Investigation of the production, purification and binding ability of anti-FGF7 sdAb D47 antibody identified by phage display technique

Abstract

Introduction: Fibroblast growth factor 7 (FGF7) is a member of the fibroblast growth factor (FGF) family. FGF family members are involved in a variety of biological processes, including embryonic development, cell growth, morphogenesis, tissue repair and tumor growth. Therefore, inhibition of FGF7 can be an effective treatment for such pathological states. Aims: In this study, we aimed to investigate the production, purification and binding ability of single domain anti-FGF7 antibody (i.e., D47) identified by phage display technique against FGF7. Material and Methods: The D47 sdAb antibody was cloned into pET28a expression vector. The constructed vector was transformed into E.coli Bl21 plysS and the protein of interest was expressed and subsequently purified using Ni-Sepharose affinity column. The produced sdAb antibody was analyzed by SDS-PAGE and western blotting techniques. To assess the binding ability of the produced sdAb antibody to FGF7, ELISA experiment was performed. Results: The D47 sdAb antibody was produced in bacterial expression system. The protein band at about 17 kDa on SDS-PAGE was attributed to sdAb of interest. The production of sdAb antibody was confirmed by using western blotting technique. In ELISA experiment, the produced sdAb could bind to FGF7 with Kd value of 0.26 μM. Conclusion: In the current work, anti-FGF7 sdAb D47 antibody was expressed in a prokaryotic system and the affinity of the purified protein to FGF7 was elucidated. The findings in the current study can be valuable in designing and developing new FGF7 inhibitors . . . . . . . . . . . . . . . . . .