title: Binding of phosphorylcholine by non-immunoglobulin molecules on mouse B cells.
abstract: Phosphorylcholine (PC), a molecule found in the cell wall of most serotypes of pneumococcus, has been used extensively as a probe for the study of network interactions during immune responses. The frequency of B lymphocytes capable of interacting with PC has not been directly examined. We used immunofluorescence to study the binding of PC and monoclonal anti-TEPC15 anti-idiotopic antibodies to murine lymphocytes. In addition to identifying PC-specific Ig molecules, PC was bound by a non-Ig molecule on the surface of a relatively large subset of B cells; this non-Ig marker shared an idiotypic determinant with the PC-binding myeloma protein HOPC8 (H8). PC-bearing R36a pneumococci bind to a similar subset of lymphocytes. This binding is inhibited specifically by PC coupled to bovine serum albumin and also by a monoclonal anti-H8 antibody. We suggest that bacterial interaction with B cells through non-Ig molecules capable of binding a dominant antigen like PC may possess functional significance, possibly during the events that lead to antibody induction by these microorganisms.
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology; D000942:Antigens, Bacterial; D001665:Binding Sites; D001854:Bone Marrow Cells; D002794:Choline / Q000031:analogs & derivatives*; D051379:Mice; D008805:Mice, Inbred A; D008807:Mice, Inbred BALB C; D008814:Mice, Inbred NZB; D008817:Mice, Mutant Strains; D010767:Phosphorylcholine / Q000276:immunology / Q000378:metabolism*; D011947:Receptors, Antigen, B-Cell / Q000032:analysis*; D012710:Serum Albumin, Bovine / Q000378:metabolism; D013154:Spleen / Q000166:cytology; D013296:Streptococcus pneumoniae / Q000378:metabolism
chemical_list: D000911:Antibodies, Monoclonal; D000942:Antigens, Bacterial; D011947:Receptors, Antigen, B-Cell; D010767:Phosphorylcholine; D012710:Serum Albumin, Bovine; D002794:Choline