The response of the human Jurkat T cell leukemia-derived cell line (Jurkat T cells) after 24 h of in vitro exposure to a titanium substrate (12 × 12 × 1 mm3) with a bilateral rough (Ra = 2.2-3.7 μm) titanium oxide coating (rTOC) applied using the micro-arc method in a 20% orthophosphoric acid solution was studied. A 1.5-fold down-regulation of hTERT mRNA expression and decreases in CD3, CD4, CD8, and CD95 presentation and IL-4 and TNFα secretion were observed. Jurkat T cell inactivation was not correlated with the generation of intracellular reactive oxygen species (ROS) and was not mediated by TiO2 nanoparticles with a diameter of 14 ± 8 nm at doses of 1 mg/L or 10 mg/L. The inhibitory effect of the rTOC (Ra = 2.2-3.7 μm) on the survival of Jurkat T cells (Spearman's coefficient rs = -0.95; n = 9; p < 0.0001) was demonstrated by an increase in the necrotic cell count among the cell population. In turn, an elevation of the Ra index of the rTOC was accompanied by a linear increase (r = 0.6; p < 0.000001, n = 60) in the magnitude of the negative electrostatic potential of the titanium oxide surface. Thus, the roughness of the rTOC induces an electrostatic potential and decreases the viability of the immortalized Jurkat T cells through mechanisms unrelated to ROS generation. This may be useful for replacement surgery applications of rough TiO2 implants in cancer patients.
Khlusov, I., Litvinova, L., Shupletsova, V., Khaziakhmatova, O., Melashchenko, E., Yurova, K., … Sharkeev, Y. (2018). Rough titanium oxide coating prepared by micro-arc oxidation causes down-regulation of hTERT expression, molecular presentation, and cytokine secretion in tumor Jurkat T cells. Materials, 11(3). https://doi.org/10.3390/ma11030360