Fig. 4.

Effects of titanate nanomaterials on release of inflammatory cytokines by THP-1 cells. THP-1 cells were exposed to TF-1, TF-2, or TNP at a concentration of 25 µg/ml for 24 h. IL-8 (A, C) and TNF-α (B, D) were analyzed by ELISA. LPS (0.1 µg/ml) was used as a co-stimulant together with titanate nanomaterials (C, D). N.D. indicates that the cytokine concentration is below the detection limit and therefore could not be determined. The asterisk denotes statistical significance by a two-tailed Student's t-test relative to the control (p<0.05).