Characterisation of monoclonal antibody against aflatoxin B1 produced in hybridoma 2C12 and its single-chain variable fragment expressed in recombinant Escherichia coli

An anti-aflatoxin B-1 monoclonal antibody (anti-AFB(1) mAb) from the hybridoma 2C12 was established and its inhibition concentration fifty (IC50) for AFB(1) and relative cross-reactivities (CRs) to other mycotoxins were estimated to be 8 ng/mL and less than 4% compared with AFB, by a competitive direct enzyme-linked immunosorbent assay. For production of anti-AFB(1) single-chain variable fragment (anti-AFB(1) scFv) in recombinant Escherichia coli, its scFv-coding genes were cloned from the hybridoma 2C12. The anti-AFB(1), scEv formed inclusion bodies in the cytoplasm of E. coli required in vitro refolding process and hence recovered to retain binding activity successfully. Surface plasmon resonance analysis resulted that anti-AFB(1) scEv possessed 1.16 x 10(-7) M of equilibrium dissociation constant (K-D), which was about 17 times higher than the parental anti-AFB(1) mAb of 6.95 x 10(-9) M. (C) 2010 Elsevier Ltd. All rights reserved.