PBAD表达系统对抗-HBs Fab抗体表达的影响

目的研究PBADP替换Plac的原核表达系统对重组抗-HBs Fabs的表达效率、产量及其抗体活性的影响。方法通过Western blot、抗体不同稀释度的Dot blot和抗原特异性结合实验，对两种表达系统进行比较。结果在PBAD控制下表达的抗．HBs Fabs与Plac控制下的相比，Western blot显示两种表达系统都能完整表达抗-HBs Fab抗体，Mr为50000。PBAD表达系统表达的抗-HBs Fabs多以可溶形式存在于周质腔中，而Plac表达系统表达的抗-HBs Fabs更多的释放入培养上清液。抗体不同稀释度的Dot blot结果显示pBAD-抗HBs Fab表达系统表达的抗体效价较pComb3-抗HBs Fad高，乙型肝炎表面抗原特异性结合实验证实两种表达系统表达的抗体的抗原结合活性无明显差别。结论PBAD表达系统明显提高了抗-HBs Fab的表达量并保持了原抗体活性。

Effects of PBAD expression system on anti-HBs Fab expression

Objective To investigate the effects of P BAD, as an alternative system to P lac, on the expression efficiency, expression production, and antigen-binding activity of the recombinant anti-HBs Fab. Methods The two prokaryotic expression systems were compared by Western blotting and dot blotting with different dilution activities. Results The human recombinant anti HBs Fabs were completely expressed by the two prokaryotic expression systems. The molecular weight of Fab was about M r 50 000 and the protein was confirmed to be anti-HBs Fab by Western blotting. The anti-HBs Fabs expressed by P BAD were localized to the soluble periplasmic fraction whereas P lac expressed anti-HBs Fabs were released into the culture supernatant. Dot blotting with different dilution of Fab indicateed that the title of Fab from P BAD expression system was higher than that from pComb3. No significant difference of anti-HBs Fab binding capacity between the two systems was found. Conclusion P BAD expression system elevates the Fab production, and maintains the original antibody activity.