人CD154-GST融合蛋白基因在大肠杆菌中的表达

Cloning of hCD154 gene from human activated peripheral blood mononuclear cell and expression of hCD154-GST fusion protein in prokaryote

目的 :为制备重组人CD15 4-谷胱甘肽巯基转移酶 (GST)融合蛋白 (hCD15 4-GST) ,用于人CD15 4单克隆抗体研制。方法 :根据人CD15 4基因序列设计合成特异性引物 ,RT -PCR扩增人CD15 4基因 ,并插入融合蛋白原核表达载体pGEX - 4T - 1中 ,得到重组表达质粒pGEX - 4T - 1/CD15 4;用此重组质粒转化大肠杆菌BL2 1细胞 ,转化菌落经BamHⅠ、EcoRⅠ酶切鉴定。IPTG诱导大肠杆菌表达人CD15 4蛋白 ,SDS -PAGE电泳鉴定表达产物。结果 :从人外周血淋巴细胞扩增出 82 0bp的hCD15 4cDNA ;将其克隆至pGEX - 4T - 1质粒中 ,经双酶切鉴定及DNA序列分析证实含有目的基因 ;IPTG诱导后的大肠杆菌经SDS -PAGE电泳鉴定出现明显的 5 5kD蛋白带。结论 :成功构建了人CD15 4-GST原核表达质粒 ,并在大肠杆菌中表达出人CD15 4-GST融合蛋白 ,为人CD15

AIM:To express recombinant hCD154-GST fusion protein, to prepare anti-hCD154 monoclonal antibody, and to investigate the effect of anti-hCD154 monoclonal antibody on graft rejection. METHODS AND RESULTS: Total RNA was prepared from human peripheral blood mononuclear cell (PBMC) activated with 10ng/mL PMA and 1 μg/mL PHA for 8h, the total RNA was reversetranscribed to cDNA. The entire coding region and a part of the 3'non-coding regions were amplified by PCR using a pair of primers designed and synthesized according to the sequence of human CD154 gene from gene bank. The amplified product, a 820bp DNA fragment was cloned into pGEX-4T-1 plasmid expressing glutathione S-transferase(GST). The cloned insert was identified by double digestion of the cloned pGEX-4T-1 plasmid with retriction enzymes BamHⅠand EcoRⅠ.The fusion protein expression plasmid of PGEX-4T-1/hCD154 was constructed, then transformed to E coli BL21. The human CD154-GST fusion protein expression was induced by IPTG in BL21. The expression of recombinant 26kD GST and 55kD human CD154-GST fusion protein were confirmed by SDS-PAGE. CONCLUSION: We have express the recombinant human CD154-GST fusion protein. The expressed hCD154-GST fusion protein will be used to prepare anti-hCD154 monoclonal antibody, to investigate the role of anti-CD154 monoclonal antibody on graft rejection.