EXPRESSION AND PURIFICATION OF SINGLE-CHAIN ANTI-HBX ANTIBODY IN ESCHERICHIA-COLI

Monoclonal antibodies have been widely used in tumor targeting studies with promising results. However, their clinical application has been limited by heterogeneity and macro-molecular movement of murine antibo dy. In this study, the variable-region (heavy-and light-chain) fragmen ts of anti-HBx monoclonal antibody were enriched by the polymerase cha in reaction. The expression vector, which included a 6x histidine sequ ence in the 3' terminus of the HBx single-chain antibody (sFv) was rec ombined with a linker sequence (KLGGGGFSGA) between the variable regio ns. The expression product from Escherichia coli fused with 6xHis was purified by nickel (Ni2+) nitrilotriacetate chelating resin. The resul ts of enzyme-linked immunosorbent assay and Western blotting showed th at sFv had binding affinity with HBxAg, suggesting that it could becom e a novel targeting carrier in clinical trials.