Production and characterization of monoclonal antibodies detecting chickeninterleukin-2 and the development of an antigen capture enzyme-linked immunosorbent assay

Eleven monoclonal antibodies (mAbs) which are specific for chicken interleu kin-2 (chIL-2) were produced and characterized by enzyme-linked immunosorbe nt assay (ELISA), Western blotting and neutralizing assays. These mAbs were used to develop a mAb-based antigen capture ELISA specific for chicken IL- 2 detection. Anti-IL-2 mAbs bound specifically to E. coli-derived rchIL-2 i n ELISA and identified a 16 kDa IL-2 polypeptide band in Western blot. Seve ral mAbs were shown to neutralize the biological activities of both rchIL-2 and native chicken IL-2 as measured by concanavalin A (ConA)-induced lymph ocyte proliferation assay, IL-2 bioassay, and natural killer cell assay. Am ong the neutralizing mAbs, the mAb chIL-2/11 was most potent in neutralizin g IL-2 activity. To develop a sensitive ELISA for the detection of chicken IL-2, an antigen capture ELISA was developed using the mAb chIL-2/16 as the antigen capture antibody and rabbit anti-IL-2 peptide antibody as the dete ction antibody. Using the mAb-based antigen capture ELISA, significant corr elation between the level of IL-2 detected in bioassays and in ELISA was ob served. These results showed that the ni-Ab-based antigen capture ELISA is less time-consuming and more reliable compared to a conventional IL-2 bioas say for chicken IL-2. These neutralizing mAbs will facilitate basic immunob iological studies of the role of IL-2 in normal and disease states in chick ens. Published by Elsevier Science B.V.