Fig. 2
TiO2 NPs induced expression of LFA-1, VLA-4 and αVβ3. U937 cells were exposed to TNFα (10 ng/mL) or to concentration of 0.001, 0.003, 0.01, 0.03, 0.3, 1, 3, 10, 30 and 100 μg/mL of TiO2 NPs of 50 nm during 18 h. a Histograms of the LFA-1 expression obtained by flow cytometry. The continuous line represents control unexposed cells and the dotted line corresponds to the different treatments. b Histograms of the VLA-4 expression obtained by flow cytometry. The continuous line represents control unexposed cells and the dotted line corresponds to the different treatments. c Histograms of the αVβ3 expression obtained by flow cytometry. The continuous line represents control unexposed cells and the dotted line corresponds to the different treatments. d-f Normalization of the results presented as as a percentage of expression (fluorescencence intensity with respect to control) as mean ± SD of three separate experiments. After 18 h of exposure to TiO2 NPs an expression of sLex and PSGL-1 was as strong as the induced by TNFα. *p < 0.05 vs negative control