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Sample records for human erythrocytes lymphocytes

  1. Lysophosphatidylcholine hydrolases of human erythrocytes, lymphocytes, and brain: Sensitive targets of conserved specificity for organophosphorus delayed neurotoxicants

    Vose, Sarah C.; Holland, Nina T.; Eskenazi, Brenda; Casida, John E.

    2007-01-01

    Brain neuropathy target esterase (NTE), associated with organophosphorus (OP)-induced delayed neuropathy, has the same OP inhibitor sensitivity and specificity profiles assayed in the classical way (paraoxon-resistant, mipafox-sensitive hydrolysis of phenyl valerate) or with lysophosphatidylcholine (LysoPC) as the substrate. Extending our earlier observation with mice, we now examine human erythrocyte, lymphocyte, and brain LysoPC hydrolases as possible sensitive targets for OP delayed neurotoxicants and insecticides. Inhibitor profiling of human erythrocytes and lymphocytes gave the surprising result of essentially the same pattern as with brain. Human erythrocyte LysoPC hydrolases are highly sensitive to OP delayed neurotoxicants, with in vitro IC 50 values of 0.13-85 nM for longer alkyl analogs, and poorly sensitive to the current OP insecticides. In agricultural workers, erythrocyte LysoPC hydrolyzing activities are similar for newborn children and their mothers and do not vary with paraoxonase status but have high intersample variation that limits their use as a biomarker. Mouse erythrocyte LysoPC hydrolase activity is also of low sensitivity in vitro and in vivo to the OP insecticides whereas the delayed neurotoxicant ethyl n-octylphosphonyl fluoride inhibits activity in vivo at 1-3 mg/kg. Overall, inhibition of blood LysoPC hydrolases is as good as inhibition of brain NTE as a predictor of OP inducers of delayed neuropathy. NTE and lysophospholipases (LysoPLAs) both hydrolyze LysoPC, yet they are in distinct enzyme families with no sequence homology and very different catalytic sites. The relative contributions of NTE and LysoPLAs to LysoPC hydrolysis and clearance from erythrocytes, lymphocytes, and brain remain to be defined

  2. Diminution of Oxidative Damage to Human Erythrocytes and Lymphocytes by Creatine: Possible Role of Creatine in Blood.

    Neha Qasim

    Full Text Available Creatine (Cr is naturally produced in the body and stored in muscles where it is involved in energy generation. It is widely used, especially by athletes, as a staple supplement for improving physical performance. Recent reports have shown that Cr displays antioxidant activity which could explain its beneficial cellular effects. We have evaluated the ability of Cr to protect human erythrocytes and lymphocytes against oxidative damage. Erythrocytes were challenged with model oxidants, 2, 2'-azobis(2-amidinopropane dihydrochloride (AAPH and hydrogen peroxide (H2O2 in the presence and absence of Cr. Incubation of erythrocytes with oxidant alone increased hemolysis, methemoglobin levels, lipid peroxidation and protein carbonyl content. This was accompanied by decrease in glutathione levels. Antioxidant enzymes and antioxidant power of the cell were compromised while the activity of membrane bound enzyme was lowered. This suggests induction of oxidative stress in erythrocytes by AAPH and H2O2. However, Cr protected the erythrocytes by ameliorating the AAPH and H2O2 induced changes in these parameters. This protective effect was confirmed by electron microscopic analysis which showed that oxidant-induced cell damage was attenuated by Cr. No cellular alterations were induced by Cr alone even at 20 mM, the highest concentration used. Creatinine, a by-product of Cr metabolism, was also shown to exert protective effects, although it was slightly less effective than Cr. Human lymphocytes were similarly treated with H2O2 in absence and presence of different concentrations of Cr. Lymphocytes incubated with oxidant alone had alterations in various biochemical and antioxidant parameters including decrease in cell viability and induction of DNA damage. The presence of Cr attenuated all these H2O2-induced changes in lymphocytes. Thus, Cr can function as a blood antioxidant, protecting cells from oxidative damage, genotoxicity and can potentially increase their

  3. [Ceruloplasmin receptor on human erythrocytes].

    Saenko, E L; Basevich, V V; Iaropolov, A I

    1988-08-01

    The structural fragments of the human ceruloplasmin (CP) molecule and of erythrocyte receptors which provide for the specific interaction of CP with erythrocytes were identified, and their properties were investigated. The interaction of CP with erythrocytes, both intact and treated with neuroaminidase and proteolytic enzymes (trypsin, chymotrypsin, papaine, pronase E) is described. Experiments with CP reception were performed at 4 degrees C, using [125I]CP and [125I]asialo-CP. The parameters of binding were determined in Scatchard plots. It was demonstrated that the specific binding of CP to erythrocyte receptors is determined by its interaction with two structural sites of the carbohydrate moiety of the CP molecule, i.e., the terminal residues of sialic acids and a site, (formula; see text) located at a large distance from the chain terminus.

  4. Evidence for coordinate genetic control of Na,K pump density in erythrocytes and lymphocytes

    DeLuise, M.; Flier, J.S.

    1985-01-01

    The erythrocyte is widely used as a model cell for studies of the Na,K pump in health and disease. However, little is known about the factors that control the number of Na,K pumps expressed on the erythrocytes of a given individual, nor about the extent to which erythrocytes can be used to validly assess the pump density on other cell types. In this report, the authors have compared the interindividual variance of Na,K pump density in erythrocytes of unrelated individuals to that seen with identical twins. Unlike unrelated individuals, in whom pump parameters, i.e., ouabain binding sites, 86 Rb uptake, and cell Na concentration vary widely, identical twin pairs showed no significant intrapair variation for these values. Thus, a role for genetic factors is suggested. In addition, the authors established and validated a method for determining Na,K pump density and pump-mediated 86 Rb uptake in human peripheral lymphocytes. Using this method, they show that whereas Na,K pump density differs markedly between erythrocytes (mean of 285 sites per cell) and lymphocytes (mean 40,600 sites per cell), there is a strong and highly significant correlation (r = 0.79, P less than 0.001) between the pump density in these cell types in any given individual. Taken together, these studies suggest that genetic factors are important determinants of Na,K pump expression, and that pump density appears to be coordinately regulated in two cell types in healthy individuals

  5. Specific binding of beta-endorphin to normal human erythrocytes

    Chenet, B.; Hollis, V. Jr.; Kang, Y.; Simpkins, C.

    1986-03-05

    Beta-endorphin (BE) exhibits peripheral functions which may not be mediated by interactions with receptors in the brain. Recent studies have demonstrated binding of BE to both opioid and non-opioid receptors on lymphocytes and monocytes. Abood has reported specific binding of /sup 3/H-dihydromorphine in erythrocytes. Using 5 x 10/sup -11/M /sup 125/I-beta-endorphin and 10/sup -5/M unlabeled BE, they have detected 50% specific binding to human erythrocytes. This finding is supported by results from immunoelectron microscopy using rabbit anti-BE antibody and biotinylated secondary antibody with avidin-biotin complexes horseradish peroxidase. Binding is clearly observed and is confined to only one side of the cells. Conclusions: (1) BE binding to human erythrocytes was demonstrated by radioreceptor assay and immunoelectron microscopy, and (2) BE binding sites exist on only one side of the cells.

  6. Separation and properties of EA-rosette-forming lymphocytes in humans

    van Oers, M. H.; Zeijlemaker, W. P.; Schellekens, P. T.

    1977-01-01

    Human peripheral blood lymphocytes were separated into subpopulations enriched or depleted with respect to B lymphocytes (Ig-bearing cells), T lymphocytes, (cell forming rosettes with sheep erythrocytes: E-RFC) and Fc receptor-bearing lymphocytes (EA-RFC). From the distributions and recoveries of

  7. Induction of transient radioresistance in human erythrocytes

    Krokosz, Anita; Szweda-Lewandowska, Zofia

    2006-01-01

    Human erythrocytes suspended in an isotonic Na-phosphate buffer, pH 7.4 (hematocrit of 2%), were irradiated with γ-rays with single and split doses under air or N 2 O in order to determine the physicochemical changes caused by the dose inducing an increase in resistance to radiation-induced hemolysis. The obtained results showed that under the applied irradiation conditions, the dose of 0.4 kGy induced changes in erythrocytes, which were responsible for temporary resistance of erythrocytes to hemolysis. We concluded that the observed resistance is caused mainly by the structural changes in proteins

  8. Clofazimine Induced Suicidal Death of Human Erythrocytes

    Arbace Officioso

    2015-08-01

    Full Text Available Background/Aims: The antimycobacterial riminophenazine clofazimine has previously been shown to up-regulate cellular phospholipase A2 and to induce apoptosis. In erythrocytes phospholipase A2 stimulates eryptosis, the suicidal erythrocyte death characterized by cell shrinkage and cell membrane scrambling with phosphatidylserine translocation to the erythrocyte surface. Phospholipase A2 is in part effective by fostering formation of prostaglandin E2, which triggers Ca2+ entry. Stimulators of Ca2+ entry and eryptosis further include oxidative stress and energy depletion. The present study tested, whether and how clofazimine induces eryptosis. Methods: Phosphatidylserine exposure at the cell surface was estimated from annexin V binding, cell volume from forward scatter, hemolysis from hemoglobin release, cytosolic Ca2+ activity ([Ca2+]i from Fluo3-fluorescence, reactive oxygen species (ROS from 2′, 7′-dichlorodihydrofluorescein diacetate (DCFDA fluorescence, and cytosolic ATP level utilizing a luciferin-luciferase assay kit. Results: A 24-48 hours exposure of human erythrocytes to clofazimine (≥1.5 µg/ml significantly increased the percentage of annexin-V-binding cells without appreciably modifying forward scatter. Clofazimine significantly increased [Ca2+]i, significantly decreased cytosolic ATP, but did not significantly modify ROS. The effect of clofazimine on annexin-V-binding was significantly blunted, but not fully abolished by removal of extracellular Ca2+, and by phospholipase A2 inhibitor quinacrine (25 µM. Clofazimine further augmented the effect of Ca2+ ionophore ionomycin (0.1 µM on eryptosis. The clofazimine induced annexin-V-binding was, however, completely abrogated by combined Ca2+ removal and addition of quinacrine. Conclusion: Clofazimine stimulates phospholipid scrambling of the erythrocyte cell membrane, an effect in part dependent on entry of extracellular Ca2+, paralleled by cellular energy depletion and sensitive to

  9. Fucoxanthin Induced Suicidal Death of Human Erythrocytes

    Marilena Briglia

    2015-12-01

    Full Text Available Background/Aims: Fucoxanthin, a carotenoid isolated from brown seaweeds, induces suicidal death or apoptosis of tumor cells and is thus considered for the treatment or prevention of malignancy. In analogy to apoptosis of nucleated cell, erythrocytes may enter eryptosis, the suicidal death characterized by cell shrinkage and cell membrane scrambling with phosphatidylserine translocation to the erythrocyte surface. Triggers of eryptosis include Ca2+ entry with increase of cytosolic Ca2+ activity ([Ca2+]i, oxidative stress and activation of p38 kinase or protein kinase C. The present study explored, whether and how fucoxanthin induces eryptosis. Methods: Phosphatidylserine exposure at the cell surface was estimated from annexin-V-binding, cell volume from forward scatter, hemolysis from hemoglobin release, [Ca2+]i from Fluo3-fluorescence, and abundance of reactive oxygen species (ROS from DCFDA dependent fluorescence and lipid peroxidation using BODIPY fluoresence. Results: A 48 hours exposure of human erythrocytes to fucoxanthin significantly increased the percentage of annexin-V-binding cells (≥ 50 µM, significantly decreased average forward scatter (≥ 25 µM, significantly increased hemolysis (≥ 25 µM, significantly increased Fluo3-fluorescence (≥ 50 µM, significantly increased lipid peroxidation, but did not significantly modify DCFDA fluorescence. The effect of fucoxanthin on annexin-V-binding was significantly blunted, but not abolished by removal of extracellular Ca2+, and was insensitive to p38 kinase inhibitor skepinone (2 µM and to protein kinase C inhibitor calphostin (100 nM. Conclusion: Fucoxanthin triggers cell shrinkage and phospholipid scrambling of the erythrocyte cell membrane, an effect in part due to stimulation of Ca2+ entry.

  10. Monoclonal antibodies to antigens on human neutrophils, activated T lymphocytes, and acute leukemia blast cells

    Miterev, G.Yu.; Burova, G.F.; Puzhitskaya, M.S.; Danilevich, S.V.; Bulycheva, T.I.

    1987-01-01

    The authors describe the production of two mouse hybridomas secreting monoclonal antibodies to antigenic determinants of the surface membranes of human neutrophils, activated T lymphocytes, and acute leukemic blast cells. The degree of lymphocyte stimulation was estimated from incorporation of 3 H-thymidine with parallel microculture. Monoclonal antibodies of supernatants of hybridoma cultures shown here reacted in both immunofluorescence test and cytotoxicity test with surface membrane antigens on the majority of neutrophils and PHA-activated peripheral blood lymphocytes from healthy subjects, but did not give positive reactions with unactivated lymphocytes, adherent monocytes, erythrocytes, and alloantigen-stimulated lymphocytes

  11. Monoclonal antibodies to antigens on human neutrophils, activated T lymphocytes, and acute leukemia blast cells

    Miterev, G.Yu.; Burova, G.F.; Puzhitskaya, M.S.; Danilevich, S.V.; Bulycheva, T.I.

    1987-11-01

    The authors describe the production of two mouse hybridomas secreting monoclonal antibodies to antigenic determinants of the surface membranes of human neutrophils, activated T lymphocytes, and acute leukemic blast cells. The degree of lymphocyte stimulation was estimated from incorporation of /sup 3/H-thymidine with parallel microculture. Monoclonal antibodies of supernatants of hybridoma cultures shown here reacted in both immunofluorescence test and cytotoxicity test with surface membrane antigens on the majority of neutrophils and PHA-activated peripheral blood lymphocytes from healthy subjects, but did not give positive reactions with unactivated lymphocytes, adherent monocytes, erythrocytes, and alloantigen-stimulated lymphocytes.

  12. Erythrocyte metallothionein as an index of zinc status in humans

    Grider, A.; Bailey, L.B.; Cousins, R.J.

    1990-01-01

    Metallothionein concentrations in erythrocyte lysates derived from human subjects were measured by an ELISA procedure. IgG obtained from serum of sheep injected with human metallothionein 1 was used in this competitive assay. Subjects were fed a semipurified zinc-deficient diet for an 8-day depletion period after 3 days of acclimation. Fasting plasma zinc concentrations were reduced ∼7%. Metallothionein in the erythrocyte lysates was significantly decreased to 59% of the initial level by the end of the depletion period. Supplementation of these depleted subjects with zinc did not increase erythrocyte metallothionein levels within 24 hr. Daily supplementation of control subjects with zinc increased erythrocyte metallothionein to a 7-fold maximum within 7 days. These levels were reduced by 61% within 14 days after zinc supplementation was terminated. Incubation of rat [ 35 S]metallothionein with human erythrocyte lysate showed a time-dependent increase in 35 S soluble in 20% trichloroacetic acid, indicating degradation of the labeled protein, presumably via protease activity in the lysate. It is proposed that zinc supplementation induces erythrocyte metallothionein during erythropoiesis and that low zinc intake decreases synthesis and/or accelerates degradation of the protein in reticulocytes/erythrocytes. Metallothionein levels in erythrocytes may provide a useful index upon which to assess zinc status in humans

  13. Spin labelling of human erythrocytes with nitroxide radicals

    Chagalj, C.; DePaoli, T.C.P.; Hager, A.A.; Palaoro, L.A.; Rubin de Celis, E.; Farach, H.A.; Poole, C.P. jr

    1984-01-01

    Human erythrocytes were labelled with nitroxide, the spin label SYNVAR 101, under various experimantal conditions. A study was made of the influence of antireductants on the labelling efficiency and the kinetics of the radical decay during the labelling process

  14. Sickle erythrocytes inhibit human endothelial cell DNA synthesis

    Weinstein, R.; Zhou, M.A.; Bartlett-Pandite, A.; Wenc, K.

    1990-01-01

    Patients with sickle cell anemia experience severe vascular occlusive phenomena including acute pain crisis and cerebral infarction. Obstruction occurs at both the microvascular and the arterial level, and the clinical presentation of vascular events is heterogeneous, suggesting a complex etiology. Interaction between sickle erythrocytes and the endothelium may contribute to vascular occlusion due to alteration of endothelial function. To investigate this hypothesis, human vascular endothelial cells were overlaid with sickle or normal erythrocytes and stimulated to synthesize DNA. The erythrocytes were sedimented onto replicate monolayers by centrifugation for 10 minutes at 17 g to insure contact with the endothelial cells. Incorporation of 3H-thymidine into endothelial cell DNA was markedly inhibited during contact with sickle erythrocytes. This inhibitory effect was enhanced more than twofold when autologous sickle plasma was present during endothelial cell labeling. Normal erythrocytes, with or without autologous plasma, had a modest effect on endothelial cell DNA synthesis. When sickle erythrocytes in autologous sickle plasma were applied to endothelial monolayers for 1 minute, 10 minutes, or 1 hour and then removed, subsequent DNA synthesis by the endothelial cells was inhibited by 30% to 40%. Although adherence of sickle erythrocytes to the endothelial monolayers was observed under these experimental conditions, the effect of sickle erythrocytes on endothelial DNA synthesis occurred in the absence of significant adherence. Hence, human endothelial cell DNA synthesis is partially inhibited by contact with sickle erythrocytes. The inhibitory effect of sickle erythrocytes occurs during a brief (1 minute) contact with the endothelial monolayers, and persists for at least 6 hours of 3H-thymidine labeling

  15. Human erythrocytes inhibit complement-mediated solubilization of immune complexes by human serum

    Dorval, B.L.

    1987-01-01

    The aim of this study was to develop an autologus human system to evaluate the effects of human erythrocytes on solubilization of immune complex precipitates (IC) by human serum. Incubation of IC with fresh human serum or guinea pig serum resulted in solubilization of IC. When packed erythrocytes were added to human serum or guinea pig serum binding of IC to the erythrocyte occurred and IC solubilization was inhibited significantly (p <.025). Sheep erythrocytes did not bind IC or inhibit IC solubilization. To evaluate the role of human erythrocyte complement receptor (CR1) on these findings, human erythrocytes were treated with trypsin or anti-CR1 antibodies. Both treatments abrogated IC binding to human erythrocytes but did not affect the ability of the human erythrocyte to inhibit IC solubilization. Radioimmunoassay was used to measure C3, C4 and C5 activation in human serum after incubation with IC, human erythrocytes, human erythrocytes plus IC, whole blood or in whole blood plus IC

  16. Radiation sensitivity of human malignant lymphocytes

    Seshadri, R.; Matthews, C.; Morley, A.A.

    1985-01-01

    A simple and rapid in vitro technique to assess the sensitivity of human malignant lymphocytes to roentgen irradiation is described. A variety of established malignant lymphocyte cell lines were cloned in microwells and clone survival was used as the end-point. The survival of the clonogenic malignant lymphocyte down to a fraction of approximately 0.001 could be measured accurately. Except for a T-cell line, the radiation sensitivities of the cell lines were similar to that of normal T-lymphocytes. (orig.)

  17. The complete amino acid sequence of human erythrocyte diphosphoglycerate mutase.

    Haggarty, N W; Dunbar, B; Fothergill, L A

    1983-01-01

    The complete amino acid sequence of human erythrocyte diphosphoglycerate mutase, comprising 239 residues, was determined. The sequence was deduced from the four cyanogen bromide fragments, and from the peptides derived from these fragments after digestion with a number of proteolytic enzymes. Comparison of this sequence with that of the yeast glycolytic enzyme, phosphoglycerate mutase, shows that these enzymes are 47% identical. Most, but not all, of the residues implicated as being important for the activity of the glycolytic mutase are conserved in the erythrocyte diphosphoglycerate mutase. PMID:6313356

  18. Determination of somatic mutations in human erythrocytes by cytometry

    Jensen, R.H.; Langlois, R.G.; Bigbee, W.L.

    1985-01-01

    Flow cytometric assays of human erythrocytes labeled with monoclonal antibodies specific for glycophorin A were used to enumerate variant cells that appear in peripheral blood as a result of somatic gene-loss mutations in erythrocyte precursor cells. The assay was performed on erythrocytes from 10 oncology patients who had received at least one treatment from radiation or mutagenic chemotherapy at least 3 weeks before being assayed. The patients were suffering from many different malignancies (e.g., breast, renal, bone, colon and lung), and were treated with several different mutagenic therapeutics (e.g., cisplatinum, adriamycin, daunomycin, or cyclophosphamide). The frequency of these variant cells is an indication of the amount of mutagenic damage accumulated in the individual's erythropoietic cell population. Comparing these results to HPRT clonogenic assays, we find similar baseline frequencies of somatic mutation as well as similar correlation with mutagenic exposures. 9 refs., 3 figs., 1 tab

  19. Determination of somatic mutations in human erythrocytes by cytometry

    Jensen, R.H.; Langlois, R.G.; Bigbee, W.L.

    1985-06-21

    Flow cytometric assays of human erythrocytes labeled with monoclonal antibodies specific for glycophorin A were used to enumerate variant cells that appear in peripheral blood as a result of somatic gene-loss mutations in erythrocyte precursor cells. The assay was performed on erythrocytes from 10 oncology patients who had received at least one treatment from radiation or mutagenic chemotherapy at least 3 weeks before being assayed. The patients were suffering from many different malignancies (e.g., breast, renal, bone, colon and lung), and were treated with several different mutagenic therapeutics (e.g., cisplatinum, adriamycin, daunomycin, or cyclophosphamide). The frequency of these variant cells is an indication of the amount of mutagenic damage accumulated in the individual's erythropoietic cell population. Comparing these results to HPRT clonogenic assays, we find similar baseline frequencies of somatic mutation as well as similar correlation with mutagenic exposures. 9 refs., 3 figs., 1 tab.

  20. NMR studies of transmembrane electron transport in human erythrocytes

    Kennett, E.C.; Bubb, W.A.; Kuchel, P.W.

    2002-01-01

    Full text: Electron transport systems exist in the plasma membranes of all cells. These systems appear to play a role in cell growth and proliferation, intracellular signalling, hormone responses, apoptotic events, cell defence and perhaps most importantly they enable the cell to respond to changes in the redox state of both the intra- and extracellular environments. Previously, 13 C NMR has been used to study transmembrane electron transport in human erythrocytes, specifically the reduction of extracellular 13 C-ferricyanide. NMR is a particularly useful tool for studying such systems as changes in the metabolic state of the cell can be observed concomitantly with extracellular reductase activity. We investigated the oxidation of extracellular NADH by human erythrocytes using 1 H and 31 P NMR spectroscopy. Recent results for glucose-starved human erythrocytes indicate that, under these conditions, extracellular NADH can be oxidised at the plasma membrane with the electron transfer across the membrane resulting in reduction of intracellular NAD + . The activity is inhibited by known trans-plasma membrane electron transport inhibitors (capsaicin and atebrin) and is unaffected by inhibition of the erythrocyte Band 3 anion transporter. These results suggest that electron import from extracellular NADH allows the cell to re-establish a reducing environment after the normal redox balance is disturbed

  1. Metallic mercury uptake by catalase Part 1 In Vitro metallic mercury uptake by various kind of animals' erythrocytes and purified human erythrocyte catalase

    劒持,堅志

    1980-01-01

    The uptake of metallic mercury was studied using erythrocytes with different catalase activities taken from various kind of animals. The results were: 1) The uptake of metallic mercury by erythrocytes paralleled the activity of catalase in the erythrocytes with and without hydrogen peroxide, suggesting that the erythrocyte catalase activity is related to the uptake of metallic mercury. 2) The uptake of metallic mercury occurred not only with purified human erythrocyte catalase but also with h...

  2. The role of inorganic phosphate in intact human erythrocytes

    Nishiguchi, Eiko; Umeda, Masahiro.

    1988-01-01

    The role of inorganic phosphate in intact human erythrocytes was investigated by phosphorus-31 nuclear magnetic resonance ( 31 P NMR). When erythrocytes stored for 5 weeks were incubated at 37 deg C, pH 7.4, in medium containing 2 mM adenine and 10 mM inosine, with or without 5 mM glucose, a substance of around 4 ppm, as assessed by 31 P NMR chemical shift, was detected in the mixture. However, this substance disappeared by the addition of inorganic phosphate. When erythrocytes stored for 4 weeks in acid citrate dextrose (ACD) solution were incubated with 2 mM adenine, 10 mM inosine, 5 mM glucose, 50 mM inorganic phosphate and 10 mM pyruvate at 37 deg C, pH 7.4, the 2,3-DPG level increased gradually, whereas the ATP level initially increased and then decreased. Intracellular inorganic phosphate appeared to be used for the synthesis of ATP and 2,3-DPG during the first 30 min. of the reaction. These results suggests that the inorganic phosphate accelerates glycolysis by increasing the activity of glycolytic enzymes rather than its direct involvement in synthesizing organic phosphorus compounds in stored erythrocytes. The results also suggests that the reserve energy from ATP synthesis is not sufficient for the synthesis of 2,3-DPG. (author)

  3. Role of aminotransferases in glutamate metabolism of human erythrocytes

    Ellinger, James J. [University of Wisconsin-Madison, Department of Biochemistry (United States); Lewis, Ian A. [Princeton University, Lewis-Sigler Institute for Integrative Genomics (United States); Markley, John L., E-mail: markley@nmrfam.wisc.edu [University of Wisconsin-Madison, Department of Biochemistry (United States)

    2011-04-15

    Human erythrocytes require a continual supply of glutamate to support glutathione synthesis, but are unable to transport this amino acid across their cell membrane. Consequently, erythrocytes rely on de novo glutamate biosynthesis from {alpha}-ketoglutarate and glutamine to maintain intracellular levels of glutamate. Erythrocytic glutamate biosynthesis is catalyzed by three enzymes, alanine aminotransferase (ALT), aspartate aminotransferase (AST), and glutamine aminohydrolase (GA). Although the presence of these enzymes in RBCs has been well documented, the relative contributions of each pathway have not been established. Understanding the relative contributions of each biosynthetic pathway is critical for designing effective therapies for sickle cell disease, hemolytic anemia, pulmonary hypertension, and other glutathione-related disorders. In this study, we use multidimensional {sup 1}H-{sup 13}C nuclear magnetic resonance (NMR) spectroscopy and multiple reaction mode mass spectrometry (MRM-MS) to measure the kinetics of de novo glutamate biosynthesis via AST, ALT, and GA in intact cells and RBC lysates. We show that up to 89% of the erythrocyte glutamate pool can be derived from ALT and that ALT-derived glutamate is subsequently used for glutathione synthesis.

  4. Purification and properties of enolase of human erythrocytes

    Hoorn, R.K.J.; Flikweert, J.P.; Staal, Gerard E.J.

    1974-01-01

    1. 1. Human erythrocyte enolase (2-phospho-D-glycerate hydrolyase, EC 4.2.1.11) was purified I000-fold. 2. 2. The pH-optimum was at pH 6.5. The molecular weight, estimated by gel filtration, was found to be 95,000 ± 5,000. 3. 3. Electrophoresis on agar-agarose at pH 8.5 and 6.4 showed only one

  5. The complete amino acid sequence of human erythrocyte diphosphoglycerate mutase.

    Haggarty, N W; Dunbar, B; Fothergill, L A

    1983-01-01

    The complete amino acid sequence of human erythrocyte diphosphoglycerate mutase, comprising 239 residues, was determined. The sequence was deduced from the four cyanogen bromide fragments, and from the peptides derived from these fragments after digestion with a number of proteolytic enzymes. Comparison of this sequence with that of the yeast glycolytic enzyme, phosphoglycerate mutase, shows that these enzymes are 47% identical. Most, but not all, of the residues implicated as being important...

  6. The erythrocyte membrane in human muscular dystrophy

    W. Ruitenbeek (Willem)

    1979-01-01

    textabstractMore than 250 different forms of human neuromuscular diseases are known. They differ in age of onset, severity of weakness, rate of progression, type of inheritance, groups of muscles affected, frequency of incidence. Sometimes the clinical symptoms are not restricted to nervous

  7. Transport of 3-bromopyruvate across the human erythrocyte membrane.

    Sadowska-Bartosz, Izabela; Soszyński, Mirosław; Ułaszewski, Stanisław; Ko, Young; Bartosz, Grzegorz

    2014-06-01

    3-Bromopyruvic acid (3-BP) is a promising anticancer compound because it is a strong inhibitor of glycolytic enzymes, especially glyceraldehyde 3-phosphate dehydrogenase. The Warburg effect means that malignant cells are much more dependent on glycolysis than normal cells. Potential complications of anticancer therapy with 3-BP are side effects due to its interaction with normal cells, especially erythrocytes. Transport into cells is critical for 3-BP to have intracellular effects. The aim of our study was the kinetic characterization of 3-BP transport into human erythrocytes. 3-BP uptake by erythrocytes was linear within the first 3 min and pH-dependent. The transport rate decreased with increasing pH in the range of 6.0-8.0. The Km and Vm values for 3-BP transport were 0.89 mM and 0.94 mmol/(l cells x min), respectively. The transport was inhibited competitively by pyruvate and significantly inhibited by DIDS, SITS, and 1-cyano-4-hydroxycinnamic acid. Flavonoids also inhibited 3-BP transport: the most potent inhibition was found for luteolin and quercetin.

  8. Proton NMR studies of creatine in human erythrocytes

    Kuchel, P W; Chapman, B E [Sydney Univ. (Australia). Dept. of Biochemistry

    1983-09-01

    Proton spin-echo nuclear magnetic resonance spectroscopy was used to measure the relative levels of some metabolites in intact human erythrocytes that had been fractionated by density gradient centrifugation. Age dependent changes in the concentrations of free glycine, choline and ergothioneine were seen for the first time, while glutathione was essentially invariant. In addition, there was a 10-fold decrease in creatine levels from the youngest to oldest cells. This confirms earlier reports and provides a simple explanation for the variable creatine resonance intensities seen in spectra obtained from different erythrocyte samples prepared from the same donor. The different chemical shifts of the methylene resonances of creatine and creatine phosphate was demonstrated and hence confirmed that the bulk of the creatine in intact erythrocytes is not phosphorylated. The chemical shift difference enabled the monitoring of the creatine phosphokinase catalysed reaction in lysates to which the rabbit muscle enzyme had been added. This experiment indicated that the enzyme is not significantly inhibited by factors in the lysates, and introduced a new means of assaying the in situ activity of the enzyme.

  9. Proton NMR studies of creatine in human erythrocytes

    Kuchel, P.W.; Chapman, B.E.

    1983-01-01

    Proton spin-echo nuclear magnetic resonance spectroscopy was used to measure the relative levels of some metabolites in intact human erythrocytes that had been fractionated by density gradient centrifugation. Age dependent changes in the concentrations of free glycine, choline and ergothioneine were seen for the first time, while glutathione was essentially invariant. In addition, there was a 10-fold decrease in creatine levels from the youngest to oldest cells. This confirms earlier reports and provides a simple explanation for the variable creatine resonance intensities seen in spectra obtained from different erythrocyte samples prepared from the same donor. The different chemical shifts of the methylene resonances of creatine and creatine phosphate was demonstrated and hence confirmed that the bulk of the creatine in intact erythrocytes is not phosphorylated. The chemical shift difference enabled the monitoring of the creatine phosphokinase catalysed reaction in lysates to which the rabbit muscle enzyme had been added. This experiment indicated that the enzyme is not significantly inhibited by factors in the lysates, and introduced a new means of assaying the in situ activity of the enzyme. (author)

  10. Immunophenotypic lymphocyte profiles in human african trypanosomiasis.

    Caroline Boda

    Full Text Available Human African trypanosomiasis (HAT is a deadly vector-born disease caused by an extracellular parasite, the trypanosome. Little is known about the cellular immune responses elicited by this parasite in humans. We used multiparameter flow cytometry to characterize leukocyte immunophenotypes in the blood and cerebrospinal fluid (CSF of 33 HAT patients and 27 healthy controls identified during a screening campaign in Angola and Gabon. We evaluated the subsets and activation markers of B and T lymphocytes. Patients had a higher percentage of CD19+ B lymphocytes and activated B lymphocytes in the blood than did controls, but lacked activated CD4+ T lymphocytes (CD25+. Patients displayed no increase in the percentage of activated CD8+ T cells (HLA-DR+, CD69+ or CD25+, but memory CD8 T-cell levels (CD8+CD45RA2 were significantly lower in patients than in controls, as were effector CD8 T-cell levels (CD8+CD45RA+CD62L2. No relationship was found between these blood immunophenotypes and disease severity (stage 1 vs 2. However, CD19+ B-cell levels in the CSF increased with disease severity. The patterns of T and B cell activation in HAT patients suggest that immunomodulatory mechanisms may operate during infection. Determinations of CD19+ B-cell levels in the CSF could improve disease staging.

  11. Discrimination of human cytotoxic lymphocytes from regulatory and B-lymphocytes by orthogonal light scattering

    Terstappen, Leonardus Wendelinus Mathias Marie; de Grooth, B.G.; ten Napel, C.H.H.; van Berkel, W.; Greve, Jan

    1986-01-01

    Light scattering properties of human lymphocyte subpopulations selected by immunofluorescence were studied with a flow cytometer. Regulatory and B-lymphocytes showed a low orthogonal light scatter signal, whereas cytotoxic lymphocytes identified with leu-7, leu-11 and leu-15 revealed a large

  12. Human erythrocyte electrofusion kinetics monitored by aqueous contents mixing.

    Stenger, D A; Hui, S W

    1988-01-01

    The kinetics of electrically induced fusion of human erythrocyte ghosts were monitored by the Tb/DPA and ANTS/DPX fluorescence fusion assays. Ghosts were aligned by dielectrophoresis using a 3-MHz 350-V/cm alternating field and were fused by single 15- or 50-microseconds electric field pulses of amplitude 2.5-5.0 kV/cm. Fusion was detected immediately after the pulse. The peak fluorescence change due to fusion was always obtained within 7 s of pulse application, and was highest for a 5.0 kV/c...

  13. Analysis in cytokinesis-blocked human lymphocytes

    Catena, C.; Mattoni, A.

    1987-01-01

    Biological dosimetry can be considered as an additional method to physical dosimetry for estimating dose absorption after exposure to ionizing radiation. Fully validated as well as new promising approaches in this field are reviewed. Recent experiments, carried out in our laboratory, on the analysis of micronuclei in cytokinesis-blocked human lymphocytes are presented. The possible relevance of differential human individual response to ionizing radiation, in view of the occurrence of radiosensitive syndromes, for the estimation of the absorbed dose in human is also discussed

  14. Comparison of two different techniques on the human lymphocytes morphology and sensitivity to gamma radiation

    Kol, R.

    1985-02-01

    The lymphocytes in the peripheral blood are divided into two main subclasses: T cells and B cells. These differ from each other in function and in their sensitivity to radiation. The effort to study which group is more sensitive to radiation has resulted in many contradictory results. In the present study we examined whether the methods that are used to separate the lymphocytes from the whole blood, before their separation into subclasses, have an effect on the cells and whether this might contribute to the contradictory results. Blood samples were taken from several normal donors and each sample was devided into two fractions. Lymphocytes in each fraction were separated by one of the two following methods: a) sedimentation of erythrocytes by gravitation; b) separation on Ficoll-Paque density gradient. For cells obtained by these two methods, the ultrastructure was examined by electron microscopy and their ability to incorporate radioactive thymidine was measured. Samples separated on Ficoll-Paque showed a subpopulation with morphological changes similar to those occuring in lymphocytes undergoing stimulation. Unstimulated cells separated on Ficoll-Paque showed greater sensitivity to radiation. The effect of gamma radiation on the capability of lymphocytes to undergo transformation in response to three mitogens; PHA, PWM and Con A was examined. Different mitogens stimulate different lymphocytes subpopulations. There was no difference between the two separation methods regarding the sensitivity to gamma radiation of stimulation by PAH and PWM. The transformation by Con A of lymphocytes separated on Ficoll-Paque was more radiosensitive. This could indicate that the separation by Ficoll-Paque density gradient causes a selective depletion of T lymphocytes that react with Con A and are considered more radioresistant. The use of different methods for separating lymphocytes from whole blood- each has a different influence on the cells- can contribute to contradictory

  15. Evaluation of Hemagglutination Activity of Chitosan Nanoparticles Using Human Erythrocytes

    Jefferson Muniz de Lima

    2015-01-01

    Full Text Available Chitosan is a polysaccharide composed of randomly distributed chains of β-(1-4 D-glucosamine and N-acetyl-D-glucosamine. This compound is obtained by partial or total deacetylation of chitin in acidic solution. The chitosan-based hemostatic agents have been gaining much attention in the management of bleeding. The aim of this study was to evaluate in vitro hemagglutination activity of chitosan nanoparticles using human erythrocytes. The preparation of nanoparticles was achieved by ionotropic gelification technique followed by neutralization with NaOH 1 mol/L−1. The hemagglutination activity was performed on a solution of 2% erythrocytes (pH 7.4 on PBS collected from five healthy volunteers. The hemolysis determination was made by spectrophotometric analysis. Chitosan nanoparticle solutions without NaOH addition changed the reddish colour of the wells into brown, suggesting an oxidative reaction of hemoglobin and possible cell lysis. All neutralized solutions of chitosan nanoparticles presented positive haemagglutination, without any change in reaction color. Chitosan nanoparticles presented hemolytic activity ranging from 186.20 to 223.12%, while neutralized solutions ranged from 2.56 to 72.54%, comparing to distilled water. Results highlight the need for development of new routes of synthesis of chitosan nanoparticles within human physiologic pH.

  16. Acute dark chocolate ingestion is beneficial for hemodynamics via enhancement of erythrocyte deformability in healthy humans.

    Radosinska, Jana; Horvathova, Martina; Frimmel, Karel; Muchova, Jana; Vidosovicova, Maria; Vazan, Rastislav; Bernatova, Iveta

    2017-03-01

    Erythrocyte deformability is an important property of erythrocytes that considerably affects blood flow and hemodynamics. The high content of polyphenols present in dark chocolate has been reported to play a protective role in functionality of erythrocytes. We hypothesized that chocolate might influence erythrocytes not only after repeated chronic intake, but also immediately after its ingestion. Thus, we determined the acute effect of dark chocolate and milk (with lower content of biologically active substances) chocolate intake on erythrocyte deformability. We also focused on selected factors that may affect erythrocyte deformability, specifically nitric oxide production in erythrocytes and total antioxidant capacity of plasma. We determined posttreatment changes in the mentioned parameters 2hours after consumption of chocolate compared with their levels before consumption of chocolate. In contrast to milk chocolate intake, the dark chocolate led to a significantly higher increase in erythrocyte deformability. Nitric oxide production in erythrocytes was not changed after dark chocolate intake, but significantly decreased after milk chocolate. The plasma total antioxidant capacity remained unaffected after ingestion of both chocolates. We conclude that our hypothesis was confirmed. Single ingestion of dark chocolate improved erythrocyte deformability despite unchanged nitric oxide production and antioxidant capacity of plasma. Increased deformability of erythrocytes may considerably improve rheological properties of blood and thus hemodynamics in humans, resulting in better tissue oxygenation. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. Blood-group-Ii-active gangliosides of human erythrocyte membranes

    Feizi, T.; Childs, R.A.; Hakomori, S.-I.; Powell, M.E.

    1978-01-01

    More than ten new types of gangliosides, in addition to haematoside and sialosylparagloboside, were isolated from human erythrocyte membranes. These were separated by successive chromatographies on DAEA-Sephadex, on porous silica-gel columns and on thin-layer silica gel as acetylated compounds. Highly potent blood-group-Ii and moderate blood-group-H activities were demonstrated in some of the ganglioside fractions. The gangliosides incorporated into chlolesterol/phosphatidylcholine liposomes stoicheiometrically inhibited binding of anti-(blood-group-I and i) antibodies to a radioiodinated blood-group-Ii-active glycoprotein. The fraction with the highest blood-group-I activity, I(g) fraction, behaved like sialosyl-deca- to dodeca-glycosylceramides on t.l.c. Certain blood-group-I and most of the i-determinants were in partially or completely cryptic form and could be unmasked by sialidase treatment. Thus the I and i antigens, which are known to occur on internal structures of blood-group-ABH-active glycoproteins in secretions, also occur in the interior of the carbohydrate chains of erythrocyte gangliosides. (author)

  18. Radiosensitivity of human lymphocytes and thymocytes

    Kwan, D.K.; Norman, A.

