[Expression and bioactivity analysis of the fusion protein GFP-V(L) of the neutralizing monoclonal antibody MA18/7 against HBV].

AIM To express the fusion protein of enhanced green fluorescent protein (EGFP) with the light chain variable domain of the neutralizing monoclonal antibody MA18/7 (mAb) against hepatitis B virus in E.coli, and determine its bioactivity. METHODS The EGFP gene was cloned into vector pTO-T7 to construct an expression vector. And then according to ORF gene, MA18/7-V(L) was inserted into the 5' terminal of EGFP gene free of terminal code TAA to construct expression vector of fusion protein. The fusion protein was expressed in E.coli and its bioactivity was detected with ELISA and relative fluorescence intensity. RESULTS The expression vector EGFP-V(L) was constructed. SDS-PAGE analysis showed that expressed fusion protein was mainly in the form of inclusion body. The fusion protein retained the property of EGFP and it could bind to V(H) to form Fv which had binding activity to pre-S1. CONCLUSION The obtained fusion protein had good bioactivity and could be applied to further studies.