Intracellular Staining by Flow Cytometry
|Detection of IL‑17C in PC‑3 Human Cell Line by Flow Cytometry. PC‑3 human prostate cancer cell line was stained with Mouse Anti-Human IL‑17C APC‑conjugated Monoclonal Antibody (Catalog # IC1234A, filled histogram) or isotype control antibody (Catalog # IC003A, open histogram). 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.|
The Interleukin-17 (IL-17) family proteins, comprising six members (IL-17/IL-17A through IL-17F), are secreted, structurally related proteins that share a conserved cysteine-knot fold near the C-terminus, but have considerable sequence divergence at the N-terminus (1, 2). With the exception of IL-17B, which exists as a non‑covalently linked dimer, all IL‑17 family members are disulfide-linked dimers (3). IL-17 family proteins are pro-inflammatory cytokines that induce local cytokine production and are involved in the regulation of immune functions (1, 2). Five receptors (IL-17 R, and IL-17RB through IL-17RE), which are likely activated by IL-17 family members, have been identified (1-4). Human IL-17C cDNA encodes a 197 amino acid (aa) residues protein with a putative 18 aa signal peptide (5). IL-17C shares from 15%‑30% aa sequence identity with other IL-17 family members. Human and mouse IL-17C also share 83% aa sequence identity. IL-17C has a very restricted expression pattern and was detected as a rare expressed sequence tag (EST) sequence in an adult prostate and fetal kidney libraries (2). As such, it is now known to be secreted by keratinocytes and colonic epithelium, and to act on epithelium via an IL-17RA:IL-17RE heterodimeric receptor. This is either an autocrine or paracrine activity (1,2,5). IL-17C has been shown to stimulate the release of proinflammatory cytokines and antimicrobial peptides such as S100A12, hBD, and CSF-3 (5, 6).