A Reappraisal on the Potential Ability of Human Neutrophils to Express and Produce IL-17 Family Members In Vitro: Failure to Reproducibly Detect It

摘要: Neutrophils are known to perform a series of effector functions that crucial for the innate and adaptive responses, including synthesis secretion variety cytokines. In light controversial data in literature, main objective this study was more in-depth reevaluate capacity human neutrophils express produce cytokines IL-17 family vitro. By reverse transcription quantitative real-time PCR, protein measurement via commercial ELISA, immunohistochemistry (IHC) immunofluorescence (IF), flow cytometry, immunoblotting, chromatin immunoprecipitation (ChIP), ChIP-seq experiments, we found highly pure (>99.7%) populations do not express/produce IL-17A, IL-17F, IL-17AF, or IL-17B mRNA/protein upon incubation with agonists. Similar findings were observed by analyzing isolated from active psoriatic patients. contrast published studies, IL-17A IL-17F mRNA expression/production even when incubated extremely high concentrations IL-6 plus IL-23, regardless their combination inactivated hyphae conidia Aspergillus fumigatus. Consistently, no deposition histone marks (H3K27Ac) poised (H3K4me1) genomic regulatory elements detected at locus resting IL-23-stimulated neutrophils, indicating closed conformation. Concurrent experiments revealed some anti-IL-17A anti-IL-17B antibodies (Abs), although staining either spotted on cytospin slides present inflamed tissue samples IHC/IF, recognize intracellular having molecular weight corresponding IL-17B, respectively, immunoblotting whole neutrophil lysates. contrast, same Abs specifically other proteins suggesting ability positively stain preparations and, eventually, derives IL-17A- IL-17B-independent detections. sum, our confirm extend, also epigenetic level, previous inability purified mRNAs/proteins vitro, least under experimental conditions herein tested. Data provide number justifications explaining, part, why it is possible false detect IL-17A+-neutrophils.