Rapid induction of seven proteins in human lymphocytes by interferon; correlation to natural killer cell activity

The early effects of interferon (IFN) on the synthesis of protein in human nylon wool-nonadherent lymphocytes have been stimulated by use of two-dimensional electrophoresis. IFN-alpha or -beta as well as Escherichia coli-produced IFN-alpha 2 induced the rapid formation of seven proteins (Mr 80, 75, 62, 53, 38, 36, and 33 kD). At least five proteins were expressed within 2 hr of incubation with IFN. The synthesis of the seven proteins seemed to require rapid transcription of new RNA, because actinomycin D markedly inhibited their formation only when added less than 30 min after IFN. A good correlation was found between the ability of actinomycin D to inhibit both the formation of new proteins and the augmentation of natural killer (NK) cell activity. Screening of a panel of 10 hematopoietic and two anchorage-dependent cell lines revealed that p62 and p38 were induced in most cell lines, whereas p80 and p33 were preferentially induced in lymphoid cell lines. Three proteins could not be induced by IFN in any of the 12 cell lines, and thus could represent molecules mediating differentiated functions, possibly involved in NK cell function.