OPG-HSP65重组蛋白的原核表达及其生物学活性研究

PCR扩增OPG-HSP65基因，构建原核重组表达载体pET-28a－OPG-HSP65，转化大肠杆菌BL21（DE3），经IPTG诱导表达产生包涵体形式的目的蛋白。对重组蛋白进行Western blot检测表明，重组蛋白能与抗His-Tag单克隆抗体及鼠抗人OPG单克隆抗体特异性结合。对重组蛋白进行尿素洗涤纯化，进而透析、复性。经破骨细胞生长抑制实验和抑炎实验表明，重组蛋白能减少破骨细胞生成及减轻迟发型超敏反应小鼠模型炎症反应。

Expression and Biological Characterization of Human Osteoprotegerin Fused with Mycobacteria Heat Shock Protein 65

A fused functional gene of human OPG and Mhsp65 was amplified by PCR, and cloned into the prokaryotic expression vector pET-28a. The BL21 (DE3) strain of E.coli was transformed using the recombinant plasmid pET-28a-OPG-HSP65 and the expected protein was expressed by induction with IPTG. Result of SDS-PAGE indicated that the expected recombinant protein of 23 kDa was expressed with high yield as inclusion body. The fusion protein could be specifically recognized by both the anti-His antibody and anti-human OPG monoclonal antibody in Western blot analysis. The purified and refolded fusion protein could inhibit osteoclast proliferation and bone absorption in vitro. The results of mouse ear swelling assay and expressions of TNF-α, IFN-γ and IL-17 mRNAs detected by real-time quantitative PCR demonstrated that the fusion protein had an anti-inflammation activity. The results suggest that the fusion protein of human OPG and Mhsp65 may act as a potential therapeutics for rheumatoid arthritis.