unfortunately, downregulated STAT3 significantly increases host susceptibility to recurrent infections, especially pneumonia. Additionally, individuals with genetic polymorphisms associated with lower STAT3 expression are more susceptible to severe tuberculosis. Furthermore, patients with autosomal dominant hyper- IgE syndrome (AD-HIES), also known as Job Syndrome, which is caused by de novo STAT3 mutations and substantially decreased STAT3 expression, have a significantly increased susceptibility to bacterial and fungal infections, with high mortality rates and a shortened life span often associated with Pseudomonas aeruginosa infections. Gram-negative bacteria, particularly P. aeruginosa, are opportunistic pathogens that frequently cause hospital-acquired infections. The problems are worsened by the emerging P. aeruginosa with multidrug resistance (MDR), especially in patients with repeated antibiotic treatments, such as Job Syndrome sufferers. Notably, airway epithelial cell-derived proteins play a significant role in the antimicrobial milieu, promoting effective host defense against invading pathogens. One of the most critical STAT3-regulated antimicrobial molecules is bactericidal permeability-increasing protein fold A1 (BPIFA1, also known as SPLUNC1), a multifunctional innate immunity molecule and indispensable host defense protein that is abundantly secreted in the lungs. This application aims to elucidate how STAT3 deficiency impairs host epithelial defense against microbial infections and whether BPIFA1-mediated innate immune responses can sufficiently restore effective antimicrobial protection to prevent pneumonia. The long-term objective is to advance our understanding of the respiratory innate immune response, particularly in relation to epithelial cell-specific antimicrobial defense. We characterized BPIFA1 as an airway lining fluid protein secreted apically in the airway lumen and in primary human airway epithelial cultures. In this study, we hypothesize that mucosal BPIFA1 is an essential antimicrobial protein that plays a critical role in host defense against microbial infections in STAT3-deficiency- associated pneumonia. Our proposed studies will assess innate immunity mechanisms regulating the antimicrobial activity of the airway epithelium in STAT3 deficiency-associated lung infections. By focusing on the crucial epithelial-derived protein product, BPIFA1, our study will provide an alternative treatment for respiratory infections by augmenting native host defense mechanisms in high-risk individuals, including AD-HIES, cancer, and immunocompromised patients.

Multiplex single-cell chemical genomics to identify small molecule modulators of tumor cell-intrinsic immunogenicity in glioblastoma

PROJECT SUMMARY/ABSTRACT Glioblastoma multiforme is the most common and aggressive primary brain cancer. Despite a multimodal treatment regimen of surgical resection, chemotherapy, radiotherapy, and tumor-treating fields, most patients succumb to the disease within two years of diagnosis. Cancer immunotherapy strategies have emerged as a powerful tool for treating aggressive solid tumors such as melanoma and non-small cell lung cancer. However, current strategies have led to low response rates in glioblastoma, resulting from its low immunogenicity. The proposed research program aims to identify small molecules capable of increasing the immunogenicity of glioblastoma cells, focusing on altering gene expression programs associated with recognition by the immune system and the ability of cytotoxic immune cells to target glioblastoma for destruction. We will use highly multiplex chemical transcriptomic profiling to determine the molecular consequence of exposing glioblastoma neurosphere models to 3,792 small molecules, targeting the majority of cellular activities and clinically relevant drug targets as well as a collection of previously identified immunomodulators. We will then determine how each exposure alters the expression of gene programs associated with tumor cell immunogenicity and response to therapy, including the expression of genes associated with the recognition by the immune system and those associated with immune checkpoints, as well as programs more broadly correlated with resistance to anti-cancer therapies. Chemical hits that meet specific criteria will be subjected to a medicinal chemistry review to further classify compounds by their suitability for treating malignancies in the brain. We will then screen chemical hits to determine their ability to modulate immune-mediated tumor cell killing using tumor- immune cell co-culture. Lastly, we will leverage gene editing and flow cytometry to validate hits based on on- target molecular effects and further refine the mechanism of action by inspecting the ability of drugs to modulate immunogenic programs at the protein level. Our chemical genomics screens aim to provide crucial information regarding the link between pathway activity and immunomodulation in GBM, a critical step to guide future efforts in GBM immunotherapy. More broadly, our study will establish single-cell chemical genomics as a scalable platform for phenotype-based screening for preclinical prioritization of chemical modulators of complex transcriptional phenotypes and provide a framework for hit prioritization, establishment of pipeline robustness and hit validation in the context of single- cell chemical genomics screens.

Host-pathogen-microbiome interactions in Mycoplasma genitalium pathology and treatment: experiments in a 3D organotypic cervical epithelium model to strengthen clinical guidelines

ABSTRACT Mycoplasma genitalium (MG) is an emerging sexually transmitted pathogen whose clinical outcomes in women are poorly understood. Unlike other bacterial sexually transmitted infections (STI), the CDC does not recommend MG screening for asymptomatic women because it is unclear how often asymptomatic MG leads to adverse reproductive outcomes like cervicitis, which can lead to further adverse outcomes, including pelvic inflammatory disease, infertility, and ectopic pregnancy. Epidemiologic data on MG and cervicitis are mixed, and mechanistic data primarily come from models that did not faithfully recapitulate in vivo cervical microphysiological conditions. Key elements they lacked are cervical mucus, which mediates host-pathogen interactions, and the cervicovaginal microbiota. The microbiota appears to contribute to MG outcomes, and our preliminary epidemiologic data indicate that MG and bacterial vaginosis (BV) may synergize to promote cervicitis. MG care is further complicated by its ongoing rise in antibiotic resistance. Resistance-guided therapy and novel antibiotics improve treatment outcomes, but these are not available in the US. Recent clinical and in vitro data indicate that metronidazole and tinidazole, two antibiotics that are available in the US and used to treat BV, may hold promise for improving MG treatment outcomes. The overall objective of this R21 is to generate robust experimental data to clarify MG pathology, evaluate potential therapies, and inform more thorough and actionable clinical recommendations. We developed an innovative in vitro 3D organotypic model of the cervical epithelium that is ideally suited for investigating MG pathology, host-MG-microbiota interactions, and potential therapies. The model uses primary human cervical cells and better recapitulates cervical epithelial structure and physiology (including cervical mucus production) than prior 2D models. It also allows for simultaneous STI infection and co- culture of live cervicovaginal microbiota. Using the 3D organotypic cervical epithelium model, we will determine if MG causes microbiota-dependent cervical epithelial damage, a hallmark of cervicitis (Aim 1), and we will test if metronidazole and tinidazole arrest MG infection (Aim 2). In both Aims, we will interrogate the potential mediating role of the microbiota by inoculating models with live representative cervicovaginal microbiota, and we will assess host-MG-microbiota interactions via transcriptomics. We hypothesize that a polymicrobial BV-like microbiota will exacerbate MG-induced cervical epithelial damage, and removal of a polymicrobial BV microbiota will partially mediate metronidazole’s and tinidazole’s anti-MG activity. The proposed Aims have high translational potential and will provide crucial pre-clinical evidence to inform more thorough and actionable MG testing and treatment guidelines and improve reproductive health outcomes. This R21 will generate some of the first experimental data on MG-host and MG-microbiota interactions, which we will use to support an R01 to validate these interactions during in vivo MG infection and identify novel therapeutic targets for MG.

