The Connexin 43 Carboxyl Terminal Mimetic Peptide alphaCT1 Prompts Differentiation of a Collagen Scar Matrix Resembling Unwounded Skin

• Published in: bioRxiv
• Main Authors: Montgomery, Jade, Richardson, William J, Rhett, J Matthew, Bustos, Francis, Degen, Katherine, Ghatnekar, Gautam, Grek, Christina L, Marsh, Spencer, Jourdan, L Jane, Holmes, Jeffrey W, Gourdie, Robert G
• Format: Paper
• Language: English
• Published: Cold Spring Harbor Cold Spring Harbor Laboratory Press 07.07.2020
• Subjects: Animal models; Clinical trials; Collagen; Computer applications; Connexin 43; Fibroblasts; Hairless; Peptides; R&D; Research & development; Skin; Surgery; Wounding
• ISSN: 2692-8205; 2692-8205
• DOI: 10.1101/2020.07.07.191742

Phase II clinical trials have reported that acute treatment of surgical skin wounds with the therapeutic peptide alphaCT1 improves cutaneous scar appearance by 47% 9-months post-surgery - though mode-of-action remains unknown. Scar matrix structure in biopsies 2 to 6 weeks post-wounding treated topically with alphaCT1 or control treatments from human subjects, Sprague-Dawley rats, and IAF hairless guinea pigs were compared. The sole effect on scar structure was that alphaCT1-treated scars had less alignment of collagen fibers relative to control wounds, a state that resembles unwounded skin. This more random alignment was recapitulated in both animal models, together with transient increases in collagen density, although the guinea pig was found to more closely replicate the pattern of response to alphaCT1 in human scars, compared to rat. Fibroblasts treated with alphaCT1 in vitro showed decreased directionality and an agent-based computational model parameterized with fibroblast motility data predicted collagen alignments in simulated scars consistent with that observed experimentally in human and the animal models. In conclusion, alphaCT1 prompts decreased directionality of fibroblast movement and the generation of a 3D collagen matrix post-wounding that is similar to unwounded skin - changes that correlate with long-term improvement in scar appearance. Competing Interest Statement GSG is CEO and President of FirstString Research Inc. CLG is Senior Director of Research and Development at FirstString Research Inc. RGG is a non-remunerated member of the Scientific Advisory Board of FirstString Research, which licensed α carboxyl terminus 1 peptide. GSG, RGG, LJJ, and CLG have ownership interests in FirstString Research Inc. The remaining authors have no disclosures to report.