Pre-clinical investigation of candidate therapies for NUBPL disease

Awardee: Neal Mathew

Institution: Children's Hospital of Philadelphia

Grant Amount: $50,198

Funding Period: February 1, 2022 - January 31, 2023

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Summary:

The overall goal of this project is to identify lead therapeutic candidates for NUBPL-/- based mitochondrial disease. We hypothesize that therapeutic modeling of NUBPL-/- genetic disease across 3 evolutionarily distinct models will enable identification and optimization of a lead therapeutic regimen to prioritize as a precision medicine that improves health in human NUBPL-/- disease patients.

Untargeted metabolomics to map defects arising in Snyder-Robinson syndrome

Awardee: Ankur Jain

Institution: Whitehead Institute for Biomedical Research

Grant Amount: $74,691

Funding Period: February 1, 2022 - January 31, 2023

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Summary:

Snyder-Robinson syndrome (SRS) is a rare, X-linked genetic disorder caused by mutations in the spermine synthase (SMS) gene. In this project, we will examine how this mutation changes the small molecule metabolite composition of the cell. This work may reveal new disease biomarkers, and may potentially inform intervention strategies.

Measuring neurotransmitter metabolites for biomarker discovery in Mucolipidosis IV

Awardee: Yulia Grishchuk

Institution: MGH

Grant Amount: $64,335

Funding Period: February 1, 2022 - January 31, 2023

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Summary:

Mucolipidosis IV (MLIV) is an ultra-rare lysosomal disorder resulting from inactivating mutations in the MCOLN1, the gene encoding the lysosomal cation channel TRPML1. Patients typically present in the first year of life with delayed developmental milestones and reach a plateau in function roughly equivalent to the 18-20 month-old level. In contrast to other lysosomal disorders, patients with MLIV exhibit a relatively stable clinical course before early adolescence with neurological deterioration first emerging after puberty. Recently, we reported a novel TRPML1 gene replacement strategy that restored motor function when administered to either presymptomatic, newborn MLIV mice or symptomatic mice at 2 months of age. Excitingly, these data suggest that TRPML1 gene therapy may be able to restore motor development in patients with MLIV rather than simply delaying disease progression. However, the time needed for restored developmental processes to produce a clinically meaningful improvement in function in humans is uncertain and will likely exceed the 1 year time period in which traditional FDA approved trials require demonstration of efficacy. As such, there is now a critical unmet need for a clinically tractable biomarker to measure TRPML1 activity restoration in the brain. The goal of this proposed study is to determine whether loss of TRPML1 activity alters neurotransmitter metabolite levels in humans and mice with mucolipidosis IV, aiming to develop a therapeutic biomarker for AAV based gene replacement therapy.

Ace-tRNA readthrough therapy for choroideremia caused by nonsense mutations

Awardee: David M. Gamm

Institution: University of Wisconsin-Madison

Grant Amount: $64,360

Funding Period: February 1, 2022 - January 31, 2023

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Summary:

Choroideremia is a devastating eye disease that leads to progressive loss of vision in 1 in 50,000 males. Currently, there are no approved treatments available for individuals affected by choroideremia. While several research laboratories are working on identifying effective therapies, such work is challenged by the lack of appropriate disease models that would allow clear assessment of the efficacy of a potential therapy. To overcome this impediment, the Gamm lab has developed induced pluripotent stem cell (iPSC)-derived retinal cell and organoid models, which provide a powerful platform for therapeutic testing. As in many other inherited disorders, choroideremia is commonly caused by “nonsense” mutations that prevent formation of full-length functional proteins. The Ahern lab has designed a specialized molecule that allows read-through of many types of these mutations, resulting in full-length protein production. Our goal is to test these read-through molecules in iPSC-derived retinal pigmented epithelial cells and photoreceptors affected by choroideremia in order to advance a new type of therapy for a significant portion of choroideremia patients.

