Defining the role of NLRP3 inflammasome in clonal hematopoiesis

PROJECT SUMMARY This NIH K08 Career Development Award proposal describes a five-year training program studying the role of NLRP3 inflammasome in Tet2-/- clonal hematopoiesis. The widespread presence of blood cells harboring somatic genetic alterations in the absence of any hematologic malignancy defines the condition known as clonal hematopoiesis of indeterminate potential (CHIP). Both human and mouse studies have demonstrated significant associations between CHIP and cardiovascular disease, chronic obstructive pulmonary disease, chronic liver disease, osteoporosis, and gout. Focused studies on the genes most frequently mutated in CHIP, epigenetic regulators TET2 and DNMT3A, have implicated increased chemokine expression and inflammasome hyperactivation in myeloid cells as a possible mechanistic connection between CH and these diseases. Dysregulated innate immune and inflammatory signaling also contribute to preleukemic states and pathogenesis of myeloid disease, but precise mechanisms remain unclear. I propose in Aim 1 to study the role of NLRP3 inflammasome, a key regulator of inflammation and innate immunity, in mediating Tet2-/- clonal hematopoiesis. I will characterize the functional role of NLRP3 using an orthogonal approach of clonal hematopoiesis mouse models, human xenografts and patient specimens. In Aim 2, I propose to characterize the function of NLRP3 inflammasome at the transcriptional and chromatin levels using single cell sequencing technology. I will further define the hematopoietic progenitor compartment responsible for Tet2-deficient, NLRP3-dependent clonal expansion. This work will implicate NLRP3 inflammasome activity in the development of clonal hematopoiesis and suggest new strategies to target the inflammatory drive in CHIP. The applicant, Dr. Waihay Wong, has completed clinical training in Anatomic Pathology and Hematopathology at Brigham and Women’s Hospital (BWH) and Harvard Medical School (HMS). He will complete a research program focused on training as an independent investigator to study the role of NLRP3 inflammasome in mediating Tet2-/- clonal hematopoiesis. Dr. Wong proposes to develop expertise in next-generation sequencing, computational analysis, and mouse models of disease. The mentor, Dr. Benjamin Ebert (HHMI Investigator, Professor of Medicine at HMS and Chair of Medical Oncology at Dana-Farber Cancer Institute, DFCI), is a renowned expert in the biology of hematopoietic cells and clonal hematopoiesis. Dr. Ebert has successfully mentored numerous physician-scientists to become independent academic investigators. This mentoring will be supported by formal course work, seminars, presentations at international meetings, and regular meetings with Dr. Wong’s Advisory Committee which has complementary expertise and experience in mentoring physician-scientists to develop independent research programs. Dr. Wong will conduct this research at the DFCI and leverage the exceptional research and teaching environment at the DFCI, Harvard, and the Broad Institute to complete this work and realize his long-term career goal of becoming an independent physician-scientist.