MD-2 Determinants of Nickel and Cobalt-Mediated Activation of Human TLR4
Fig 2
Nickel and cobalt trigger cytokine production and phosphorylation of intracellular signaling proteins.
(A) Nickel and cobalt stimulation elicits hIL-8 production. HUVEC cells were stimulated with LPS, nickel or cobalt for either 6 or 16 hours. hIL-8 concentration was measured in cell culture supernatants by ELISA. (B) THP-1 cells were stimulated with LPS or metal ions for 16 hours. Cytokine concentration was measured in cell culture supernatants by ELISA. (C) THP-1 cells were stimulated and the phosphorylation of the inhibitor of kappaB-alpha was detected with western blot. #p≥0,01 (not significant); *p<0,01; **p<0,001; ***p<0,0001 (t-test, compared to the unstimulated control). (D) THP-1 cells were stimulated with LPS alone or simultaneously with nickel for 6h. hTNF-α concentration was measured in cell culture supernatants by ELISA. #p≥0,01 (not significant); *p<0,01; **p<0,001; ***p<0,0001 (t-test, compared to the unstimulated control (as indicated by brackets) or compared to the cells not treated with nickel).