Nontypeable <i>Haemophilus influenzae</i>specific memory T H17 cells protect against secondary bacterial pneumonia following Influenza A virus infection

Abstract Nontypeable Haemophilus influenzae(NTHi) is one of the most common bacteria that cause secondary bacterial pneumonia following influenza A virus (IAV) infection, leading to hospitalization and death associated with IAV infection worldwide. Current efforts develop vaccines against NTHi focus on inducing antibodies but are hindered by antigenic diversity among strains. Therefore, we interrogated contribution memory T-helper type 17 (T H17) response in protective immunity IAV/NTHi co-infection. We observed co-infected mice exhibited prolonged lungs even at mild impaired NTHi-specific T H17 responses compared mono-infected mice. However, immune recovered from a prior were protected homologous heterologous strains infection. Our data further revealed cells overcame IAV-driven impairments anti-NTHi cross-reactive different Last, immunized protein induced strong broadly diverse challenge These results indicate capable providing serotype-independent protection co-infection demonstrate advantage developing H17-inducing pneumonia.