CD4 and infection: In addition, infection with a high dose of the Erdman Mtb strain by intravenous administration (1 × 105 CFU), or the intranasal administration (1 × 105 CFU) of Mtb strain H37Rv produced higher bacterial burdens in TLR4-deficient C3 H/HeJ mice than TLR4-competent C3 H/HeN mice, along with severe lung inflammation and decreased numbers of CD4+IFN-γ+ T cells after 2 weeks of infection [20,38].