The cognate interaction between T cells and antigen-presenting cells ( APCs ) , mediated by major histocompatibility complex ( MHC ) class II molecules , results in the delivery of activation signals to the APC .
the cognate interaction between t cells and antigen-presenting cells ( apcs ) , mediated by major histocompatibility complex ( mhc ) class ii molecules , results in the delivery of activation signals to the apc .
O O O O B-cell_type I-cell_type O B-cell_type I-cell_type O B-cell_type O O O O B-protein_family_or_group I-protein_family_or_group I-protein_family_or_group I-protein_family_or_group I-protein_family_or_group I-protein_family_or_group I-protein_family_or_group I-protein_family_or_group I-protein_family_or_group O O O O O O O O O O B-cell_type O