2020

Received from Dr. Joe and Dorothy January 2020

********

With the support of cureCADASIL funding in 2019, my laboratory has now successfully trained a postdoctoral fellow, Dr. Dorothee Schoemaker, to conduct blood biomarkers analysis. The larger aim of this work is to identify an accessible, sensitive and reliable strategy to track the progression of CADASIL over time. Dr. Schoemaker is currently optimizing an enzyme-linked immunosorbent assay (ELISA) to quantify the concentration of the Notch 3 ectodomain (N3ECD) in the blood. Previous work in animal models from our research group has revealed that blood levels of N3ECD are affected in CADASIL and are related to disease severity, suggesting that this could represent a clinically useful biomarker.

Over the next period, we will continue optimizing assays for quantification of blood levels of N3ECD, as to obtain a protocol that is highly sensitive to variations in N3ECD levels, and reliable. We will also work on optimizing assays for other potentially relevant blood biomarkers for CADASIL. Finally, we aim to examine associations between levels of these biomarkers and clinical symptoms of the disease, including cerebrovascular burden on magnetic resonance imaging (MRI) and cognitive changes. These analyses would allow determining whether these biomarkers are accurately mirroring symptoms of CADASIL and could be used to estimate disease progression.

**Research Alliance
Joseph Arboleda-Velasquez MD, PhD
Schepens Eye Research Institute of Mass. Eye and Ear
Harvard Medical School

2019 grant funded by Penn Medicine Million Dollar Bike Ride Team CADASIL
$81,000

The emerging view from our recent work on CADASIL is that fundamental alterations in extracellular matrix proteins drive early functional deficits in the reactivity of the brain vasculature. In the smooth muscle cells that constitute the arterial wall, voltage-dependent potassium (Kv) channels act as a brake on contractility. We have found that a significant increase in the number of Kv channels underlies cerebrovascular dysfunction in CADASIL syndrome.

Importantly, CADASIL is caused by mutations in the NOTCH3 receptor, which is expressed not only in vascular smooth muscle cells, but also in pericytes. Pericytes are mural cells that wrap around the endothelial cells forming the capillaries. They are an under-studied cell type while increasing evidence suggests that contractile pericytes regulate capillary blood flow. Virtually nothing is known about the impact of CADASIL on pericytes and whether extracellular matrix dysregulation impairs pericyte contractility, and therefore cerebral blood flow regulation. The overall goal of this project is to provide a better understanding of the impact of the CADASIL-causing mutation on cerebral blood flow regulation by pericytes at the capillary level.

***Seed Funding

Collaboration with Penn Medicine Orphan Disease Center
Million Dollar Bike Ride funded
PI: Fabrice Dabertrand, PhD
The Dabertrand Lab
University of Colorado at Denver

2019

In the Fall 2018 funded research focused on the generation of in vivo models for testing the preclinical efficacy of our therapeutic antibody on different animal models. Our previous published work reported on the treatment of models carrying the C455R mutation in Notch 3. We are currently conducting studies in models carrying the R1031C mutation. Validation of our findings in models with different CADASIL mutations in Notch3 will demonstrate how general the results are and also the extent to which our therapeutic antibody may impact disease in the larger population of individuals with CADASIL.

**Research Alliance
Joseph Arboleda-Velasquez MD, PhD
Schepens Eye Research Institute of Mass. Eye and Ear
Harvard Medical School

Patient Data Sharing of Genetic and Health information Informs Genetics Discovery and Fuels Research

Broad sharing of genomic and phenotypic data is needed to inform variant classification, gene-disease validity assessments, and genomic medicine. The Clinical Genome Resource (ClinGen) has engaged 2340 patients in data sharing through its patient registry, GenomeConnect, since 2014. The registry is open to anyone who has had genetic testing, and, to date, has shared 969 sequence variants with ClinVar. These efforts have resulted in 491 (51%) previously unsubmitted sequence variants being added to ClinVar, additional case-level evidence being made available, 25 variant classification updates being identified and shared, and numerous requests for additional information from clinicians and researchers. Given GenomeConnect’s success in patient data sharing, we sought to broaden efforts by working with external registries that may be collecting data but not sharing publicly. We initiated a pilot to engage patient registries in data sharing and assess the utility of data shared from these groups. Here, we report on a pilot of 100 individuals from five external registries in the Patient-Data Sharing Program.

