Submitted to: Veterinary Immunology and Immunopathology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/5/2009
Publication Date: 12/1/2009
Citation: Yoo, J., Jang, S.I., Kim, S., Cho, J., Lee, H., Rhee, M.H., Lillehoj, H.S., Min, W. 2009. Molecular cloning and characterization of duck interleukin-17 . Veterinary Immunology and Immunopathology. 132:318-322. Interpretive Summary: Development of logical control strategy against many infectious diseases of poultry and other avian species critically depends on the availability of immunological knowledge and reagents that can be used in basic and applied research. In this paper, ARS scientists collaborated with scientists at the Gyeongsang National University in South Korea to clone and study biological function of important duck cytokine, IL-17 which is involved in the control of host innate immunity to many viral diseases such as avian influenza. In this report, scientists first identified duck IL-17 gene and studies its evolutionary closeness to chicken IL-17 gene. Using mouse monoclonal antibodies which detect specifically chicken IL-17, these scientists showed that many of these antibodies also recognize duck IL-17. These results showed the first immunological evidence that duck and chicken IL-17 evolved in parallel antigenically. Further studies in immunological function of these cytokines will provide enhanced insights on their role in mediating innate immunity in avian species.
Technical Abstract: Interleukin-17 (IL-17) belonging to the Th17 family is a proinflammatory cytokine produced by activated T cells. A 1034-bp cDNA encoding duck IL-17 (duIL-17) was cloned from ConA-activated splenic lymphocytes of ducks. The encoded protein, predicted to consisted of 169 amino acids, displayed a molecular weight of 18.8 kDa, a 29 residue NH2-terminal signal peptide, a single potential N-linked glycosylation site, and 6 cysteine residues conserved with mammalian IL-17s. Duck IL-17 shared 84% amino acid sequence identity to the previously described chicken IL-17 (chIL-17) and 36-47% to mammalian homologues and the open reading frame 13 of Herpesvirus saimiri (HVS 13). Genomic structure of duIL-17 was remarkably similar to those of chicken and mammalian conterparts. Transcript of duIL-17 could be strongly detected in ConA-activated splenic lymphocytes while a variety of normal tissues expressed at nondetectable levels by RT-PCR. Cross-reactivity of two mAbs against chIL-17 with duIL-17 was detected by indirect ELISA and Western blot analysis. These findings indicate that the structure of IL-17 is highly conserved among poultry, and two mAbs can be used for molecular and immunological studies of IL-17 in birds.