Single-nuclei RNA-seq for CADASIL understanding and therapeutic target discovery

Awardee: Israel Fernández Cadenas

Institution: Fundació Privada Institut de Recerca de l’Hospital de la Santa Creu i Sant Pau

Grant Amount: $60,228

Funding Period: February 1, 2022 - January 31, 2023

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Summary:

The aim of this project is to understand the reason why CADASIL is produced, and possible factors associated with the severity of the disease. To do this, we will use a new and innovative strategy with omic technology (single-nuclei RNA-seq analysis) to obtain transcripts and pathways associated with the disease and its severity. Based on this information, we purpose to find therapeutic targets overexpressing/inhibiting the molecules found to be significant in the single-nuclei RNA-seq study and those found significant in other omic studies of CADASIL already published, to evaluate later the benefits in our human cellular model (pattern of aggregation of Notch3).

Modelling CADASIL with patient iPSC-based 3D vessel-on-chip

Awardee: Saskia Lesnik-Oberstein

Institution: Leiden University Medical Center

Grant Amount: $60,228

Funding Period: February 1, 2022 - January 31, 2023

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Summary:

CADASIL is an hereditary small vessel disease caused by mutations in the NOTCH3 gene. These mutations lead to progressive changes in small brain arteries and reduced blood flow to the brain. Patients with CADASIL suffer from strokes and vascular dementia from mid-adulthood. It has recently been shown by our research group, that some NOTCH3 mutations lead to a much earlier onset of CADASIL than other mutations, but why this is the case is not yet understood. CADASIL vessel models representing both severe and mild mutations will enable us to study the molecular mechanisms underlying these differences and will teach us about CADASIL disease pathomechanisms in general. Our university medical center is a CADASIL expert center and for this project we will collaborate with the internationally leading vessel model group in our research center. Together, we will develop 3D CADASIL vessels-on-chip, built up of CADASIL vascular cells. These cells are obtained by harvesting pluripotent stem cells from blood samples of CADASIL patients with different mutations. The stem cells are then differentiated into vascular cells and incorporated into the chips. We will examine structural and functional abnormalities of the vessel wall and the differences between vessels with severe and mild mutations. We aim to share these CADASIL vessel-on-chip with the international CADASIL research community to promote CADASIL research.

DYSTRO-SMARTY: A novel nanotechnology platform for delivery of nucleic acids to treat Collagen VI-related Congenital Muscular Dystrophy

Awardee: Cecilia Jimenez-Mallebrera

Institution: Hospital Sant Joan de Deu

Grant Amount: $48,876

Funding Period: February 1, 2022 - January 31, 2023

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Summary:

Nucleic-Acid based therapies are being developed at a fast pace with 11 currently approved products and many more in the pipeline. However, delivering therapeutic amounts of these nucleic acids to the target tissue remains the major hurdle, particularly for muscle diseases. Here we propose to apply a validated nanotechnology platform, SMARTY, based on non-liposomal lipid-based nanovesicles, called Quatsomes, to deliver nucleic acids to treat COL6-related Congenital Muscular Dystrophy (COL6-CMD). These nucleic acids are antisense oligonucleotides (ASO) that we have designed and tested to correct a common mutation in collagen VI genes. ASO will be conjugated to the Quatsomes and their physico-chemical properties, distribution and integrity inside the cell as well as their specificity and efficacy to correct collagen VI mutations will be systematically investigated in cells from COL6-CMD patients. The Quatsomes platform (patent WO/2020/229469), developed by our collaborators (at VHIR and ICMAB-CSIC), has already been exploited for other applications for effective intracellular delivery of nucleic acids. Moreover, Quatsomes will be produced by a GMP compliant manufacturing process. This will facilitate the future translation and approval of this potential therapy by regulatory agencies bringing COL6-RD closer to Clinical Trial Readiness.

