The Antimicrobial Peptide Esculentin-1a(1-21)NH2: A Novel Promoter of Human Skin Wound Healing?

Antimicrobial peptides (AMPs) are produced by all living organisms as a first line defense against invading microorganisms. In Amphibia, they are mainly present in the skin to form a protective chemical barrier between tissues and external environment. Esculentin-1a(1-21)NH2 [Esc(1-21)] is an amphibian skin-derived AMP with a broad spectrum of activity [1]. Unlike the human skin AMP LL-37, Esc(1-21) preserves its antimicrobial activity in biological fluids and is significantly less toxic at high concentrations. By using an in vitro modified scratch assay employing special cell-culture inserts, we found that Esc(1-21) significantly stimulates migration, but not proliferation, of immortalized human keratinocytes (HaCaT cells), more efficiently than LL-37. Importantly, this activity is preserved also on primary human epidermal keratinocytes [2]. Moreover, as previously shown for LL-37, we demonstrated that the Esc(1-21)-induced cell migration involves the activation of the epidermal growth factor receptor and STAT3 protein. Typical morphological changes associated with a migratory phenotype were detected in HaCaT cells upon treatment with Esc(1-21) [2]. These results focus on the wound healing-modulatory properties of Esc(1-21) and suggest it as a novel candidate promoter of skin re-epithelialisation, especially in the management of chronic human skin ulcers.