Polymorphonuclear granulocytes (neutrophils) release the reactive oxygen species (ROS) for destru... more Polymorphonuclear granulocytes (neutrophils) release the reactive oxygen species (ROS) for destruction of pathogens, providing quicker of an organism from infections and own defective of transformed cells. Reactive oxygen species are also potential carcinogens because they facilitate mutagenesis, tumor promotion and progression. Balance between these opposite influences is supported by coordinated interrelations in intracellular signaling systems. Tumor growth influence on the NADPH oxidase in peripheral innate immune cells is unclear. A solid cancer model was developed after an intramuscular injection of Ehrlich carcinoma cells into hind leg of NMRI strain mice. Intensity of the respiratory burst was estimated by luminol-dependent chemiluminescence technique. Transformation of inflammatory reaction was revealed during tumor growth: greater amounts of neutrophils were recruited into peritoneal cavity; sizes of the cells, their nuclei and granules were enlarged; the ratio of differen...
Parvalbumin (PA) is a Ca(2+)-binding protein of vertebrates massively expressed in tissues with h... more Parvalbumin (PA) is a Ca(2+)-binding protein of vertebrates massively expressed in tissues with high oxygen uptake and respectively elevated level of reactive oxygen species (ROS). To characterize antioxidant properties of PA, antioxidant capacity (AOC) of intact rat α-PA has been explored. ORAC, TEAC and hydrogen peroxide AOC assays evidence conformation-dependent oxidation of the PA. AOC value for the apo-PA 4-11-fold exceeds that for the Ca(2+)-loaded protein. Despite folded conformation of apo-PA, it has AOC equivalent to that of the proteolized protein. The most populated under resting conditions PA form, Mg(2+)-bound PA, has AOC similar to that of apo-PA. ROS-induced changes in absorption spectrum of PA evidence an oxidation of PA's phenylalanines in the ORAC assay. Sensitivity of PA oxidation to its conformation enabled characterization of its metal affinity and pH-dependent behavior: a transition with pKa of 7.6 has been revealed for the Ca(2+)-loaded PA. Since total AOC of PA under in vivo conditions may reach the level of reduced glutathione, we propose that PA might modulate intracellular redox equilibria and/or signaling in a calcium-dependent manner. We speculate that the oxidation-mediated damage of some of PA-GABAergic interneurons observed in schizophrenia is due to a decline in total AOC of the reduced glutathione-PA pair.
Detonation ND (nanodiamond) holds much promise for biological studies and medical applications. P... more Detonation ND (nanodiamond) holds much promise for biological studies and medical applications. Properties like size of
particles, inclination for modification of their surface and unambiguous biocompatibility are crucial. Of prime importance is
interaction between ND and immune cells, which supervise foreign intrusion into an organism and eliminate it. Neutrophils
are more reactive in inflammatory response implementing cytotoxical arsenal including ROS (reactive oxygen species). The
aim of the work was to estimate the ability of two ND samples (produced by Diamond Center and PlasmaChem) to keep
the vitality of neutrophils from the inflammatory site. The ability of cells to generate ROS in the presence of ND particles is
considered as indicating their biocompatibility. IR spectra and size of particles in the samples were characterized. Acid
modification of ND was carried out to get the luminescent form. In the biological aspect, ND demonstrated up or down
action, depending on the concentration, time and conditions of activation of cells. Weak action of ND in whole blood was
obtained possibly owing to the ND adsorbed plasma proteins, which mask active functional groups to interact with the cell
membrane. ND did not influence the viability of isolated inflammatory neutrophils in low and moderate concentrations and
suppressed it in high concentrations (>1 g/l). Addition of ND to the cell suspension initiated concentration-dependent
reaction to produce ROS similar to respiratory burst. ND up-regulated response to bacterial formylpeptide, but up- and
down-modified (low or high concentrations, accordingly) response to such bacterial agents as OZ (opsonized zymosan),
which neutrophils swallow up by oxygen-dependent phagocytosis. Localization of the particles on the cell surface as into
the cells was identified by monitoring the intrinsic fluorescence of oxidized ND. The various mechanisms that could account
for penetration of ND particles into the cell are discussed. Common conclusion concerns compatibility of ND with living
neutrophils from inflammatory site and their normal functioning for infection safeguard.
