Receptor for IL27. Requires IL6ST/GP130 to mediate signal transduction in response to IL27. This signaling system acts through STAT3 and STAT1. Acts as a receptor for the neuroprotective peptide humanin as part of a complex with IL6ST/GP130 and CNTFR (PubMed:19386761). Involved in the regulation of Th1-type immune responses. Also appears to be involved in innate defense mechanisms. Component of a receptor complex composed of IL6ST/GP130, IL27RA/WSX1 and CNTFR which interacts with the neuroprotective peptide humanin. Highly expressed in lymphoid tissues such as spleen, lymph nodes and peripheral blood leukocytes. Weakly expressed in other tissues examined including heart, brain, fetal and adult lung, liver, skeletal muscle, kidney, pancreas, prostate, testis, ovary, small intestine, kidney and colon. In the lymphoid system, higher level expression in CD4+ T-cell subsets than in CD8+ T-cell subsets. Also weaker expression in CD19+ B-cells and monocytes. The WSXWS motif appears to be necessary for proper protein folding and thereby efficient intracellular transport and cell-surface receptor binding. The box 1 motif is required for JAK interaction and/or activation. Belongs to the type I cytokine receptor family. Type 2 subfamily.