Innate gamma/delta T-cells during HIV infection: Terra relatively incognita in novel vaccination strategies?

Despite a long-lasting global effort, the Holy Grail quest for a protective vaccine, able to confer prevention to HIV infection, did not reach the hoped for results, nor seems able to do so in the near future. Since mucosal surfaces of the host serve as the main entry point for HIV, it seems now logical to switch from a systemic to a localized view of events, in order to reveal critical steps useful in designing new and different vaccination strategies. In this context, the recent description of the very early phases of infection, from the eclipse to the viremia peak phase, seems to define a point-of-no-return threshold after which the main HIV infection steps, i.e. the massive destruction of the CD4+CCR5+ cell pool, the destruction of the mucosal physical barrier, and the establishment of reservoir sanctuaries, have already been accomplished. Nevertheless, the underlying mechanisms, the timing, and the consequences of evasion mechanisms exploited by HIV are still under scrutiny. Innate immunity, as part of a rapid lymphoid stress surveillance system, is known to play a central role in host responses to many infectious agents. In particular, V