View larger graphic here.

 

Authors and Affiliations:

Juliann M. Savatt1, Danielle R. Azzariti2, W. Andrew Faucett1, Jon Florin3, David H. Ledbetter1, Vanessa Rangel Miller3, Emily Palen1, Heidi L. Rehm2,5,6  Jud Rhode3, Les Rogers7, Sandra Talbird8, Laura Trutoiu9, Jo Anne Vidal3, Christine Waggoner10, Erin Rooney Riggs1, Christa Lese Martin1

1Geisinger, Danville, Pennsylvania; 2The Broad Institute of MIT and Harvard, Cambridge, Massachusetts; 3No Stomach For Cancer, Middleton, Wisconsin, 4Invitae, San Francisco, California; 5Center for Genomic Medicine, Massachusetts General Hospital, Boston, Massachusetts; 6Harvard Medical School, Boston, Massachusetts, 7CFC International, St. Petersburg, Florida, 8CureCADASIL, Plainsboro, New Jersey, 9Association for Creatine Deficiencies, Carlsbad, California,  10Cure GM1 Foundation, Albany, California

From July 2018 and May 2019, five organizations began engaging participants in data sharing – Association for Creatine Deficiencies, Cardio-Facio-Cutaneous Syndrome International, CureCADASIL, No Stomach For Cancerand GM1 Patient Network. Registry participants control their participation via an online consent within their registries. Those who opt to share data  are asked to upload a copy of their genetic testing report to their account to allow for uniform data mining, may be invited to complete additional surveys to collect additional phenotype data, and are provided with the option to receive updates regarding their results. Fifty-six percent of participants uploaded their report. Genetic counselors review reports to ensure standardized data collection and submitted de-identified data to ClinVar. A total of 81 unique variants were shared, of which 45.6% (n=37/81) were novel to ClinVar demonstrating that condition specific registries are a source of novel variants. Participants also provided additional health and case-level information that could inform future gene and variant curation efforts, such as those performed by ClinGen. Of variants that were previously submitted by the reporting laboratory, 12% (n=3/25) were out of date compared to the current classification. These pilot data show that registries can empower patients to contribute valuable information to the public knowledge base, benefiting patients and the genetics community.

2018

Suning Ping, a post-doctoral fellow in Dr. Li-Ru Zhao’s lab at SUNY Upstate Medical University in Syracuse, received a student travel grant from cureCADASIL to present her work entitled “STEM CELL FACTOR AND GRANULOCYTE COLONY-STIMULATING FACTOR PROMOTE BRAIN REPAIR AND COGNITIVE FUNCTION THROUGH VEGF-MEDIATED ANGIOGENESIS IN A MOUSE MODEL OF CADASIL”. Dr. Li-Ru Zhao’s lab has recently demonstrated the efficacy of combining two hematopoietic growth factors. Stem cell factor (SCF) and granulocyte colony-stimulating factor (G-CSF) improve cognitive function, increase brain blood vessel density and increase neural network rewiring in a transgenic mouse model of CADASIL. Dr. Ping demonstrated that a third growth factor, vascular epithelial growth factor (VEGF), is necessary for SCF and G-CSF to function. By blocking VEGF with Avastin, the improvement in cognitive function, enhanced blood vessel density and enhanced neural network rewiring that was observed with SCF and G-CSF does not occur. Dr. Ping’s results shed light on a key mechanism by which hematopoietic growth factors may restrict CADASIL pathology. Read the Abstract.

