Engineering of Lactobacillus jensenii to secrete RANTES and a CCR5 antagonist analogue as live HIV-1 blockers.

The development of effective microbicides for the prevention of HIV-1 sexual transmission represents a primary goal for the control of AIDS epidemics worldwide. A promising strategy is the use of bacteria belonging to the vaginal microbiota as live microbicides for the topical production of HIV-1 inhibitors. We have engineered a human vaginal isolate of Lactobacillus jensenii to secrete the anti-HIV-1 chemokine RANTES, as well as C1C5 RANTES, a mutated analogue that acts as a CCR5 antagonist and therefore is devoid of proinflammatory activity. Full-length wild-type RANTES and C1C5 RANTES secreted by L. jensenii were purified to homogeneity and shown to adopt a correctly folded conformation. Both RANTES variants were shown to inhibit HIV-1 infection in CD4(+) T cells and macrophages, displaying strong activity against HIV-1 isolates of different genetic subtypes. This work provides proof of principle for the use of L. jensenii-produced C1C5 RANTES to block HIV-1 infection of CD4(+) T cells and macrophages, setting the basis for the development of a live anti-HIV-1 microbicide targeting CCR5 in an antagonistic manner.