Hydroxychloroquine inhibits IL-1\u03b2 production from amyloid-stimulated human neutrophils

Yuya Fujita,Shuzo Sato,Hideko Kozuru,Hiroshi Watanabe,Jumpei Temmoku,Kiyoshi Migita,Tomoyuki Asano,Hiroshi Yatsuhashi,Naoki Matsuoka,Hiroko Kobayashi,Atsushi Kawakami,Takeshi Urano,Makiko Yashiro Furuya,Tomohiro Koga,Eiji Suzuki

doi:10.1186/s13075-019-2040-6

Abstract

BackgroundHydroxychloroquine (HCQ) is used for the treatment of patients with rheumatic diseases. We tested the hypothesis that HCQ affects the NLRP3 inflammasome, which is involved in autoinflammation.MethodsHuman neutrophils were stimulated with serum amyloid A (SAA) in vitro and measured for IL-1β and caspase-1 (p20) secretion by ELISA. Pro-IL-1β mRNA expression in human neutrophils was quantified by real-time RT-PCR.ResultsSAA stimulation induced significant production of IL-1β in human neutrophils. SAA stimulation also induced NF-κB activation, pro-IL-1β mRNA expression, and NLRP3 protein expression in human neutrophils. HCQ pretreatment significantly inhibited the SAA-induced IL-1β production in human neutrophils, but did not affect the SAA-induced NF-κB activation, pro-IL-1β mRNA expression, and NLRP3 protein expression. Furthermore, SAA stimulation induced cleaved caspase-1 (p20) secretion from human neutrophils, and this release was suppressed by HCQ pretreatment.ConclusionsTreatment with HCQ was associated with impaired production of IL-1β in SAA-stimulated human neutrophils without affecting the priming process of the NLRP3 inflammasome such as pro-IL-1β or NLRP3 induction. These findings suggest that HCQ affects the NLRP3 activation process, resulting in the impaired IL-1β production in human neutrophils, as representative innate immune cells.

Highlights

Hydroxychloroquine (HCQ) is used for the treatment of patients with rheumatic diseases
We previously showed that serum amyloid A (SSA) is capable of inducing IL-1β secretion from human neutrophils without a priming signal [12]
We investigated the effect of HCQ on serum amyloid A (SAA)-induced NLR family pyrin domain containing 3 (NLRP3) inflammasome activation and subsequent IL-1β secretion in human neutrophils

Summary

Introduction

Hydroxychloroquine (HCQ) is used for the treatment of patients with rheumatic diseases. Hydroxychloroquine (HCQ) exerts various antiinflammatory and immunomodulatory effects and is widely used for the treatment of rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE) [1]. SAA has been identified as an endogenous activator of the NLRP3 inflammasome, which is critical for pro-IL-1β processing and activation [8]. Inflammasome-targeted therapies appear to be a new approach for lupus treatment. Because of the diverse effects of HCQ on patternrecognition receptors [11], it is tempting to speculate that the inflammasome could be a target for HCQ during innate immune cell activation. We directly addressed the above hypothesis by determining the effects of HCQ on the NLRP3 inflammasome activation process using human neutrophils as representative innate immune cells. The present findings provide novel insights toward understanding the anti-inflammatory effects of HCQ on the innate immune system

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Results

Discussion

Conclusion