Several aspects of keratitis, such as poor bacterial clearance, induction of pro-inflammatory cytokines and poor disease resolution manifested by Lum−/− mice are features shared by, and more pronounced in mice lacking major LPS signaling intermediates, TLR4 or MyD88 or transgenic Mafia mice after macrophage depletion [13], [28]. This evidence concerns the gene TLR4 and keratitis.