Intracellular Staining by Flow Cytometry
|Detection of IL‑26/AK155 in Human PBMCs by Flow Cytometry. Human peripheral blood mononuclear cells (PBMCs) either (A) untreated or (B) treated with PMA and Calcium Ionomycin were stained with Mouse Anti-Human IL‑26/AK155 PE‑conjugated Monoclonal Antibody (Catalog # IC13751P) and Mouse Anti-Human CD3 epsilon APC‑conjugated Monoclonal Antibody (Catalog # FAB100A). Quadrant markers were set based on control antibody staining (Catalog # IC002P). To facilitate intracellular staining, cells were fixed with Flow Cytometry Fixation Buffer (Catalog # FC004) and permeabilized with Flow Cytometry Permeabilization/Wash Buffer I (Catalog # FC005). View our protocol for Staining Intracellular Molecules.|
IL-26 was originally cloned from herpesvirus saimiri (HVS)-transformed T cells and named AK155. It is a member of the IL-10 family of class II cytokines that signal via heterodimeric receptor complexes composed of two type I transmembrane receptor subunits. The human IL-26 gene has been mapped to chromosome 12q15. It encodes a 171 amino acid polypeptide with a 21 amino acid signal peptide. In addition to HVS-transformed T cells, IL-26 is also expressed in other virus transformed T cell lines, fresh peripheral mononuclear cells, activated NK cells and T cells. A mouse homologue of human IL-26 has not been identified. IL-26 binds with high-affinity to the heterodimeric complex consisting of the ligand-binding IL-20 R alpha and non ligand-binding IL-10 R beta. Activation of the receptor complex results in rapid phosphorylation of STAT1 and STAT3. Although the IL-26 receptor complex is highly specific for IL-26 and is not activated by other class II cytokines, the individual subunits of the IL-26 receptor complex are components in receptor complexes for other class II cytokines. IL-20 R alpha can form dimers with IL-20 R beta to function as signaling receptors for IL-19, IL-20, and IL-24. IL-10 R beta can complex with IL-10 R alpha, IL-22 R, and IL-28 R alpha to transduce signals for IL-10, IL-22, and the three novel IFNs (IL-28A, IL-28B and IL-29), respectively. The physiological functions of IL-26 remain to be determined. IL-26 was reported to be a homodimer in solution.