Novel corneal targeting cell penetrating peptide as an efficient nanocarrier with an effective antimicrobial activity

Delivery of therapeutics to the ocular tissues is challenging due to various anatomical and physiological barriers imposed. Cell penetrating peptides (CPPs) have emerged as potent drug nanocarriers that have been shown to overcome these barriers and enhance bioavailability of therapeutic macromolecules in deep ocular tissues. In the present study, an ocular targeting CPP has been designed by exploring potential targets of anterior ocular tissues in particular receptors, transporters and glycosaminoglycans (GAGs). The novel 11 mer peptide sequence, Corneal Targeting Sequence 1 (CorTS 1), has been developed by modifying leucine rich repeat (LRR) motif ensuring that it interacts with small leucine rich proteoglycans and collagen present in the corneal stroma. CorTS 1 exhibited dose dependent cellular translocation from 5 μM in Human Corneal Epithelial cell line (HCE) with no cytotoxicity. CorTS 1 was also found to deliver protein cargo inside HCE cells. Ex vivo tissue penetration study of CorTS 1 demonstrated in goat eyes revealed an augmented accumulation of peptide in the stromal region of cornea than in aqueous humor. Interestingly, CorTS 1 showed an antimicrobial activity against MRSA and Fusarium dimerum. Therefore, CorTS 1 can be a promising candidate with dual traits of antimicrobial agent and nanocarrier for ocular drugs.