目的完全去除猪主动脉瓣的细胞,制备成去细胞猪瓣支架。方法采用胰酶+TritonX-100制备去细胞猪瓣支架,标本进行形态、组织结构观察,并进行DNA含量和力学强度测定。以新鲜猪瓣为对照将去细胞瓣叶家兔皮下埋藏4周后分别取材,光镜进行检查。结果采用胰酶+TritonX-100法能完全脱除猪主动脉瓣膜细胞,去细胞后瓣膜可溶性蛋白明显丢失[(0.24±0.04)%vs(0.48±0.12)%],瓣叶含水量增加[(92.2±1.5)%vs(89.2±1.6)%](P〈0.01),但去细胞猪瓣仍保持了良好纤维支架结构,热皱缩温度[(67.9±1.0)℃vs(68.8±0.8)℃]和断裂强度[(489.3±19.0)g/mm^2 vs(540.7±19.5)g/mm^2]未见显著变化(P〉0.01)。埋藏于兔皮下的去细胞猪主动脉瓣有轻微组织反应,可见少量中性粒细胞、淋巴细胞和浆细胞浸润,炎性反应明显轻于新鲜猪瓣组。结论成功制备去细胞猪瓣支架,并保持良好的纤维支架结构和机械强度,抗原性轻微。
Objective To prepare a porcine aortic valve (PAV) free of the cellular components. Methods The cellular components of porcine PAV were completely removed using trypsin and Triton X-100, and the acellular PAV was examined microscopically with HE staining with its physical and chemical properties assessed. Transmission electron microscopy was used to observe the integrity of the collagen and elastin and the DNA contents in the PAV was detected to confirm the total removal of the cellular components. With the fresh PAV as the control, small pieces of the acellular PAV were implanted into the subcutaneous tissues of 4 rabbits, and 4 weeks after the implantation, the implants were harvested for microscopic observation. Results The cellular components were effectively removed from the cusps and roots of the PAV by trypsin and TritonX-100, with marked soluble protein loss E(0.24±0.04)% vs (0.48±0.12)% ] and significantly increased water content [(92.2±1.5)% vs (89.2±1.6)% ]. The acellular PAV still maintained good fibrous scaffold structure and the shrinkage temperature and tension at fracture underwent no significantly changes E(67.9±1.0) ℃ vs (68.8±0.8) ℃ and (489.3±19.0) g/mm^2 vs (540.7±19.5) g/mm^2, respectively]. The PAVs implanted in rabbits showed only mild tissue reaction with a few infiltrating neutrophils, lymphocytes and plasmocytes observed 4 weeks later. The accelular PAV caused obviously milder inflammatory reactions than fresh PAV. Conclusion The acellular PAV prepared by treatment with trypsin and Triton X-100 retains good fibrous scaffold Structure and mecfianical strength with low antigenicity.