Multi-modal Micro Electrode Fluidic Array (MEFA) Shells for Brain Organoids

Abstract Brain organoids (BOs) derived from human stem cells bridge the gap between monolayer cell culture studies and animal models, which have well-documented limitations. Monolayer cell culture models fail to accurately replicate the 3D interconnectivity in the brain; animal models, while helpful, are limited due to interspecies differences, with most research focusing on rather phenotypical rather than mechanistic aspects. Concurrent with the advancement of BO models is the urgent need to develop 3D micro instrumentation supporting these organoids to investigate brain development and disease in their accurate physiological environment. Conventional microelectrode arrays (MEAs) used for neuronal cell culture studies are planar, which limits recording access to a small fraction of cells on the bottom side of the organoid. Also, conventional microfluidics is inherently planar, and while recent advances in 3D MEAs and 3D microfluidics have enabled electrical and chemical interrogation in 3D, combining both features with tunability and precision to allow independent and simultaneous control is challenging. Recently, we reported new 3D micro instrumentation in the form of 3D shell MEAs and demonstrated its applicability for electrical recording from BOs. They feature lithographically patterned and chip-integrated electrodes and self-folding polymer shells that can be triggered to wrap around BOs to measure electrical activity from the entire organoid surface. The 3D MEA shell system is modeled on and resembles a miniaturized electroencephalography (EEG) cap; the process used to make them is size-scalable, chip-integrated, and mass- producible. In the research, we aim to develop and validate 3D Micro Electrode Fluidic Array (MEFA) shells with multi-modal electrical recording and biochemical control capabilities, offering high spatiotemporal resolution, tunability, and scalability. Since 3D spatiotemporal patterns of neurochemicals play a critical role in molecular and cellular events of neural development and disease, we propose to apply and validate the MEFA shells in two studies that mimic neurodevelopment and monitor the spatiotemporal effects in neurological disorders and their treatments in vitro. We anticipate that the proposed 3D MEFAs would revolutionize brain sciences by permitting real-time, in-situ studies of electrical and chemical stimulation and interrogation of BOs in a high- throughput manner. The proposed 3D scalable, reproducible, and tunable 3D micro instrumentation for BOs has broad relevance to understanding brain development in utero and the development of anatomically accurate drug and toxicity screening platforms for brain sciences and neurological disorders.

Targeting the fibrogenic ECM as an alternative approach to treating IPF

Project Abstract Idiopathic pulmonary fibrosis and, more broadly, progressive pulmonary fibrosis are wound healing disorders whose hallmark is unorganized and unchecked extracellular matrix (ECM) deposition leading to scarring/stiffening of the lung interstitium. A highly complex, multicellular process, the generation of scar itself is primarily a function of activated fibroblasts with contributions from multiple subpopulations and non-fibroblastic cells. Myofibroblasts, the contractile cohort of activated fibroblasts, physically perturb (i.e. stretch) the local ECM microenvironment, which we have recently shown triggers site-specific, stretch-dependent conformational changes within the ECM protein fibronectin. We have previously demonstrated that a specific stretch-induced conformational change in the critical receptor binding domain of fibronectin triggers a cellular “integrin switch”, a stark change in the ECM receptors used by cells to engage fibronectin. This integrin switch is sufficient to drive activation of naïve lung fibroblasts, acquisition of mesenchymal characteristics in alveolar epithelial cells, and pathogenic remodeling of vascular structures. In this proposal we hypothesize that fibronectin displays a stretch- dependent conformational change specifically in regions of active lung fibrogenesis and that this conformational change disrupts homeostatic integrin binding dynamics in fibroblasts, leading to their acquisition of a pro-fibrogenic phenotype and transcriptional program. We address this hypothesis in a systematic way through three proposed aims. The first aim focuses on quantifying the presence and spatial localization of the stretch-induced conformational change within a cohort of lung fibrosis patient tissue samples, determining if it represents a consistent marker of active fibrogenic regions and elucidation of critical microenvironmental signatures that further expand our understanding of the impact of fibronectin's integrin switch in driving disease. In the second aim we will begin to unravel the molecular mechanism explaining how the integrin switch that emerges because of the stretch-induced conformational change drives fibroblast activation and fibrogenic gene programs using both idealized in vitro culture systems as well as ex vivo human disease tissue models. Finally, in the third aim we will explore the therapeutic potential of binding and blocking this specific stretch-induced conformation of fibronectin using a promising new and potential antibody drug in both in vivo and ex vivo models of disease.

Pharmacological exploitation of neurotrophins and their receptors to develop novel therapeutic approaches against neurodegenerative diseases and brain trauma

Neurotrophins (NGF, BDNF, NT-3) are endogenous growth factors that exert neuroprotective effects by preventing neuronal death and promoting neurogenesis. They act by binding to their respective high-affinity, pro-survival receptors TrkA, TrkB or TrkC, as well as to p75NTR death receptor. While these molecules have been shown to significantly slow or prevent neurodegeneration, their reduced bioavailability and inability to penetrate the blood-brain-barrier limit their use as potential therapeutics. To bypass these limitations, our research team has developed and patented small-sized, lipophilic compounds which selectively resemble neurotrophins’ effects, presenting preferable pharmacological properties and promoting neuroprotection and repair against neurodegeneration. In addition, the combination of these molecules with 3D cultured human neuronal cells, and their targeted delivery in the brain ventricles through soft robotic systems, could offer novel therapeutic approaches against neurodegenerative diseases and brain trauma.

