gene therapy

Gene therapy for hearing loss: where do we go from ear?

Harnessing mRNA metabolism for the development of precision gene therapy

Mutation targeted gene therapy approaches to alter rod degeneration and retain cones

My research uses electrophysiological techniques to evaluate normal retinal function, dysfunction caused by blinding retinal diseases and the restoration of function using a variety of therapeutic strategies. We can use our understanding or normal retinal function and disease-related changes to construct optimal therapeutic strategies and evaluate how they ameliorate the effects of disease. Retinitis pigmentosa (RP) is a family of blinding eye diseases caused by photoreceptor degeneration. The absence of the cells that for this primary signal leads to blindness. My interest in RP involves the evaluation of therapies to restore vision: replacing degenerated photoreceptors either with: (1) new stem or other embryonic cells, manipulated to become photoreceptors or (2) prosthetics devices that replace the photoreceptor signal with an electronic signal to light. Glaucoma is caused by increased intraocular pressure and leads to ganglion cell death, which eliminates the link between the retinal output and central visual processing. We are parsing out of the effects of increased intraocular pressure and aging on ganglion cells. Congenital Stationary Night Blindness (CSNB) is a family of diseases in which signaling is eliminated between rod photoreceptors and their postsynaptic targets, rod bipolar cells. This deafferents the retinal circuit that is responsible for vision under dim lighting. My interest in CSNB involves understanding the basic interplay between excitation and inhibition in the retinal circuit and its normal development. Because of the targeted nature of this disease, we are hopeful that a gene therapy approach can be developed to restore night vision. My work utilizes rodent disease models whose mutations mimic those found in human patients. While molecular manipulation of rodents is a fairly common approach, we have recently developed a mutant NIH miniature swine model of a common form of autosomal dominant RP (Pro23His rhodopsin mutation) in collaboration with the National Swine Resource Research Center at University of Missouri. More genetically modified mini-swine models are in the pipeline to examine other retinal diseases.

Gene Therapy in Epilepsy

Activity-dependent Gene Therapy for Epilepsy

Gene therapy for Optic Neuropathies

Regenerative Neuroimmunology - a stem cell perspective

There are currently no approved therapies to slow down the accumulation of neurological disability that occurs independently of relapses in multiple sclerosis (MS). International agencies are engaging to expedite the development of novel strategies capable of modifying disease progression, abrogating persistent CNS inflammation, and support degenerating axons in people with progressive MS. Understanding why regeneration fails in the progressive MS brain and developing new regenerative approaches is a key priority for the Pluchino Lab. In particular, we aim to elucidate how the immune system, in particular its cells called myeloid cells, affects brain structure and function under normal healthy conditions and in disease. Our objective is to find how myeloid cells communicate with the central nervous system and affect tissue healing and functional recovery by stimulating mechanisms of brain plasticity mechanisms such as the generation of new nerve cells and the reduction of scar formation. Applying combination of state-of-the-art omic technologies, and molecular approaches to study murine and human disease models of inflammation and neurodegeneration, we aim to develop experimental molecular medicines, including those with stem cells and gene therapy vectors, which slow down the accumulation of irreversible disabilities and improve functional recovery after progressive multiple sclerosis, stroke and traumatic injuries. By understanding the mechanisms of intercellular (neuro-immune) signalling, diseases of the brain and spinal cord may be treated more effectively, and significant neuroprotection may be achieved with new tailored molecular therapeutics.

Towards targeted therapies for the treatment of Dravet Syndrome

Dravet syndrome is a severe epileptic encephalopathy that begins during the first year of life and leads to severe cognitive and social interaction deficits. It is mostly caused by heterozygous loss-of-function mutations in the SCN1A gene, which encodes for the alpha-subunit of the voltage-gated sodium channel (Nav1.1) and is responsible mainly of GABAergic interneuron excitability. While different therapies based on the upregulation of the healthy allele of the gene are being developed, the dynamics of reversibility of the pathology are still unclear. In fact, whether and to which extent the pathology is reversible after symptom onset and if it is sufficient to ensure physiological levels of Scn1a during a specific critical period of time are open questions in the field and their answers are required for proper development of effective therapies. We generated a novel Scn1a conditional knock-in mouse model (Scn1aSTOP) in which the endogenous Scn1a gene is silenced by the insertion of a floxed STOP cassette in an intron of Scn1a gene; upon Cre recombinase expression, the STOP cassette is removed, and the mutant allele can be reconstituted as a functional Scn1a allele. In this model we can reactivate the expression of Scn1a exactly in the neuronal subtypes in which it is expressed and at its physiological level. Those aspects are crucial to obtain a final answer on the reversibility of DS after symptom onset. We exploited this model to demonstrate that global brain re-expression of the Scn1a gene when symptoms are already developed (P30) led to a complete rescue of both spontaneous and thermic inducible seizures and amelioration of behavioral abnormalities characteristic of this model. We also highlighted dramatic gene expression alterations associated with astrogliosis and inflammation that, accordingly, were rescued by Scn1a gene expression normalization at P30. Moreover, employing a conditional knock-out mouse model of DS we reported that ensuring physiological levels of Scn1a during the critical period of symptom appearance (until P30) is not sufficient to prevent the DS, conversely, mice start to die of SUDEP and develop spontaneous seizures. These results offer promising insights in the reversibility of DS and can help to accelerate therapeutic translation, providing important information on the timing for gene therapy delivery to Dravet patients.

