Infection order outweighs the role of CD4 T cells in tertiary flavivirus exposure.

The link between CD4 T and B cells during immune responses to DENV and ZIKV and their roles in cross-protection during heterologous infection is an active area of research. Here we used CD4 lymphocyte depletions to dissect the impact of cellular immunity on humoral responses during a tertiary flavivirus infection in macaques. We show that CD4 depletion in DENV/ZIKV-primed animals followed by DENV resulted in dysregulated adaptive immune responses.

Time elapsed between Zika and dengue virus infections affects antibody and T cell responses.

Zika virus (ZIKV) and dengue virus (DENV) are co-endemic in many parts of the world, but the impact of ZIKV infection on subsequent DENV infection is not well understood. Here we show in rhesus macaques that the time elapsed after ZIKV infection affects the immune response to DENV infection. We show that previous ZIKV exposure increases the magnitude of the antibody and T cell responses against DENV.