Identification of vulnerable cell types and quantification of cell type-specific differential gene expression in the Pitt-Hopkins Syndrome mouse model

Awardee: Brady Maher

Institution: Johns Hopkins University School of Medicine

Grant Amount: $73,473.00

Funding Period: February 1, 2024 - January 31, 2025

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Summary:

The brain is composed of two major cell types, neurons and glia; however, these two cell classes quickly become very complex as you begin to categorize them into specific subtypes of cells based on their structure and function. For instance, glia cells are comprised of astrocytes, oligodendrocytes, and microglia, which all have unique structures and functions, and these three cell types can be further divided into additional subtypes. This complexity is even greater for neurons, which are first subdivided into excitatory and inhibitory neurons, but then have so many subtypes they cannot all be listed here. Recent technological advances in single cell sequencing (scRNAseq) have emerged that allow us to quantify the expression of genes within individual cell types, which is critically important because each subtype of cell expresses different genes that regulate the specific function of that cell type. Transcription factor 4 (Tcf4), is a transcription factor that regulates expression of specific genes, however the set of genes it regulates, differs depending on the cell type. Currently, there is no data available that describes how disease-causing mutations in TCF4 effects cell type specific expression in the brain. Therefore, we propose to perform scRNAseq on brain samples from the PTHS mouse model and WT littermates. Previous results from our lab and others have shown that Tcf4 is highly expressed during brain development and mutations in Tcf4 result in alterations in the proportions of specific types of cells (e.g., GABAergic interneurons and oligodendrocytes), however we hypothesize this list of vulnerable cell types is not complete. In addition, Tcf4 is expressed throughout the lifespan, where it is continually regulating gene expression in a cell-type dependent manner. Unfortunately, the field currently lacks an understanding of which sets of genes Tcf4 regulates in any specific cell type. Our proposal is designed to fill in these important knowledge gaps and will help to confirm prior observed vulnerable cell types and identify new cell types of risk. In addition, our approach will identify genes that are differentially expressed in specific cell types, which will help to identify genes that can be targeted by cell type-specific therapeutic approaches. We plan to openly share our results with the research community. We believe it will be beneficial to improving emerging gene therapy approaches by informing us about which cell types should be modified. We believe it will serve to identify vulnerable cell types that may in the future be replaced using cell replacement therapies. Lastly, we believe these datasets will be useful for computational approaches that are using artificial intelligence and machine learning paradigms to identify therapeutic targets and predict effective therapeutic compounds.

Unravelling HGprt functioning in fore- and midbrain development using brain organoids

Awardee: Sharon Kolk

Institution: Radboud University, Donders Institute for Neuroscience

Grant Amount: $68,367.00

Funding Period: February 1, 2024 - January 31, 2025

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Summary:

LND is an incapacitating disease characterized by a neurobehavioral phenotype, cognitive deficits and self-injurious behavior caused by HPRT1 gene mutation(s). LND is specifically associated with a reduction of dopamine in the brain. Recently, we reported that proliferation and migration patterns of developing midbrain dopamine (mDA) neurons are disrupted in absence of the gene, resulting in abnormal brain development in an LND animal model. To dissect the role of the causative gene in human fore- and midbrain development, we intend to investigate human-specific brain organoids using patient-derived induced pluripotent stem cell (iPSC) lines carrying HGPRT loss-of-function (LOF) mutations, age-matched control lines as well as edited control lines carrying HGPRT mutations. In addition, assembloids -fusions of dorsal forebrain organoids and midbrain organoids- will be generated in various combinations of control versus LOF tissue at multiple time points. It is furthermore shown that folic acid plays a role in purine metabolism and that physiological levels lead to metabolite accumulation in LND patients. Therefore, we will add various concentrations to the culture medium of both the fore-as well as the midbrain organoids at multiple developmental timepoints. Eventually this will give us insight into the developmental time window where we can, either genetically or pharmacologically, intervene in the future to alleviate particularly the behavioral and/or cognitive characteristics associated with LND.

