IL-10R2

Interleukin-10 receptor beta (IL-10Rβ, gene IL10RB, also called IL-10R2 or CD210B) is the shared signal-transducing accessory chain of four class II cytokine receptor complexes: the IL-10 receptor (with IL-10Rα), the IL-22 receptor (with IL-22RA1), and the type III interferon receptor (with IFNLR1), as well as the IL-28/IFN-λ receptor system. Unlike the private alpha chains that dictate ligand specificity, IL-10Rβ is expressed relatively broadly on hematopoietic and non-hematopoietic cells, including T cells, monocytes, B cells, hepatocytes and intestinal epithelium, expanding the tissues able to respond to these cytokines. Its cytoplasmic domain constitutively associates with TYK2, and ligand-induced receptor reorganization juxtaposes TYK2 with JAK1 on the partner chain, culminating in STAT1/STAT2/STAT3 activation depending on the complex. Human IL10RB deficiency presents as severe combined immunodeficiency with infantile-onset inflammatory bowel disease, owing to combined failure of IL-10 and IL-22 mucosal defense, underscoring the indispensable multitasking nature of this receptor subunit.