Immunological study of the rectal mucosa of men with and without human immunodeficiency virus infection.

Biopsies of rectal mucosa were taken from 81 men and stained using cytochemical methods for B and T lymphocytes, T cell subsets, immunoglobulin containing plasma cells and mucosal mast cells. The patients studied included human immunodeficiency virus (HIV) infected and non-infected heterosexual and homosexual men, and homosexual men with rectal gonorrhoea. There were increased numbers of T lymphocytes in the lamina propria of the rectum in HIV infected individuals regardless of whether the infection had been acquired through anal intercourse or intravenous drug use. This increase resulted from a marked increase in the numbers of CD8+ suppressor T cells, there also being a reduction in the numbers of CD4+ helper T cells. In non-HIV infected men with rectal gonorrhoea there were increased numbers of CD8+ T cells but no significant difference in numbers of CD4+ cells. No difference was seen in numbers of CD4+ cells. No difference was seen in numbers of immunoglobulin containing plasma cells or mucosal mast cells between HIV infected and non-infected men.