Calcium Phosphate Coating Prepared by Microarc Oxidation Affects Expression, Molecular Presentation, and Cytokine Secretion in Tumor-Derived Jurkat T Cells.

Calcium phosphate (CaP) materials are among the best bone graft substitutes, but their use in the repair of damaged bone in tumor patients is still unclear. The human Jurkat T lymphoblast leukemia-derived cell line (Jurkat T cells) was exposed in vitro to a titanium (Ti) substrate (10 × 10 × 1 mm) with a bilateral rough (average roughness index () = 2-5 μm) CaP coating applied via the microarc oxidation (MAO) technique, and the morphofunctional response of the cells was studied. Scanning electron microscopy (SEM), X-ray diffraction (XRD), and energy dispersive X-ray spectroscope (EDX) analyses showed voltage-dependent (150-300 V) growth of structural ( index, mass, and thickness) and morphological surface and volume elements, a low Ca/P ratio (0.3-0.6), and the appearance of crystalline phases of CaHPO (monetite) and β-CaPO (calcium pyrophosphate). Cell and molecular reactions in 2-day and 14-day cultures differed strongly and correlated with the values. There was significant upregulation of expression (1.7-fold), IL-17 secretion, the presentation of the activation antigens CD25 (by 2.7%) and CD95 (by 5.15%) on CD4 cells, and 1.5-2-fold increased cell apoptosis and necrosis after two days of culture. Hyperactivation-dependent death of CD4 cells triggered by the surface roughness of the CaP coating was proposed. Conversely, a 3.2-fold downregulation in expression increased the percentages of CD4 cells and their CD95 subset (by 15.5% and 22.9%, respectively) and inhibited the secretion of 17 of 27 test cytokines/chemokines without a reduction in Jurkat T cell survival after 14 days of coculture. Thereafter, cell hypoergy and the selection of an independent viable CD4 subset of tumor cells were proposed. The possible role of negative zeta potentials and Ca as effectors of CaP roughness was discussed. The continuous (2-14 days) 1.5-6-fold reductions in the secretion of vascular endothelial growth factor (VEGF) by tumor cells correlated with the values of microarc CaP-coated Ti substrates seems to limit surgical stress-induced metastasis of lymphoid malignancies.