评估胚胎干细胞来源的免疫与基质调节细胞（IMRC）对创伤性异位骨化（THO）的干预效果及其潜在作用机制。

建立SD大鼠跟腱损伤THO模型，随机分为假手术组、对照组和IMRC治疗组。IMRC治疗组于术后局部注射含1×10⁶ 个IMRC的细胞悬液，每周2次，持续4周。于术后第4、8、12周通过显微计算机断层扫描（Micro-CT）定量分析异位骨体积和骨矿物质密度（BMD）；通过苏木精-伊红染色和马松三色染色评估组织炎症、纤维化及异位骨形成情况；通过免疫组化染色检测α-平滑肌肌动蛋白（α-SMA）和骨钙蛋白（OCN）表达水平；并通过体重监测和脏器病理学检查评估安全性。

与对照组相比，IMRC治疗显著抑制了异位骨形成。Micro-CT显示，术后12周IMRC治疗组异位骨体积[（16.67±0.90） mm³]较对照组[（81.42±2.72） mm³]减少79.5%（P<0.001），BMD也显著降低[（223.78±16.65） mg/cm³比（595.14±30.31） mg/cm³， P<0.001]。组织学分析表明，IMRC治疗组炎症细胞浸润、胶原沉积及纤维化评分均显著下降（均P<0.01），同时α-SMA和OCN表达受到显著抑制（均P<0.01）。所有大鼠体重稳定增长，主要脏器未见病理改变，表明IMRC治疗安全性良好。

IMRC局部注射可通过抑炎-抗纤维化-抑成骨的多重机制，安全有效地抑制THO的发生与发展，是一种具有广阔转化前景的新型细胞治疗策略。

To evaluate the therapeutic effect and potential mechanism of action of embryonic stem cell-derived immunity and matrix regulatory cells （IMRC） on traumatic heterotopic ossification （THO）.

A THO model was established via Achilles tendon injury in SD rats， which were then randomly divided into a sham operation group， a control group， and an IMRC treatment group. The IMRC group received local injections of a suspension containing 1×10⁶ IMRCs twice weekly for 4 weeks post-operation. At 4， 8， and 12 weeks post-surgery， heterotopic bone volume and bone mineral density （BMD） were quantitatively analyzed using micro-computed tomography (Micro-CT). Tissue inflammation， fibrosis， and heterotopic bone formation were assessed via haematoxylin-eosin stain and Masson staining. The protein expression levels of α-smooth muscle actin （α-SMA） and osteocalcin （OCN） were detected by immunohistochemistry. Safety was evaluated by monitoring body weight and examining the pathology of major organs.

Compared to the control group， IMRC treatment significantly inhibited heterotopic bone formation. Micro-CT revealed that at 12 weeks post-operation， the heterotopic bone volume in the IMRC group [（16.67±0.90） mm³] was reduced by 79.5% compared to the control group [（81.42±2.72） mm³] （P<0.001）， and the BMD was also significantly lower [（223.78±16.65） mg/cm³ vs （595.14±30.31） mg/cm³， P<0.001]. Histological analysis showed significant reductions in inflammatory cell infiltration， collagen deposition， and fibrosis scores in the IMRC group （all P<0.01）， alongside markedly suppressed expression of α-SMA and OCN （all P<0.01）. All rats exhibited steady body weight gain， and no pathological changes were observed in the major organs， indicating a favorable safety profile for IMRC treatment.

Local injection of IMRC can safely and effectively inhibit the development and progression of THO through a multi-mechanism approach involving anti-inflammation， anti-fibrosis， and inhibition of osteogenesis， representing a novel cell therapy strategy with broad translational potential.