IL22 | |||||||||||||||||||||||||||||||||||||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| |||||||||||||||||||||||||||||||||||||||||||||||||||
Identifiers | |||||||||||||||||||||||||||||||||||||||||||||||||||
Aliases | IL22 , IL-21, IL-22, IL-D110, IL-TIF, ILTIF, TIFIL-23, TIFa, zcyto18, interleukin 22 | ||||||||||||||||||||||||||||||||||||||||||||||||||
External IDs | OMIM: 605330 MGI: 2151139 HomoloGene: 9669 GeneCards: IL22 | ||||||||||||||||||||||||||||||||||||||||||||||||||
| |||||||||||||||||||||||||||||||||||||||||||||||||||
| |||||||||||||||||||||||||||||||||||||||||||||||||||
| |||||||||||||||||||||||||||||||||||||||||||||||||||
| |||||||||||||||||||||||||||||||||||||||||||||||||||
| |||||||||||||||||||||||||||||||||||||||||||||||||||
Wikidata | |||||||||||||||||||||||||||||||||||||||||||||||||||
|
Interleukin-22 (IL-22) is protein that in humans is encoded by the IL22 gene. [5] [6]
IL-22 is an α-helical cytokine. IL-22 binds to a heterodimeric cell surface receptor composed of IL-10R2 and IL-22R1 subunits. [7] IL-22R is expressed on tissue cells, and it is absent on immune cells. [8]
Crystallization is possible if the N-linked glycosylation sites are removed in mutants of IL-22 bound with high-affinity cell-surface receptor sIL-22R1. The crystallographic asymmetric unit contained two IL-22-sIL-22R1 complexes. [7]
IL-22 is produced by several populations of immune cells at a site of inflammation. Producers are αβ T-cell classes Th1, Th22 and Th17 along with γδ T cells, NKT, ILC3, neutrophils and macrophages. IL-22 takes effect on non-hematopoietic cells – mainly stromal and epithelial cells. Effects involve stimulation of cell survival, proliferation and synthesis of antimicrobials including S100, Reg3β, Reg3γ and defensins. IL-22 thus participates in both wound healing and in protection against microbes. [9] IL-22 dysregulation takes part in pathogenesis of several autoimmune diseases like systemic lupus erythematosus, rheumatoid arthritis and psoriasis. [10]
IL-22 biological activity is initiated by binding to a cell-surface complex composed of IL-22R1 and IL-10R2 receptor chains and further regulated by interactions with a soluble binding protein, IL-22BP, which shares sequence similarity with an extracellular region of IL-22R1 (sIL-22R1). IL-22 and IL-10 receptor chains play a role in cellular targeting and signal transduction to selectively initiate and regulate immune responses. [7] IL-22 can contribute to immune disease through the stimulation of inflammatory responses, S100s and defensins. IL-22 also promotes hepatocyte survival in the liver and epithelial cells in the lung and gut similar to IL-10. [11] In some contexts, the pro-inflammatory versus tissue-protective functions of IL-22 are regulated by the often co-expressed cytokine IL-17A [12]
Targets of this cytokine are mostly non-hematopoietic cells – epithelial and stromal cells of following tissues and organs: liver, lung, skin, thymus, pancreas, kidney, gastrointestinal tract, synovial tissues, heart, breast, eye and adipose tissue. [9]
IL-22 is a member of a group of cytokines called the IL-10 family or IL-10 superfamily (including IL-19, IL-20, IL-24, and IL-26), [13] a class of potent mediators of cellular inflammatory responses. It shares use of IL-10R2 in cell signaling with other members of this family, IL-10, IL-26, IL-28A/B and IL-29. [14]
IL-22, signals through the interferon receptor-related proteins CRF2-4 and IL-22R. [6] It forms cell surface complexes with IL-22R1 and IL-10R2 chains resulting in signal transduction through receptor, IL-10R2. The IL-22/IL-22R1/IL-10R2 complex activates intracellular kinases (JAK1, Tyk2, and MAP kinases) and transcription factors, especially STAT3. It can induce IL-20 and IL-24 signaling when IL-22R1 pairs with IL-20R2.
IL-22 production is induced mainly through IL-23 receptor signalling. IL-23 is produced by dendritic cells after recognition of ligands by specific Toll-like receptors especially in combination with Dectin-1 and or NOD2 signalling. IL-1β stimulates IL-22 production too. On the other hand IL-22 binding protein is a soluble inhibitor which blocks receptor binding site of IL-22. [9]
Interleukin-23 subunit alpha is a protein that in humans is encoded by the IL23A gene. The protein is also known as IL-23p19. It is one of the two subunits of the cytokine Interleukin-23.
Interleukin 30 (IL-30) forms one chain of the heterodimeric cytokine called interleukin 27 (IL-27), thus it is also called IL27-p28. IL-27 is composed of α chain p28 and β chain Epstain-Barr induce gene-3 (EBI3). The p28 subunit, or IL-30, has an important role as a part of IL-27, but it can be secreted as a separate monomer and has its own functions in the absence of EBI3. The discovery of IL-30 as individual cytokine is relatively new and thus its role in the modulation of the immune response is not fully understood.
Interleukin-26 (IL-26) is a protein that in humans is encoded by the IL26 gene.
Interleukin 24 (IL-24) is a protein in the interleukin family, a type of cytokine signaling molecule in the immune system. In humans, this protein is encoded by the IL24 gene.
