Caprine amniotic membrane as a bioactive scaffold for cutaneous wound repair in rabbits

Restoring functional skin architecture following injury remains a central challenge in regenerative medicine, as adult wound healing typically culminates in fibrotic scarring rather than true tissue regeneration. The amniotic membrane (AM) harbors well-documented anti-inflammatory, anti-fibrotic, and pro-regenerative properties, with established clinical utility in human ocular surface repair. Nevertheless, its translational potential in veterinary cutaneous regeneration and the relative contributions of intact AM scaffolds (fresh as well as cryopreserved) versus AM-derived mesenchymal stem cells (MSCs) and their secretome remain insufficiently characterized.

We conducted a systematic comparative evaluation of multiple AM-derived therapeutic modalities in a rabbit full-thickness cutaneous wound model. Fresh AM, cryopreserved amniotic membrane (cryo AM), cAM-derived MSCs (cAM-MSCs), and MSC-conditioned medium (CM) were assessed for wound healing efficacy. cAM-MSCs were characterized per International Society for Cell & Gene Therapy (ISCT) criteria, encompassing plastic adherence, trilineage differentiation capacity, and immunophenotypic profiling. Ultrastructural morphology was examined by scanning electron microscopy (SEM), and global proteomic profiling was conducted via liquid chromatography-mass spectrometry (LC-MS).

Proteomic analysis identified significant enrichment of proteins involved in extracellular matrix (ECM) remodeling, angiogenesis, and immunomodulatory signaling. In a standardized 2 × 2 cm² full-thickness dorsal wound model in New Zealand White rabbits, both fresh AM and cryo AM markedly accelerated wound closure over 28 days relative to cAM-MSC and CM monotherapies. Histological assessment confirmed superior re-epithelialization, organized collagen deposition, improved dermal architecture, and reduced fibrotic scar formation in AM scaffold-treated groups.

Intact AM scaffolds both fresh and cryopreserved outperform cell-based and secretome-based monotherapies in promoting cutaneous wound repair, positioning placenta-derived biological matrices as scalable, clinically translatable biomaterials for regenerative medicine application.