The effects of mixed dietary coenzyme Q9, α-tocopherol, and β-carotene on immune cell activity an... more The effects of mixed dietary coenzyme Q9, α-tocopherol, and β-carotene on immune cell activity and blood cytokine profile were studied in peritoneal macrophages, spleen lymphocytes, and blood plasma from mice with acute inflammation induced by lipopolysaccharide (LPS). The activity of each fat-soluble antioxidant was also investigated separately in several model systems, both in vivo and in vitro. NMRI male mice were fed a diet supplemented with fat-soluble antioxidants for 15 days prior to LPS injection. LPS-induced inflammation resulted in induction of cellular production of pro-inflammatory cytokines such as TNF-α, IL-1α, IL-1β, IL-2, IL-6, IFN-γ, and also IL-10, an anti-inflammatory cytokine, and subsequent accumulation of these cytokines in blood plasma. In animals fed the antioxidant-rich diet, the inflammatory response to LPS injection was significantly reduced. The production of anti-inflammatory cytokine IL-10 in response to toxic stress and its accumulation in plasma were not modified by the diet. In addition, the expression of the inducible form of heat-shock protein 70 in mice treated with endotoxin was reduced in the animals pretreated with the antioxidant-rich diet. We showed that the diet suppressed phosphorylation of NF-κB, I κB kinase and SAPK/JNK proteins, thereby preventing the activation of the NF-κB kinase and SAPK/JNK signaling pathways in LPS-treated mice. In this report we demonstrate the potential effectiveness of naturally occurring antioxidant nutrients in the reduction of the inflammatory response. Therefore, it may be possible to develop novel therapeutic combinations, containing coenzyme Q9, α-tocopherol, and β-carotene, which promote immune stimulation.
Bulletin of Experimental Biology and Medicine, 2011
Studies on BALB/c mice with tumors of different immunogenic activity (nonimmunogenic J774, WEHI 1... more Studies on BALB/c mice with tumors of different immunogenic activity (nonimmunogenic J774, WEHI 164 and immunogenic NS0) have showed that the development of a tumor is associated with changes in the neutrophil morphology and functions: the counts and size of the cells migrating to the focus increase and their capacity to produce active oxygen species is changed.
Biochemistry (moscow) Supplement Series A: Membrane and Cell Biology, 2007
Endotoxic shock is a dangerous complication of infection caused by gram-negative bacteria. Search... more Endotoxic shock is a dangerous complication of infection caused by gram-negative bacteria. Searching for agents capable to block the effects of endotoxins is a fundamental scientific and medical problem. Here we studied the effects of neutrophil priming with non-toxic lipopolysaccharide from Rhodobacter capsulatus (LPSRb. caps. ) and toxic LPS from Escherichia coli (LPSE. coli ) on the respiratory burst evoked in neutrophils by opsonized E. coli. We found that preincubation of neutrophils with each of the LPS increased ROS production by neutrophils as compared to non-primed neutrophils. Subsequent incubation of neutrophils with LPSRb. caps. and then with LPSE. coli practically abolished the effects of both endotoxins.
Caspase activation and degradation of deoxyribonucleic acid (DNA) damage response factors occur d... more Caspase activation and degradation of deoxyribonucleic acid (DNA) damage response factors occur during in vitro T-cell proliferation, and an increased frequency of hypoxanthine-guanine phosphoribosyltransferase (HPRT)-negative variants have been reported in conditions associated with in vivo T-cell proliferation. We have applied two human somatic cell mutation reporter assays, for the HPRT and phosphatidylinositol glycan class A (PIG-A) genes, to human T cells activated in vitro with anti-CD3 and anti-CD28. We demonstrate proliferation throughout 6 weeks of cultivation, and find that the frequency of variant cells phenotypically negative for HPRT and PIG-A, respectively, increases from 10−5 up to 10−3–10−2. We also report preliminary evidence for low-density CpG methylation in the HPRT promoter suggesting that epigenetic modification may contribute to this markedly heightened rate of gene inactivation.