    1977-01-01

    The in vitro survival of human peripheral blood lymphocytes and thymocytes was measured 4 days following graded doses of γ radiation. Results indicate considerable heterogeneity among lymphocyte subpopulations with respect to radiosensitivity. Total T lymphocytes were characterized by rosette formation with neuraminidase-treated sheep red blood cells (nSRBC); early T (T/sub E/) cells, by early rosettes; and B cells, by their inability to form nSRBC rosettes. Late T (T/sub L/) cells were defined as T -- T/sub E/. Survival curves of T, T/sub E/, and B cells are biphasic. The radiosensitive and radioresistant components of T, T/sub E/, and B cells all have a D 0 of about 50 and 550 rad, respectively. B cells appeared to be slightly more radiosensitive than T cells. T/sub L/ cells and thymocytes, however, appeared to be homogeneous with respect to radiosensitivity, both having D 0 values of about 135 rad. The survival of T cells in mixed T and B cell cultures resembled that of separated T cells, suggesting that ionizing radiation has no significant effect on rosette formation. It also indicates that interactions of T and B cells do not significantly affect their radiation responses

  19. Electron Pathways through Erythrocyte Plasma Membrane in Human Physiology and Pathology: Potential Redox Biomarker?

    Matteucci, Elena; Giampietro, Ottavio

    2007-01-01

    Erythrocytes are involved in the transport of oxygen and carbon dioxide in the body. Since pH is the influential factor in the Bohr-Haldane effect, pHi is actively maintained via secondary active transports Na+/H+ exchange and HC3 -/Cl- anion exchanger. Because of the redox properties of the iron, hemoglobin generates reactive oxygen species and thus, the human erythrocyte is constantly exposed to oxidative damage. Although the adult erythrocyte lacks protein synthesis and cannot restore dama...

  20. DNA repair in PHA stimulated human lymphocytes

    Catena, C.; Mattoni, A.

    1984-01-01

    Damage an repair of radiation induced DNA strand breaks were measured by alkaline lysis and hydroxyapatite chromatography. PHA stimulated human lymphocytes show that the rejoining process is complete within the first 50 min., afterwords secondary DNA damage and chromatid aberration. DNA repair, in synchronized culture, allows to evaluate individual repair capacity and this in turn can contribute to the discovery of individual who, although they do not demonstrate apparent clinical signs, are carriers of DNA repair deficiency. Being evident that a correlation exists between DNA repair capacity and carcinogenesis, the possibility of evaluating the existent relationship between DNA repair and survival in tumor cells comes therefore into discussion

  1. T-dependence of human B lymphocyte proliferative response to mitogens.

    Brochier, J; Samarut, C; Gueho, J P; Revillard, J P

    1976-01-01

    Human peripheral blood and tonsil lymphocytes were fractionated on anti-Ig-coated Sephadex columns or by centrifugation after rosetting with native sheep erythrocytes. Both methods allowed the recovery of B and T-enriched populations the purity of which was checked by fluorescein-labelled anti-Ig serum, E and EAC rosette formation, and heterologous antisera specific for B or T lymphocytes. The proliferative response of T cells to PHA, Con A, PWM, and ALS was not found different from that of unfractionated cells, whereas no response of the B cells could be observed to these mitogens providing that no contaminating T cells were present. Addition of T lymphocytes to these unresponsive B cells allowed them to respond to phytomitogens, but not to ALS. X-irradiated T cells could, to some extent, replace the diving T lymphocytes; no T-replacing factor could be found in cell-free supernatants from T cells, whether or not they had been activated by mitrogens. This model of B-T cooperation appears useful for studying the differentiation and maturation of human B lymphocytes.

  2. Solubilization of human erythrocyte membranes by ASB detergents

    C.C. Domingues

    2008-09-01

    Full Text Available Understanding the membrane solubilization process and finding effective solubilizing agents are crucial challenges in biochemical research. Here we report results on the interaction of the novel linear alkylamido propyl dimethyl amino propanosulfonate detergents, ASB-14 and ASB-16, with human erythrocyte membranes. An estimation of the critical micelle concentration of these zwitterionic detergents (ASB-14 = 100 µM and ASB-16 = 10 µM was obtained using electron paramagnetic resonance. The amount of proteins and cholesterol solubilized from erythrocytes by these detergents was then determined. The hemolytic activities of the ASB detergents were assayed and the detergent/lipid molar ratios for the onset of hemolysis (Re sat and total lysis (Re sol were calculated, allowing the determination of the membrane binding constants (Kb. ASB-14 presented lower membrane affinity (Kb = 7050 M-1 than ASB-16 (Kb = 15610 M-1. The amount of proteins and cholesterol solubilized by both ASB detergents was higher while Re sat values (0.22 and 0.08 detergent/lipid for ASB-14 and ASB-16, respectively were smaller than those observed with the classic detergents CHAPS and Triton X-100. These results reveal that, besides their well-known use as membrane protein solubilizers to enhance the resolution of two dimensional electrophoresis/mass spectrometry, ASB-14 and ASB-16 are strong hemolytic agents. We propose that the physicochemical properties of ASB detergents determine their membrane disruption efficiency and can help to explain the improvement in the solubilization of membrane proteins, as reported in the literature.

  3. Comparative studies on osmosis based encapsulation of sodium diclofenac in porcine and outdated human erythrocyte ghosts.

    Bukara, Katarina; Drvenica, Ivana; Ilić, Vesna; Stančić, Ana; Mišić, Danijela; Vasić, Borislav; Gajić, Radoš; Vučetić, Dušan; Kiekens, Filip; Bugarski, Branko

    2016-12-20

    The objective of our study was to develop controlled drug delivery system based on erythrocyte ghosts for amphiphilic compound sodium diclofenac considering the differences between erythrocytes derived from two readily available materials - porcine slaughterhouse and outdated transfusion human blood. Starting erythrocytes, empty erythrocyte ghosts and diclofenac loaded ghosts were compared in terms of the encapsulation efficiency, drug releasing profiles, size distribution, surface charge, conductivity, surface roughness and morphology. The encapsulation of sodium diclofenac was performed by an osmosis based process - gradual hemolysis. During this process sodium diclofenac exerted mild and delayed antihemolytic effect and increased potassium efflux in porcine but not in outdated human erythrocytes. FTIR spectra revealed lack of any membrane lipid disorder and chemical reaction with sodium diclofenac in encapsulated ghosts. Outdated human erythrocyte ghosts with detected nanoscale damages and reduced ability to shrink had encapsulation efficiency of only 8%. On the other hand, porcine erythrocyte ghosts had encapsulation efficiency of 37% and relatively slow drug release rate. More preserved structure and functional properties of porcine erythrocytes related to their superior encapsulation and release performances, define them as more appropriate for the usage in sodium diclofenac encapsulation process. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. Morphological Effects and Antioxidant Capacity of Solanum crispum (Natre) In Vitro Assayed on Human Erythrocytes.

    Suwalsky, Mario; Ramírez, Patricia; Avello, Marcia; Villena, Fernando; Gallardo, María José; Barriga, Andrés; Manrique-Moreno, Marcela

    2016-06-01

    In order to gain insight into the molecular mechanism of the antioxidant properties of Solanum crispum, aqueous extracts of its leaves were assayed on human erythrocytes and molecular models of its membrane. Phenolics and alkaloids were detected by HPLC-MS. Scanning electron and defocusing microscopy showed that S. crispum changed erythrocytes from the normal shape to echinocytes. These results imply that molecules present in the aqueous extracts were located in the outer monolayer of the erythrocyte membrane. Dimyristoylphosphatidylcholine (DMPC) and dimyristoylphosphatidylethanolamine (DMPE) were chosen as representative of phospholipid classes located in the outer and inner monolayers of the erythrocyte membrane, respectively. X-ray diffraction showed that S. crispum preferentially interacted with DMPC bilayers. Experiments regarding its antioxidant properties showed that S. crispum neutralized the oxidative capacity of HClO on DMPE bilayers; defocusing microscopy and hemolysis assays demonstrated the protective effect of S. crispum against the oxidant effects of HClO on human erythrocytes.

  5. Telomerase levels control the lifespan of human T lymphocytes

    Roth, Alexander; Yssel, Hans; Pene, Jerome; Chavez, Elizabeth A.; Schertzer, Mike; Lansdorp, Peter M.; Spits, Hergen; Luiten, Rosalie M.

    2003-01-01

    The loss of telomeric DNA with each cell division contributes to the limited replicative lifespan of human T lymphocytes. Although telomerase is transiently expressed in T lymphocytes upon activation, it is insufficient to confer immortality. We have previously shown that immortalization of human

  6. Progranulin Inhibits Human T Lymphocyte Proliferation by Inducing the Formation of Regulatory T Lymphocytes

    Kyu Hwan Kwack

    2017-01-01

    Full Text Available We have examined the effect of progranulin (PGRN on human T cell proliferation and its underlying mechanism. We show that PGRN inhibits the PHA-induced multiplication of T lymphocytes. It increases the number of iTregs when T lymphocytes are activated by PHA but does not do so in the absence of PHA. PGRN-mediated inhibition of T lymphocyte proliferation, as well as the induction of iTregs, was completely reversed by a TGF-β inhibitor or a Treg inhibitor. PGRN induced TGF-β secretion in the presence of PHA whereas it did not in the absence of PHA. Our findings indicate that PGRN suppresses T lymphocyte proliferation by enhancing the formation of iTregs from activated T lymphocytes in response to TGF-β.

  7. Isolation of low-molecular-weight lead-binding protein from human erythrocytes

    Raghavan, S.R.V.; Gonick, H.C.

    1977-01-01

    In blood, lead is mainly associated with erythrocytes and only a very small amount is found in plasma. Previously it was thought that the lead was bound to the erythrocyte cell membrane but more recently it has been observed that lead is bound primarily to the cell contents, ostensibly hemoglobin. In examining the lead-binding properties of normal human erythrocytes and those of lead-exposed industrial workers, we have found that, whereas lead binds only to hemoglobin in normal erythrocytes, there is also appreciable binding of lead to a low-molecular weight-protein in erythrocytes from lead-exposed workers. The synthesis of this protein may be induced by lead exposure. The 10,000 molecular weight protein may act as a storage site and mechanism for segregating lead in a non-toxic form

  8. Diffusion properties of band 3 in human erythrocytes

    Spector, Jeffrey O.

    The plasma membrane of the human erythrocyte (RBC) is a six fold symmetric network held together at various pinning points by several multi-protein complexes. This unique architecture is what gives the RBC its remarkable material properties and any disruptions to the network can have severe consequences for the cell. Band 3 is a major transmembrane protein that plays the role of linking the fluid lipid bilayer to the cytoskeletal network. To interrogate the structural integrity of the RBC membrane we have tracked individual band 3 molecules in RBCs displaying a variety of pathologies that are all a consequence of membrane or network related defects. These diseases are spherocytosis, elliptocytosis, and pyropokilocytosis. We have also investigated the protein related diseases sickle cell, and south east asian ovalocytosis. To assess the impact that the network has on the dynamic organization of the cell we have also studied the mobility of band 3 in RBC progenitor cells. Individual band 3 molecules were imaged at 120 frames/second and their diffusion coefficients and compartment sizes recorded. The distributions of the compartment sizes combined with the information about the short and long time diffusion of band 3 has given us insight into the architecture of the membrane in normal and diseased cells. The observation that different membrane pathologies can be distinguished, even to the point of different molecular origins of the same disease, implies that the mobility of transmembrane proteins may be a useful tool for characterizing the "health" of the membrane.

  9. Predictive radiosensitivity tests in human lymphocytes

    Di Giorgio, Marina; Vallerga, Maria B.; Taja, Maria R.; Sardi, M.; Busto, E.; Mairal, L.; Roth, B.; Menendez, P.; Bonomi, M.

    2004-01-01

    Individual radiosensitivity is an inherent characteristic, associated with an abnormally increased reaction to ionising radiation of both the whole body and cells derived from body tissues. Human population is not uniform in its radiation sensitivity. Radiosensitive sub-groups exist, which would suffer an increased incidence of both deterministic and stochastic effects. Clinical studies have suggested that a large part of the spectrum of normal tissue reaction may be due to differences in individual radiosensitivity. The identification of such sub-groups should be relevant for radiation therapy and radiation protection purposes. It is suggested that DNA repair mechanisms are involved. Consequently, the characterization of DNA repair in lymphocytes through cytokinesis blocked micronucleus (MN) and alkaline single-cell microgel electrophoresis (comet) assays could be a suitable approache to evaluate individual radiosensitivity in vitro. The aims of this study were: 1) To assess the in vitro radiosensitivity of peripheral blood lymphocytes from two groups of cancer patients (prospectively and retrospectively studied), using MN and comet assays, in comparison with the clinical radiation reaction and 2) To test the predictive potential of both techniques for the identification of radiosensitivity sub-groups. 38 cancer patients receiving radiation therapy were enrolled in this study. 19 patients were evaluated prior, mid-way and on completion of treatment (prospective group) and 19 patients were evaluated about 6-18 month after radiotherapy (retrospective group). Cytogenetic data from the prospective group were analysed using a mathematical model to evaluate the attenuation of the cytogenetic effect as a function of the time between a single exposure and blood sampling, estimating a cytogenetic recovery factor k. In the retrospective group, blood samples were irradiated in vitro with 0 (control) or 2 Gy and evaluated using MN test. Cytogenetic data were analysed

  10. Effects of phenylpropanolamine (PPA) on in vitro human erythrocyte membranes and molecular models

    Suwalsky, Mario, E-mail: msuwalsk@udec.cl [Faculty of Chemical Sciences, University of Concepcion, Concepcion (Chile); Zambrano, Pablo; Mennickent, Sigrid [Faculty of Pharmacy, University of Concepcion, Concepcion (Chile); Villena, Fernando [Faculty of Biological Sciences, University of Concepcion, Concepcion (Chile); Sotomayor, Carlos P.; Aguilar, Luis F. [Instituto de Quimica, Pontificia Universidad Catolica de Valparaiso, Valparaiso (Chile); Bolognin, Silvia [CNR-Institute for Biomedical Technologies, University of Padova, Padova (Italy)

    2011-03-18

    Research highlights: {yields} PPA is a common ingredient in cough-cold medication and appetite suppressants. {yields} Reports on its effects on human erythrocytes are very scarce. {yields} We found that PPA induced in vitro morphological changes to human erythrocytes. {yields} PPA interacted with isolated unsealed human erythrocyte membranes. {yields} PPA interacted with class of lipid present in the erythrocyte membrane outer monolayer. -- Abstract: Norephedrine, also called phenylpropanolamine (PPA), is a synthetic form of the ephedrine alkaloid. After reports of the occurrence of intracranial hemorrhage and other adverse effects, including several deaths, PPA is no longer sold in USA and Canada. Despite the extensive information about PPA toxicity, reports on its effects on cell membranes are scarce. With the aim to better understand the molecular mechanisms of the interaction of PPA with cell membranes, ranges of concentrations were incubated with intact human erythrocytes, isolated unsealed human erythrocyte membranes (IUM), and molecular models of cell membranes. The latter consisted in bilayers built-up of dimyristoylphosphatidylcholine (DMPC) and dimyristoylphosphatidylethanolamine (DMPE), phospholipid classes present in the outer and inner monolayers of most plasmatic cell membranes, respectively. The capacity of PPA to perturb the bilayer structures of DMPC and DMPE was assessed by X-ray diffraction, DMPC large unilamellar vesicles (LUV) and IUM were studied by fluorescence spectroscopy, and intact human erythrocytes were observed by scanning electron microscopy (SEM). This study presents evidence that PPA affects human red cell membranes as follows: (a) in SEM studies on human erythrocytes it was observed that 0.5 mM PPA induced shape changes; (b) in IUM PPA induced a sharp decrease in the fluorescence anisotropy in the lipid bilayer acyl chains in a concentration range lower than 100 {mu}M; (c) X-ray diffraction studies showed that PPA in the 0.1-0.5 m

  11. Inhibition by nucleosides of glucose-transport activity in human erythrocytes.

    Jarvis, S M

    1988-01-01

    The interaction of nucleosides with the glucose carrier of human erythrocytes was examined by studying the effect of nucleosides on reversible cytochalasin B-binding activity and glucose transport. Adenosine, inosine and thymidine were more potent inhibitors of cytochalasin B binding to human erythrocyte membranes than was D-glucose [IC50 (concentration causing 50% inhibition) values of 10, 24, 28 and 38 mM respectively]. Moreover, low concentrations of thymidine and adenosine inhibited D-glu...

  12. Effect of chloroquine on human lymphocyte proliferation

    Bygbjerg, Ib Christian; Flachs, H

    1986-01-01

    The effect of chloroquine on human blood mononuclear cells was studied. High concentrations of chloroquine in vitro profoundly suppressed the proliferation of mitogen- and antigen-stimulated cells, as indicated by decreased 14C-thymidine incorporation. Lower concentrations of chloroquine increase...... to large particulate antigens; the response to small antigens was not affected. The mode of action of chloroquine and the possible consequences of the findings for dosage of chloroquine when used for malaria prophylaxis is discussed.......The effect of chloroquine on human blood mononuclear cells was studied. High concentrations of chloroquine in vitro profoundly suppressed the proliferation of mitogen- and antigen-stimulated cells, as indicated by decreased 14C-thymidine incorporation. Lower concentrations of chloroquine increased...... the response to pokeweed mitogen. The response to concanavalin A and to various antigens was suppressed, especially the response to large particulate antigens. Oral intake of 300 mg of chloroquine base/week did not affect the lymphocyte proliferative responses. 600 mg of base/week decreased the response...

  13. Activation of human T lymphocytes by Leishmania lipophosphoglycan

    Kemp, M; Theander, T G; Handman, E

    1991-01-01

    This study describes Leishmania antigen-induced activation of lymphocytes isolated from Kenyan donors, previously treated for visceral leishmaniasis, and from Danish and Kenyan controls. Peripheral blood mononuclear cells (PBMC) from cured Kala-Azar patients proliferated and produced Interferon......, the results suggest that human T lymphocytes can respond to glycolipid antigens....

  14. Carotenoid levels in human lymphocytes, measured by Raman microspectroscopy

    Ramanauskaite, R B; SegersNolten, IGMJ; DeGrauw, K J; Sijtsema, N M; VanderMaas, L; Greve, J; Otto, C; Figdor, C G

    1997-01-01

    Carotenoid levels in lymphocytes obtained from peripheral blood of healthy people have been investigated by Raman microspectroscopy. We observed that carotenoids are concentrated in so-called ''Gall bodies''. The level of carotenoids in living human lymphocytes was found to be age-dependent and to

  15. The osmotic fragility of human erythrocytes is inhibited by laser irradiation

    Habodaszova, D.; Sikurova, L.; Waczulikova, I.

    2004-01-01

    In this study we investigated the influence of green laser irradiation (532 nm, 30 mW, 31,7 J/cm 2 ) on the membrane integrity of human erythrocytes and compared the results with the effect of infrared laser irradiation (810 nm, 50 mW, 31,3 J/cm 2 ). To evaluate the membrane integrity of erythrocytes, one clinical parameter, the osmotic fragility, was investigated. We observed a decrease in osmotic fragility of the erythrocytes after irradiation by the green laser light as well as by the infrared laser compared to non-irradiated controls (Authors)

  16. Spontaneous unscheduled DNA synthesis in human lymphocytes

    Forell, B.; Myers, L.S. Jr.; Norman, A.

    1979-01-01

    The rate of spontaneous unscheduled DNA synthesis in human lymphocytes was estimated from measurements of tritiated thymidine incorporation into double-stranded DNA (ds-DNA) during incubation of cells in vitro. The contribution of scheduled DNA synthesis to the observed incorporation was reduced by inhibiting replication with hydroxyurea and by separating freshly replicated single-stranded DNA (ss-DNA) from repaired ds-DNA by column chromatography. The residual contribution of scheduled DNA synthesis was estimated by observing effects on thymidine incorporation of: (a) increasing the rate of production of apurinic sites, and alternatively, (b) increasing the number of cells in S-phase. Corrections based on estimates of endogenous pool size were also made. The rate of spontaneous unscheduled DNA synthesis is estimated to be 490 +- 120 thymidine molecules incorporated per cell per hour. These results compare favorably with estimates made from rates of depurination and depyrimidination of DNA, measured in molecular systems if we assume thymidine is incorporated by a short patch mechanism which incorporates an average of four bases per lesion

  17. PIXE elemental analysis of erythrocyte and blood plasma samples from human pregnancies

    Borbely-Kiss, I.; Koltay, E.; Laszlo, S.; Szabo, Gy.

    1984-01-01

    Elemental concentrations of P, S, Cl, K, Ca, Fe, Ni, Cu, Zn, Br, Rb have been determined in erythrocyte and blood plasma samples from normal and diabetic human pregnancies. Average values, the dependence of the concentrations on the time during gestation period, the correlation coefficients for pairs of elements as well as for the same elements in plasma and erythrocyte samples are given. A marked difference appeared in a number of cases between normal and diabetic pregnancies. (author)

  18. PIXE elemental analysis of erythrocyte and blood plasma samples from human pregnancies

    Borbely-Kiss, I; Koltay, E; Laszlo, S; Szabo, Gy [Magyar Tudomanyos Akademia, Debrecen. Atommag Kutato Intezete; Goedeny, S [Orvostudomanyi Egyetem, Szeged (Hungary). Szueleszeti es Noegyogyaszati Klinika; Seif El-Nasr, S [Teachers' Coll. for Women, Samia (Kuwait)

    1984-07-01

    Elemental concentrations of P, S, Cl, K, Ca, Fe, Ni, Cu, Zn, Br, Rb have been determined in erythrocyte and blood plasma samples from normal and diabetic human pregnancies. Average values, the dependence of the concentrations on the time during gestation period, the correlation coefficients for pairs of elements as well as for the same elements in plasma and erythrocyte samples are given. A marked difference appeared in a number of cases between normal and diabetic pregnancies. 11 refs.

  19. Fragmentation of Human Erythrocyte Actin following Exposure to Hypoxia

    Risso, A.; Santamaria, B.; Pistarino, E.; Cosulich, M. E.; Pompach, Petr; Bezouška, Karel; Antonutto, G.

    2010-01-01

    Roč. 123, č. 1 (2010), s. 6-13 ISSN 0001-5792 Institutional research plan: CEZ:AV0Z50200510 Keywords : beta-Actin * Erythrocytes * Hypoxia Subject RIV: EE - Microbiology, Virology Impact factor: 1.316, year: 2010

  20. Phosphorylation of intact erythrocytes in human muscular dystrophy

    Johnson, R.M.; Nigro, M.

    1986-01-01

    The uptake of exogenous 32 Pi into the membrane proteins of intact erythrocytes was measured in 8 patients with Duchenne muscular dystrophy. No abnormalities were noted after autoradiographic analysis. This contrasts with earlier results obtained when isolated membranes were phosphorylated with gamma-[ 32 P]ATP, and suggests a possible reinterpretation of those experiments

  1. Erratum Detergent-resistant membranes in human erythrocytes and ...

    Unknown

    Figure 3. Immunodetection of flotillin-2 and band 3 in DRMs isolated from erythrocyte ghosts by various treatments. Flotillin-2. (left) and band 3 (right) Western blotting in ten fractions of 0⋅5 ml each, obtained from the sucrose gradients described in figure 2 and numbered from top to bottom. Flotillin-2 is enriched in DRMs ...

  2. Mercury chloride-induced oxidative stress in human erythrocytes ...

    ONOS

    2010-01-25

    Jan 25, 2010 ... Mercury can exist in the environment as metal, as monovalent and divalent salts and as organomercurials, one of the most important of which is mercuric chloride (HgCl2). It has been shown to induce oxidative stress in erythrocytes through the generation of free radicals and alteration of the.

  3. Human erythrocytes and neuroblastoma cells are affected in vitro by Au(III) ions

    Suwalsky, Mario; Gonzalez, Raquel; Villena, Fernando; Aguilar, Luis F.; Sotomayor, Carlos P.; Bolognin, Silvia; Zatta, Paolo

    2010-01-01

    Gold compounds are well known for their neurological and nephrotoxic implications. However, haematological toxicity is one of the most serious toxic and less studied effects. The lack of information on these aspects of Au(III) prompted us to study the structural effects induced on cell membranes, particularly that of human erythrocytes. AuCl 3 was incubated with intact erythrocytes, isolated unsealed human erythrocyte membranes (IUM) and molecular models of the erythrocyte membrane. The latter consisted of multibilayers of dimyristoylphosphatidylcholine and dimyristoylphosphatidylethanolamine, phospholipids classes located in the outer and inner monolayers of the human erythrocyte membrane, respectively. This report presents evidence that Au(III) interacts with red cell membranes as follows: (a) in scanning electron microscopy studies on human erythrocytes it was observed that Au(III) induced shape changes at a concentration as low as 0.01 μM; (b) in isolated unsealed human erythrocyte membranes Au(III) induced a decrease in the molecular dynamics and/or water content at the glycerol backbone level of the lipid bilayer polar groups in a 5-50 μM concentration range, and (c) X-ray diffraction studies showed that Au(III) in the 10 μm-1 mM range induced increasing structural perturbation only to dimyristoylphosphatidylcholine bilayers. Additional experiments were performed in human neuroblastoma cells SH-SY5Y. A statistically significant decrease of cell viability was observed with Au(III) ranging from 0.1 μM to 100 μM.

  4. Analysis of cytotoxic effects of nickel on human blood lymphocytes.

    Zarei, Mohammad Hadi; Hosseini Shirazi, Seyed Farshad; Aghvami, Marjan; Salimi, Ahmad; Pourahmad, Jalal

    2018-02-01

    Nickel compounds possess many applications in different industrial processes. Human beings are exposed to nickel commonly through occupational exposure and food. Although a few studies so far have investigated the effects of nickel compounds on human lymphocytes, the complete mechanism of cytotoxicity of this metal on human lymphocytes is yet to be determined. The intention of this paper was to determine the cytotoxicity mechanism of water soluble NiCl 2 toward human lymphocytes using the accelerated cytotoxicity mechanisms screening (ACMS) technique. Human lymphocytes were isolated from the blood of healthy subjects based on Ficoll-Paque PLUS standard method. For the assessment of cell viability, lymphocytes were incubated with 0.05-1 mM NiCl 2 for 12 h. Determination of mechanistic parameters was performed 2, 4 and 6 h after treatment of cells with ½ EC50 12h , EC50 12h and 2EC50 12h of NiCl 2 . Our results demonstrate that cytotoxicity of NiCl 2 on human lymphocytes is associated with increased ROS formation, mitochondrial membrane potential collapse, glutathione depletion, lysosomal membrane damage, cellular proteolysis and activation of caspase-3 before cytotoxicity ensued.

  5. Recruitment of human aquaporin 3 to internal membranes in the Plasmodium falciparum infected erythrocyte.

    Bietz, Sven; Montilla, Irine; Külzer, Simone; Przyborski, Jude M; Lingelbach, Klaus

    2009-09-01

    The molecular mechanisms underlying the formation of the parasitophorous vacuolar membrane in Plasmodium falciparum infected erythrocytes are incompletely understood, and the protein composition of this membrane is still enigmatic. Although the differentiated mammalian erythrocyte lacks the machinery required for endocytosis, some reports have described a localisation of host cell membrane proteins at the parasitophorous vacuolar membrane. Aquaporin 3 is an abundant plasma membrane protein of various cells, including mammalian erythrocytes where it is found in distinct oligomeric states. Here we show that human aquaporin 3 is internalized into infected erythrocytes, presumably during or soon after invasion. It is integrated into the PVM where it is organized in novel oligomeric states which are not found in non-infected cells.

  6. Magnetic measurements on human erythrocytes: Normal, beta thalassemia major, and sickle

    Sakhnini, Lama

    2003-05-01

    In this article magnetic measurements were made on human erythrocytes at different hemoglobin states (normal and reduced hemoglobin). Different blood samples: normal, beta thalassemia major, and sickle were studied. Beta thalassemia major and sickle samples were taken from patients receiving lifelong blood transfusion treatment. All samples examined exhibited diamagnetic behavior. Beta thalassemia major and sickle samples showed higher diamagnetic susceptibilities than that for the normal, which was attributed to the increase of membrane to hemoglobin volume ratio of the abnormal cells. Magnetic measurements showed that the erythrocytes in the reduced state showed less diamagnetic response in comparison with erythrocytes in the normal state. Analysis of the paramagnetic component of magnetization curves gave an effective magnetic moment of μeff=7.6 μB per reduced hemoglobin molecule. The same procedure was applied to sickle and beta thalassemia major samples and values for μeff were found to be comparable to that of the normal erythrocytes.

  7. Grape (Vitis vinifera) extracts protects against radiation-induced oxidative stress in human erythrocyte (RBC)

    Ghosh, Subhashis

    2016-01-01

    Ionizing radiation (IR) causes oxidative stress through the overwhelming generation of reactive oxygen species (ROS) in the living cells leading further to the oxidative damage to biomolecules. Grapes (Vitis vinifera) contain several bioactive phytochemicals and are the richest source of antioxidant. In this study, we investigated the radioprotective actions of the grape extracts of two different cultivars, including the Thompson seedless (green) and Kishmish chorni (black) in human erythrocytes. Pretreatment with grape extracts attenuates oxidative stress induced by 4 Gy-radiation in human erythrocytes in vitro. These results suggest that grape extract serve as a potential source of natural antioxidants against the IR-induced oxidative stress and also inhibit apoptosis. Furthermore, the protective action of grape depends on the source of extract (seed, skin or pulp) and type of the cultivars. Effects of grape extracts of different cultivars on protein content, Thiobarbituric acid reactive substances (TBARS) level, reduced glutathione (GSH) content and activities of Catalase, Nitrite, GST, GR in human erythrocytes against -radiation exposure at a dose of 4 Gy are investigated. The grape extracts did not appear to alter the viability of human erythrocytes. Exposure of erythrocytes to the -irradiation at a dose of 4 Gy significantly increased the extent of formation of TBARS, while decreased the level of GSH and activities of CAT, GSSG , GST, GR in the erythrocytes as compared to the non-irradiated control counterparts. This was significantly attenuated by the pretreatment with the grape seed extracts (p<0.001) and significantly with the skin extracts (p<0.05) compared to the ionizing radiation exposed group. Moreover, protection offered by the seed extracts was found significantly better than that was offered by the pulp extract of the same cultivar. In conclusion, our results suggested that the grape extracts significantly attenuated IR induced oxidative stress and

  8. Influence of Cocoa Flavanols and Procyanidins on Free Radical-induced Human Erythrocyte Hemolysis

    Qin Yan Zhu

    2005-01-01

    Full Text Available Cocoa can be a rich source of antioxidants including the flavan-3-ols, epicatechin and catechin, and their oligomers (procyanidins. While these flavonoids have been reported to reduce the rate of free radical-induced erythrocyte hemolysis in experimental animal models, little is known about their effect on human erythrocyte hemolysis. The major objective of this work was to study the effect of a flavonoid-rich cocoa beverage on the resistance of human erythrocytes to oxidative stress. A second objective was to assess the effects of select purified cocoa flavonoids, epicatechin, catechin, the procyanidin Dimer B2 and one of its major metabolites, 3ʹ-O-methyl epicatechin, on free radical-induced erythrocyte hemolysis in vitro. Peripheral blood was obtained from 8 healthy subjects before and 1, 2, 4 and 8 h after consuming a flavonoid-rich cocoa beverage that provided 0.25 g/kg body weight (BW, 0.375 or 0.50 g/kg BW of cocoa. Plasma flavanol and dimer concentrations were determined for each subject. Erythrocyte hemolysis was evaluated using a controlled peroxidation reaction. Epicatechin, catechin, 3ʹ-O-methyl epicatechin and (--epicatechin-(4β > 8epicatechin (Dimer B2 were detected in the plasma within 1 h after the consumption of the beverage. The susceptibility of erythrocytes to hemolysis was reduced significantly following the consumption of the beverages. The duration of the lag time, which reflects the capacity of cells to buffer free radicals, was increased. Consistent with the above, the purified flavonoids, epicatechin, catechin, Dimer B2 and the metabolite 3ʹ-O-methyl epicatechin, exhibited dose-dependent protection against AAPH-induced erythrocyte hemolysis at concentrations ranging from 2.5 to 20 μM. Erythrocytes from subjects consuming flavonoid-rich cocoa show reduced susceptibility to free radical-induced hemolysis (p < 0.05.

  9. Aquaporin-1-Mediated Effects of Low Level He-Ne Laser Irradiation on Human Erythrocytes

    Gang-Yue Luo

    2012-01-01

    Full Text Available The role of membrane aquaporin-1 (APQ-1 in the photobiomodulation (PBM on erythrocyte deformability will be studied in this paper with human dehydrated erythrocytes as echinocytic shape alterations lead to decreased cellular deformability. Human dehydrated erythrocytes were irradiated with low intensity He-Ne laser irradiation (LHNL at 0.9, 1.8, 2.7, and 4.4 mW/cm2 for 5, 15, and 30 min, respectively, and APQ-1 inhibitor, 0.2 μmol/L HgCl2, was used to study the role of APQ-1 in mediating PBM with LHNL at 4.4 mW/cm2 for 5 min. Comprehensive morphological parameters of an intact cell such as contact area, perimeter, roundness and erythrocyte elongation index (EEI were measured to characterize erythrocyte deformability with fast micro multi-channel spectrophotometer. It was observed that the dosage of LHNL improvement of the morphological parameters of dehydrated erythrocytes was morphological-parameter-dependent, but the Bunsen-Roscoe rule did not hold for roundness. The LHNL at 4.4 mW/cm2 for 5 min significantly improved the contact area (P<0.05 and EEI (P<0.05 of the dehydrated erythrocytes, but the improvement was significantly inhibited by 0.2 μmol/L HgCl2 (P<0.05. It was concluded that AQP-1 might mediate the effects of LHNL on erythrocyte deformability, which supports the membranotropic mechanism of PBM.

  10. Intracellular free calcium concentration and calcium transport in human erythrocytes of lead-exposed workers

    Quintanar-Escorza, M.A.; Gonzalez-Martinez, M.T.; Navarro, L.; Maldonado, M.; Arevalo, B.; Calderon-Salinas, J.V.

    2007-01-01

    Erythrocytes are the route of lead distribution to organs and tissues. The effect of lead on calcium homeostasis in human erythrocytes and other excitable cells is not known. In the present work we studied the effect of lead intoxication on the uptake and efflux (measured as (Ca 2+ -Mg 2+ )-ATPase activity) of calcium were studied in erythrocytes obtained from lead-exposed workers. Blood samples were taken from 15 workers exposed to lead (blood lead concentration 74.4 ± 21.9 μg/dl) and 15 non-exposed workers (9.9 ± 2 μg/dl). In erythrocytes of lead-exposed workers, the intracellular free calcium was 79 ± 13 nM, a significantly higher concentration (ANOVA, P 2+ -Mg 2+ )-ATPase activity. Lipid peroxidation was 1.7-fold higher in erythrocytes of lead-exposed workers as compared with control. The alteration on calcium equilibrium in erythrocytes is discussed in light of the toxicological effects in lead-exposed workers

  11. Antioxidant status of erythrocytes and their response to oxidative challenge in humans with argemone oil poisoning

    Babu, Challagundla K.; Khanna, Subhash K.; Das, Mukul

    2008-01-01

    Oxidative damage of biomolecules and antioxidant status in erythrocytes of humans from an outbreak of argemone oil (AO) poisoning in Kannauj (India) and AO intoxicated experimental animals was investigated. Erythrocytes of the dropsy patients and AO treated rats were found to be more susceptible to 2,2'-azobis (2-amidinopropane) dihydrochloride (AAPH) induced peroxidative stress. Significant decrease in RBC glutathione (GSH) levels (46, 63%) with concomitant enhancement in oxidized glutathione (172, 154%) levels was noticed in patients and AO intoxicated animals. Further, depletion of glutathione reductase (GR), glucose-6-phosphate dehydrogenase (G-6-PDH) and glutathione-S-transferase (GST) (42-52%) was observed in dropsy patients. Oxidation of erythrocyte membrane lipids and proteins was increased (120-144%) in patients and AO treated animals (112-137%) along with 8-OHdG levels in whole blood (180%) of dropsy patients. A significant reduction in α-tocopherol content (68%) was noticed in erythrocytes of dropsy patients and hepatic, plasma and RBCs of AO treated rats (59-70%) thereby indicating the diminished antioxidant potential to scavenge free radicals or the limited transport of α-tocopherol from liver to RBCs leading to enhanced oxidation of lipids and proteins in erythrocytes. These studies implicate an important role of erythrocyte degradation in production of anemia and breathlessness in epidemic dropsy

  12. Antioxidant capacity of Ugni molinae fruit extract on human erythrocytes: an in vitro study.

    Suwalsky, Mario; Avello, Marcia

    2014-08-01

    Ugni molinae is an important source of molecules with strong antioxidant activity widely used as a medicinal plant in Southern Chile-Argentina. Total phenol concentration from its fruit extract was 10.64 ± 0.04 mM gallic acid equivalents. Analysis by means of HPLC/MS indicated the presence of the anthocyanins cyanidin and peonidin, and the flavonol quercitin, all in glycosylated forms. Its antioxidant properties were assessed in human erythrocytes in vitro exposed to HClO oxidative stress. Scanning electron microscopy showed that HClO induced an alteration in erythrocytes from a normal shape to echinocytes; however, this change was highly attenuated in samples containing U. molinae extracts. It also had a tendency in order to reduce the hemolytic effect of HClO. In addition, X-ray diffraction experiments were performed in dimyristoylphosphatidylcholine (DMPC) and dimyristoylphosphatidylethanolamine bilayers, classes of lipids preferentially located in the outer and inner monolayers, respectively, of the human erythrocyte membrane. It was observed that U. molinae only interacted with DMPC. Results by fluorescence spectroscopy on DMPC large unilamellar vesicles and isolated unsealed human erythrocyte membranes also showed that it interacted with the erythrocyte membrane and DMPC. It is possible that the location of U. molinae components into the membrane outer monolayer might hinder the diffusion of HClO and of free radicals into cell membranes and the consequent decrease of the kinetics of free radical reactions.

  13. The influence of split doses of γ-radiation on human erythrocytes

    Koziczak, R.; Gonciarz, M.; Krokosz, A.; Szweda-Lewandowska, Z.

    2003-01-01

    Human erythrocyte suspensions in an isotonic Na-phosphate buffer, pH 7.4, of hematocrit of 2% were exposed under air to gamma radiation at a dose rate of 2.2 kGy. Erythrocytes were irradiated with single doses, and identical doses split into two fractions with an interval time of 3.5 h between following exposures. The obtained results indicated that the irradiation of enucleated human erythrocytes with split doses caused a reduction of hemolysis (2.4 times), a decrease in the level of damage to membrane lipids and the contents of MetHb, compared with identical single doses. However, the splitting of radiation doses did not change the level of damage to the membrane proteins, as was estimated with a maleimide spin label. The obtained results suggest that a decrease in the level of damage to lipids was related to a decrease in hemolysis. (author)

  14. Recognition of Human Erythrocyte Receptors by the Tryptophan-Rich Antigens of Monkey Malaria Parasite Plasmodium knowlesi.

    Kriti Tyagi

    Full Text Available The monkey malaria parasite Plasmodium knowlesi also infect humans. There is a lack of information on the molecular mechanisms that take place between this simian parasite and its heterologous human host erythrocytes leading to this zoonotic disease. Therefore, we investigated here the binding ability of P. knowlesi tryptophan-rich antigens (PkTRAgs to the human erythrocytes and sharing of the erythrocyte receptors between them as well as with other commonly occurring human malaria parasites.Six PkTRAgs were cloned and expressed in E.coli as well as in mammalian CHO-K1 cell to determine their human erythrocyte binding activity by cell-ELISA, and in-vitro rosetting assay, respectively.Three of six PkTRAgs (PkTRAg38.3, PkTRAg40.1, and PkTRAg67.1 showed binding to human erythrocytes. Two of them (PkTRAg40.1 and PkTRAg38.3 showed cross-competition with each other as well as with the previously described P.vivax tryptophan-rich antigens (PvTRAgs for human erythrocyte receptors. However, the third protein (PkTRAg67.1 utilized the additional but different human erythrocyte receptor(s as it did not cross-compete for erythrocyte binding with either of these two PkTRAgs as well as with any of the PvTRAgs. These three PkTRAgs also inhibited the P.falciparum parasite growth in in-vitro culture, further indicating the sharing of human erythrocyte receptors by these parasite species and the biological significance of this receptor-ligand interaction between heterologous host and simian parasite.Recognition and sharing of human erythrocyte receptor(s by PkTRAgs with human parasite ligands could be part of the strategy adopted by the monkey malaria parasite to establish inside the heterologous human host.

  15. Recognition of Human Erythrocyte Receptors by the Tryptophan-Rich Antigens of Monkey Malaria Parasite Plasmodium knowlesi.

