IFNG and viral infectious disease: These IFNγ-producing, CD4+ T cells may help protect against HSK directly through the antiviral effects of the IFNγ they produce [52], or indirectly by limiting virus infection and inflammation in the corneal stroma and TG, by providing an environment rich in cytokines that reduce bystander activation, and/or by supporting the differentiation of HSV-specific CD8+ T cells in response to virus vaccine [53].