Effects of Mechanical Stress and Phenotype Switching on Human Stem Cell-Derived Vascular Smooth Muscle Cells: Modeling Gene Regulatory Networks

Johns Hopkins University, Baltimore MD

Investigators

Abstract

This project will reveal how human vascular smooth muscle cells (vSMCs) adapt to mechanical forces like blood pressure to switch from a state that favors the formation of new vessels to one designed to control blood flow to tissues. The mechanisms responsible for this transition in humans are poorly understood, despite the importance of this switch in human vascular development and tissue repair. Beyond scientific advances, the project will promote the training and education of undergraduate and graduate students in cell biology, physics and computational modeling that will prepare them for careers in academia and industry. Research internships with a local majority-minority magnet math-science high school will also offer training opportunities for Baltimore City students to encourage STEM-based careers. Long-term the benefits to society will likely include new approaches to model or utilize vSMCs for vessel formation and vascular repair. The goal of this research is to determine how mechanical forces regulate vSMC phenotype switching using a human vSMC surrogate model of perinatal development. The model system employed here relies on lineage-specific vSMCs differentiated from human induced pluripotent stem cells with well-defined synthetic and contractile phenotypic states. The mechanical properties and response of these vSMCs to stress/strain will be assessed using platforms that enable single cell analyses and stretching of cells in both 2D and 3D geometries. Once “tuned” to maximize internal force development, the model systems will be used with RNA-seq, bioinformatics, and computational modeling to identify key regulatory factors (e.g., transcription factors, signaling molecules) and to model regulatory networks predicted to control hPSC-vSMC responses to increased stress/strain. When coupled with ChIP-seq assays, the results will be used to decipher how mechanical forces affect transcriptional mechanisms responsible for phenotype transitions in vSMCs. This project is funded jointly by the Cellular Dynamics and Function (CDF) and Systems and Synthetic Biology (SSB) clusters of the Division of Molecular and Cellular Biosciences. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.