After high-dose infection (5 × 106 CFU per mouse), bronchoalveolar lavage fluid (BALF) TNF levels recovered at 2 h and IL-1β and IL-6 at 4 h were higher in response to the TIGR4 strain compared to infection with the TIGR4 Δcps strain (Fig. 5A to C). This evidence concerns the gene IL1B and infection.