Enhancing the effectiveness of anti-respiratory virus vaccines by bolstering mucosal immunity and cellular defenses.

A schematic diagram of intratracheal (IT) boosting, which leads to enhanced mucosal immunity and protective efficacy. IT boosting leads to significant expansion of mucosal neutralizing antibodies, along with robust CD8 and CD4 T-cell responses. Notably, IT boosting results in substantial and sustained activation of cytokine, natural killer, T, and B-cell pathways in the lung, contributing to enhanced mucosal immunity and overall protective efficacy.