Cross-reactive antibodies with the capacity to mediate HIV-1 envelope glycoprotein-targeted antibody-dependent cellular cytotoxicity identified in HIV-2-infected individuals

Disease progression of human immunodeficiency virus type 1 (HIV-1) is delayed by HIV type 2 (HIV-2) in individuals with dual HIV-1/HIV-2 infection. The protective mechanisms, however, are still to be revealed. In the current study we examined type-specific and cross-reactive antibody-dependent cellular cytotoxicity (ADCC) in HIV-1 and HIV-2 monoinfection or dual infection. Of note, intertype cross-reactive antibodies that mediated HIV-1 envelope glycoprotein (Env)-targeted ADCC were frequently identified in HIV-2-infected individuals. Furthermore, the magnitude of HIV-1 cross-reactive ADCC activity during HIV-2 infections depended on the HIV-1 Env origin and was associated with the duration of infection. These results suggest that preexisting antibodies against HIV-2, which mediate intertype ADCC, might contribute to control of HIV-1 during dual infection.