IL17A and susceptibility to pneumonia measurement: As previously noted, Th1 effector cytokines such as IFN-γ may play a crucial role in the eradication of S. aureus60, 61, while Th17/IL-17 pathway may collaborate in promoting neutrophil recruitment62, and was demonstrated to be essential for combating S. aureus sepsis and pneumonia in mice8, 63, 64, 65.