Construction and screening of anti-swine influenza virus phage display scFv library

The single chain variable fragment(scFv) antibody library specific to swine influenza virus(SIV) was constructed in this study.The BALB/c mice were immunized with SIV,and the total RNA was extracted from spleen cells and reverse transcribed into cDNA.Using cDNA as template,the variable region genes(VH and VL) from heavy chain and light chain were amplified by PCR,respectively.Then they were linked by a DNA linker(G1y4 Ser) to VH-linker-VL sequence,thus forming scFv by SOE(splicing by overlap extension) PCR.The scFv gene was digested by restriction enzyme SfiⅠand NotⅠ,then ligated into the vector of pCANTAB5E.The recombinant vector was transformed into Escherichia coli TGl,and then rescued with the help of phage M13K07.Therefore a library of phage scFv antibody was constructed.After three rounds of enrichment screening and identification of Phage-ELISA,four strains of scFv antibodies to SIV were obtained from the library.This study provides a basis for the production of transgenic pigs against SIV.