Macardle, P.Chen, Z.Shih, C.Huang, C.Weedon, H.Sun, Q.Lopez, A.Zola, H.2006-06-232006-06-231996Cellular Immunology, 1996; 168(1):59-680008-87491090-2163http://hdl.handle.net/2440/7107Human leucocytes from peripheral blood and tonsil were examined for the presence of the IL-3 receptor using monoclonal antibodies directed to epitopes of the alpha and beta chains of the receptor. We found that the beta chain, common to IL-3, IL-5, and GM-CSF, was either present at low levels or not detected on the majority of peripheral blood and tonsil B lymphocytes, while the alpha chain showed a distinct but restricted distribution. In peripheral blood the IL-3R alpha chain was limited to a subpopulation of peripheral B lymphocytes and a population of cells which lack lineage-specific markers. Dimly staining cells were identified as B lymphocytes as they coexpressed CD19, CD20, CD22, CD24, and HLA-DR. A brightly staining population lacks T and B lymphocyte, NK specific, and macrophage lineage markers but expresses CD9, CD45RO, CD26, and, in a proportion of cells, CD36 and CD60. This population remains unclassified. In tonsil tissue IL-3R alpha chain expression was strongest on B lymphocytes present in the T cell rich areas of tonsillar tissue. The IL-3R alpha bearing B tonsil cells included cells in both CD23 and IgD positive and negative populations. The phenotype of the IL-3R alpha positive B cells defines them as a population of B lymphocytes distinct from previously characterized cells in the lymphoid architecture. Lymphoblastoid cell lines with a corresponding phenotype were also identified.enB-LymphocytesLeukocytes, MononuclearCell LineHumansReceptors, Interleukin-3Antigens, CDCell SeparationLymphocyte ActivationChildChild, PreschoolPalatine TonsilJournal article0030005701001996447810.1006/cimm.1996.0049A1996TY854000072-s2.0-002998969469707Lopez, A. [0000-0001-7430-0135]