Effect of ano-receptive homosexual practice on T lymphocytes and delayed hypersensitivity in transsexuals.

To determine whether ano-receptive sexual intercourse adversely affects a person's cellular immunity, we compared several immunological parameters among 100 transsexual male prostitutes and 40 heterosexual male controls, and also among different durations of prostitution. The mean ratios of CD-4 (helper/inducer) lymphocytes to CD-8 (suppressor/cytotoxic) lymphocytes and the delayed-type cutaneous hypersensitivity (DTH) scores were significantly lower in transsexuals than they were in heterosexual controls; these parameters also showed a decreasing trend with increasing duration of prostitution. Transsexuals have a significantly higher CD-8 lymphocyte count than have heterosexuals. No significant differences between transsexuals and heterosexuals were found for lymphocyte counts, pan T cells, and CD-4 cell counts. We postulate that in these subjects cellular immunity is progressively reduced, probably through repeated and prolonged antigenic challenge via receptive anal intercourse. The impairment in cellular immunity is associated with the duration of prostitution, independent of the man's age.