Cell-free adipose extract inhibits hypertrophic scar formation through collagen remodeling and antiangiogenesis.

Objective: Hypertrophic scars (HS) are a fibrotic proliferative disorder that results from an abnormal wound healing process, presenting significant challenges for clinical intervention. The primary characteristics of HS include excessive collagen deposition and angiogenesis. In recent years, the study of mesenchymal stem cells (MSCs) and their derived exosomes has emerged as a prominent area of research within the academic community. However, the therapeutic application of MSCs is impeded by several challenges, including immune rejection, sourcing limitations, ethical dilemmas, and difficulties related to the scalability of exosome production. Cell-free adipose extract (CEFAE), a novel bioproduct derived from adipose tissue, is rich in various active protein factors that are essential for MSCs and their exosomes. CEFAE presents several advantages, including low immunogenicity, non-tumorigenicity, and a high degree of clinical safety. However, the application of CEFAE in the prevention and treatment of scar formation has not been adequately validated through experimental studies.

Methods: This research established a rabbit ear scar model, establishing a control group, a low-concentration CEFAE group (L-CEFAE), and a high-concentration CEFAE group (H-CEFAE) to evaluate wound treatment. Observations of scar changes were conducted at 14 and 28 days post-treatment, supplemented by histological and immunohistochemical analyses.

Results: Histological analysis revealed that the H-CEFAE group achieved optimal outcomes, with the lowest collagen deposition, thinnest epidermal/dermal thickness, and the most orderly collagen alignment. Furthermore, the formation of new blood vessels in the H-CEFAE group showed a significant reduction over time, resulting in decreased blood supply, which is beneficial for suppressing scar tissue development. Quantification of COL I, COL III, and vascular endothelial growth factor also supports these results.

Conclusion: The findings indicated that high-concentration CEFAE has a beneficial preventive and therapeutic effect on scar proliferation. Furthermore, the study explored the potential mechanisms by which CEFAE inhibits scar proliferation, thereby providing novel therapeutic strategies for the prevention and management of clinical scars.