title: Interleukin-26, a highly cationic T-cell cytokine targeting epithelial cells.
abstract: Interleukin-26 (IL-26) is a member of the IL-10 cytokine family due to sequence homology. IL-26 was discovered, since the gene is strongly overexpressed in T cells which are growth transformed by herpesvirus saimiri. The IL-26 gene maps to human chromosome 12q15 between the genes for two other T-cellular class-II cytokines, namely interferon-γ (lFN-γ) and lL-22. IL-26, IL-22, and IFN-γ are co expressed by activated T cells and, especially, by Th17 cells. IL-26 forms homodimers and adheres to glycosaminoglycans on cell surfaces, presumably due to its positive charge. IL-26 specifically targets the lL-26-specific heterodimeric receptor complex consisting of IL-20R1 and IL-10R2 which is typically expressed on epithelial cells such as colon carcinoma cells or keratinocytes. IL-26 stimulation induces STAT1 and STAT3 phosphorylation, CD54 surface expression, and cytokine secretion as shown for IL-8 and IL-10. IL-26 seems to act as a cell surface-associated and rather proinflammatory T-cell cytokine at the epithelial barrier, possibly linking T-cell response with epithelial functions.
authors.affiliation: Institute for Infection Medicine, Christian Albrecht University of Kiel and University Medical Center Schleswig-Holstein, Kiel, Germany.
authors.forename: Oliver
authors.initials: O
authors.lastname: Braum
authors.forename: Heide
authors.initials: H
authors.lastname: Pirzer
authors.forename: Helmut
authors.initials: H
authors.lastname: Fickenscher
mesh_terms: D000595:Amino Acid Sequence; D001327:Autoimmune Diseases / Q000209:etiology; D002472:Cell Transformation, Viral; D017124:Conserved Sequence; D004847:Epithelial Cells / Q000502:physiology*; D006801:Humans; D016753:Interleukin-10 / Q000502:physiology; D007378:Interleukins / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D018123:Receptors, Interleukin / Q000502:physiology; D011994:Recombinant Proteins; D015398:Signal Transduction / Q000502:physiology; D014158:Transcription, Genetic
chemical_list: C406767:IL26 protein, human; D007378:Interleukins; D012333:RNA, Messenger; D018123:Receptors, Interleukin; D011994:Recombinant Proteins; D016753:Interleukin-10; C422042:interleukin 20