    Tyagi, Kriti; Gupta, Deepali; Saini, Ekta; Choudhary, Shilpa; Jamwal, Abhishek; Alam, Mohd Shoeb; Zeeshan, Mohammad; Tyagi, Rupesh K; Sharma, Yagya D

    2015-01-01

    The monkey malaria parasite Plasmodium knowlesi also infect humans. There is a lack of information on the molecular mechanisms that take place between this simian parasite and its heterologous human host erythrocytes leading to this zoonotic disease. Therefore, we investigated here the binding ability of P. knowlesi tryptophan-rich antigens (PkTRAgs) to the human erythrocytes and sharing of the erythrocyte receptors between them as well as with other commonly occurring human malaria parasites. Six PkTRAgs were cloned and expressed in E.coli as well as in mammalian CHO-K1 cell to determine their human erythrocyte binding activity by cell-ELISA, and in-vitro rosetting assay, respectively. Three of six PkTRAgs (PkTRAg38.3, PkTRAg40.1, and PkTRAg67.1) showed binding to human erythrocytes. Two of them (PkTRAg40.1 and PkTRAg38.3) showed cross-competition with each other as well as with the previously described P.vivax tryptophan-rich antigens (PvTRAgs) for human erythrocyte receptors. However, the third protein (PkTRAg67.1) utilized the additional but different human erythrocyte receptor(s) as it did not cross-compete for erythrocyte binding with either of these two PkTRAgs as well as with any of the PvTRAgs. These three PkTRAgs also inhibited the P.falciparum parasite growth in in-vitro culture, further indicating the sharing of human erythrocyte receptors by these parasite species and the biological significance of this receptor-ligand interaction between heterologous host and simian parasite. Recognition and sharing of human erythrocyte receptor(s) by PkTRAgs with human parasite ligands could be part of the strategy adopted by the monkey malaria parasite to establish inside the heterologous human host.

  16. Radioprotective effect of antioxidants on human blood lymphocytes

    Wang Mingsuo; Gu Xuandi; Zhu Genbo; Feng Jixing; Su Liaoyuan

    1991-09-01

    By using an improved fluorometric method with 2-thiobarbituric acid (TBA) as fluorometric agent, the antiradiation effects of four kinds of antioxidants on 60 Co γ-ray irradiation inducing final products of lipid peroxides (LPO), i.e. malodialdehyde (MDA) content changes in human blood lymphocytes, were investigated with LPO value as an indicator. The results of the experiment were as following: (1)The radioprotective effect of exogenous antioxidants added to human blood lymphocytes on radiation-induced LPO damage of cellular membrane were remarkable; (2)The radioprotective beneficial sequences of four kinds of antioxidants were arranged like this: SOD > VE >VC, Se 4+ ; (3)Radioprotective effects of antioxidants on radiation-induced damage varied especially with the property of antioxidants, drug concentration, and pretreatment and monitoring time, etc., as well as irradiated dosage and various kinds of incubated cells. In addition, the mechanism of these antioxidants as radioprotectants on human blood lymphocytes is discussed in connection with LPO damage and radioprotection

  17. Regulation of hemoglobin AIc formation in human erythrocytes in vitro. Effects of physiologic factors other than glucose.

    Smith, R J; Koenig, R J; Binnerts, A; Soeldner, J S; Aoki, T T

    1982-01-01

    The formation of hemoglobin AIc was studied in intact human erythrocytes in vitro. Satisfactory methods were developed for maintaining erythrocytes under physiologic conditions for greater than 8 d with less than 10% hemolysis. Hemoglobin AIc levels were determined chromatographically on erythrocyte hemolysates after removal of reversible components by incubation for 6 h at 37 degree C. Hemoglobin AIc concentration was found to increase linearly with time during 8 d of incubation. The rate of...

  18. Labelling malaria-infected human erythrocytes with Tc-99m

    Garmelius-Larsson, B.; Pettersson, F.; Vogt, A.; Jonsson, C.

    2002-01-01

    Aim: Malaria is an old and a very common disease, especially in undeveloped countries. The malaria parasites infect the erythrocytes and the aim of this work was to label infected cells for future studies of their distribution and life span. Material and Method: With a commercial kit containing stannous fluoride and sodium medronate, which is used to label erythrocytes in vivo, in vitro and in vivo/vitro methods, we labelled the cells by using a modified method and a small volume, 5 - 50 microlitre, of packed cells. The cells were labelled with Tc-99m in the range of 60 - 1500 MBq. The kit was reconstituted with saline and the pH was adjusted to 7.0. The cells were incubated with 1 ml of the kitsolution in 37 0 C for 5 min. The remaining Sn-ions were reduced by adding NaOCl and then the solution was centrifuged.The supernantant was discarded and the Tc-99m was added to the precipitate and incubated 37 0 C for 20 min and then washed 3 times. This labelling procedure was performed on both infected and on non-infected cells. Results: Ten samples of cells have been labelled. The best labelling result was obtained using 7 - 20 MBq per 10 microlitre of packed cells. The labelling efficiency was, on average, 35%. Conclusion: It is possible to label both infected and non-infected cells in very small volumes. The cells were visually inspected in a microscope and were viable after labelling. Furthermore, the cell distribution was traced in vivo in an animal model by a gamma camera

  19. Expression of senescent antigen on erythrocytes infected with a knobby variant of the human malaria parasite Plasmodium falciparum

    Winograd, E.; Greenan, J.R.T.; Sherman, I.W.

    1987-01-01

    Erythrocytes infected with a knobby variant of Plasmodium falciparum selectively bind IgG autoantibodies in normal human serum. Quantification of membrane-bound IgG, by use of 125 I-labeled protein A, revealed that erythrocytes infected with the knobby variant bound 30 times more protein A than did noninfected erythrocytes; infection with a knobless variant resulted in less than a 2-fold difference compared with noninfected erythrocytes. IgG binding to knobby erythrocytes appeared to be related to parasite development, since binding of 125 I-labeled protein A to cells bearing young trophozoites (less than 20 hr after parasite invasion) was similar to binding to uninfected erythrocytes. By immunoelectron microscopy, the membrane-bound IgG on erythrocytes infected with the knobby variant was found to be preferentially associated with the protuberances (knobs) of the plasma membrane. The removal of aged or senescent erythrocytes from the peripheral circulation is reported to involve the binding of specific antibodies to an antigen (senescent antigen) related to the major erythrocyte membrane protein band 3. Since affinity-purified autoantibodies against band 3 specifically bound to the plasma membrane of erythrocytes infected with the knobby variant of P. falciparum, it is clear that the malaria parasite induces expression of senescent antigen

  20. Clotrimazole enhances lysis of human erythrocytes induced by t-BHP.

    Lisovskaya, Irene L; Shcherbachenko, Irina M; Volkova, Rimma I; Ataullakhanov, Fazoil I

    2009-08-14

    Clotrimazole (CLT) is an antifungal and antimalarial agent also effective as a Gardos channel inhibitor. In addition, CLT possesses antitumor properties. Recent data provide evidence that CLT forms a complex with heme (hemin), which produces a more potent lytic effect than heme alone. This study addressed the effect of CLT on the lysis of normal human erythrocytes induced by tert-butyl hydroperoxide (t-BHP). For the first time, it was shown that 10 microM CLT significantly enhanced the lytic effect of t-BHP on erythrocytes in both Ca(2+)-containing and Ca(2+)-free media, suggesting that the effect is not related to Gardos channels. CLT did not affect the rate of free radical generation, the kinetics of GSH degradation, methemoglobin formation and TBARS generation; therefore, we concluded that CLT does not cause additional oxidative damage to erythrocytes treated with t-BHP. It is tempted to speculate that CLT enhances t-BHP-induced changes in erythrocyte volume and lysis largely by forming a complex with hemin released during hemoglobin oxidation in erythrocytes: the CLT-hemin complex destabilizes the cell membrane more potently than hemin alone. If so, the effect of CLT on cell membrane damage during free-radical oxidation may be used to increase the efficacy of antitumor therapy.

  1. Inclusion bodies in loggerhead erythrocytes are associated with unstable hemoglobin and resemble human Heinz bodies.

    Basile, Filomena; Di Santi, Annalisa; Caldora, Mercedes; Ferretti, Luigi; Bentivegna, Flegra; Pica, Alessandra

    2011-08-01

    The aim of this study was to clarify the role of the erythrocyte inclusions found during the hematological screening of loggerhead population of the Mediterranean Sea. We studied the erythrocyte inclusions in blood specimens collected from six juvenile and nine adult specimens of the loggerhead turtle, Caretta caretta, from the Adriatic and Tyrrhenian Seas. Our study indicates that the percentage of mature erythrocytes containing inclusions ranged from 3 to 82%. Each erythrocyte contained only one round inclusion body. Inclusion bodies stained with May Grünwald-Giemsa show that their cytochemical and ultrastructure characteristics are identical to those of human Heinz bodies. Because Heinz bodies originate from the precipitation of unstable hemoglobin (Hb) and cause globular osmotic resistance to increase, we analyzed loggerhead Hb using electrophoresis and high-performance liquid chromatography to detect and quantitate Hb fractions. We also tested the resistance of Hb to alkaline pH, heat, isopropanol denaturation, and globular osmosis. Our hemogram results excluded the occurrence of any infection, which could be associated with an inclusion body, in all the specimens. Negative Feulgen staining indicated that the inclusion bodies are not derived from DNA fragmentation. We hypothesize that amino acid substitutions could explain why loggerhead Hb precipitates under normal physiologic conditions, forming Heinz bodies. The identification of inclusion bodies in loggerhead erythrocytes allow us to better understand the haematological characteristics and the physiology of these ancient reptiles, thus aiding efforts to conserve such an endangered species. Copyright © 2011 Wiley-Liss, Inc., A Wiley Company.

  2. Curcumin Protects -SH Groups and Sulphate Transport after Oxidative Damage in Human Erythrocytes

    Rossana Morabito

    2015-05-01

    Full Text Available Background/Aims: Erythrocytes, continuously exposed to oxygen pressure and toxic compounds, are sensitive to oxidative stress, namely acting on integral Band 3 protein, with consequences on cell membranes deformability and anion transport efficiency. The aim of the present investigation, conducted on human erythrocytes, is to verify whether curcumin (1 or 10µM, a natural compound with proved antioxidant properties, may counteract Band 3-mediated anion transport alterations due to oxidative stress. Methods: Oxidative conditions were induced by exposure to, alternatively, either 2 mM N-ethylmaleimide (NEM or pH-modified solutions (6.5 and 8.5. Rate constant for SO4= uptake and -SH groups estimation were measured to verify the effect of oxidative stress on anion transport efficiency and erythrocyte membranes. Results: After the exposure of erythrocytes to, alternatively, NEM or pH-modified solutions, a significant decrease in both rate constant for SO4= uptake and -SH groups was observed, which was prevented by curcumin, with a dose-dependent effect. Conclusions: Our results show that: i the decreased efficiency of anion transport may be due to changes in Band 3 protein structure caused by cysteine -SH groups oxidation, especially after exposure to NEM and pH 6.5; ii 10 µM Curcumin is effective in protecting erythrocytes from oxidative stress events at level of cell membrane transport.

  3. Study of the effect of dose-rate on radiation-induced damage to human erythrocytes

    Krokosz, Anita [Department of Molecular Biophysics, University of Lodz, Banacha 12/16, Lodz (Poland)]. E-mail: krokosz@biol.uni.lodz.pl; Koziczak, Renata [Department of Molecular Biophysics, University of Lodz, Banacha 12/16, Lodz (Poland); Gonciarz, Marta [Department of Molecular Biophysics, University of Lodz, Banacha 12/16, Lodz (Poland); Szweda-Lewandowska, Zofia [Department of Molecular Biophysics, University of Lodz, Banacha 12/16, Lodz (Poland)

    2006-01-15

    Human erythrocytes suspended in an isotonic Na-phosphate buffer, pH 7.4 (hematocrit of 2%) were irradiated with {gamma}-rays at three dose-rates of 66.7, 36.7, 25 Gy min{sup -1} in order to investigate the influence of the dose-rate on radiation-induced membrane damage, hemoglobin oxidation and loss of reduced glutathione. The obtained results showed that such processes as erythrocyte hemolysis, lipid and protein destruction depend on the radiation dose-rate. The parameter values describing these processes showed an inverse dose-rate effect.

  4. Study of the effect of dose-rate on radiation-induced damage to human erythrocytes

    Krokosz, Anita; Koziczak, Renata; Gonciarz, Marta; Szweda-Lewandowska, Zofia

    2006-01-01

    Human erythrocytes suspended in an isotonic Na-phosphate buffer, pH 7.4 (hematocrit of 2%) were irradiated with γ-rays at three dose-rates of 66.7, 36.7, 25 Gy min -1 in order to investigate the influence of the dose-rate on radiation-induced membrane damage, hemoglobin oxidation and loss of reduced glutathione. The obtained results showed that such processes as erythrocyte hemolysis, lipid and protein destruction depend on the radiation dose-rate. The parameter values describing these processes showed an inverse dose-rate effect

  5. The action of cobra venom phospholipase A2 isoenzymes towards intact human erythrocytes

    Roelofsen, B.; Sibenius Trip, M.; Verheij, H.M.; Zevenbergen, J.L.

    1980-01-01

    1. 1. Cobra venom phospholipase A2 from three different sources has been fractionated into different isoenzymes by DEAE ion-exchange chromatography. 2. 2. Treatment of intact human erythrocytes with the various isoenzymes revealed significant differences in the degree of phosphatidylcholine

  6. Alcohol and the calcium-dependent potassium transport of human erythrocytes

    Harris, R.A.; Caldwell, K.K.

    1985-01-01

    In vitro exposure of human red blood cells to ethanol (100 and 400 mM) was found to increase the initial rate of calcium-dependent potassium efflux through the red cell membrane. This effect of ethanol was apparently not due to an elevation of the intracellular free calcium but rather to a direct action of the drug on the transport process as, (1) intracellular calcium concentrations were tightly buffered with EGTA, (2) ethanol did not alter the efflux of 45 Ca from the cells, and (3) dantrolene, which has been proposed to counteract the effect of ethanol on intracellular calcium levels in the erythrocyte, did not inhibit the stimulatory action of ethanol. The efflux of potassium from erythrocytes obtained from chronic alcoholics was not different from that of erythrocytes from non-alcoholic individuals. The relationship of these findings to neuronal potassium transport is discussed

  7. Selective effects of alpha interferon on human T-lymphocyte subsets during mixed lymphocyte cultures

    Hokland, M; Hokland, P; Heron, I

    1983-01-01

    Mixed lymphocyte reaction (MLR) cultures of human lymphocyte subsets with or without the addition of physiological doses of human alpha interferon (IFN-alpha) were compared with respect to surface marker phenotypes and proliferative capacities of the responder cells. A selective depression on the T...... T4 cells and decreased numbers of T4 cells harvested from IFN MLRs (days 5-6 of culture). In contrast, it was shown that the T8 (cytotoxic/suppressor) subset in MLRs was either not affected or slightly stimulated by the addition of IFN. The depression of the T4 cells by IFN was accompanied...... by a decrease in the number of activated T cells expressing Ia antigens. On the other hand, IFN MLRs contained greater numbers of cells expressing the T10 differentiation antigen. In experiments with purified T-cell subsets the IFN effect was exerted directly on the T4 cells and not mediated by either T8...

  8. Radioprotective effect of flavonoid quercetin on human lymphocytic cells

    Siqueira, Williams N.; Melo, Larissa S.A.; Lima, Maíra V.; Luna Filho, Ricardo L.C.; Melo, Ana M.M.A.; Silva, Edvane B.

    2017-01-01

    Several substances of synthetic and natural origin have been studied in relation to their ability to protect the body from damage caused by ionizing radiation. Among these substances, quercetin has been shown to be a molecule of natural origin with high radioprotective potential due to its antioxidant properties. The objective of this study was to determine, in vitro, the radioprotective effect of quercetin on human lymphocytes exposed to gamma radiation. Blood was irradiated at the 2.5, 3.5 and 4.5 Gy doses and then lymphocyte culture with quercetin at preselected concentrations of 37.5 and 75 μM. Subsequently, slides were prepared for analysis and quantification of the metaphases present in lymphocyte cells. The results demonstrated that irradiated lymphocytes and later exposed to quercetin presented a lower number of chromosomal alterations compared to the control group which was irradiated and not exposed to quercetin. Therefore, the results suggest a radioprotective effect of flavonoid quercetin on human lymphocytes exposed, in vitro, to ionizing radiation

  9. Investigation of cytogenetic activity of radioprotectors in human lymphocyte culture

    Egiazaryan, S.V.; Arutyunyan, R.M.

    1977-01-01

    Studied are the effects of the F-11 and F-37 indene preparations on chromosome aberrations induced in lymphocyte culture of peripheral human blood by thioTEP. Investigation into the action of the substance in euqimolar concentrations has not shown their protective effect. Indene preparations did not change the spectrum of chromosome aberrations induced by thioTEP as well as did not increase the level of chromosome aberrations in lumphocyte culture of human peripheral human blood

  10. Genotoxic damage in cultured human peripheral blood lymphocytes ...

    Falaq Naz

    2012-06-29

    Jun 29, 2012 ... Genotoxic damage in cultured human peripheral blood lymphocytes of oral ... catechol estrogens and quinines, via redox reactions causes oxidative damage to .... volume was prepared for each donor. About, 0.8 ml of cell sus .... duce the adverse effects of OCs, such as the reduction in the estrogen content.

  11. Specific depletion of mature T lymphocytes from human bone marrow

    Geisler, C; Møller, J; Plesner, T

    1989-01-01

    An effective method for specific depletion of mature T lymphocytes from human bone marrow mononuclear cells (BMMC) with preservation of prethymic T cells and natural killer (NK) cells is presented. The BMMC were incubated with F101.01, a monoclonal antibody recognizing an epitope of the T...

  12. Resistance of human erythrocytes containing elevated levels of vitamin E to radiation-induced hemolysis

    Brown, M.A.

    1983-01-01

    Human erythrocytes were isolated from the blood of healthy donors and then incubated in the presence of suspensions of alpha-tocopherol for 30 min at 37 degrees C. Unabsorbed tocopherol was removed by centrifugation using several washes of isotonic phosphate-buffered saline. Washed erythrocytes were resuspended to 0.05%. Hct and exposed to hemolyzing doses of 60 Co gamma radiation, and hemolysis was monitored continuously by light scattering at 700 nm in a recording spectrophotometer. The extent of hemolysis with time was sigmoid and data analysis was carried out on the time taken for 50% hemolysis to occur (t50%). The vitamin E content of erythrocytes was significantly elevated by the incubation procedure and resulted in the cells exhibiting a significantly increased resistance to hemolysis as reflected by the extended t50% values. Oral supplementation of 500 IU of vitamin E per day to eight normal human subjects for a period of 16 days also resulted in their washed erythrocytes exhibiting a significant increase in resistance to radiation-induced hemolysis. When comparing vitamin E incubated cells with control cells, both the dose-reducing factor (DRF) and the time for 50% hemolysis quotient (Qt50%) were observed to increase with increasing radiation dose

  13. Functional and structural changes of human erythrocyte catalase induced by cimetidine: proposed model of binding.

    Yazdi, Fatemeh; Minai-Tehrani, Dariush; Jahngirvand, Mahboubeh; Almasirad, Ali; Mousavi, Zahra; Masoud, Masoudeh; Mollasalehi, Hamidreza

    2015-06-01

    In erythrocyte, catalase plays an important role to protect cells from hydrogen peroxide toxicity. Hydrogen peroxide is a byproduct compound which is produced during metabolic pathway of cells. Cimetidine, a histamine H2 receptor antagonist, is used for gastrointestinal tract diseases and prevents the extra release of gastric acid. In this study, the effect of cimetidine on the activity of human erythrocyte catalase was investigated. Erythrocytes were broken by hypotonic solution. The supernatant was used for catalase assay and kinetics study. Lineweaver-Burk plot was performed to determine the type of inhibition. The kinetics data revealed that cimetidine inhibited the catalase activity by mixed inhibition. The IC50 (1.54 μM) and Ki (0.45 μM) values of cimetidine determined that the drug was bound to the enzyme with high affinity. Circular dichroism and fluorescence measurement showed that the binding of cimetidine to the enzyme affected the content of secondary structure of the enzyme as well as its conformational changes. Docking studies were carried out to detect the site in which the drug was bound to the enzyme. Molecular modeling and energy calculation of the binding showed that the cyanoguanidine group of the drug connected to Asp59 via two hydrogen bonds, while the imidazole group of the drug interacted with Phe64 in the enzyme by a hydrophobic interaction. In conclusion, cimetidine could bind to human erythrocyte catalase, and its interaction caused functional and conformational changes in the enzyme.

  14. Kinetics of human lymphocyte division and chromosomal radiosensitivity

    Bianchi, N O; Bianchi, M S; Larramendy, M [Instituto Multidisciplinario de Biologia Celular, La Plata (Argentinia)

    1979-12-01

    Human blood from normal donors was irradiated with 200 R during the G/sub 0/ phase, and the X-ray sensitivity of early and late dividing lymphocytes in culture was expressed as percentage of induced dicentrics. Cells in first or subsequent divisions were individualized by BrdU-Giemsa techniques. Lymphocytes in the first division at 40, 44 and 72 h after the start of culture had a lower sensitivity to radiation than lymphocytes making their first division at 48, 52 and 56 h. It was observed that: (a) the combination of radiation followed by BrdU did not increase the clastoyenic action of X-rays, (b)X-rays in the dose and duration used in our cultures did not increase the frequency of SCEs, and (c) minor changes in culture conditions probably influenced the frequency of SCEs.

  15. Bifenthrin-induced oxidative stress in human erythrocytes in vitro and protective effect of selected flavonols.

    Sadowska-Woda, Izabela; Popowicz, Diana; Karowicz-Bilińska, Agata

    2010-03-01

    Bifenthrin is a synthetic pyrethroid with a broad spectrum of insecticidal and acaricidal activity used to control wide range of insect pests in a variety of applications. This investigation was designed to examine (1) bifenthrin as an inducer of oxidative stress in human erythrocytes in vitro through effects on catalase (CAT) and superoxide dismutase (SOD) activities, and (2) the role of the flavonoids quercetin (Q, 40 and 80microM) and rutin (R, 80microM) in alleviating the effects of bifenthrin. Erythrocytes were divided into portions. The first portion was incubated for 4h at 37 degrees C with different concentrations (0, 42.2, 211, 1055ppm) of bifenthrin. The other portions were preincubated with Q or R for 30min, followed incubation with bifenthrin for 4h. The influence of solvent (ethanol) was also checked on the parameters studied. Malondialdehyde (MDA) concentrations, CAT and SOD activities were measured in all treatment portions of erythrocytes. Our results demonstrated that bifenthrin-induced oxidative stress causes enhanced lipid peroxidation and decreased antioxidative enzyme activities in human peripheral blood. R pretreated erythrocytes were protected against the increase of MDA induced by bifenthrin. Q (80microM) and R pretreated erythrocytes were protected against the inhibition of CAT activity induced by bifenthrin. The protective action against the inhibition of SOD activity of Q was greater than that of R at the same concentration. These results suggest that Q and R may play a role in reducing bifenthrin-induced oxidative stress in vitro. Copyright (c) 2009 Elsevier Ltd. All rights reserved.

  16. Membrane-Wrapping Contributions to Malaria Parasite Invasion of the Human Erythrocyte

    Dasgupta, Sabyasachi; Auth, Thorsten; Gov, Nir S.; Satchwell, Timothy J.; Hanssen, Eric; Zuccala, Elizabeth S.; Riglar, David T.; Toye, Ashley M.; Betz, Timo; Baum, Jake; Gompper, Gerhard

    2014-01-01

    The blood stage malaria parasite, the merozoite, has a small window of opportunity during which it must successfully target and invade a human erythrocyte. The process of invasion is nonetheless remarkably rapid. To date, mechanistic models of invasion have focused predominantly on the parasite actomyosin motor contribution to the energetics of entry. Here, we have conducted a numerical analysis using dimensions for an archetypal merozoite to predict the respective contributions of the host-parasite interactions to invasion, in particular the role of membrane wrapping. Our theoretical modeling demonstrates that erythrocyte membrane wrapping alone, as a function of merozoite adhesive and shape properties, is sufficient to entirely account for the first key step of the invasion process, that of merozoite reorientation to its apex and tight adhesive linkage between the two cells. Next, parasite-induced reorganization of the erythrocyte cytoskeleton and release of parasite-derived membrane can also account for a considerable energetic portion of actual invasion itself, through membrane wrapping. Thus, contrary to the prevailing dogma, wrapping by the erythrocyte combined with parasite-derived membrane release can markedly reduce the expected contributions of the merozoite actomyosin motor to invasion. We therefore propose that invasion is a balance between parasite and host cell contributions, evolved toward maximal efficient use of biophysical forces between the two cells. PMID:24988340

  17. Human T Lymphocytes Are Permissive for Dengue Virus Replication.

    Silveira, Guilherme F; Wowk, Pryscilla F; Cataneo, Allan H D; Dos Santos, Paula F; Delgobo, Murilo; Stimamiglio, Marco A; Lo Sarzi, Maria; Thomazelli, Ana Paula F S; Conchon-Costa, Ivete; Pavanelli, Wander R; Antonelli, Lis R V; Báfica, André; Mansur, Daniel S; Dos Santos, Claudia N Duarte; Bordignon, Juliano

    2018-05-15

    Dengue virus (DV) infection can cause either a self-limiting flu-like disease or a threatening hemorrhage that may evolve to shock and death. A variety of cell types, such as dendritic cells, monocytes, and B cells, can be infected by DV. However, despite the role of T lymphocytes in the control of DV replication, there remains a paucity of information on possible DV-T cell interactions during the disease course. In the present study, we have demonstrated that primary human naive CD4 + and CD8 + T cells are permissive for DV infection. Importantly, both T cell subtypes support viral replication and secrete viable virus particles. DV infection triggers the activation of both CD4 + and CD8 + T lymphocytes, but preactivation of T cells reduces the susceptibility of T cells to DV infection. Interestingly, the cytotoxicity-inducing protein granzyme A is highly secreted by human CD4 + but not CD8 + T cells after exposure to DV in vitro Additionally, using annexin V and polycaspase assays, we have demonstrated that T lymphocytes, in contrast to monocytes, are resistant to DV-induced apoptosis. Strikingly, both CD4 + and CD8 + T cells were found to be infected with DV in acutely infected dengue patients. Together, these results show that T cells are permissive for DV infection in vitro and in vivo , suggesting that this cell population may be a viral reservoir during the acute phase of the disease. IMPORTANCE Infection by dengue virus (DV) causes a flu-like disease that can evolve to severe hemorrhaging and death. T lymphocytes are important cells that regulate antibody secretion by B cells and trigger the death of infected cells. However, little is known about the direct interaction between DV and T lymphocytes. Here, we show that T lymphocytes from healthy donors are susceptible to infection by DV, leading to cell activation. Additionally, T cells seem to be resistant to DV-induced apoptosis, suggesting a potential role as a viral reservoir in humans. Finally, we show

  18. Facilitated uptake of a bioactive metabolite of maritime pine bark extract (pycnogenol into human erythrocytes.

    Max Kurlbaum

    Full Text Available Many plant secondary metabolites exhibit some degree of biological activity in humans. It is a common observation that individual plant-derived compounds in vivo are present in the nanomolar concentration range at which they usually fail to display measurable activity in vitro. While it is debatable that compounds detected in plasma are not the key effectors of bioactivity, an alternative hypothesis may take into consideration that measurable concentrations also reside in compartments other than plasma. We analysed the binding of constituents and the metabolite δ-(3,4-dihydroxy-phenyl-γ-valerolactone (M1, that had been previously detected in plasma samples of human consumers of pine bark extract Pycnogenol, to human erythrocytes. We found that caffeic acid, taxifolin, and ferulic acid passively bind to red blood cells, but only the bioactive metabolite M1 revealed pronounced accumulation. The partitioning of M1 into erythrocytes was significantly diminished at higher concentrations of M1 and in the presence of glucose, suggesting a facilitated transport of M1 via GLUT-1 transporter. This concept was further supported by structural similarities between the natural substrate α-D-glucose and the S-isomer of M1. After cellular uptake, M1 underwent further metabolism by conjugation with glutathione. We present strong indication for a transporter-mediated accumulation of a flavonoid metabolite in human erythrocytes and subsequent formation of a novel glutathione adduct. The physiologic role of the adduct remains to be elucidated.

  19. Physical and Chemical Processes and the Morphofunctional Characteristics of Human Erythrocytes in Hyperglycaemia

    Victor V. Revin

    2017-08-01

    Full Text Available Background: This study examines the effect of graduated hyperglycaemia on the state and oxygen-binding ability of hemoglobin, the correlation of phospholipid fractions and their metabolites in the membrane, the activity of proteolytic enzymes and the morphofunctional state of erythrocytes.Methods: Conformational changes in the molecule of hemoglobin were determined by Raman spectroscopy. The structure of the erythrocytes was analyzed using laser interference microscopy (LIM. To determine the activity of NADN-methemoglobinreductase, we used the P.G. Board method. The degree of glycosylation of the erythrocyte membranes was determined using a method previously described by Felkoren et al. Lipid extraction was performed using the Bligh and Dyer method. Detection of the phospholipids was performed using V. E. Vaskovsky method.Results: Conditions of hyperglycaemia are characterized by a low affinity of hemoglobin to oxygen, which is manifested as a parallel decrease in the content of hemoglobin oxyform and the growth of deoxyform, methemoglobin and membrane-bound hemoglobin. The degree of glycosylation of membrane proteins and hemoglobin is high. For example, in the case of hyperglycaemia, erythrocytic membranes reduce the content of all phospholipid fractions with a simultaneous increase in lysoforms, free fatty acids and the diacylglycerol (DAG. Step wise hyperglycaemia in incubation medium and human erythrocytes results in an increased content of peptide components and general trypsin-like activity in the cytosol, with a simultaneous decreased activity of μ-calpain and caspase 3.Conclusions: Metabolic disorders and damage of cell membranes during hyperglycaemia cause an increase in the population of echinocytes and spherocytes. The resulting disorders are accompanied with a high probability of intravascular haemolysis.

  20. Neisseria meningitidis and Escherichia coli are protected from leukocyte phagocytosis by binding to erythrocyte complement receptor 1 in human blood

    Brekke, O. L.; Hellerud, B. C.; Christiansen, D.

    2011-01-01

    The initial interaction of Gram-negative bacteria with erythrocytes and its implications on leukocyte phagocytosis and oxidative burst in human whole blood were examined. Alexa-labeled Escherichia coli, wild-type H44/76 N. meningitidis and the H44/76lpxA lipopolysaccharide (LPS)-deficient mutant...... antagonist (C5aRa) and a complement receptor 1 (CR1)-blocking antibody (3D9) were examined. Most bacteria (80%) immediately bound to erythrocytes. The binding gradually declined over time, with a parallel increase in phagocytosis. Complement inhibition with compstatin reduced erythrocyte binding...... and bacterial C3 opsonization. In contrast, the C5aRa efficiently reduced phagocytosis, but did not affect the binding of bacteria to erythrocytes. The anti-CR1 blocking mAb dose-dependently reduced bacterial binding to erythrocytes to nil, with subsequent increased phagocytosis and oxidative burst. LPS had...

  1. Radiolabeled Humanized Anti-CD3 Monoclonal Antibody Visilizumab for Imaging Human T-Lymphocytes

    Malviya, Gaurav; D'Alessandria, Calogero; Bonanno, Elena; Vexler, Vladimir; Massari, Roberto; Trotta, Carlo; Scopinaro, Francesco; Dierckx, Rudi; Signore, Alberto

    2009-01-01

    Visilizumab is an IgG(2) humanized monoclonal antibody (mAb) characterized by non-Fc gamma R binding and specific to the CD3 antigen, expressed on more than 95% of circulating resting T-lymphocytes and on activated T-lymphocytes homing in inflamed tissues. We hypothesized that the use of a

  2. Production of C-reactive protein by human lymphocytes

    Kuta, A.E.; Baum, L.L.

    1986-01-01

    C-reactive protein (CRP) is a major acute phase serum protein in humans; it is detectable at very high concentrations during infection and tissue trauma. This protein is a pentame composed of five identical, 21,500 MW subunits. CRP is detectable on the surface of approximately 4% of normal peripheral blood lymphocytes (PBL). CRP binds its physiological ligands in a Ca ++ dependent manner; removal of Ca ++ does not alter the expression of CRP on the lymphocyte surface. Recently, investigators in this laboratory reported substantial inhibition of natural killer cell (NK) activity with anti-CRP antibodies. The following studies were undertaken to determine the origin of surface-CRP (S-CRP) found on normal PBL. Cells were incubated in methionine-free DMEM supplemented with 35 S-methionine. Cells were lysed and subjected to immunoprecipitation with anti-CRP and Staphylococcus aureus; immunoprecipitates were analyzed by SDS-PAGE and autoradiography. Data presented here suggested that lymphocytes, in particular, LGL produce small amounts of CRP and express it on their surface. Lymphocytes do not appear to secrete CRP since no CRP could be detected in culture supernatants. In addition, preliminary evidence indicates that peripheral blood monocytes produce no detectable CRP. Present studies utilizing Northern blot analysis are underway in order to detect CRP-mRNA

  3. Survival of human lymphocytes after exposure to densely ionizing radiations

    Madhvanath, U.; Raju, M.R.; Kelly, L.S.

    1976-01-01

    Interphase death of human blood lymphocytes cultured in vitro was studied after exposure to 60 Co gamma rays and to accelerated ions of 1 H, 4 He, 7 Li, 11 B, 12 C, 20 Ne, 40 Ar, and π - meson beam under aerobic conditions. Exposures were also conducted under hypoxic conditions with 60 Co gamma rays, 4 He, 7 Li, and 12 C ion beams. Time course of interphase death was followed for 6 days after irradiation. Percent survivals were determined by using the trypan blue exclusion method. Survival curves at 5 days postirradiation were exponential for all radiations studied. These observations indicate that the production of interphase death of lymphocytes by densely ionizing radiations follows a pattern similar to that observed with colony-forming mammalian cells. However, the reproductive capacity of the latter cells is impaired with maximum effectiveness at energy densities associated with 220 keV/μm for the beam conditions used in this investigation. The much lower energy densities required to kill a lymphocyte suggest that a sensitive structure other than DNA may be responsible for the production of lymphocyte death, perhaps the membranes. The calculated inactivation cross sections for high-LET radiations above 650 keV/μm yielded values larger than the actual cell dimensions. It appears that contributions from delta rays become appreciable in this system at these LET's

  4. Cytogenetic evaluation of Fansidar on human lymphocyte chromosomes in vitro.

    Praveen, Nuzhat; Saifi, Muheet Alam; Shadab, G G H A

    2011-01-01

    Fansidar is a fixed combination of two antimalarial agents a diaminopyrimidine (Pyrimethamine) and a sulphonamide (Sulphadoxine) in the ratio 1:20- that have been used extensively worldwide for the treatment of Chloroquine resistant Plasmodium falciparum malaria, toxoplasmosis and Pneumocystis carinii pneumonia in patients with the acquired immunodeficiency syndrome. This study examined the effect of Fansidar on chromosomes in human lymphocyte culture. Fansidar was added to peripheral blood lymphocyte cultures in vitro at four different concentrations: 5,15, 25 and 50 microl in the ratio 1:20, 3:60, 5:100 and 10:200 microg ml(-1). Result shows that this drug induces moderate increase in the frequency of gaps, breaks and rearrangements. Therefore it can be concluded that Fansidar has moderate clastogenic effect on human chromosomes in vitro.

  5. Human alpha-fetoprotein and prostaglandins suppress human lymphocyte transformation by different mechanisms

    Yachnin, S.; Lester, E.P.

    1979-01-01

    The capacity of human alpha-fetoprotein (HAFP) to suppress human lymphocyte transformation is well established, although some investigators have reported negative results in their efforts to demonstrate this phenomenon. This discrepancy may reside in the fact that not all isolates of HAFP are potent inhibitors of lymphocyte transformation and that the immunosuppressive potency of various HAFP isolates may be correlated with the proportion of certain negatively charged HAFP isomers which they contain. The possibility was considered that noncovalent binding of low-molecular-weight, negatively charged molecules might be partially responsible. Since fatty acids, including certain prostaglandins (PG), are capable of binding to a partly related serum protein, namely, human serum albumin, and since certain prostaglandins are known to be potent suppressors of human lymphocyte transformation, a study was undertaken of the role which prostaglandins might play in HAFP-induced suppression of human lymphocyte transformation

  6. Cosmic radiation induced chromosomal aberrations in human lymphocytes

    De Angelis, G.; Facius, R.; Reitz, G.

    2003-01-01

    Since decades, elevated frequencies of dicentric chromosomes (DIC) in human lymphocytes have successfully been used as a biological dosimeter in cases of acute, often accidental exposures to ionizing radiation. As long as duration and time lags after exposure are small compared to the lifetime of DIC, their frequencies can also be used to assess doses from protracted, chronic irradiation. E.g., within the substantial range of uncertainties, the frequencies of DIC observed in cosmonauts are compatible with the frequencies expected from doses of low and high LET radiation to which they were exposed in low earth orbit (LEO). On the other hand, frequencies of DIC detected in lymphocytes of civilian aviation crewmembers rarely correlate with the doses accumulated all along their professional career. For such long duration exposures with relatively low induction rates, the concomitant decay of DIC frequencies due to the removal during exposure of lymphocytes carrying DIC has to be taken into account. We present temporal profiles of frequencies of DIC during the exposure calculated with a model of exponential decay of DIC for some scenarios of chronic exposure to cosmic radiation. E.g., even after a 'heavily' shielded Mars mission, the expected frequencies of DIC in lymphocytes of astronauts will be 10 to 40 times higher than the terrestrial control levels. For air flight personnel we calculated the time profiles of frequencies of DIC in lymphocytes of a 'typical' pilot, a male cabin attendant and a female cabin attendant whose professional radiation exposures were recalculated for the actual flight routes flown during their entire flight career as recorded in detailed duty logs. These results demonstrate that experimental (epidemiological) studies concerning DIC in air or space flight personnel must explicitly take into consideration the temporal exposure profiles in the prospective study population and that the point in time at which blood samples are to be drawn must

  7. Morphological and Molecular Descriptors of the Developmental Cycle of Babesia divergens Parasites in Human Erythrocytes.

    Ingrid Rossouw

    2015-05-01

    Full Text Available Human babesiosis, especially caused by the cattle derived Babesia divergens parasite, is on the increase, resulting in renewed attentiveness to this potentially life threatening emerging zoonotic disease. The molecular mechanisms underlying the pathophysiology and intra-erythrocytic development of these parasites are poorly understood. This impedes concerted efforts aimed at the discovery of novel anti-babesiacidal agents. By applying sensitive cell biological and molecular functional genomics tools, we describe the intra-erythrocytic development cycle of B. divergens parasites from immature, mono-nucleated ring forms to bi-nucleated paired piriforms and ultimately multi-nucleated tetrads that characterizes zoonotic Babesia spp. This is further correlated for the first time to nuclear content increases during intra-erythrocytic development progression, providing insight into the part of the life cycle that occurs during human infection. High-content temporal evaluation elucidated the contribution of the different stages to life cycle progression. Moreover, molecular descriptors indicate that B. divergens parasites employ physiological adaptation to in vitro cultivation. Additionally, differential expression is observed as the parasite equilibrates its developmental stages during its life cycle. Together, this information provides the first temporal evaluation of the functional transcriptome of B. divergens parasites, information that could be useful in identifying biological processes essential to parasite survival for future anti-babesiacidal discoveries.

  8. Effects of an angelica extract on human erythrocyte aggregation, deformation and osmotic fragility.

    Wang, X; Wei, L; Ouyang, J P; Muller, S; Gentils, M; Cauchois, G; Stoltz, J F

    2001-01-01

    In Chinese traditional medicine, angelica is widely used for its known clinical effects of ameliorating blood microcirculation. But the mechanism of these beneficial effects still remains unclear. In this work the rheological behaviour of human erythrocytes treated by angelica was studied in vitro. Normal RBCs incubated with an angelica extract at different concentrations (5, 10 or 20 mg/ml) for 60 min at 37 degrees C and then their aggregation, deformation and osmotic fragility were measured with different recently developed optical techniques, namely Erythroaggregometer (Regulest, Florange, France), LORCA (Mechatronics, Amsterdam) and Fragilimeter (Regulest, Florange, France). Experimental results show that angelica (20 mg/ml) significantly decreased normal RBCs' aggregation speed (p<0.01) and could inhibit the hyperaggregability caused by dextran 500. However, the strength of normal RBCs aggregates were not influenced by angelica. When a calcium ionophore A23187 (1.9 microM) was used to harden cell membrane, angelica (20 mg/ml) could significantly (p<0.01) protect erythrocytes against the loss of their deformability even it had no effects on normal RBCs deformation. Finally angelica (5 and 10 mg/ml) decreased significantly (p<0.01) normal RBCs osmotic fragility. In conclusion angelica plays a rheologically active role on human erythrocytes, and this study suggests a possible mechanism for angelica's positive effects against certain cardiovascular diseases.

  9. 31P-NMR study of human pyrimidine 5'-nucleotidase deficient erythrocytes

    Higaki, Tsuyoshi; Kagimoto, Tadashi; Nagata, Koichi; Tanase, Sumio; Morino, Yoshimasa; Takatsuki, Kiyoshi

    1982-01-01

    Metabolic disorder of nucleotides in human pyrimidine 5'-nucleotidase (P5N) deficient erythrocytes was studied by 31 P-NMR with high resolution. Identification by combination of high-speed liquid chromatography revealed two-fold increases from the normal in the spectra in the α-, β- and γ-zones of nucleoside triphosphates of P5N deficient erythrocytes, 2,3-diphosphoglycerate shifted to the 0.3 ppm low magnetic field and signals of NAD and UDP-sugars(s) in the diphosphodiester zone. These results were obtained from the 31 P-NMR spectrum about one hour after blood sampling, indicating the high utility of this NMR for the diagnosis of P5N deficiency. (Chiba, N.)

