The innate immune response in Zika virus infection

Zika virus (ZIKV; Flaviviridae, Flavivirus) was discovered in 1947 in Uganda, Africa, from the serum of a sentinel Rhesus monkey (Macaca mulatta). It is an enveloped, positive-sense, single-stranded RNA virus, which encodes a single polyprotein that is cleaved into 10 individual proteins. In 2015, the Zika-epidemic in Brazil was marked mainly by the exponential growth of microcephaly cases and other congenital defects. With regard to host-pathogen relationships, understanding the role of the immune response in the pathogenesis ZIKV infection is challenging. The innate immune response is the first-line immunological defence, in which pathogen-associated molecular patterns are recognized by pattern-recognition receptors that trigger macrophages, dendritic cells, natural killer cells and endothelial cells to produce several mediators, which modulate viral replication and immune evasion. In this review, we have summarized current knowledge on the innate immune response against ZIKV.