Rett syndrome, MECP2 and therapeutic strategies

The development of the iPS cell technology has revolutionized our ability to study development and diseases in defined in vitro cell culture systems. The talk will focus on Rett Syndrome and discuss two topics: (i) the use of gene editing as an approach to therapy and (ii) the role of MECP2 in gene expression (i) The mutation of the X-linked MECP2 gene is causative for the disease. In a female patient, every cell has a wt copy that is, however, in 50% of the cells located on the inactive X chromosome. We have used epigenetic gene editing tools to activate the wt MECP2 allele on the inactive X chromosome. (ii) MECP2 is thought to act as repressor of gene expression. I will present data which show that MECP2 binds to Pol II and acts as an activator for thousands of genes. The target genes are significantly enriched for Autism related genes. Our data challenge the established model of MECP2’s role in gene expression and suggest novel therapeutic approaches.

NOTE: DUE TO A CYBER ATTACK OUR UNIVERSITY WEB SYSTEM IS SHUT DOWN - TALK WILL BE RESCHEDULED

The size and structure of the dendritic arbor play important roles in determining how synaptic inputs of neurons are converted to action potential output and how neurons are integrated in the surrounding neuronal network. Accordingly, neurons with aberrant morphology have been associated with neurological disorders. Dysmorphic, enlarged neurons are, for example, a hallmark of focal epileptogenic lesions like focal cortical dysplasia (FCDIIb) and gangliogliomas (GG). However, the regulatory mechanisms governing the development of dendrites are insufficiently understood. The evolutionary conserved Ste20/Hippo kinase pathway has been proposed to play an important role in regulating the formation and maintenance of dendritic architecture. A key element of this pathway, Ste20-like kinase (SLK), regulates cytoskeletal dynamics in non-neuronal cells and is strongly expressed throughout neuronal development. Nevertheless, its function in neurons is unknown. We found that during development of mouse cortical neurons, SLK has a surprisingly specific role for proper elaboration of higher, ≥ 3rd, order dendrites both in cultured neurons and living mice. Moreover, SLK is required to maintain excitation-inhibition balance. Specifically, SLK knockdown causes a selective loss of inhibitory synapses and functional inhibition after postnatal day 15, while excitatory neurotransmission is unaffected. This mechanism may be relevant for human disease, as dysmorphic neurons within human cortical malformations exhibit significant loss of SLK expression. To uncover the signaling cascades underlying the action of SLK, we combined phosphoproteomics, protein interaction screens and single cell RNA seq. Overall, our data identifies SLK as a key regulator of both dendritic complexity during development and of inhibitory synapse maintenance.

Internal representation of musical rhythm: transformation from sound to periodic beat

When listening to music, humans readily perceive and move along with a periodic beat. Critically, perception of a periodic beat is commonly elicited by rhythmic stimuli with physical features arranged in a way that is not strictly periodic. Hence, beat perception must capitalize on mechanisms that transform stimulus features into a temporally recurrent format with emphasized beat periodicity. Here, I will present a line of work that aims to clarify the nature and neural basis of this transformation. In these studies, electrophysiological activity was recorded as participants listened to rhythms known to induce perception of a consistent beat across healthy Western adults. The results show that the human brain selectively emphasizes beat representation when it is not acoustically prominent in the stimulus, and this transformation (i) can be captured non-invasively using surface EEG in adult participants, (ii) is already in place in 5- to 6-month-old infants, and (iii) cannot be fully explained by subcortical auditory nonlinearities. Moreover, as revealed by human intracerebral recordings, a prominent beat representation emerges already in the primary auditory cortex. Finally, electrophysiological recordings from the auditory cortex of a rhesus monkey show a significant enhancement of beat periodicities in this area, similar to humans. Taken together, these findings indicate an early, general auditory cortical stage of processing by which rhythmic inputs are rendered more temporally recurrent than they are in reality. Already present in non-human primates and human infants, this "periodized" default format could then be shaped by higher-level associative sensory-motor areas and guide movement in individuals with strongly coupled auditory and motor systems. Together, this highlights the multiplicity of neural processes supporting coordinated musical behaviors widely observed across human cultures.The experiments herein include: a motor timing task comparing the effects of movement vs non-movement with and without feedback (Exp. 1A & 1B), a transcranial magnetic stimulation (TMS) study on the role of the supplementary motor area (SMA) in transforming temporal information (Exp. 2), and a perceptual timing task investigating the effect of noisy movement on time perception with both visual and auditory modalities (Exp. 3A & 3B). Together, the results of these studies support the Bayesian cue combination framework, in that: movement improves the precision of time perception not only in perceptual timing tasks but also motor timing tasks (Exp. 1A & 1B), stimulating the SMA appears to disrupt the transformation of temporal information (Exp. 2), and when movement becomes unreliable or noisy there is no longer an improvement in precision of time perception (Exp. 3A & 3B). Although there is support for the proposed framework, more studies (i.e., fMRI, TMS, EEG, etc.) need to be conducted in order to better understand where and how this may be instantiated in the brain; however, this work provides a starting point to better understanding the intrinsic connection between time and movement

Epigenetic rewiring in Schinzel-Giedion syndrome

During life, a variety of specialized cells arise to grant the right and timely corrected functions of tissues and organs. Regulation of chromatin in defining specialized genomic regions (e.g. enhancers) plays a key role in developmental transitions from progenitors into cell lineages. These enhancers, properly topologically positioned in 3D space, ultimately guide the transcriptional programs. It is becoming clear that several pathologies converge in differential enhancer usage with respect to physiological situations. However, why some regulatory regions are physiologically preferred, while some others can emerge in certain conditions, including other fate decisions or diseases, remains obscure. Schinzel-Giedion syndrome (SGS) is a rare disease with symptoms such as severe developmental delay, congenital malformations, progressive brain atrophy, intractable seizures, and infantile death. SGS is caused by mutations in the SETBP1 gene that results in its accumulation further leading to the downstream accumulation of SET. The oncoprotein SET has been found as part of the histone chaperone complex INHAT that blocks the activity of histone acetyltransferases suggesting that SGS may (i) represent a natural model of alternative chromatin regulation and (ii) offer chances to study downstream (mal)adaptive mechanisms. I will present our work on the characterization of SGS in appropriate experimental models including iPSC-derived cultures and mouse.

