Experimental study of microporous acellular dermal matrix and mesenchymal stem cells composite grafttor remodeling the cutaneous defect of nude mice
WAN Li1．LU0 Xu2．xIN Guohua3．LI Anle4．ZENGTaofang5．XIA Weidong2．LI Xiaokun6．LlN Cai2
1．Department ofPathology,the First Affiliated Hospital of Wenzhou Medical College，Wenzhou．325000；2．Department ofBurn．the Ftnl Affiliated Hospital of Wenzhou Medical College．Wenzhou．325000；3．Department ofBurn。the First Affiliated Hospital ofNanchang University,Nanchang，330000；4．ExperimentalAnimal Center,Wenzhou Medical Coltege，Wenzhou，325035；5．Department of Burn．the People's Hospital of Yichum City,Yichun，336000；6．School ofPharmacy,Wenzhou Medical College．
Wenzhou，325035
摘要目的：探讨以激光微孔化脱细胞真皮基质(LPADM)为载体，骨髓间充质干细胞(MSCs)接种复合自体刃厚皮移植重建皮肤功能的可行性。方法：在已制备的LPADM表皮面接种MSCs，构成含有特殊种子细胞的真皮基质材料(MSCs．LPADM)。取健康雄性裸鼠18只，随机分为三组(每组6只)，麻醉后背部深筋膜层以上制作成2．0 cm x 2．0 Cfll的全层皮肤缺损创面，分别移植三种不同真皮基质(MSCs—LPADM、LPADM、MSCs—PADM)，同期复合移植自体刃厚皮片。A组(MSCs—LPADM+刀厚皮片组)：予MSCs微孔化脱细胞真皮基质复合自体刃厚皮移植；B组(LPADM+刃厚皮片组)：予LPADM复合自体刃厚皮移植；C组(MSCs—PADM+刃厚皮片组)：予MSCs未打孔脱细胞真皮基质复合自体刃厚皮移植。观察皮片大体愈合情况，并于术后3、7、14 d切取移植区标本，行大体、组织学及电镜观察。结果：术后3 d组织学观察A、B两组在移植后真皮基质微孔径结构中均可见空腔样血管结构形成，C组真皮基质中未见血管结构形成。术后7 d，A、B两组移植皮片泛红成活，且两组真皮基质微孔径结构中血管结构更加明显，C组移植皮片出现苍白或变暗坏死。术后14 d，组织学观察示A、B两组真皮基质微孔径结构中可见丰富血管形成，复合皮血管化充分且成活良好，c组胶原结构中仅见少量细胞迁入，未见血管形成，皮片完全坏死。透射电镜显示A组新生的无髓神经样结构，在真皮基质的浅层，可见单个皮脂腺样细胞，深层见单个汗腺样细胞，B组、C组均禾见神经样结构的增生及类汗腺细胞、类皮脂腺结构。结论：LPADM复合移植给提前种植的外源性MSCs提供较为理想的增殖分化微环境。对重建移植后皮肤功能提供了一种方法或思路。
Abstract：Objective：To investigate the healing effect and the remodeling practicability of skin function of the composite graft consisting of laser micropore porcine acellular dermal matrix(LPADM)and mesenchymal stem cells(MSCs)on full—thickness skin wounds．Methods：The composite grafts were prepared by seeding the MSCs on the LPADM(MSCs—LPADM)or the normal porcine acellular dermal matrix(MSCs—PADM)．0ne fullthickness wounds(2 cm x 2 cm)were created on each back of l 8 nude mice and were randomly divided into 3groups(n=6)．Then the MSCs—LPADM were transplanted synchronously with the split—thickness autograft on
the wounds(group A)．The mice treated with LPADM(group B)or MSCs—PADM(groups C)were considered as control．The gross wound healing status was examined．Tissue samples were collected at day 3，7 and 14 post—operation for histological examination and transmission electron microscopy(TEM)obeservation．Results：H&E staining showed the appearance of the cavity—like vascular structure in group A and B at day 3 post—operation，but not in group C．At day 7，the grafts of A and B groups survived well and new vessels can be seen evidently in the micropores．However，grafts necrosis occurred in group C with pallor or black tissue．At day 14，all the grafts survived in A and B groups and abundant blood vessels in the micropores of the matrixs were observed as well，while in group C，no blood vessel appeared and all the grafts went through necrosis and exfoliation．Through TEM observation，we found newly generated unmyelinated nerve—like structure in group A with visible sebaceous gland—like cells in the superficial layer and single sebaceous gland—like cells in the deep layer of the demal matrix，which can not be seen in group B and C．Conclusion：The composite graft(MSCs—LPADM)has better healing effect and provides a good microenvironment for the exogenous hMSCs to proliferation and differentiation，thus may have agreat potential for use in wound reconstruction in the future．
