TLR2 and periodontitis: C57BL/6, C57BL/6 J (WT, -TLR2(KO), -TLR4(KO), -TLR2,&4KO) mice, CD1 Swiss mice, C57BL/6 J female mice are some of the strains, and their knockouts that have been used in experimental periodontitis with microbes (54).