  10. Influence of magnesium sulfate on HCO3/Cl transmembrane exchange rate in human erythrocytes.

    Chernyshova, Ekaterina S; Zaikina, Yulia S; Tsvetovskaya, Galina A; Strokotov, Dmitry I; Yurkin, Maxim A; Serebrennikova, Elena S; Volkov, Leonid; Maltsev, Valeri P; Chernyshev, Andrei V

    2016-03-21

    Magnesium sulfate (MgSO4) is widely used in medicine but molecular mechanisms of its protection through influence on erythrocytes are not fully understood and are considerably controversial. Using scanning flow cytometry, in this work for the first time we observed experimentally (both in situ and in vitro) a significant increase of HCO3(-)/Cl(-) transmembrane exchange rate of human erythrocytes in the presence of MgSO4 in blood. For a quantitative analysis of the obtained experimental data, we introduced and verified a molecular kinetic model, which describes activation of major anion exchanger Band 3 (or AE1) by its complexation with free intracellular Mg(2+) (taking into account Mg(2+) membrane transport and intracellular buffering). Fitting the model to our in vitro experimental data, we observed a good correspondence between theoretical and experimental kinetic curves that allowed us to evaluate the model parameters and to estimate for the first time the association constant of Mg(2+) with Band 3 as KB~0.07mM, which is in agreement with known values of the apparent Mg(2+) dissociation constant (from 0.01 to 0.1mM) that reflects experiments on enrichment of Mg(2+) at the inner erythrocyte membrane (Gunther, 2007). Results of this work partly clarify the molecular mechanisms of MgSO4 action in human erythrocytes. The method developed allows one to estimate quantitatively a perspective of MgSO4 treatment for a patient. It should be particularly helpful in prenatal medicine for early detection of pathologies associated with the risk of fetal hypoxia. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. In vitro effects of the anti-Alzheimer drug memantine on the human erythrocyte membrane and molecular models

    Zambrano, Pablo; Suwalsky, Mario; Villena, Fernando; Jemiola-Rzeminska, Malgorzata; Strzalka, Kazimierz

    2017-01-01

    Memantine is a NMDA antagonist receptor clinically used for treating Alzheimer's disease. NMDA receptors are present in the human neurons and erythrocyte membranes. The aim of the present study was to investigate the effects of memantine on human erythrocytes. With this purpose, the drug was developed to in vitro interact with human red cells and bilayers built-up of dimyristoylphosphatidylcholine (DMPC) and dimyristoylphosphatidylethanolamine (DMPE). The latter represent lipids respectively present in both outer and inner monolayers of the red cell membrane. Results obtained by scanning electron microscopy (SEM) showed that memantine changed the normal biconcave shape of red cells to cup-shaped stomatocytes. According to the bilayer-couple hypothesis the drug intercalated into the inner monolayer of the erythrocyte membrane. Experimental results obtained by X-ray diffraction on multibilayers of DMPC and DMPE, and by differential scanning calorimetry on multilamellar vesicles indicated that memantine preferentially interacted with DMPC in a concentration-dependent manner. Thus, it can be concluded that in the low therapeutic plasma concentration of circa 1 μM memantine is located in NMDA receptor channel without affecting the erythrocyte shape. However, at higher concentrations, once the receptors became saturated excess of memantine molecules (20 μM) would interact with phosphoinositide lipids present in the inner monolayer of the erythrocyte membrane inducing the formation of stomatocytes. However, 40–50 μM memantine was required to interact with isolated phosphatidylcholine bilayers. - Highlights: • The interaction of memantine with human erythrocytes and lipid bilayers were assessed. • Memantine induced morphological changes to human erythrocytes. • Memantine interacted with classes of phospholipids present in the erythrocyte membrane. • Results support the hypothesis that memantine interacts with NMDA receptors.

  12. Effects of diethylene glycol butyl ether and butoxyethoxyacetic acid on rat and human erythrocytes.

    Udden, M M

    2005-03-28

    The toxicity of diethylene glycol butyl ether (DGBE), and its principal metabolite, butoxyethoxyacetic acid (BEAA), were assessed in vitro for rat and human red blood cells. Rat erythrocytes showed evidence of mild hemolysis when exposed to BEAA at concentrations of 5 or 10 mM for 4 h. BEAA treated rat red blood cells also showed evidence of sub-hemolytic damage: increased spherocytosis, a shift in distribution of cell size to larger cells, a significant increase in mean cellular volume, and a decrease in cellular deformability. However, DGBE had no effect on rat red blood cell morphology, cell size, hemolysis or deformability. There was no hemolysis when human red blood cells were exposed to DGBE or BEAA at the same concentrations. No changes in mean cellular volume, distribution of cell size, or morphologic appearance of human red blood cells were observed. No evidence for decreased deformability of human red blood cells exposed to DGBE or BEAA was found. In conclusion, BEAA has weak hemolytic activity and sub-hemolytic effects in vitro on rat erythrocytes, which is consistent with the finding of mild hemolysis when the parent compound DGBE is administered to rats by gavage. The absence of hemolysis or sub-hemolytic damage when human red blood cells were exposed to BEAA or DGBE in vitro indicates that it is unlikely that hemolysis will occur as a result of human exposure to DGBE.

  13. Plasmodium falciparum Adhesins Play an Essential Role in Signalling and Activation of Invasion into Human Erythrocytes.

    Wai-Hong Tham

    2015-12-01

    Full Text Available The most severe form of malaria in humans is caused by the protozoan parasite Plasmodium falciparum. The invasive form of malaria parasites is termed a merozoite and it employs an array of parasite proteins that bind to the host cell to mediate invasion. In Plasmodium falciparum, the erythrocyte binding-like (EBL and reticulocyte binding-like (Rh protein families are responsible for binding to specific erythrocyte receptors for invasion and mediating signalling events that initiate active entry of the malaria parasite. Here we have addressed the role of the cytoplasmic tails of these proteins in activating merozoite invasion after receptor engagement. We show that the cytoplasmic domains of these type 1 membrane proteins are phosphorylated in vitro. Depletion of PfCK2, a kinase implicated to phosphorylate these cytoplasmic tails, blocks P. falciparum invasion of red blood cells. We identify the crucial residues within the PfRh4 cytoplasmic domain that are required for successful parasite invasion. Live cell imaging of merozoites from these transgenic mutants show they attach but do not penetrate erythrocytes implying the PfRh4 cytoplasmic tail conveys signals important for the successful completion of the invasion process.

  14. The Effect of Covalently-Attached ATRP-Synthesized Polymers on Membrane Stability and Cytoprotection in Human Erythrocytes.

    Clafshenkel, William P; Murata, Hironobu; Andersen, Jill; Creeger, Yehuda; Koepsel, Richard R; Russell, Alan J

    2016-01-01

    Erythrocytes have been described as advantageous drug delivery vehicles. In order to ensure an adequate circulation half-life, erythrocytes may benefit from protective enhancements that maintain membrane integrity and neutralize oxidative damage of membrane proteins that otherwise facilitate their premature clearance from circulation. Surface modification of erythrocytes using rationally designed polymers, synthesized via atom-transfer radical polymerization (ATRP), may further expand the field of membrane-engineered red blood cells. This study describes the fate of ATRP-synthesized polymers that were covalently attached to human erythrocytes as well as the effect of membrane engineering on cell stability under physiological and oxidative conditions in vitro. The biocompatible, membrane-reactive polymers were homogenously retained on the periphery of modified erythrocytes for at least 24 hours. Membrane engineering stabilized the erythrocyte membrane and effectively neutralized oxidative species, even in the absence of free-radical scavenger-containing polymers. The targeted functionalization of Band 3 protein by NHS-pDMAA-Cy3 polymers stabilized its monomeric form preventing aggregation in the presence of the crosslinking reagent, bis(sulfosuccinimidyl)suberate (BS3). A free radical scavenging polymer, NHS-pDMAA-TEMPO˙, provided additional protection of surface modified erythrocytes in an in vitro model of oxidative stress. Preserving or augmenting cytoprotective mechanisms that extend circulation half-life is an important consideration for the use of red blood cells for drug delivery in various pathologies, as they are likely to encounter areas of imbalanced oxidative stress as they circuit the vascular system.

  15. The Effect of Covalently-Attached ATRP-Synthesized Polymers on Membrane Stability and Cytoprotection in Human Erythrocytes.

    William P Clafshenkel

    Full Text Available Erythrocytes have been described as advantageous drug delivery vehicles. In order to ensure an adequate circulation half-life, erythrocytes may benefit from protective enhancements that maintain membrane integrity and neutralize oxidative damage of membrane proteins that otherwise facilitate their premature clearance from circulation. Surface modification of erythrocytes using rationally designed polymers, synthesized via atom-transfer radical polymerization (ATRP, may further expand the field of membrane-engineered red blood cells. This study describes the fate of ATRP-synthesized polymers that were covalently attached to human erythrocytes as well as the effect of membrane engineering on cell stability under physiological and oxidative conditions in vitro. The biocompatible, membrane-reactive polymers were homogenously retained on the periphery of modified erythrocytes for at least 24 hours. Membrane engineering stabilized the erythrocyte membrane and effectively neutralized oxidative species, even in the absence of free-radical scavenger-containing polymers. The targeted functionalization of Band 3 protein by NHS-pDMAA-Cy3 polymers stabilized its monomeric form preventing aggregation in the presence of the crosslinking reagent, bis(sulfosuccinimidylsuberate (BS3. A free radical scavenging polymer, NHS-pDMAA-TEMPO˙, provided additional protection of surface modified erythrocytes in an in vitro model of oxidative stress. Preserving or augmenting cytoprotective mechanisms that extend circulation half-life is an important consideration for the use of red blood cells for drug delivery in various pathologies, as they are likely to encounter areas of imbalanced oxidative stress as they circuit the vascular system.

  16. A simple solid-phase radioimmunoassay for the measurement of IgG secreted in vitro by human lymphocytes

    Romagnani, S.; Prete, G.F. del; Giudizi, G.M.; Almerigogna, F.; Ricci, M.

    1979-01-01

    A radioimmunoassay is described for measuring IgG, based on the ability of immunoglobulins of this class to inhibit the binding of radioiodinated staphylococcal protein A to IgG linked to a solid phase. The solid phase is represented by ox erythrocytes coated with anti-ox erthrocyte rabbit IgG, a reagent used for detecting cells equipped with receptors for the Fc fragment of IgG. By this assay the IgG secreted in vitro by human peripheral blood lymphocytes stimulated with PWM and those present in samples of very diluted human sera were measured. It was found that the assay is a very rapid, simple and and reproducible procedure for the detection of IgG immunoglobulin at the nanogram level. (Auth.)

  17. An in vitro study on the antioxidant capacity of usnic acid on human erythrocytes and molecular models of its membrane.

    Suwalsky, M; Jemiola-Rzeminska, M; Astudillo, C; Gallardo, M J; Staforelli, J P; Villena, F; Strzalka, K

    2015-11-01

    Usnic acid (UA) has been associated with chronic diseases through its antioxidant action. Its main target is the cell membrane; however, its effect on that of human erythrocytes has been scarcely investigated. To gain insight into the molecular mechanisms of the interaction between UA and cell membranes human erythrocytes and molecular models of its membrane have been utilized. Dimyristoylphosphatidylcholine (DMPC) and dimyristoylphosphatidylethanolamine (DMPE) were chosen as representative of phospholipid classes located in the outer and inner monolayers of the erythrocyte membrane, respectively. Results by X-ray diffraction showed that UA produced structural perturbations on DMPC and DMPE bilayers. DSC studies have indicated that thermotropic behavior of DMPE was most strongly distorted by UA than DMPC, whereas the latter is mainly affected on the pretransition. Scanning electron (SEM) and defocusing microscopy (DM) showed that UA induced alterations to erythrocytes from the normal discoid shape to echinocytes. These results imply that UA molecules were located in the outer monolayer of the erythrocyte membrane. Results of its antioxidant properties showed that UA neutralized the oxidative capacity of HClO on DMPC and DMPE bilayers; SEM, DM and hemolysis assays demonstrated the protective effect of UA against the deleterious oxidant effects of HClO upon human erythrocytes. Copyright © 2015 Elsevier B.V. All rights reserved.

  18. Cytogenetic effects of tritium incorporated into DNA of human lymphocytes

    Beno, M [Inst. of Preventive and Clinical Medicine, 83301 Bratislava (Slovakia)

    1996-12-31

    In the reported in vitro experiments the numbers of chromosomal aberrations (CA) in correlation to the physical dose as assessed by determining the specific radioactivity of DNA have been followed in vitro human lymphocytes from adult donors. Lymphocytes from healthy adult donors of age from 20 to 59 of both sexes (24 males and 20 females) were isolated from blood by centrifugation. After washing the cells were irradiated from tritium incorporated during in vitro incubation in phytohemagglutinin containing medium with tritium labelled thymidine. Slides for standard CA counting have been done from every sample 48 hours after the begin cultivation. The CA were counted in at least 200 metaphases on each slide. Parallel samples of lymphocytes served for preparation smears for autoradiography to determine the labeling index. Other parallel samples were used for the determination of tritium concentration in DNA by the diphenylamine method, as well as determination of the specific radioactivity in lymphocyte DNA by scintillation counting. The dose absorbed in DNA was estimated using the conversion factor implicating that 37 kBq of tritium uniformly distributed per gram of tissue of unit density delivers a dose rate of 121.4 {sup m}i{sup G}y/hour. The contamination of cells by precursors of nucleic acids - like tritiated thymidine - causes an uneven distribution of doses in the cell population. A proportion of the population of cells remains unlabelled. The dose-response curve is flat showing signs of loss of heavily damaged cells and signs of repair of damage. Both these signs are based on the nature of biological processes which lead to internal contamination of cells and to expression of effects in terms of numbers of CA. (J.K.) 5 figs., 4 refs.

  19. Genotoxic evaluation of terbinafine in human lymphocytes in vitro.

    Tolomeotti, Danielle; de Castro-Prado, Marialba Avezum Alves; de Sant'Anna, Juliane Rocha; Martins, Ana Beatriz Tozzo; Della-Rosa, Valter Augusto

    2015-01-01

    Terbinafine is an antimycotic drug usually used against several superficial fungal infections and with a potential application in the treatment of human cancers. Since to date there are few data on the genotoxic effects of terbinafine in mammalian cells, current study evaluated the potential genotoxic of such antifungal agent in cultured human peripheral blood lymphocytes. Terbinafine was used at the peak plasma concentration (1.0 μg/ml) and in four additional concentrations higher than the human plasmatic peak (5.0 μg/ml, 25.0 μg/ml, 50.0 μg/ml and 100.0 μg/ml). Chromosomal aberrations (CA), sister chromatid exchanges (SCE), micronuclei (MN), nucleoplasmic bridges (NP) and nuclear buds (NB) were scored as genetic endpoints. In all analysis no significant differences (α = 0.05, Kruskal-Wallis test) were observed. Complementary criterion adopted to obtain the final response in cytogenetic agreed with statistical results. Therefore, results of this study showed that terbinafine neither induced CA, SCE, MN, NP and NB nor affected significantly mitotic, replication and cytokinesis-block proliferation indices in any of the tested concentrations. It may be assumed that terbinafine was not genotoxic or cytotoxic to cultured human peripheral blood lymphocytes in our experimental conditions.

  20. Effects of 415 MHz frequency on human lymphocyte genome

    Garaj-Vrhovac, V.; Fucic, A.; Kubelka, D.; Vojvodic, S.

    1996-01-01

    The continuously increasing use of artificial sources of electromagnetic radiation in industry and medicine has been accompanied in everyday life with telecommunication systems which is followed with great interest in possible hazardous effects of this type of radiation. The interesting applications of mobile telecommunications and the use of cellular phones are of topic interest. Numerous cytogenetic investigations are focused on the effects of microwave radiation from mobile communications frequency of 450 and 950 MHz on isolated cells in vitro. The aim of this work was to investigate the effects of microwaves from mobile telephone frequencies on human peripheral blood lymphocytes cultured in vitro. (author)

  1. Effect of oral proguanil on human lymphocyte proliferation

    Bygbjerg, Ib Christian; Flachs, H

    1986-01-01

    In vitro studies have indicated that the antifolates pyrimethamine [4, 6] and cycloguanil (the active metabolite of proguanil) suppress the proliferation of stimulated human lymphocytes; proguanil has no effect [2]. During the early growth phase of the cells, 14C-thymidine (14C-TdR) incorporation...... is increased by pyrimethamine and cycloguanil, reflecting blockage of endogenous TdR synthesis [3]. Proguanil (Paludrine) is increasingly being used for malaria prophylaxis. It is considered the most innocuous of the antimalarials currently employed. Since nothing is known about the effect of oral proguanil...

  2. Changes in haematology, plasma biochemistry and erythrocyte ...

    The results suggest that maintaining wild birds in captivity for a prolonged period could be stressful as shown by the heterophil/lymphocytes ratio and reduced erythrocyte osmotic resistance, and could lead to decreases in erythrocyte parameters and muscle wasting. Keywords: Haematological parameters, erythrocyte ...

  3. Ultrastructure changes produced by the action of uranyl acetate on the human erythrocyte in vitro

    Wyatt, J H

    1975-06-01

    Human erythrocytes exposed in vitro to low concentrations of uranyl ions are immediately changed in shape to stomatocytes. Electron microscope examination demonstrates that cellular damage is confined to the plasma membrane. Endocytosis of the cell membrane produces groups of inside out membrane-lined vesicles within the cell; lipid from the membrane enters the cell, giving rise to intracellular myelin figures, and breaks are seen in the cell membrane. It is proposed that the lipid fraction of the cell membrane is the primary target for damage by uranyl ions.

  4. Ultrastructure changes produced by the action of uranyl acetate on the human erythrocyte in vitro

    Wyatt, J.H.

    1975-06-01

    Human erythrocytes exposed in vitro to low concentrations of uranyl ions are immediately changed in shape to stomatocytes. Electron microscope examination demonstrates that cellular damage is confined to the plasma membrane. Endocytosis of the cell membrane produces groups of inside out membrane-lined vesicles within the cell; lipid from the membrane enters the cell, giving rise to intracellular myelin figures, and breaks are seen in the cell membrane. It is proposed that the lipid fraction of the cell membrane is the primary target for damage by uranyl ions. (author)

  5. Adaptation of the genetically tractable malaria pathogen Plasmodium knowlesi to continuous culture in human erythrocytes

    Moon, Robert

    2012-12-24

    Research into the aetiological agent of the most widespread form of severe malaria, Plasmodium falciparum, has benefitted enormously from the ability to culture and genetically manipulate blood-stage forms of the parasite in vitro. However, most malaria outside Africa is caused by a distinct Plasmodium species, Plasmodium vivax, and it has become increasingly apparent that zoonotic infection by the closely related simian parasite Plasmodium knowlesi is a frequent cause of life-threatening malaria in regions of southeast Asia. Neither of these important malarial species can be cultured in human cells in vitro, requiring access to primates with the associated ethical and practical constraints. We report the successful adaptation of P. knowlesi to continuous culture in human erythrocytes. Human-adapted P. knowlesi clones maintain their capacity to replicate in monkey erythrocytes and can be genetically modified with unprecedented efficiency, providing an important and unique model for studying conserved aspects of malarial biology as well as species-specific features of an emerging pathogen.

  6. Adaptation of the genetically tractable malaria pathogen Plasmodium knowlesi to continuous culture in human erythrocytes

    Moon, Robert; Hall, Joanna M.; Rangkuti, Farania; Ho, YungShwen; Almond, Neil M.; Mitchell, Graham Howard; Pain, Arnab; Holder, Anthony A.; Blackman, Michael J.

    2012-01-01

    Research into the aetiological agent of the most widespread form of severe malaria, Plasmodium falciparum, has benefitted enormously from the ability to culture and genetically manipulate blood-stage forms of the parasite in vitro. However, most malaria outside Africa is caused by a distinct Plasmodium species, Plasmodium vivax, and it has become increasingly apparent that zoonotic infection by the closely related simian parasite Plasmodium knowlesi is a frequent cause of life-threatening malaria in regions of southeast Asia. Neither of these important malarial species can be cultured in human cells in vitro, requiring access to primates with the associated ethical and practical constraints. We report the successful adaptation of P. knowlesi to continuous culture in human erythrocytes. Human-adapted P. knowlesi clones maintain their capacity to replicate in monkey erythrocytes and can be genetically modified with unprecedented efficiency, providing an important and unique model for studying conserved aspects of malarial biology as well as species-specific features of an emerging pathogen.

  7. Effects of cobalt-60 ionizing radiation on human erythrocyte and its membrane proteins

    Amancio, Francisco Fernandes

    1998-01-01

    Ionizing radiation has several uses, as sterilization and radiotherapy, by its effects on living beings. recently, it has been used, at relatively lower doses (25 Gy), on blood for transfusions, mainly to eliminate undesirable graft host reactions, for use in multi transfused or immunocompromised patients. Here, we study the effect of larger doses of cobalt-60 ionizing radiation (25-1600 Gy) on human erythrocytes, by cytometric, physiologic, biochemical and immunological methods, looking for its effects and its detection. The red cells presented a clear dose-dependent increase in this volume, when irradiated in doses higher than 200 Gy, more significant in stored blood, but without hemolysis. Osmotic fragility was increased only after irradiation of more than 400 Gy. By ektacytometry, there was a lower deformability of irradiated red cells, at low stress (0.3 Pa), similar to capillary flow, but without alteration in higher stress (3 Pa), found in cardiac chambers. By SDS-PAGE, it was demonstrated that irradiated isolated erythrocyte membranes had aggregation of spectrin molecules, and decay of bands with lower molecular mass. This effect could be attributed to the radiation-induced hydroxyl radical, by specific scavenger studies. Those modifications were both antigenic and immunogenic in experimental animals, and the induced antibodies recognizes, by ELISA and immunoblot, both native or irradiated membrane proteins. They recognize rather irradiated whole erythrocyte than native ones, by hemagglutination, indirect immunofluorescence or flow cytometry assays. Our data suggests that human red cells could be irradiated at higher doses than those usually employed, with possible effect on other contaminant pathogens, without loss of viability of its use in transfusions. After improvements, irradiation induced epitopes detection could be a new tool in biological dosimetry. (author)

  8. Human lymphocyte polymorphisms detected by quantitative two-dimensional electrophoresis

    Goldman, D.; Merril, C.R.

    1983-01-01

    A survey of 186 soluble lymphocyte proteins for genetic polymorphism was carried out utilizing two-dimensional electrophoresis of 14 C-labeled phytohemagglutinin (PHA)-stimulated human lymphocyte proteins. Nineteen of these proteins exhibited positional variation consistent with independent genetic polymorphism in a primary sample of 28 individuals. Each of these polymorphisms was characterized by quantitative gene-dosage dependence insofar as the heterozygous phenotype expressed approximately 50% of each allelic gene product as was seen in homozygotes. Patterns observed were also identical in monozygotic twins, replicate samples, and replicate gels. The three expected phenotypes (two homozygotes and a heterozygote) were observed in each of 10 of these polymorphisms while the remaining nine had one of the homozygous classes absent. The presence of the three phenotypes, the demonstration of gene-dosage dependence, and our own and previous pedigree analysis of certain of these polymorphisms supports the genetic basis of these variants. Based on this data, the frequency of polymorphic loci for man is: P . 19/186 . .102, and the average heterozygosity is .024. This estimate is approximately 1/3 to 1/2 the rate of polymorphism previously estimated for man in other studies using one-dimensional electrophoresis of isozyme loci. The newly described polymorphisms and others which should be detectable in larger protein surveys with two-dimensional electrophoresis hold promise as genetic markers of the human genome for use in gene mapping and pedigree analyses

  9. Selective toxicity of persian gulf sea cucumber holothuria parva on human chronic lymphocytic leukemia b lymphocytes by direct mitochondrial targeting.

    Salimi, Ahmad; Motallebi, Abbasali; Ayatollahi, Maryam; Seydi, Enayatollah; Mohseni, Ali Reza; Nazemi, Melika; Pourahmad, Jalal

    2017-04-01

    Natural products isolated from marine environment are well known for their pharmacodynamic potential in diversity of disease treatments such as cancer or inflammatory conditions. Sea cucumbers are one of the marine animals of the phylum Echinoderm. Many studies have shown that the sea cucumber contains antioxidants and anti-cancer compounds. Chronic lymphocytic leukemia (CLL) is a disease characterized by the relentless accumulation of CD5 + B lymphocytes. CLL is the most common leukemia in adults, about 25-30% of all leukemias. In this study B lymphocytes and their mitochondria (cancerous and non-cancerous) were obtained from peripheral blood of human subjects and B lymphocyte cytotoxicity assay, and caspase 3 activation along with mitochondrial upstream events of apoptosis signaling including reactive oxygen species (ROS) production, collapse of mitochondrial membrane potential (MMP) and mitochondrial swelling were determined following the addition of Holothuria parva extract to both cancerous and non-cancerous B lymphocytes and their mitochondria. Our in vitro finding showed that mitochondrial ROS formation, MMP collapse, and mitochondrial swelling and cytochrome c release were significantly (P < 0.05) increased after addition of different concentrations of H. parva only in cancerous BUT NOT normal non-cancerous mitochondria. Consistently, different concentrations of H. parva significantly (P < 0.05) increased cytotoxicity and caspase 3 activation only in cancerous BUT NOT normal non-cancerous B lymphocytes. These results showed that H. parva methanolic extract has a selective mitochondria mediated apoptotic effect on chronic lymphocytic leukemia B lymphocytes hence may be promising in the future anticancer drug development for treatment of CLL. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 1158-1169, 2017. © 2016 Wiley Periodicals, Inc.

  10. T-lymphocyte dependency of B-lymphocyte blastogenic response to phytomitogens

    Han, T.; Dadey, B.

    1978-01-01

    Human peripheral blood T and B lymphocytes were separated by a method based on the stable rosette formation of T lymphocytes with neuraminidase-treated sheep erythrocytes, followed by centrifugation over a Ficoll-Hypaque gradient. Monocytes were isolated from the T-depleted B lymphocyte preparation by allowing the monocytes to ingest iron particles and by subsequent centrifugation over a Ficoll-Hypaque gradient. The T lymphocytes responded extremely well to PHA and very well to PWM, while the B lymphocytes were unresponsive to either PHA or PWM. However, when the B lymphocytes were cultured together with irradiated autologous or allogeneic T lymphocytes (1 : 1,1:2 or 1 : 4 ratio), both PHA and PWM became mitogenic to B lymphocytes. Irradiated T lymphocytes alone did not respond to either PHA or PWM, indicating that the 3 H-thymidine incorporation seen in the mixed-cell culture was due to the activation of unirradiated B lymphocytes. The B lymphocytes failed to respond to these phytomitogens in the presence of lower concentrations of irradiated T lymphocytes. The monocytes were found to be incapable of helping the B lymphocytes to respond to PHA or PWM. (author)

  11. Nitrosylated hemoglobin levels in human venous erythrocytes correlate with vascular endothelial function measured by digital reactive hyperemia.

    Irina I Lobysheva

    Full Text Available Impaired nitric oxide (NO-dependent endothelial function is associated with the development of cardiovascular diseases. We hypothesized that erythrocyte levels of nitrosylated hemoglobin (HbNO-heme may reflect vascular endothelial function in vivo. We developed a modified subtraction method using Electron Paramagnetic Resonance (EPR spectroscopy to identify the 5-coordinate α-HbNO (HbNO concentration in human erythrocytes and examined its correlation with endothelial function assessed by peripheral arterial tonometry (PAT. Changes in digital pulse amplitude were measured by PAT during reactive hyperemia following brachial arterial occlusion in a group of healthy volunteers (50 subjects. Erythrocyte HbNO levels were measured at baseline and at the peak of hyperemia. We digitally subtracted an individual model EPR signal of erythrocyte free radicals from the whole EPR spectrum to unmask and quantitate the HbNO EPR signals.Mean erythrocyte HbNO concentration at baseline was 219+/-12 nmol/L (n = 50. HbNO levels and reactive hyperemia (RH indexes were higher in female (free of contraceptive pills than male subjects. We observed a dynamic increase of HbNO levels in erythrocytes isolated at 1-2 min of post-occlusion hyperemia (120+/-8% of basal levels; post-occlusion HbNO levels were correlated with basal levels. Both basal and post-occlusion HbNO levels were significantly correlated with reactive hyperemia (RH indexes (r = 0.58; P<0.0001 for basal HbNO.The study demonstrates quantitative measurements of 5-coordinate α-HbNO in human venous erythrocytes, its dynamic physiologic regulation and correlation with endothelial function measured by tonometry during hyperemia. This opens the way to further understanding of in vivo determinants of NO bioavailability in human circulation.

  12. Grape extract protects against γ-radiation-induced membrane damage strains of human erythrocytes

    Das, Subir Kumar

    2017-01-01

    The membrane integrity of circulating red blood cells (RBCs) is compromised by the deleterious actions of γ-radiation in humans. Grapes are the richest source of antioxidants due to presence of potentially bioactive phytochemicals. The objective of the present study was to assess the radioprotective actions of grape extracts against the γ-radiation-induced membrane permeability of human erythrocytes. The scavenging activities in seeds of grape in DPPH, hydrogen peroxide and hydroxyl radicals, were higher than skin or pulp of different cultivars. Grape extracts also showed appreciable extent of total antioxidant capacity and effective antihemolytic action. Grape extracts significantly ameliorated the γ-radiation-induced increase of the levels of thiobarbituric acid-reactive substances (TBARS, an index of lipid peroxidation) in the RBC membrane ghosts. Stored blood showed higher levels of K + ion as compared to the normal blood which was elevated by γ-radiation. Membrane ATPase was inhibited by the exposure to γ-radiation.Treatment of RBCs with the grape extracts prior to the exposure of γ-radiation significantly mitigated these changes in the erythrocyte membranes caused by the lower dose of radiation (4 Gy). (author)

  13. Selective radiolabeling and isolation of the hydrophobic membrane-binding domain of human erythrocyte acetylcholinesterase

    Roberts, W.L.; Rosenberry, T.L.

    1986-01-01

    The hydrophobic, membrane-binding domain of purified human erythrocyte acetylcholinesterase was labeled with the photoactivated reagent 3-(trifluoromethyl)-3-(m-[ 125 I]iodophenyl)diazirine. The radiolabel was incorporated when the enzyme was prepared in detergent-free aggregates, in detergent micelles, or in phospholipid liposomes, but the highest percentage of labeling occurred in the detergent-free aggregates. Papain digestion of the enzyme released the hydrophobic domain, and polyacrylamide gel electrophoresis in sodium dodecyl sulfate or gel exclusion chromatography demonstrated that the label was localized exclusively in the cleaved hydrophobic domain fragment. This fragment was purified in a three-step procedure. Digestion was conducted with papain attached to Sepharose CL-4B, and the supernatant was adsorbed to acridinium affinity resin to remove the hydrophilic enzyme fragment. The nonretained fragment associated with Triton X-100 micelles was then chromatographed on Sepharose CL-6B, and finally detergent was removed by chromatography on Sephadex LH-60 in an ethanol-formic acid solvent. The fragment exhibited an apparent molecular weight of 3100 on the Sephadex LH-60 column when compared with peptide standards. However, amino acid analysis of the purified fragment revealed only 1 mol each of histidine and glycine per mole of fragment in contrast to the 25-30 mole of amino acids expected on the basis of the molecular weight estimate. This result suggests a novel non-amino acid structure for the hydrophobic domain of human erythrocyte acetylcholinesterase

  14. Effect of pyrimethamine and sulphadoxine on human lymphocyte proliferation

    Bygbjerg, I C; Odum, Niels; Theander, T G

    1986-01-01

    The in vitro effect of pyrimethamine (PYR) on human blood mononuclear cells stimulated with phytohaemagglutinin (PHA), pokeweed mitogen (PWM) and purified protein derivative of tuberculin (PPD) was studied by 14C-thymidine incorporation, by cell counting and by total DNA estimation. PYR in concen......The in vitro effect of pyrimethamine (PYR) on human blood mononuclear cells stimulated with phytohaemagglutinin (PHA), pokeweed mitogen (PWM) and purified protein derivative of tuberculin (PPD) was studied by 14C-thymidine incorporation, by cell counting and by total DNA estimation. PYR...... in concentrations 10 times higher than serum values obtained in clinical practice inhibited lymphocyte proliferation irreversibly. PYR in concentrations corresponding to clinical practice quickly and irreversibly suppressed the proliferation of PWM-stimulated cells, and more slowly the proliferation of PPD...

  15. An Improved 2-Dimensional Gel Electrophoresis Method for Resolving Human Erythrocyte Membrane Proteins.

    Kumar, Manoj; Singh, Rajendra; Meena, Anil; Patidar, Bhagwan S; Prasad, Rajendra; Chhabra, Sunil K; Bansal, Surendra K

    2017-01-01

    The 2-dimensional gel electrophoresis (2-DE) technique is widely used for the analysis of complex protein mixtures extracted from biological samples. It is one of the most commonly used analytical techniques in proteomics to study qualitative and quantitative protein changes between different states of a cell or an organism (eg, healthy and diseased), conditionally expressed proteins, posttranslational modifications, and so on. The 2-DE technique is used for its unparalleled ability to separate thousands of proteins simultaneously. The resolution of the proteins by 2-DE largely depends on the quality of sample prepared during protein extraction which increases results in terms of reproducibility and minimizes protein modifications that may result in artifactual spots on 2-DE gels. The buffer used for the extraction and solubilization of proteins influences the quality and reproducibility of the resolution of proteins on 2-DE gel. The purification by cleanup kit is another powerful process to prevent horizontal streaking which occurs during isoelectric focusing due to the presence of contaminants such as salts, lipids, nucleic acids, and detergents. Erythrocyte membrane proteins serve as prototypes for multifunctional proteins in various erythroid and nonerythroid cells. In this study, we therefore optimized the selected major conditions of 2-DE for resolving various proteins of human erythrocyte membrane. The modification included the optimization of conditions for sample preparation, cleanup of protein sample, isoelectric focusing, equilibration, and storage of immobilized pH gradient strips, which were further carefully examined to achieve optimum conditions for improving the quality of protein spots on 2-DE gels. The present improved 2-DE analysis method enabled better detection of protein spots with higher quality and reproducibility. Therefore, the conditions established in this study may be used for the 2-DE analysis of erythrocyte membrane proteins for

  16. The effects of chemical and radioactive properties of Tl-201 on human erythrocyte glucose 6-phosphate dehydrogenase activity

    Sahin, Ali; Senturk, Murat; Ciftci, Mehmet; Varoglu, Erhan; Kufrevioglu, Omer Irfan

    2010-01-01

    Aim: The inhibitory effects of thallium-201 ( 201 Tl) solution on human erythrocyte glucose 6-phosphate dehydrogenase (G6PD) activity were investigated. Methods: For this purpose, erythrocyte G6PD was initially purified 835-fold at a yield of 41.7% using 2',5'-Adenosine diphosphate sepharose 4B affinity gel chromatography. The purification was monitored by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, which showed a single band for the final enzyme preparation. The in vitro and in vivo effects of the 201 Tl solution including Tl + , Fe +3 and Cu +2 metals and the in vitro effects of the radiation effect of the 201 Tl solution and non-radioactive Tl + , Fe +3 and Cu +2 metals on human erythrocyte G6PD enzyme were studied. Enzyme activity was determined with the Beutler method at 340 nm using a spectrophotometer. All purification procedures were carried out at +4 deg. C. Results: 201 Tl solution and radiation exposure had inhibitory effects on the enzyme activity. IC 50 value of 201 Tl solution was 36.86 μl ([Tl + ]: 0.0036 μM, [Cu +2 ]: 0.0116 μM, [Fe +3 ]: 0.0132 μM), of human erythrocytes G6PD. Seven human patients were also used for in vivo studies of 201 Tl solution. Furthermore, non-radioactive Tl + , Fe +3 and Cu +2 were found not to have influenced the enzyme in vitro. Conclusion: Human erythrocyte G6PD activity was inhibited by exposure for up to 10 minutes to 0.057 mCi/kg 201 Tl solution. It was detected in in vitro and in vivo studies that the human erythrocyte G6PD enzyme is inhibited due to the radiation effect of 201 Tl solution.

  17. Reproducible microtechnique for measuring stimulation of human lymphocytes by phytohemagglutinin

    Willard, K.E.; Lloyd, E.L.

    1977-01-01

    Methods based on tritiated thymidine incorporation were used for studies on the blastogenic transformation of human lymphocytes by phytohemagglutinin (PHA) in vitro. A stimulation index was calculated as the ratio of the radioactivity measured in lymphocytes to which PHA had been added to that in similar samples from which PHA was omitted. The stimulation indices have been shown to be reproducible to within 10 percent for the same individuals sampled at different times. The maximum mitotic indices for normal control subjects varied from 249 to 340. Seven to 11 different concentrations of PHA were used with each blood sample tested. The maximum index occurred, for most samples, at concentrations of PHA between 0.0625 μl and 1.0 μl/well. A systematic decrease in the maximum mitotic indices was found with increasing age in the range tested (19 to 58 years). Measurements of the single radium case 03 to 416, aged 70, with a residual body burden of 1.0 μCi 226 Ra gave a maximum value for the mitotic index of 44 at a concentration of 0.25 μl/well. This was a factor of 5 less than the value expected from our normal control subjects

  18. Vincristine-induced bystander effect in human lymphocytes

    Testi, Serena; Azzarà, Alessia; Giovannini, Caterina; Lombardi, Sara [Unità di Genetica, Dipartimento di Biologia, Pisa University, Via Derna 1, 56126 Pisa (Italy); Piaggi, Simona [Dipartimento di Ricerca Traslazionale e delle Nuove Tecnologie in Medicina e Chirurgia, Pisa University, Via Savi 10, 56126 Pisa (Italy); Facioni, Maria Sole [Unità di Genetica, Dipartimento di Biologia, Pisa University, Via Derna 1, 56126 Pisa (Italy); Scarpato, Roberto, E-mail: roberto.scarpato@unipi.it [Unità di Genetica, Dipartimento di Biologia, Pisa University, Via Derna 1, 56126 Pisa (Italy); Research Center of Nutraceuticals and Food for Health, University of Pisa, Pisa (Italy)

    2016-07-15

    Highlights: • We studied whether or not vincristine induced a bystander response in human lymphocytes. • Vincristine significantly increased MN frequencies in mononucleated recipient cells. • ROS or soluble proteins (IL-32 and TGF-β) may account for the observed response. - Abstract: Bystander effect is a known radiobiological effect, widely described using ionizing radiations and which, more recently, has also been related to chemical mutagens. In this study, we aimed to assess whether or not a bystander response can be induced in cultured human peripheral lymphocytes by vincristine, a chemotherapeutic mutagen acting as spindle poison, and by mitomycin-C, an alkylating agent already known to induce this response in human lymphoblastoid cells. Designing a modified ad hoc protocol for the cytokinesis blocked micronucleus (MN) assay, we detected the presence of a dose-dependent bystander response in untreated cultures receiving the conditioned medium (CM) from mitomycin-C (MMC) or vincristine (VCR) treated cultures. In the case of MMC, MN frequencies, expressed as micronucleated binucleates, were: 13.5 ± 1.41 at 6 μM, 22 ± 2.12 at 12 μM or 28.25 ± 5.13 at 15 μM vs. a control value of 4.75 ± 1.59. MN levels for VCR, expressed as micronucleated mononucleates were: 2.75 ± 0.88 at 0.0 μM, 27.25 ± 2.30 at 0.4 μM, 46.25 ± 1.94 at 0.8 μM, 98.25 ± 7.25 at 1.6 μM. To verify that no mutagen residual was transferred to recipient cultures together with the CM, we evaluated MN levels in cultures receiving the medium immediately after three washings following the chemical treatment (unconditioned medium). We further confirmed these results using a cell-mixing approach where untreated lymphocytes were co-cultured with donor cells treated with an effect-inducing dose of MMC or VCR. A distinct production pattern of both reactive oxygen species and soluble mediator proteins by treated cells may account for the differences observed in the manifestation of the

  19. Vincristine-induced bystander effect in human lymphocytes

    Testi, Serena; Azzarà, Alessia; Giovannini, Caterina; Lombardi, Sara; Piaggi, Simona; Facioni, Maria Sole; Scarpato, Roberto

    2016-01-01

    Highlights: • We studied whether or not vincristine induced a bystander response in human lymphocytes. • Vincristine significantly increased MN frequencies in mononucleated recipient cells. • ROS or soluble proteins (IL-32 and TGF-β) may account for the observed response. - Abstract: Bystander effect is a known radiobiological effect, widely described using ionizing radiations and which, more recently, has also been related to chemical mutagens. In this study, we aimed to assess whether or not a bystander response can be induced in cultured human peripheral lymphocytes by vincristine, a chemotherapeutic mutagen acting as spindle poison, and by mitomycin-C, an alkylating agent already known to induce this response in human lymphoblastoid cells. Designing a modified ad hoc protocol for the cytokinesis blocked micronucleus (MN) assay, we detected the presence of a dose-dependent bystander response in untreated cultures receiving the conditioned medium (CM) from mitomycin-C (MMC) or vincristine (VCR) treated cultures. In the case of MMC, MN frequencies, expressed as micronucleated binucleates, were: 13.5 ± 1.41 at 6 μM, 22 ± 2.12 at 12 μM or 28.25 ± 5.13 at 15 μM vs. a control value of 4.75 ± 1.59. MN levels for VCR, expressed as micronucleated mononucleates were: 2.75 ± 0.88 at 0.0 μM, 27.25 ± 2.30 at 0.4 μM, 46.25 ± 1.94 at 0.8 μM, 98.25 ± 7.25 at 1.6 μM. To verify that no mutagen residual was transferred to recipient cultures together with the CM, we evaluated MN levels in cultures receiving the medium immediately after three washings following the chemical treatment (unconditioned medium). We further confirmed these results using a cell-mixing approach where untreated lymphocytes were co-cultured with donor cells treated with an effect-inducing dose of MMC or VCR. A distinct production pattern of both reactive oxygen species and soluble mediator proteins by treated cells may account for the differences observed in the manifestation of the

  20. In vitro sensitization of human lymphocytes to a myeloma cell-related antigen

    Whitson, M.E.; Griffin, G.D.; Novelli, G.D.; Solomon, A.

