Generation and functional characterization of a single-chain variable fragment (scFv) of the anti-FGF2 3F12E7 monoclonal antibody

Sci Rep. 2021 Jan 14;11(1):1432. doi: 10.1038/s41598-020-80746-8.

Abstract

Single-chain variable fragments (scFvs) are small-sized artificial constructs composed of the immunoglobulin heavy and light chain variable regions connected by a peptide linker. We have previously described an anti-fibroblast growth factor 2 (FGF2) immunoglobulin G (IgG) monoclonal antibody (mAb), named 3F12E7, with notable antitumor potential revealed by preclinical assays. FGF2 is a known angiogenesis-associated molecule implicated in tumor progression. In this report, we describe a recombinant scFv format for the 3F12E7 mAb. The results demonstrate that the generated 3F12E7 scFv, although prone to aggregation, comprises an active anti-FGF2 product that contains monomers and small oligomers. Functionally, the 3F12E7 scFv preparations specifically recognize FGF2 and inhibit tumor growth similar to the corresponding full-length IgG counterpart in an experimental model. In silico molecular analysis provided insights into the aggregation propensity and the antigen-recognition by scFv units. Antigen-binding determinants were predicted outside the most aggregation-prone hotspots. Overall, our experimental and prediction dataset describes an scFv scaffold for the 3F12E7 mAb and also provides insights to further engineer non-aggregated anti-FGF2 scFv-based tools for therapeutic and research purposes.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Angiogenesis Inhibitors / chemistry*
  • Antineoplastic Agents, Immunological / chemistry*
  • Fibroblast Growth Factor 2 / chemistry*
  • Humans
  • Neoplasm Proteins / chemistry*
  • Single-Chain Antibodies* / chemistry
  • Single-Chain Antibodies* / genetics

Substances

  • Angiogenesis Inhibitors
  • Antineoplastic Agents, Immunological
  • Neoplasm Proteins
  • Single-Chain Antibodies
  • Fibroblast Growth Factor 2