基于M2巨噬细胞干预的脂肪干细胞抑制增生性瘢痕研究

ADSCs can inhibit fibrosis by inhibiting the p38/MAPK signaling pathway. However, its lack of effective regulation of early inflammatory response limits its effect on the treatment of hypertrophic scar (HS). Studies have shown that M2 macrophages have anti-inflammatory effect, but it can promote the formation of fibrosis in the tissue remodeling stage of wound healing. Our previous study have shown that inhibiting early inflammatory response can help to reduce HS formation; Hydrogel scaffold assisted ADSCs injection could help to improve the long-term survival rate of ADSCs, thus enhance its anti-fibrosis and tissue repairing function.On this basis, we proposed to reduce inflammation by regulating of M2 macrophages, improving the survival rate of ADSCs, depleting M2 macrophage and inhibiting fibrosis through implantation of ADSCs-hydrogel-clodronate liposomes, thus to achieve a comprehensive anti-HS therapy. To test this hypothesis, this project will use a rabbit ear HS model to explore the outcome of inflammation intervened by regulation of M2 macrophages, and to clarify the mechanism and treatment effects on HS through ADSCs injection combined with regulation of M2 macrophages in different phases of wound healing. The cellular, gross level, tissue level and molecular biology level changes in HS in the rabbit ear model would be studied.

ADSCs可通过抑制p38/MAPK信号通路而抑制纤维化，然因缺乏对早期炎症反应的有效调控，限制了其治疗增生性瘢痕（HS）的效果。研究表明M2巨噬细胞具有抗炎症反应作用，然其在组织增生重塑阶段可促进纤维化形成从而促进HS形成。我们前期研究表明早期减轻炎症反应和后期抗纤维化治疗均可减轻HS形成，利用水凝胶支架辅助ADSCs注射治疗可提高ADSCs的保存率、增强其抗纤维化和促修复功能。在此基础上，我们拟通过调控伤口早期的M2巨噬细胞数量以增强抗炎症反应、在组织增生重塑期灭活M2巨噬细胞实现抗纤维化，并联合植入可通过提高ADSCs的存活率的ADSCs-氯磷酸二钠脂质体-水凝胶支架，实现联合抗HS治疗。为验证这一假说，本课题将利用兔耳HS模型，通过细胞、大体、组织和分子生物学等多水平探索M2巨噬细胞的调控与炎症反应转归、揭示阶段性M2巨噬细胞调控与ADSCs联合治疗对HS的影响，并阐明其作用机制。

增生性瘢痕是伤口愈合过程中的常见不良后果，严重影响患者的外观和皮肤屏障功能，为患者带来了极大的经济负担和精神压力。针对这一疾病，目前尚无有效的预防和治疗策略。积极寻求促伤口愈合抑增生性瘢痕形成的促皮肤再生措施具有重大意义。本课题在前期研究的基础上，进一步明确了脂肪干细胞分泌物和IL-10诱导M2c巨噬细胞促伤口愈合抑瘢痕形成的重要作用，并分别将脂肪干细胞条件培养基和IL-10负载于电纺丝生物材料中，制备了具有缓释性能的促皮肤再生新型伤口敷料。此外，本研究分别开展体外细胞实验和小鼠皮肤全层切除体内实验，比较分析新型伤口敷料对collagen I，collagen III，α-SMA，VEGF等蛋白表达的影响，进一步证实了脂肪干细胞和IL-10诱导M2c巨噬细胞分泌的细胞因子强大的促伤口愈合抑制纤维化的作用。本研究开发了可有效抑制瘢痕形成促进皮肤愈合的新型伤口敷料。为临床上新的促皮肤组织无瘢痕愈合的再生策略。已发表或录用论文6篇。