The Effect of Antimicrobial Peptides on the Viability of Human Corneal Epithelial Cells

Antimicrobial peptides are polypeptides composed of less than 100 amino acids and are a class of antibiotics with strong activity against some infectious bacteria. This study examined the safety of four chosen antimicrobial peptides using primary human corneal epithelial cells (HCEC) and explored their potential therapeutic use. The efficacy of the peptides was also studied by evaluating the minimum inhibitory concentrations (MIC) against Gram-negative and Gram-positive bacteria. One of the peptides (polymyxin E) was found to have antibacterial efficacy against a common Gram-negative bacterium (MIC 1.56 mu g/mL forPseudomonas aeruginosa), and another one (nisin) was found to have antibacterial efficacy against a common Gram-positive bacterium (MIC 125 mu g/mL forStaphylococcus aureus). Metabolic activity and live/dead/apoptotic effects were measured with fluorescent dyes after HCEC were exposed to the peptides for 30 min. Three of the peptides exhibited lower toxicity against HCEC than a currently marketed eye drop product. Regarding both efficacy and safety, two of the peptides (polymyxin E and nisin) were found to have potential use for treating ocular infections.

Automated summary

Antimicrobial peptides are a class of polypeptides composed of less than 100 amino acids, demonstrating strong activity against infectious bacteria. Among the peptides studied, polymyxin E and nisin showed potential for treating ocular infections with low toxicity to human corneal epithelial cells.