A combinatorial therapeutic platform based on graphene-collagen cryogel and apoptotic vesicles for modulating...

Graphene-based collagen hydrogels have demonstrated anti-fibrotic potential in various diseases; however, their therapeutic efficacy in hypertrophic scars (HS) remains largely unexplored. Adipose stem cells (ASCs) and their extracellular vesicles have been shown to regulate HS progression, yet the role of ASCs derived apoptotic vesicles (ASCs-ApoVs) has not been fully investigated. In this study, we developed graphene-incorporated type I collagen cryogel (G-GEL(C)) and collected ASCs-ApoVs. We evaluated their individual and combined capacity to regulate HS and explored the potential of G-GEL(C) as a delivery system for ASCs-ApoVs. G-GEL(C) significantly inhibited fibrosis in HS derived fibroblasts (HS-fibroblasts), as evidenced by the downregulation of COL1A1 (p < 0.001 for both protein and mRNA), α-SMA (p < 0.001 for protein; p < 0.0001 for mRNA), and Vimentin (p < 0.05 for protein; p < 0.0001 for mRNA). Additionally, G-GEL(C) suppressed cell proliferation (p < 0.0001) and lateral migration (p < 0.001). Treatment with ASCs-ApoVs also reduced COL1A1 (p < 0.01 for protein; p < 0.0001 for mRNA) and α-SMA (p < 0.05 for both protein and mRNA), while Vimentin transcription was also downregulated (p < 0.001). G-GEL(C), characterized by high porosity and selective adsorption capacity for ASCs-ApoVs, enabled efficient loading and delivery of these vesicles. In vivo, G-GEL(C) loaded with ASCs-ApoVs decreased the scar elevation index (SEI) (p < 0.05), reduced α-SMA expression (p < 0.0001), locally increased 8-OHdG levels and raised the proportion of M2 macrophages, indicating effective regulation of HS. ASCs-ApoVs exhibit anti-fibrotic effects in HS. G-GEL(C) functions both as a direct modulator of HS-fibroblast phenotypes and as an efficient carrier for apoptotic vesicles. Collectively, they form a potent combinatorial system that significantly attenuates hypertrophic scar.