Anti-Immunoglobulin Stimulation of Murine Lymphocytes

• Published in: The Journal of immunology (1950) Vol. 117; no. 5_Part_1; pp. 1527 - 1531
• Main Authors: Weiner, Howard L., Moorhead, John W., Yamaga, Karen, Kubo, Ralph T.
• Format: Journal Article
• Language: English
• Published: 01.11.1976
• ISSN: 0022-1767; 1550-6606
• DOI: 10.4049/jimmunol.117.5_Part_1.1527

Abstract Splenic B cells from normal mice, 7 months of age or older, can be stimulated to proliferate in vitro with soluble anti-immunoglobulin (Ig) reagents. To investigate whether the integrity of the anti-Ig molecule is necessary for stimulation and to determine whether cross-linkage of cell surface Ig is required, experiments were done by using F (ab′)2 fragments and Fab monomers prepared from anti-MIgM serum. To determine whether antibodies directed against heavy chains would induce cell proliferation, class-specific antisera were prepared and tested. The results showed that cell proliferation was induced by F (ab′)2 fragments but not by Fab monomers. In addition, cell proliferation was obtained with monospecific antiserum directed against µ heavy chains but not with antisera directed against α- or γ- chains. Thus cross-linkage of µ heavy chains on the B cell surface is required for soluble anti-Ig-induced proliferation. Further experiments were done to investigate the nature of the age-associated response by comparing membrane immunoglobulin density and class on spleen cells from old and young (2 to 3 months) mice; no differences in surface immunoglobulins were found which would explain the age-associated response to anti-Ig reagents.