Determination of pathomechanisms and assessment of therapeutic strategies for Cohen Syndrome in patient derived cells and a murine model

Awardee: Muhammad Ansar

Institution: Jules-Gonin Eye Hospital, Ophthalmology Department of the University of Lausanne, Lausanne, Switzerland

Grant Amount: $$115,000

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

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Summary:

Cohen Syndrome (CS) is a rare genetic disease caused by the loss of function of the gene called VPS13B. Individuals with CS suffer from developmental, intellectual, motor, metabolic, immunologic and progressive vision loss problems. In this project we proposed to study and understand how the VPS13B gene functions and how the loss of this gene causes the disease symptoms. At the same time we’ll try to explore and test various treatment options by using cellular and mouse models, with the aim to ultimately find the cure for the CS disease or to at least stop the progressive loss of vision in these patients. Treatment strategies include the use of chemical drugs as well as gene therapy.

High Resolution Ventilation and Perfusion MRI Assessment of Neuroendocrine Cell Hyperplasia of Infancy (NEHI) in Infants and Young Children: Technical Feasibility and Direct Clinical Application

Awardee: Katie Krone

Institution: Boston Children's Hospital

Grant Amount: $41,000

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

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Summary:

Neuroendocrine cell hyperplasia of infancy (NEHI) is a type of childhood lung disease that is very challenging to diagnose because of the lack of specific disease features. Clinical and radiologic features may overlap with other types of lung disease affecting children. Currently, clinicians rely on imaging with high-resolution chest computed tomography (HRCT) and/or tissue diagnosis by surgical lung biopsy in order to identify NEHI in patients who have suggestive clinical signs and symptoms. This diagnostic approach poses risks to the vulnerable pediatric population. HRCT exposes infants and children to potentially harmful ionizing radiation, and often requires sedation to obtain adequate images in younger children. There are also some concerns about the effects of general anesthesia on the developing brain. An additional problem is that HRCT scans are often not specific enough to be diagnostic of NEHI. Given the potential risks of exposure to radiation and anesthesia, and the limitations of HRCT interpretation, new diagnostic strategies are needed that provide insight into the pathophysiology of NEHI, ensure timely, safe and accurate diagnostic information, and improve patient care. High-resolution ventilation and perfusion MRI is new attractive alternative that overcomes the limitations and risks of HRCT and has the potential to provide improved diagnostic information. Thus, the main objective of this study is to prospectively investigate the technical feasibility and clinical utility of high-resolution ventilation and perfusion MRI in infants and young children with clinically suspected or confirmed NEHI.

Spatial Transcriptomics to Identify Cellular Alterations in NEHI

Awardee: W. Adam Gower

Institution: University of North Carolina at Chapel Hill School of Medicine

Grant Amount: $41,000

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

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Summary:

The diagnosis and management of NEHI is complicated by a lack of understanding about the biologic processes at work in the lungs of affected children. Research so far has suggested that NEHI is unique from other forms of childhood interstitial lung disease, and likely involves abnormal function of neuroendocrine cells and other cell types in the smallest airways. We propose to utilize a new technology that will allow use to determine what genetic pathways and biological processes are unique to NEHI lung tissue, using excess lung biopsy material that has already been collected and banked. By understanding which genetic pathways and processes are unique to NEHI compared to children with other lung diseases and healthy controls, we may identify ways to improve diagnosis and perhaps targets for new and unique treatments. Our team has extensive expertise in NEHI and rare lung disease research, access to tissues samples for use, and colleagues who can assist in the analyses needed to complete this project during the award period.

Targeting mTOR signaling to improve neurologic outcomes in MSUD

Awardee: Rebecca Ahrens-Nicklas

Institution: The Children's Hospital of Philadelphia and The University of Pennsylvania

Grant Amount:

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

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Summary:

Maple Syrup Urine Disease arises from a defect in branched chain amino acid metabolism (BCAA), that leads to toxic increases in certain amino acids throughout the body. Dietary therapy and liver transplantation can improve levels of BCAAs; however, unfortunately, patients still have neurocognitive and psychiatric symptoms. Based on work in a mouse model of MSUD, we believe that an inability to use BCAAs as fuel in the brain changes mTOR signaling, an important pathway for neurodevelopment. Other disorders with abnormal mTOR activation are known to result in learning difficulties and psychiatric symptoms. In this application, we plan to study how abnormal mTOR signaling affects the brain in MSUD and to explore new therapeutic approaches aimed at correcting this difference.

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.

