Fig 3. Systemic and lung cytokine and chemokine levels in LCR and HCR rats infected with S. aureus.
LCR rats (Circles) and HCR rats (Squares) were challenged IV with S. aureus (n = 7/group). Levels of IL-6, IL-10, MIP-2, and 1L-17A were quantified in the serum, BALF, and lung homogenates 48 h after challenge with S. aureus. Compared with infected HCR rats, infected LCR rats had higher levels of IL-6 in plasmas, BALF and lung homogenates (**p = 0.007, **p = 0.0006, and *p = 0.0262, respectively), higher levels of MIP-2 in plasmas and lung homogenates (**p = 0.004 and **p = 0.0006, respectively), and higher levels of IL-17A in lung homogenates (**p = 0.0006). In contrast, compared with infected HCR rats, infected LCR rats had lower levels of IL-10 in plasmas, BALF and lung homogenates (**p = 0.007, ***p = 0.0006, and **p = 0.0041, respectively). The figures show levels of cytokines after subtracting out the values measured in control rats treated with sterile saline from the values measured in rats treated with S. aureus (i.e.: cytokine value shown on Y axis for LCR rats = cytokine level of LCR with S. aureus infection—cytokine level of LCR rat treated with sterile saline, similarly for HCR rats). Data were analyzed using Mann Whitney U tests; results are expressed as median with interquartile range. HCR = high capacity runner; LCR = low capacity runner; BALF = bronchoalveolar lavage fluid; IL = interleukin; MIP = macrophage inflammatory protein.
