Interleukin-20 receptor subunit alpha and Interleukin-20 receptor subunit beta heterodimer (IL-20Rα/IL-20Rβ)

The Interleukin-20 receptor subunit alpha/beta heterodimer, also known as the Type I IL-20 receptor complex, is a transmembrane receptor belonging to the Type II cytokine receptor family [1, 2]. It is composed of two subunits: the Interleukin-20 receptor subunit alpha (IL-20RA) and the Interleukin-20 receptor subunit beta (IL-20RB) [1, 9]. This receptor complex is primarily expressed on epithelial cells, such as keratinocytes, and serves as the functional receptor for IL-19, IL-20, and IL-24 [1, 6]. Upon ligand binding, the receptor activates the Janus kinase (JAK) and Signal Transducer and Activator of Transcription (STAT) pathway, particularly STAT3, which regulates genes involved in cell proliferation, differentiation, and inflammatory responses [1, 12]. Dysregulation of this signaling pathway is strongly implicated in the pathogenesis of chronic inflammatory and autoimmune diseases, most notably psoriasis and rheumatoid arthritis [11, 13]. In psoriasis, the receptor is significantly upregulated in skin lesions, where it promotes keratinocyte hyperproliferation and prevents terminal differentiation [13, 16]. It also plays roles in atherosclerosis, osteoporosis, and certain cancers by modulating tissue repair and inflammatory environments [3, 34]. Therapeutic strategies targeting this receptor or its ligands, such as the monoclonal antibody fletikumab, have been explored in clinical trials to mitigate excessive inflammation [18, 22]. However, some clinical trials have faced challenges regarding efficacy, leading to the termination of certain development programs [26]. Ongoing research continues to investigate the receptor's potential as a target in oncology and other inflammatory conditions [34, 35].

Other names

IL-20R1/IL-20R2Type I IL-20 receptor complexIL-20RA/IL-20RBInterleukin-20 receptor subunit alpha/beta heterodimer

Antagonism of ligand binding and inhibition of downstream JAK/STAT signaling pathways.