By contrast, compared with the normal group, the levels of nitric oxide, IL-2, IL-6, IL-17A, TNF and IFN-γ were increased in the PCP-treated mice, indicating that PCP can activate the TLR4/TRAF6/NF-κB signaling pathway to mediate immunomodulatory activity [44]. Here, TRAF6 is linked to pneumocystosis.