Cholesterol and matrisome pathways dysregulated in Alzheimer’s disease brain astrocytes and microglia

The impact of apolipoprotein E ε4 (APOE4), the strongest genetic risk factor for Alzheimer’s disease (AD), on human brain cellular function remains unclear. Here, we investigated the effects of APOE4 on brain cell types derived from population and isogenic human induced pluripotent stem cells, post-mortem brain, and APOE targeted replacement mice. Population and isogenic models demonstrate that APOE4 local haplotype, rather than a single risk allele, contributes to risk. Global transcriptomic analyses reveal human-specific, APOE4-driven lipid metabolic dysregulation in astrocytes and microglia. APOE4 enhances de novo cholesterol synthesis despite elevated intracellular cholesterol due to lysosomal cholesterol sequestration in astrocytes. Further, matrisome dysregulation is associated with upregulated chemotaxis, glial activation, and lipid biosynthesis in astrocytes co-cultured with neurons, which recapitulates altered astrocyte matrisome signaling in human brain. Thus, APOE4 initiates glia-specific cell and non-cell autonomous dysregulation that may contribute to increased AD risk." https://doi.org/10.1016/j.cell.2022.05.017

How can we shift research culture to drive Credibility in Neuroscience?

This webinar will demonstrate changes that are already happening at individual, institutional and funder level to shift research culture toward supporting credible research, and will allow attendees working in neuroscience to ask further questions to our speakers. Our panel of speakers, chaired by Ana Dorrego-Rivas: Emily Farran, Professor in Developmental Psychology and Academic Lead Research Culture and Integrity at the University of Surrey Rosa Sancho, Head of Research at Alzheimer's Research UK Sepideh Keshavarzi, Senior Research Fellow at the Sainsbury Wellcome Centre

Bridging the gap between artificial models and cortical circuits

Artificial neural networks simplify complex biological circuits into tractable models for computational exploration and experimentation. However, the simplification of artificial models also undermines their applicability to real brain dynamics. Typical efforts to address this mismatch add complexity to increasingly unwieldy models. Here, we take a different approach; by reducing the complexity of a biological cortical culture, we aim to distil the essential factors of neuronal dynamics and plasticity. We leverage recent advances in growing neurons from human induced pluripotent stem cells (hiPSCs) to analyse ex vivo cortical cultures with only two distinct excitatory and inhibitory neuron populations. Over 6 weeks of development, we record from thousands of neurons using high-density microelectrode arrays (HD-MEAs) that allow access to individual neurons and the broader population dynamics. We compare these dynamics to two-population artificial networks of single-compartment neurons with random sparse connections and show that they produce similar dynamics. Specifically, our model captures the firing and bursting statistics of the cultures. Moreover, tightly integrating models and cultures allows us to evaluate the impact of changing architectures over weeks of development, with and without external stimuli. Broadly, the use of simplified cortical cultures enables us to use the repertoire of theoretical neuroscience techniques established over the past decades on artificial network models. Our approach of deriving neural networks from human cells also allows us, for the first time, to directly compare neural dynamics of disease and control. We found that cultures e.g. from epilepsy patients tended to have increasingly more avalanches of synchronous activity over weeks of development, in contrast to the control cultures. Next, we will test possible interventions, in silico and in vitro, in a drive for personalised approaches to medical care. This work starts bridging an important theoretical-experimental neuroscience gap for advancing our understanding of mammalian neuron dynamics.

Root causes and possible solutions to academic bullying in higher education

Academic bullying is a serious issue that affects all disciplines and people of all levels of experience. To create a truly safe, productive, and vibrant environment in academia requires coordinated and collaborative input as well as the action of a variety of stakeholders, including scholarly communities, funding agencies, and institutions. This talk will focus on a framework of integrated responding, in which stakeholders as responsible and response-able parties could proactively collaborate and coordinate to reduce the incidence and consequences of academic bullying while at the same time building constructive academic cultures. The outcome of such a framework would be to create novel entities and actions that accelerate successful responses to academic bullying.

Cell-type specific genomics and transcriptomics of HIV in the brain

Exploration of genome organization and function in the HIV infected brain is critical to aid in the understanding and development of treatments for HIV-associated neurocognitive disorder (HAND). Here, we applied a multiomic approach, including single nuclei transcriptomics, cell-type specific Hi-C 3D genome mapping, and viral integration site sequencing (IS-seq) to frontal lobe tissue from HIV-infected individuals with encephalitis (HIVE) and without encephalitis (HIV+). We observed reorganization of open/repressive (A/B) compartment structures in HIVE microglia encompassing 6.4% of the genome with enrichment for regions containing interferon (IFN) pathway genes. 3D genome remodeling was associated with transcriptomic reprogramming, including down-regulation of cell adhesion and synapse-related functions and robust activation of IFN signaling and cell migratory pathways, and was recapitulated by IFN-g stimulation of cultured microglial cells. Microglia from HIV+ brains showed, to a lesser extent, similar transcriptional alterations. IS-seq recovered 1,221 integration sites in the brain that were enriched for chromosomal domains newly mobilized into a permissive chromatin environment in HIVE microglia. Viral transcription, which was detected in 0.003% of all nuclei in HIVE brain, occurred in a subset of highly activated microglia that drove differential expression in HIVE. Thus, we observed a dynamic interrelationship of interferon-associated 3D genome and transcriptome remodeling with HIV integration and transcription in the brain.

How communication networks promote cross-cultural similarities: The case of category formation

Individuals vary widely in how they categorize novel phenomena. This individual variation has led canonical theories in cognitive and social science to suggest that communication in large social networks leads populations to construct divergent category systems. Yet, anthropological data indicates that large, independent societies consistently arrive at similar categories across a range of topics. How is it possible for diverse populations, consisting of individuals with significant variation in how they view the world, to independently construct similar categories? Through a series of online experiments, I show how large communication networks within cultures can promote the formation of similar categories across cultures. For this investigation, I designed an online “Grouping Game” to observe how people construct categories in both small and large populations when tasked with grouping together the same novel and ambiguous images. I replicated this design for English-speaking subjects in the U.S. and Mandarin-speaking subjects in China. In both cultures, solitary individuals and small social groups produced highly divergent category systems. Yet, large social groups separately and consistently arrived at highly similar categories both within and across cultures. These findings are accurately predicted by a simple mathematical model of critical mass dynamics. Altogether, I show how large communication networks can filter lexical diversity among individuals to produce replicable society-level patterns, yielding unexpected implications for cultural evolution. In particular, I discuss how participants in both cultures readily harnessed analogies when categorizing novel stimuli, and I examine the role of communication networks in promoting cross-cultural similarities in analogy-making as the key engine of category formation.

