The T-cell stimulatory function of accessory cells isolated from peripheral blood lymphocytes of AIDS patients has been reported to be suppressed. These patients also have elevated levels of the immunosuppressive factor transforming growth factor (TGF)-β1 in their serum and plasma.Objective:
To explore the role of TGF-β1 in the loss of accessory cell function of peripheral blood lymphocytes from AIDS patients.Methods:
Fluorescent labeled anti-TGF-β1 and confocal microscopy were used to detect the presence of TGF-β1 on the cell membrane of dendritic cells. To assess the role of TGF-β1 in the inhibition of accessory cell function in AIDS, antibodies against TGF-β1 or the TGF-β1 type III receptor, β-glycan, were added to a mixed lymphocyte reaction.Results:
TGF-β1 was detected on the cell membrane of dendritic cells isolated from AIDS patients. The addition of blocking antibodies against either TGF-β1 or β-glycan restored the T-cell stimulatory function to accessory cells from these patients.Conclusions:
T-cell stimulatory function was not irreversibly lost in AIDS patients. Our data suggested that β-glycan-TGF-β1 immunosuppressive complexes may contribute to the suppression of accessory cell function in these patients.