Interleukin 17 family is a family of pro-inflammatory cystine knot cytokines. They are produced by a group of T helper cell known as T helper 17 cell in response to their stimulation with IL-23. Originally, Th17 was identified in 1993 by Rouvier et al. who isolated IL17A transcript from a rodent T-cell hybridoma. The protein encoded by IL17A is a founding member of IL-17 family. IL17A protein exhibits a high homology with a viral IL-17-like protein encoded in the genome of T-lymphotropic rhadinovirus Herpesvirus saimiri. In rodents, IL-17A is often referred to as CTLA8.
Interleukin 19 (IL-19) is an immunosuppressive protein that belongs to the IL-10 cytokine subfamily.
Interleukin-22 receptor subunit alpha-2 (IL-22RA2), also known as interleukin-22 binding protein (IL-22BP) is a naturally secreted monomeric protein acting as an interleukin-22 (IL-22) antagonist with inhibitory effects on IL-22 activity in vivo. IL-22BP is in humans encoded by the IL22RA2 gene located on chromosome 6, and in mice is encoded by the il22ra2 gene located on chromosome 10. IL-22BP belongs to the class II cytokine receptor family and it is a soluble receptor homolog of IL-22R.
T helper 17 cells (Th17) are a subset of pro-inflammatory T helper cells defined by their production of interleukin 17 (IL-17). They are related to T regulatory cells and the signals that cause Th17s to actually inhibit Treg differentiation. However, Th17s are developmentally distinct from Th1 and Th2 lineages. Th17 cells play an important role in maintaining mucosal barriers and contributing to pathogen clearance at mucosal surfaces; such protective and non-pathogenic Th17 cells have been termed as Treg17 cells.
Interleukin-36 gamma previously known as interleukin-1 family member 9 (IL1F9) is a protein that in humans is encoded by the IL36G gene.
Single Ig IL-1-related receptor (SIGIRR), also called Toll/Interleukin-1 receptor 8 (TIR8) or Interleukin-1 receptor 8 (IL-1R8), is transmembrane protein encoded by gene SIGIRR, which modulate inflammation, immune response, and tumorigenesis of colonic epithelial cells.
Interleukin 20 receptors (IL20R) belong to the IL-10 family. IL20R are involved in both pro-inflammatory and anti-inflammatory immune response. There are two types of IL20R: Type I and Type II.
Interleukin-28 receptor is a type II cytokine receptor found largely in epithelial cells. It binds type 3 interferons, interleukin-28 A, Interleukin-28B, interleukin 29 and interferon lambda 4. It consists of an α chain and shares a common β subunit with the interleukin-10 receptor. Binding to the interleukin-28 receptor, which is restricted to select cell types, is important for fighting infection. Binding of the type 3 interferons to the receptor results in activation of the JAK/STAT signaling pathway.
Interleukin-17A is a protein that in humans is encoded by the IL17A gene. In rodents, IL-17A used to be referred to as CTLA8, after the similarity with a viral gene.
Interleukin-17 receptor (IL-17R) is a cytokine receptor which belongs to new subfamily of receptors binding proinflammatory cytokine interleukin 17A, a member of IL-17 family ligands produced by T helper 17 cells (Th17). IL-17R family consists of 5 members: IL-17RA, IL-17RB, IL-17RC, IL-17RD and IL-17RE. Functional IL-17R is a transmembrane receptor complex usually consisting of one IL-17RA, which is a founding member of the family, and second other family subunit, thus forming heteromeric receptor binding different ligands. IL-17A, a founding member of IL-17 ligand family binds to heteromeric IL-17RA/RC receptor complex. IL-17RB binds preferentially IL-17B and IL-17E and heteromeric IL-17RA/RE complex binds IL-17C. However, there is still unknown ligand for IL-17RD. The first identified member IL-17RA is located on human chromosome 22, whereas other subunits IL-17RB to IL-17RD are encoded within human chromosome 3.
The IL-10 family is a family of interleukins.
Interleukin 23 (IL-23) is a heterodimeric cytokine composed of an IL-12B (IL-12p40) subunit and an IL-23A (IL-23p19) subunit. IL-23 is part of the IL-12 family of cytokines. The functional receptor for IL-23 consists of a heterodimer between IL-12Rβ1 and IL-23R.
Interleukin 22 receptor, alpha 1 is a protein that in humans is encoded by the IL22RA1 gene.
Type 3 innate lymphoid cells (ILC3) are immune cells from the lymphoid lineage that are part of the innate immune system. These cells participate in innate mechanisms on mucous membranes, contributing to tissue homeostasis, host-commensal mutualism and pathogen clearance. They are part of a heterogeneous group of innate lymphoid cells, which is traditionally divided into three subsets based on their expression of master transcription factors as well as secreted effector cytokines - ILC1, ILC2 and ILC3.
Interleukin 17F (IL-17F) is signaling protein that is in human is encoded by the IL17F gene and is considered a pro-inflammatory cytokine. This protein belongs to the interleukin 17 family and is mainly produced by the T helper 17 cells after their stimulation with interleukin 23. However, IL-17F can be also produced by a wide range of cell types, including innate immune cells and epithelial cells.
T helper cell 22, also known as the Th22 cell, are a type of immune cell. Th22 are a derivative of naïve CD4+ T cells induced by the ligand activation of the transcription factor aryl hydrocarbon receptor (AhR), which uses environmental, metabolic, microbial, and dietary cues to control complex transcriptional programmes. Th22 cell’s function is mediated by its ligand specific cytokine interleukin-22 (IL-22).