**Young CADASIL Investigators
PI: Li-Ru Zhao MD, PhD
Postdoc: Ping Suning
Lab of Dr. Li-Ru Zhao
SUNY Upstate Medical University in Syracuse

The purpose of this summer fellowship funded by cureCADASIL was to understand the dysregulation of NOTCH signaling in CADASIL through immunohistological characterization of brain vasculature from CADASIL subjects and controls. Given the diversity in CADASIL-causing NOTCH3 mutations, our approach was to use a diverse cohort of NOTCH3 mutations to address the hypothesis that CADASIL is a disease caused by loss of function in NOTCH signaling. Utilizing a combination of markers for distinct vascular cell types, classical and novel NOTCH3 signaling targets we characterized the cellular consequences of CADASIL causing NOTCH3 mutations on brain vasculature. This fellowship aided to further advance our understanding of the consequences of NOTCH3 dysregulation in brain vasculature of CADASIL patients and provide preliminary data to support a grant submission to continue this work.

***Seed Funding
PI: Luisa Iruela Arispe MSc, PhD
Postdoc: Milagros Romay, PhD
Student: Margaret Ramirez
The Arispe Lab
University of California at Los Angeles

Funding to initiate experiments with animals carrying the R1031C mutation. This analysis is critical for us to examine how many patients could potentially benefit from our modality of treatment: only those with a specific mutation or patients with different mutations associated to different mechanisms.

**Research Alliance
Joseph Arboleda-Velasquez MD, PhD
Schepens Eye Research Institute of Mass. Eye and Ear
Harvard Medical School

Dr. Dorothee Schoemaker is a Post-Doctoral fellow in the lab of Dr. Joseph Arboleda- Velasquez.  She will work with cureCADASIL to grow and enrich the registry of CADASIL subjects and will work with members of the medical and research community to increase our understanding of the vascular contributions to cognitive decline.

**Research Alliance
Joseph Arboleda-Velasquez MD, PhD
Schepens Eye Research Institute of Mass. Eye and Ear
Harvard Medical School

2017

Funds provided by cureCADASIL have been instrumental in addressing additional experiments suggested by reviewers from the journal considering publication of our in vivo testing of a potential treatment for CADASIL. Specifically, we were able to conduct additional analyses of brain integrity to evaluate vascular leakage and how it can be prevented. We were also able to fund additional experiments to enable another animal trial. Funds were used to generate more animal model mice, determine whether or not they carry the CADASIL mutation and support their maintenance. The latter will include animals with established brain pathology to determine the potential effect of the drug. This will be informative of potential efficacy in patients with moderate to advanced CADASIL.

**Research Alliance
Joseph Arboleda-Velasquez MD, PhD
Schepens Eye Research Institute of Mass. Eye and Ear
Harvard Medical School

2016

Supplemental funding assisted in identifying a roster of blood biomarkers that have the potential to report whether a therapy for CADASIL would be effective in clinical trials. These biomarkers include proteins that are significantly more or less abundant in the presence of CADASIL and revert to their normal levels after treatment with an experimental drug in laboratory models. We are launching a major effort to further develop and validate these biomarkers in blood from CADASIL patients as a necessary step towards the goal of launching a clinical trial that will test the safety and efficacy of experimental treatments for CADASIL. As part of the plan we will 1) develop assays specific for the human proteins, 2) analyze samples already collected from research sites from around the world, and 3) establish the foundation for collection of additional samples in the US. Validation of these biomarkers will enable the design of clinical studies to evaluate modalities of treatment that Dr. Arboleda-Velasquez found to be promising in laboratory models of CADASIL.

**Research Alliance
Joseph Arboleda-Velasquez MD, PhD
Schepens Eye Research Institute of Mass. Eye and Ear
Harvard Medical School

The aim of this summer internship funded by cureCADASIL was to image and quantify these defects extensively and begin describing the mechanism involved. Determine if notch functions cell autonomously in mechanosensory neurons. Begin investigating the mechanism of action of Notch in mechanosensory neuron connectivity and address the potential link to CADASIL.  This research is described in a publication presented in a poster at the 2017 Society for Neuroscience. Quin Brown Poster Summer Research 2k16 (3)

**Young CADASIL Investigators
PI: Rachid El Bejjani, PhD
Student: Quin Brown
Davidson College