TLR4 and infection: TRAIL-R-deficient mice develop normal populations of immune cells [33], [39], [40], but challenge of these mice with different pathogens and stimuli for TLR2, TLR3 and TLR4 results in enhanced ability of the innate immune system to clear the infection and increased production of different pro-inflammatory-cytokines such as IFN-β, compared to wildtype mice [33].