Development of a validated and patient-specific GNAO1 model for screening and testing of therapeutics

Awardee: Harald Mikkers

Institution: Leiden University Medical Center, Netherlands

Grant Amount: $100,000

Funding Period: September 15, 2023 - September 14, 2024

Summary: This project will advance and improve a state-of-the-art personalized medicine tool for GNAO1. He will use funding from the Bow Foundation to create a validated stem cell GNAO1 model that opens the doors to various drug screening efforts. The work will investigate how GNAO1 impacts neurons and evaluate the suitability of the iPSC-based model for testing of therapeutics and drug responses

Establishing a Krabbe Disease Newborn Screening Biobank and Natural History Database Platform

Awardee: Laura Adang

Institution: Children's Hospital of Philadelphia

Grant Amount: $150,000

Funding Period: August 1, 2023 - July 31, 2024

Testing mechanisms and intervention strategies in GNAO1 dystonia

Awardee: Kirill Martemyanov

Institution: University of Florida Scripps Institute for Biomedical Innovation and Technology

Grant Amount: $100,000

Funding Period: August 1, 2023 - July 31, 2024

Summary: This project will help advance scientific understanding about the mechanisms of dystonia. Many GNAO1 patients suffer from dystonia, commonly known as involuntary muscle movements. Bow Foundation funding will allow Dr. Martemyanov to use a mouse model to shine light on the impact of GNAO1 on dystonia and brain signals while also testing possible treatment strategies.

Personalized Anti-Sense Oligonucleotide Therapy in a Patient with GNAO1 Mutation

Awardee: Jennifer Friedman

Institution: University of California San Diego and Rady Children’s Hospital

Grant Amount: $100,000

Funding Period: August 1, 2034 - July 31, 2024

Summary: Dr. Friedman partnered with the n-Lorem Foundation to support the administration of an experimental antisense oligonucleotide (ASO) medicine that targets the GNAO1 gene. Funding from the Bow Foundation will help Dr. Friedman collect and evaluate the clinical observations of this cutting-edge treatment, including changes in baseline over time and data from predetermined outcome measures. This preclinical work will allow the research team to determine if ASO treatments for other GNAO1 patients are a viable approach for other patients.

Assessment of the therapeutic potential of TATk-hCDKL5 isoform 1 and 2 produced in recombinant Antarctic Pseudoalteromonas haloplanktis TAC125

Awardee: Maria Luisa Tutino, PhD

Institution: University Federico II of Naples

Award Amount: $149,985.00

Funding Period: May 1, 2023 - April 31, 2024

Therapeutic potential of Ca2.3 inhibitors in CDD mouse and human models

Awardee: Marisol Sampedro Castanedo, PhD

Institution: Francis Crick Institute

Award Amount: $149,942.00

Funding Period: May 1, 2023 - April 31, 2024

Clinical trial for antisense oligonucleotide therapy in a patient with ADLD

Awardee: Margot Cousin

Institution: Mayo Clinic

Grant Amount: $50,000

Funding Period: May 1, 2023 - April 30, 2024

Summary: The long-term research goal is to advance disruptive innovation to transform care for individuals with ADLD through the development of a translational therapeutics program using team science. We hypothesize that a gapmer ASO to knockdown LMNB1 expression will be safe and well tolerated and that it will ultimately improve clinical outcomes in patients with ADLD. The objectives in this application are to develop and execute a first-in-human clinical trial to determine safety, tolerability, and potential clinical benefit of an LMNB1-targeted ASO therapy in a single patient with ADLD.

Development of 3D ADLD microfiber and organoid models for studying biomarkers and drug testing

Awardee: Stefano Ratti

Institution: University of Bologna

Grant Amount: $50,000

Funding Period: May 1, 2023 - April 30, 2024

Summary: The project aims at developing reliable ADLD microfiber and organoid models for investigating
biomarkers and for drug testing. The novel models to be developed with this substantial 1 -year funding include 3D microfiber co-cultures of astrocytes and oligodendrocyte precursors (OPCs) and brain organoids. These models will be created from the fibroblasts of patients with the LMNB1 gene duplication and deletion phenotypes and healthy donors.  

Analyzing CNS cell type specific transcriptomics in ADLD

Awardee: Quasar Padiath

Institution: University of Pittsburgh

Grant Amount: $50,000

Funding Period: May 1, 2023 - April 30, 2024

Summary: In this proposal, ADLD brain tissue samples will be utilized to carry out both bulk and
CNS cell type specific transcriptomics (RNA Seq analysis). Such an analysis will identify pathways there are perturbed as a result of lamin B1 overexpression and interrogate lamin B1 overexpression across different CNS cell types. These studies will help identify pathways contributing to the demyelination phenotype that may serve as potential therapeutic targets. In addition, cell type specific analysis can identify cells that are targeted for lamin B1 overexpression and cell type specific pathways that are perturbed providing critical insights into which cell types are responsible for the disease process.

