Production and in vitro refolding of a single-chain antibody specific for human plasma apolipoprotein A-I

• Published in: Journal of biotechnology 2000-02, Vol.77 (2), p.169-178
• Main Authors: Cho, Won-Kyung, Sohn, Uik, Kwak, Ju-Won
• Format: Article
• Language: English
• Subjects: Affinity chromatography; Animals; Antibodies, Monoclonal - biosynthesis; Antibodies, Monoclonal - chemistry; Antibodies, Monoclonal - genetics; Antibody Specificity; Apolipoprotein A-I; Apolipoprotein A-I - immunology; Bioassay; Biological and medical sciences; Biosensors; Biosynthesis; Biotechnology; DNA; Escherichia coli; Escherichia coli - genetics; Fundamental and applied biological sciences. Psychology; Gene Expression; Health. Pharmaceutical industry; Humans; Immunoglobulin Fragments - chemistry; Immunoglobulin Fragments - genetics; Immunoglobulin Variable Region - chemistry; Immunoglobulin Variable Region - genetics; Immunological technics applied to diagnosis; Inclusion body; Industrial applications and implications. Economical aspects; Lipids; Mice; Monoclonal antibodies; Polymerase Chain Reaction; Protein Folding; Purification; Recombinant Proteins - biosynthesis; Recombinant Proteins - chemistry; Recombinant Proteins - immunology; Refolding and renaturation; Single-chain antibody; Solubility
• ISSN: 0168-1656; 1873-4863
• DOI: 10.1016/S0168-1656(99)00200-X

An active form of single-chain antibody (scFv) has been produced in Escherichia coli for murine monoclonal antibody MabA34 (γ1, κ), which is specific for human plasma apolipoprotein (apo) A-I. The complementary DNAs (cDNAs) encoding the variable regions of heavy chain (V H) and light chain (V L) were connected by a (Gly 4Ser) 3 linker using an assembly polymerase chain reaction. The construct (V L-linker-V H) was placed under the control of highly efficient T7 promoter system. The cloned scFv was expressed in E. coli as inclusion bodies. After purification from E. coli lysate using sonication and low speed centrifugation, the inclusion body was solubilized and denatured in the presence of 8 M urea, renatured by dialysis, and scFv was finally purified using antigen-affinity chromatography. The purity and activity of purified scFv were confirmed by sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis (PAGE), Western blotting and enzyme-linked immunosorbent assay (ELISA). The affinity constant was determined by a biosensor method using the BIAcore system. The results showed that the yield of correctly refolded scFv was more than 20 mg l −1 of E. coli flask culture and the specific binding activity to apo A-I was retained with an affinity constant of 6.74×10 −8 M ( K d). A notable thing is that guanidine–HCl as a denaturant induced more multimeric formation in the subsequent refolding procedure for the scFv of MabA34 and thus, it was not suitable as urea was. This fact is uncommon for what is generally known for the denaturation and refolding of recombinant antibodies.