ROLE OF TRANSFORMING GROWTH-FACTOR-BETA-1 IN THE SUPPRESSED ALLOSTIMULATORY FUNCTION OF AIDS PATIENTS

Background: The T-cell stimulatory function of accessory cells isolate d from peripheral blood lymphocytes of AIDS patients has been reported to be suppressed. These patients also have elevated levels of the imm unosuppressive factor transforming growth factor (TGF)-beta 1 in their serum and plasma. Objective: To explore the role of TGF-beta 1 in the loss of accessory cell function of peripheral blood lymphocytes from AIDS patients. Methods: Fluorescent labeled anti-TGF-beta 1 and confoc al microscopy were used to detect the presence of TGF-beta 1 on the ce ll membrane of dendritic cells. To assess the role of TGF-beta 1 in th e inhibition of accessory cell function in AIDS, antibodies against TG F-beta 1 or the TGF-beta 1 type III receptor, beta-glycan, were added to a mixed lymphocyte reaction. Results: TGF-beta 1 was detected on th e cell membrane of dendritic cells isolated from AIDS patients. The ad dition of blocking antibodies against either TGF-beta 1 or beta-glycan restored the T-cell stimulatory function to accessory cells from thes e patients. Conclusions: T-cell stimulatory function was not irreversi bly lost in AIDS patients. Our data suggested that beta-glycan-TGF-bet a 1 immunosuppressive complexes may contribute to the suppression of a ccessory cell function in these patients. (C) 1998 Rapid Science Ltd.