Upon antigen stimulation , precursor CD4+ T helper ( pTh ) cells proliferate and differentiate into two populations of effector cells ( eTh1 and eTh2 ) , each one expressing a specific pattern of cytokines that distinguishes them from their precursors .
upon antigen stimulation , precursor cd4+ t helper ( pth ) cells proliferate and differentiate into two populations of effector cells ( eth1 and eth2 ) , each one expressing a specific pattern of cytokines that distinguishes them from their precursors .
O O O O O B-cell_type I-cell_type I-cell_type I-cell_type I-cell_type I-cell_type I-cell_type O O O O O O O B-cell_type I-cell_type O B-cell_type O B-cell_type O O O O O O O O O B-protein_family_or_group O O O O O O O