MyD88 is also essential for TLR2 and TLR4 signaling, yet the role of TLR2 and TLR4 is not clear in the development of corneal opacification; TLR4−/− mice have an impaired ability to clear the infection so TLR4−/− is important in eradicating fungal infection. This evidence concerns the gene TLR4 and fungal infectious disease.