Temporal associations between interleukin 22 and the extracellular domains of IL-22R and IL-10R2

• Published in: International immunopharmacology Vol. 4; no. 5; pp. 693 - 708
• Main Authors: Li, Jing, Tomkinson, Kathy N, Tan, Xiang-Yang, Wu, Paul, Yan, Grace, Spaulding, Vikki, Deng, Bijia, Annis-Freeman, Bethany, Heveron, Kathleen, Zollner, Richard, De Zutter, Gerard, Wright, Jill F, Crawford, Tara K, Liu, Wei, Jacobs, Kenneth A, Wolfman, Neil M, Ling, Vincent, Pittman, Debra D, Veldman, Geertruida M, Fouser, Lynette A
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01-05-2004
• Subjects: Animals; CHO Cells; Cricetinae; Dimerization; Enzyme-Linked Immunosorbent Assay - methods; Humans; IL-10R2; IL-22; IL-22 receptor complex; IL-22R; Interleukin-22; Interleukins - metabolism; Interleukins - pharmacology; Receptors, Interleukin - drug effects; Receptors, Interleukin - metabolism; Receptors, Interleukin-10; Time Factors; Bio-IL-22; IL-10R2; CRF2; βME; HRP; CHO; FLAG; NC 50; IL-22; IFN; IL-22BP; kD and kDa; BSA; P-STAT3; PBS; ECD; CM; IL-22R-Fc; IL-10R2-Fc; PBS-T; IL-22 receptor complex; SDS-PAGE; STAT; HIS; EC 50; IL-22BP-Fc; IL-22R; ELISA
• ISSN: 1567-5769; 1878-1705
• DOI: 10.1016/j.intimp.2004.01.010

Interleukin 22 (IL-22) is a cytokine induced during both innate and adaptive immune responses. It can effect an acute phase response, implicating a role for IL-22 in mechanisms of inflammation. IL-22 requires the presence of the IL-22 receptor (IL-22R) and IL-10 receptor 2 (IL-10R2) chains, two members of the class II cytokine receptor family (CRF2), to effect signal transduction within a cell. We studied the interaction between human IL-22 and the extracellular domains (ECD) of its receptor chains in an enzyme-linked immunoabsorbant assay (ELISA)-based format, using biotinylated IL-22 (bio-IL-22) and receptor-fusions containing the ECD of a receptor fused to the Fc of hIgG1 (IL-22R-Fc and IL-10R2-Fc). IL-22 has measurable affinity for IL-22R-Fc homodimer and undetectable affinity for IL-10R2. IL-22 has substantially greater affinity for IL-22R/IL-10R2-Fc heterodimers. Further analyses involving sequential additions of receptor homodimers and cytokine indicates that the IL-10R2
ECD binds to a surface created by the interaction between IL-22 and the IL-22R
ECD, and thereby further stabilizes the association of IL-22 within this cytokine–receptor-Fc complex. Both a neutralizing rat monoclonal antibody, specific for human IL-22, and human IL-22BP-Fc, an Fc-fusion of the secreted IL-22 binding-protein and proposed natural antagonist for IL-22, bind to similar cytokine epitopes that may overlap the binding site for IL-22R
ECD. Another rat monoclonal antibody, specific for IL-22, binds to an epitope that may overlap a separate binding site for IL-10R2
ECD. We propose, based on this data, a temporal model for the development of a functional IL-22 cytokine–receptor complex.