New Drosophila models of CDD

Awardee: Maximo Ibo Galindo, PhD

Institution: Centro de Investigación Príncipe Felipe

Award Amount: $148,950.00

Funding Period: May 1, 2023 - April 31, 2024

Targeted reactivation of ZC4H2 using miniature Cas editors

Awardee: Julian Halmai

Institution: University of California, Davis

Grant Amount: $46,846.00

Funding Period: February 1, 2023 - January 31, 2024

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Summary:

The overall goal of this proposal is to develop CRISPR therapeutics for ZC4H2 Associated Rare Disorders. If successful, reactivation of the X-linked ZC4H2 could result in rescue of disease associated phenotypes in female patients affected by the disorder. This proposal utilizes AAV ready miniature epigenome editors that have great potential to improve the field of extant CRISPR therapeutics.

Structural and Functional Investigation of the ZC4H2 Protein

Awardee: Fahad Ali

Institution: Mohammed Bin Rashid University Of Medicine and Health Sciences

Grant Amount: $46,846.00

Funding Period: February 1, 2023 - January 31, 2024

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Summary:

ZC4H2 Associated Rare Disorders (ZARD) is a rare genetic disorder that impacts the nervous system. It is caused by mutations within the ZC4H2 gene. ZC4H2 codes for a protein that, as of yet, has not been studied and is of unknown function. In this project, we aim to investigate this function using a combination of cellular and molecular approaches to guide future therapeutic development.

Home-monitoring of specific branched chain amino acids

Awardee: Lital Alfonta

Institution: Ben-Gurion University of the Negev

Grant Amount: $71,985.00

Funding Period: February 1, 2023 - January 31, 2024

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Summary:

The project aims at developing a non-invasive home test for immediate monitoring of the orphan condition Maple Syrup Urine Disease (MSUD). MSUD is a serious genetic condition caused by a deficiency or a mutation in the enzyme keto-acid-dehydrogenase. Blood tests show high levels of three amino acids (leucine, isoleucine and valine), that can lead to life-threatening cerebral oedema and dysmyelination in affected individuals. The disease is more common in Ashkenazi Jews, and in the Bedouin population in the South region of Israel. Children with MSUD must remain on a special diet that restricts the consumption of those three amino acids. Currently, the amino acid levels of children with MSUD are monitored weekly at the hospital, and the results arrive only after several days. We propose to develop a technology based on bioelectrochemistry, which combines optimization of protein function with synthetic biology tools in order to create accurate and specific sensors for immediate monitoring of the relevant amino acids. This will enable real-time diet recommendations and forgo the need for a weekly hospital visit. In addition, neonates are routinely scanned for amino acid levels, and the novel technology can supply immediate results. Immediate monitoring of amino acids is especially crucial in the developmental phase of people (i.e. children and neonates).

Development of neuroprotective gene therapy for MSUD

Awardee: John R Counsell

Institution: UCL

Grant Amount: $71,985.00

Funding Period: February 1, 2023 - January 31, 2024

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Summary:

We are seeking to develop a treatment for a severe metabolic disease called Maple Syrup Urine Disease (MSUD) that results from an inability to break down substances that most of us consume daily, when following a normal diet. MSUD patients are at risk of life-threatening brain damage unless they have their diet carefully managed from birth. Even then, patients remain at risk of brain damage during periods of illness, normally due triggered by infections. At University College London, we are developing a potential cure for MSUD using a technique called gene therapy, whereby a set of genes that are defective in MSUD can be restored in relevant parts of the body. However, it is not currently known whether gene therapy needs to be targeted to the brain as part of a curative strategy. Therefore, our research team aim to investigate this, using a mouse model of the disease, with our hypothesis being that brain cells will need to be targeted in order to fully restore healthy brain development during in early childhood.

The TGFβ pathway as a therapeutic target for collagen VI-related muscular dystrophy

Awardee: Payam Mohassel

Institution: Johns Hopkins University

Grant Amount: $113,008.00

Funding Period: February 1, 2023 - January 31, 2024

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Summary:

Mutations in collagen VI cause a spectrum of muscle disease ranging from severe Ullrich congenital muscular dystrophy to the milder Bethlem myopathy. Collagen VI is an integral component of the extracellular matrix. When collagen VI is not functioning properly due to mutations, skeletal muscle will develop weakness, atrophy, degeneration, and fibrosis. We have recently identified alterations in regulation of the TGFβ pathway in human muscle biopsy samples of patients with COL6-related dystrophies (COL6-RD). We have also found a similar alteration of this pathway in a new mouse model of the disease, Col6a2 knockout mice. The overall goal of this project is to help identify novel therapeutic targets in COL6-RD that engage the TGFβ pathway and to test them in the mouse model. We trust that these studies will increase our understanding of this pathway in COL6-RD and pave the way for future studies of therapeutics that target this pathway.

