Abstract
Previous findings suggest that during cognate T cell-B cell interactions, major histocompatability complex (MHC) class II molecules transduce signals, leading to Src-family kinase activation, Ca2+ mobilization, and proliferation. Here, we show that antigen stimulation of resting B cells induces MHC class II molecules to associate with Immunoglobulin (Ig)-alpha/Ig-beta (CD79a/CD79b) heterodimers, which function as signal transducers upon MHC class II aggregation by the T cell receptor (TCR). The B cell receptor (BCR) and MHC class II/Ig-alpha/Ig-beta are distinct complexes, yet class II-associated Ig-alpha/beta appears to be derived from BCR. Hence, Ig-alpha/beta are used in a sequential fashion for transduction of antigen and cognate T cell help signals.
Publication types
-
Research Support, Non-U.S. Gov't
-
Research Support, U.S. Gov't, P.H.S.
MeSH terms
-
Animals
-
Antigens / immunology
-
Antigens, CD / metabolism*
-
B-Lymphocytes / immunology*
-
B-Lymphocytes / metabolism
-
CD79 Antigens
-
Cells, Cultured
-
Dimerization
-
Enzyme Activation
-
Histocompatibility Antigens Class II / immunology
-
Histocompatibility Antigens Class II / metabolism*
-
Immunoblotting
-
Lymphocyte Activation
-
Mice
-
Mice, Transgenic
-
Phosphorylation
-
Phosphotyrosine / metabolism
-
Precipitin Tests
-
Protein-Tyrosine Kinases / metabolism
-
Receptors, Antigen, B-Cell / immunology
-
Receptors, Antigen, B-Cell / metabolism*
-
Receptors, Antigen, T-Cell / immunology
-
Receptors, Antigen, T-Cell / metabolism*
-
Signal Transduction*
-
T-Lymphocytes / immunology
-
T-Lymphocytes / metabolism
-
Transcription, Genetic
Substances
-
Antigens
-
Antigens, CD
-
CD79 Antigens
-
Cd79a protein, mouse
-
Cd79b protein, mouse
-
Histocompatibility Antigens Class II
-
Receptors, Antigen, B-Cell
-
Receptors, Antigen, T-Cell
-
Phosphotyrosine
-
Protein-Tyrosine Kinases