blood CD4 cell count blood CD45RC CD4 T cell count 2014-04-25T11:29:00Z CMO:0002346 JSmith Measurement of the number of lymphocytes in a specified sample of blood which express both the surface CD45RC antigen and surface CD4 antigen. D45RC, also known as the leukocyte common antigen, is the protein produced by the PTPRC (protein tyrosine phosphatase, receptor type, C) gene and has been shown to be an essential regulator of T- and B-cell antigen receptor signaling. blood CD45RC(+) CD4(+) T cell count blood CD45RC+ CD4+ T cell count blood LCA T4 T cell count clinical_measurement_ontology