    1981-01-01

    Peripheral blood lymphocytes from normal human donors were cocultivated with cells from two established human multiple myeloma cell lines, RPMI 8226 and K-737, and with lymphoblastoid cells from a third B cell line, RAMM. After a comparison of three methods of lymphocyte sensitization, a 6-day incubation protocol with equal numbers of normal lymphocytes and mitomycin C-treated tumor cells was selected. Cells fom the RPMI 8226 myeloma line stimulated the differentiation of lymphocytes into cytotoxic effector cells as measured by 51 Cr release from labeled target cells. The RPMI 8226-sensitized lymphocytes were cytotoxic for myeloma cells (RPMI 8226 and K-737) and for lymphoblastoid cells (RAMM) but not for cells from human lung tumor lines (A549, A427, MB9812), a breast carcinoma line (ALAB), a normal diploid fibroblast line (HSBP), or normal lymphocytes

  1. In vitro sensitization of human lymphocytes to a myeloma cell-related antigen

    Whitson, M.E. (Univ. of South Carolina, Columbia); Griffin, G.D.; Novelli, G.D.; Solomon, A.

    1981-01-01

    Peripheral blood lymphocytes from normal human donors were cocultivated with cells from two established human multiple myeloma cell lines, RPMI 8226 and K-737, and with lymphoblastoid cells from a third B cell line, RAMM. After a comparison of three methods of lymphocyte sensitization, a 6-day incubation protocol with equal numbers of normal lymphocytes and mitomycin C-treated tumor cells was selected. Cells fom the RPMI 8226 myeloma line stimulated the differentiation of lymphocytes into cytotoxic effector cells as measured by /sup 51/Cr release from labeled target cells. The RPMI 8226-sensitized lymphocytes were cytotoxic for myeloma cells (RPMI 8226 and K-737) and for lymphoblastoid cells (RAMM) but not for cells from human lung tumor lines (A549, A427, MB9812), a breast carcinoma line (ALAB), a normal diploid fibroblast line (HSBP), or normal lymphocytes.

  2. Low level dose induced chromosome aberrations in human blood lymphocytes

    Pohl-Rueling, J.

    1992-01-01

    Unstable structural aberrations in chromosomes of human blood lymphocytes cannot be used as biological dosemeters in the low dose range, when extrapolating from high doses using a linear dose response, as required by the original formula of the dual radiation action theory. A survey is given of experimental dose-response curves of chromosome aberrations, obtained in investigations not only by this institute, in cooperation with many other laboratories, but also by various authors in different areas of the world. The results are not compatible with the predicted linear dose relationships at in vivo dose ranges up to 30 mGy.y -1 . The aberration frequencies rise sharply with dose within the normal environmental exposure up to about twice that level. At higher doses, aberration frequencies increase less rapidly and reach a plateau. Some in vitro experiments of various authors with higher doses of low LET radiations, up to about 400 mGy have found dose responses with steps. (author)

  3. MAJOR AND LYMPHOCYTE POPULATIONS OF HUMAN PERIPHERAL BLOOD LYMPHOCYTES AND THEIR REFERENCE VALUES, AS ASSAYED BY MULTI-COLOUR CYTOMETRY

    S. V. Khaidukov

    2009-01-01

    Full Text Available Abstract. Determination of lymphocyte subpopulations and their phenotypes is an important diagnostic feature, in order to elucidate some disturbances connected with immune system functioning. However, insufficient data are obtained when analyzing only major populations of peripheral lymphocytes. In order to perform clinical diagnostics, the data about minor lymphocytic populations and activated cellular pools seem to be more pertinent.Studies of peripheral blood cell subpopulations of healthy donors performed in different Russian regions allowed to assess quantitative distribution intervals for both major and minor immune cell subpopulations in humans. The results obtained, as compared with data from literature, provide an evidence for similar reference intervals for main immune cell subpopulations in healthy donors, independent on their habitation area.Present work has resulted into development of algorithms for cytometric studies and generation of certain panels of monoclonal antibodies enabling evaluation of all main lymphocyte subpopulations, as well as their minor subsets participating in emerging immune response. The distribution intervals have been estimated for such minor subpopulations, as B1- and B2-lymphocytes, memory B-cells, γδ- and αβT-cells, regulatory and naїve T-cells, cytotoxic and secretory NK-cell polupations.The results of present study, while been performed with peripheral blood of healthy donors, may provide a basis of reference values when studying subpopulation profile of immune cells.

  4. Effects of Iron Overload on the Activity of Na,K-ATPase and Lipid Profile of the Human Erythrocyte Membrane.

    Leilismara Sousa

    Full Text Available Iron is an essential chemical element for human life. However, in some pathological conditions, such as hereditary hemochromatosis type 1 (HH1, iron overload induces the production of reactive oxygen species that may lead to lipid peroxidation and a change in the plasma-membrane lipid profile. In this study, we investigated whether iron overload interferes with the Na,K-ATPase activity of the plasma membrane by studying erythrocytes that were obtained from the whole blood of patients suffering from iron overload. Additionally, we treated erythrocytes of normal subjects with 0.8 mM H2O2 and 1 μM FeCl3 for 24 h. We then analyzed the lipid profile, lipid peroxidation and Na,K-ATPase activity of plasma membranes derived from these cells. Iron overload was more frequent in men (87.5% than in women and was associated with an increase (446% in lipid peroxidation, as indicated by the amount of the thiobarbituric acid reactive substances (TBARS and an increase (327% in the Na,K-ATPase activity in the plasma membrane of erythrocytes. Erythrocytes treated with 1 μM FeCl3 for 24 h showed an increase (132% in the Na,K-ATPase activity but no change in the TBARS levels. Iron treatment also decreased the cholesterol and phospholipid content of the erythrocyte membranes and similar decreases were observed in iron overload patients. In contrast, erythrocytes treated with 0.8 mM H2O2 for 24 h showed no change in the measured parameters. These results indicate that erythrocytes from patients with iron overload exhibit higher Na,K-ATPase activity compared with normal subjects and that this effect is specifically associated with altered iron levels.

  5. Growth of human T lymphocyte colonies from whole blood: culture requirements and applications

    Knox, S.J.; Wilson, F.D.; Greenberg, B.R.; Shifrine, M.

    1982-01-01

    Growth of human lymphocyte colonies from whole blood following stimulation with PHA, Con A, or PPD is described. Individual colony cells were identified as T lymphocytes on the basis of surface marker and enzyme cytochemical characterizations. Colony formation increased as a power function over a wide range of cell concentrations above a critical minimal concentration. The whole blood culture system eliminates possible selective effects of lymphocyte colony techniques utilizing gradient-enriched lymphocyte fractions and more closely approximates the in vivo milieu. The whole blood colony method is more sensitive for the detection of low-level radiation effects on lymphocytes than widely used tests that measure 3 H-thymidine incorporation. In preliminary studies, researchers used the whole blood method to determine the relative radiosensitivity of lymphocytes from humans with various hematopoietic disorders, and observed abnormalities in mitogen responsiveness and colony formation in some of the patient groups. This method has wide application for studies in cellular and clinical immunology

  6. Influence of high energy electron irradiation and gamma irradiation on the osmotic resistance of human erythrocyte membranes

    Catana, D.; Hategan, Alina; Moraru, Rodica; Popescu, Alina; Morariu, V. V.

    1998-01-01

    The effects of 5 MeV electrons and of gamma irradiation at 0 deg. C on the osmotic fragility of human erythrocyte membranes are presented. Both electron and gamma radiation in the range 0-400 Gy induced no hemolysis indicating that the membrane modifications due to radiation interaction do not reach a critical point as to cause swelling of the cells and subsequent lysis. The osmotic stress experiments performed after irradiation showed that the gamma irradiated erythrocytes exhibited an almost similar sigmoidal behavior for all irradiation doses, whereas the electron irradiated samples showed a much larger increase in hemolysis degree and, in the case of a given electron dose (100 Gy), the hemolysis was found much smaller than for the control sample (a similar behavior of the erythrocytes was found in the case of microwave irradiation at temperatures under 0 deg. C). Our experimental data suggest that electron radiation and gamma radiation have different impacts on the erythrocyte membrane fluidity, involving, probably, the different rate of energy deposition in the samples and the direct interaction of electrons with the erythrocyte membranes. (authors)

  7. Microcalorimetric measurements of heat production in human erythrocytes. IV. Comparison between different calorimetric techniques, suspension media, and preparation methods.

    Monti, M; Wadsö, I

    1976-10-01

    Heat production in human erythrocytes from healthy subjects has been measured under different experimental conditions. Simultaneous measurements were made on the same samples using different types of microcalorimeters: a static ampoule calorimeter, an air perfusion calorimeter, and a flow calorimeter. Obtained heat effect values for specified standard conditions, P degrees, were within uncertainty limits the same for the different calorimeters. Cells were suspended either in autologous plasma or in a phosphate buffer. P degrees values for buffer suspensions were significantly higher than those for plasma suspensions. Erythrocyte samples prepared by the column adsorption technique gave higher P degrees values than those obtained by a conventional centrifugation procedure.

  8. Effect of some radiosensitising drugs on human erythrocyte membrane - - spin label study

    Mishra, K P [Bhabha Atomic Research Centre, Bombay (India). Biology and Agriculture Div.

    1982-02-01

    Electron spin resonance and spin label techniques have been employed to study the effects of local anaesthetic drugs, procaine and tetracaine, on human erythrocyte membrane. Both the drugs altered the protein and lipid arrangements in the membrane and these changes were reversible. Procaine had greater effect on the labels attached to proteins while tetracaine fluidized interior of lipid bilayer to a greater extent. The differential effects of these drugs on the protein and lipid labels have been interpreted in terms of their relative penetrability in the membrane. Present results have explained that radiation induced enhanced killing of cells in the presence of these drugs might be due to the alterations in membrane, particularly proteins both structural and enzymatic. In addition, these results indicate a possible relationship between drug-induced structural changes in membrane and their anaesthetic potency.

  9. Membrane-bound 2,3-diphosphoglycerate phosphatase of human erythrocytes.

    Schröter, W; Neuvians, M

    1970-12-01

    Gradual osmotic hemolysis of human erythrocytes reduces the cell content of whole protein, hemoglobin, 2,3-diphosphoglycerate and triosephosphate isomerase extensively, but not that of membrane protein and 2,3-diphosphoglycerate phosphatase. After the refilling of the ghosts with 2,3-diphosphoglycerate and reconstitution of the membrane, the 2,3-diphosphoglycerate phosphatase activity equals that of intact red cells. The membrane-bound 2,3-diphosphoglycerate phosphatase can be activated by sodium hyposulfite. The enzyme system of ghosts seems to differ from that of intact red cells with regard to the optima of pH and temperature. It remains to be elucidated if the membrane binding of the 2,3-diphosphoglycerate phosphatase is related to the transfer of inorganic phosphate across the red cell membrane.

  10. Cytogenetic analysis of the combined action of pesticides and radiation on human lymphocytes

    Ryabchenko, N.I.; Fesenko, Eh.V.; Antoshchina, M.M.

    1995-01-01

    The efficiency of the combined action of pesticides and irradiation at the G 0 stage was studied in cultured human lymphocytes. Carbophos (malathion) increased the yield of chromosome and chromatid fragments in irradiated lymphocytes. Herbicide 2,4-D (dichlorophenoxyacetic acid) raised lymphocyte radiosensitivity by increasing the yield of chromosome type aberrations, the radiosensitizing effect of the herbicide decreased as its concentration increased. 4 refs

  11. Study of kinetics of 2,3-diphosphoglycerate degradation by 31P-NMR technique in depleted human erythrocytes

    Ataullakhanov, F.I.; Vitvitskii, V.M.; Dubinskaya, E.I.; Dubinskii, V.Z.

    1986-01-01

    The kinetics of 2,3-diphosphoglycerate degradation in depleted human erythrocytes was studied by the high-resolution 31 P-NMR technique. A plateau was found on the kinetic curve in the first 1.5-2 h after the beginning of depletion. The mechanisms that may be responsible for the existence of such a plateau are discussed

  12. Induction of chromosomal aberrations in human lymphocytes by fission neutrons

    Silva, Marcia Augusta da; Coelho, Paulo Rogerio Pinto; Bartolini, Paolo; Okazaki, Kayo

    2009-01-01

    Chromosome aberrations induced by sparsely ionizing radiation (low-LET) are well known and cytogenetic analyses of irradiated human lymphocytes have been widely applied to biological dosimetry. However, much less is known about chromosome aberrations induced by densely ionizing radiation (high LET), such as that of alpha particles or neutrons. Such particles induce DNA strand breaks, as well as chromosome breakage and rearrangements of high complexity. This damage is more localized and less efficiently repaired than after X- or γ-ray irradiation. This preferential production of complex aberrations by densely ionizing radiation is related to the unique energy deposition patterns, which produces highly localized multiple DNA damage at the chromosomal level. A better knowledge of the interactions between different types of radiation and cellular DNA is of importance, not only from the radiobiological viewpoint but also for dosimetric and therapeutic purposes. The objective of the present study was to analyse the cytogenetic effects of fission neutrons on peripheral blood lymphocytes in order to evaluate structural and numerical aberrations and number of cells in the different mitotic cycles. So, blood samples from five healthy donors, 22-25 years old, of both sexes, were irradiated in the Research Reactor IEA-R1 of our Institute (IPEN/CNEN-SP) with thermal and fast neutrons at doses of 0.2; 0.3; 0.5 and 1.0 Gy. The γ contribution to the total absorbed dose was about 30%. These doses were monitored by thermoluminescent dosemeters: LiF-600 (for neutrons) and LiF-700 (for γ-rays). The data concerning structural aberrations were evaluated with regard to three parameters: percentage of cells with aberrations, number of aberrations/cell and number of dicentric/cell. The cytogenetic results showed an increase in the three parameters after irradiation with neutrons, as a function of radiation dose. Apparently, there was no influence of neutrons on the kinetics of cellular

  13. COMPARATIVE GENOTOXIC RESPONSES TO ARSENITE IN GUINEA PIG, MOUSE, RAT AND HUMAN LYMPHOCYTES

    Comparative genotoxic responses to arsenite in guinea pig, mouse, rat and human lymphocytes.Inorganic arsenic is a known human carcinogen causing skin, lung, and bladder cancer following chronic exposures. Yet, long-term laboratory animal carcinogenicity studies have ...

  14. Demonstration of specific binding sites for 3H-RRR-alpha-tocopherol on human erythrocytes

    Kitabchi, A.E.; Wimalasena, J.

    1982-01-01

    Previous work from our laboratory demonstrated specific binding sites for 3 H-RRR-alpha-tocopherol ( 3 H-d alpha T) in membranes of rat adrenal cells. As tocopherol deficiency is associated with increased susceptibility of red blood cells to hemolysis, we investigated tocopherol binding sites in human RBCs. Erythrocytes were found to have specific binding sites for 3 H-d alpha T that exhibited saturability and time and cell-concentration dependence as well as reversibility of binding. Kinetic studies of binding demonstrated two binding sites--one with high affinity (Ka of 2.6 x 10(7) M-1), low capacity (7,600 sites per cell) and the other with low affinity (1.2 x 10(6) M-1), high capacity (150,000 sites per cell). In order to localize the binding sites further, RBCs were fractionated and greater than 90% of the tocopherol binding was located in the membranes. Similar to the findings in intact RBCs, the membranes exhibited two binding sites with a respective Ka of 3.3 x 10(7) M-1 and 1.5 x 10(6) M-1. Specificity data for binding demonstrated 10% binding for RRR-gamma-tocopherol, but not other tocopherol analog exhibited competition for 3 H-d alpha T binding sites. Instability data suggested a protein nature for these binding sites. Preliminary studies on Triton X-100 solubilized fractions resolved the binding sites to a major component with an Mr of 65,000 and a minor component with an Mr of 125,000. We conclude that human erythrocyte membranes contain specific binding sites for RRR-alpha-tocopherol. These sites may be of physiologic significance in the function of tocopherol on the red blood cell membrane

  15. Hydroxychloroquine binding to cytoplasmic domain of Band 3 in human erythrocytes: Novel mechanistic insights into drug structure, efficacy and toxicity.

    Nakagawa, Mizuki; Sugawara, Kotomi; Goto, Tatsufumi; Wakui, Hideki; Nunomura, Wataru

    2016-05-13

    Hydroxychloroquine (HCQ) is a widely used drug in the treatment of autoimmune diseases, such as arthritis and systemic lupus erythematosus. It has also been prescribed for the treatment of malaria owing to its lower toxicity compared to its closely related compound chloroquine (CQ). However, the mechanisms of action of HCQ in erythrocytes (which bind preferentially this drug) have not been documented and the reasons underlying the lower side effects of HCQ compared to CQ remain unclear. Here we show that, although the activity of erythrocyte lactate dehydrogenase (LDH), but not GAPDH, was inhibited by both HCQ and CQ in vitro, LDH activity in erythrocytes incubated with 20 mM HCQ was not significantly reduced within 5 h in contrast to CQ did. Using HCQ coupled Sepharose chromatography (HCQ-Sepharose), we identified Band 3, spectrin, ankyrin, protein 4.1R and protein 4.2 as HCQ binding proteins in human erythrocyte plasma membrane. Recombinant cytoplasmic N-terminal 43 kDa domain of Band 3 bound to HCQ-Sepharose and was eluted with 40 mM (but not 20 mM) HCQ. Band 3 transport activity was reduced by only 23% in the presence of 20 mM HCQ. Taken together, these data demonstrate that HCQ binds to the cytoplasmic N-terminal domain of Band 3 in human erythrocytes but does not inhibit dramatically its transport activity. We hypothesize that the trapping of HCQ on Band 3 contributes to the lower side effects of the drug on energy production in erythrocytes. Copyright © 2016 Elsevier Inc. All rights reserved.

  16. A technique for separation of canine lymphocytes and their use in the lymphocytotoxic, blastogenic, and rosette assys.

    Whitacre, C C; Lang, R W

    1975-01-01

    When the techniques established for preparing lymphocytes from human blood were applied to canine blood, the resulting preparations were contaminated with significant numbers of other blood cells. A three-step technique is described here for the separation of canine lymphocytes from blood which eliminates most granulocytes, platelets, and erythrocytes. Defibrinated blood is incubated with iron particles to allow phagocytosis by granulocytes. When mixed with Plasmagel, erythrocytes and iron-containing granulocytes sediment rapidly, leaving a lymphocyte-rich supernate plasma which is recovered and banded by centrifugation on a Ficoll-Hypaque gradient. Any erythrocytes remaining in the lymphocyte suspension aspirated from the gradient are eliminated by hypotonic lysis and centrifugation. The resulting preparation, representing 30 per cent recovery of the circulating lymphocytes, contained 85 to 94 per cent lymphocytes with a cell viability of 99 per cent. The functional capacity of the lymphocyte preparation was tested in three assays: 1) lymphoblastic transformation using phytohemagglutinin and pokeweed mitogen, 2) E rosette formation with human erythrocytes showed a mean 5 per cent rosette forming lymphocytes, 3) antibody-mediated lymphocytotoxicity using a canine anti-lymphocyte serum showed titers reproducible within one tube dilution.

  17. Active site of tripeptidyl peptidase II from human erythrocytes is of the subtilisin type

    Tomkinson, B.; Wernstedt, C.; Hellman, U.; Zetterqvist, Oe.

    1987-11-01

    The present report presents evidence that the amino acid sequence around the serine of the active site of human tripeptidyl peptidase II is of the subtilisin type. The enzyme from human erythrocytes was covalently labeled at its active site with (/sup 3/H)diisopropyl fluorophosphate, and the protein was subsequently reduced, alkylated, and digested with trypsin. The labeled tryptic peptides were purified by gel filtration and repeated reversed-phase HPLC, and their amino-terminal sequences were determined. Residue 9 contained the radioactive label and was, therefore, considered to be the active serine residue. The primary structure of the part of the active site (residues 1-10) containing this residue was concluded to be Xaa-Thr-Gln-Leu-Met-Asx-Gly-Thr-Ser-Met. This amino acid sequence is homologous to the sequence surrounding the active serine of the microbial peptidases subtilisin and thermitase. These data demonstrate that human tripeptidyl peptidase II represents a potentially distinct class of human peptidases and raise the question of an evolutionary relationship between the active site of a mammalian peptidase and that of the subtilisin family of serine peptidases.

  18. Human mixed lymphocyte cultures. Evaluation of microculture technique utilizing the multiple automated sample harvester (MASH)

    Thurman, G. B.; Strong, D. M.; Ahmed, A.; Green, S. S.; Sell, K. W.; Hartzman, R. J.; Bach, F. H.

    1973-01-01

    Use of lymphocyte cultures for in vitro studies such as pretransplant histocompatibility testing has established the need for standardization of this technique. A microculture technique has been developed that has facilitated the culturing of lymphocytes and increased the quantity of cultures feasible, while lowering the variation between replicate samples. Cultures were prepared for determination of tritiated thymidine incorporation using a Multiple Automated Sample Harvester (MASH). Using this system, the parameters that influence the in vitro responsiveness of human lymphocytes to allogeneic lymphocytes have been investigated. PMID:4271568

  19. Effect of thapsigargin on cytoplasmic Ca2+ and proliferation of human lymphocytes in relation to AIDS

    Scharff, O; Foder, B; Thastrup, Ole

    1988-01-01

    The tumor-promoting sesquiterpene lactone, thapsigargin, induced a dose-dependent increase of the cytoplasmic Ca2+ concentration ([ Ca2+]i) in human lymphocytes from a resting level between 100 and 150 nM up to about 1 microM. Half-maximum response was found at about 1 nM of thapsigargin, full...... of the lymphocytes, which was much higher than that caused by the PHA treatment, even in AIDS lymphocytes. Moreover, the thapsigargin/PMA treatment stimulated the expression of the IL-2 receptors on both normal and AIDS lymphocytes, similar to the effect of PHA. It is concluded that thapsigargin exerts its effects...

  20. Effects of flaxseed oil on anti-oxidative system and membrane deformation of human peripheral blood erythrocytes in high glucose level.

    Yang, Wei; Fu, Juan; Yu, Miao; Huang, Qingde; Wang, Di; Xu, Jiqu; Deng, Qianchun; Yao, Ping; Huang, Fenghong; Liu, Liegang

    2012-07-08

    The erythrocyte membrane lesion is a serious diabetic complication. A number of studies suggested that n-3 fatty acid could reduce lipid peroxidation and elevate α- or γ-tocopherol contents in membrane of erythrocytes. However, evidence regarding the protective effects of flaxseed oil, a natural product rich in n-3 fatty acid, on lipid peroxidation, antioxidative capacity and membrane deformation of erythrocytes exposed to high glucose is limited. Human peripheral blood erythrocytes were isolated and treated with 50 mM glucose to mimic hyperglycemia in the absence or presence of three different doses of flaxseed oil (50, 100 or 200 μM) in the culture medium for 24 h. The malondialdehyde (MDA) and L-glutathione (GSH) were measured by HPLC and LC/MS respectively. The phospholipids symmetry and membrane fatty acid composition of human erythrocytes were detected by flow cytometry and gas chromatograph (GC). The morphology of human erythrocyte was illuminated by ultra scanning electron microscopy. Flaxseed oil attenuated hyperglycemia-induced increase of MDA and decrease of GSH in human erythrocytes. Human erythrocytes treated with flaxseed oil contained higher C22:5 and C22:6 than those in the 50 mM glucose control group, indicating that flaxseed oil could reduce lipid asymmetric distribution and membrane perturbation. The ultra scanning electron microscopy and flow cytometer have also indicated that flaxseed oil could protect the membrane of human erythrocytes from deformation at high glucose level. The flaxseed oil supplementation may prevent lipid peroxidation and membrane dysfunction of human erythrocytes in hyperglycemia.

  1. Reactivity of eleven anti-human leucocyte monoclonal antibodies with lymphocytes from several domestic animals

    Aasted, Bent; Blixenkrone-Møller, Merete; Larsen, Else Bang

    1988-01-01

    Nine commercially available monoclonal antibodies and two monoclonal antibodies from The American Type Culture Collection, raised against various human leucocyte surface antigens, were tested on lymphocytes from cow, sheep, goat, swine, horse, cat, dog, mink, and rabbit as well as man. Four...... antibodies bound to lymphocytes from some of the animals. These were the antibodies against CD8 and CD4 antigen, the antibody to C3b-receptor, and the antibody to the HLA-DR antigen. The CD8 antigen-reactive antibody reacted with lymphocytes from mink, cat, dog, and sheep, while the CD4 antigen......-reactive antibody reacted with lymphocytes from mink. The anti-C3b-R antibody reacted with lymphocytes from horse, swine, dog, and cat, and the anti-HLA-DR reacted with lymphocytes from cow, goat, sheep, horse, dog, cat, and mink....

  2. Differentiation of human B lymphocyte subpopulations induced by an alloreactive helper T-cell clone

    Anderson, S.J.; Hummell, D.S.; Lawton, A.R.

    1988-01-01

    We have used cloned alloreactive helper T cells to determine if direct T cell-B cell interaction can induce differentiation of human peripheral blood B cells which do not respond to pokeweed mitogen (PWM). T-cell clone 2F8 was derived from a one-way mixed lymphocyte reaction. 2F8 cells are T3+T4+T8-IL-2R+ and proliferate in response to irradiated stimulator cells, but not autologous cells, in the absence of exogenous interleukin-2. 2F8 cells provide allospecific help for polyclonal proliferation and differentiation of B cells in the absence of any other stimulus. The magnitude of this response is comparable to that of the response of the same B cells to PWM and fresh autologous T cells. 2F8 cells could also provide nonspecific help for unrelated donor B cells in the presence of PWM, with no requirement for costimulation by irradiated stimulator cells. Allospecific stimulation of B cells was completely inhibited by antibodies to class II major histocompatibility complex (MHC) framework determinants and was abrogated by 1000-rad irradiation. Cloned 2F8 T cells stimulated differentiation of both small, high-density B cells and larger B cells, generating up to 30% plasma cells with either fraction. B cells forming rosettes with mouse erythrocytes were also induced to differentiate by the helper T cell clone. As found previously, neither small, high-density B cells nor mouse rosette+ B cells responded well to PWM. Direct interaction with allospecific T cells induces differentiation of a broader spectrum of B cells than soluble growth and differentiation factors in conjunction with polyclonal activators such as PWM and protein A containing staphylococci

  3. A rapid radioassay for human IgG produced in lymphocyte in vitro culture systems

    Weightman, D.R.; Shale, D.J.; Tomlinson, W.R.

    1981-01-01

    Protein A bearing Staphylococcus aureus was used to develop a solid-phase radioassay for IgG immunoglobulins. The assay was specifically optimised for use in vitro human lymphocyte culture work. Compared with a solid-phase radioimmunoassay for IgG produced in lymphocyte culture, this assay had a similar performance profile and the advantages of rapidity and technical ease. (Auth.)

  4. Labeling with indium-111 has detrimental effects on human lymphocytes: concise communication

    ten Berge, R. J.; Natarajan, A. T.; Hardeman, M. R.; van Royen, E. A.; Schellekens, P. T.

    1983-01-01

    When lymphocytes from human peripheral blood were labeled with In-111 oxinate, several of their properties appeared to be affected. The spontaneous release of the radionuclide was found to be relatively high. Labeled lymphocytes showed a decreased proliferative capacity, dependent on the dose of the

  5. Operation of the Ca-dependent K(Rb)-transport in human lymphocytes

    Szasz, I.; Sarkadi, B.; Gardos, G. (Orszagos Haematologiai es Vertranszfuzios Intezet, Budapest (Hungary))

    1982-01-01

    The transport pathways of the plasma membrane of human lymphocytes were studied based on /sup 86/Rb and /sup 45/Ca fluxes. Net Ca-uptake increases K(Rb)-permeability (Gardos-effect) and the membrane potential increases due to the subsequent K-efflux, enabling further Ca-uptake. The possible role of the above effects during lymphocyte stimulation is discussed.

  6. Carotenoids located in human lymphocyte subpopulations and Natural Killer cells by Raman microspectroscopy

    Puppels, G.J.; Puppels, G.J.; Garritsen, H.S.P.; Garritsen, H.S.P.; Kummer, J.A.; Greve, Jan

    1993-01-01

    The presence and subcellular location of carotenoids in human lymphocyte sub-populations (CD4+, CD8+, T-cell receptor-γδ+, and CD19+ ) and natural killer cells (CD16+ ) were studied by means of Raman microspectroscopy. In CD4+ lymphocytes a high concentration (10-3M) of carotenoids was found in the

  7. PHA-induced cytotoxicity of human lymphocytes against adherent hela-cells

    Huges-Law, G.; de Gast, G. C.; The, T. Hauw

    The conditions for a phytohaemagglutinin(PHA)-induced cytotoxicity test of human peripheral blood lymphocytes were investigated. [3H]thymidine prelabelled HeLa cells were used as target cells. Stimulation with 10 μl PHA/ml during 24 h gave the best measure of lymphocyte cytotoxic capacity.

  8. Effects of ketotifen on human lymphocytes in vitro and in vivo

    Petrasch, S.; van Tits, L. J.; Motulsky, H. J.; Brodde, O. E.; Michel, M. C.

    1993-01-01

    The effects of the antiasthmatic drug ketotifen (CAS 34580-13-7) on human mononuclear leukocytes were studied in vitro and in vivo. In vitro ketotifen concentration-dependently inhibited mitogen-stimulated lymphocyte proliferation. High ketotifen concentrations also inhibited T-lymphocyte mitogen-

  9. Natural HIV-1 NEF accelerates virus replication in primary human lymphocytes

    de Ronde, A.; Klaver, B.; Keulen, W.; Smit, L.; Goudsmit, J.

    1992-01-01

    HIV-1 NEF genes were isolated directly from peripheral blood lymphocyte DNA of two HIV-1-infected individuals and cloned into an HXB-2-infectious molecular clone. The effect of NEF on virus production in T-cell lines and primary human lymphocytes was studied. Naturally occurring NEF accelerates

  10. Isolation and characterization of cDNA clones for human erythrocyte β-spectrin

    Prchal, J.T.; Morley, B.J.; Yoon, S.H.; Coetzer, T.L.; Palek, J.; Conboy, J.G.; Kan, Y.W.

    1987-01-01

    Spectrin is an important structural component of the membrane skeleton that underlies and supports the erythrocyte plasma membrane. It is composed of nonidentical α (M/sub r/ 240,000) and β (M/sub r/ 220,000) subunits, each of which contains multiple homologous 106-amino acid segments. The authors report here the isolation and characterization of a human erythroid-specific β-spectrin cDNA clone that encodes parts of the β-9 through β-12 repeat segments. This cDNA was used as a hybridization probe to assign the β-spectrin gene to human chromosome 14 and to begin molecular analysis of the gene and its mRNA transcripts. RNA transfer blot analysis showed that the reticulocyte β-spectrin mRNA is 7.8 kilobases in length. Southern blot analysis of genomic DNA revealed the presence of restriction fragment length polymorphisms (RFLPs) within the β-spectrin gene locus. The isolation of human spectrin cDNA probes and the identification of closely linked RFLPs will facilitate analysis of mutant spectrin genes causing congenital hemolytic anemias associated with quantitative and qualitative spectrin abnormalities

  11. Detection of antibodies in human serum using trimellityl-erythrocytes: direct and indirect haemagglutination and haemolysis.

    Turner, E S; Pruzansky, J J; Patterson, R; Zeiss, C R; Roberts, M

    1980-02-01

    Utilizing trimellityl-erythrocytes (TM-E), antibodies were detected in sera of seven workers with trimellitic anhydride (TMA) induced airway syndromes by direct haemagglutination, indirect haemagglutination with anti-human IgG, IgA or IgM or by haemolysis. Detectable levels of antibody were obtained with all three methods. The most sensitive technique was indirect haemagglutination using anti-IgG. When added as an inhibitor, TM-human serum albumin produced a 10- to 800-fold reduction in titres. TM-ovalbumin of similar epitope density was less inhibitory and sodium trimellitate the least inhibitory on a molar basis. All of the assays using haptenized human red cells were also capable of detecting anti-TM antibodies in Rhesus monkeys whose airways had been exposed to TMA. These assays are useful for detecting anti-TM antibodies and may also be adapted to demonstrate antibodies induced against other inhaled haptens in sera of environmentally exposed individuals or in animal models of such exposure.

  12. Assessment of in vitro radiosensitivity of human peripheral blood lymphocytes

    Knox, S.J.; Shifrine, M.; Rosenblatt, L.S.

    1980-01-01

    The proliferative capacity of sensitive lymphocyte progenitor cells, from thirty-one clinically normal adults, was evaluated following in vitro x-irradiation (0-400R). Radiation effects were studied using both whole blood and lymphocyte-enriched mononuclear cell fractions in the lymphocyte stimulation test and colony formation assay with 6 different mitogens and antigens. Radiation dose-response survival curves were determined for the different test groups. The sensitivity of the different assay systems is compared and normative values are presented that may be used for comparison purposes to determine the relative radiosensitivity of atypical individuals and groups of individuals

  13. Bio-field array: a dielectrophoretic electromagnetic toroidal excitation to restore and maintain the golden ratio in human erythrocytes.

    Purnell, Marcy C; Butawan, Matthew B A; Ramsey, Risa D

    2018-06-01

    Erythrocytes must maintain a biconcave discoid shape in order to efficiently deliver oxygen (O 2 ) molecules and to recycle carbon dioxide (CO 2 ) molecules. The erythrocyte is a small toroidal dielectrophoretic (DEP) electromagnetic field (EMF) driven cell that maintains its zeta potential (ζ) with a dielectric constant (ԑ) between a negatively charged plasma membrane surface and the positively charged adjacent Stern layer. Here, we propose that zeta potential is also driven by both ferroelectric influences (chloride ion) and ferromagnetic influences (serum iron driven). The Golden Ratio, a function of Phi φ, offers a geometrical mathematical measure within the distinct and desired curvature of the red blood cell that is governed by this zeta potential and is required for the efficient recycling of CO 2 in our bodies. The Bio-Field Array (BFA) shows potential to both drive/fuel the zeta potential and restore the Golden Ratio in human erythrocytes thereby leading to more efficient recycling of CO 2 . Live Blood Analyses and serum CO 2 levels from twenty human subjects that participated in immersion therapy sessions with the BFA for 2 weeks (six sessions) were analyzed. Live Blood Analyses (LBA) and serum blood analyses performed before and after the BFA immersion therapy sessions in the BFA pilot study participants showed reversal of erythrocyte rheological alterations (per RBC metric; P = 0.00000075), a morphological return to the Golden Ratio and a significant decrease in serum CO 2 (P = 0.017) in these participants. Immersion therapy sessions with the BFA show potential to modulate zeta potential, restore this newly defined Golden Ratio and reduce rheological alterations in human erythrocytes. © 2018 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Physiological Society and the American Physiological Society.

  14. Subpopulation of human helper and suppressor T lymphocytes

    Venkataraman, M.; Levin, R.D.; Westerman, M.P.

    1983-01-01

    Mitogen driven differentiation of normal human mononuclear cells is a well-established model for the study of antibody synthesis in man. In certain rare individuals who are clinically normal, unfractionated mononuclear cells or a mixture of purified B plus T lymphocytes differentiate into immunoglobulin producing cells in response to purified protein derivative of tuberculin (PPD) but not in response to pokeweed mitogen (PWM). To evaluate this observation we have irradiated T cells from such individuals to eliminate naturally occurring suppressor T cell activity and then added the irradiated T cells back to autologous B cells before culture. The B cells then responded to PWM. The original PPD responses of cells from these individuals were now significantly reduced. Although, there was no difference between PWM nonresponders and responders in the number of OKT-8 positive cells, elimination of OKT-8 positive cells in the PWM nonresponders with OKT-8 monoclonal antibody and complement resulted in a significantly increased response to PWM. This study indicates that there are suppressor T cells which specifically inhibit B cell response to PWM without affecting the PPD response. These results also show that the helper T cells involved in the PWM response are radioresistant and those involved in the PPD response are radiosensitive

  15. Molecular cloning of human protein 4.2: A major component of the erythrocyte membrane

    Sung, L.A.; Chien, Shu; Lambert, K.; Chang, Longsheng; Bliss, S.A.; Bouhassira, E.E.; Nagel, R.L.; Schwartz, R.S.; Rybicki, A.C.

    1990-01-01

    Protein 4.2 (P4.2) comprises ∼5% of the protein mass of human erythrocyte (RBC) membranes. Anemia occurs in patients with RBCs deficient in P4.2, suggesting a role for this protein in maintaining RBC stability and integrity. The authors now report the molecular cloning and characterization of human RBC P4.2 cDNAs. By immunoscreening a human reticulocyte cDNA library and by using the polymerase chain reaction, two cDNA sequences of 2.4 and 2.5 kilobases (kb) were obtained. These cDNAs differ only by a 90-base-air insert in the longer isoform located three codons downstream from the putative initiation site. The 2.4- and 2.5-kb cDNAs predict proteins of ∼77 and ∼80 kDa, respectively, and the authenticity was confirmed by sequence identity with 46 amino acids of three cyanogen bromide-cleaved peptides of P4.2. Northern blot analysis detected a major 2.4-kb RNA species in reticulocytes. Isolation of two P4.2 cDNAs implies existence of specific regulation of P4.2 expression in human RBCs. Human RBC P4.2 has significant homology with human factor XIII subunit a and guinea pig liver transglutaminase. Sequence alignment of P4.2 with these two transglutaminases, however, revealed that P4.2 lacks the critical cysteine residue required for the enzymatic crosslinking of substrates

  16. The Genotoxicity of Sodium Arsenite in Human Lymphocyte Culture

    El-Habit Ola, H.M.

    1998-01-01

    Sodium arsenite was tested for its clastogenic effect alone and on isolated lymphocyte culture. The results showed a significant difference in the yield of chromosome aberrations induced with respect to the culture time 48 h. Whole blood culture showed significant increase in gaps and breaks whereas isolated lymphocyte culture showed significant inhibition of cell cycle and 75% of the lymphocytes were in their first cell cycle at 72 hr. Arsenite showed co-mutagenicity with different doses of x-ray delivered immediately or few hours after treatment of the culture with S A. The results suggest that S A is also mutagenic at the dose level used and provide support for the indispensability of whole blood culture for evaluation of the in vivo effect of any suspected mustagen using isolated lymphocytes appear to have problems leading to extensive cell cycle delay

  17. The genotoxicity of sodium arsenite in human lymphocyte culture

    Elhabit, O.H.M.

