Pre-existing YFV-17D immunity mediates T cell cross-protection against dengue virus serotype 2 infection in mice.

ABSTRACT: Widespread yellow fever virus (YFV) immunity in Sub-Saharan Africa may mitigate orthoflavivirus outbreaks. Here, we investigate whether pre-existing YFV-17D immunity confers cross-protection against dengue virus serotype 2 (DENV-2) infection in a murine model. IFNAR1^-/- mice immunized with YFV-17D exhibited significantly reduced DENV-2 viremia, weight loss, and disease severity, with improved survival compared to naïve controls. Mechanistic studies revealed that cross-protection was mediated by heterologous T cell responses rather than cross-binding antibodies. Depletion of T cells in YFV-17D-immune mice prior to DENV-2 challenge resulted in increased viremia, weight loss, and disease severity, underscoring the protective role of YFV-17D-elicited T cell immunity. Furthermore, YF

SUBMITTER: Tonto PB 

PROVIDER: S-EPMC12405563 | biostudies-literature | 2025 Sep

REPOSITORIES: biostudies-literature