ASO therapy in CDKL5 deficiency disorder

Awardee: Michela Fagiolini, PhD

Institution: Boston Children's Hospital

Award Amount: $150,000

Funding Period: May 1, 2021 - April 31, 2022

Comparison of Brain Biodistribution of Two CDKL5 Gene Therapy Vector Leads

Awardee: Dolan Sondhi, PhD

Institution: Weill Cornell Medicine

Award Amount: $150,000

Funding Period: May 1, 2021 - April 31, 2022

Advancing a mosaic CDKL5 zebrafish model for high-throughput screening approaches

Awardee: Christopher McGraw, MD, PhD

Institution: Boston Children's Hospital

Award Amount: $150,000

Funding Period: May 1, 2021 - April 31, 2022

Defining ciliary signaling and targets in CDKL5 Deficiency Disorder

Awardee: Peter K. Jackson, PhD

Institution: Stanford University School of Medicine

Award Amount: $150,000

Funding Period: May 1, 2021 - April 31, 2022

Impact of Cdkl5 deficiency on cortical dynamics and network architecture

Awardee: Michael J. Higley, MD, PhD

Institution: Yale University

Award Amount: $150,000

Funding Period: May 1, 2021 - April 31, 2022

Systems Analysis of the CDKL5-Deficiency Disorder (CDKL5-DD) Cerebrospinal Fluid Proteome

Awardee: Victor Faundez, MD, PhD

Institution: Emory University

Award Amount: $150,000

Funding Period: May 1, 2021 - April 31, 2022

Spatial profiling of scRNAseq signatures in human parathyroid glands

Awardee: Julie Ann Sosa

Institution: University of California at San Francisco

Grant Amount: $50,000

Funding Period: April 1, 2021 - March 31, 2022

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The objectives of this project were to: (1) utilize transcriptomic methods to define individual cell types within the human parathyroid, and (2) employ digital spatial profiling to visualize the localization of these cell types within the native parathyroid gland architecture. The developmental pilot phase work supported by the grant enabled us to establish a solid foundation of procedural optimization and proof of concept data for scaling our single cell sequencing efforts to a larger, more broadly representative cohort of donor parathyroid glands. 

The scientific objectives completed during the one-year project period are essential for comprehensive mapping of the human parathyroid gland.  The specific landmarks achieved include: demonstration that our live organ procurement work flow preserves tissue viability and maintains intact biochemical function; validation of recovery efficiency, parathyroid marker expression and cellular integrity in suspension; comparative assessment of whole cell vs nuclear isolation for downstream molecular analysis; validation of a novel split-pool sequencing approach that greatly improves capture efficiency, reduces selective recovery bias, and eliminates library construction batch effect concerns; digital spatial profiling of archived normal parathyroid gland sections to demonstrate the capture and whole transcriptome interrogation of specific cellular subsets demarcated by marker gene expression; and the molecular data from these studies showing that the cellular composition and transcriptional profiles of parathyroid gland tissue are dynamic rather than static.  This last finding reveals that the cellular content and biochemical activity of the parathyroid gland may be physiologically conditional, suggesting that functional reconstitution of the parathyroid gland is not a fixed target, but instead requires complementation of adaptive capacity in addition to terminally differentiated cellular phenotypes.  These key data will inform future and ongoing studies to reconstitute native parathyroid gland function.

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Publication:

Digital spatial profiling of human parathyroid tumors reveals cellular and molecular alterations linked to vitamin D deficiency

Chia-Ling Tu, Wenhan Chang, Julie A Sosa, James Koh

PNAS Nexus, Volume 2, Issue 3, March 2023, pgad073

Deciphering the structural consequences of ZC4H2 germline rare variants

Awardee: Prof. Michal Linial

Institution: The Hebrew University of Jerusalem

Award Amount: $50,000

Funding Period : January 1, 2021 - December 31, 2021

Studies on ZC4H2 to help better understand the pathophysiology of ZARD

Awardee: Vera Kalscheuer, PhD

Insitution: Max Planck Institute for Molecular Genetics

Award Amount: $50,000

Funding Period: January 1, 2021 - December 31, 2021

Nucleic acid binding by ZC4H2

Awardee: Daniel Dominguez, PhD

Institution: UNC at Chapel Hill

Award Amount: $50,000

Funding Period: January 1, 2021 - December 31, 2021

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Summary:

Mutations or genetic rearrangements in the protein, ZC4H2, cause a group of X-linked neurodevelopmental disorders for which there are no treatments. While the importance of this protein is clear, the specific function of ZC4H2 is still unknown. ZC4H2 is predicted to be a zinc-finger protein. We hypothesize that like many other zinc-finger proteins, ZC4H2 directly binds DNA or RNA, and functions to regulate gene expression programs required for normal development. Our goal is to determine if ZC4H2 interacts with nucleic acids and to identify specific genes and/or gene expression pathways that become dysfunctional when ZC4H2 is mutated. Patients suffering from ZC4H2-associated rare disorders have little recourse; understanding the biological function of this protein is a critical and necessary first step to uncover potential therapeutic approaches.