    1995-01-01

    Sodium arsenite was tested for its clastogenic effect alone and in combination with x-irradiation on whole blood culture and on isolated lymphocyte culture. The results showed a significant difference in the yield of aberrations induced with respect to the culture time 48 hr whole blood culture showed significant increase in gaps and breaks whereas isolated lymphocytes culture showed significant inhibition of cell cycle and 75% of the lymphocytes were in first cell cycle at 72 hr. Arsenite showed co-mutagenicity with different doses of x-ray delivered immediately or few hours after treatment of the culture with SA. The results suggest that SA also is mutagenic at the dose level used and provide support for the indispensability of whole blood culture for evaluation of the in vivo effect any suspected mutagen. Using isolated lymphocytes appear to have problems leading to extensive cell cycle delay

  18. Response of human lymphocytes to low gamma ray doses

    Vega Carrillo, HR; Banuelos Valenzuela, R; Manzanares Acuna, E; Sanchez-Rodriguez, S.H

    2001-01-01

    Radiation and non-radiation workers lymphocytes were exposed to a low strength gamma-ray field to determine heat shock protein expression in function of radiation dose. Protein identification was carried out using mAb raised against Hsp25, Hsp60, Hsp70 and Hsp90; from these, only Hsp70 protein was detected before and after lymphocyte irradiation. In all cases, an increasing trend of relative amounts of Hsp70 in function to irradiation time was observed. After 70.5 mGy gamma-ray dose, radiation worker's lymphocytes expressed more Hsp70 protein, than non-radiation workers' lymphocytes, indicating a larger tolerance to gamma rays (gamma tolerance), due to an adaptation process developed by their labor condition (Au)

  19. The 10 kDa domain of human erythrocyte protein 4.1 binds the Plasmodium falciparum EBA-181 protein

    Coetzer Theresa L

    2006-11-01

    Full Text Available Abstract Background Erythrocyte invasion by Plasmodium falciparum parasites represents a key mechanism during malaria pathogenesis. Erythrocyte binding antigen-181 (EBA-181 is an important invasion protein, which mediates a unique host cell entry pathway. A novel interaction between EBA-181 and human erythrocyte membrane protein 4.1 (4.1R was recently demonstrated using phage display technology. In the current study, recombinant proteins were utilized to define and characterize the precise molecular interaction between the two proteins. Methods 4.1R structural domains (30, 16, 10 and 22 kDa domain and the 4.1R binding region in EBA-181 were synthesized in specific Escherichia coli strains as recombinant proteins and purified using magnetic bead technology. Recombinant proteins were subsequently used in blot-overlay and histidine pull-down assays to determine the binding domain in 4.1R. Results Blot overlay and histidine pull-down experiments revealed specific interaction between the 10 kDa domain of 4.1R and EBA-181. Binding was concentration dependent as well as saturable and was abolished by heat denaturation of 4.1R. Conclusion The interaction of EBA-181 with the highly conserved 10 kDa domain of 4.1R provides new insight into the molecular mechanisms utilized by P. falciparum during erythrocyte entry. The results highlight the potential multifunctional role of malaria invasion proteins, which may contribute to the success of the pathogenic stage of the parasite's life cycle.

  20. NMR studies of human blood cells in health and disease. I. Alterations of the plasma membrane water permeability of erythrocytes

    Katona, Eva; Doaga, I. O.; Radulet, Diana; Caplanusi, A.; Negreanu, Cezarina; Mihele, Denisa

    1999-01-01

    Alterations in pathological cases of the human erythrocyte membrane water permeability were investigated by using a Mn 2+ -doping 1 H nuclear magnetic resonance (NMR) technique. The temperature dependence of the apparent water diffusional exchange through erythrocyte membranes in chronic hepatitis, diabetes, dyslipidemia and essential hypertension was measured and compared to healthy controls. Using moderate manganese concentrations (9-18 mM) and Carr-Purcell-Meiboom-Gill pulse sequences with a large number of refocusing π pulses and short interpulse delay (100 μs) our values of the water exchange times (τ e ) across erythrocyte membranes, obtained within a 10 min time period following the moment of doping, were independent of the actual manganese concentration and the Arrhenius plot for water exchange was linear over the range of 22-42 deg C. A marked increase of the water exchange times values was observed in all studied disease states. In case of chronic hepatitis, diabetes and dyslipidemia the changes observed in transmembrane water exchange time were associated with significant increase in the apparent activation energy of the diffusional water permeability thus, pointing out alterations in the function of the erythrocyte water channel. (author)

  1. NMR studies of human blood cells in health and disease. I. Alterations of the plasma membrane water permeability of erythrocytes

    Katona, Eva; Doaga, I O; Radulet, Diana [Department of Biophysics, Carol Davila University of Medicine and Pharmaceutics, 8 Blvd. Eroilor Sanitari, POB 15-205, RO-76241 Bucharest (Romania); Caplanusi, A [Medical Biochemistry Department, Carol Davila University of Medicine and Pharmaceutics, 8 Blvd. Eroilor Sanitari, POB 15-205, RO-76241 Bucharest (Romania); Negreanu, Cezarina [Division of New Energy Conversion Methods, Institute of Research and Design for Thermoenergetic Equipment, ICPET-CERCETARE, Bucharest (Romania); Mihele, Denisa [Clinical Laboratory Department, Carol Davila University of Medicine and Pharmaceutics, 8 Blvd. Eroilor Sanitari, POB 15-205, RO-76241 Bucharest (Romania)

    1999-07-01

    Alterations in pathological cases of the human erythrocyte membrane water permeability were investigated by using a Mn{sup 2+}-doping {sup 1}H nuclear magnetic resonance (NMR) technique. The temperature dependence of the apparent water diffusional exchange through erythrocyte membranes in chronic hepatitis, diabetes, dyslipidemia and essential hypertension was measured and compared to healthy controls. Using moderate manganese concentrations (9-18 mM) and Carr-Purcell-Meiboom-Gill pulse sequences with a large number of refocusing {pi} pulses and short interpulse delay (100 {mu}s) our values of the water exchange times ({tau}{sub e}) across erythrocyte membranes, obtained within a 10 min time period following the moment of doping, were independent of the actual manganese concentration and the Arrhenius plot for water exchange was linear over the range of 22-42 deg C. A marked increase of the water exchange times values was observed in all studied disease states. In case of chronic hepatitis, diabetes and dyslipidemia the changes observed in transmembrane water exchange time were associated with significant increase in the apparent activation energy of the diffusional water permeability thus, pointing out alterations in the function of the erythrocyte water channel. (author)

  2. SO4= uptake and catalase role in preconditioning after H2O2-induced oxidative stress in human erythrocytes.

    Morabito, Rossana; Remigante, Alessia; Di Pietro, Maria Letizia; Giannetto, Antonino; La Spada, Giuseppina; Marino, Angela

    2017-02-01

    Preconditioning (PC) is an adaptive response to a mild and transient oxidative stress, shown for the first time in myocardial cells and not described in erythrocytes so far. The possible adaptation of human erythrocytes to hydrogen peroxide (H 2 O 2 )-induced oxidative stress has been here verified by monitoring one of band 3 protein functions, i.e., Cl - /HCO 3 - exchange, through rate constant for SO 4 = uptake measurement. With this aim, erythrocytes were exposed to a mild and transient oxidative stress (30 min to either 10 or 100 μM H 2 O 2 ), followed by a stronger oxidant condition (300- or, alternatively, 600-μM H 2 O 2 treatment). SO 4 = uptake was measured by a turbidimetric method, and the possible role of catalase (CAT, significantly contributing to the anti-oxidant system in erythrocytes) in PC response has been verified by measuring the rate of H 2 O 2 degradation. The preventive exposure of erythrocytes to 10 μM H 2 O 2 , and then to 300 μM H 2 O 2 , significantly ameliorated the rate constant for SO 4 = uptake with respect to 300 μM H 2 O 2 alone, showing thus an adaptive response to oxidative stress. Our results show that (i) SO 4 = uptake measurement is a suitable model to monitor the effects of a mild and transient oxidative stress in human erythrocytes, (ii) band 3 protein anion exchange capability is retained after 10 μM H 2 O 2 treatment, (iii) PC response induced by the 10 μM H 2 O 2 pretreatment is clearly detected, and (iv) PC response, elicited by low-concentrated H 2 O 2 , is mediated by CAT enzyme and does not involve band 3 protein tyrosine phosphorylation pathways. Erythrocyte adaptation to a short-term oxidative stress may serve as a basis for future studies about the impact of more prolonged oxidative events, often associated to aging, drug consumption, chronic alcoholism, hyperglycemia, or neurodegenerative diseases.

  3. 31P-NMR measurements of ATP, ADP, 2,3-diphosphoglycerate and Mg2+ in human erythrocytes.

    Petersen, A; Kristensen, S R; Jacobsen, J P; Hørder, M

    1990-08-17

    Absolute 31P-NMR measurements of ATP, ADP and 2,3-diphosphoglycerate (2,3-DPG) in oxygenated and partly deoxygenated human erythrocytes, compared to measurements by standard assays after acid extraction, show that ATP is only 65% NMR visible, ADP measured by NMR is unexpectedly 400% higher than the enzymatic measurement and 2,3-DPG is fully NMR visible, regardless of the degree of oxygenation. These results show that binding to hemoglobin is unlikely to cause the decreased visibility of ATP in human erythrocytes as deoxyhemoglobin binds the phosphorylated metabolites more tightly than oxyhemoglobin. The high ADP visibility is unexplained. The levels of free Mg2+ [( Mg2+]free) in human erythrocytes are 225 mumol/l at an oxygen saturation of 98.6% and instead of the expected increase, the level decreased to 196 mumol/l at an oxygen saturation of 38.1% based on the separation between the alpha- and beta-ATP peaks. [Mg2+]free in the erythrocytes decreased to 104 mumol/l at a high 2,3-DPG concentration of 25.4 mmol/l red blood cells (RBC) and a normal ATP concentration of 2.05 mmol/l RBC. By increasing the ATP concentration to 3.57 mmol/l RBC, and with a high 2,3-DPG concentration of 24.7 mmol/l RBC, the 31P-NMR measured [Mg2+]free decreased to 61 mumol/l. These results indicate, that the 31P-NMR determined [Mg2+]free in human erythrocytes, based solely on the separation of the alpha- and beta-ATP peaks, does not give a true measure of intracellular free Mg2+ changes with different oxygen saturation levels. Furthermore the measurement is influenced by the concentration of the Mg2+ binding metabolites ATP and 2,3-DPG. Failure to take these factors into account when interpreting 31P-NMR data from human erythrocytes may explain some discrepancies in the literature regarding [Mg2+]free.

  4. microRNA expression profiles in human peripheral blood lymphocytes cultured in modeled microgravity

    National Aeronautics and Space Administration — In the present study we analyzed miRNA and mRNA expression profiles in human peripheral blood lymphocytes (PBLs) incubated in microgravity condition simulated by a...

  5. Gene expression profiling of human peripheral blood lymphocytes cultured in modeled microgravity

    National Aeronautics and Space Administration — In the present study we analyzed miRNA and mRNA expression profiles in human peripheral blood lymphocytes (PBLs) incubated in microgravity condition simulated by a...

  6. Analysis of cytotoxic effects of chlorhexidine gluconate as antiseptic agent on human blood lymphocytes.

    Salimi, Ahmad; Alami, Bahare; Pourahmad, Jalal

    2017-08-01

    The aim of this study was to assess the cytotoxicity of chlorhexidine gluconate (CHG) on human blood lymphocytes as a useful ex vivo model for accelerated human toxicity studies. Using biochemical and flow cytometry assessments, we demonstrated that addition of CHG at 1 μM concentration to human blood lymphocytes induced cytotoxicity following 6 h. The CHG-induced cytotoxicity on human blood lymphocytes was associated with intracellular reactive oxygen species generation, mitochondrial membrane potential collapse, lysosomal membrane injury, lipid peroxidation, and depletion of glutathione. According to our results, CHG triggers oxidative stress and organelles damages in lymphocytes which are important cells in defense against foreign agents. Finally our findings suggest that using of antioxidants and mitochondrial/lysosomal protective agents could be of benefit for the people in the exposure with CHG. © 2017 Wiley Periodicals, Inc.

  7. Response of human and rabbit lymphocytes to low doses of X-rays

    Fabry, L.

    1982-01-01

    The response of human and rabbit lymphocytes to low doses of X-rays was studied by the yields of dicentrics in first division metaphases. For both species, the dose-response curve was best fitted to the linear-quadratic model with a linear component predominating up to 67 and 42 rad respectively for man and rabbit. A calibration curve (5-400 rad) was obtained by combining the present results on man with previous data at higher doses. On the other hand, it appears that, at low doses, the radiosentivity of human lymphocytes is significantly higher than that of rabbit lymphocytes [fr

  8. DNA damage in human lymphocytes due to synergistic interaction between ionizing radiation and pesticide

    Kim, J. K.; Lee, K. H.; Lee, B. H.; Chun, K. J.

    2001-01-01

    Biological risks may arise from the possibility of the synergistic interaction between harmful factors such as ionizing radiation and pesticide. The effect of pesticide on radiation-induced DNA damage in human in human blood lymphocytes was evaluated by the single cell gel electrophoresis (SCGE) assay. The lymphocytes, with or without pretreatment of the pesticide, were exposed to 2.0 Gy of gamma ray. Significantly increased tail moment, which was a marker of DNA strand breaks in SCGE assay, showed an excellent dose-response relationship. The present study confirms that the pesticide has the cytotoxic effect on lymphocytes and that it interacts synergistically with ionizing radiationon DNA damage, as well

  9. Cytogenetic adaptive response induced by pre-exposure in human lymphocytes and marrow cells of mice

    Zhang Lianzhen; Deng Zhicheng

    1993-01-01

    The cytogenetic adaptive response induced by pre-exposure in human lymphocytes and marrow cells of mice were studied. The results of this study showed that human lymphocytes in vitro and mouse marrow cells in vivo can become adapted to low-level irradiation from 3 H-TdR or exposure to a low dose of X-or γ-irradiation, so that they become less sensitive to the chromosomal damage effects of subsequent exposures. (4 tabs.)

  10. Phage display used for gene cloning of human recombinant antibody against the erythrocyte surface antigen, rhesus D

    Dziegiel, M; Nielsen, L K; Andersen, P S

    1995-01-01

    A novel phage display system has been developed for PCR amplification and cloning of the Fab fragments of human immunoglobulin genes. Using this system, we have cloned an antibody from a mouse-human hybridoma cell line directed against the erythrocyte antigen rhesus D. Intact erythrocytes were used...... for absorption of the Fab phages. Soluble Fab fragments produced from the cloned material showed identical performance to the parental antibody in agglutination assays. Gel filtration confirmed that the Fab fragment consists of a kappa-Fd heterodimer. The successful use of intact cells for selection of specific...... Fab phages demonstrates that it is possible to by-pass purification of the antigen of interest. Comparison with published germline sequences demonstrated that the immunoglobulin coding regions had the highest homology to the VH 1.9III and V kappa Hum kappa v325 germline genes, respectively....

  11. Characterization of human placental glycosaminoglycans and regional binding to VAR2CSA in malaria infected erythrocytes

    Beaudet, Julie M; Mansur, Leandra; Joo, Eun Ji

    2014-01-01

    expressing VAR2CSA on the erythrocyte surface. This protein adheres to a low-sulfated chondroitin sulfate-A found in placental tissue causing great harm to both mother and developing fetus. In rare cases, the localization of infected erythrocytes to the placenta can even result in the vertical transmission...... placental tissue accessible to parasites in the bloodstream, suggesting it is the primary receptor for parasite infected red blood cells....

  12. Aspirin effects on lymphocyte cyclic AMP levels in normal human subjects.

    Snider, D E; Parker, C W

    1976-01-01

    In purified lymphocytes from the peripheral blood of healthy human subjects who had ingested therapeutic doses of aspirin, there was a significant decrease in resting cyclic AMP levels as well as a partial inhibition of the rise in cyclic AMP with isoproterenol or prostaglandin E1. These changes were seen as early as 30 min after aspirin ingestion and did not appear to result from aspirin effects on lymphocyte recovery, purity, viability, or relative number of thymus- or bone marrow-derived lymphocytes. In contrast, the direct addition of aspirin to suspensions of purified peripheral lymphocytes did not significantly alter their cyclic AMP levels. However, an effect of aspirin could be obtained in vitro if aspirin was added to unprocessed whole blood during the dextran sedimentation phase of the cell purification. Thus the effect of aspirin on lymphocyte cyclic AMP metabolism, may be indirect, through other cells present in the peripheral blood. PMID:182720

  13. The first case of a complete deficiency of diphosphoglycerate mutase in human erythrocytes.

    Rosa, R; Prehu, M O; Beuzard, Y; Rosa, J

    1978-01-01

    An inherited and complete deficiency of diphosphoglycerate mutase was discovered in the erythrocytes of a 42-yr-old man of French origin whose blood hemoglobin concentration was 19.0 g/dl. Upon physical examination he was normal with the exception of a ruddy cyanosis. The morphology of his erythrocytes was also normal and there was no evidence of hemolysis. The erythrocyte 2,3-diphosphoglycerate level was below 3% of normal values and, as a consequence, the affinity of the cells for oxygen was increased. Diphosphoglycerate mutase activity was undetectable in erythrocytes as was that of diphosphoglycerate phosphatase. The activities of all the other erythrocyte enzymes that were tested were normal except for nomophosphoglycerate mutase which was diminished to 50% of the normal value. The levels of reduced glutathione, ATP, fructose 1,6-diphosphate, and of triose phosphates were elevated, whereas those of glucose 6-phosphate and fructose 6-phosphate were decreased. This report sheds new light on the role of diphosphoglycerate mutase in the metabolism of erythrocytes. Images PMID:152321

  14. The first case of a complete deficiency of diphosphoglycerate mutase in human erythrocytes.

    Rosa, R; Prehu, M O; Beuzard, Y; Rosa, J

    1978-11-01

    An inherited and complete deficiency of diphosphoglycerate mutase was discovered in the erythrocytes of a 42-yr-old man of French origin whose blood hemoglobin concentration was 19.0 g/dl. Upon physical examination he was normal with the exception of a ruddy cyanosis. The morphology of his erythrocytes was also normal and there was no evidence of hemolysis. The erythrocyte 2,3-diphosphoglycerate level was below 3% of normal values and, as a consequence, the affinity of the cells for oxygen was increased. Diphosphoglycerate mutase activity was undetectable in erythrocytes as was that of diphosphoglycerate phosphatase. The activities of all the other erythrocyte enzymes that were tested were normal except for nomophosphoglycerate mutase which was diminished to 50% of the normal value. The levels of reduced glutathione, ATP, fructose 1,6-diphosphate, and of triose phosphates were elevated, whereas those of glucose 6-phosphate and fructose 6-phosphate were decreased. This report sheds new light on the role of diphosphoglycerate mutase in the metabolism of erythrocytes.

  15. Haemolytic effect of saponin extract from Vernonia amygdalina (bitter leaf) on human erythrocyte

    Oboh, G.

    2001-09-01

    Leaves of Veronia amygdalina were extracted using ethanol and aqueous extraction respectively. The physico-chemical analysis of the extracts revealed that both extracts had darkish brown colour, sweetish bitter taste, pungent smell, positive froth and haemolytic test, this indicated the presence of saponin in both extracts. The result of the haemolytic assay revealed that blood group-O had the highest susceptibility to the saponin-induced haemolysis, while blood group-A had the least susceptibility to haemolysis among the blood groups tested. Genotype-AA had the highest resistant to haemolysis by Vernonia amygdalina saponin induced haemolysis, while genotype-SS had the least resistant to haemolysis among the genotype tested. Furthermore the ethanol extract had a higher haemolytic activity than the aqueous extract on the various human erythrocyte analysed. This study revealed that Vernonia amygdalina had haemolytic substance, this substance had a high haemolytic effect on blood group-O and genotype-SS. The active haemolytic substance in both extracts was identified to be saponin. (author)

  16. Synthesis, characterization, and cytotoxicity in human erythrocytes of multifunctional, magnetic, and luminescent nanocrystalline rare earth fluorides

    Grzyb, Tomasz; Mrówczyńska, Lucyna; Szczeszak, Agata; Śniadecki, Zbigniew; Runowski, Marcin; Idzikowski, Bogdan; Lis, Stefan

    2015-10-01

    Multifunctional nanoparticles exhibiting red or green luminescence properties and magnetism were synthesized and thoroughly analyzed. The hydrothermal method was used for the synthesis of Eu3+- or Tb3+-doped GdF3-, NaGdF4-, and BaGdF5-based nanocrystalline materials. The X-ray diffraction patterns of the samples confirmed the desired compositions of the materials. Transmission electron microscope images revealed the different morphologies of the products, including the nanocrystal sizes, which varied from 12 nm in the case of BaGdF5-based nanoparticles to larger structures with dimensions exceeding 300 nm. All of the samples presented luminescence under ultraviolet irradiation, as well as when the samples were in the form of water colloids. The highest luminescence was observed for BaGdF5-based materials. The obtained nanoparticles exhibited paramagnetism along with probable evidence of superparamagnetic behavior at low temperatures. The particles' magnetic characteristics were also preserved for samples in the form of a suspension in distilled water. The cytotoxicity studies against the human erythrocytes indicated that the synthesized nanoparticles are non-toxic because they did not cause the red blood cells shape changes nor did they alter their membrane structure and permeabilization.

  17. Synthesis, characterization, and cytotoxicity in human erythrocytes of multifunctional, magnetic, and luminescent nanocrystalline rare earth fluorides

    Grzyb, Tomasz; Mrówczyńska, Lucyna; Szczeszak, Agata; Śniadecki, Zbigniew; Runowski, Marcin; Idzikowski, Bogdan; Lis, Stefan

    2015-01-01

    Multifunctional nanoparticles exhibiting red or green luminescence properties and magnetism were synthesized and thoroughly analyzed. The hydrothermal method was used for the synthesis of Eu 3+ - or Tb 3+ -doped GdF 3 -, NaGdF 4 -, and BaGdF 5 -based nanocrystalline materials. The X-ray diffraction patterns of the samples confirmed the desired compositions of the materials. Transmission electron microscope images revealed the different morphologies of the products, including the nanocrystal sizes, which varied from 12 nm in the case of BaGdF 5 -based nanoparticles to larger structures with dimensions exceeding 300 nm. All of the samples presented luminescence under ultraviolet irradiation, as well as when the samples were in the form of water colloids. The highest luminescence was observed for BaGdF 5 -based materials. The obtained nanoparticles exhibited paramagnetism along with probable evidence of superparamagnetic behavior at low temperatures. The particles’ magnetic characteristics were also preserved for samples in the form of a suspension in distilled water. The cytotoxicity studies against the human erythrocytes indicated that the synthesized nanoparticles are non-toxic because they did not cause the red blood cells shape changes nor did they alter their membrane structure and permeabilization

  18. Entamoeba histolytica phagocytosis of human erythrocytes involves PATMK, a member of the transmembrane kinase family.

    Douglas R Boettner

    2008-01-01

    Full Text Available Entamoeba histolytica is the cause of amebic colitis and liver abscess. This parasite induces apoptosis in host cells and utilizes exposed ligands such as phosphatidylserine to ingest the apoptotic corpses and invade deeper into host tissue. The purpose of this work was to identify amebic proteins involved in the recognition and ingestion of dead cells. A member of the transmembrane kinase family, phagosome-associated TMK96 (PATMK, was identified in a proteomic screen for early phagosomal proteins. Anti-peptide affinity-purified antibody produced against PATMK demonstrated that it was a type I integral membrane protein that was expressed on the trophozoite surface, and that co-localized with human erythrocytes at the site of contact. The role of PATMK in erythrophagocytosis in vitro was demonstrated by: (i incubation of ameba with anti-PATMK antibodies; (ii PATMK mRNA knock-down using a novel shRNA expression system; and (iii expression of a carboxy-truncation of PATMK (PATMK(delta932. Expression of the carboxy-truncation of PATMK(delta932 also caused a specific reduction in the ability of E. histolytica to establish infection in the intestinal model of amebiasis, however these amebae retained the ability to cause hepatic abscesses when directly injected in the liver. In conclusion, PATMK was identified as a member of the TMK family that participates in erythrophagocytosis and is uniquely required for intestinal infection.

  19. Entamoeba histolytica phagocytosis of human erythrocytes involves PATMK, a member of the transmembrane kinase family.

    Boettner, Douglas R; Huston, Christopher D; Linford, Alicia S; Buss, Sarah N; Houpt, Eric; Sherman, Nicholas E; Petri, William A

    2008-01-01

    Entamoeba histolytica is the cause of amebic colitis and liver abscess. This parasite induces apoptosis in host cells and utilizes exposed ligands such as phosphatidylserine to ingest the apoptotic corpses and invade deeper into host tissue. The purpose of this work was to identify amebic proteins involved in the recognition and ingestion of dead cells. A member of the transmembrane kinase family, phagosome-associated TMK96 (PATMK), was identified in a proteomic screen for early phagosomal proteins. Anti-peptide affinity-purified antibody produced against PATMK demonstrated that it was a type I integral membrane protein that was expressed on the trophozoite surface, and that co-localized with human erythrocytes at the site of contact. The role of PATMK in erythrophagocytosis in vitro was demonstrated by: (i) incubation of ameba with anti-PATMK antibodies; (ii) PATMK mRNA knock-down using a novel shRNA expression system; and (iii) expression of a carboxy-truncation of PATMK (PATMK(delta932)). Expression of the carboxy-truncation of PATMK(delta932) also caused a specific reduction in the ability of E. histolytica to establish infection in the intestinal model of amebiasis, however these amebae retained the ability to cause hepatic abscesses when directly injected in the liver. In conclusion, PATMK was identified as a member of the TMK family that participates in erythrophagocytosis and is uniquely required for intestinal infection.

  20. Inositol phosphates influence the membrane bound Ca2+/Mg2+ stimulated ATPase from human erythrocyte membranes

    Kester, M.; Ekholm, J.; Kumar, R.; Hanahan, D.J.

    1986-01-01

    The modulation by exogenous inositol phosphates of the membrane Ca 2+ /Mg 2+ ATPase from saponin/EGTA lysed human erythrocytes was determined in a buffer (pH 7.6) containing histidine, 80 mM, MgCl 2 , 3.3 mM, NaCl, 74 mM, KCl, 30 mM, Na 2 ATP, 2.3 mM, ouabain, 0.83 mM, with variable amounts of CaCl 2 and EGTA. The ATPase assay was linear with time at 44 0 C. The inositol phosphates were commercially obtained and were also prepared from 32 P labeled rabbit platelet inositol phospholipids. Inositol triphosphate (IP 3 ) elevated the Ca 2+ /Mg 2+ ATPase activity over basal levels in a dose, time, and calcium dependent manner and were increased up to 85% of control values. Activities for the Na + /K + -ATPase and a Mg 2+ ATPase were not effected by IP 3 . Ca 2+ /Mg 2+ APTase activity with IP 2 or IP 3 could be synergistically elevated with calmodulin addition. The activation of the ATPase with IP 3 was calcium dependent in a range from .001 to .02 mM. The apparent Km and Vmax values were determined for IP 3 stimulated Ca 2+ /Mg 2+ ATPase

  1. Calorimetric study on human erythrocyte glycolysis. Heat production in various metabolic conditions.

    Minakami, S; de Verdier, C H

    1976-06-01

    The heat production of human erythrocytes was measured on a flow microcalorimeter with simultaneous analyses of lactate and other metabolites. The heat production connected with the lactate formation was about 17 kcal (71 kJ) per mol lactate formed which corresponded to the sum of heat production due to the formation of lactate from glucose and the heat production due to neutralization. The heat production rate increased as the pH of the suspension increased, corresponding to the increase in lactate formation. Glycolytic inhibitors such as fluoride and monoiodoacetate caused a decrease in the rate of heat production, whereas arsenate induced a large transient increase in heat production associated with a transient increase in lactate formation. Decrease in pyruvate concentration was usually associated with increase in heat production, although the decreased pyruvate concentration was coupled with formation of 2,3-bisphosphoglycerate. When inosine, dihydroxyacetone or D-glyceraldehyde was used as a substrate, an increase in the heat production rate was observed. Addition of methylene blue caused an oxygen uptake which was accompanied by a remarkable increase in heat production rate corresponding to about 160 kcal (670 kJ) per mol oxygen consumed. The value for heat production in red cells in the above-mentioned metabolic conditions was considered in relation to earlier known data on free energy and enthalpy changes of the different metabolic steps in the glycolytic pathway.

  2. New human erythrocyte protein with binding sites for both spectrin and calmodulin

    Gardner, K.; Bennett, V.

    1986-01-01

    A new cytoskeletal protein that binds calmodulin has been purified to greater than 95% homogeneity from human erythrocyte cytoskeletons. The protein is a heterodimer with subunits of 103,000 and 97,000 and M/sub r/ = 197,000 calculated from its Stokes radius of 6.9 nm and sedimentation coefficient of 6.8. A binding affinity of this protein for calmodulin has been estimated to be 230 nM by displacement of two different concentrations of 125 I-azidocalmodulin with increasing concentrations of unmodified calmodulin followed by Dixon plot analysis. This protein is present in red cells at approximately 30,000 copies per cell and contains a very tight binding site(s) on cytoskeletons. The protein can be only partially solubilized from isolated cytoskeletons in buffers containing high salt, but can be totally solubilized from red cell ghost membranes by extraction in low ionic strength buffers. Affinity purified IgG against this calmodulin-binding protein identifies crossreacting polypeptide(s) in brain, kidney, testes and retina. Visualization of the calmodulin-binding protein by negative staining, rotary shadowing and unidirectional shadowing indicate that it is a flattened circular molecule with molecular height of 5.4 nm and a diameter of 12.4 nm. Preliminary cosedimentation studies with purified spectrin and F-actin indicate that the site of interaction of this calmodulin-binding protein with the cytoskeleton resides on spectrin

  3. Proteolytically modified human beta 2-microglobulin augments the specific cytotoxic activity in murine mixed lymphocyte culture

    Nissen, Mogens Holst; Claësson, M H

    1987-01-01

    the endogenous production of interleukin 2 in the MLC culture; monoclonal antibody which reacts with both the native beta 2-m and M-beta 2-m molecule blocks the augmentation of cytotoxic T lymphocyte production induced by M-beta 2-m; murine as well as human MLC responder cells can proteolytically modify native......A proteolytically modified form of beta 2-microglobulin (beta 2-m) present in the serum of patients suffering from autoimmune, immunodeficient diseases and cancer has been reported in the literature. In the present study we show that human beta 2-m as well as the proteolytically modified human form...... (M-beta 2-m) bind to murine lymphocytes expressing H-2 class I antigens; M-beta 2-m, when added at day 0 and 1 of culture in nanomolar concentrations to a one-way murine allogeneic mixed lymphocyte culture (MLC) augments the generation of specific cytotoxic T lymphocytes; M-beta 2-m increases...

  4. Whole blood microculture assay of human lymphocyte function.

    Pauly, J L; Han, T

    1976-11-01

    A whole blood microculture assay is described for measuring lymphocyte reactivity to mitogenic and antigenic stimulants. This assay employs heparinized whole blood, serum-free culture medium, microtiter plates, and a Multiple Automated Sample Harvester (MASH). When this assay is compared to other leukocyte assays, its major advantages include (1) the utilization of fewer lymphocytes per microculture, thuus reducing the amount of blood required per test while increasing the number of test agents and replicate cultures which can be employed in any given experiment; (2) the conservation of mitogens, antigens, drugs, enzymes, hormones, lymphokines, and other test agents, some of which are either expensive of difficult to prepare in large quantities; (3) the elimination of lymphocyte isolation and purification procedures which may disrupt the relative proportion of T cells, B cells and antigen-processing cells; and (4) the application of an automated harvester which simplifies and expedites procedures required for processing cells for liquid scintillation counting.

  5. In vitro X-ray irradiation of human peripheral blood T lymphocytes enhances suppressor function

    Ogawa, H.; Tsunematsu, T.

    1983-01-01

    The effect of in vitro X-ray irradiation on human peripheral blood T lymphocytes was studied with regard to their suppressor activity related to the concanavalin A (Con A)-induced suppressor system. To generate suppressor T lymphocytes, purified human T lymphocytes were incubated for 3 days in the first culture, with or without Con A. These lymphocytes were irradiated with various doses of X-ray before, mid or after the culture. After doing a second culture for 6 days, the suppressive influence of these cells on T lymphocyte proliferation rates stimulated with allogeneic mononuclear cells, and B lymphocyte proliferation rates stimulated with pokeweed mitogen was measured. Irradiation of cultures to which Con A had not been added induced much the same level of suppressor activity as seen in the cultures with Con A. The suppressor activity gradually increased with time from the irradiation to the suppressor cell assay. Suppressor T lymphocytes were resistant to X-ray irradiation and independent of DNA synthesis. However, irradiation-induced enhancement was minimal in cultures incubated with con A, regardless of the irradiation time. (author)

  6. Damage of chromosoms under irradiation of human blood lymphocytes and development of bystander effect.

    Shemetun, O V

    2016-12-01

    the research the distribution of radiation induced damages among chromosomes and their bands in irra diated in vitro human blood lymphocytes and in unirradiated bystander cells.Material and methods of research: cultivation of human peripheral blood lymphocytes by semi micromethod D.A. Hungerford, modeling of radiation induced bystander effect in mixed cultures consisting of irradiated in vitro and non irradiated blood lymphocytes from persons of different gender, GTG staining of metaphase chromosomes and their cytogenetic analysis. Break points in chromosomes under the formation of aberrations were identified in exposed in vitro human peripheral blood lymphocytes in doses 0.25 Gy (95 breaks in 1248 cells) and 1.0 Gy (227 breaks in 726 cells) and in non irradiated bystander cells under their joint cultivation with irradiated in vitro human lymphocytes (51 breaks in 1137 cells at irradiation of adjacent populations of lymphocytes in dose 0.25 Gy and 75 breaks in 1321 cells at irradiation of adjacent population of lymphocytes in a dose 1.0 Gy). The distribution of injuries among the chromo somes and their bands was investigated. in radiation exposed in vitro human peripheral blood lymphocytes as well as in bystander cells the fre quency of damaged bands and number of breaks which localized in them exceeded the control value (p chromosomes were damaged according to their relative length. Location of bands with increasing number of breaks coincided with the «hot spots» of chromosome damage following irradiation and fragile sites. More sensitive to damage were G negative euchromatin chromosome bands, in which were localized 82 88 % breaks. Damageability of telomeric regions in the irradiated cells had no significant difference from the control, while in bystander cells was lower than control value (p < 0.05). O. V. Shemetun.

  7. The mitogenic response of cryopreserved human lymphocytes in a microculture system.

    Steel, C M; Ennis, M; Levin, A G; Wasunna, A

    1977-01-01

    Fresh blood lymphocytes from nine health donors have been compared with samples from the same donors, recovered after period of 2 to 21 months storage in liquid nitrogen, for the capacity to respond to a range of mitogens in vitro. A microculture assay was used, requireing aliquots of only 25,000 cells. The mean levels of 14C-thymidine uptake for fresh and frozen samples were closely comparable when the cells had been stimulated by PHA, Pokeweed or mitomycin-C-treated allogeneic lymphoblastoid cells. Lymphocytes from six East African donors, frozen by a very simple technique, were recovered after 3 or more years storage in liquid nitrogen. Five of the samples were in good condition as judged by cell viability and the capacity to form spontaneous 'E' rosettes with sheep erythrocytes. These five samples also responded extremely well to PHA, PWM and mitomycin-C-treated allogeneic lymphoblastoid cells using the microculture assay. This study extends the range of applications of cell banks in which small aliquots of blood lymphocytes are stored in liquid nitrogen for periods of several years.

  8. Activated T lymphocytes disappear from circulation during endotoxemia in humans

    Suarez Krabbe, Karen; Kemp, Helle Bruunsgaard; Qvist, Jesper

    2002-01-01

    of disappearance were characterized by an activated phenotype (CD45RA(-) CD45RO(+)) as well as a phenotype linked to apoptosis (CD95(+) CD28(-)). In conclusion, endotoxin-induced lymphopenia reflects the disappearance from the circulation of activated lymphocytes prone to undergo apoptosis....

  9. In situ assembly states of (Na+,K+)-pump ATPase in human erythrocytes. Radiation target size analyses

    Hah, J.; Goldinger, J.M.; Jung, C.Y.

    1985-01-01

    The in situ assembly state of the (Na+,K+)-pump ATPase of human erythrocytes was studied by applying the classical target theory to radiation inactivation data of the ouabain-sensitive sodium efflux and ATP hydrolysis. Erythrocytes and their extensively washed white ghosts were irradiated at -45 to -50 degrees C with an increasing dose of 1.5-MeV electron beam, and after thawing, the Na+-pump flux and/or enzyme activities were assayed. Each activity measured was reduced as a simple exponential function of radiation dose, from which a radiation sensitive mass (target size) was calculated. When intact cells were used, the target sizes for the pump and for the ATPase activities were equal and approximately 620,000 daltons. The target size for the ATPase activity was reduced to approximately 320,000 daltons if the cells were pretreated with digitoxigenin. When ghosts were used, the target size for the ATPase activity was again approximately 320,000 daltons. Our target size measurements together with other information available in literature suggest that (Na+,K+)-pump ATPase may exist in human erythrocytes either as a tetramer of alpha beta or as a dimer of alpha beta in tight association with other protein mass, probably certain glycolytic enzymes, and that this tetrameric or heterocomplex association is dissociable by digitoxigenin treatment or by extensive wash during ghost preparation

  10. Decreased calcium pump expression in human erythrocytes is connected to a minor haplotype in the ATP2B4 gene.

    Zámbó, Boglárka; Várady, György; Padányi, Rita; Szabó, Edit; Németh, Adrienn; Langó, Tamás; Enyedi, Ágnes; Sarkadi, Balázs

    2017-07-01

    Plasma membrane Ca 2+ -ATPases are key calcium exporter proteins in most tissues, and PMCA4b is the main calcium transporter in the human red blood cells (RBCs). In order to assess the expression level of PMCA4b, we have developed a flow cytometry and specific antibody binding method to quantitatively detect this protein in the erythrocyte membrane. Interestingly, we found several healthy volunteers showing significantly reduced expression of RBC-PMCA4b. Western blot analysis of isolated RBC membranes confirmed this observation, and indicated that there are no compensatory alterations in other PMCA isoforms. In addition, reduced PMCA4b levels correlated with a lower calcium extrusion capacity in these erythrocytes. When exploring the potential genetic background of the reduced PMCA4b levels, we found no missense mutations in the ATP2B4 coding regions, while a formerly unrecognized minor haplotype in the predicted second promoter region closely correlated with lower erythrocyte PMCA4b protein levels. In recent GWA studies, SNPs in this ATP2B4 haplotype have been linked to reduced mean corpuscular hemoglobin concentrations (MCHC), and to protection against malaria infection. Our data suggest that an altered regulation of gene expression is responsible for the reduced RBC-PMCA4b levels that is probably linked to the development of human disease-related phenotypes. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Hypoxia activates a Ca2+-permeable cation conductance sensitive to carbon monoxide and to GsMTx-4 in human and mouse sickle erythrocytes.

    Vandorpe, David H; Xu, Chang; Shmukler, Boris E; Otterbein, Leo E; Trudel, Marie; Sachs, Frederick; Gottlieb, Philip A; Brugnara, Carlo; Alper, Seth L

    2010-01-15

    Deoxygenation of sickle erythrocytes activates a cation permeability of unknown molecular identity (Psickle), leading to elevated intracellular [Ca(2+)] ([Ca(2+)](i)) and subsequent activation of K(Ca) 3.1. The resulting erythrocyte volume decrease elevates intracellular hemoglobin S (HbSS) concentration, accelerates deoxygenation-induced HbSS polymerization, and increases the likelihood of cell sickling. Deoxygenation-induced currents sharing some properties of Psickle have been recorded from sickle erythrocytes in whole cell configuration. We now show by cell-attached and nystatin-permeabilized patch clamp recording from sickle erythrocytes of mouse and human that deoxygenation reversibly activates a Ca(2+)- and cation-permeable conductance sensitive to inhibition by Grammastola spatulata mechanotoxin-4 (GsMTx-4; 1 microM), dipyridamole (100 microM), DIDS (100 microM), and carbon monoxide (25 ppm pretreatment). Deoxygenation also elevates sickle erythrocyte [Ca(2+)](i), in a manner similarly inhibited by GsMTx-4 and by carbon monoxide. Normal human and mouse erythrocytes do not exhibit these responses to deoxygenation. Deoxygenation-induced elevation of [Ca(2+)](i) in mouse sickle erythrocytes did not require KCa3.1 activity. The electrophysiological and fluorimetric data provide compelling evidence in sickle erythrocytes of mouse and human for a deoxygenation-induced, reversible, Ca(2+)-permeable cation conductance blocked by inhibition of HbSS polymerization and by an inhibitor of strctch-activated cation channels. This cation permeability pathway is likely an important source of intracellular Ca(2+) for pathologic activation of KCa3.1 in sickle erythrocytes. Blockade of this pathway represents a novel therapeutic approach for treatment of sickle disease.

  12. Hypoxia activates a Ca2+-permeable cation conductance sensitive to carbon monoxide and to GsMTx-4 in human and mouse sickle erythrocytes.

