Xenogeneic bone showed great prospects to treat large bone defects due to its bionic composition and structure, but the immunogenicity limited its wide applications. Previously, we developed a pepsin treating method to eliminate the immunogenicity of xenogeneic bone. In this study, we further investigated the effect of pepsin processing time on the biological and mechanical properties. The results indicated that increased pepsin treating time impaired the mechanical properties of xenogeneic bone. And MC3T3-E1 cells showed enhanced adhesion ability, as well as increased production of alkaline phosphatase and calcium nodulus production on the xenogeneic bone processed by pepsin for 24 hr (P24), as compared with xenogeneic bone processed by pepsin for 30 hr (P30) and 36 hr (P36). In addition, we found no significant inflammatory responses after implanting different xenogeneic bone into the intermuscular site of rats. These results suggested that xenogeneic bone processed by pepsin for 24 hr may be a preferable choice when using the xenogeneic bone as biomaterials for further researches.

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优化胃蛋白酶处理时间以平衡异种骨的力学和生物学特性

异种骨由于其仿生组成和结构在治疗大骨缺损方面显示出广阔的前景，但免疫原性限制了其广泛的应用。此前，我们开发了一种胃蛋白酶处理方法来消除异种骨的免疫原性。在这项研究中，我们进一步研究了胃蛋白酶加工时间对生物和力学性能的影响。结果表明，增加胃蛋白酶处理时间会损害异种骨的力学性能。与胃蛋白酶处理 30 小时 (P30) 的异种骨相比，MC3T3-E1 细胞在胃蛋白酶处理 24 小时 (P24) 的异种骨上显示出增强的粘附能力，以及碱性磷酸酶和钙结节的产生增加和 36 小时 (P36)。此外，我们发现将不同异种骨植入大鼠肌肉间部位后没有明显的炎症反应。这些结果表明，将异种骨作为生物材料进行进一步研究时，经胃蛋白酶处理24小时的异种骨可能是优选的选择。