In order to study the local immune response to HIV2, three exclusively heterosexual, infected West African patients were selected: one male with full blown AIDS, one female with ARC and one healthy HIV2-carrier female. Sera and genital secretions were obtained and tested for anti-HIV2 IgG and IgA antibodies by Western blotting. In semen and in vaginal secretions, IgG antibodies directed against all viral antigens were detected. In comparison with the IgG response, local IgA antibody response was less intense and heterogenous. Two out of 3 patients had local antibodies of the IgA class directed against the envelope glycoprotein GP105. Such antibodies of both the IgG and IgA classes in genital secretions could play a protective role in heterosexual transmission of HIV2.