Functional reconstitution of an immunoglobulin antigen receptor in T cells.
Humoral immune responses are initiated by binding of antigen to the immunoglobulins (Igs) on the plasma membrane of B lymphocytes. On the cell surface, Ig forms a complex with several other proteins, two of which, MB-1 and B29, have been implicated in receptor assembly. We have reconstituted Ig receptor function in T lymphocytes by transfection of cloned receptor components. We found that efficient transport of IgM to the surface of T cells required coexpression of B29. Furthermore, IgM and B29 alone were sufficient to reconstitute antigen-specific signal transduction by Ig in the transfected T cells. Crosslinking of IgM with either antireceptor antibodies or antigen induced a calcium flux, phosphoinositol turnover, and interleukin secretion in T cells. These experiments establish a requirement for B29 in Ig receptor function, and suggest that the signaling apparatus of T and B cells is structurally homologous.
Costa
T E
TE
Howard Hughes Medical Institute, Rockefeller University, New York, New York 10021.
Franke
R R
RR
Sanchez
M
M
Misulovin
Z
Z
Nussenzweig
M C
MC
D000911:Antibodies, Monoclonal; D001402:B-Lymphocytes / Q000276:immunology*; D015152:Blotting, Northern; D002118:Calcium / Q000378:metabolism; D002460:Cell Line; D002462:Cell Membrane / Q000276:immunology / Q000378:metabolism; D003001:Cloning, Molecular; D004247:DNA / Q000235:genetics; D006801:Humans; D007075:Immunoglobulin M / Q000302:isolation & purification / Q000378:metabolism*; D007295:Inositol Phosphates / Q000378:metabolism; D007376:Interleukin-2 / Q000378:metabolism; D007700:Kinetics; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D011947:Receptors, Antigen, B-Cell / Q000235:genetics / Q000378:metabolism* / Q000502:physiology*; D015398:Signal Transduction; D013601:T-Lymphocytes / Q000276:immunology*; D014162:Transfection
D000911:Antibodies, Monoclonal; D007075:Immunoglobulin M; D007295:Inositol Phosphates; D007376:Interleukin-2; D012333:RNA, Messenger; D011947:Receptors, Antigen, B-Cell; D004247:DNA; D002118:Calcium