Selection, affinity maturation, and characterization of a human scFv antibody against CEA protein

Abstract

Background: CEA is a tumor-associated antigen abundantly expressed on several cancer types, including those naturally refractory to chemotherapy. The selection and characterization of human anti-CEA single-chain antibody fragments (scFv) is a first step toward the construction of new anticancer monoclonal antibodies designed for optimal blood clearance and tumor penetration.

Potent inhibition of OKT3-induced T cell proliferation and suppression of CD147 cell surface expression in HeLa cells by scFv-M6-1B9

“…The reasoning behind our scFv format was to preserve the genetic source of the antibody fragment by cloning it into a phagemid vector and utilizing relatively simple production in bacteria. Furthermore, the small molecular size of scFv should provide high tissue penetration efficiency (Kioi et al, 2008;Liu et al, 2008;Stirnemann et al, 2008), and a lack of significant toxicity (Korn et al, 2004;Yang et al, 2007a;Nam et al, 2008) while giving rapid plasma clearance (Mao et al, 1999;Hamilton et al, 2002;Olafsen et al, 2004;Pavoni et al, 2006), which makes such an antibody a potentially suitable candidate for clinical application.…”

Directed Evolution to Low Nanomolar Affinity of a Tumor-Targeting Epidermal Growth Factor Receptor-Binding Affibody Molecule

“…29,34 The small size offers a convenient affinity maturation principle. Unlike complex multistep affinity maturations of antibodies, 21,35 here, a single oligonucleotide could be used to generate the affinity maturation library in one step, in a similar fashion as a previously described affinity maturation of a HER2-binding Affibody molecule. 36 Furthermore, Affibody molecules can easily be site-specifically labeled, either via a cysteine residue introduced upon recombinant expression or through the incorporation of suitable chelators upon peptide synthesis.…”

Antibodies against Venom of the Snake Deinagkistrodon acutus

“…Among various antibody forms, the antigen-binding fragment or singlechain variable fragment (scFv) displayed on the phage is highly suitable and fast for selecting specific antibodies (23)(24)(25). Among the many animals that are adequate as animal models for producing antibodies against immunizing antigens, chickens are the most convenient and rapid host for constructing antibody libraries for selecting specific scFvs against various targets for therapy or diagnosis (24,26,27).…”