IL17A and infection: To determine the profile of inflammatory cells and IL-17A cellular sources in the lungs after infection with either poorly or highly virulent strains of M. bovis, lungs were collected at different days post-infection to obtain cellular suspensions and determine the number of CD11B+ Ly6G+ neutrophils, IL-17A+ neutrophils, and CD3+ CD8+ IFN+ lymphocytes (cytotoxic lymphocytes) by cytofluorometry (Fig 3).