HTLV-I-specific antibody in AIDS patients and others at risk.

Serum samples from 440 acquired immunodeficiency syndrome (AIDS) patients or individuals at risk for AIDS were examined by the enzyme-linked immunosorbent assay technique for antibodies to HTLV-I core proteins. Specific antibodies were detected in 7% of AIDS patients, 7% of patients with lymphadenopathy, 0% of healthy homosexual men, and 12% of healthy Haitians. When findings in homosexual men were analysed separately, the prevalence for homosexual men with lymphadenopathy was 7% and for homosexuals with AIDS, 6%. Antibody titres ranged from 77 to 74 000. The antibody-positive cases included intravenous drug users, a Haitian AIDS patient, a recipient of multiple blood transfusions, and homosexual men. Haemophiliacs were not examined. Although HTLV-I-specific antibodies are more prevalent in AIDS patients than in healthy US donors, the difference is not sufficient to suggest an association of HTLV-I with the disease. The low rate may indicate an opportunisitic infection of AIDS patients by HTLV-I, or a crossreaction with the recently described HTLV variant, HTLV-III, believed to be the aetiological agent of AIDS. Whether HTLV-I normally exerts immune suppressive effects in vivo with biological consequences remains to be determined.