Bulletin of Experimental Biology and Medicine, 2006
We carried out a comparative clinical and immunological examination of newborns whose mothers wer... more We carried out a comparative clinical and immunological examination of newborns whose mothers were at risk of infectious inflammatory diseases. Umbilical blood cell phenotype was evaluated by flow cytofluorometry. ROS level was evaluated by chemiluminescence intensity. Spontaneous production of ROS and phagocytic activity of cells in the whole umbilical blood was reduced in newborns born after complicated pregnancy. Low immunoregulatory index indicating changed CD4+/CD8+ ratio and low percentage of natural killer cells were observed in children with manifestations of bacterial infection. ROS production by isolated granulocytes and the effects of PI3K and p38 MAPK (kinases involved in the regulation of activity of NADPH oxidase responsible for the production of ROS) in the risk group infants differed from the corresponding parameters in the control group. The results indicate shifts in the phagocytosis system, immune status, and the receptor-conjugated regulatory systems of ROS generation by granulocytes in newborns at risk of infectious inflammatory diseases.
Bulletin of Experimental Biology and Medicine, 2005
Production of reactive oxygen species in unfractionated peripheral blood increased in parturient ... more Production of reactive oxygen species in unfractionated peripheral blood increased in parturient women without postpartum infectious complications and patients with postpartum endometritis. The control group included nonpregnant women with normal reproductive function. Intergroup differences were revealed in the degree of respiratory burst activation with opsonized zymosan and response of isolated granulocytes to chemotactic peptide N-formyl-Met-Leu-Phen (1 µM). Production of reactive oxygen species tended to normal after therapy. We studied the effects of a specific mitogen-activated protein kinase p38MAPK inhibitor and inhibitors of tyrosine protein phosphatases and phosphatidylinositol-3-kinase. The role of p38MAPK in reactive oxygen species generation by cells changes significantly in parturient women.
The effect of ionized air containing negatively charged ions at a concentration of 320000–350000 ... more The effect of ionized air containing negatively charged ions at a concentration of 320000–350000 ions/cm3 inhaled by rats was studied. It was demonstrated that the inhalation of negative air ions for 60 min activated the secretion of goblet cells without impairing the tracheal mucosa and changing the protein profile of bronchoalveolar lavage. It was also found that the level of spontaneous production of reactive oxygen species by unfractionated blood cells increased after the action of negative air ions in both males and females. However, the intensity of their generation induced by opsonized zymosan increased only in females. Different sensitivities of the female and male blood antioxidant enzymes—superoxide dismutase and glutathione reductase—to negative air ions were observed. These results allow the effect of negative air ions on the respiratory organs and blood to be interpreted as priming and weak activation via a direct action on the mucosa of primary target respiratory organs and then on the blood.
Bulletin of Experimental Biology and Medicine, 2003
Generation of active oxygen forms by blood granulocytes was studied in women with a history of ha... more Generation of active oxygen forms by blood granulocytes was studied in women with a history of habitual abortions (2-3 spontaneous abortions in the first trimester, undeveloped pregnancies). The level of spontaneous luminol-dependent chemiluminescence of nonfractionated peripheral blood was increased in this patient population (study group) in comparison with women with normal reproductive function (reference group). The two groups differed by the level of activation of respiratory burst induced by opsonized zymosan and by activity of isolated granulocytes in response to chemotactic peptide N-formyl-methionyl-leucyl-phenylalanine (1-50 μM). Differences in the effects of inhibitor of tyrosine protein kinases and protein phosphatases and inhibitor of mitogen-activated proteinkinase p38 MAPK were detected. The results attest to predisposition to oxidative stress and poor cytotoxic functions of granulocytes in women with habitual abortions, which can be due to specific features of regulation of oxidase activity by tyrosine protein kinases and protein phosphatases and by p38 MAPK.
