The role of Ia in the formation of a T cell antigen-recognition complex

T R Esch, D J McKean, D W Thomas
1990 Journal of Immunology  
We have evaluated the ability of a peptide-specific, I-Ak-restricted murine T hybridoma to bind its Ag in the presence and absence of class II MHC molecules. The restricting Ia molecule, when supplied as a plasma membrane preparation of I-Ak-expressing APC, specifically increases the avidity of the Ag-binding complex by lengthening its t1/2, without affecting the rate at which the complex is formed. Experiments using mutated I-Ak molecules indicate that the ability of a mutant Ia species to
more » ... ent Ag is distinct from its ability to stabilize the Ag-recognition complex, suggesting that T cell stimulation depends not only upon stabilization of Ag-TCR-Ia complexes, but also upon distinct Ia-influenced conformational signals.
doi:10.4049/jimmunol.145.12.3979 fatcat:bjgesefsdzaw5akw7m3ukgaz3i