Modulating the Stem Cell Secretome for the Treatment of Ehlers-Danlos Syndrome
Abstract
Fiscal Year 2022 (FY22) Peer Reviewed Medical Research Program (PRMRP) Portfolio Category: Internal Medicine. FY22 PRMRP Topic Area: Ehlers-Danlos Syndrome. FY22 PRMRP Strategic Goal: Treatment: Develop and test novel treatments, and/or improve upon existing treatments for associated diseases and conditions. Ehlers-Danlos syndrome (EDS) is a heterogeneous group of genetic skin and connective tissue disorders characterized by hyperextensible skin, joint hypermobility, cutaneous fragility, delayed wound healing, and chronic pain. The disease is caused by defective proteins that participate in the assembly of extracellular matrix (ECM), a mix of molecules and minerals that form a matrix between cells. There are no treatment options for EDS patients except for symptomatic care and pain management. Because of overlapping symptoms and a poorly defined genetic basis, diagnosing EDS remains a challenge, and many patients are left undiagnosed, including military personnel. In this application, we propose to develop a so-called protein replacement therapy for EDS by replacing defective proteins in ECM with normal variants. This can be achieved by using small membrane vesicles called exosomes that are released by adult stem cells, such as mesenchymal stem/stromal cells (MSCs). MSCs are already being tested in clinical and preclinical studies for many conditions such as stroke, limb ischemia, and diabetic wounds, and their therapeutic potency is being attributed to the release of exosomes filled with a variety of factors, including proteins and messenger RNAs (mRNAs) that encode these proteins. These exosomes can release factors into the extracellular space and/or transport mRNAs into neighboring diseased cells, providing a template to produce functional proteins by these cells. However, using exosomes isolated straight from healthy MSCs may not be the most effective way to treat diseases since exosomes will only contain the factors that are naturally produced by MSCs. We hypothesized that the therapeutic potency and consistency of MSC-derived exosomes can be enhanced by tailoring the factors that are secreted by MSCs to a disease of interest. For EDS, tailoring the production and secretion of proteins that are affected by the disease is not a trivial task due to the large size of these molecules. For this reason, we developed a novel technology that allows us to increase the production of proteins that are commonly affected by EDS in healthy MSCs without any permanent genetic modifications. For that, we use a modified version of the gene editing protein Cas9, which, instead of modifying the genome of the cells, induces the activation of genes in a specific manner. The activation of EDS-specific genes in MSCs using our system should enrich the content of MSC-derived exosomes with target proteins and mRNAs encoding these proteins. The delivery of these modified exosomes into EDS affected tissues will promote the release of functional ECM proteins into extracellular space and/or production of functional versions of affected proteins by neighboring cells from provided mRNA templates. Using our humanized model of EDS that we generated previously, we will validate if exosomes isolated from MSCs with enhanced production of functional copies of EDS-associated proteins can improve the EDS characteristics observed in our mouse model. If successful in our small-scale study, the strategy will need to be validated in a large-scale study outside the scope of this proposal. While the current study will only assess the effect of a local delivery of our exosomes on EDS skin phenotype, the study can potentially be expanded to systemic delivery. EDS affects connective tissues and delays wound healing. Therefore, the exosomes that are effective in treating EDS are likely to be effective for treating other connective tissues disease, such as osteoarthritis, and for healing acute and chronic wounds, which affect both military personnel and c
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Jan 04, 2024
- Source ID
- HT94252310019
Entities
People
- Ganna Bilousova
Organizations
- United States Army
- University of Colorado Denver