S. aureus and E. coli change the force and work of adhesion between P- and E-selectins of endothelial cells and ligands of neutrophil granulocytes.

Thanks to the modification of the force spectroscopy method, when a neutrophil is fixed on the tip, and an endotheliocyte culture is grown on the substrate, the exact indicators of the adhesion force and adhesion work between cells have been investigated. The high variability of adhesion contacts in different donors associated with different expression profiles of neutrophils. It was found by flow cytometry that the EA.hy926 cell line actively expresses VCAM-1, as well as P- and E-selectin under the Staphylococcus aureus influence after 60 min of co-incubation. At the same time, the integral indicators of the adhesion force and adhesion work in the "neutrophil - endothelial cell" interaction were significantly inhibited by S. aureus in all studied donors. Since the VCAM-1 receptor is not involved in the adhesion bonds between neutrophils and endothelial cells, the suppression of the interaction is associated with the inhibition of P- and E-selectins, but direct receptors removal from the endothelial cells surface of the EA.hy926 cell line does not occur. Escherichia coli causes multidirectional effects in the system of interaction "neutrophil - endothelial cell", depending on the expression profile of the donor's neutrophils. However, the cumulative effect of interaction from all donors shows that in general, under the influence of E. coli, there is an increase in adhesion force and a suppression of adhesion work.

Influence of Quantum Dots Protein Crown on the Morphology and Morphometric Characteristics of Lymphocytes.

The incubation of quantum dots with lymphocytes induced significant changes in all morphometric characteristics of these cells. Protein crown formed on the surface of quantum dots after incubation with the serum consists mainly of transport proteins, immunoglobulins, blood coagulation proteins, and kininogens. Protein crown changes the morphometric characteristics of cells: in the case of incubation with quantum dots that have low-molecular-weight coating, a shift towards control parameters (cells without exposure) was observed; on the contrary, after incubation with quantum dots that have a high-molecular-weight coating, the differences from the control became more pronounced. It can be hypothesized that protein crown provokes autoagression of lymphocytes against each other and against platelets.

Serum Protein Corona Abolishes Changes in the Expression of Proinflammatory Genes Induced by Quantum Dots in Human Blood Mononuclear Cell.

We studied changes in the transcription of genes encoding cytokines (TNF, IL-6, IL-10, and IL-32), cell activation markers (ICAM1, CD38, Fas, and FCGRIII), ROS production catalyst (NOX2), autophagy (Beclin 1, LC3B, and p62) and apoptosis (BAX, BCL2) regulators in peripheral blood mononuclear cells upon contact with quantum dots CdSe/ZnS-MPA and CdSe/CdSeZnS/ZnS-PTVP. Up-regulation of TNF, ICAM1, Fas, p62 mRNA and down-regulation of the FCGRIII and NOX2 mRNA in response to the presence of quantum dots were revealed. The formation of serum protein corona on the surface of quantum dots abolished this effect.

Differences between Neutrophilic Granulocytes and Lymphocytes in Fixation of Quantum Dots of Different Composition.

Studies by flow cytometry, scanning electron microscopy, and X-ray microanalysis have shown that fixation/internalization of quantum dots differ in lymphocytes and neutrophilic granulocytes. Punctate fixation of quantum dots to cell surface is characteristic of lymphocytes, while phagocytosis with perinuclear location of quantum dot aggregations is characteristic of neutrophils. The presence of complex functional groups on the surface of quantum dots can inhibit significantly the fixation/internalization of quantum dots by blood cells.

Characteristics of quantum dots phagocytosis by neutrophil granulocytes.

This article describes the main morphological and biochemical features of neutrophil granulocytes in the process of phagocytosis of two types of quantum dots (CdSe/ZnS-MPA and CdSe/CdSeZnS/ZnS-PTVP). This study is the first to observe the transfer of large aggregates of quantum dots through neutrophils. During this process the cells demonstrate high chemotactic activity. Furthermore, neutrophil pseudopodia underwent alterations during the early stages of phagocytosis. The findings demonstrated that the biochemical profile of neutrophils is practically identical after phagocytosis of both types of quantum dots, but differs significantly from neutrophil metabolism after bacterial phagocytosis.

