EFFECTS OF INTRAVENOUS IMMUNOGLOBULIN IN-VIVO ON ABNORMALLY INCREASEDTUMOR-NECROSIS-FACTOR-ALPHA ACTIVITY IN HUMAN-IMMUNODEFICIENCY-VIRUS TYPE-1 INFECTION

The effect of a single bolus injection (0.4 g/kg) of intravenous immun oglobulin (IVIG) on the tumor necrosis factor (TNF) system in human im munodeficiency virus type 1 (HIV-1)-infected patients was investigated . At 140 h after infusion, there was a significant decrease in levels of TNF-alpha and a significant increase in levels of soluble TNF recep tors (sTNFR) in both plasma and lipopolysaccharide-stimulated peripher al blood mononuclear cells (PBMC). A rapid (within 1 h) decline in exp ression of membrane-bound TNF-alpha and p55-TNFR on PBMC persisted thr oughout the study, In contrast, there was an increased expression of m embrane-bound p75-TNFR after 140 h. IVIG administration also resulted in significantly increased numbers of circulating CD4 lymphocytes, cor related with down-regulation of TNF-alpha activity in PBMC supernatant s. Thus, down-regulation of the abnormally increased TNF-alpha activit y may be achieved by IVIG administration. Studies evaluating the possi ble therapeutic role of long-term TNF-alpha suppression by IVIG may be warranted in HIV-1-infected patients.