Comprehensive Immunoprofiling of Pediatric Zika Reveals Key Role for Monocytes in the Acute Phase and No Effect of Prior Dengue Virus Infection

Zika virus (ZIKV) is an emerging, mosquito-borne flavivirus responsible for recent epidemics across the Americas, and it is closely related to dengue virus (DENV). Here, we study samples from 46 DENV-naive and 43 DENV-immune patients with RT-PCR-confirmed ZIKV infection at early-acute, late-acute, and convalescent time points from our pediatric cohort study in Nicaragua. We analyze the samples via RNA sequencing (RNA-seq), CyTOF, and multiplex cytokine/chemokine Luminex to generate a comprehensive, innate immune profile during ZIKV infection. Immunophenotyping and analysis of cytokines/chemokines reveal that CD14⁺ monocytes play a key role during ZIKV infection. Further, we identify CD169 (Siglec-1) on CD14⁺ monocytes as a potential biomarker of acute ZIKV infection. Strikingly distinct transcriptomic and immunophenotypic signatures are observed at all three time points. Interestingly, pre-existing dengue immunity has minimal impact on the innate immune response to Zika. Finally, this comprehensive immune profiling and network analysis of ZIKV infection in children serves as a valuable resource. At three time points after Zika virus infection, Michlmayr et al. perform comprehensive immunoprofiling of pediatric cohort samples via RNA-seq, CyTOF, and Luminex cytokine/chemokine array, resulting in distinct temporal patterns of gene expression, cell profiles, and cytokines/chemokines. They show CD14⁺ monocytes play a central role, identify CD169 as a potential biomarker of acute ZIKV infection along with upregulation of CXCL10, and find no impact of prior dengue virus infection on the innate immune response to Zika.