Department of Biotechnology, Tokyo University of Agriculture and Technology, Koganei, Tokyo 184-8588, Japan.
Acta Biomater. 2011 Mar;7(3):1192-201. doi: 10.1016/j.actbio.2010.10.032. Epub 2010 Nov 3.
Genetically modified silk fibroin containing a poly-glutamic acid site, [(AGSGAG)4E8AS]4, for mineralization was produced as fibers by transgenic silkworms through systematic transformation of the silkworms. The Ca binding activity and mineralization of the transgenic silk fibroin were examined in vitro, showing that this transgenic silk fibroin had relatively high Ca binding activity compared with native silk fibroin. Porous silk scaffolds were prepared with the transgenic and native silk fibroins. Healing of femoral epicondyle defects in rabbit femurs treated with the scaffolds was examined by observing changes in images of the defects using micro-computed tomography. Earlier mineralization and bone formation were observed with scaffolds of transgenic silk fibroin compared with those of native silk fibroin. Thus, this study shows the feasibility of using genetically modified silk fibroin from transgenic silkworms as a mineralization-accelerating material for bone repair.
通过对家蚕进行系统转化，生产出一种含有聚谷氨酸位点 [(AGSGAG)4E8AS]4 的转基因丝纤维，用作矿化的丝纤维。在体外检测了转基因丝纤维的钙结合活性和矿化作用，结果表明，与天然丝纤维相比，这种转基因丝纤维具有相对较高的钙结合活性。用转基因丝纤维和天然丝纤维制备多孔丝支架。通过观察微计算机断层扫描图像中缺陷的变化，研究了用支架治疗兔股骨髁部缺损的愈合情况。与天然丝纤维支架相比，用转基因丝纤维支架观察到更早的矿化和骨形成。因此，本研究表明，使用转基因家蚕的转基因丝纤维作为骨修复的加速矿化材料是可行的。