Malignant synaptic plasticity in pediatric high-grade gliomas

Pediatric high-grade gliomas (pHGG) are a devastating group of diseases that urgently require novel therapeutic options. We have previously demonstrated that pHGGs directly synapse onto neurons and the subsequent tumor cell depolarization, mediated by calcium-permeable AMPA channels, promotes their proliferation. The regulatory mechanisms governing these postsynaptic connections are unknown. Here, we investigated the role of BDNF-TrkB signaling in modulating the plasticity of the malignant synapse. BDNF ligand activation of its canonical receptor, TrkB (which is encoded for by the gene NTRK2), has been shown to be one important modulator of synaptic regulation in the normal setting. Electrophysiological recordings of glioma cell membrane properties, in response to acute neurotransmitter stimulation, demonstrate in an inward current resembling AMPA receptor (AMPAR) mediated excitatory neurotransmission. Extracellular BDNF increases the amplitude of this glutamate-induced tumor cell depolarization and this effect is abrogated in NTRK2 knockout glioma cells. Upon examining tumor cell excitability using in situ calcium imaging, we found that BDNF increases the intensity of glutamate-evoked calcium transients in GCaMP6s expressing glioma cells. Western blot analysis indicates the tumors AMPAR properties are altered downstream of BDNF induced TrkB activation in glioma. Cell membrane protein capture (via biotinylation) and live imaging of pH sensitive GFP-tagged AMPAR subunits demonstrate an increase of calcium permeable channels at the tumors postsynaptic membrane in response to BDNF. We find that BDNF-TrkB signaling promotes neuron-to-glioma synaptogenesis as measured by high-resolution confocal and electron microscopy in culture and tumor xenografts. Our analysis of published pHGG transcriptomic datasets, together with brain slice conditioned medium experiments in culture, indicates the tumor microenvironment as the chief source of BDNF ligand. Disruption of the BDNF-TrkB pathway in patient-derived orthotopic glioma xenograft models, both genetically and pharmacologically, results in an increased overall survival and reduced tumor proliferation rate. These findings suggest that gliomas leverage normal mechanisms of plasticity to modulate the excitatory channels involved in synaptic neurotransmission and they reveal the potential to target the regulatory components of glioma circuit dynamics as a therapeutic strategy for these lethal cancers.

Why is the suprachiasmatic nucleus such a brilliant circadian time-keeper?

Circadian clocks dominate our lives. By creating and distributing an internal representation of 24-hour solar time, they prepare us, and thereby adapt us, to the daily and seasonal world. Jet-lag is an obvious indicator of what can go wrong when such adaptation is disrupted acutely. More seriously, the growing prevalence of rotational shift-work which runs counter to our circadian life, is a significant chronic challenge to health, presenting as increased incidence of systemic conditions such as metabolic and cardiovascular disease. Added to this, circadian and sleep disturbances are a recognised feature of various neurological and psychiatric conditions, and in some cases may contribute to disease progression. The “head ganglion” of the circadian system is the suprachiasmatic nucleus (SCN) of the hypothalamus. It synchronises the, literally, innumerable cellular clocks across the body, to each other and to solar time. Isolated in organotypic slice culture, it can maintain precise, high-amplitude circadian cycles of neural activity, effectively, indefinitely, just as it does in vivo. How is this achieved: how does this clock in a dish work? This presentation will consider SCN time-keeping at the level of molecular feedback loops, neuropeptidergic networks and neuron-astrocyte interactions.

Using Human Stem Cells to Uncover Genetic Epilepsy Mechanisms

Reprogramming somatic cells to a pluripotent state via the induced pluripotent stem cell (iPSC) method offers an increasingly utilized approach for neurological disease modeling with patient-derived cells. Several groups, including ours, have applied the iPSC approach to model severe genetic developmental and epileptic encephalopathies (DEEs) with patient-derived cells. Although most studies to date involve 2-D cultures of patient-derived neurons, brain organoids are increasingly being employed to explore genetic DEE mechanisms. We are applying this approach to understand PMSE (Polyhydramnios, Megalencephaly and Symptomatic Epilepsy) syndrome, Rett Syndrome (in collaboration with Ben Novitch at UCLA) and Protocadherin-19 Clustering Epilepsy (PCE). I will describe our findings of robust structural phenotypes in PMSE and PCE patient-derived brain organoid models, as well as functional abnormalities identified in fusion organoid models of Rett syndrome. In addition to showing epilepsy-relevant phenotypes, both 2D and brain organoid cultures offer platforms to identify novel therapies. We will also discuss challenges and recent advances in the brain organoid field, including a new single rosette brain organoid model that we have developed. The field is advancing rapidly and our findings suggest that brain organoid approaches offers great promise for modeling genetic neurodevelopmental epilepsies and identifying precision therapies.

Understanding Perceptual Priors with Massive Online Experiments

One of the most important questions in psychology and neuroscience is understanding how the outside world maps to internal representations. Classical psychophysics approaches to this problem have a number of limitations: they mostly study low dimensional perpetual spaces, and are constrained in the number and diversity of participants and experiments. As ecologically valid perception is rich, high dimensional, contextual, and culturally dependent, these impediments severely bias our understanding of perceptual representations. Recent technological advances—the emergence of so-called “Virtual Labs”— can significantly contribute toward overcoming these barriers. Here I present a number of specific strategies that my group has developed in order to probe representations across a number of dimensions. 1) Massive online experiments can increase significantly the amount of participants and experiments that can be carried out in a single study, while also significantly diversifying the participant pool. We have developed a platform, PsyNet, that enables “experiments as code,” whereby the orchestration of computer servers, recruiting, compensation of participants, and data management is fully automated and every experiment can be fully replicated with one command line. I will demonstrate how PsyNet allows us to recruit thousands of participants for each study with a large number of control experimental conditions, significantly increasing our understanding of auditory perception. 2) Virtual lab methods also enable us to run experiments that are nearly impossible in a traditional lab setting. I will demonstrate our development of adaptive sampling, a set of behavioural methods that combine machine learning sampling techniques (Monte Carlo Markov Chains) with human interactions and allow us to create high-dimensional maps of perceptual representations with unprecedented resolution. 3) Finally, I will demonstrate how the aforementioned methods can be applied to the study of perceptual priors in both audition and vision, with a focus on our work in cross-cultural research, which studies how perceptual priors are influenced by experience and culture in diverse samples of participants from around the world.

