Interferon-lambda receptor 1 (IFN-λR1)

Interferon-lambda receptor 1 (IFN-λR1 or IFNLR1) is a single-pass transmembrane receptor unique to type III interferons, forming a heterodimeric complex with IL-10R2 (interleukin-10 receptor beta) to mediate signaling of interferon-lambda cytokines (IFN-λ1/IL-29, IFN-λ2/IL-28A, IFN-λ3/IL-28B, and IFN-λ4)[3][2][1]. Structurally, IFN-λR1 consists of two extracellular fibronectin type III domains, a transmembrane region, and a cytoplasmic tail that associates with Janus kinase 1 (JAK1) to initiate downstream signaling through the JAK-STAT pathway[2][3]. Expression of IFN-λR1 is mainly restricted to epithelial cells and some immune cell subsets, conferring tissue selectivity for type III interferon action[1][3]. Signaling through this receptor complex induces antiviral, antiproliferative, and immunoregulatory gene expression, but with a more localized and sometimes less pro-inflammatory profile than type I interferon receptor signaling[3]. Therapeutically, IFN-λR1 is a target for pegylated interferon-lambda in clinical trials for viral infections such as hepatitis, and potentially for modulation of mucosal immunity in other infectious and inflammatory diseases[3].

Other names

IFNLR1IL-28 receptor alpha (IL-28RA)Interleukin-28 receptor alpha subunitInterleukin-28RACRF2-12

Activates interferon-stimulated gene expression via JAK-STAT signaling after binding by interferon-lambda ligands[3][1][2]. Modulates innate and adaptive immune responses, particularly at barrier surfaces. Induces antiviral state in cells with restricted tissue expression.