Pratibha Singh, PhD
Assistant Research Professor of Microbiology & Immunology
My research focuses on understanding mechanisms that regulate normal and stressed hematopoietic stem and progenitor proliferation, differentiation and survival, and the role played by bone marrow niche support cells in hematopoietic stem cell function.
Current clinical hematopoietic transplant (HCT) relies on moving HSPC from bone marrow (BM) to the circulation, a process called peripheral blood stem cell mobilization (PBSCM), with G-CSF (Neupogen) being the primary drug used clinically for PBSCM. However, little is known about the mechanisms governing HSPC egress. Understanding this process has major relevance for clinical HCT. Poor homing and inadequate expansion, survival and differentiation of transplanted HSPC can limit transplant efficacy. Understansing hematopoietic stem cell regulation will allow us to develop improved stratiegies for hematopoietic stem cell based therapies, and facilitate recovery of hematopoieisis following stress and injury such as chemo/radio therapy or acute radiation exposure. My research interests include identifying mechanisms of action of Neuropeptide Y on hematopoietic cells and on the function of stromal niche support cells and in regulation of hematopoietic stem and progenitor cells trafficking. I am currently exploring the role of sinusoidal endothelial cells in hematopoietic stem cell maintenance and trafficking and have identified an unappreciated role for DPP IV- Neuropeptide Y axis in regulation of endothelial cell barrier permeability and hematopoietic stem cell trafficking. I am also investigating the role of Survivin in regulating mesenchymal stem cell functions and I have identified a previously unknown role for Survivin in the mesenchymal stem cell survival/proliferation and maintenance of hematopoietic stem cell niche. My emerging interest is to investigate the role of stromal cell populations in regulation of hematopoiesis following stress, particularly in niche regeneration after myeloablative injury such as radiation exposure.