Studying in-situ, in-vivo, and in-silico the pleiotropic action of collagen-VI to identify potential late-onset risks in COL6-CMD patients

Awardee: Jeanette Erdmann

Institution: Universität zu Lübeck

Grant Amount: $48,876

Funding Period: February 1, 2022 - January 31, 2023

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Summary:

Due to better healthcare, COL6-CMD patients have a significantly longer life expectancy today than a few decades ago. For future health management of these patients early recognition of potential late-onset disease risks such as aneurysms, cardiovascular, and intestinal diseases can be vital. We will make use of col6a2 KO zebrafish (by morpholino antisense oligonucleotides) to comprehensively study the pleiotropic action of collagen-VI. Moreover, we will leverage human genetic data from UK biobank to identify by phenome-wide association study associations between genetic variants in COL6A2 gene and potential disease risks. Both strategies may help us to identify potential late-onset risks in COL6-CMD patients.

Rescuing oligodendrogenesis and myelination as possible treatment for Pitt-Hopkins patients

Awardee: Simone Mesman

Institution: Swammerdam Institute of Life Sciences, University of Amsterdam

Grant Amount: $78,530

Funding Period: February 1, 2022 - January 31, 2023

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Summary:

In the brain of Pitt-Hopkins patients myelination, fatty sheets surrounding axons of neurons, is affected. The correct construction of these myelin sheets is crucial for proper brain functioning and neuronal communication. Incorrect myelination generally results in affected brain functioning and could be an underlying cause for defects in brain functioning as detected in PTHS. We propose to study myelination under inflence of PTHS-related Tcf4 mutations, by investigating myelination profiles in PTHS patients and by studying the effects of these mutations on oligodendrogenesis, the generation of oligodendrocytes the cell-type that produces myelin.

Multiplex analysis of variant effects for SLC2A1 gene

Awardee: Christina Gurnett

Institution: Washington University, St Louis

Grant Amount: $64,465

Funding Period: February 1, 2022 - January 31, 2023

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Summary:

The goal of this research is to quantitatively determine the functional impact of all possible genetic variants in SLC2A1 and construct algorithms to accurately predict disease onset and severity correlating through calibration with known pathogenic and benign variants. Toward this goal, we propose to employ a high-throughput framework to assess the functional impact of genetic variants in the SLC2A1. We will introduce hundreds of SLC2A1 variants individually into the haploid cell line (HAP1) via multiplex homology-directed-repair (HDR) using CRISPR and a donor library, so that each cell obtains a single variant knocked into the endogenous SLC2A1 gene. Damaging variants that completely disrupt SLC2A1 function (and glucose uptake) will result in impaired cell growth and will drop out of a population of cells sequenced at different time points. We have preliminary data demonstrating the utility of this approach to quantify the functional effects of 15 SLC2A1 variants. We now propose to scale this assay to generate comprehensive, quantitative functional data for the entire SLC2A1 coding region.

Discovery of glycogen synthase inhibitors for validation as a novel therapeutic target for adult polyglucosan body disease (APBD)

Awardee: Wyatt Yue

Institution: Newcastle University, UK

Grant Amount: $99,025

Funding Period: February 1, 2022 - January 31, 2023

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Summary:

Adult polyglucosan body disease is caused by a defective gene encoding glycogen branching enzyme GBE1, resulting in its low activity. The GBE1 enzyme is essential for making glycogen very compact inside the cell, otherwise the glycogen that is being synthesised by another enzyme glycogen synthase GYS1 will form clogging clumps. Drug development programmes for APBD and related diseases have largely sought to deliver an artificial version of the GBE1 gene, or turn down the native GYS1 gene, both emerging gene therapy approaches that remain experimental and costly for the long run. Our vision is to develop a daily pill for APBD patients as a transformative oral therapy. In the first step towards this goal, we aim to develop small molecules that act on the GYS1 enzyme as a drug starting point. To achieve this, we will take advantage of our unique knowledge about the shape of GYS1 enzyme, as well as cutting-edge computational and screening methods to find small molecules.

