Figure 3

Effects of titania nanosurfaces on TLR expressions of macrophages Gene expression levels of toll-like receptor 2 (TLR2) and toll-like receptor 4 (TLR4), relative to glyceraldehyde 3-phosphate dehydrogenase (GAPDH), as analyzed by reverse transcription-polymerase chain reaction (RT-PCR), in J774A.1 cells cultured on a polystyrene culture plate for 3, 6, 12, and 24 h with or without M1-induction (A) or on polystyrene or smooth (SM), micro-roughened (MR), or nano-roughened (NR) 1 or NR2 surfaces with or without the M1-induction for days 1 and 3 (B). (C) Representative confocal laser microscopic images of F-actin (red), nuclear (blue), and TLR4 (green) staining, and the intensity of TLR4-labeled signals in the cells under different culture conditions. (D) Gene expression levels of TLR4 and TLR2, relative to GAPDH in the cells under serum-free conditions. White arrows indicate TLR4 fluorescence signals. Data represented as mean ± standard deviation (SD; N = 3 in A, B, and D) and box plots (N = 12–14 in C). Different letters indicate statistically significant differences (P < 0.05, Bonferroni multiple comparisons test in A and B, or Games–Howell test in C). UT, untreated cells; M1, M1-induced cells; M2, M2-induced cells; CTCF, Corrected total cell fluorescence. Note (C) the strong TLR4 signals in macrophages on the NR1 or NR2 titania surfaces (double arrows), in contrast with weaker signals on the other surfaces (arrows).