T Cell Immunity and Zika Virus Vaccine Development.

The recent Zika virus (ZIKV) epidemic has created an urgent need for a safe and effective vaccine. There is still a dearth of knowledge about ZIKV immunity, but years of investigation into the immunobiology of other flaviviruses has helped to accelerate the development of a ZIKV vaccine. Although the humoral immune response generates the primary correlate of protection from disease, robust T cell responses could enhance ZIKV vaccine efficacy. Additionally, pre-existing immunity to related flaviviruses could generate cross-reactive T cells that may affect immune responses upon vaccination. In this review, we summarize the key discoveries in the area of flavivirus T cell immunity and postulate on how these findings can inform ZIKV vaccine strategies for inducing protective immunity.