Polymorphonuclear granulocytes (neutrophils) release the reactive oxygen species (ROS) for destru... more Polymorphonuclear granulocytes (neutrophils) release the reactive oxygen species (ROS) for destruction of pathogens, providing quicker of an organism from infections and own defective of transformed cells. Reactive oxygen species are also potential carcinogens because they facilitate mutagenesis, tumor promotion and progression. Balance between these opposite influences is supported by coordinated interrelations in intracellular signaling systems. Tumor growth influence on the NADPH oxidase in peripheral innate immune cells is unclear. A solid cancer model was developed after an intramuscular injection of Ehrlich carcinoma cells into hind leg of NMRI strain mice. Intensity of the respiratory burst was estimated by luminol-dependent chemiluminescence technique. Transformation of inflammatory reaction was revealed during tumor growth: greater amounts of neutrophils were recruited into peritoneal cavity; sizes of the cells, their nuclei and granules were enlarged; the ratio of differen...
Parvalbumin (PA) is a Ca(2+)-binding protein of vertebrates massively expressed in tissues with h... more Parvalbumin (PA) is a Ca(2+)-binding protein of vertebrates massively expressed in tissues with high oxygen uptake and respectively elevated level of reactive oxygen species (ROS). To characterize antioxidant properties of PA, antioxidant capacity (AOC) of intact rat α-PA has been explored. ORAC, TEAC and hydrogen peroxide AOC assays evidence conformation-dependent oxidation of the PA. AOC value for the apo-PA 4-11-fold exceeds that for the Ca(2+)-loaded protein. Despite folded conformation of apo-PA, it has AOC equivalent to that of the proteolized protein. The most populated under resting conditions PA form, Mg(2+)-bound PA, has AOC similar to that of apo-PA. ROS-induced changes in absorption spectrum of PA evidence an oxidation of PA's phenylalanines in the ORAC assay. Sensitivity of PA oxidation to its conformation enabled characterization of its metal affinity and pH-dependent behavior: a transition with pKa of 7.6 has been revealed for the Ca(2+)-loaded PA. Since total AOC of PA under in vivo conditions may reach the level of reduced glutathione, we propose that PA might modulate intracellular redox equilibria and/or signaling in a calcium-dependent manner. We speculate that the oxidation-mediated damage of some of PA-GABAergic interneurons observed in schizophrenia is due to a decline in total AOC of the reduced glutathione-PA pair.
Detonation ND (nanodiamond) holds much promise for biological studies and medical applications. P... more Detonation ND (nanodiamond) holds much promise for biological studies and medical applications. Properties like size of
particles, inclination for modification of their surface and unambiguous biocompatibility are crucial. Of prime importance is
interaction between ND and immune cells, which supervise foreign intrusion into an organism and eliminate it. Neutrophils
are more reactive in inflammatory response implementing cytotoxical arsenal including ROS (reactive oxygen species). The
aim of the work was to estimate the ability of two ND samples (produced by Diamond Center and PlasmaChem) to keep
the vitality of neutrophils from the inflammatory site. The ability of cells to generate ROS in the presence of ND particles is
considered as indicating their biocompatibility. IR spectra and size of particles in the samples were characterized. Acid
modification of ND was carried out to get the luminescent form. In the biological aspect, ND demonstrated up or down
action, depending on the concentration, time and conditions of activation of cells. Weak action of ND in whole blood was
obtained possibly owing to the ND adsorbed plasma proteins, which mask active functional groups to interact with the cell
membrane. ND did not influence the viability of isolated inflammatory neutrophils in low and moderate concentrations and
suppressed it in high concentrations (>1 g/l). Addition of ND to the cell suspension initiated concentration-dependent
reaction to produce ROS similar to respiratory burst. ND up-regulated response to bacterial formylpeptide, but up- and
down-modified (low or high concentrations, accordingly) response to such bacterial agents as OZ (opsonized zymosan),
which neutrophils swallow up by oxygen-dependent phagocytosis. Localization of the particles on the cell surface as into
the cells was identified by monitoring the intrinsic fluorescence of oxidized ND. The various mechanisms that could account
for penetration of ND particles into the cell are discussed. Common conclusion concerns compatibility of ND with living
neutrophils from inflammatory site and their normal functioning for infection safeguard.
