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Updated: Aug 13, 2025
Evaluation of Zika Virus-specific T-cell Responses in Immunoprivileged Organs of Infected Ifnar1-/- Mice
Published on: October 17, 2018
The pre-existing cellular immunity to Japanese encephalitis virus heterotypically protects mice from Zika virus
Weihong Zhang1, Yongfen Xu2, Fanfan Zhao3
1State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, China; CAS Key Laboratory of Molecular Virology and Immunology, Institut Pasteur of Shanghai, Chinese Academy of Sciences, Shanghai 200031, China; University of Chinese Academy of Sciences, Beijing 100049, China.
Abstract:
Zika virus (ZIKV) and Japanese encephalitis virus (JEV) are closely related flaviviruses, ZIKV circulates in the population that has been JEV vaccinated in Southeast Asian countries. This alerts that a pre-existing immunity to JEV would impact ZIKV infection and/or pathogenesis. Herein we showed that the pre-existing immunity to JEV SA14-14-2 vaccination provided an ample protection against non-lethal or lethal dose of ZIKV infection in mice. This was in sharp contrast to the passive immunization of JEV antibodies, which failed to affect ZIKV infection or pathogenesis in mice, albeit these antibodies exhibited cross-reactivity and antibody dependent enhancement (ADE) of ZIKV infection in vitro. Furthermore, we determined that JEV vaccine-elicited CD8+ T cells were required to mediate the heterotypic protection of ZIKV infection, which cross-reacted to ZIKV E and NS5 antigens (E294-302 and NS52839-2848). Adoptive transfer of these CD8+ T cells could partially protect the mice from ZIKV challenge. Therefore, although short of epidemiological evidence, these results suggested that cross-reactive CD8+ T cells activated by JEV vaccination could protect potential ZIKV infection in human populations.
