Abstract
Mesenchymal stromal cell (MSC)-derived extracellular vesicles (EVs) offer a cell-free strategy for tissue repair, but variability in cargo, delivery, and recipient-cell responses can limit therapeutic precision. Our research uses skin regeneration as a model to move from native MSC-EVs toward mechanism-guided engineered EV therapeutics. In previous work, human umbilical cord MSC-derived exosomes promoted murine wound healing and reshaped neutrophil and macrophage states at single-cell resolution, supporting immune reprogramming as an important regenerative mechanism. Building on these findings, our current research is extending EV-based therapy toward engineered platforms designed to improve control of regenerative cargo, tissue delivery, and cell-state-selective responses in skin and hair disorders. Single-cell transcriptomics is used to map recipient cell states and identify pathways most responsive to EV intervention, while scQCenrich provides multi-metric quality control to reduce technical bias and preserve biologically informative cells. In parallel, our photoaging studies demonstrate that disease-associated dermal remodeling can be therapeutically redirected in defined fibroblast states, providing a mechanistic framework for selecting regenerative targets and evaluating engineered EV activity. Together, these studies support a precision-EV paradigm in which single-cell-defined mechanisms guide EV engineering, and therapeutic efficacy is assessed by the capacity to reprogram pathological cell states in addition to restoring tissue structure. This framework may accelerate development of reproducible, mechanism-based engineered EV therapies for wound repair, photoaging, and hair regeneration.
Biography
Yuanyuan Liu, MD, PhD, is a dermatologist and physician-scientist at Peking University People’s Hospital. She completed her PhD in Dermatology and Venereology at the PLA General Hospital Graduate School and postdoctoral research at Northwestern University Feinberg School of Medicine. Her research focuses on mesenchymal stromal cell-derived and engineered extracellular vesicles for skin and hair regeneration, together with single-cell and multi-omics approaches for defining therapeutic mechanisms. Her recent work includes extracellular-vesicle-mediated wound repair, single-cell analysis of photoaged skin, and development of scQCenrich for single-cell RNA-sequencing quality control.