The effects of mixed dietary coenzyme Q9, α-tocopherol, and β-carotene on immune cell activity an... more The effects of mixed dietary coenzyme Q9, α-tocopherol, and β-carotene on immune cell activity and blood cytokine profile were studied in peritoneal macrophages, spleen lymphocytes, and blood plasma from mice with acute inflammation induced by lipopolysaccharide (LPS). The activity of each fat-soluble antioxidant was also investigated separately in several model systems, both in vivo and in vitro. NMRI male mice were fed a diet supplemented with fat-soluble antioxidants for 15 days prior to LPS injection. LPS-induced inflammation resulted in induction of cellular production of pro-inflammatory cytokines such as TNF-α, IL-1α, IL-1β, IL-2, IL-6, IFN-γ, and also IL-10, an anti-inflammatory cytokine, and subsequent accumulation of these cytokines in blood plasma. In animals fed the antioxidant-rich diet, the inflammatory response to LPS injection was significantly reduced. The production of anti-inflammatory cytokine IL-10 in response to toxic stress and its accumulation in plasma were not modified by the diet. In addition, the expression of the inducible form of heat-shock protein 70 in mice treated with endotoxin was reduced in the animals pretreated with the antioxidant-rich diet. We showed that the diet suppressed phosphorylation of NF-κB, I κB kinase and SAPK/JNK proteins, thereby preventing the activation of the NF-κB kinase and SAPK/JNK signaling pathways in LPS-treated mice. In this report we demonstrate the potential effectiveness of naturally occurring antioxidant nutrients in the reduction of the inflammatory response. Therefore, it may be possible to develop novel therapeutic combinations, containing coenzyme Q9, α-tocopherol, and β-carotene, which promote immune stimulation.
Bulletin of Experimental Biology and Medicine, 2011
Studies on BALB/c mice with tumors of different immunogenic activity (nonimmunogenic J774, WEHI 1... more Studies on BALB/c mice with tumors of different immunogenic activity (nonimmunogenic J774, WEHI 164 and immunogenic NS0) have showed that the development of a tumor is associated with changes in the neutrophil morphology and functions: the counts and size of the cells migrating to the focus increase and their capacity to produce active oxygen species is changed.
Biochemistry (moscow) Supplement Series A: Membrane and Cell Biology, 2007
Endotoxic shock is a dangerous complication of infection caused by gram-negative bacteria. Search... more Endotoxic shock is a dangerous complication of infection caused by gram-negative bacteria. Searching for agents capable to block the effects of endotoxins is a fundamental scientific and medical problem. Here we studied the effects of neutrophil priming with non-toxic lipopolysaccharide from Rhodobacter capsulatus (LPSRb. caps. ) and toxic LPS from Escherichia coli (LPSE. coli ) on the respiratory burst evoked in neutrophils by opsonized E. coli. We found that preincubation of neutrophils with each of the LPS increased ROS production by neutrophils as compared to non-primed neutrophils. Subsequent incubation of neutrophils with LPSRb. caps. and then with LPSE. coli practically abolished the effects of both endotoxins.
