Is T-cell activation an unfavourable sign in i.v.-drug addicts infected with HIV?

In a longitudinal study, we examined 183 parenteral drug addicts who were imprisoned in Innsbruck, Austria, from March 1985 to March 1987. Thirty-seven percent of the patients had anti-HIV-antibodies. A 2-year follow-up of 43 seropositive patients revealed some evidence that urinary neopterin levels are of predictive value. Neopterin is produced from human macrophages upon stimulation with interferon gamma and, therefore, represents a sensitive parameter of activated T-cells. Eight patients who developed AIDS-related complex and one of them who contracted AIDS had significantly higher neopterin levels during the previous follow-up than the other groups of patients. Our data support the view that T-cell activation might be a crucial event in the induction of HIV reproduction in vivo.