Daniel Shah
BME PhD Proposal Presentation

Date: 2025-10-29
Time: 2:00 PM - 4:00 PM
Location / Meeting Link: EBB CHOA Seminar Room / https://gatech.zoom.us/j/99447617867?pwd=N7ig6YuyzWpf79ZObfwdKS3PM5TY1F.1 Passcode: 706638

Committee Members:
Edward A. Botchwey, Ph.D. (advisor); Andrés J. García, Ph.D.; Steven L. Goudy, M.D.; Karmella A. Haynes, Ph.D.; Steven L. Stice, Ph.D. 


Title: Engineering Mesenchymal Stromal Cell-Derived Extracellular Vesicles via Lipid Remodeling for Enhanced Regenerative Therapies

Abstract:
Cleft palate repair is one of the most common reconstructive surgeries performed in infants, yet failure rates remain high, with up to 60% of procedures complicated by the development of oronasal fistulas (ONF). These chronic, non-healing defects impair speech, feeding, and quality of life, requiring repeat surgical interventions throughout adolescence. The persistence of ONF highlights a critical gap in our understanding of intraoral wound healing and underscores the need for regenerative therapies that address the underlying immune dysregulation and impaired tissue remodeling at the mucosal interface. Mesenchymal stromal cells (MSCs) and their extracellular vesicles (EVs) have shown immense promise as immunomodulatory and pro-regenerative therapeutics. However, difficulty scaling EV production and the therapeutic consistency of MSC-derived EVs remains limited by heterogeneity in vesicle cargo composition and bioactivity. This proposal aims to enhance EV potency and cargo loading through metabolic engineering. Aim 1 investigates how sphingomyelinase (SMase) licensing of MSCs alters lipid metabolism to influence EV formation, cargo trafficking, and therapeutic activity. We will characterize MSC health and function following SMase treatment, define changes in EV biogenesis and immunomodulatory potency, and evaluate the regenerative effects of SMase-engineered EVs in a murine ONF model. Aim 2 will define immunoregulatory mechanism of SMase‑licensed EVs via their endogenously packaged miRNA and protein cargo, and in parallel evaluate EVs exogenously loaded with selected cargo to strengthen potency. We will quantify cargo composition, loading efficiency, uptake, and routing in both human and murine mononuclear cell populations. Assessment of functional cellular reprogramming through cytokine profiling and spectral flow cytometry will be conducted. Additionally, endogenous and loaded EV formulations will be implanted in a murine ONF model with tissue remodeling, immune cell phenotyping, and vascular development endpoints. By integrating lipid-primed EV formation with targeted cargo delivery, this project will develop a new paradigm for tunable, cell-free regenerative therapeutics in oral mucosal repair.