DEFB1 and keratitis: While P. aeruginosa caused a significant decrease in Rnase7 expression, there was increased expression of the same by S. pneumoniae. The expression of hBD4 was not detected in any patient samples or in vitro during P. aeruginosa infection; on the contrary, expression of hBD4 was found in both patient samples and in HCECs in response to S. pneumoniae. Decreased expression of hBD1 was also seen in S. pneumoniae corneal infections compared to elevated expression of the same during P. aeruginosa keratitis.