Robert J. Hayashi, M.D.

DEPARTMENT OF Pediatrics
Keywords: bone marrow transplant, graft vs. host disease, T lymphocytes

Dr. Hayashi's research interests primarily focus on issues regarding immune regulation, particularly in the area of regulation of lymphocyte activation. His laboratory research interests thus focus on mechanisms of T lymphocyte tolerance and how the immune system is made unresponsive to a variety of stimuli. In vitro and in vivo models are utilized to characterize the exact molecular mechanisms that regulate pathways involved in T cell activation, tolerance and deletion. This will enhance our understanding of how the immune system is regulated and also how this regulation is disrupted in conditions such as graft vs. host disease, post-transplant lymphoproliferative disease (PTLD), and the development of lymphoma.

Dr. Hayashi's clinical interests focus on bone marrow transplantation, particularly in the realm of graft vs. host disease and PTLD. The Bone Marrow Transplant Program at St. Louis Children's Hospital emphasizes the use of allogeneic transplant in the treatment of a variety of malignant and non-malignant diseases. Protocols using a variety of donors including matched, unrelated bone marrow and umbilical cord blood are currently being used with the hope of maximizing the efficacy of bone marrow transplant and minimizing its toxicity. Studies in the area of PTLD include elucidating mechanisms in the pathogenesis of the disease and the development of therapeutic protocols to facilitate its treatment.