Joyce Bischoff received an A.B. in chemistry from Duke University and a Ph.D. in biochemistry from the Washington University School of Medicine. She was a post-doctoral fellow at the Whitehead Institute for Biomedical Research. She joined the Surgical Research Laboratories, now called the Vascular Biology Program, at Children's Hospital in 1990. She was promoted to Professor in the Department of Surgery at Harvard Medical School in 2010.
Instructor
Sana Nasim received her BS in Biomedical Engineering and a minor in Applied Mathematics from New Jersey Institute of Technology and a PhD in Biomedical Engineering from Florida International University in 2020. She joined Dr. Bischoff’s laboratory as a postdoctoral fellow where she focuses on capillary malformations caused by the GNAQ R183Q mutation in endothelial cells and how this impacts endothelial barrier formation, response to flow, and interaction with surrounding mural cells and immune cells. Sana was promoted to Instructor at HMS in January 2025.
Research Fellow
Annegret Holm is a Physician Scientist and Instructor at Harvard Medical School dedicated to improving outcomes for patients with vascular anomalies through translational research and clinical care.
In Joyce Bischoff's lab, she led the discovery of the endothelial SOX18-mevalonate pathway axis as a mechanistic driver in vascular anomalies. Her current research focuses on further characterizing this pathway and its precise molecular targeting. She has initiated the clinical translation of these findings through multicenter collaborations with vascular anomalies centers in the U.S. and Europe.
She holds an MD from Heidelberg University, in Heidelberg, Germany; completed clinical training in Pediatrics and Pediatric Hematology/Oncology at the University Hospital in Freiburg, Germany; and conducted doctoral research in vascular biology under Hellmut Augustin at the German Cancer Research Center in Heidelberg.
Annegret serves as Deputy Lead for Germany in VASCERN, the European Reference Network for Vascular Anomalies. She is a member of the Research Foundations project of the US vascular anomalies network (VAN), and a contributing editor of the vascular biology publication alert of the North American Vascular Biology Organization (NAVBO).
Postdoctoral Research Fellow
Mehrnaz Mehrabipour received her BSc and MSc degrees in Cellular and Molecular Biology from Shahid Bahonar University of Kerman, Iran. She received her PhD in Biochemistry and Molecular Biology from Heinrich Heine University in Düsseldorf, Germany, supported by a fellowship from the German Research Foundation (DFG). Her thesis focused on the SH3 protein domains, biophysical and biochemical analysis of protein-protein and protein-lipid interactions within signaling pathways, and the identification of SIRT4 and C-RAF kinase regulatory functions within the RAS/MAPK pathway. She also worked on the functional impact of RAS pathway variants associated with arteriovenous malformations (AVMs), integrating biochemical, structural, and translational approaches to study how signaling alterations contribute to vascular disease.
In Joyce Bischoff’s lab, Mehrnaz studies the molecular and epigenetic mechanisms underlying vascular tumors, with a particular focus on infantile hemangioma (IH). Her research explores RAS/MAPK pathway regulation, retrotransposons, and genome regulatory programs in vascular disease. Her work combines patient-derived models, functional genomics, biochemical approaches, and translational strategies to better understand mechanisms driving aberrant vasculogenesis and strategies for precise molecular targeting to prevent vascular tumors and vascular malformations.
Research Technologist I
Jill obtained her Master of Science in Plant Molecular Biology from University of Michigan and her Master of Arts in Professional Writing with a concentration in Biomedical Sciences from Western Michigan University in 1998. In 2001, Jill joined the Bischoff Lab as a Research Technician with graduation to Research Technologist I.