Discovery of new therapies for hypertrophic cardiomyopathy in RASopathies using an innovative hiPSC-based high-throughput drug screening platform

Awardee: Fabrice Jaffré

Institution: Weill Cornell Medical College

Grant Amount: $75,431

Funding Period: February 1, 2022 - January 31, 2023

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Summary:

Children with RASopathies often present with severe cardiomyopathies and have a 22% mortality rate by the end of the first year of life. Currently, no specific treatment exists for RASopathy children with hypertrophic cardiomyopathy, therefore there is an urgent need to identify novel therapeutic strategies. The overall goal of this proposal is to uncover innovative therapeutic approaches using human induced pluripotent stem cell-derived cardiomyocytes as a RASopathy disease model and as innovative human 2D and 3D high-throughput drug screening platforms. Completion of this proposal will identify therapeutic molecules for RASopathy children with hypertrophic cardiomyopathy at an unparalleled speed.

EXPLOITING NEURONS- AND BRAIN-DERIVED EXOSOMES AS BIOMARKER FOR CDKL5 DEFICIENCY DISORDER

Awardee: Maurizio Giustetto

Institution: Univ. of Torino - Dept. of Neuroscience

Grant Amount: $75,000

Funding Period: February 1, 2022 - January 31, 2023

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Summary:

The identification of objectively measurable parameters is urgently needed to speed up the diagnosis of CDKL5 deficiency disorder (CDD) and to evaluate the outcomes of both pre-clinical and clinical trials. Although exosomes, nanovescicles seceted by all cell types, can be exploited as unbiased, quantitative and non-invasive biomarker for clinical diagnosis, so far, no information is available on the molecular profile of exosomes in CDD. The goal of our proposal is to fill this gap and by establishing and validating a novel molecular, reliable biomarker for CDD patients.

Understanding RASopathies to better inform diagnosis and treatment.

Awardee: Vanessa Fear

Institution: The University of Western Australia

Award Amount: $69,885

Funding Period: February 1, 2021 - January 31, 2022

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Summary:

The RASopathies are a set of syndromes that include cardiofaciocutaneous (CFC) Syndrome, Noonan Syndrome, Noonan Syndrome with lentigines, and Costello Syndrome.  The syndromes are characterised by overlapping disease phenotype and there is a need to distinguish the different RASopathies in order to facilitate accurate patient diagnosis and identify better treatments. In this study we compare changes in patient DNA (genetic variants) that are causative of CFC and Noonan Syndrome. Further, we investigate a potential disease causing patient genetic variant to determine if they have CFC or Noonan Syndrome. The study harnesses gene editing technology to introduce genetic variants into stem cells, which are then matured into nerve cells. The nerve cell maturation process is monitored to identify syndrome-specific changes to inform syndrome classification in the patient, and to provide a better understanding of both CFC and Noonan Syndrome.

Targeting muscle stem cells for the treatment of Collagen VI muscular dystrophies

Awardee: Nicholas Dumont

Institution: CHU Sainte-Justine research center (University of Montreal)

Award Amount: $42,406

Funding Period: February 1, 2021 - January 31, 2022

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Summary:

Mutations in one of the genes encoding for Collagen VI cause Ullrich muscular dystrophy (severe form) or Bethlem myopathy (milder form). These rare genetic diseases are characterized by progressive muscle weakness and degeneration, which can lead to functional incapacities such as impaired or delayed walking. The effect of collagen VI deficiency on muscle degeneration has been characterized; however, its impact on muscle stem cells, the engine of muscle repair, is unknown. Therefore, the overall goal of this project is to investigate if the myogenesis capacity (formation of new muscle tissue) of muscle stem cells is affected by the lack of collagen VI. We will collect samples from patients affected by collagen-VI muscular dystrophies to study muscle stem cell defects in vitro. Moreover, we will use a 3D muscle-in-a-dish system to screen for therapeutic drugs that enhance the myogenesis capacity of muscle stem cells. Overall, this project will provide a better comprehension of this rare muscular disease, and it will open the way to new therapeutic avenues.

Novel tools for drug repurposing in COL6 myopathies: accelerating the route towards therapy.

