thymocyte count CD45R+ thymocyte count 2013-10-23T13:04:48Z CD45R+ thymic lymphocyte count CD45R-positive thymocyte count CMO:0001846 PTPRC+ thymocyte count The number of lymphocytes expressing the CD45 receptor (protein tyrosine phosphatase, receptor type, C; PTPRC) on their surface in a specified sample of thymus tissue. PTPRC is a transmembrane protein specifically expressed in hematopoietic cells which has been shown to be an essential regulator of T- and B-cell antigen receptor signaling. The thymus is the lymphoid organ which is the site of the proliferation, differentiation and maturation of T lymphocytes, and of the production of hormones such as thymopoietin and thymosin which control these processes. clinical_measurement_ontology jsmith leukocyte common antigen (LCA) positive thymocyte count