the effect of exogenous interleukin 2 ( il 2 ) on lymphokine production by t lymphocytes was examined in two systems : the secretion of macrophage-activating factor ( maf ) and interferon ( ifn ) by cloned long-term t cell lines , and a limiting dilution system for estimating the frequency of precursors of maf-secreting cells in normal spleen .
C0007634
the
C1327616
secreting