Xenogeneic bone has good biological activity, but eliminating immunogenicity, while retaining osteogenic abilities, is a challenge. By combining xenogeneic bone with poly amino acid (PAA) that has an amide bond structure, a new type of composite conforming to bionics and low immunogenicity may be obtained. In this study, according to the principles of component bionics, three composites of delipidized cancellous bone powder (DCBP) and PAA were designed and obtained by an in situ polycondensation method, an extrusion molding (EM) method, and a solution-blend method. The three composites were all macroscopically uniform, non-cytotoxic, and demonstrated low immunogenicity by effective removal of residual antigens during preparation. Compared with PAA, mouse bone marrow mesenchymal stem cells (BMSCs) on the surfaces of three composites showed different cellular morphologies. The effects of different preparation methods and cellular morphology on cellular differentiation were confirmed by alkaline phosphatase activity, calcium nodule formation and the expression levels of osteogenic differentiation-related genes (bone morphogenetic protein 2, runt-related transcription factor 2, osteopontin and osteocalcin). Among these composites, DCBP/PAA EM showed best cell proliferation and osteogenic differentiation in vitro, and possessed greater bone formation than PAA in a rabbit femoral condyle study. This study may provide a new method for preparing bioactive bone repair materials with low immunogenicity and superior ability to stimulate differentiation of BMSCs in vitro and osteogenesis in vivo. DCBP/PAA EM might be a promising bone repair material for bone defect treatment.

异种骨具有良好的生物活性，但在保持成骨能力的同时消除免疫原性是一个挑战。通过将异种骨与具有酰胺键结构的聚氨基酸（PAA）结合，可以获得一种符合仿生学且免疫原性低的新型复合材料。本研究根据组分仿生学原理，原位设计并获得了三种脱脂松质骨粉（DCBP）和PAA的复合材料。缩聚法、挤出成型(EM)法和溶液共混法。这三种复合物在宏观上都是均匀的、无细胞毒性的，并且通过在制备过程中有效去除残留抗原而表现出低免疫原性。与 PAA 相比，三种复合材料表面的小鼠骨髓间充质干细胞 (BMSCs) 表现出不同的细胞形态。不同制备方法和细胞形态对细胞分化的影响通过碱性磷酸酶活性、钙结节形成和成骨分化相关基因（骨形态发生蛋白 2、runt 相关转录因子 2、骨桥蛋白和骨钙素）的表达水平得到证实。在这些复合材料中，DCBP/PAA EM 表现出最好的细胞增殖和成骨分化在体外，并且在兔股骨髁研究中具有比 PAA 更大的骨形成。该研究为制备具有低免疫原性和优越的体外刺激BMSCs分化和体内成骨能力的生物活性骨修复材料提供了一种新的方法。DCBP/PAA EM 可能是一种用于骨缺损治疗的有前途的骨修复材料。