Caspase activation and degradation of deoxyribonucleic acid (DNA) damage response factors occur d... more Caspase activation and degradation of deoxyribonucleic acid (DNA) damage response factors occur during in vitro T-cell proliferation, and an increased frequency of hypoxanthine-guanine phosphoribosyltransferase (HPRT)-negative variants have been reported in conditions associated with in vivo T-cell proliferation. We have applied two human somatic cell mutation reporter assays, for the HPRT and phosphatidylinositol glycan class A (PIG-A) genes, to human T cells activated in vitro with anti-CD3 and anti-CD28. We demonstrate proliferation throughout 6 weeks of cultivation, and find that the frequency of variant cells phenotypically negative for HPRT and PIG-A, respectively, increases from 10−5 up to 10−3–10−2. We also report preliminary evidence for low-density CpG methylation in the HPRT promoter suggesting that epigenetic modification may contribute to this markedly heightened rate of gene inactivation.
Bulletin of Experimental Biology and Medicine, 2006
We carried out a comparative clinical and immunological examination of newborns whose mothers wer... more We carried out a comparative clinical and immunological examination of newborns whose mothers were at risk of infectious inflammatory diseases. Umbilical blood cell phenotype was evaluated by flow cytofluorometry. ROS level was evaluated by chemiluminescence intensity. Spontaneous production of ROS and phagocytic activity of cells in the whole umbilical blood was reduced in newborns born after complicated pregnancy. Low immunoregulatory index indicating changed CD4+/CD8+ ratio and low percentage of natural killer cells were observed in children with manifestations of bacterial infection. ROS production by isolated granulocytes and the effects of PI3K and p38 MAPK (kinases involved in the regulation of activity of NADPH oxidase responsible for the production of ROS) in the risk group infants differed from the corresponding parameters in the control group. The results indicate shifts in the phagocytosis system, immune status, and the receptor-conjugated regulatory systems of ROS generation by granulocytes in newborns at risk of infectious inflammatory diseases.
Bulletin of Experimental Biology and Medicine, 2005
Production of reactive oxygen species in unfractionated peripheral blood increased in parturient ... more Production of reactive oxygen species in unfractionated peripheral blood increased in parturient women without postpartum infectious complications and patients with postpartum endometritis. The control group included nonpregnant women with normal reproductive function. Intergroup differences were revealed in the degree of respiratory burst activation with opsonized zymosan and response of isolated granulocytes to chemotactic peptide N-formyl-Met-Leu-Phen (1 µM). Production of reactive oxygen species tended to normal after therapy. We studied the effects of a specific mitogen-activated protein kinase p38MAPK inhibitor and inhibitors of tyrosine protein phosphatases and phosphatidylinositol-3-kinase. The role of p38MAPK in reactive oxygen species generation by cells changes significantly in parturient women.
The effect of ionized air containing negatively charged ions at a concentration of 320000–350000 ... more The effect of ionized air containing negatively charged ions at a concentration of 320000–350000 ions/cm3 inhaled by rats was studied. It was demonstrated that the inhalation of negative air ions for 60 min activated the secretion of goblet cells without impairing the tracheal mucosa and changing the protein profile of bronchoalveolar lavage. It was also found that the level of spontaneous production of reactive oxygen species by unfractionated blood cells increased after the action of negative air ions in both males and females. However, the intensity of their generation induced by opsonized zymosan increased only in females. Different sensitivities of the female and male blood antioxidant enzymes—superoxide dismutase and glutathione reductase—to negative air ions were observed. These results allow the effect of negative air ions on the respiratory organs and blood to be interpreted as priming and weak activation via a direct action on the mucosa of primary target respiratory organs and then on the blood.
Bulletin of Experimental Biology and Medicine, 2003
Generation of active oxygen forms by blood granulocytes was studied in women with a history of ha... more Generation of active oxygen forms by blood granulocytes was studied in women with a history of habitual abortions (2-3 spontaneous abortions in the first trimester, undeveloped pregnancies). The level of spontaneous luminol-dependent chemiluminescence of nonfractionated peripheral blood was increased in this patient population (study group) in comparison with women with normal reproductive function (reference group). The two groups differed by the level of activation of respiratory burst induced by opsonized zymosan and by activity of isolated granulocytes in response to chemotactic peptide N-formyl-methionyl-leucyl-phenylalanine (1-50 μM). Differences in the effects of inhibitor of tyrosine protein kinases and protein phosphatases and inhibitor of mitogen-activated proteinkinase p38 MAPK were detected. The results attest to predisposition to oxidative stress and poor cytotoxic functions of granulocytes in women with habitual abortions, which can be due to specific features of regulation of oxidase activity by tyrosine protein kinases and protein phosphatases and by p38 MAPK.
