Abstract
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.
Highlights
A negative correlation was established between the TiO2 surface topography and the viable Jurkat T cell count after 24 h of culture, which was predominantly demonstrated by an increase in necrosis
A regression analysis showed a linear reduction in the proportion of viable T cells in the culture, whereas the roughness index, Ra, which is associated with the sample topography increased (Figure 4)
The data obtained in the present study suggest a certain toxic effect of the TiO2 coating that is mediated by inhibition of the genetic and secretory (IL-4) mechanisms supporting the proliferation of tumor Jurkat T cells
Summary
The highly proliferative Jurkat line of human leukemic T lymphoblast-like cells (Jurkat T cells) is widely used in toxicological research for the in vitro modeling of normal blood T lymphocyte reactions [1] and of the cells that are involved in acute T lymphoblastic leukemia and lymphoma [2].Because of largely similar immunophenotype and cytokine profile with human blood CD45CD3+primary cells, Jurkat T cells are actively used to study immune and cytotoxic reactions to anticancerMaterials 2018, 11, 360; doi:10.3390/ma11030360 www.mdpi.com/journal/materialsMaterials 2018, 11, 360 drugs [3] toxicants [4], and biomaterials [5], as well as ions [6] and titanium dioxide nanoparticles [7].The last two substrates are released during the biodegradation of endoprostheses and during triggered immunopathological reactions.Titanium is a modern biomaterial with bio-inert properties that is broadly used in various areas of biomedicine [8], primarily due to the ability of titanium dioxide to form surface metal-ceramic films [9].Recent publications provide evidence of the physicochemical properties of Ti surfaces transcending the bio-inert concept [10]. Materials 2018, 11, 360 drugs [3] toxicants [4], and biomaterials [5], as well as ions [6] and titanium dioxide nanoparticles [7]. Titanium is a modern biomaterial with bio-inert properties that is broadly used in various areas of biomedicine [8], primarily due to the ability of titanium dioxide to form surface metal-ceramic films [9]. Titanium dioxide is very insoluble, and biologically stable. It cannot pass undamaged skin, and even when inhaled or ingested, TiO2 is not thought to have serious effects on humans. There are reports indicating that TiO2 particles may be considered a biohazard [7]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
