Fig. 2

Impact of recombinant human proteoglycan-4 (rhPRG4) treatment on monosodium urate monohydrate (MSU) crystal-induced expression and production of proinflammatory cytokines and chemokines and nuclear factor kappa b (NFκB) p65 subunit nuclear translocation in THP-1 macrophages. Cytokines included interleukin-1 beta (IL-1β) and tumor necrosis factor alpha (TNF-α). Chemokines included interleukin-8 (IL-8) and monocyte chemoattractant protein-1 (MCP-1). Gene expression data are presented as fold induction of proinflammatory cytokines and chemokines gene expression compared to control untreated THP-1 macrophages. THP-1 macrophages were treated with MSU crystals (100μg/ml) ± rhPRG4 (100μg/ml) or bovine submaxillary mucin (BSM; 25μg/ml) for 6 h (a through d). NFκB p65 subunit nuclear translocation in THP-1 macrophages was performed at 1 h following MSU challenge (100μg/ml). Gene expression studies were performed at 6 h (f through i) and cytokine and chemokine media concentrations were determined at 24 h (j through m). Data represent the mean ± S.D. of three to four independent experiments with duplicate wells per group. *p < 0.001; **p < 0.01; ***p < 0.05. a rhPRG4 treatment reduced MSU-stimulated production of IL-1β by THP-1 macrophages. b rhPRG4 treatment reduced MSU-stimulated production of TNF-α by THP-1 macrophages. c rhPRG4 treatment reduced MSU-stimulated production of IL-8 by THP-1 macrophages. d rhPRG4 treatment reduced MSU-stimulated production of MCP-1 by THP-1 macrophages. e rhPRG4 treatment reduced MSU-stimulated NFκB p65 subunit nuclear translocation in THP-1 macrophages. f rhPRG4 (100 and 200μg/ml) treatment reduced IL-1β gene expression in MSU-stimulated THP-1 macrophages. g rhPRG4 (25, 50, 100 and 200μg/ml) treatment reduced TNF-α gene expression in MSU-stimulated THP-1 macrophages. h rhPRG4 (50, 100 and 200μg/ml) treatment reduced IL-8 gene expression in MSU-stimulated THP-1 macrophages. i rhPRG4 (50, 100 and 200μg/ml) treatment reduced MCP-1 gene expression in MSU-stimulated THP-1 macrophages. j rhPRG4 (100 and 200μg/ml) treatment reduced IL-1β production by MSU-stimulated THP-1 macrophages. k rhPRG4 (100 and 200μg/ml) treatment reduced TNF-α production by MSU-stimulated THP-1 macrophages. l rhPRG4 (200μg/ml) treatment reduced IL-8 production by MSU-stimulated THP-1 macrophages. m rhPRG4 (200μg/ml) treatment reduced MCP-1 production by MSU-stimulated THP-1 macrophages