    David H Vandorpe

    2010-01-01

    Full Text Available Deoxygenation of sickle erythrocytes activates a cation permeability of unknown molecular identity (Psickle, leading to elevated intracellular [Ca(2+] ([Ca(2+](i and subsequent activation of K(Ca 3.1. The resulting erythrocyte volume decrease elevates intracellular hemoglobin S (HbSS concentration, accelerates deoxygenation-induced HbSS polymerization, and increases the likelihood of cell sickling. Deoxygenation-induced currents sharing some properties of Psickle have been recorded from sickle erythrocytes in whole cell configuration.We now show by cell-attached and nystatin-permeabilized patch clamp recording from sickle erythrocytes of mouse and human that deoxygenation reversibly activates a Ca(2+- and cation-permeable conductance sensitive to inhibition by Grammastola spatulata mechanotoxin-4 (GsMTx-4; 1 microM, dipyridamole (100 microM, DIDS (100 microM, and carbon monoxide (25 ppm pretreatment. Deoxygenation also elevates sickle erythrocyte [Ca(2+](i, in a manner similarly inhibited by GsMTx-4 and by carbon monoxide. Normal human and mouse erythrocytes do not exhibit these responses to deoxygenation. Deoxygenation-induced elevation of [Ca(2+](i in mouse sickle erythrocytes did not require KCa3.1 activity.The electrophysiological and fluorimetric data provide compelling evidence in sickle erythrocytes of mouse and human for a deoxygenation-induced, reversible, Ca(2+-permeable cation conductance blocked by inhibition of HbSS polymerization and by an inhibitor of strctch-activated cation channels. This cation permeability pathway is likely an important source of intracellular Ca(2+ for pathologic activation of KCa3.1 in sickle erythrocytes. Blockade of this pathway represents a novel therapeutic approach for treatment of sickle disease.

  13. Plasmodium knowlesi Skeleton-Binding Protein 1 Localizes to the 'Sinton and Mulligan' Stipplings in the Cytoplasm of Monkey and Human Erythrocytes.

    Lucky, Amuza Byaruhanga; Sakaguchi, Miako; Katakai, Yuko; Kawai, Satoru; Yahata, Kazuhide; Templeton, Thomas J; Kaneko, Osamu

    2016-01-01

    The malaria parasite, Plasmodium, exports protein products to the infected erythrocyte to introduce modifications necessary for the establishment of nutrient acquisition and surface display of host interaction ligands. Erythrocyte remodeling impacts parasite virulence and disease pathology and is well documented for the human malaria parasite Plasmodium falciparum, but has been less described for other Plasmodium species. For P. falciparum, the exported protein skeleton-binding protein 1 (PfSBP1) is involved in the trafficking of erythrocyte surface ligands and localized to membranous structures within the infected erythrocyte, termed Maurer's clefts. In this study, we analyzed SBP1 orthologs across the Plasmodium genus by BLAST analysis and conserved gene synteny, which were also recently described by de Niz et al. (2016). To evaluate the localization of an SBP1 ortholog, we utilized the zoonotic malaria parasite, Plasmodium knowlesi. Immunofluorescence assay of transgenic P. knowlesi parasites expressing epitope-tagged recombinant PkSBP1 revealed a punctate staining pattern reminiscent of Maurer's clefts, following infection of either monkey or human erythrocytes. The recombinant PkSBP1-positive puncta co-localized with Giemsa-stained structures, known as 'Sinton and Mulligan' stipplings. Immunoelectron microscopy also showed that recombinant PkSBP1 localizes within or on the membranous structures akin to the Maurer's clefts. The recombinant PkSBP1 expressed in P. falciparum-infected erythrocytes co-localized with PfSBP1 at the Maurer's clefts, indicating an analogous trafficking pattern. A member of the P. knowlesi 2TM protein family was also expressed and localized to membranous structures in infected monkey erythrocytes. These results suggest that the trafficking machinery and induced erythrocyte cellular structures of P. knowlesi are similar following infection of both monkey and human erythrocytes, and are conserved with P. falciparum.

  14. Plasmodium knowlesi Skeleton-Binding Protein 1 Localizes to the ‘Sinton and Mulligan’ Stipplings in the Cytoplasm of Monkey and Human Erythrocytes

    Lucky, Amuza Byaruhanga; Sakaguchi, Miako; Katakai, Yuko; Kawai, Satoru; Yahata, Kazuhide; Templeton, Thomas J.

    2016-01-01

    The malaria parasite, Plasmodium, exports protein products to the infected erythrocyte to introduce modifications necessary for the establishment of nutrient acquisition and surface display of host interaction ligands. Erythrocyte remodeling impacts parasite virulence and disease pathology and is well documented for the human malaria parasite Plasmodium falciparum, but has been less described for other Plasmodium species. For P. falciparum, the exported protein skeleton-binding protein 1 (PfSBP1) is involved in the trafficking of erythrocyte surface ligands and localized to membranous structures within the infected erythrocyte, termed Maurer's clefts. In this study, we analyzed SBP1 orthologs across the Plasmodium genus by BLAST analysis and conserved gene synteny, which were also recently described by de Niz et al. (2016). To evaluate the localization of an SBP1 ortholog, we utilized the zoonotic malaria parasite, Plasmodium knowlesi. Immunofluorescence assay of transgenic P. knowlesi parasites expressing epitope-tagged recombinant PkSBP1 revealed a punctate staining pattern reminiscent of Maurer's clefts, following infection of either monkey or human erythrocytes. The recombinant PkSBP1-positive puncta co-localized with Giemsa-stained structures, known as ‘Sinton and Mulligan’ stipplings. Immunoelectron microscopy also showed that recombinant PkSBP1 localizes within or on the membranous structures akin to the Maurer's clefts. The recombinant PkSBP1 expressed in P. falciparum-infected erythrocytes co-localized with PfSBP1 at the Maurer's clefts, indicating an analogous trafficking pattern. A member of the P. knowlesi 2TM protein family was also expressed and localized to membranous structures in infected monkey erythrocytes. These results suggest that the trafficking machinery and induced erythrocyte cellular structures of P. knowlesi are similar following infection of both monkey and human erythrocytes, and are conserved with P. falciparum. PMID:27732628

  15. Peripheral erythrocytes decrease upon specific respiratory challenge with grass pollen allergen in sensitized mice and in human subjects.

    Galateja Jordakieva

    Full Text Available BACKGROUND AND AIMS: Specific hyper-responsiveness towards an allergen and non-specific airway hyperreactivity both impair quality of life in patients with respiratory allergic diseases. We aimed to investigate cellular responses following specific and non-specific airway challenges locally and systemically in i sensitized BALB/c mice challenged with grass pollen allergen Phl p 5, and in ii grass pollen sensitized allergic rhinitis subjects undergoing specific airway challenge in the Vienna Challenge Chamber (VCC. METHODS AND RESULTS: BALB/c mice (n = 20 were intraperitoneally immunized with grass pollen allergen Phl p 5 and afterwards aerosol challenged with either the specific allergen Phl p 5 (n = 10 or the non-specific antigen ovalbumin (OVA (n = 10. A protocol for inducing allergic asthma as well as allergic rhinitis, according to the united airway concept, was used. Both groups of exposed mice showed significantly reduced physical activity after airway challenge. Specific airway challenge further resulted in goblet cell hyperplasia, enhanced mucous secretion, intrapulmonary leukocyte infiltration and lymphoid follicle formation, associated with significant expression of IL-4, IL-5 and IL-13 in splenocytes and also partially in lung tissue. Concerning circulating blood cell dynamics, we observed a significant drop of erythrocyte counts, hemoglobin and hematocrit levels in both mouse groups, challenged with allergen or OVA. A significant decrease in circulating erythrocytes and hematocrit levels after airway challenges with grass pollen allergen was also found in grass pollen sensitized human rhinitis subjects (n = 42 at the VCC. The effects on peripheral leukocyte counts in mice and humans however were opposed, possibly due to the different primary inflammation sites. CONCLUSION: Our data revealed that, besides significant leukocyte dynamics, particularly erythrocytes are involved in acute hypersensitivity reactions to respiratory allergens

  16. Serine esterase and hemolytic activity in human cloned cytotoxic T lymphocytes

    1988-01-01

    Target cell lysis by most murine cytotoxic T lymphocytes appears to be mediated by a complement (C9)-like protein called perforin, contained in high-density cytoplasmic granules. These granules also contain high levels of serine esterase activity, which may also play a role in cytolysis. Analysis of 17 cloned human cytotoxic T lymphocytes revealed the presence of serine esterase that is very similar to its murine counterpart in substrate and inhibitor specificities, pH optimum, and molecular ...

  17. [Mechanism of changes in the rate of glycolysis and levels of ATP and 2,3-diphosphoglycerate in human erythrocytes during aging].

    Bogatskaia, L N; Pisaruk, A V

    1987-01-01

    Reasons which have induced changes in the glycolysis rate, ATP and 2,3-diphosphoglycerate content in human erythrocytes with ageing are studied. A fall of the hexokinase activity is shown to be one of the reasons of a significant decrease in the glycolysis rate. The total ATPase activity in erythrocytes does not change with the age. At the same time the decay rate of 2,3-diphosphoglycerate increases, that, evidently, is one of the reasons of the 2,3-diphosphoglycerate content decrease in erythrocytes with ageing.

  18. The orientation of eosin-5-maleimide on human erythrocyte band 3 measured by fluorescence polarization microscopy.

    Blackman, S M; Cobb, C E; Beth, A H; Piston, D W

    1996-01-01

    The dominant motional mode for membrane proteins is uniaxial rotational diffusion about the membrane normal axis, and investigations of their rotational dynamics can yield insight into both the oligomeric state of the protein and its interactions with other proteins such as the cytoskeleton. However, results from the spectroscopic methods used to study these dynamics are dependent on the orientation of the probe relative to the axis of motion. We have employed polarized fluorescence confocal microscopy to measure the orientation of eosin-5-maleimide covalently reacted with Lys-430 of human erythrocyte band 3. Steady-state polarized fluorescence images showed distinct intensity patterns, which were fit to an orientation distribution of the eosin absorption and emission dipoles relative to the membrane normal axis. This orientation was found to be unchanged by trypsin treatment, which cleaves band 3 between the integral membrane domain and the cytoskeleton-attached domain. this result suggests that phosphorescence anisotropy changes observed after trypsin treatment are due to a rotational constraint change rather than a reorientation of eosin. By coupling time-resolved prompt fluorescence anisotropy with confocal microscopy, we calculated the expected amplitudes of the e-Dt and e-4Dt terms from the uniaxial rotational diffusion model and found that the e-4Dt term should dominate the anisotropy decay. Delayed fluorescence and phosphorescence anisotropy decays of control and trypsin-treated band 3 in ghosts, analyzed as multiple uniaxially rotating populations using the amplitudes predicted by confocal microscopy, were consistent with three motional species with uniaxial correlation times ranging from 7 microseconds to 1.4 ms. Images FIGURE 4 FIGURE 8 FIGURE 9 PMID:8804603

  19. Survival and PHA-stimulation of #betta#-irradiated human peripheral blood T lymphocyte subpopulations

    Schwartz, J.L.; Darr, D.C.; Daulden, M.E.

    1983-01-01

    Human peripheral blood T lymphocyte subpopulations were identified and isolated on the basis of their ability to bind IgG (T-G), IgM (T-M), or neither immunoglobulin class (T-null). Lymphocytes were exposed to 0, 0.5, 1.0, 2.5 or 5.0 Gy of 60 Co #betta#-rays either as a T-cell suspension or as separated T cell subsets. Survival curves, determined 5 days after irradiation, revealed that each subset has radiosensitive and radioresistant portions, and that the T-G cell is the most sensitive subset. Mitotic indices of 48-h cultures showed that the response of unirradiated T lymphocytes to PHA varied greatly among the subsets, the highest indices being obtained for the T-M and the lowest for the T-G cells. With the possible exception of the T-G cells, the subsets are realtively resistant to mitotic effects of #betta#-rays. T-G cells suppress the PHA-induced mitotic response of the other T lymphocyte subsets, and this suppressor effect is radiosensitive, being abolished by 1.0 Gy. It is concluded that lymphocytes exposed to >= 1 Gy of #betta#-rays will have very few dividing B lymphocytes or T-G cells. This together with radiation-induced loss of T-G suppressor action means that the predominant lymphocyte types in mitosis after >=1 Gy are the radioresistant T-M and T-null cells. (orig.)

  20. Viscosity of concentrated solutions and of human erythrocyte cytoplasm determined from NMR measurement of molecular correlation times

    Endre, Z.H.; Kuchel, P.W.

    1986-01-01

    Metabolically active human erythrocytes were incubated with [α- 13 C]glycine which led to the specific enrichment of intracellular glutathione. The cells were then studied using 13 C-NMR in which the longitudinal relaxation times (T 1 ) and nuclear Overhauser enhancements of the free glycine and glutathione were measured. Bulk viscosities of the erythrocyte cytoplasm were measured using Ostwald capillary viscometry. Large differences existed between the latter viscosity estimates and those based upon NMR-T 1 measurements. The authors derived an equation from the theory of the viscosity of concentrated solutions which contains two phenomenological interaction parameters, a 'shape' factor and a 'volume' factor; it was fitted to data relating to the concentration dependence of viscosity measured by both methods. Under various conditions of extracellular osmotic pressure, erythrocytes change volume and thus the viscosity of the intracellular milieu is altered. The volume changes resulted in changes in the T 1 of [α- 13 C]glycine. Conversely, the authors showed that alterations in T 1 , when appropriately calibrated, could be used for monitoring changes in volume of metabolically active cells. (Auth.)

  1. Photoaffinity labeling of the human erythrocyte monosaccharide transporter with an aryl azide derivative of D-glucose

    Shanahan, M.F.; Wadzinski, B.E.; Lowndes, J.M.; Ruoho, A.E.

    1985-01-01

    A photoreactive, radioiodinated derivative of glucose, N-(4-iodoazidosalicyl)-6-amido-6-deoxyglucopyranose (IASA-glc), has been synthesized and used as a photoaffinity label for the human erythrocyte monosaccharide transporter. Photoinactivation and photoinsertion are both light-dependent and result in a marked decrease in the absorption spectra of the compound. When [ 125 I]IASA-glc was photolyzed with erythrocyte ghost membranes, photoinsertion of radiolabel was observed in three major regions, spectrin, band 3, and a protein of 58,000 daltons located in the zone 4.5 region. Of the three regions which were photolabeled, only labeling of polypeptides in the zone 4.5 region was partially blocked by D-glucose. In the non-iodinated form, N-(4-azidosalicyl)-6-amido-6-deoxy-glucopyranose inhibited the labeling of the transporter by [ 125 I]IASA-glc more effectively than D-glucose. The ability to synthesize this [ 125 I]containing photoprobe for the monosaccharide transporter at carrier-free levels offers several new advantages for investigating the structure of this transport protein in the erythrocyte

  2. The Plasmodium falciparum erythrocyte invasion ligand Pfrh4 as a target of functional and protective human antibodies against malaria.

    Linda Reiling

    Full Text Available BACKGROUND: Acquired antibodies are important in human immunity to malaria, but key targets remain largely unknown. Plasmodium falciparum reticulocyte-binding-homologue-4 (PfRh4 is important for invasion of human erythrocytes and may therefore be a target of protective immunity. METHODS: IgG and IgG subclass-specific responses against different regions of PfRh4 were determined in a longitudinal cohort of 206 children in Papua New Guinea (PNG. Human PfRh4 antibodies were tested for functional invasion-inhibitory activity, and expression of PfRh4 by P. falciparum isolates and sequence polymorphisms were determined. RESULTS: Antibodies to PfRh4 were acquired by children exposed to P. falciparum malaria, were predominantly comprised of IgG1 and IgG3 subclasses, and were associated with increasing age and active parasitemia. High levels of antibodies, particularly IgG3, were strongly predictive of protection against clinical malaria and high-density parasitemia. Human affinity-purified antibodies to the binding region of PfRh4 effectively inhibited erythrocyte invasion by P. falciparum merozoites and antibody levels in protected children were at functionally-active concentrations. Although expression of PfRh4 can vary, PfRh4 protein was expressed by most isolates derived from the cohort and showed limited sequence polymorphism. CONCLUSIONS: Evidence suggests that PfRh4 is a target of antibodies that contribute to protective immunity to malaria by inhibiting erythrocyte invasion and preventing high density parasitemia. These findings advance our understanding of the targets and mechanisms of human immunity and evaluating the potential of PfRh4 as a component of candidate malaria vaccines.

  3. Photolabeling and radioligand binding of human erythrocyte NaK-ATPase with 125I-derivatives of cymarin and digitoxigenin

    Lowndes, J.M.

    1988-01-01

    NaK-ATPase is an enzyme which maintains Na + and K + gradients across the plasma membrane of eukaryotic cells, and is specifically inhibited by cardiac glycosides. The cardiac glycoside binding site is located primarily on the catalytic α subunit but the glycoprotein β and proteolipid-γ subunits may also contribute to the structure of the site. In order to label the cardiac glycoside binding site of human erythrocytes, four photoaffinity ligands with very high specific radioactivity were synthesized. The compounds, which are abbreviated [ 125 I]AISC, [ 125 I]AIPP-GluD, [ 125 I]AIPP-GalD and [ 125 I]IA-GalD, were all effective photolabels for NaK-ATPase as shown by ouabain-protectable, covalent labeling of the α, β, and proteolipid-γ subunits. In order to study the possible existence of a very high affinity binding site in erythrocyte NaK-ATPase, a carrier-free radioligand, [ 125 I]I-TASC, was synthesized; this compound had the same structure as [ 125 I]AISC except that a light-sensitive azide group was replaced with a hydroxyl group. Competitive binding assays with cymarin against 0.2 nM [ 125 I]I-TASC suggested two classes of erythrocyte binding sites. Scatchard analysis of direct [ 125 I]I-TASC binding indicated that the very high affinity, low capacity class of erythrocyte bindings sites had a K D of 54 pM and a B max of 23 fmol/mg protein

  4. The Duffy binding protein (PkDBPαII) of Plasmodium knowlesi from Peninsular Malaysia and Malaysian Borneo show different binding activity level to human erythrocytes.

    Lim, Khai Lone; Amir, Amirah; Lau, Yee Ling; Fong, Mun Yik

    2017-08-11

    The zoonotic Plasmodium knowlesi is a major cause of human malaria in Malaysia. This parasite uses the Duffy binding protein (PkDBPαII) to interact with the Duffy antigen receptor for chemokines (DARC) receptor on human and macaque erythrocytes to initiate invasion. Previous studies on P. knowlesi have reported distinct Peninsular Malaysia and Malaysian Borneo PkDBPαII haplotypes. In the present study, the differential binding activity of these haplotypes with human and macaque (Macaca fascicularis) erythrocytes was investigated. The PkDBPαII of Peninsular Malaysia and Malaysian Borneo were expressed on the surface of COS-7 cells and tested with human and monkey erythrocytes, with and without anti-Fy6 (anti-Duffy) monoclonal antibody treatment. Binding activity level was determined by counting the number of rosettes formed between the transfected COS-7 cells and the erythrocytes. Anti-Fy6 treatment was shown to completely block the binding of human erythrocytes with the transfected COS-7 cells, thus verifying the specific binding of human DARC with PkDBPαII. Interestingly, the PkDBPαII of Peninsular Malaysia displayed a higher binding activity with human erythrocytes when compared with the Malaysian Borneo PkDBPαII haplotype (mean number of rosettes formed = 156.89 ± 6.62 and 46.00 ± 3.57, respectively; P < 0.0001). However, no difference in binding activity level was seen in the binding assay using M. fascicularis erythrocytes. This study is the first report of phenotypic difference between PkDBPαII haplotypes. The biological implication of this finding is yet to be determined. Therefore, further studies need to be carried out to determine whether this differential binding level can be associated with severity of knowlesi malaria in human.

  5. Phosphatidylinositol response and proliferation of oxidative enzyme-activated human T lymphocytes: suppression by plasma lipoproteins

    Akeson, A.L.; Scupham, D.W.; Harmony, J.A.

    1984-01-01

    The phosphatidylinositol (PI) response and DNA synthesis of neuraminidase and galactose oxidase (NAGO)-stimulated human T lymphocytes are suppressed by low density lipoproteins (LDL). To understand the mechanism of lymphocyte activation more fully, the PI response and DNA synthesis and suppression of these events by LDL in NAGO-stimulated T lymphocytes were characterized. Between 30 min and 6 hr after NAGO stimulation, there was an increase of 32 Pi incorporation into PI without increased incorporation into the phosphorylated forms of PI or into other phospholipids. DNA synthesis as determined by [ 3 H]thymidine incorporation depended on the lymphocyte-accessory monocyte ratio and total cell density. Optimal stimulation of the PI response and DNA synthesis occurred at the same concentration of neuraminidase and galactose oxidase. While the PI response was only partially suppressed by LDL with optimal suppression at 10 to 20 micrograms of protein/ml, DNA synthesis was completely suppressed although at much higher LDL concentrations, greater than 100 micrograms protein/ml. As monocyte numbers are increased, LDL suppression of DNA synthesis is decreased. The ability of NAGO to stimulate the PI response and DNA synthesis in a similar way, and the suppression of both events by LDL, suggests the PI response is important for lymphocyte activation and proliferation. Stimulation of human T lymphocytes by oxidative mitogens, neuraminidase, and galactose oxidase caused increased phosphatidylinositol metabolism and increased DNA synthesis. Both responses were suppressed by low density lipoproteins

  6. The skin immune system (SIS): distribution and immunophenotype of lymphocyte subpopulations in normal human skin

    Bos, J. D.; Zonneveld, I.; Das, P. K.; Krieg, S. R.; van der Loos, C. M.; Kapsenberg, M. L.

    1987-01-01

    The complexity of immune response-associated cells present in normal human skin was recently redefined as the skin immune system (SIS). In the present study, the exact immunophenotypes of lymphocyte subpopulations with their localizations in normal human skin were determined quantitatively. B cells

  7. Species differences in the effect of pregnancy on lymphocyte cytokine production between human and rat

    Faas, Marijke M.; Bouman, Annechien; Veenstra van Nieuwenhoven, Angelique L.; van der Schaaf, Gerda; Moes, Henk; Heineman, Maas Jan; de Vos, Paul

    2005-01-01

    In the present study, we evaluated whether lymphocyte cytokine production during human and rat pregnancy shifts toward T helper cell type 2 (Th2) cytokine production. Therefore, blood samples were taken during the follicular and luteal phase and during pregnancy in rats and humans. Whole blood was

  8. Enzymatic methylation of band 3 anion transporter in intact human erythrocytes

    Lou, L.L.; Clarke, S.

    1987-01-01

    Band 3, the anion transport protein of erythrocyte membranes, is a major methyl-accepting substrate of the intracellular erythrocyte protein carboxyl methyltransferase (S-adenosyl-L-methionine: protein-D-aspartate O-methyltransferase; EC 2.1.1.77). The localization of methylation sites in intact cells by analysis of proteolytic fragments indicated that sites were present in the cytoplasmic N-terminal domain as well as the membranous C-terminal portion of the polypeptide. The amino acid residues that serve as carboxyl methylation sites of the erythrocyte anion transporter were also investigated. 3 H-Methylated band 3 was purified from intact erythrocytes incubated with L-[methyl- 3 H]methionine and from trypsinized and lysed erythrocytes incubated with S-adenosyl-L-[methyl- 3 H]methionine. After proteolytic digestion with carboxypeptidase Y, D-aspartic acid beta-[ 3 H]methyl ester was isolated in low yields (9% and 1%, respectively) from each preparation. The bulk of the radioactivity was recovered as [ 3 H]methanol, and the amino acid residue(s) originally associated with these methyl groups could not be determined. No L-aspartic acid beta-[ 3 H]methyl ester or glutamyl gamma-[ 3 H]methyl ester was detected. The formation of D-aspartic acid beta-[ 3 H]methyl esters in this protein in intact cells resulted from protein carboxyl methyltransferase activity since it was inhibited by adenosine and homocysteine thiolactone, which increases the intracellular concentration of the potent product inhibitor S-adenosylhomocysteine, and cycloleucine, which prevents the formation of the substrate S-adenosyl-L-[methyl- 3 H]methionine

  9. Arctigenin from Arctium lappa inhibits interleukin-2 and interferon gene expression in primary human T lymphocytes

    2011-01-01

    Background Arctium lappa (Niubang), a Chinese herbal medicine, is used to treat tissue inflammation. This study investigates the effects of arctigenin (AC), isolated from A. lappa, on anti-CD3/CD28 Ab-stimulated cell proliferation and cytokine gene expression in primary human T lymphocytes. Methods Cell proliferation was determined with enzyme immunoassays and the tritiated thymidine uptake method. Cytokine production and gene expression were analyzed with reverse transcription-polymerase chain reaction. Results AC inhibited primary human T lymphocytes proliferation activated by anti-CD3/CD28 Ab. Cell viability test indicated that the inhibitory effects of AC on primary human T lymphocyte proliferation were not due to direct cytotoxicity. AC suppressed interleukin-2 (IL-2) and interferon-γ (IFN-γ) production in a concentration-dependent manner. Furthermore, AC decreased the IL-2 and IFN-γ gene expression in primary human T lymphocytes induced by anti-CD3/CD28 Ab. Reporter gene analyses revealed that AC decreased NF-AT-mediated reporter gene expression. Conclusion AC inhibited T lymphocyte proliferation and decreased the gene expression of IL-2, IFN-γ and NF-AT. PMID:21435270

  10. Arctigenin from Arctium lappa inhibits interleukin-2 and interferon gene expression in primary human T lymphocytes.

    Tsai, Wei-Jern; Chang, Chu-Ting; Wang, Guei-Jane; Lee, Tzong-Huei; Chang, Shwu-Fen; Lu, Shao-Chun; Kuo, Yuh-Chi

    2011-03-25

    Arctium lappa (Niubang), a Chinese herbal medicine, is used to treat tissue inflammation. This study investigates the effects of arctigenin (AC), isolated from A. lappa, on anti-CD3/CD28 Ab-stimulated cell proliferation and cytokine gene expression in primary human T lymphocytes. Cell proliferation was determined with enzyme immunoassays and the tritiated thymidine uptake method. Cytokine production and gene expression were analyzed with reverse transcription-polymerase chain reaction. AC inhibited primary human T lymphocytes proliferation activated by anti-CD3/CD28 Ab. Cell viability test indicated that the inhibitory effects of AC on primary human T lymphocyte proliferation were not due to direct cytotoxicity. AC suppressed interleukin-2 (IL-2) and interferon-γ (IFN-γ) production in a concentration-dependent manner. Furthermore, AC decreased the IL-2 and IFN-γ gene expression in primary human T lymphocytes induced by anti-CD3/CD28 Ab. Reporter gene analyses revealed that AC decreased NF-AT-mediated reporter gene expression. AC inhibited T lymphocyte proliferation and decreased the gene expression of IL-2, IFN-γ and NF-AT.

  11. Arctigenin from Arctium lappa inhibits interleukin-2 and interferon gene expression in primary human T lymphocytes

    Chang Shwu-Fen

    2011-03-01

    Full Text Available Abstract Background Arctium lappa (Niubang, a Chinese herbal medicine, is used to treat tissue inflammation. This study investigates the effects of arctigenin (AC, isolated from A. lappa, on anti-CD3/CD28 Ab-stimulated cell proliferation and cytokine gene expression in primary human T lymphocytes. Methods Cell proliferation was determined with enzyme immunoassays and the tritiated thymidine uptake method. Cytokine production and gene expression were analyzed with reverse transcription-polymerase chain reaction. Results AC inhibited primary human T lymphocytes proliferation activated by anti-CD3/CD28 Ab. Cell viability test indicated that the inhibitory effects of AC on primary human T lymphocyte proliferation were not due to direct cytotoxicity. AC suppressed interleukin-2 (IL-2 and interferon-γ (IFN-γ production in a concentration-dependent manner. Furthermore, AC decreased the IL-2 and IFN-γ gene expression in primary human T lymphocytes induced by anti-CD3/CD28 Ab. Reporter gene analyses revealed that AC decreased NF-AT-mediated reporter gene expression. Conclusion AC inhibited T lymphocyte proliferation and decreased the gene expression of IL-2, IFN-γ and NF-AT.

  12. Light microscope observation of circulating human lymphocytes cultured in vitro

    Naila Francis Paulo de Oliveira

    2010-10-01

    Full Text Available The purpose of this work was to study the isolation and a light microscopy technique for cultured lymphocytes. Blood samples were obtained by venipuncture with an anticoagulant added and centrifuged in a Percoll density gradient to separate the leukocytes. Lymphocytes were placed in 25 cm ³ tissue culture flasks at 37ºC. After culturing, they were fixed and stained with the methods used for blood smears. Results showed that not all fixing solutions and stains were an equally good choice for cultured lymphocytes.Os linfócitos são células importantes do sistema imune e têm sido largamente utilizados em estudos morfológicos. Entretanto, a literatura sobre técnicas de preparação dessas células é escassa e antiga, especialmente para linfócitos cultivados in vitro. Portanto, o objetivo desse estudo foi relatar com detalhes as técnicas de isolamento e microscopia de luz de linfócitos mantidos em cultura. Amostras de sangue foram obtidas por punção venosa e centrifugadas em gradiente de densidade de Percoll, para separar os leucócitos. Os linfócitos foram mantidos em frascos de cultura de 25 cm³ a 37ºC. Após a cultura, as células foram fixadas e coradas de acordo com a metodologia utilizada para esfregaços sanguíneos. Nossos resultados mostraram que nem todos os fixadores e corantes utilizados para esfregaços sanguíneos são uma boa escolha para linfócitos cultivados in vitro.

  13. Assessment of in vitro genotoxic and cytotoxic effects of flurbiprofen on human cultured lymphocytes.

    Timocin, Taygun; Ila, Hasan Basri; Dordu, Tuba; Husunet, Mehmet Tahir; Tazehkand, Mostafa Norizadeh; Valipour, Ebrahim; Topaktas, Mehmet

    2016-01-01

    Flurbiprofen is non-steroidal anti-inflammatory drug which is commonly used for its analgesic, antipyretic, and anti-inflammatory effects. The purpose of the study was to explore the genotoxic and cytotoxic effects of flurbiprofen in human cultured lymphocytes by sister chromatid exchange, chromosome aberration, and cytokinesis-blocked micronucleus tests. 10, 20, 30, and 40 μg/mL concentrations of flurbiprofen (solvent is DMSO) were used to treatment of human cultured lymphocytes at two different treatment periods (24 and 48 h). Flurbiprofen had no significant genotoxic effect in any of these tests. But exposing to flurbiprofen for 24 and 48 h led to significant decrease on proliferation index, mitotic index, and nuclear division index (NDI). Also, all decreases were concentration-dependent (except NDI at 24 h treatment period). Consequently, the findings of this research showed that flurbiprofen had cytotoxic effects in human blood lymphocytes.

  14. Quality control of insulin radioreceptor assay for human erythrocytes. Effect of ageing of mono-125I-Tyr-A14-insulin preparation

    Marttinen, A.; Pasternack, A.; Koivula, T.; Jokela, H.; Lehtinen, M.

    1984-01-01

    The quality control of insulin radioreceptor assay for human erythrocytes is based on the storage of erythrocyte preparations in Hepes buffer of pH 8.0, containing 10 g/l of albumin and 20 mmol/l of glucose. The change of erythrocytes into spherocytes and crenated cells reduces the apparent number of insulin receptors in a relatively constant way by less than 8% a week after 10 days of storage. At the same time the dissociation constants of the insulin-receptor complex increase rapidly. Thus the use of a preparation must be limited to controlling the determination of the insulin binding sites of erythrocytes, and not to the measurement of the affinities of the receptors. When mono- 125 I-Tyr-A14-insulin gets old, a slow decrease in the insulin binding sites can be measured, but the dissociation constants of the insulin receptor complex are not affected. (author)

  15. Quality control of insulin radioreceptor assay for human erythrocytes. Effect of ageing of mono-/sup 125/I-Tyr-A14-insulin preparation

    Marttinen, A; Pasternack, A [Tampere Univ. (Finland). Dept. of Clinical Sciences; Koivula, T; Jokela, H; Lehtinen, M [Tampere Univ. Central Hospital (Finland). Dept. of Clinical Chemistry

    1984-09-01

    The quality control of insulin radioreceptor assay for human erythrocytes is based on the storage of erythrocyte preparations in Hepes buffer of pH 8.0, containing 10 g/l of albumin and 20 mmol/l of glucose. The change of erythrocytes into spherocytes and crenated cells reduces the apparent number of insulin receptors in a relatively constant way by less than 8% a week after 10 days of storage. At the same time the dissociation constants of the insulin-receptor complex increase rapidly. Thus the use of a preparation must be limited to controlling the determination of the insulin binding sites of erythrocytes, and not to the measurement of the affinities of the receptors. When mono-/sup 125/I-Tyr-A14-insulin gets old, a slow decrease in the insulin binding sites can be measured, but the dissociation constants of the insulin receptor complex are not affected.

  16. Investigation of micronuclei induction in human peripheral blood lymphocytes exposed in vitro to EMF RF

    Kolomiets, Irina A.; Triapitsina, Galina A.; Polevik, Nikolai D.; Pryakhin, Evgeny A.

    2008-01-01

    Full text: The widespread application of cellular phones is of great concern in view possible consequences for human health. The aim of this study is to assess the capability of electromagnetic fields (EMF) RF with frequency 925 MHz and modulation 217 Hz to induce genotoxic effects as evaluated by the in vitro micronucleus assay on peripheral blood lymphocytes. The flasks of peripheral blood samples collected from healthy volunteers (5 men and 5 women) were placed just on the oscillator of emitting antenna. The signals were produced by the laboratory research plant and were evaluated at four specific absorption rates (SARs) - 0; 0.29; 1.2; 8.1 W/kg. SARs were determined by the calorimetric method. Phytohaemagglutinin stimulated lymphocytes were exposed three times for 10 minutes in the G o (the first 30 minutes after the beginning of cultivation), S (24 hours later), G 2 -M (after 48 hours from the beginning of cultivation) stages of the cell cycle. 72-hours cultures of lymphocytes were examined to determine the extent of micronuclei. The Mann-Whitney U-test was used to evaluate the significance for comparison. The data indicated a significant increase of micronuclei in human lymphocytes exposed to EMF RF (6.5 ± 0.51 0/00; 7.1 ± 0.66 0/00; 7.0 ± 0.50 0/00) in comparison with sham-exposed lymphocytes (3.0 ± 0.60 0/00). There was not revealed a dose-dependent increase of micronuclei in human lymphocytes. It was suggested that the increase of micronuclei in lymphocytes is explicated by a particularity of EMF RF just near the oscillator of emitting antenna. (author)

  17. Radioprotective Effect of Achillea millefolium L Against Genotoxicity Induced by Ionizing Radiation in Human Normal Lymphocytes

    Somayeh Shahani

    2015-04-01

    Full Text Available The radioprotective effect of Achillea millefolium L (ACM extract was investigated against genotoxicity induced by ionizing radiation (IR in human lymphocytes. Peripheral blood samples were collected from human volunteers and incubated with the methanolic extract of ACM at different concentrations (10, 50, 100, and 200 μg/mL for 2 hours. At each dose point, the whole blood was exposed in vitro to 2.5 Gy of X-ray and then the lymphocytes were cultured with mitogenic stimulation to determine the micronuclei in cytokinesis-blocked binucleated cell. Antioxidant capacity of the extract was determined using free radical-scavenging method. The treatment of lymphocytes with the extract showed a significant decrease in the incidence of micronuclei binucleated cells, as compared with similarly irradiated lymphocytes without any extract treatment. The maximum protection and decrease in frequency of micronuclei were observed at 200 μg/mL of ACM extract which completely protected genotoxicity induced by IR in human lymphocytes. Achillea millefolium extract exhibited concentration-dependent radical-scavenging activity on 1,1-diphenyl-2-picryl hydrazyl free radicals. These data suggest that the methanolic extract of ACM may play an important role in the protection of normal tissues against genetic damage induced by IR.

  18. Relative biological effectiveness of tritiated water on human chromosomes of lymphocytes and bone marrow cells

    Tanaka, Kimio; Sawada, Shozo; Kamada, Nanao

    1992-01-01

    One of the major toxic effluent from nuclear power industries is tritiated water (HTO), which is released into the environment in large quantities. Low dose radiation effects and dose rate effects of HTO on human lymphocytes and bone marrow cells are not well studied. The present study was performed to investigate dose-response relationship for chromosome aberration frequencies in the human lymphocytes and bone marrow cells, by HTO in-vitro exposure at low dose ranges of 0.1 to 1 Gy. Go lymphocytes and bone marrow cells were incubated for 10 - 150 minutes with HTO at 2 cGy/min. Also 60 Co γ and 137 Cs γ rays were used as controls. Dicentric chromosomes were scored in 1,000 to 2,000 cells of each experimental series. The RBE values of HTO at low dose range for the induction of dicentric chromosomes and chromatid type aberrations were 2.7 in lymphocytes and approximately 3.8 in bone marrow cells with respect to 60 Co γ ray, respectively. Also lymphocytes were chronically exposed to HTO for 24 to 72 hrs at lower dose rates (0.2 and 0.05 cGy/min). The yields of dicentrics and rings decreased with the reduction in the dose rate of HTO, presenting a clear dose rate effects of HTO. These results provide an useful information for the assessment for health risk in humans exposed to low concentration level to HTO. (author)

  19. The Effect of a Grape Seed Extract on Radiation-Induced DNA Damage in Human Lymphocytes

    Dicu, Tiberius; Postescu, Ion D.; Foriş, Vasile; Brie, Ioana; Fischer-Fodor, Eva; Cernea, Valentin; Moldovan, Mircea; Cosma, Constantin

    2009-05-01

    Plant-derived antioxidants due to their phenolic compounds content are reported as potential candidates for reducing the levels of oxidative stress in living organisms. Grape seed extracts are very potent antioxidants and exhibit numerous interesting pharmacologic activities. Hydroethanolic (50/50, v/v) standardized extract was obtained from red grape seed (Vitis vinifera, variety Burgund Mare—BM). The total polyphenols content was evaluated by Folin-Ciocalteu procedure and expressed as μEq Gallic Acid/ml. The aim of this study was to evaluate the potential antioxidant effects of different concentrations of BM extract against 60Co γ-rays induced DNA damage in human lymphocytes. Samples of human lymphocytes were incubated with BM extract (12.5, 25.0 and 37.5 μEq GA/ml, respectively) administered at 30 minutes before in vitro irradiation with γ-rays (2 Gy). The DNA damage and repair in lymphocytes were evaluated using alkaline comet assay. Using the lesion score, the radiation-induced DNA damage was found to be significantly different (pextract (except the lymphocytes treated with 37.5 μEq GA/ml BM extract). DNA repair analyzed by incubating the irradiated cells at 37° C and 5% CO2 atmosphere for 2 h, indicated a significant difference (pextract, immediately and two hours after irradiation. These results suggest radioprotective effects after treatment with BM extract in human lymphocytes.

  20. Immunoregulatory and antioxidant performance of alpha-tocopherol and selenium on human lymphocytes.

    Lee, Chung-Yung Jetty; Wan, Jennifer Man-Fan

    2002-05-01

    The role of alpha-tocopherol (alpha-toco) and selenium (Se) on human lymphocyte oxidative stress and T-cells proliferation were studied by flow cytometry. We measured the hydrogen peroxide and glutathione levels in cultured human T-lymphocytes and the proliferation of their subsets: T-helper/inducer, T-suppressor/cytotoxic, and natural killer and interleukin-2 receptors upon stimulation by the mitogens phytohemaglutinin (PHA) and lipopolysaccharide (LPS). The results indicate that early stimulation by mitogens is affected by the glutathione and hydrogen peroxide status of the T-lymphocytes. The addition of 100 microM or 500 microM alpha-toco or 0.5 microM Se alone shows weak antioxidant and immunostimulant properties. When combined, an enhanced antioxidant and immunoregulatory effect was observed. The present findings indicate that alpha-toco and Se have interactive effects as oxygen radical scavengers, thus promoting human lymphocyte response to antigens. This suggests that micronutrient status is an important factor in considering when interpreting the results of in vitro assays of lymphocyte function.

  1. Effects of cyclophosphamide on in vitro human lymphocyte culture and mitogenic stimulation

    Sharma, B.S.

