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Katherine A. Hajjar, M.D.

Brine Family Professor of Cell & Development Biology
Professor and Vice Chair for Reseach
Department of Pediatrics
Associate Dean for Faculty Development


Dr. Katherine Hajjar is physician-scientist, Professor of Pediatrics, Professor of Medicine, and the Brine Family Professor of Cell and Developmental Biology at the Weill Cornell Medical College.  She received her undergraduate degree from Smith College, and her MD degree from the Johns Hopkins University School of Medicine.  She completed clinical training in Pediatrics at Children’s Hospital of Pittsburgh, where she also served as Chief Pediatric Resident, and completed a fellowship in Pediatric Hematology-Oncology at Johns Hopkins University School of Medicine.  She has been a member of the faculty at Weill Cornell since 1984.


Dr. Hajjar’s lab studies the biologic roles of the annexins, a family of calcium-sensing, membrane-binding proteins.  Her lab identified the major endothelial cell fibrinolytic receptor as the annexin A2 complex, and defined its binding interactions with plasminogen and its activator tissue plasminogen activator.  She created the annexin A2 deficient mouse and related knockouts, and demonstrated that A2 is critical for normal hemostasis in mice and humans. Dr. Hajjar also defined the role of annexin A2 in pathologic angiogenesis, and, based on these findings, her group is now developing a first-in-class therapeutic agent for retinopathy of prematurity and diabetic retinopathy.  Other projects in her lab explore the role of the annexin A2 system in the regulation of vascular permeability and innate immunity.


Dr. Hajjar is a member of the American Society for Clinical Investigation, the Association of American Physicians, and the American Clinical and Climatological Association.  She is also a fellow of the American Association for the Advancement of Science, and Member-at-Large of its Section on Medical Sciences.  She is the recipient of an Established Investigator Award from the American Heart Association (AHA), a Syntex Scholar Award, the AHA’s Irvine Page Award, and the Key to Life Award from the Children’s Blood Foundation. She has served as president of the New York Society for the Study of Blood, the Interurban Clinical Club, and the Harvey Society.  She has organized numerous international meetings and workshops, and served on multiple review panels and editorial boards. 



Weill Cornell Medicine
Gale and Ira Drukier Institute for Children's Health
413 E. 69th Street New York, NY 10021