骨髓间充质干细胞-脱细胞膀胱基质-聚丙烯复合网片的生物相容性和力学性能研究

Biocompatibility and mechanical properties of bone mesenchymal stem cells-urinary bladder matrix-polypropylene composite mesh

目的观察骨髓间充质干细胞(bone mesenchymal stemcells,BMSCs)-猪脱细胞膀胱基质(urinary bladder matrix,UBM)-聚丙烯网片(polypropylene mesh,PM)植入大鼠体内的生物相容性与力学性能,探讨其作为替代材料用于修复和重建盆底组织的可行性。方法将SD大鼠分为BMSCs-UBM-PM组、UBM-PM组、PM组、假手术组,分别将材料植于大鼠皮下腹直肌表面。第1、2、4、6周取网片及局部组织,HE染色观察组织病理学变化,免疫荧光观察BMSCs-UBM-PM组中BMSCs存活及分化情况,对第6周取材进行力学性能测试。结果 BMSCs-UBM-PM组炎症细胞浸润少且新生血管较多。免疫荧光示BMSCs可在体内至少存活6周,部分可分化为平滑肌细胞。力学测试:BMSCs-UBM-PM组最大负荷为(0.31±0.08)kN,最大张力位移化为(0.62±0.19)mm/mm,杨氏模数为(43.36±11.83)MPa,均显著高于其他组测试结果(P<0.05)。结论 BMSCs-UBM-聚丙烯复合网片植入大鼠体内后有良好的生物相容性,引起的炎症反应弱,BMSCs诱导分化为平滑肌细胞后可增加复合网片的抗张力强度,因此该复合网片可作为修复和重建盆底组织的候选替代材料。

Objective To observe the biocompatibility and mechanical properties of composite polypropylene mesh （PM） in rats, which was obtained by inoculating urinary bladder matrix （UBM） with bone mesenchymal stem cells （BMSCs）, and to discuss its application as prosthetic material in repair and reconstruc- tion of the pelvic floor tissue. Methods Sprague-Dawley rats were divided into BMSCs-UBM-PM group, UBM-PM group, PM group, and sham-operation group. All the materials were implanted on the abdominal rectus muscle of rats separately. The composite meshes and surrounding tissues were harvested in the 1 st, 2nd, 4th and 6th week after implantation. The histopathological changes were observed by HE staining. The survival and differentiation of BMSCs in BMSCs-UBM-PM group were observed by immunofluorescence staining. Six weeks after implantation, the materials were subjected to a mechanical property test. Results HE staining showed that infiltration of inflammatory cells was more sparse and the new blood vessels were more abundant in BMSCs-UBM-PM group. Immunofluorescence staining vivo and could partly differentiate into smooth muscle showed that BMSCs could survive for at least 6 weeks in cells. In the 6th week, the composite mesh of BMSCs- UBM-PM group showed the maximum load of 0. 31±0.08 kN, maximum tension displacement ratio of 0.62 ± 0.19 mm/mm, and Young＇ s modulus of 43.36 ± 11.83 MPa, which were significantly higher than those of oth- er groups （ P 〈 0. 05 ）. Conclusion BMSCs-UBM-PM exhibits excellent biocompatibility after implantation and causes relatively weaker inflammatory response. BMSCs can be induced to differentiate to smooth muscle cells, thus providing higher tensile strength to the composite mesh that can be used as candidate material for repair and reconstruction of pelvic tissue.