Bone Induction by Human Bone Morphogenetic Protein Expressing Adenoviral Vector

灵长类动物需要大量的骨形态发生蛋白(BMP)来获得骨诱导，在该蛋白的条件下使用BMP才能稳定骨诱导。这是临床应用的一大难题。由于腺病毒对灵长类动物的感染效率特别高，利用腺病毒载体的骨形态发生蛋白基因转移方法有可能解决这一问题。用活载体体外感染C2C12细胞。证实了C2C12基因的有效转移和BMP-2在感染细胞中的表达。通过该载体转染骨形成蛋白-2基因的C2C12细胞表现出细胞内碱性磷酸酶的积聚，并向培养液中产生和分泌骨钙素，表明在体外将骨形成蛋白-2基因转移到这些细胞中已引起成肌细胞向Osteo…转化。更具爆发力的血统。在体内检测病毒载体转导BMP-2基因的效果。当病毒载体注射免疫抑制时，可以在肌肉中观察到骨诱导。我们还评估了病毒载体在免疫活性和免疫抑制大鼠体内诱导成骨的时间进程。体内骨形成仅见于免疫抑制的大鼠，而感染病毒载体的细胞在注射后不久即被宿主免疫系统清除。因此，我们使用生物材料(阿特洛肽胶原)来评估病毒载体的成骨作用，以掩盖免疫活性大鼠的免疫反应或局部应用免疫抑制剂。我们的结果表明，表达BMP-2的腺病毒载体可以在瞬时免疫抑制、局部应用免疫抑制剂或有效掩盖宿主免疫反应的情况下进行基因治疗，可能有助于骨重建。较少

Large quantity of bone morphogenetic protein (BMP) is required with primates to get the bone induction for which to become stable when BMP is used under the condition of the protein. This is a big problem for clinical application. There is a possibility to solve this problem by using the BMP gene transfer method with an adenoviral vector because the infection efficiency of the adenovirus is especially high with primates.We constructed a human bone morphogenetic protein-2 (BMP-2)-expressing adenoviral vector. C2C12 cells were infected in vitro with the vital vector. An efficient gene transfer to the C2C12 and BMP-2 expression in the cells infected with the viral vector were confirmed. C2C12 cells transfected with the BMP-2 gene by the vector showed intracellular accumulation alkaline phosphatase, and also produced and secreted osteocalcim into the culture medium, demonstrating that in vitro transfer of the BMP-2 gene to these cells had caused the transformation of myoblasts to the osteo … More blast lineage. Then we examined the effectiveness of BMP-2 gene transfer by the viral vector in vivo. Osteoinduction was seen in muscle when the viral vector was injected immunosuppression. We also evaluated the time course of osteoinduction by the viral vector in immunocompetent and immunosuppressed rats. In vivo bone formation at 14 and 21 days after injection was only seen in the immunosuppressed rats, while most of the cells infected with the viral vector were eliminated by the host immune system soon after injection in the immunocompetent rats. Therefore, we evaluated osteoinduction by the viral vector using biomaterial (atelopeptide collagen) to mask the immune response or local application of immunosuppressant in immunocompetent rats.Our results suggested that gene therapy with the BMP-2-expressing adenoviral vector could be performed under transient immunosuppression, with local application of immunosuppressant, or with effective masking of the host immune response and may be useful for bone reconstruction. Less