Fig. 1.

UHMWPE particle- and LPS-induced TNF-α secretion in THP-1 macrophages co-cultured with MG-63 osteoblasts. THP-1 macrophage-like cells co-cultured with MG-63 osteoblasts were stimulated with LPS or UHMWPE particles. The secretion of the pro-inflammatory cytokine TNF-α was quantified in cell culture supernatants. TNF-α secretion [pg/ml] by both co-cultures and controls as per 100.000 cells at 6 h of incubation is exemplarily shown. Absolute TNF-α cytokine levels secreted by activated co-cultures, THP-1 macrophages and MG-63 osteoblasts at 6 h of incubation is illustrated for stimulation with a high levels of LPS (100 ng/ml) and b UHMWPE particles (cell-to-particle ratio of 1:500). ***p < 0.001