Altered immunity in hemophilia correlates with the presence of antibody to human T-cell lymphotropic virus type III (HTLV-III).

Twenty-nine heterosexual patients with hemophilia were investigated with histories, physical examinations, laboratory evaluations of immune function, delayed hypersensitivity skin tests, and assays for antibody to human T-cell lymphotropic virus type III (HTLV-III). Sixteen patients were HTLV-III antibody positive and 13 were HTLV-III antibody negative. No patient had the acquired immune deficiency syndrome (AIDS). Patients who had antibody to HTLV-III had received significantly more units and lots of factor concentrates in the preceding 5 years than those who did not have antibody. HTLV-III antibody-positive patients had significantly fewer total T cells (Leu-1 positive) and significantly fewer helper T cells (Leu-3 positive) than HTLV-III negative patients. Antibody-positive patients also had increased amounts of IgG and decreased thymidine incorporation in response to concanavalin A in vitro. There were no differences in in vitro lymphocyte responses to phytohemagglutinin (PHA), pokeweed mitogen, Candida, tetanus, or purified protein derivative (PPD), no significant impairments of gamma interferon or interleukin-2 (IL-2) production, and no anergy. Ten patients with antibody to HTLV-III had immunologic studies repeated 1 year after the original evaluation. A significant increase was seen in suppressor (Leu-2-positive) T cells but not in total T-cell or helper T-cell numbers, helper/suppressor ratios, or T-cell functional assays. We conclude that the immune abnormalities in hemophiliacs are the result of contact with HTLV-III but that these abnormalities may remain stable over prolonged periods.