Capacitance clamp - artificial capacitance in biological neurons via dynamic clamp

A basic time scale in neural dynamics from single cells to the network level is the membrane time constant - set by a neuron’s input resistance and its capacitance. Interestingly, the membrane capacitance appears to be more dynamic than previously assumed with implications for neural function and pathology. Indeed, altered membrane capacitance has been observed in reaction to physiological changes like neural swelling, but also in ageing and Alzheimer's disease. Importantly, according to theory, even small changes of the capacitance can affect neuronal signal processing, e.g. increase network synchronization or facilitate transmission of high frequencies. In experiment, robust methods to modify the capacitance of a neuron have been missing. Here, we present the capacitance clamp - an electrophysiological method for capacitance control based on an unconventional application of the dynamic clamp. In its original form, dynamic clamp mimics additional synaptic or ionic conductances by injecting their respective currents. Whereas a conductance directly governs a current, the membrane capacitance determines how fast the voltage responds to a current. Accordingly, capacitance clamp mimics an altered capacitance by injecting a dynamic current that slows down or speeds up the voltage response (Fig 1 A). For the required dynamic current, the experimenter only has to specify the original cell and the desired target capacitance. In particular, capacitance clamp requires no detailed model of present conductances and thus can be applied in every excitable cell. To validate the capacitance clamp, we performed numerical simulations of the protocol and applied it to modify the capacitance of cultured neurons. First, we simulated capacitance clamp in conductance based neuron models and analysed impedance and firing frequency to verify the altered capacitance. Second, in dentate gyrus granule cells from rats, we could reliably control the capacitance in a range of 75 to 200% of the original capacitance and observed pronounced changes in the shape of the action potentials: increasing the capacitance reduced after-hyperpolarization amplitudes and slowed down repolarization. To conclude, we present a novel tool for electrophysiology: the capacitance clamp provides reliable control over the capacitance of a neuron and thereby opens a new way to study the temporal dynamics of excitable cells.

Untitled Seminar

Leah Krubitzer is a Distinguished Professor in the Department of Psychology at the University of California, Davis. Her graduate work focused on the evolution of visual cortex in primates, and she extended her research in Australia to include monotremes and marsupials. She has worked on the brains of over 45 different mammals. Her current research focuses on the impact of early experience and how culture impacts brain development. She also examines the evolution of sensory motor networks involved in manual dexterity, reaching and grasping in mammals. She received a MacArthur award for her work on evolution.

Using human pluripotent stem cells to model obesity in vitro

Obesity and neurodegeneration lead to millions of premature deaths each year and lack broadly effective treatments. Obesity is largely caused by the abnormal function of cell populations in the hypothalamus that regulate appetite. We have developed methods generate human hypothalamic neurons from hPSCs to study how they respond to nutrients and hormones (e.g. leptin) and how disease-associated mutations alter their function. Since human hypothalamic neurons can be produced in large numbers, are functionally responsive, have a human genome that can be readily edited, and are in culture environment that can be readily controlled, there is an unprecedented opportunity to study the genetic and environmental factors underlying obesity. In addition, we are fascinated by the fact that mid-life obesity is a risk factor for dementia later in life, and caloric restriction, exercise, and certain anti-obesity drugs are neuroprotective, suggesting that there are shared mechanisms between obesity and neurodegeneration. Studies of HPSC-derived hypothalamic neurons may help bridge the mechanistic gulf between human genetic data and organismic phenotypes, revealing new therapeutic targets. ​

Analogy as a Catalyst for Cumulative Cultural Evolution

Analogies, broadly defined, map novel concepts onto familiar concepts, making them essential for perception, reasoning, and communication. We argue that analogy-building served a critical role in the evolution of cumulative culture, by allowing humans to learn and transmit complex behavioural sequences that would otherwise be too cognitively demanding or opaque to acquire. The emergence of a protolanguage consisting of simple labels would have provided early humans with the cognitive tools to build explicit analogies and to communicate them to others. This focus on analogy-building can shed new light on the coevolution of cognition and culture, and addresses recent calls for better integration of the field of cultural evolution with cognitive science. This talk will address what cumulative cultural evolution is, how we define analogy-building, how analogy-building applies to cumulative cultural evolution, how analogy-building fits into language evolution, and the implications of analogy-building for causal understanding and cognitive evolution.

The social contract in miniature: Virtual Bargaining and the theory of joint action, meaning and the foundations of culture

How can people coordinate their actions or make joint decisions? One possibility is that each person attempts to predict the actions of the other(s), and best-responds accordingly. But this can lead to bad outcomes, and sometimes even vicious circularity. An alternative view is that each person attempts to work out what the two or more players would agree to do, if they were to bargain explicitly. If the result of such a "virtual" bargain is "obvious," then the players can simply play their respective roles in that bargain. I suggest that virtual bargaining is essential to genuinely social interaction (rather than viewing other people as instruments), and may even be uniquely human. This approach aims to respect methodological individualism, a key principle in many areas of social science, while explaining how human groups can, in a very real sense, be "greater" than the sum of their individual members.

Space for Thinking - Spatial Reference Frames and Abstract Concepts

People from cultures around the world tend to borrow from the domain of space to represent abstract concepts. For example, in the domain on time, we use spatial metaphors (e.g., describing the future as being in front and the past behind), accompany our speech with spatial gestures (e.g., gesturing to the left to refer to a past event), and use external tools that project time onto a spatial reference frame (e.g., calendars). Importantly, these associations are also present in the way we think and reason about time, suggesting that space and time are also linked in the mind. In this talk, I will explore the developmental origins and functional implications of these types of cross-dimensional associations. To start, I will discuss the roles that language and culture play in shaping how children in the US and India represent time. Next, I will use word learning and memory as test cases for exploring why cross-dimensional associations may be cognitively advantageous. Finally, I will talk about future directions and the practical implications for this line of work, with a focus on how encouraging spatial representations of abstract concepts could improve learning outcomes.

