T-CELL FUNCTIONS ARE IMPAIRED BY INHALED ISOBUTYL NITRITE THROUGH A T-INDEPENDENT MECHANISM

Isobutyl nitrite is representative of a group of inhalants abused by m ale homosexuals and adolescents. inhalation exposure of mice to isobut yl nitrite at 900 ppm for 45 min per day for 14 days caused serious de ficits in T cell-mediated immune responses. Cytotoxic T lymphocyte (CT L) activity was reduced by 36% following the exposure. T cell prolifer ative responses to mitogenic and allogeneic stimulation were reduced b y 37% and 51%, respectively. The exposure did not directly alter the a bility of T cells to synthesize or respond to IL-2. Accessory cell fun ction in facilitating T cell activation was inhibited by about 50% fol lowing exposure to the inhalant.