tokens: We have tested this possibility directly using TAP-deficient cell lines lacking antigenic ER peptides derived from two model Ags , the human adenovirus type 5 early regions E1A and E1B .
folded_tokens: we have tested this possibility directly using tap-deficient cell lines lacking antigenic er peptides derived from two model ags , the human adenovirus type 5 early regions e1a and e1b .
labels: O O O O O O O B-cell_line I-cell_line I-cell_line O B-peptide B-cell_component O O O O O B-protein_family_or_group O O O O O O O O O O O O