Cognition plus longevity equals culture: A new framework for understanding human brain evolution

Narratives of human evolution have focused on cortical expansion and increases in brain size relative to body size, but considered that changes in life history, such as in age at sexual maturity and thus the extent of childhood and maternal dependence, or maximal longevity, are evolved features that appeared as consequences of selection for increased brain size, or increased cognitive abilities that decrease mortality rates, or due to selection for grandmotherly contribution to feeding the young. Here I build on my recent finding that slower life histories universally accompany increased numbers of cortical neurons across warm-blooded species to propose a simpler framework for human evolution: that slower development to sexual maturity and increased post-maturity longevity are features that do not require selection, but rather inevitably and immediately accompany evolutionary increases in numbers of cortical neurons, thus fostering human social interactions and cultural and technological evolution as generational overlap increases.

Exploration of human neural phenotypic diversity through mixed-donor cultures of stem-cell derived NGN2-accelerated progenitors (SNaPs)

Modulation of C. elegans behavior by gut microbes

We are interested in understanding how microbes impact the behavior of host animals. Animal nervous systems likely evolved in environments richly surrounded by microbes, yet the impact of bacteria on nervous system function has been relatively under-studied. A challenge has been to identify systems in which both host and microbe are amenable to genetic manipulation, and which enable high-throughput behavioral screening in response to defined and naturalistic conditions. To accomplish these goals, we use an animal host — the roundworm C. elegans, which feeds on bacteria — in combination with its natural gut microbiome to identify inter-organismal signals driving host-microbe interactions and decision-making. C. elegans has some of the most extensive molecular, neurobiological and genetic tools of any multicellular eukaryote, and, coupled with the ease of gnotobiotic culture in these worms, represents a highly attractive system in which to study microbial influence on host behavior. Using this system, we discovered that commensal bacterial metabolites directly modulate nervous system function of their host. Beneficial gut microbes of the genus Providencia produce the neuromodulator tyramine in the C. elegans intestine. Using a combination of behavioral analysis, neurogenetics, metabolomics and bacterial genetics we established that bacterially produced tyramine is converted to octopamine in C. elegans, which acts directly in sensory neurons to reduce odor aversion and increase sensory preference for Providencia. We think that this type of sensory modulation may increase association of C. elegans with these microbes, increasing availability of this nutrient-rich food source for the worm and its progeny, while facilitating dispersal of the bacteria.

Carnosine negatively modulates pro-oxidant activities of M1 peripheral macrophages and prevents neuroinflammation induced by amyloid-β in microglial cells

Carnosine is a natural dipeptide widely distributed in mammalian tissues and exists at particularly high concentrations in skeletal and cardiac muscles and brain. A growing body of evidence shows that carnosine is involved in many cellular defense mechanisms against oxidative stress, including inhibition of amyloid-β (Aβ) aggregation, modulation of nitric oxide (NO) metabolism, and scavenging both reactive nitrogen and oxygen species. Different types of cells are involved in the innate immune response, with macrophage cells representing those primarily activated, especially under different diseases characterized by oxidative stress and systemic inflammation such as depression and cardiovascular disorders. Microglia, the tissue-resident macrophages of the brain, are emerging as a central player in regulating key pathways in central nervous system inflammation; with specific regard to Alzheimer’s disease (AD) these cells exert a dual role: on one hand promoting the clearance of Aβ via phagocytosis, on the other hand increasing neuroinflammation through the secretion of inflammatory mediators and free radicals. The activity of carnosine was tested in an in vitro model of macrophage activation (M1) (RAW 264.7 cells stimulated with LPS + IFN-γ) and in a well-validated model of Aβ-induced neuroinflammation (BV-2 microglia treated with Aβ oligomers). An ample set of techniques/assays including MTT assay, trypan blue exclusion test, high performance liquid chromatography, high-throughput real-time PCR, western blot, atomic force microscopy, microchip electrophoresis coupled to laser-induced fluorescence, and ELISA aimed to evaluate the antioxidant and anti-inflammatory activities of carnosine was employed. In our experimental model of macrophage activation (M1), therapeutic concentrations of carnosine exerted the following effects: 1) an increased degradation rate of NO into its non-toxic end-products nitrite and nitrate; 2) the amelioration of the macrophage energy state, by restoring nucleoside triphosphates and counterbalancing the changes in ATP/ADP, NAD+/NADH and NADP+/NADPH ratio obtained by LPS + IFN-γ induction; 3) a reduced expression of pro-oxidant enzymes (NADPH oxidase, Cyclooxygenase-2) and of the lipid peroxidation product malondialdehyde; 4) the rescue of antioxidant enzymes expression (Glutathione peroxidase 1, Superoxide dismutase 2, Catalase); 5) an increased synthesis of transforming growth factor-β1 (TGF-β1) combined with the negative modulation of interleukines 1β and 6 (IL-1β and IL-6), and 6) the induction of nuclear factor erythroid-derived 2-like 2 (Nrf2) and heme oxygenase-1 (HO-1). In our experimental model of Aβ-induced neuroinflammation, carnosine: 1) prevented cell death in BV-2 cells challenged with Aβ oligomers; 2) lowered oxidative stress by decreasing the expression of inducible nitric oxide synthase and NADPH oxidase, and the concentrations of nitric oxide and superoxide anion; 3) decreased the secretion of pro-inflammatory cytokines such as IL-1β simultaneously rescuing IL-10 levels and increasing the expression and the release of TGF-β1; 4) prevented Aβ-induced neurodegeneration in primary mixed neuronal cultures challenged with Aβ oligomers and these neuroprotective effects was completely abolished by SB431542, a selective inhibitor of type-1 TGF-β receptor. Overall, our data suggest a novel multimodal mechanism of action of carnosine underlying its protective effects in macrophages and microglia and the therapeutic potential of this dipeptide in counteracting pro-oxidant and pro-inflammatory phenomena observed in different disorders characterized by elevated levels of oxidative stress and inflammation such as depression, cardiovascular disorders, and Alzheimer’s disease.

