Abstract:

Since 2011，the new outbreak of pseudorabies virus（PRV）variant strain in China has greatly increased the detection workload of the virus. At present， the widely use of blocking ELISA kits has raised the greater demand for monclonal antibodies. However， hybridoma cells often lose antibody secretion capacity during passages. This study aimed to prepare single-chain fragment variable with good binding activity on the basis of monoclonal antibody and achieve large-scale production via prokaryotic expression system， providing a foundation for novel detection methods. The prokaryotically expressed PRV gE protein was used to immunize mice. Positive hybridoma cells stably secreting anti-PRV gE mabs were obtained through cell fusion and screening. The cDNA of the positive hybridoma cells was used as a template to amplify the variable region sequence of antibody，and the scFv gene was constructed by linking the variable regions of heavy and light chain with a Linker peptide. The scFv gene was cloned into pET-28a plasmid for prokaryotic expression to produce the recombinant antibody. A monoclonal antibody 7B7 specific to the gE protein of PRV was successfully screened. Using the cDNA of 7B7 hybridoma cells as a template，a single chain fragment variable capable of specifically reacting with PRV gE was successfully prepared which can be expressed by prokaryotic expression system， providing a basis for the development of new detection methods for PRV.

Key words: pseudorabies virus, gE protein, single chain fragment variable