Development and characterization of mouse monoclonal antibodies specific for chicken interleukin 18

Four mouse monoclonal antibodies (mAbs) which are specific for chicken interleukin 18 (chIL18) were produced and characterized by enzyme-linked immunosorbent assay (ELISA), Western blotting, quantitative real-time PCR and neutralization assays. Using Western blot analysis, monoclonal antibodies specific for chIL18 identified a 23 kDa Pichia pastoris-expressed chIL18 and 66 kDa E. coli-derived MBP fusion protein of chIL18. Bioassays for chIL18 using primary chicken spleen cells showed dose-dependent IFN-γ mRNA expression and induction of IFN-γ from primary splenocytes, and triggered nitric oxide (NO) production in the HD11 macrophage cell line. These mAbs showed neutralizing chIL18 activity. Taken together, these mouse mAbs which detect chicken IL-18 will be significant new immune reagents and useful tools for basic and applied research in poultry.