TNF and infection: Both of these cytokines have been shown to play an important role in defense against R. conorii. The neutralization of either IFNγ or TNFα leads to enhanced pathology in R. conorii-infected C3H/HeN mice, and IFNγ-deficient C57BL/6 mice succumb to the infection with a normally sublethal dose of R. conorii [101].