The Role of Dendritic Cells in Bone Loss and Repair

The cells of innate immunity, such as neutrophils, macrophages, and dendritic cells (DCs), stuck to the bone implant walls release reactive radicals, enzymes, and chemokines, which induced subsequent bone loss. DCs do not play a big role in bone homeostasis in steady-state conditions, but could act as osteoclasts precursors in inflammation foci of bone. The potent antigen-presenting cells responsible for activation of native T cells and modulation of T cell activity through RANK/RANKL pathway and other cytokines associated with osteoclastogenesis determine critically situated at the osteoimmune interface. The titanium (Ti) and magnesium (Mg), the metallic candidate in implant, including calcium-phosphate coating formation on them by method plasma electrolytic oxidation were used to evaluate the immune-modulatory effects of DCs. The calcium-phosphate coating on metals induced mature DC (mDC) phenotype, while Ti and Mg promoted a noninflammatory environment by supporting an immature DC (iDC) phenotype based on surface marker expression, cytokine production profiles, and cell morphology. These findings have numerous therapeutic implications in addition to DC’s important role in regulating innate and adaptive immunity. A direct contribution of these cells to inflammation-induced bone loss establishes DC as a promising therapeutic target, not only for controlling inflammation but also for modulating bone destruction

CORRECTIONAL EFFECT OF THE EXTERNAL ELECTROMAGNETIC FIELD ON BIOLOGICAL OBJECTS: EXPERIMENTAL STUDY

The action of a device for correcting a functional state consisting of two elements with active layers of ferromagnets, constructed on the chirality principle has been studied on living systems. It was found that, the electromagnetic field, generated by the device, did not have a cytotoxic effect on eukaryotic cells and increased the killer potential of innate immunity cells against Candida albicans. Morphological analysis of tissue structure of animals target organs infected with C. albicans showed, that when receiving water charged with the device under test, less pronounced signs of toxic inflammation are observed, than in animals that did not take this water

INFLUENCE OF BIOCOMPATIBLE COATINGS ON MAGNESIUM ON THE FUNCTIONAL STATE OF MESENCHYMAL STEM CELLS

This article reports the bioactive resorptive coatings, formed on magnesium alloy substrates, using the method of plasma electrolytic oxidation (PEO), and their cytocompatibility with bone marrow derived mesenchymal stem cells (MSC). Were obtained the protective coatings containing hydroxyapatite with a ratio Ca/P = 1.6 close to the bone tissue index (1.67) on the magnesium alloy MA8 in the electrolyte solution containing calcium glycerophosphate and sodium fluoride in the bipolar regime of PEO. These coatings have a developed porous surface and significantly reduce the rate of corrosion of the magnesium alloy, which makes it possible to consider them as perspective for bioresorbable medical implants. Such bioactive coatings that modify the surface of magnesium provide a porous surface that promotes the strong attachment of MSCs