The human host defense peptide LL37/hCAP accelerates angiogenesis in PEGT/PBT biopolymers

Antimicrobial peptides are effector molecules of the innate immune response and contribute to host defense and inflammation. This study was designed to evaluate neovascularization in biopolymers after instillation with LL37 of angiogenesis in the dorsal skinfold chamber in mice.

The host defense peptide human cathelicicin LL37 was tested for in vitro antimicrobial activity in a bilayer radial diffusion assay. For in vivo testing, 4 different concentrations of LL37 or carrier control were instilled into a biopolymer, then inserted into the dorsal skinfold chamber in Balb/c mice. Standard microcirculatory parameters were assessed over 24 days' follow-up.

LL37 showed broad-spectrum antimicrobial activity against gram-positive and -negative bacteria. The LL37 treatment of the biopolymer accelerated the onset of neovascularization by 6 days compared with the carrier control (P < 0.01).

This study demonstrated that LL37 has antimicrobial activity and is important for early support of neoangiogenesis in biopolymers. The multifunctional human host defense peptide LL37 has potential as an adjunct for tissue engineering.