Influence of Magnetite Nanoparticles and Quantum Dots on the Expression of Reference Genes in Peripheral Blood Cells.

We studied the influence of magnetite nanoparticles (FeO•Fe2O3) and quantum dots (CdSe/ZnS coated with mercaptopropionic acid) on the expression of 5 common reference genes (BA, B2M, PPIA, UBC, and YWHAZ) in peripheral blood cells from 20 volunteers by reverse transcription PCR method. The stability of the expression of reference genes varied depending of the cells type and chemical structure of nanoparticles. The level of YWHAZ mRNA after exposure by nanoparticles demonstrated highest stability in lymphocytes, neutrophils, and monocytes. Stability of YWHAZ expression was confirmed by Western blotting. Our findings suggest that YWHAZ is the most suitable as the reference gene.

[CHARACTERIZATION OF THE DIFFERENCE IN THE MORPHOLOGY OF DETERGENT RESISTANT MEMBRANES DOMAINS ISOLATED FROM DIFFERENT CELL TYPES BY ATOMIC FORCE MICROSCOPY].

Planar raft and caveolae are specific membrane clusters with high concentration of cholesterol and lipids with saturated fatty acid. These clasters are resistant to detergents and are denoted as detergent resistant membranes domains (DRMs). Their morphology and size have been studied by atomic force microscopy. The size of planar rafts isolated by Librol from monocytes of healthy volunteers was 150.6 ± 68.6 nm--diameters and 5.7 ± 2.9 nm--height, the size of caveolae was 87.3 ± 46.1 nm--diameters and 9.4 ± 5.4 nm--height. Significant difference have been found morphology and size of DRMs isolated from monocytes of healthy volunteers and patients suffering from myocardial infarction as well as between DRMs isolated from endothelial cells. The study of time-dependent changes in the morphology of isolated planar rafts and caveolae has shown that they quickly aggregate during keeping. Therefore, to asses the actual size and morphology of the DRMS, they should be investigated immediately after isolation.

Bactericidal activity of titanium dioxide ultraviolet-induced films.

TiO2 films are used as a self-sterilization surface due to their property to form reactive oxygen species (ROS) when irradiated with ultraviolet light. These ROS attack bacteria and kill them. We present a new way to enhance the bactericidal activity of TiO2-films: formation of nanopores on the surface by four-beam high-power laser irradiation. Such surfaces have significantly higher antibacterial activity as compared to conventional TiO2 surfaces after 15 and 60min of UV irradiation. Study of the bacterial cell morphology by atomic force microscopy after 60min irradiation showed that Staphylococcus aureus 956 and Escherichia coli 321-5 undergo significant morphological changes. S. aureus assume atypical elongated shapes after UV treatment alone and swollen forms with protrusions after UV treatment on TiO2 surface. E. coli exhibit oval or round forms after UV treatment alone, and round forms with small protrusions, and destroyed cells after incubation under UV on the TiO2 film.

[Low doses of ionizing radiation-induced apoptotic nature of erythrocyte hemolysis].

It is established that exposure of the red blood cells of the rats to low doses of ionizing radiation (0.04; 0.08; 0.16; 0.25 and 0.33 mGr) leads to non-linear changes in the processes of lipid peroxidation in the membrane of erythrocytes, their electrophoretic mobility, osmotic resistance. In a dose range from 0.08 to 0.16 mGr with ionizing radiation apoptosis that determines a temporary slowing of the process of hemolysis and stabilization of erythrocytes that is confirmed by morphological changes in erythrocytes is most likely triggered.

Interactions of quantum dots with donor blood erythrocytes in vitro.

The effects of quantum dots CdSe/ZnS-mercaptopropionic acid, (CdSe/CdZnS)ZnS-polyT, and CdSeCdSZnS/polyT/SiO2-NH2 on human erythrocytes were studied. The nanomaterials reduced signifi cantly the erythrocyte sedimentation rate and modified the erythrocyte membrane resistance to induced (acid and hypo-osmotic) hemolysis. Evaluation of the erythrocyte morphology by atomic force microscopy in the control and after exposure to quantum dots showed significant differences in erythrocyte size and changes in their morphology as a result of exposure to the nanomaterials.

[Comparative morphofunctional description of planar rafts and caveolae].

