IL4 and infection: The activated SPY1-specific Treg immune response maintained the beneficial immune balance among the infection-associated inflammatory cytokine TNF-α, immune cytokines IL-6, IL-12p70, IL-4, IL-5, and IL-17A, as well as the immunoregulatory cytokine IL-10, and further alleviated excessive pulmonary injury, resulting in decreased bacterial colonization, elevated survival rates, and prolonged survival.