Intracellular Staining by Flow Cytometry
|Detection of IL‑19 in Human Peripheral Blood Monocytes by Flow Cytometry. Human peripheral blood monocytes cultured with LPS and monensin were stained with Mouse Anti-Human IL‑19 Fluorescein‑conjugated Monoclonal Antibody (Catalog # IC1035F) and Mouse Anti-Human CD163 PE‑conjugated Monoclonal Antibody (Catalog # FAB1607P). Quadrant markers were set based on control antibody staining (Catalog # IC0041F). View our protocol for Staining Intracellular Molecules.|
Human Interleukin 19 (IL-19) is a member of the IL-10 family of related cytokines. Its gene contains two alternate translation initiation sites, generating precursors of 215 amino acids (aa) and 177 aa, respectively. Both isoforms are processed to 17 kDa, 153 aa mature molecules. IL-19 contains seven helices and is secreted as a 35 kDa monomer. There are two potential N-linked glycosylation sites, and it is likely that the molecule is glycosylated. Mature human IL-19 shares 69% aa sequence identity with the mature mouse homologue. Although mouse IL-19 is active on human cells, human IL-19 is not active on mouse cells. IL-19 expression is limited to activated keratinocytes and monocytes. IL-19 binds a receptor complex consisting of the IL-20 receptor alpha (IL-20 R alpha, also known as IL-20 R1) and the IL-20 receptor beta (IL-20 R beta or IL-20 R2). This receptor complex is also shared by IL-20 and IL-24. Functionally, IL-19 induces IL-6 and TNF-alpha production by monocytes, and drives T-helper cell differentiation towards a Th2 response (1‑5).