Event

Historically, vaccines have been designed to generate antigen-specific memory B and T cell responses that act rapidly upon antigen reencounter. Although control of TB requires T cells to prevent disease progression, multiple clinical trials, including the latest MVA85A using T cell targeted vaccine approaches have failed to provide protection against Mycobacterium tuberculosis (Mtb) infection. In addition, hyper-conserved Mtb genes involved in the production of immunodominant T cell epitopes have recently been described indicating that Mtb may paradoxically benefit from recognition by T cells. These results suggest that the concept of vaccines aimed at generating robust memory T cell responses for protection against TB needs to be profoundly revisited.