The IFN-lambda 4 Conundrum: When a Good Interferon Goes Bad
JOURNAL OF INTERFERON AND CYTOKINE RESEARCH
Authors: Onabajo, Olusegun O.; Muchmore, Brian; Prokunina-Olsson, Ludmila
Abstract
Since its discovery in 2013, interferon lambda 4 (IFN-lambda 4) has received a reputation as a paradoxical type III IFN. Difficulties in detecting IFN-lambda 4, especially in secreted form even led to questions about its existence. However, the genetic ability to generate IFN-lambda 4, determined by the presence of the rs368234815-Delta G allele, is the strongest predictor of impaired clearance of hepatitis C virus (HCV) infection in humans. Significant modulation of IFN-lambda 4 activity by a genetic variant (P70S) supports IFN-lambda 4, and not other type III IFNs encoded in the same genomic locus, as the primary functional cause of the association with HCV clearance. Although the ability to produce IFN-lambda 4 is associated with decreased HCV clearance, the recombinant IFN-lambda 4 is active against HCV and other viruses. These observations present an apparent conundrum-when and how does a presumably good IFN, with anti-HCV activity, interfere with the ability to clear HCV? In this review, we discuss findings that suggest potential mechanisms for explaining this conundrum.
Inhibition of microRNA-132 attenuates inflammatory response and detrusor fibrosis in rats with interstitial cystitis via the JAK-STAT signaling pathway
JOURNAL OF CELLULAR BIOCHEMISTRY
Authors: Song, Ya-Jun; Cao, Jun-Ying; Jin, Zhuang; Hu, Wen-Gang; Wu, Rong-Hua; Tian, Lu-Hai; Yang, Bo; Wang, Jin; Xiao, Ya; Huang, Chi-Bing
Abstract
Interstitial cystitis (IC) is a heterogeneous syndrome with unknown etiology, and microRNAs (miRs) were found to be involved in IC. In our study, we aim to explore the role of miR-132 in the inflammatory response and detrusor fibrosis in IC through the Janus kinase-signal transducer and activator of transcription (JAK-STAT) signaling pathway in rat models. A rat model of IC was established and treated with the miR-132 mimic, miR-132 inhibitor, and/or JAK-STAT signaling pathway inhibitor AG490. Enzyme-linked immunosorbent assay was applied to measure the expression of interleukin (IL)-6, IL-10, interferon- (IFN-), and tumor necrosis factor- (TNF-), and intercellular adhesion molecule-1 (ICAM-1). The urodynamic test was performed to assess urodynamic parameters, and reverse transcription quantitative polymerase chain reaction and Western blot analysis for the expression of miR-132, STAT4, suppressors of cytokine signaling 3 (SOCS3), JAK2, vascular endothelial growth factor (VEGF), IFN-, and TNF-. IC rats treated with miR-132 inhibitor and AG490 had decreased collagen fiber, inflammatory cell infiltration, and mast cells, lower expression of IL-6, IL-10, IFN-, TNF-, ICAM-1, collagens I and III, and alleviated urodynamic parameters and decreased expression of STAT4, VEGF, JAK2, IFN-, TNF-, and increased expression of SOCS3. Taken together, our data indicate that downregulation of miR-132 alleviates inflammatory response and detrusor fibrosis in IC via the inhibition of the JAK-STAT signaling pathway.