Two types of helper T cell ( Th ) clones ( Th1 and Th2 ) are defined on the basis of different patterns of cytokine ( lymphokine ) secretion .
two types of helper t cell ( th ) clones ( th1 and th2 ) are defined on the basis of different patterns of cytokine ( lymphokine ) secretion .
O O O B-cell_line I-cell_line I-cell_line I-cell_line I-cell_line I-cell_line I-cell_line O B-cell_line O B-cell_line O O O O O O O O O O B-protein_family_or_group O B-protein_family_or_group O O O