Immunoglobulins on the Surface of Hamster Lymphocytes
Cell surface immunoglobulin (Ig) is important as an antigen specific receptor on B lymphocytes. It is distributed in a clonotypic fashion and may also function in the antigen-dependent triggering of B lymphocytes. In most species, the predominant isotypes of cell surface Ig are 7–8S membrane IgM (mIgM) and IgD (mIgD). Evidence from experiments with mouse lymphoid cells indicates that the class of Ig present on the B cell can determine whether a cell is triggered or tolerized after exposure to specific antigen (reviewed in 1,2). Ontogenic development of cell surface Ig in the murine system begins with the appearance of mIgM-bearing cells and is followed by cells expressing both mIgM and mIgD. Immature murine B lymphocytes display predominantly mIgM at the cell surface and constitute a population of lymphocytes that are readily tolerized. In contrast, mature B cells express both mIgM and mIgD on their surface. Exposure of these mature cells to antigen leads to subsequent proliferation and differentiation to antibody secretion. Furthermore, removal of mIgD from the surface of these mature lymphocytes (by treatment with papain or capping by specific antisera) results in a population of cells that becomes preferentially tolerized by antigen (2). Thus, the two classes of surface Ig, mIgM and mIgD, appear to regulate the response of B lymphocytes to antigen presentation.
KeywordsLight Chain Heavy Chain Immune Precipitate Glycoprotein Fraction Delta Chain
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- 2.Vitetta, E.S., et al. Biological Basis of Immunodeficiency, ed. Gelfand and Dosch. (1980) 189.Google Scholar
- 4.Sullivan, T. et al. This volume.Google Scholar
- 8.Cuatrecasas, P. J Biol Chem 245 (1970) 359.Google Scholar
- 10.Eidels, L. J Immunol 123 (1979) 846.Google Scholar
- 11.Finkleman, F.D. et al. J Immunol 116 (1976) 1173.Google Scholar