Maternal immune status influences HIV-specific immune responses in pups after DNA prime protein boost using mucosal adjuvant

This study was designed to determine the impact of maternal HIV-1 specific immunity on HIV-DNA immunization of 2-week-old pups during the breast-feeding period.Adult female mice received intranasal or intradermal HIV-DNA (gp160Env, p37Gag, Nef, Tat and Rev) prime and recombinant protein boost immunizations, which induced mucosal and systemic HIV-1 specific B and T cell responses. Intranasal administration of the immunogens induced higher serum IgG titers to HIV antigens than intradermal immunization. Furthermore, high HIV-1 specific fecal IgA titers were obtained in mice immunized by intranasal administration. The capacity to respond to the same immunogens (one single prime with DNA and one boost with recombinant protein) was then compared in pups born to mothers with HIV-1-specific immune responses and pups born to non-vaccinated mothers. Immune responses to the largest number of antigens were detected in pups born to mothers with the highest HIV-1-specific immune responses. These data show that HIV-1 DNA-plasmid immunization during breast-feeding and recombinant protein boosting shortly thereafter enhance the breadth of humoral HIV-1-specific immune responses.