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Papers by Nadezhda Avkhacheva
particles, inclination for modification of their surface and unambiguous biocompatibility are crucial. Of prime importance is
interaction between ND and immune cells, which supervise foreign intrusion into an organism and eliminate it. Neutrophils
are more reactive in inflammatory response implementing cytotoxical arsenal including ROS (reactive oxygen species). The
aim of the work was to estimate the ability of two ND samples (produced by Diamond Center and PlasmaChem) to keep
the vitality of neutrophils from the inflammatory site. The ability of cells to generate ROS in the presence of ND particles is
considered as indicating their biocompatibility. IR spectra and size of particles in the samples were characterized. Acid
modification of ND was carried out to get the luminescent form. In the biological aspect, ND demonstrated up or down
action, depending on the concentration, time and conditions of activation of cells. Weak action of ND in whole blood was
obtained possibly owing to the ND adsorbed plasma proteins, which mask active functional groups to interact with the cell
membrane. ND did not influence the viability of isolated inflammatory neutrophils in low and moderate concentrations and
suppressed it in high concentrations (>1 g/l). Addition of ND to the cell suspension initiated concentration-dependent
reaction to produce ROS similar to respiratory burst. ND up-regulated response to bacterial formylpeptide, but up- and
down-modified (low or high concentrations, accordingly) response to such bacterial agents as OZ (opsonized zymosan),
which neutrophils swallow up by oxygen-dependent phagocytosis. Localization of the particles on the cell surface as into
the cells was identified by monitoring the intrinsic fluorescence of oxidized ND. The various mechanisms that could account
for penetration of ND particles into the cell are discussed. Common conclusion concerns compatibility of ND with living
neutrophils from inflammatory site and their normal functioning for infection safeguard.
particles, inclination for modification of their surface and unambiguous biocompatibility are crucial. Of prime importance is
interaction between ND and immune cells, which supervise foreign intrusion into an organism and eliminate it. Neutrophils
are more reactive in inflammatory response implementing cytotoxical arsenal including ROS (reactive oxygen species). The
aim of the work was to estimate the ability of two ND samples (produced by Diamond Center and PlasmaChem) to keep
the vitality of neutrophils from the inflammatory site. The ability of cells to generate ROS in the presence of ND particles is
considered as indicating their biocompatibility. IR spectra and size of particles in the samples were characterized. Acid
modification of ND was carried out to get the luminescent form. In the biological aspect, ND demonstrated up or down
action, depending on the concentration, time and conditions of activation of cells. Weak action of ND in whole blood was
obtained possibly owing to the ND adsorbed plasma proteins, which mask active functional groups to interact with the cell
membrane. ND did not influence the viability of isolated inflammatory neutrophils in low and moderate concentrations and
suppressed it in high concentrations (>1 g/l). Addition of ND to the cell suspension initiated concentration-dependent
reaction to produce ROS similar to respiratory burst. ND up-regulated response to bacterial formylpeptide, but up- and
down-modified (low or high concentrations, accordingly) response to such bacterial agents as OZ (opsonized zymosan),
which neutrophils swallow up by oxygen-dependent phagocytosis. Localization of the particles on the cell surface as into
the cells was identified by monitoring the intrinsic fluorescence of oxidized ND. The various mechanisms that could account
for penetration of ND particles into the cell are discussed. Common conclusion concerns compatibility of ND with living
neutrophils from inflammatory site and their normal functioning for infection safeguard.