Recently, redefining of the role of the membrane lipids and the formation of a new look at the morphology, organization and functioning of membranes occurred due to the study of specific membrane clusters--rafts. The present review summarizes the current data concerning the morphology, the biophysical and biochemical properties of rafts, describes the structure, form and basic functional microdomains marking proteins.

[Research of biocompatibility of nanoparticles with fluorescent domen Er/Yb in the neutrophilic granulocytes system].

Fluorescent tags are extensively used for the diagnostic, labeling and marking in vivo and in vitro systems. In this study, fluorescent nanoparticles with Er/Yb lightning center were tested on neutrophilic granulocytes. The main purpose was to idenfity possible toxic effect. The negative impact of fluorophores on the metabolism of neutrophilic and their enzyme systems, on the receptor-mediated cell responses and on the rigidity of cell membranes was shown. The viability of neutrophils (estimated with the use of propidium iodide) after 2 hours of incubation with the fluorescent nanoparticles in concentrations of 10(-4) and 10(-3) mM was 27.0 +/- 6.6 and 19.07 +/- 3.34 %, respectively.

[Photoinduced bactericidal activity of TiO2 films].

A decline in CFU of gram-positive and gram-negative bacteria on the surface of UV illuminated TiO2 films (wavelength of 380 nm) is shown. A 29, 45, and 47% decrease in bacterial viability of Staphylococcus aureus, Staphylococcus epidermidis, and Escherichia coli, respectively, was seen following a 12-min exposition. It was first discovered that the reuse of TiO2 films to test a bacterial suspension for viability removes UV-induced bactericidal activity. However, annealing of TiO2 at a temperature above 400 degrees C restores the photoinduced bactericidal activity to its initial state.

Modulation of oxygen-dependent and oxygen-independent metabolism of neutrophilic granulocytes by quantum points.

Inhibition of neutrophilic granulocyte metabolism under the effect of semiconductor quantum points was demonstrated. The status of the oxidative system was evaluated by the NBT test, nonoxidative status by the lysosomal cationic test. It was found that quantum points in a dose of 0.1 mg/ml irrespective of their core and composition of coating significantly inhibited oxygen-dependent and oxygen-independent metabolism of neutrophilic granulocytes.

[Differences in the functional activity of human neutrophilic granulocytes in their interactions with semiconductor quantum dots].

The uptake of quantum dots (QD-5 nm particles of CdSe/ZnS-mercaptoacetic acid) by human neutrophilic granulocytes was studied using the methods of scanning laser and scanning probe microscopy. The results show that the neutrophilic granulocytes may be subdivided into three subpopulations: (1) the cells with no uptake of QD (10.0 +/- 2.0%); (2) cells that accumulate QD in their volume (28.0 +/- 1.9%), and (3) cells, surrounded by a halo of QD (59.0 +/- 2.2%). The dispersion of these characteristics may suggest the differences in neutrophilic granulocyte plasma membrane permeability.

Study of morphology and rigidity of neutrophilic granulocyte membrane in the real time mode by scanning probe microscopy.

The rigidity of neutrophilic granulocyte membrane was determined: 2.1+/-0.7 kPa. Scanning in the contact mode did not modify cell morphology, while spectroscopy caused nonspecific swelling reaction and a 3-fold increase in cell volume. Spectroscopy had no effect on rigidity of neutrophilic granulocyte membrane.

[Scanning probe microscopy for the study of morphological parameters of neutrophilic granulocytes].

Morphological parameters of human blood neutrophilic granulocytes were studied by scanning probe microscopy. The basic morphological characteristics of the living (unfixed) and fixed cells were compared. It was found that using the method described, the dimensions of the cells changed substantially and significantly depending upon the mode of fixation applied. The methanol fixation allowed to demonstrate the internal structure of a cell, though it sharply deformed the object of study. After glutaraldehyde fixation cells possessed the morphological characteristics similar to those of the living cells, but the diameter and height of the fixed cells were again different from those of living cells. The resolution of a scanning probe microscope was higher when the fixed cells were studied, permitting the visualization of a detailed cell structure, including the nucleus and cytoplasmic granules (in particular, when methanol fixation was used). However, this method of study is unreliable for the determination of cell dimensions (diameter and height).