Preclinical assessment of potential drug candidates in Vps13b knockout mice for the treatment of Cohen syndrome

Awardee: Muhammad Ansar

Institution: University of Lausanne

Grant Amount: $100,474.00

Funding Period: February 1, 2023 - January 31, 2024

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Summary:

Cohen Syndrome is a rare genetic disorder caused by mutations in VPS13B gene. Patients suffer from developmental, intellectual, motor, metabolic, immunologic disorders, and visual impairments. Considering the current stage of research on Cohen syndrome and VPS13B, one of the most direct way of looking for treatment possibilities is to attempt drug repurposing of FDA-approved small pharmaceutical compounds. We recently performed a high-throughput microscopy screening assay based on the ability to revert the impaired cellular phenotype (Golgi morphology) of human VPS13B-deficient cells as well as in patients’ fibroblasts. We screened a library of 1280 FDA-approved pharmaceutical compounds, and the top 30 positive hits were further subjected to determine the dose-response. Out of the 30 positive candidates, we selected the four most effective compounds, previously used successfully in mice for the treatment of other pathologies, for which the toxicity is known, the effective dose is low, and there are little to no side effects in both mice and humans. The aim of the proposed project is to assess the treatment potential of the selected four drug candidates in the Cohen syndrome mouse model. In this project, the four selected candidate drugs will be fed to four groups of pregnant mice since the beginning of pregnancy. Drugs will be orally administered by mixing in food pellets. Pups born from these pregnancies will continue receiving the drugs and will be analysed until the age of three months. The treatment efficacy of the potential drug candidates in Vps13b knockout mice will be assessed by observing the most cardinal features of Cohen syndrome in mouse models.

IV Delivery of Ex Vivo Lentiviral Corrected CD34+ Bone Marrow Cells to Treat Systemic Disease in a Canine Model of Mucopolysaccharidosis VI

Awardee: Margret L. Casal

Institution: University of Pennsylvania

Grant Amount: $60,350.00

Funding Period: February 1, 2023 - January 31, 2024

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Summary:

MPS VI causes severe skeletal disease and moderate systemic disease. Our canine model faithfully mimics the disorder in human patients with MPS VI. This projects examines the feasibility of harvesting stem cells from dogs affected with MPS VI, correcting the cells in tissue culture using viral vectors, and then returning the gene therapy corrected cells back to the affected neonatal dog. These experiments will show that this form of therapy is safe and effective, while not having the side effects of bone marrow transplantation (graft rejection, host versus graft disease, lifelong immunosuppression) or enzyme replacement therapy (repeated administration, expense, inability to correct bone disease).

Preclinical study of Fluoxetine efficacy in MPS-I mouse model

Awardee: NICOLINA CRISTINA SORRENTINO

Institution: FONDAZIONE TELETHON ETS-TIGEM

Grant Amount: $60,000.00

Funding Period: February 1, 2023 - January 31, 2024

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Summary:

Mucopolysaccharidosis type I (MPS-I) is a severe inherited disorder characterized by deficient activity of lysosomal enzyme α-L-Iduronidase (IDUA) responsible for the degradation of the glycosaminoglycans, leading to systemic symptoms and a shortened lifespan. Current therapies are mainly palliative with no benefit for the brain pathology. Several works indicated the importance of the lysosomal and autophagy alterations as major players in the development of brain and peripheral tissue pathology in Lysosomal Storage Disorders (LSD). Importantly, in our recent work we combined automated microscopy screening and repurposing of FDA compounds to identify approved drugs able to correct lysosomal dysfunction in LSD. Our drug survey resulted in the identification of Fluoxetine, a central nervous system drug and one of the most prescribed medicines in adults and children. Interestingly, we showed that Fluoxetine boosts lysosomal function and promotes glycosaminoglycans degradation in MPS-IIIA, MPS-I and MSD cell lines. Furthermore, our recent preclinical study demonstrated the effectiveness of Fluoxetine in the amelioration of brain and somatic pathological hallmarks of MPS-IIIA such as the accumulation of storage materials, inflammation, and slow-down cognitive deterioration in MPS-IIIA mouse model. Based on these promising results, we propose to validate the effectiveness of the Fluoxetine administration for the treatment of brain and peripheral pathology in a mouse model of MPS-I.