Gene therapy in neuromuscular and mitochondrial disorders

AAV-mediated gene therapy for neurological disorders

Gene Therapy for Neurodegeneration

One of the major challenges in developing therapeutics for the neurodegenerative disorders is the blood-brain barrier, limiting the availability of systemically administered therapies such as recombinant proteins or monoclonal antibodies from reaching the brain. Direct central nervous system (CNS) gene therapy using adeno-associated virus vectors expressing a therapeutic protein, monoclonal antibody or inhibiting RNA-coding sequences has two characteristics ideal for therapy of neurodegenerative disorders: circumventing the blood-brain barrier by directly expressing the therapy in the brain and the ability to provide persistent therapy with only a single administration. There are several critical parameters relevant to successful CNS gene therapy, including choice of vector, design of the gene to be expressed, delivery/route of administration, dose and anti-vector immune responses. The presentation will focus on these issues, the current status of clinical trials of gene therapy for neurodegeneration and specific challenges that will need to be overcome to ensure the success of these therapies.

Understanding how photoreceptor degeneration alters retinal signaling, and how to intervene to rescue vision

Age-related Macular Degeneration (AMD) and Retinitis Pigmentosa (RP) are vision disorders caused by loss of rod and cone photoreceptors, but downstream retinal neurons also show physiological and morphological changes, resulting in the emergence of hyperactivity and rhythmic firing in many retinal ganglion cells (RGC). We recently discovered that retinoic acid (RA) is a key signal that triggers hyperactivity and that blockers of RA unmask light responses in RGCs that would otherwise be obscured. Recent work is revealing where in the retina circuit RA initiates functional changes. Moreover, interfering with the RA signaling pathway with drug or gene therapy can improve spatial vision in a mouse model of RP, providing a new strategy for enhancing low vision in human RP and AMD.

Ex vivo gene therapy for epilepsy. Seizure-suppressant and neuroprotective effects of encapsulated GDNF-producing cells

A variety of pharmacological treatments exist for patients suffering from focal seizures, but systemically administered drugs offer only symptomatic relief and frequently cause unwanted side effects. Moreover, available drugs are ineffective in one third of the patients. Thus, developing more targeted and effective treatment strategies is highly warranted. Neurotrophic factors are candidates for treating epilepsy, but their development has been hampered by difficulties in achieving stable and targeted delivery of efficacious concentrations within the brain. We have developed an implantable cell encapsulation system that delivers high and consistent levels of neurotrophic molecules directly to a specific brain region. The potential of this approach has been tested by delivering glial cell line-derived neurotrophic factor (GDNF) to the hippocampus of epileptic rats. In vivo studies demonstrated that these intrahippocampal implants continue to secrete GDNF and produce high hippocampal GDNF tissue levels in a long-lasting manner. Identical implants rapidly and greatly reduced seizure frequency in the pilocarpine model. This effect increased in magnitude over 3 months, ultimately leading to a reduction of spontaneous seizures by more than 90%. Importantly, these effects were accompanied by improvements in cognition and anxiety, and by the normalization of many histological alterations that are associated with chronic epilepsy. In addition, the antiseizure effect persisted even after device removal. Finally, by establishing a unilateral epileptic focus using the intrahippocampal kainate model, we found that delivery of GDNF exclusively within the focus suppressed already established spontaneous recurrent seizures. Together, these results support the concept that the implantation of encapsulated GDNF-secreting cells can deliver GDNF in a sustained, targeted, and efficacious manner. These findings may form the basis for clinical translation of this approach.

AAV gene therapy delivering recombinant dimeric peptides targeting PICK1 fully relieve chronic neuropathic pain

Astrocyte-based interleukin-2 gene therapy in temporal lobe epilepsy

FENS Forum 2024

AAV-mediated gene therapy for sensory regeneration after spinal cord injury

Anti-NKCC1 gene therapy rescues cognitive deficits in a mouse model of Down syndrome

Autologous haematopoietic stem cell gene therapy for people with Friedreich’s ataxia

E2F4DN-based gene therapy recovers long-term potentiation and hippocampal-dependent memory in homozygous 5xFAD mice

Folate receptor α positive hybridosomes as vehicles for non-invasive brain-targeted gene therapy

Gene Therapy Research and the Brain: Is Africa Ethically, Legally and Socially Ready?

Is GDNF dose essential for Parkinson ’s disease gene therapy success?

Gene therapy targeting the blood-brain barrier improves neurological symptoms in a model of genetic MCT8 deficiency

IGF-1 gene therapy on dopaminergic neurons and glial cells interaction in early cognitive deficits in a neurodegenerative animal model

Intravenous gene therapy using AAVPHP.eB for metachromatic leukodystrophy

Targeted gene therapy with FGF22 into subsets of spinal interneurons improves circuit plasticity and functional recovery following spinal cord injury

Towards a cure for Creatine Transporter Deficiency: a Gene Therapy Approach

Blood biomarkers to monitor neuroinflammation: Insights from hematopoietic stem cell transplantation and gene therapy in X-linked adrenoleukodystrophy

FENS Forum 2024

CNS-targeted antioxidant gene therapy for treating epilepsy

FENS Forum 2024

Developing gene therapy vector for the treatment of creatine transporter deficiency syndrome

FENS Forum 2024

Evaluation of optogenetic gene therapy for hearing restoration in in vivo rodent models of sensorineural hearing loss

FENS Forum 2024

A gene therapy approach for focal epilepsy based on GABA\(_A\) receptor overexpression

FENS Forum 2024

Precision gene therapy for Alzheimer's disease: Enhancing amyloid-ß clearance at the brain endothelium with super-selective nanocarriers

FENS Forum 2024