Characterization of surface receptors on bovine leukocytes.
Three bovine leukocyte populations--peripheral blood lymphocytes (PBL), mammary gland polymorphonuclear neutrophils (PMN) and macrophages (Mo)--were characterized with respect to five surface markers: surface immunoglobulin (SIg), sheep erythrocyte receptor, complement (C) receptor and Fc receptors for both IgG and IgM. The majority of PMN and Mo possessed C and Fc receptors for IgG, but lacked SIg and the erythrocyte receptor. The PMN, but not Mo, also expressed a Fc receptor for IgM. The PBL were heterogeneous with respect to their surface characteristics and evidence was presented for the following subtypes: (a) cells with the E receptor alone; (b) cells with E receptor plus the Fc(IgG) receptor; (c) cells with SIg plus the C receptor but minus the Fc(IgG) receptor; (d) lymphocytes with SIg plus the C receptor and the Fc(IgG) receptor, and (e) cells lacking E receptors and SIg but bearing Fc(IgG). It was assumed, but not proven, that some of these latter cells must also bear the C receptor. The significance of the various cell types in antiviral defense is briefly discussed.
D000818:Animals; D001665:Binding Sites; D001666:Binding Sites, Antibody; D002417:Cattle; D002469:Cell Separation; D003165:Complement System Proteins; D007141:Immunoglobulin Fc Fragments; D007074:Immunoglobulin G; D007075:Immunoglobulin M; D007962:Leukocytes / Q000276:immunology*; D011947:Receptors, Antigen, B-Cell; D012397:Rosette Formation
D007141:Immunoglobulin Fc Fragments; D007074:Immunoglobulin G; D007075:Immunoglobulin M; D011947:Receptors, Antigen, B-Cell; D003165:Complement System Proteins