The thalamus that speaks to the cortex: spontaneous activity in the developing brain

Our research team runs several related projects studying the cellular and molecular mechanisms involved in the development of axonal connections in the brain. In particular, our aim is to uncover the principles underlying thalamocortical axonal wiring, maintenance and ultimately the rewiring of connections, through an integrated and innovative experimental programme. The development of the thalamocortical wiring requires a precise topographical sorting of its connections. Each thalamic nucleus receives specific sensory information from the environment and projects topographically to its corresponding cortical. A second level of organization is achieved within each area, where thalamocortical connections display an intra-areal topographical organization, allowing the generation of accurate spatial representations within each cortical area. Therefore, the level of organization and specificity of the thalamocortical projections is much more complex than other projection systems in the CNS. The central hypothesis of our laboratory is that thalamocortical input influences and maintains the functional architecture of the sensory cortices. We also believe that rewiring and plasticity events can be triggered by activity-dependent mechanisms in the thalamus. Three major questions are been focused in the laboratory: i) the role of spontaneous patterns of activity in thalamocortical wiring and cortical development, ii) the role of the thalamus and its connectivity in the neuroplastic cortical changes following sensory deprivation, and iii) reprogramming thalamic cells for sensory circuit restoration. Within these projects we are using several experimental programmes, these include: optical imaging, manipulation of gene expression in vivo, cell and molecular biology, biochemistry, cell culture, sensory deprivation paradigms and electrophysiology. The results derived from our investigations will contribute to our understating of how reprogramming of cortical wiring takes place following brain damage and how cortical structure is maintained.

Functional characterization of human iPSC-derived neurons at single-cell resolution

Recent developments in induced pluripotent stem cell (iPSC) technology have enabled easier access to human cells in vitro. With increasing availability of human iPSC-derived neurons, both healthy and disease cell lines, screening compounds for neurodegenerative diseases on human cells can potentially be performed in the earlier stages of drug discovery. To accelerate the functional characterization of iPSC-derived neurons and the effect of compounds, reproducible and relevant results are necessary. In this webinar, the speakers will: Introduce high-resolution functional imaging of human iPSC-derived neurons Showcase how to extract functional features of hundreds of cells in a cell culture sample label-free Discuss electrophysiological parameters for characterizing the differences among several human neuronal cell lines

Chronic optogenetic stimulation has the potential to shape the collective activity of neuronal cell cultures

Bernstein Conference 2024

Analysis of Alzheimer’s disease-related synaptic alterations using microfluidic microglia/neuron co-cultures

Astrocytes regulate drug-induced hyperactivity in neuron-astrocyte co-cultures on microelectrode arrays

Computational tool for comparing development of cellular-scale network activity from microelectrode array (MEA) recordings of 2D neuronal cultures and 3D human cerebral organoids

Cultured brain organoid slices as a model system to study human neurons and glial cells

Cultured mouse dopaminergic neurons as a model system to study alpha-Synuclein aggregation and neurodegeneration in Parkinson’s disease

Development of a mouse 3D-Tri-culture Approach for the Analysis of Neuron-glia Interactions under Physiological and Pathophysiological Conditions

Dose-dependent effects of ketamine on electrophysiological network activity and TrkB-ERK signaling in cortical neuronal culture

The effect of nanostructuration of semi-conductor or polymer materials in neural cell cultures: implications for neural implant design

Empagliflozin effect on the central nervous system: an in vitro study on primary neuronal cell cultures

Endogenous NMDA receptor modulators alter dendritic arbor complexity in cultured cortical neurons

Exploring the Dynamics of Neuronal Excitability by Optogenetics in ex vivo Cortical Cultures

Functional effects of human LGI1 autoantibodies on CA3 pyramidal neurons: a species-specific in vitro study in human hippocampal slice cultures

Generating sleep oscillations using primary and hiPSC-derived thalamo-cortical cultures

Human Brain-Organoids-on-Chip: Advanced microfluidic device for reproducible organoids culture

Impact of Taupathies on the Functional Organization of Neuronal Cultures

Impact of temporal oxygen and glucose deprivation on neonatal astrocytes cultured on the selected biomaterials

Inflammatory exosomes transfer danger signals and induce glial dysfunctional calcium dynamics in naïve spinal cultured explants

Ιnvestigation of ependymal cells in the mouse and human Subependymal Zone: in vivo assessment and in vitro cultures

An all iPSC-derived cortico-striato-nigral minicircuit modelling Parkinson’s Disease revealed electrophysiological changes in medium spiny neurons cocultured with dopaminergic neurons carrying GBA N370S mutation

Modelling monogenic epilepsy in human brain slice cultures

Modulating age-dependent changes of neural mechanical properties affects mechanosignaling and synaptic integrity in neuron-glia cocultures

Multi-Electrode Arrays Reveal Early Network Dysfunction in Primary Hippocampal Neuronal Cultures Derived from the AppNL-G-F Mouse Model of Alzheimer’s Disease

Neuronal uptake evaluation of novel carbon nanoforms encapsulated in polymeric carriers loaded with galantamine on primary neuronal cultures

Neuroprotection of midbrain cultured dopamine neurons by the non-psychoactive phytocannabinoid cannabidiol

Nimodipine reduces LPS-induced microglial activation in primary mixed and isolated microglia cell culture

Revisiting tau involvement in complex neural network remodelling through the analysis of extracellular neuronal activity exhibited by organotypic brain slice co-cultures

Role of BDNF, adenosine A2AR and cannabinoid receptors on postnatal oligodendrogenesis from SVZ-derived neural stem cell cultures

Rostral-to-caudal increase in metabolic activity of cultured ex vivo slices of neonatal rat brain

Transvers-plane-snapshot of signal propagating neuronal pathways reveals relationship between spontaneous and evoked activity in a cultured neuronal circuit

Unravelling the role of the STX1B gene in genetic epilepsy syndromes using an iPSC-derived autaptic culture system

Artifact identification in transfer entropy connectivity inference of neuronal cultures

FENS Forum 2024

Caffeine treatment decreases MAO-B expression, neurite outgrowth, and neurite branching in immature rat primary neuronal cell cultures

FENS Forum 2024

Characterization of a new human co-culture model of endothelial cells, pericytes, and brain organoids in a microfluidic device

FENS Forum 2024

Computation with neuronal cultures: Effects of connectivity modularity on response separation and generalisation in simulations and experiments

FENS Forum 2024

Computer vision and image processing applications on astrocyte-glioma interactions in 3D cell culture

FENS Forum 2024

Deciphering developmental-aging mechanisms in cell culture: Aberrant ADNP cytoplasmic-nuclear crosstalk and NAP (davunetide) protection

FENS Forum 2024

Decoding neuronal identity maintenance and progenitor plasticity in extended brain organoid cultures

FENS Forum 2024

Development of an organ-on-chip platform for the co-culture of mouse organotypic brain slices with endothelial cells

FENS Forum 2024

Dynamic behaviour and functional organization of neuronal cultures grown in substrates with spatial anisotropies

FENS Forum 2024