MACROPHAGE RELEASE OF TUMOR-NECROSIS-FACTOR-ALPHA BY MYCOBACTERIUM-AVIUM ANTIGENS

Mycobacterium avium complex (MAC) infection is the most common dissemi nated opportunistic infection encountered in patients with AIDS. We ha ve studied the ability of specific Mycobacterium avium (MA) antigens. to stimulate human monocyte-derived macrophages (MDM) to produce tumor necrosis factor-alpha (TNF-alpha). MDM stimulated with MA sonicate, M A 68 kDa and MA 48-52 kDa antigens were found to produce TNF-alpha in a dose-dependent manner. Reverse transcriptase-polymerase chain reacti on analysis of mRNA extracts from antigen-stimulated MDM indicated tha t TNF-alpha mRNA expression was of brief duration and the time point o f peak TNF-alpha mRNA levels was found to be antigen-specific. A signi ficant difference in TNF-alpha production in response to MA 48-52 kDa antigen and M. bovis 65 kDa antigen was observed between MDM from norm al and HIV positive individuals.