Ke Xu

Team leader of Exosome Engineering and Exploratory Research, with responsibilities across Discovery, Pre-Clinical R&D, Translation, and IND enabling studies. • Exosome Engineering Leading the development and initial implementation of the engEx™ platform, including characterization and application of multiple novel exosomal markers. • Molecular and Cellular Biology Overseeing the Molecular Cellular Biology functions to organize the company-wide libraries/storages for expression constructs and engineered cell lines. • Genome Editing Overseeing the Gain-of-Function and Loss-of-Function Genome editing group (Meganucleases/CRISPR/Cas9) • Discovery Research Leading and coordinating research groups focusing on Exosome Biology, Tissue Tropism, Targeted Delivery, Gene therapy, Stem Cells (HESC/iPSC), immuno-oncology and vaccines. • Assay Development, target discovery and validation • Pre-IND studies and IND support

CRISPR/Cas9 and TALEN mediated genome editing in neurodegenerative disease models. • Established human embryonic stem cell reporters (HB9 induced fluorescent lines) facilitating neural degenerative disease research using TALEN/CRISPR technology. • Generated engineered iPSCs diseases models for neuro-degenerateive disease drug discovery.

Stem Cell Biology and Diabetes Mentor: Douglas A. Melton • human embryonic stem cells (hESC) and induced pluripotent stem cells (iPSCs) • directed stem cell differentiation aiming for making functional pancreatic beta cells for treating Diabetes • islet biology and diabetes disease models • Genome Editing (CRISPR/Cas9, TALEN)

Sonic Hedge Hog regulatory network Mentor: Andrew P. McMahon • neural patterning • long noncloding RNAs (lncRNA/lincRNA)

Department of Molecular Biology • Molecular profiling of genes regulating blood vessel development (vasculogenesis and angiogenesis)

Department of Cell Biology • Imaging and Photocaged fluorescent probes development • Gap-junctional cell communication

DISSERTATION: RASIP1 REGULATES VASCULAR TUBULOGENESIS Mentor: Ondine Cleaver Thesis Committee: Thomas Carroll, Melanie Cobb, Eric Olson Cardiovascular function depends on patent blood vessel formation by endothelial cells (ECs). This study identifies Rasip1 as a unique, endothelial-specific regulator of Rho GTPase signaling, which is essential for endothelial lumen morphogenesis. We found that Rasip1 is strongly expressed in vascular endothelial cells throughout development across species. Ablation of Rasip1 both in vitro and in vivo strongly affects vascular integrity. Mice lacking Rasip1 fail to form patent lumens in all blood vessels, including the early endocardial tube. The defects from Rasip1 deletion result from increased RhoA/ROCK/myosin II activity and blockade of Cdc42 and Rac1 signaling. Together, our work identify Rasip1 as a novel endothelial factor that plays an essential role in vascular tubulogenesis.