Location: Animal Parasitic Diseases
Title: Molecular characterization and immunological roles of avian IL-22 and its soluble receptor IL-22 binding protein Authors
Submitted to: Cytokine
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: August 6, 2012
Publication Date: September 11, 2012
Citation: Kim, S., Faris, L., Cox, C., Summers, L., Jenkins, M.C., Fetterer, R.H., Miska, K.B., Dalloul, R. 2012. Molecular characterization and immunological roles of avian IL-22 and its soluble receptor IL-22 binding protein. Cytokine. 60:815. Interpretive Summary: More than 8 billion broiler chickens are produced annually in the US. Control of infectious diseases is essential to sustain this productivity and to maintain the health of broiler flocks. Current methods to control infections rely heavily on antibiotics and anti-parasitic drugs. Because of development of drug resistant pathogens and the desire to reduce the use of antibiotics and other drugs in food animals, new controls for infectious diseases of poultry are needed. Understanding the bird’s natural responses to infection can be a way to develop new methods of control. IL-22 is a protein that that belongs to a group of molecules called cytokines that are potent mediators of tissue inflammation caused by infection with bacteria, parasites and other pathogens and are important in the chicken’s innate response to infection. Understanding of the function of IL-22 and related molecules in chickens is important to understanding the bird’s response to infections by pathogens. The current research characterizes the molecular properties of chicken Il-22 and for the first time indentifies the active site (receptor) on the surface of intestinal and liver cells. The results of this research will provide new tools that can be useful in understanding and enhancing the chicken’s immune response to infection.
Technical Abstract: As a member of the interleukin (IL)-10 family, IL-22 is an important mediator in modulating tissue responses during inflammation. Through activation of STAT3-signaling cascades, IL-22 induces proliferative and anti-apoptotic pathways, as well as antimicrobial peptides (AMPs), that help prevent tissue damage and aid in its repair. This study reports the cloning and expression of recombinant chicken IL-22(rChIL-22) and its soluble receptor, rChIL22BP, and characterization of biological effects of rChIL-22 during inflammatory responses. Similar to observations with mammalian IL-22, purified rChIL-22 had no effect on either peripheral blood mononuclear cells (PBMCs) or lymphocytes. This was due to the low expression of the receptor ChIL22RA1 chain compared to ChIL10RB chain. rChIL-22 alone did not affect chicken embryo kidney cells (CEKCs); however, co-stimulation of CEKCs with LPS and rChIL-22 enhanced the production of pro-inflammatory cytokines, chemokines and AMPs. Furthermore, rChIL-22 alone stimulated and induced acute phase reactants in chicken embryo liver cells (CELCs). These effects of rChIL-22 were abolished by pre-incubation of rChIL-22 with rChIL22BP. Together, this study indicates an important role of ChIL-22 on epithelial cells and hepatocytes during inflammation.