The T cell surface molecule CD28 binds to ligands on accessory cells and APCs , playing an important costimulatory role in the response of T cells to Ags .
the t cell surface molecule cd28 binds to ligands on accessory cells and apcs , playing an important costimulatory role in the response of t cells to ags .
O B-protein_family_or_group I-protein_family_or_group I-protein_family_or_group I-protein_family_or_group B-protein_molecule O O O O B-cell_type I-cell_type O B-cell_type O O O O O O O O O O B-cell_type I-cell_type O B-protein_family_or_group O