OBJECTIVE: To determine whether monosodium urate (MSU) crystal-induced superoxide production is greater for neutrophils from patients with gout compared to asymptomatic hyperuricemic and healthy controls, and whether neutrophil functions are altered by an MSU crystal-induced inflammatory environment. METHODS: Neutrophils were purified from the whole blood of study participants, restimulated with 500 mg MSU crystals ex vivo, and superoxide production measured using the colorimetric dye WST-1. Purified neutrophils were exposed to conditioned media from MSU crystal-activated blood monocyte cultures with and without neutralizing antibodies for interleukin 1ss (IL-1ss), IL-8 (CXCL8), IL-6, and tumor necrosis factor-alpha (TNF-alpha). Neutrophil superoxide production was measured and neutrophil apoptosis and IL-8 production were determined by flow cytometry. Serum samples were collected from participants and analyzed by Lincoplex bead array for IL-1ss, IL-8, IL-6, and TNF-alpha. RESULTS: Neutrophils from gout and asymptomatic hyperuricemic subjects produced higher levels of MSU crystal-induced superoxide, and a weak trend toward elevated serum cytokines was observed compared to healthy controls. A correlation between serum uric acid and elevated neutrophil superoxide production was also observed. Neutrophils exposed to media from MSU crystal-activated monocytes exhibited enhanced superoxide production to MSU-crystal stimulation, increased IL-8 production, and extended cell survival that was predominantly dependent on IL-8, TNF-alpha and IL-6, respectively. CONCLUSION: Neutrophils from gout and asymptomatic hyperuricemic individuals are primed for enhanced MSU crystal-induced superoxide production that may be driven by a subclinical inflammatory cytokine environment combined with hyperuricemia. This inflammatory environment likely contributes to elevated neutrophil IL-8 production and survival in the absence of direct crystal stimulation. Asymptomatic hyperuricemia is not associated with suppressed neutrophil function.
OBJECTIVE: To determine whether monosodium urate (MSU) crystal-induced superoxide production is greater for neutrophils from patients with gout compared to asymptomatic hyperuricemic and healthy controls, and whether neutrophil functions are altered by an MSU crystal-induced inflammatory environment. METHODS: Neutrophils were purified from the whole blood of study participants, restimulated with 500 mg MSU crystals ex vivo, and superoxide production measured using the colorimetric dye WST-1. Purified neutrophils were exposed to conditioned media from MSU crystal-activated blood monocyte cultures with and without neutralizing antibodies for interleukin 1ss (IL-1ss), IL-8 (CXCL8), IL-6, and tumor necrosis factor-alpha (TNF-alpha). Neutrophil superoxide production was measured and neutrophil apoptosis and IL-8 production were determined by flow cytometry. Serum samples were collected from participants and analyzed by Lincoplex bead array for IL-1ss, IL-8, IL-6, and TNF-alpha. RESULTS: Neutrophils from gout and asymptomatic hyperuricemic subjects produced higher levels of MSU crystal-induced superoxide, and a weak trend toward elevated serum cytokines was observed compared to healthy controls. A correlation between serum uric acid and elevated neutrophil superoxide production was also observed. Neutrophils exposed to media from MSU crystal-activated monocytes exhibited enhanced superoxide production to MSU-crystal stimulation, increased IL-8 production, and extended cell survival that was predominantly dependent on IL-8, TNF-alpha and IL-6, respectively. CONCLUSION: Neutrophils from gout and asymptomatic hyperuricemic individuals are primed for enhanced MSU crystal-induced superoxide production that may be driven by a subclinical inflammatory cytokine environment combined with hyperuricemia. This inflammatory environment likely contributes to elevated neutrophil IL-8 production and survival in the absence of direct crystal stimulation. Asymptomatic hyperuricemia is not associated with suppressed neutrophil function.
Authors: Rebecca Grainger; Nicola Dalbeth; Helen Keen; Laura Durcan; N Lawrence Edwards; Fernando Perez-Ruiz; Cesar Diaz-Torne; Jasvinder A Singh; Dinesh Khanna; Lee S Simon; William J Taylor Journal: J Rheumatol Date: 2015-02-01 Impact factor: 4.666
Authors: Kyle Caution; Nicholas Young; Frank Robledo-Avila; Kathrin Krause; Arwa Abu Khweek; Kaitlin Hamilton; Asmaa Badr; Anup Vaidya; Kylene Daily; Hawin Gosu; Midhun N K Anne; Mostafa Eltobgy; Duaa Dakhlallah; Sudha Argwal; Shady Estfanous; Xiaoli Zhang; Santiago Partida-Sanchez; Mikhail A Gavrilin; Wael N Jarjour; Amal O Amer Journal: Front Immunol Date: 2019-11-15 Impact factor: 7.561
Authors: Kyle Jablonski; Nicholas A Young; Caitlin Henry; Kyle Caution; Anuradha Kalyanasundaram; Ifeoma Okafor; Peter Harb; Emmy Schwarz; Paul Consiglio; Chris M Cirimotich; Anna Bratasz; Anasuya Sarkar; Amal O Amer; Wael N Jarjour; Naomi Schlesinger Journal: PLoS One Date: 2020-10-01 Impact factor: 3.240