Comparative susceptibility of Old World and New World bat cell lines to Zika virus: Insights into viral replication and inflammatory responses

BackgroundFrom the first isolation of Zika virus (ZIKV) in Uganda in 1947, ZIKV had primarily been associated with sporadic human cases in Africa and Asia until ZIKV emerged as an epidemic in the Americas in 2015. As ZIKV spread into new geographic regions, it now has the potential to interact with many novel potential host species whose susceptibility to the virus has yet to be determined. Bats, with their ability to fly and live in or near human structures, are plausible ZIKV reservoirs. However, their competence as hosts for ZIKV remains unresolved. In this study, we investigate the immune response of Old World and New World bats to ZIKV infection in vitro. ResultsWe demonstrate that Egyptian Rousette bat (Rousettus aegyptiacus; Old World) cells are susceptible to ZIKV, while we observed little to no ZIKV replication in Jamaican fruit bat (Artibeus jamaicensis) cells. Notably, both the Asian and African ZIKV lineages elicited a strong proinflammatory response in the R. aegyptiacus cell line including upregulation of IL6, CXCL8, and CCL5. These data contrast with the dampened inflammatory response detected in these bats to other viruses. ConclusionsThe findings reveal that R06E cells derived from Egyptian Rousette bats exhibit robust proinflammatory and antiviral responses upon Zika virus (ZIKV) infection, characterized by significant upregulation of proinflammatory cytokines. This suggests that while these cells support productive ZIKV replication, they also mount a strong immune response, challenging the notion of these bats as immune-tolerant reservoirs and indicating a more complex interaction with the virus.