T-CELL HYBRIDOMA PRODUCTION OF MACROPHAGE ACTIVATION FACTOR (MAF) .1. SEPARATION OF MAF FROM INTERFERON-GAMMA

Abstract

A T cell hybridoma was developed [by fusing mouse thymoma BW5147 cells with mouse splenocytes] that produced macrophage activation factor (MAF) but no gamma interferon (IFN.gamma.). Hybridoma MAF was produced after stimulation with either concanavalin A (Con A) or phytohemagglutinin (PHA). Dose-response experiments showed that 1.5 .mu.g/ml Con A provided maximum MAF production with equivalent levels of MAF produced at Con A concentrations up to 6 .mu.g/ml. Time-course studies showed that maximum MAF activity was observed 48 h after mitogen stimulation, and titration of MAF-containing supernatants showed that maximal MAF activity was observed at 1:4 dilutions with significant activity present at dilutions as great as 1:64. No IFN.gamma. activity was detectable at any supernatant dilution.