Lum FM, et al. - The unexpected re-emergence of Zika virus (ZIKV) has caused numerous outbreaks globally. This is the first comprehensive study undertaken by researchers to characterize the host immune responses during ZIKV infection. During ZIKV disease progression, specific cellular changes and immune signatures were noted, providing valuable insights into ZIKV immuno-pathogenesis.

Methods

• During the Singapore outbreak in late 2016, researchers collected patient samples longitudinally during the acute, convalescence and recovery phases of ZIKV infection over 6 months.
• They profiled plasma immune mediators via multiplex micro-bead assay and determined changes in blood cell numbers with immune-phenotyping.

Results

• Various immune mediators were noted to be involved during acute ZIKV infection; this was accompanied by a general reduction in blood cell numbers for all immune subsets except CD14+ monocytes.
• Viremic patients experiencing moderate symptoms exhibited markedly higher quantities of IP-10, MCP-1, IL-1RA, IL-8 and PIGF-1, accompanied by reduced numbers of peripheral CD8+, CD4+ and DNT cells.
• In recovery phases of ZIKV infection, levels of T-cell associated mediators including IP-10, IFN&gamma, and IL-10 were high, suggesting a functional role for T-cells.
• Researchers identified different markers at specific disease phases emphasizing the dynamics of a balanced cytokine environment in disease progression.