TLR4 and lupus nephritis: Using transgenic mouse called TCr-5, whose genome contains multiple copies of the tlr4 gene on a TLR4-deficient C57/BL10ScCr (deletion of tlr4 gene and point mutation in IL-12Rβ 2gene) background, it has been shown that up-regulation TLR4 is pathogenic both at the protein level and gene level and triggered spontaneous SLE-like autoimmunity and lupus nephritis [8].