The Antimicrobial Peptide LL37 Induces the Migration of Human Pulp Cells: A Possible Adjunct for Regenerative Endodontics

IntroductionThe antimicrobial peptide LL37 has multiple functions, such as the induction of angiogenesis and migration. Pulp cell migration is a key phenomenon in the early stage of pulp-dentin complex regeneration. In this study, we examined the effect of LL37 on the migration of human pulp (HP) cells.MethodsHP cells at the sixth passage were exposed to LL37. The migration of HP cells was assessed by a wound-healing assay. The phosphorylation of epidermal growth factor receptor (EGFR) and c-Jun N-terminal kinase (JNK) was analyzed by immunoblotting.ResultsLL37 as well as heparin binding (HB)-EGF, which is an agonist of EGFR, induced HP cell migration. LL37 increased the level of phosphorylated EGFR. An anti-EGFR antibody, an EGFR tyrosine kinase inhibitor, and a JNK inhibitor abolished the migration induced by both LL37 and HB-EGF. Furthermore, the two peptides increased the levels of phosphorylated JNK.ConclusionsLL37 activates EGFR and JNK to induce HP cell migration, and it may contribute to enhancing the regeneration of pulp-dentin complexes.