Cloning and expression of duck interleukin-2 gene and preparation of the monoclonal antibody against duck IL-2

The objective of this study is to prepare monoclonal antibody against duck IL-2.Duck IL-2gene was amplified by RT-PCR from spleen lymphocytes of Cherry Valley Ducks,and the expression plasmid pCold-DuIL2 was constructed.The recombinant protein was purified and used for immunization of BALB/c mice.The monoclonal antibody was identified by indirect ELISA and Western-bolt.The sub-types of mAbs were analyzed.Sequence analysis indicated that the encoding gene of duck IL-2(excluded the signal peptide sequence)was about 363bp in length and encode 120amino acids.SDS-PAGE analysis showed that the fusion protein was 65ku.All three clones of mAbs in ascitic fluids were shown to be with the titer of more than 5.12×105in ELISA assay,and the isotype of the three mAbs belonged to IgG2b.Western-blot analysis showed that the three mAbs could react with duck IL-2.In conclusion,the high titer monoclonal antibody was prepared successfully,which will benefit for developing methods for detecting the IL-2level in ducks.