Awardee: Paolo Bonaldo

Institution: University of Padova, Department of Molecular Medicine

Award Amount: $42,406

Funding Period: February 1, 2021 - January 31, 2022

Global Registry for Inherited Neuropathies (GRIN) - Natural History Study Data Assessment of Charcot-Marie-Tooth (CMT) Patients (age 3-25) to Support Virtual Clinical Studies

Awardee: Florian Thomas

Institution: Hackensack University Medical Center

Award Amount: $55,090

Funding Period: February 1, 2021 - January 31, 2022

Role of CTHRC1 in the Pathogenesis and Therapy of LAM

Awardee: Elizabeth Henske

Institution: BWH

Award Amount: $70,769

Funding Period: February 1, 2021 - January 31, 2022

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Summary:

This project is focused on a protein, CTHRC1 (collagen triple-helix repeat containing 1), that has never before been studied in LAM.  CTHRC1 is a protein that is usually secreted by cells and can be detected in the blood.  In other diseases, CTHRC1 is linked to the rate of cellular growth, and in several types of cancer, a high level of CTHRC1 in the blood is associated with a poor clinical prognosis.  

 In a new line of investigation in our lab, Dr. Nico Alesi has discovered that levels of CTHRC1 are elevated in cellular models of LAM.  CTHRC1 is also increased in human angiomyolipomas and in LAM cells.   Interestingly, levels of CTHRC1 are not suppressed by Rapamycin.  In TSC2-deficient cells, inhibition of CTHRC1 decreases cell growth. 

 These data suggest that CTHRC1 is a newly recognized driver of LAM cell growth.  Because levels of CTHRC1 are not affected by the mTOR inhibitor Rapamycin, CTHRC1 could help to explain why LAM cells are not eliminated during therapy with mTOR inhibitors.  Identifying therapeutic strategies to eliminate LAM cells is a key goal of this work. 

REACT: a reversible knock-out mouse model to explore treatment strategies for the SETBP1 haploinsufficiency disease

Awardee: Rocco Piazza

Institution: University of Milano - Bicocca

Award Amount: $40,373

Funding Period: February 1, 2021 - January 31, 2022

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Summary:

The SETBP1 gene is located on chromosome 18q21.1; it encodes for a protein of 1596 residues with a predicted molecular weight of 170 kD and a predominantly nuclear localization. Genetic abnormalities occurring in the SETBP1 gene are responsible for the onset of two different disorders: 1) SETBP1 haploinsufficiency (SH), a disorder characterized by varying degrees of intellectual disability, developmental as well as speech delays and caused by sub-megabase deletions occurring in SETBP1 locus. 2) Schinzel-Giedion Syndrome (SGS), a rare disease with multiple severe congenital malformations and fatal outcome, caused by de novo, single nucleotide SETBP1 mutations. The pathogenic mechanisms responsible for the onset of SH and SGS are probably tightly connected albeit opposite, as SH is caused by a decrease in SETBP1 protein while SGS is caused by its accumulation. The involvement of the central nervous system in both disorders suggests that SETBP1 itself plays a critical role in this context. Here, we propose to generate and to functionally validate a reversible knock-out mouse model for the SH syndrome. In this model, a blocking cassette flanked with loxP recombination sites would be inserted at intron level in the normal Setbp1 locus by homologous recombination, resulting in a mouse that is unable to express Setbp1 at normal level, therefore mimicking the human SH condition. Then, the usage of specific Cre mouse lines, where the recombinase is either expressed starting from the embryo, only in the adult, or is tamoxifen-inducible, would allow the removal of the blocking cassette and reactivation of the Setbp1 expression at normal levels.

The project herein presented will provide insightful information on the molecular consequences of the reactivation of SETBP1 protein in a knock-out/haploinsufficient model that mimic the SH syndrome. Our new in vivo model will constitute a valuable platform to dissect the molecular mechanisms at the basis of the brain damage following SETBP1 haploinsufficiency and, even more importantly, to study the effect of SETBP1 reactivation at different time-points during the life of the mouse model.

Neuromodulation of prefrontal circuits in a mouse model of SETBP1 disorder

Awardee: Audrey Brumback

Institution: The University of Texas at Austin

Award Amount: $40,373

Funding Period: February 1, 2021 - January 31, 2022