Toxicity of sulfonamide-reactive metabolites in HIV-infected, HTLV-infected, and noninfected cells

J Acquir Immune Defic Syndr Hum Retrovirol. 1995 Feb 1;8(2):134-40.


It has been suggested that the high rates of adverse reactions to sulfonamides among patients with AIDS may be related to an increased sensitivity to reactive drug metabolites among HIV-infected cells. To study this hypothesis, we investigated the toxicity of the hydroxylamine of sulfamethoxazole in HIV-infected and noninfected MOLT-3 cultured human T-lymphoblasts. Toxicity was assessed by trypan blue dye exclusion. The hydroxylamine of sulfamethoxazole produced concentration-dependent toxicity in HIV-infected cells, with marked toxicity seen when HIV-infected cells were incubated with 400 microM of the hydroxylamine (82 +/- 8%); this was significantly greater than the toxicity seen among noninfected cells (p < 0.01). There was no concentration-dependent toxicity seen among noninfected cells or in cells infected with HTLV-I, suggesting that the concentration-dependent toxicity seen was specifically related to HIV infection. HIV-infected cells had significantly lower glutathione concentration than did noninfected cells (p < 0.05). Incubation with the hydroxylamine of sulfamethoxazole produced a concentration-dependent decline in glutathione content that was similar in infected and non-infected cells. Co-incubation with glutathione or N-acetylcysteine significantly reduced the toxicity of hydroxylamine of sulfamethoxazole in HIV-infected cells (p < 0.05). Our data supports the role of reactive sulfonamide metabolites in the pathogenesis of adverse reactions to sulfonamides among patients with AIDS.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Cells, Cultured
  • Deltaretrovirus Infections / drug therapy*
  • Dose-Response Relationship, Drug
  • Drug Hypersensitivity / etiology
  • HIV Infections / drug therapy*
  • Humans
  • Models, Biological
  • Sulfamethoxazole / analogs & derivatives*
  • Sulfamethoxazole / toxicity
  • T-Lymphocytes / drug effects*
  • T-Lymphocytes / virology
  • Toxicity Tests


  • sulfamethoxazole hydroxylamine
  • Sulfamethoxazole