    1983-01-01

    Cyclophosphamide (CY) has been reported to be inactive in vitro under certain conditions. In the present study, CY was tested for its ability to inhibit human lymphocyte proliferation and to modulate lymphocyte response to mitogens in vitro. The inhibition of or the increase in 3 H-thymidine incorporation in mitogen-stimulated and unstimulated lymphocytes by CY was used as a measure of CY activity in vitro. The results demonstrate that lymphocytes from 10 different persons had a mean decrease of 74% in 3 H-thymidine incorporation in the presence of CY (P less than 0.005). The effect was maximal at a concentration of 160 micrograms/ml. A mean inhibition of 35 and 55% was caused by 10 and 40 micrograms/ml concentrations of CY, respectively. CY also was able to reduce the number of viable cells during 5 days in culture and had a profound effect on mitogen stimulation of lymphocytes. In all cases, CY modulated the stimulation of lymphocytes by phytohemagglutinin (PHA), concanavalin A (Con A), and pokeweed mitogen (PWM) either by augmenting or suppressing the responses. At low concentrations (10 micrograms/ml) it augmented mitogenic stimulation by 46 to 281%. At higher concentrations (20 to 160 micrograms/ml), CY had a suppressive effect with a maximum suppression of 99%. The CY-induced immunomodulation is perhaps caused by its action on the regulatory T cells. When tested in vitro, CY had inhibitory activity on T cells

  2. Edaravone protects human peripheral blood lymphocytes from γ-irradiation-induced apoptosis and DNA damage.

    Chen, Liming; Liu, Yinghui; Dong, Liangliang; Chu, Xiaoxia

    2015-03-01

    Radiation-induced cellular injury is attributed primarily to the harmful effects of free radicals, which play a key role in irradiation-induced apoptosis. In this study, we investigated the radioprotective efficacy of edaravone, a licensed clinical drug and a powerful free radical scavenger that has been tested against γ-irradiation-induced cellular damage in cultured human peripheral blood lymphocytes in studies of various diseases. Edaravone was pre-incubated with lymphocytes for 2 h prior to γ-irradiation. It was found that pretreatment with edaravone increased cell viability and inhibited generation of γ-radiation-induced reactive oxygen species (ROS) in lymphocytes exposed to 3 Gy γ-radiation. In addition, γ-radiation decreased antioxidant enzymatic activity, such as superoxide dismutase and glutathione peroxidase, as well as the level of reduced glutathione. Conversely, treatment with 100 μM edaravone prior to irradiation improved antioxidant enzyme activity and increased reduced glutathione levels in irradiated lymphocytes. Importantly, we also report that edaravone reduced γ-irradiation-induced apoptosis through downregulation of Bax, upregulation of Bcl-2, and consequent reduction of the Bax:Bcl-2 ratio. The current study shows edaravone to be an effective radioprotector against γ-irradiation-induced cellular damage in lymphocytes in vitro. Finally, edaravone pretreatment significantly reduced DNA damage in γ-irradiated lymphocytes, as measured by comet assay (% tail DNA, tail length, tail moment, and olive tail moment) (p edaravone offers protection from radiation-induced cytogenetic alterations.

  3. Influence factors of human T lymphocyte co-stimulatory effect in vitro

    Zhou Jianhua; Su Liaoyuan; Tong Jian; Xue Lian

    2000-01-01

    Objective: Effects of CD3 McAb, CD28 McAb, PHA and low-dose γ-ray irradiation on T lymphocytes were investigated to explore factors of influencing T cell signals transduction. Method: Using CD3 McAb and CD28 McAb mimicking as the first and the second signals, and using PHA and low dose γ-rays irradiation as stimulatory factors in T cell activation, the influences of these factors and the two signals on human lymphocyte proliferation response were studied with 3 H-thymidine incorporation. Results: Lymphocyte proliferation response occurred when the two signals were treated co-stimulation or within certain intervals (within 40h). PHA and 10 cGy γ-rays irradiation can also activate lymphocytes to proliferate. However, each of the two signals alone did not activate lymphocytes to proliferate. Conclusion: CD3 McAb, CD28 McAb, PHA and low-dose γ-rays irradiation could stimulate T lymphocyte proliferation, which is an important aspect in cellular immune regulation

  4. Induction of mitotic micronuclei by X-ray contrast media in human peripheral lymphocytes

    Parvez, Z.; Moncada, R.; Kormano, M.; Satokari, K.; Eklund, R.

    1987-01-01

    In vitro and in vivo cytogenetic effects of X-ray contrast media (CM) were determined by scoring micronuclei (MN) in 72-h cultures of human peripheral lymphocytes. Both ionic (sodium meglumine diatrizoate, methylglucamine diatrizoate, and sodium meglumine ioxaglate and nonionic CM (iosimide, iopromide, iohexol and iotrolan) were able to induce MN in lymphocytes. Based upon their calculated percent probabilities for MN induction, these agents could be ranked in their decreasing order of probability, as iosimide > sodium meglumine ioxaglate > iohexol > sodium meglumine diatrizoate > iopromide > methylglucamine diatrizoate > iotrolan. Stepwise logistic regression analysis of the data indicated that the frequency of MN in CM-exposed lymphocyte cultures was significantly higher than the frequency of MN in control cultures (P < 0.001). In clinical studies where 14 patients were injected with an ionic CM methylglucamine diatrizoate, lymphocyte cultures from 10 patients showed higher frequencies of MN. The differences between pre- and post-CM counts of MN were significant in a Mann-Whitney U test (P < 0.05). The effect of X-irradiation on MN formation in lymphocytes was separately determined and was found to be insignificant. These results indicate that irrespective of ionic and osmolality differences, X-ray contrast agents are capable of producing chromosomal damage in peripheral lymphocytes. Further studies are required to establish molecular mechanisms in the observed cytogenetic effects of CM in cell cultures. (Auth.)

  5. Effects of exogenous and endogenous IL-2 on irradiated human peripheral blood lymphocytes

    Zhang Lansheng; Wang Ninghai; Luan Meiling

    1993-08-01

    Human peripheral blood lymphocytes were irradiated with 1 to 40 Gy of γ-ray, and then cultured with PHA to prepare supernatant containing IL-2 for observation of kinetics of endogenous IL-2 production and reversion of lymphocyte proliferation after adding a highly purified IL-2. IL-2 activity was determined by the ability to sustain IL-2 dependent cell line (CTLL), lymphocyte proliferation was determined by 3 H-TdR incorporation and T lymphocyte subsets by monoclonal antibodies. The experimental results showed that lymphocytes exposed to 60 Co synthesized less DNA than nonirradiated lymphocytes. The inhibitory effect can partially reversed by purified IL-2 at the γ-ray dose range of 1 to 10 Gy, while irradiation with 2.5 Gy resulted in a reduction of T cells and T subsets, and increase in CD + 4 /CD + 8 ratio. The ratio of subsets recovered after adding IL-2. The kinetics of IL-2 production showed that the endogenous IL-2 production rose markedly with increasing dose of irradiation at the range of 1 to 10 Gy, and the peak of IL-2 production was at the γ-ray dose of 10 Gy

  6. The comparison of radiosensitivity of human lymphocytes stimulated with PHA Con A and PWM

    Geng Yongzhi; Su Liaoyuan

    1989-11-01

    The transformation, DNA strand breaks and its repair ability in human peripheral blood lymphocytes stimulated with PHA, Con A and PWM were respectively assessed following exposure to 60 Co gamma rays by 3 H-thymidine uptake and hydroxylapatite chromatography. It was showed the transformation of lymphocytes stimulated with PHA, Con A and PWM were suppressed by gamma rays and the dose-effect curves were biphase within the range of 0∼8 Gy. The lymphocytes stimulated with PWM was the most resistant to gamma rays. The extent of DNA strand breaks in lymphocytes induced by gamma rays was linearly related to the dose within the range of 0∼30 Gy and was identical in three kinds of lymphocytes. After post-irradiation incubation of 37 deg C, the DNA strand breaks could be repaired incompletely and after maxium repair the strand breaks were observed again. The repair ratio of strand breaks in the lymphocytes stimulated with PWM was the highest in the cells with three mitogens. The results showed that the difference of radiation effect on the transformation is probably related to the repair ability of DNA strand breaks

  7. Adaptive response induced by low concentrations of MMC in human peripheral lymphocytes

    Sun Shuqing; Wang Bin; Jiang Jie

    1998-01-01

    Samples of cultured human peripheral lymphocytes were pre-treated with mitomycin C (MMC) in concentrations of 0.01∼0.1 μg/mL at 34 h of incubation and then exposed to 1.5 Gy of X-rays. Chromosome aberrations, sister chromatid exchanges and micronuclei for these lymphocytes were observed. The results show that the chromosome aberration rates for lymphocytes pre-treated with MMC in concentrations of 0.5 and 0.075 μg/mL and the frequencies of sister chromatid exchanges for lymphocytes pre-treated with MMC in concentrations of 0.01 μg/mL were significantly lower than their own expected values but the rates of micronuclei for lymphocytes pre-treated with MMC in concentrations of 0.05, 0.075 and 0.1 μg/mL were significantly higher than the expected values. Such results suggest that for studying the cross resistance of lymphocytes to chemicals and ionizing radiation, inconsistent conclusions may be obtained if different endpoints are based on

  8. Age-dependent effects of He-Ne laser irradiation on the membrane fluidity of human erythrocytes

    Kovacs, Eugenia; Savopol, Tudor; Pologea-Moraru, Roxana; Makropoulou, Mersini I.; Serafetinides, Alexander A.

    1997-12-01

    The low power He-Ne laser radiation has been extensively used in past decades as medical device to relieve pain, accelerate wound healing as well as aiming beam in invisible laser beam in invisible laser beam applications. It is not known however if there are any secondary, undesirable effects of He-Ne laser radiation on the irradiated tissue. In this paper we investigate the changes induced in membrane fluidity of human erythrocyte during/upon the interaction with the He-Ne laser beam having the parameters currently used for target aiming in laser surgery.

  9. A murine model of falciparum-malaria by in vivo selection of competent strains in non-myelodepleted mice engrafted with human erythrocytes.

    Iñigo Angulo-Barturen

    Full Text Available To counter the global threat caused by Plasmodium falciparum malaria, new drugs and vaccines are urgently needed. However, there are no practical animal models because P. falciparum infects human erythrocytes almost exclusively. Here we describe a reliable falciparum murine model of malaria by generating strains of P. falciparum in vivo that can infect immunodeficient mice engrafted with human erythrocytes. We infected NOD(scid/beta2m-/- mice engrafted with human erythrocytes with P. falciparum obtained from in vitro cultures. After apparent clearance, we obtained isolates of P. falciparum able to grow in peripheral blood of engrafted NOD(scid/beta2m-/- mice. Of the isolates obtained, we expanded in vivo and established the isolate Pf3D7(0087/N9 as a reference strain for model development. Pf3D7(0087/N9 caused productive persistent infections in 100% of engrafted mice infected intravenously. The infection caused a relative anemia due to selective elimination of human erythrocytes by a mechanism dependent on parasite density in peripheral blood. Using this model, we implemented and validated a reproducible assay of antimalarial activity useful for drug discovery. Thus, our results demonstrate that P. falciparum contains clones able to grow reproducibly in mice engrafted with human erythrocytes without the use of myeloablative methods.

  10. Expression of Plasmodium falciparum erythrocyte membrane protein 1 in experimentally infected humans

    Lavstsen, Thomas; Magistrado, Pamela; Hermsen, Cornelus C

    2005-01-01

    -encoded Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1) family, which is expressed on the surface of infected erythrocytes where it mediates binding to endothelial receptors. Thus, severe malaria may be caused by parasites expressing PfEMP1 variants that afford parasites optimal sequestration...... in immunologically naive individuals and high effective multiplication rates. METHODS: var gene transcription was analysed using real time PCR and PfEMP1 expression by western blots as well as immune plasma recognition of parasite cultures established from non-immune volunteers shortly after infection with NF54...... compared to parasites expressing other var genes. The differential expression of PfEMP1 was confirmed at the protein level by immunoblot analysis. In addition, serological typing showed that immune sera more often recognized second and third generation parasites than first generation parasites. CONCLUSION...

  11. Pharmacologic manipulation of human erythrocyte 2,3-diphosphoglycerate levels by prednisone administration.

    Silken, A B

    1975-02-01

    Erythrocyte 2,3-diphosphoglycerate (2,3-DPG) concentrations in 10 patients with acute lymphoblastic leukemia rose 21.3%(P smaller than 0.02) after 3 weeks of prednisone and vincristine therapy, and returned to pretreatment level 2 weeks after therapy had been discontinued. The mean 2,3-DPG level of three patients on vincristine alone did not vary significantly from the control level of the leukemia patients on prednisone and vincristine. No significant change in serum inorganic phosphate level was observed. The mean erythrocyte 2,3-DPG concentration of 17 nephrotic syndrome patients being treated with chronic prednisone therapy was 14.0% higher than a control group of 20 nephrotic syndrome patients not being treated with prednisone (P small than 0.01). A significant positive correlation was observed between the dose of prednisone and 2,3-DPG level.

  12. Investigations into the binding of 125I-calmodulin to CA++ transport ATPase of human erythrocytes

    Sterk, V.

    1983-01-01

    The study described was carried out in order to investigate the binding of 125 I-calmodulin to Ca ++ transport ATPase using different Ca ++ concentrations and temperatures. The data obtained from these experiments were subsequently analysed in such as a way as to yield meaningful information relating to the mechanisms underlying the attachment of calmodulin to Ca ++ transport ATPase, the % proportion of membrane protein that was attributable to the enzyme as well as the number of calmodulin receptor sites on the individual erythrocytes, etc. Comparisons with data from the relevant literature permitted conclusions to be drawn concerning the mode of Ca ++ transport at the level of the erythrocytes. A new methodology and processing technique had to be developed prior to the beginning of the experiments. (orig./MG) [de

  13. Immunomodulatory effects of Bacteroides products on in vitro human lymphocyte functions.

    Shenker, B J; Slots, J

    1989-03-01

    Bacteroides spp. have been implicated in the pathogenesis of several diseases, including periodontal diseases. In this study sonic extracts of 6 Bacteroides spp. were examined for their abilities to alter human lymphocyte function. We found that soluble extracts from Bacteroides intermedius, Bacteroides endodontalis, Bacteroides asaccharolyticus, Bacteroides melaninogenicus, and to a lesser degree Bacteroides loescheii, caused dose-dependent inhibition of human lymphocyte responsiveness to both mitogens and antigens. Suppression involved altered DNA, RNA and protein synthesis as well as immunoglobulin production. In contrast, Bacteroides gingivalis did not suppress these responses; instead, it stimulated lymphocyte proliferation and enhanced immunoglobulin production. It has been proposed that impaired host defense may play a pivotal role in the pathogenesis of many infections. The data presented in this paper suggest that microbial mediated immunosuppression may conceivably alter the nature and consequences of host-parasite interactions in periodontal disease.

  14. Annotating N termini for the human proteome project: N termini and Nα-acetylation status differentiate stable cleaved protein species from degradation remnants in the human erythrocyte proteome.

    Lange, Philipp F; Huesgen, Pitter F; Nguyen, Karen; Overall, Christopher M

    2014-04-04

    A goal of the Chromosome-centric Human Proteome Project is to identify all human protein species. With 3844 proteins annotated as "missing", this is challenging. Moreover, proteolytic processing generates new protein species with characteristic neo-N termini that are frequently accompanied by altered half-lives, function, interactions, and location. Enucleated and largely void of internal membranes and organelles, erythrocytes are simple yet proteomically challenging cells due to the high hemoglobin content and wide dynamic range of protein concentrations that impedes protein identification. Using the N-terminomics procedure TAILS, we identified 1369 human erythrocyte natural and neo-N-termini and 1234 proteins. Multiple semitryptic N-terminal peptides exhibited improved mass spectrometric identification properties versus the intact tryptic peptide enabling identification of 281 novel erythrocyte proteins and six missing proteins identified for the first time in the human proteome. With an improved bioinformatics workflow, we developed a new classification system and the Terminus Cluster Score. Thereby we described a new stabilizing N-end rule for processed protein termini, which discriminates novel protein species from degradation remnants, and identified protein domain hot spots susceptible to cleavage. Strikingly, 68% of the N-termini were within genome-encoded protein sequences, revealing alternative translation initiation sites, pervasive endoproteolytic processing, and stabilization of protein fragments in vivo. The mass spectrometry proteomics data have been deposited to ProteomeXchange with the data set identifier .

  15. Effect of Lidocaine and Epinephrine on Human Erythrocyte Shape and Vesiculability of Blood Cells

    Tanja Slokar

    2015-01-01

    Full Text Available The effect of local anesthetic composed of lidocaine and epinephrine on vesiculability of blood cells and erythrocyte shape was studied. Whole blood and plasma were incubated with lidocaine/epinephrine. Extracellular vesicles were isolated by centrifugation and washing and counted by flow cytometry. Lidocaine/epinephrine and each component alone were added to diluted blood. Shape changes were recorded by micrographs. An ensemble of captured frames was analyzed for populations of discocytes, echinocytes, and stomatocytes by using statistical methods. Incubation of whole blood and blood plasma with lidocaine/epinephrine considerably increased concentration of extracellular vesicles in isolates (for an average factor 3.4 in blood and 2.8 in plasma. Lidocaine/epinephrine caused change of erythrocyte shape from mainly discocytic to mainly stomatocytic (higher than 50%. Lidocaine alone had even stronger stomatocytic effect (the percent of stomatocytes was higher than 95% while epinephrine had echinocytic effect (the percent of echinocytes was higher than 80%. The differences were highly statistically significant p<10-8 with statistical power P=1. Lidocaine/epinephrine induced regions of highly anisotropically curved regions indicating that lidocaine and epinephrine interact with erythrocyte membrane. It was concluded that lidocaine/epinephrine interacts with cell membranes and increases vesiculability of blood cells in vitro.

  16. Human thiopurine methyltransferase pharmacogenetics: effect of phenotype on sensitivity of cultured lymphocytes to 6-mercaptopurine

    Van Loon, J.; Weinshilboum, R.

    1986-01-01

    Thiopurine methyltransferase (EC 2.1.1.67, TPMT) catalyzes the S-methylation of thiopurine drugs such as 6-mercaptopurine (6-MP). TPMT activity in human lymphocytes and other tissues is controlled by a common genetic polymorphism. These experiments were designed to study the relationship between TPMT phenotype and the effect of 6-MP on 3 H-thymidine ( 3 H-TdR) incorporation into phytohemaglutinin (PHA) stimulated human peripheral blood lymphocytes. Lymphocytes were obtained from the blood of nine subjects, three subjects with each TPMT phenotype. 6-MP dose response curves were performed at optimal (10 μg/ml) and suboptimal (1 μg/ml) concentrations of PHA. ED50 values for 6-MP with lymphocytes from subjects who genetically lacked TPMT activity were higher than ED50 values for lymphocytes from subjects with genetically intermediate or high TPMT activity. However, ED50 values decreased as level of stimulation increased. Therefore, the effects of 6-MP were studied at a series of PHA concentrations that ranged from 0.1 μg/ml to 10 μg/ml. Lymphocytes from subjects who lacked TPMT activity had significantly higher K/sub ii/ values (1.37 +/- 0.340 μM; mean +/- SEM) for inhibition of 3 H-TdR incorporation by 6-MP than did lymphocytes from subjects with intermediate or high TPMT activity (0.529 +/- 0.068 μM and 0.327 +/- 0.064 μM, respectively, P < .05 for both comparisons)

  17. Human thiopurine methyltransferase pharmacogenetics: effect of phenotype on sensitivity of cultured lymphocytes to 6-mercaptopurine

    Van Loon, J.; Weinshilboum, R.

    1986-03-05

    Thiopurine methyltransferase (EC 2.1.1.67, TPMT) catalyzes the S-methylation of thiopurine drugs such as 6-mercaptopurine (6-MP). TPMT activity in human lymphocytes and other tissues is controlled by a common genetic polymorphism. These experiments were designed to study the relationship between TPMT phenotype and the effect of 6-MP on /sup 3/H-thymidine (/sup 3/H-TdR) incorporation into phytohemaglutinin (PHA) stimulated human peripheral blood lymphocytes. Lymphocytes were obtained from the blood of nine subjects, three subjects with each TPMT phenotype. 6-MP dose response curves were performed at optimal (10 ..mu..g/ml) and suboptimal (1 ..mu..g/ml) concentrations of PHA. ED50 values for 6-MP with lymphocytes from subjects who genetically lacked TPMT activity were higher than ED50 values for lymphocytes from subjects with genetically intermediate or high TPMT activity. However, ED50 values decreased as level of stimulation increased. Therefore, the effects of 6-MP were studied at a series of PHA concentrations that ranged from 0.1 ..mu..g/ml to 10 ..mu..g/ml. Lymphocytes from subjects who lacked TPMT activity had significantly higher K/sub ii/ values (1.37 +/- 0.340 ..mu..M; mean +/- SEM) for inhibition of /sup 3/H-TdR incorporation by 6-MP than did lymphocytes from subjects with intermediate or high TPMT activity (0.529 +/- 0.068 ..mu..M and 0.327 +/- 0.064 ..mu..M, respectively, P < .05 for both comparisons).

  18. DNA-protein crosslinks in peripheral lymphocytes of individuals exposed to hexavalent chromium compounds.

    Zhitkovich, A; Lukanova, A; Popov, T; Taioli, E; Cohen, H; Costa, M; Toniolo, P

    1996-01-01

    Abstract DNA-protein crosslinks were measured in peripheral blood lymphocytes of chrome-platers and controls from Bulgaria in order to evaluate a genotoxic effect of human exposure to carcinogenic Cr(VI) compounds. Chrome-platers and most of the unexposed controls were from the industrial city of Jambol; some additional controls were recruited from the seaside town of Burgas. The chrome-platers had significantly elevated levels of chromium in pre- and post-shift urine, erythrocytes and lymphocytes compared with the control subjects. The largest differences between the two groups were found in erythrocyte chromium concentrations which are considered to be indicative of Cr(VI) exposure. Despite the significant differences in internal chromium doses, levels of DNA-protein crosslinks were not significantly different between the combined controls and exposed workers. Individual DNA-protein crosslinks, however, correlated strongly with chromium in erythrocytes at low and moderate doses but at high exposures, such as among the majority of chrome-platers, these DNA adducts were saturated at maximum levels. The saturation of DNA-protein crosslinks seems to occur at 7-8 μg I-(1) chromium in erythrocytes whereas a mean erythrocyte chromium among the chrome platers was as high as 22.8 μg l(-1). Occupationally unexposed subjects exhibited a significant variability with respect to the erythrocyte chromium concentration, however erythrocyte chromium levels correlated closely with DNA-protein crosslinks in lymphocytes. The controls from Jambol had higher chromium concentrations in erythrocytes and elevated levels of DNA-protein crosslinks compared with Burgas controls. Occupational exposure to formaldehyde among furniture factory workers did not change levels of DNA-protein crosslinks in peripheral lymphocytes. DNA-protein crosslink measurements showed a low intraindividual variability and their levels among both controls and exposed indivduals were not affected by smoking, age

  19. Diphtheria toxin resistance in human lymphocytes and lymphoblasts in the in vivo somatic cell mutation test

    Tomkins, D.J.; Wei, L.; Laurie, K.E.

    1985-01-01

    It has been shown that circulating peripheral blood lymphocytes can be used for the enumeration of 6-thioguanine-resistant cells that presumably arise by mutation in vivo. This somatic cell mutation test has been studied in lymphocytes from human populations exposed to known mutagens and/or carcinogens. The sensitivity of the test could be further enhanced by including other gene markers, since there is evidence for locus-specific differences in response to mutagens. Resistance to diphtheria toxin (Dip/sup r/) seemed like a potential marker to incorporate into the test because the mutation acts codominantly, can readily be selected in human diploid fibroblasts and Chinese hamster cells with no evidence for cell density or cross-feeding effects, and can be assayed for in nondividing cells by measuring protein synthesis inhibition. Blood samples were collected from seven individuals, and fresh, cryopreserved, or Epstein-Barr virus (EBV)-transformed lymphocytes were tested for continued DNA synthesis ( 3 H-thymidine, autoradiography) or protein synthesis ( 35 S-methionine, scintillation counting). Both fresh and cryopreserved lymphocytes, stimulated to divide with phytohemagglutinin (PHA), continued to synthesize DNA in the presence of high doses of diphtheria toxin (DT). Similarly, both dividing (PHA-stimulated) and nondividing fresh lymphocytes carried on significant levels of protein synthesis even 68 hr after exposure to 100 flocculating units (LF)/ml DT. The results suggest that human T and B lymphocytes may not be as sensitive to DT protein synthesis inhibition as human fibroblast and Chinese hamster cells. For this reason, Dip/sup r/ may not be a suitable marker for the somatic cell mutation test

  20. Study of the radioprotective effect of flavonoid quercetin on human lymphocytes

    Siqueira, Williams Nascimento de

    2013-01-01

    Ionizing radiation has been used in various fields of study, as medicine, industry, energy production, surgical materials sterilization, preservation and sterilization of foods, among others. These radiations may be responsible for adverse effects at molecular level in living organisms, where most important damage occurs in deoxyribonucleic acid molecule, DNA. These harmful effects caused by radiation highlights the importance of acquiring knowledge about radioprotector substances because they can act as protector of living tissue of those effects. In this research was investigated the possible radioprotective effect 'in vitro' of the flavonoid quercetin in human lymphocytes exposed to gamma radiation. At first, test was performed to evaluate the antioxidant activity of quercetin by capturing DPPH free radical molecules. Then, it was collected peripheral blood of volunteers donors. Then the samples were irradiated from linear accelerator (Siemens Primus - energy of 6 MeV and dose rate of 200 cGy/min from IMIP-PE). After samples irradiation, lymphocytes were isolated from whole blood and then the culture was carried out to obtain lymphocyte in metaphases and subsequent, analysis of chromosomal abnormalities were done at optical microscope. Statistical analysis was used Student 't' test. The results showed that quercetin at a concentration of 37.5 μM presented radioprotective against damage from gamma radiation on human lymphocytes in vitro. Have been also observed that the irradiated lymphocytes showed morphologically unchanged after undergoing the presence of the flavonoid quercetin. (author)

  1. Intracellular calcium mobilization in human lymphocytes in the presence of synthetic IgG Fc peptides

    Plummer, J.M.; Panahi, Y.P.; McClurg, M.R.; Hahn, G.S.; Naemura, J.R.

    1986-01-01

    Certain synthetic peptides derived from the Fc region of human IgG can suppress the mixed lymphocyte response. These peptides were tested for the ability to induce intracellular calcium mobilization in human lymphocytes using fura-2/calcium fluorescence. T cells were isolated by rosetting and were > 90% OKT3 positive. Lymphocytes were incubated with the acetoxymethyl ester of fura-2 (10 μM) for 60 minutes at 37 0 C. Fluorescence intensity changes at 505 nm were monitored at an excitation lambda of 340 nm. Fura-2 was not cytotoxic compared to quin-2 since fura-2 loaded mononuclear cells incorporated 3 H-thymidine when stimulated by PHA, succinyl Con A, PWM or LPS-STM whereas quin-2 loaded cells showed a dose dependent inhibition of proliferation. Those synthetic peptides (5 to 400 μg/ml) that suppressed the MLR induced a dose dependent increase in intracellular calcium in mononuclear cells, lymphocytes, non-T cells and T cells. The fura-2 calcium fluorescence time course response was similar for peptide, PHA and succinyl Con A. These results suggest that these immunoregulatory peptides suppress 3 H-thymidine incorporation at a point after intracellular calcium mobilization and that fura-2 has advantages over quin-2 in measuring intracellular calcium levels in lymphocytes

  2. Manifestation of radiaton injury of human lymphocytes using PHA mitogenic stimulation in different culture systems

    Horky, J.

    1986-01-01

    The proliferative response of human lymphocytes to phytohemagglutinin in vitro is affected by X-irradiation. Dose-related changes in mitogenic stimulation of irradiated lymphocytes were compared for two culture systems - the cultivation of separated lymphocytes and the cultivation of whole blood. In the whole blood cultures, the proliferative activity of stimulated lyphocytes was markedly and reproducibly depressed by irradiation. An exponential curve could be fitted to the values of mitogenic response within a dose range from 0 to 2.5 Gy with high correlation. In a modified test where the mitogenic stimulus was given after a 24 h delay, depression in the response was even more pronounced. Radiosensitivity of human lymphocytes as determined by means of mitogenic stimulation in the whole blood cultures appears to be a characteristic individual feature. The mean D 37 value of the radiation-induced depression in mitogenic response in a group of 20 healthy donors was 2.5 Gy in the standard test and 2.0 Gy in the test with a delayed mitogenic stimulus. In contrast, the data obtained from separated lymphocyte cultures were characterized by a high degree of test-to-test variability and by much lower radiosensitivity. The possible mechanisms of these distinctive manifestations of the same primary radiation injury are discussed. (author) 3 tabs., 2 figs., 12 refs

  3. Inorganic arsenic represses interleukin-17A expression in human activated Th17 lymphocytes

    Morzadec, Claudie; Macoch, Mélinda; Robineau, Marc; Sparfel, Lydie [UMR INSERM U1085, Institut de Recherche sur la Santé, l' Environnement et le Travail (IRSET), Université de Rennes 1, 2 avenue du Professeur Léon Bernard, 35043 Rennes (France); Fardel, Olivier [UMR INSERM U1085, Institut de Recherche sur la Santé, l' Environnement et le Travail (IRSET), Université de Rennes 1, 2 avenue du Professeur Léon Bernard, 35043 Rennes (France); Pôle Biologie, Centre Hospitalier Universitaire (CHU) Rennes, 2 rue Henri Le Guilloux, 35033 Rennes (France); Vernhet, Laurent, E-mail: laurent.vernhet@univ-rennes1.fr [UMR INSERM U1085, Institut de Recherche sur la Santé, l' Environnement et le Travail (IRSET), Université de Rennes 1, 2 avenue du Professeur Léon Bernard, 35043 Rennes (France)

    2012-08-01

    Trivalent inorganic arsenic [As(III)] is an efficient anticancer agent used to treat patients suffering from acute promyelocytic leukemia. Recently, experimental studies have clearly demonstrated that this metalloid can also cure lymphoproliferative and/or pro-inflammatory syndromes in different murine models of chronic immune-mediated diseases. T helper (Th) 1 and Th17 lymphocytes play a central role in development of these diseases, in mice and humans, especially by secreting the potent pro-inflammatory cytokine interferon-γ and IL-17A, respectively. As(III) impairs basic functions of human T cells but its ability to modulate secretion of pro-inflammatory cytokines by differentiated Th lymphocytes is unknown. In the present study, we demonstrate that As(III), used at concentrations clinically achievable in plasma of patients, has no effect on the secretion of interferon-γ from Th1 cells but almost totally blocks the expression and the release of IL-17A from human Th17 lymphocytes co-stimulated for five days with anti-CD3 and anti-CD28 antibodies, in the presence of differentiating cytokines. In addition, As(III) specifically reduces mRNA levels of the retinoic-related orphan receptor (ROR)C gene which encodes RORγt, a key transcription factor controlling optimal IL-17 expression in fully differentiated Th17 cells. The metalloid also blocks initial expression of IL-17 gene induced by the co-stimulation, probably in part by impairing activation of the JNK/c-Jun pathway. In conclusion, our results demonstrate that As(III) represses expression of the major pro-inflammatory cytokine IL-17A produced by human Th17 lymphocytes, thus strengthening the idea that As(III) may be useful to treat inflammatory immune-mediated diseases in humans. -- Highlights: ► Arsenic inhibits secretion of IL-17A from human naïve and memory Th17 lymphocytes. ► Arsenic represses early expression of IL-17A gene in human activated T lymphocytes. ► Arsenic interferes with activation of

  4. Antioxidant capacity and radical scavenging effect of polyphenol rich Mallotus philippenensis fruit extract on human erythrocytes: an in vitro study.

    Gangwar, Mayank; Gautam, Manish Kumar; Sharma, Amit Kumar; Tripathi, Yamini B; Goel, R K; Nath, Gopal

    2014-01-01

    Mallotus philippinensis is an important source of molecules with strong antioxidant activity widely used medicinal plant. Previous studies have highlighted their anticestodal, antibacterial, wound healing activities, and so forth. So, present investigation was designed to evaluate the total antioxidant activity and radical scavenging effect of 50% ethanol fruit glandular hair extract (MPE) and its role on Human Erythrocytes. MPE was tested for phytochemical test followed by its HPLC analysis. Standard antioxidant assays like DPPH, ABTS, hydroxyl, superoxide radical, nitric oxide, and lipid peroxidation assay were determined along with total phenolic and flavonoids content. Results showed that MPE contains the presence of various phytochemicals, with high total phenolic and flavonoid content. HPLC analysis showed the presence of rottlerin, a polyphenolic compound in a very rich quantity. MPE exhibits significant strong scavenging activity on DPPH and ABTS assay. Reducing power showed dose dependent increase in concentration absorption compared to standard, Quercetin. Superoxide, hydroxyl radical, lipid peroxidation, nitric oxide assay showed a comparable scavenging activity compared to its standard. Our finding further provides evidence that Mallotus fruit extract is a potential natural source of antioxidants which have a protective role on human Erythrocytes exhibiting minimum hemolytic activity and this justified its uses in folklore medicines.

  5. Piracetam and TRH analogues antagonise inhibition by barbiturates, diazepam, melatonin and galanin of human erythrocyte D-glucose transport

    Naftalin, Richard J; Cunningham, Philip; Afzal-Ahmed, Iram

    2004-01-01

    Nootropic drugs increase glucose uptake into anaesthetised brain and into Alzheimer's diseased brain. Thyrotropin-releasing hormone, TRH, which has a chemical structure similar to nootropics increases cerebellar uptake of glucose in murine rolling ataxia. This paper shows that nootropic drugs like piracetam (2-oxo 1 pyrrolidine acetamide) and levetiracetam and neuropeptides like TRH antagonise the inhibition of glucose transport by barbiturates, diazepam, melatonin and endogenous neuropeptide galanin in human erythrocytes in vitro. The potencies of nootropic drugs in opposing scopolamine-induced memory loss correlate with their potencies in antagonising pentobarbital inhibition of erythrocyte glucose transport in vitro (Pnootropics, D-levetiracetam and D-pyroglutamate, have higher antagonist Ki's against pentobarbital inhibition of glucose transport than more potent L-stereoisomers (Pnootropics, like aniracetam and levetiracetam, while antagonising pentobarbital action, also inhibit glucose transport. Analeptics like bemigride and methamphetamine are more potent inhibitors of glucose transport than antagonists of hypnotic action on glucose transport. There are similarities between amino-acid sequences in human glucose transport protein isoform 1 (GLUT1) and the benzodiazepine-binding domains of GABAA (gamma amino butyric acid) receptor subunits. Mapped on a 3D template of GLUT1, these homologies suggest that the site of diazepam and piracetam interaction is a pocket outside the central hydrophilic pore region. Nootropic pyrrolidone antagonism of hypnotic drug inhibition of glucose transport in vitro may be an analogue of TRH antagonism of galanin-induced narcosis. PMID:15148255

  6. Comparison between cytogenetic damage induced in human lymphocytes by environmental chemicals or radiation

    Cebulska-Wasilewska, A. [Institute of Nuclear Physics, Cracow (Poland)

    1997-12-31

    Author compared cytogenetic effects of chemicals (benzene and the member at benzene related compounds) and ionizing radiation on the human lymphocytes. Levels of various types of cytogenetic damage observed among people from petroleum plants workers groups are similar to the levels of damages detected in the blood of people suspected of the accidental exposure to a radiation source

  7. Comparison between cytogenetic damage induced in human lymphocytes by environmental chemicals or radiation

    Cebulska-Wasilewska, A.

    1997-01-01

    Author compared cytogenetic effects of chemicals (benzene and the member at benzene related compounds) and ionizing radiation on the human lymphocytes. Levels of various types of cytogenetic damage observed among people from petroleum plants workers groups are similar to the levels of damages detected in the blood of people suspected of the accidental exposure to a radiation source

  8. A comparative study of radioprotective effect of several antioxidants on human blood lymphocytes

    Wang Mingsuo; Zhu Gengbai; Gu Xuandi

    1992-01-01

    By means of improved fluorometric method with 2-thiobarbituric acid (TBA) as the fluorometric agent, radioprotective effects of four kinds of antioxidants on 60 Co γ-ray induced lipid peroxidation (LPO) level, i.e. Malondialdehyde (MDA) content changes in human blood lymphocytes were in human blood lymphocytes were compared by using relative protective efficiency (RPE) as an indicator. The LPO level in human lymphocytes which had been treated with an antioxidant at an concentration of 5 x 10 -3 g/L for 1 hr was measured 2 hr after exposure to 4 Gy of γ-rays, and the RPE values of antioxidants were calculated under these conditions: SOD, 38.23; VE, 23.75:VC, 19.32 and Se +4 , 18.27, thus the anticipation that the compounds, superoxide dismutase (SOD), 2-tocopherols (VE), ascorbic acid (VC) and Na 2 SeO 3 (Se +4 ) had radioprotective effects was confirmed. It was found that the radioprotective beneficial sequences of four kinds of antioxidants were arranged as SOD>VE>VC,Se +4 . The results show that radioprotective effects of exogenous antioxidants on radiation induced LPO damage are dependent not only on irradiation dosage, but also especially on property of antioxidants, drug concentration, pretreatment and monitoring time, etc. The mechanism of these antioxidants effecting as radioprotectants on human lymphocytes is discussed in connection with LPO damage and radioprotection

  9. Post-irradiation treatment of human lymphocytes with spermidine reduced frequency of chromatid breaks

    Bocian, E.; Rosiek, O.; Ziemba-Zoltowska, B.

    1978-01-01

    Human lymphocyte cultures were X-irradiated with a single dose of 100 or 200 rad 46 h after phytohemagglutinin stimulation. In dose-fractionation experiments, 2h later the second dose was applied. All the cultures were harvested at 54 h after their initiation. In lymphocytes irradiated with a single dose of 200 rad, 2h post-irradiation contact with 10 -5 M exogeneous spermidine resulted in reduction of chromatid breaks by 34 %. Introduction of spermidine into culture medium for fractionation interval between the 2 doses of 100 rad reduced the frequency of chromatid breaks by 42 %. (author)

  10. Application of a new ultra-microculture system. II. Stimulation of human B lymphocytes.

    Ulmer, A J; Gruber, M; Flad, H D

    1988-07-22

    An ultra-microtechnique for culturing human B-lymphocytes in glass capillary tubes using a volume of 2 microliter is described. The advantage of this ultra-microculture system is that only a small number of lymphocytes and minute amounts of culture medium (or test factors) are required. Optimal culture conditions for the formation of Ig-secreting plaque-forming cells (PFC) after stimulation of mononuclear cells with pokeweed mitogen are given. Furthermore it is shown that immunoglobulin secreted into culture supernatants by purified B cells in the presence of T cell subsets can be measured in a microELISA.

  11. Behavior of the nucleic acid ethidium complex sedimentation of human lymphocytes after gamma irradiation

    Langrock, K.

    1982-01-01

    Under standardized conditions the repair kinetic test by Fender and Hartwig demonstrates the dose dependence of the injury of the nucleic acid complex of human lymphocytes after gamma irradiation and their repair even in low dose regions. Seasonal changes with infect incubation, individual variability in the lymphocyte population and culture conditions are to be proved before clinical application of the test in radiotherapy to generalize the influence of the factors. 3.4 up to 6 μg/ml ethidium bromide should be chosen as an optimum ethidium concentration of the gradient. (author)

  12. Predominant CD4 T-lymphocyte tropism of human herpesvirus 6-related virus.

    Takahashi, K; Sonoda, S; Higashi, K; Kondo, T; Takahashi, H; Takahashi, M; Yamanishi, K

    1989-01-01

    Human herpesvirus 6 (HHV-6)-related virus was isolated from CD4+ CD8- and CD3+ CD4+ mature T lymphocytes but could not be isolated from CD4- CD8+, CD4- CD8-, and CD3- T cells in the peripheral blood of exanthem subitum patients. HHV-6-related virus predominantly infected CD4+ CD8+, CD4+ CD8-, and CD3+ CD4+ cells with mature phenotypes and rarely infected CD4- CD8+ cells from cord blood mononuclear cells, which suggested predominant CD4 mature T-lymphocyte tropism of HHV-6-related virus.

  13. Effect of radiation therapy on the mitogenic response of in vitro irradiated human lymphocytes to phytohaemagglutinin

    Baral, E.; Blomgren, H.; Einhorn, N.; Lax, I.; Juhlin, I.

    1977-01-01

    Irradiation of human peripheral lymphocytes in vitro reduces their capacity to be triggered to DNA-synthesis by PHA in a two-dose shaped fashion suggesting the presence of one relatively radiationsensitive and one relatively resistant cell population. Intracavitary and external radiation therapy for carcinoma of the uterus and vagina, which reduced the lymphocyte counts by approximately 66 per cent, did not significantly change the ratio of these subpopulations, indicating that PHA-reactive cells cannot be grouped into radiation sensitive and resistant subpopulations

  14. Apolipoprotein M mediates sphingosine-1-phosphate efflux from erythrocytes

    Christensen, Pernille M.; Bosteen, Markus H.; Hajny, Stefan

    2017-01-01

    Sphingosine-1-phosphate (S1P) is a bioactive lipid implicated in e.g. angiogenesis, lymphocyte trafficking, and endothelial barrier function. Erythrocytes are a main source of plasma S1P together with platelets and endothelial cells. Apolipoprotein M (apoM) in HDL carries 70% of plasma S1P, whereas...... 30% is carried by albumin. The current aim was to investigate the role of apoM in export of S1P from human erythrocytes. Erythrocytes exported S1P more efficiently to HDL than to albumin, particularly when apoM was present in HDL. In contrast, export of sphingosine to HDL was unaffected...... by the presence of apoM. The specific ability of apoM to promote export of S1P was independent of apoM being bound in HDL particles. Treatment with MK-571, an inhibitor of the ABCC1 transporter, effectively reduced export of S1P from human erythrocytes to apoM, whereas the export was unaffected by inhibitors...

  15. Protective Effect of Curcumin on γ - radiation Induced Chromosome Aberrations in Human Blood Lymphocytes

    AlSuhaibani, E.S

    2008-01-01

    The present work is aimed at evaluating the radioprotective effect of curcumin on γ radiation induced genetic toxicity. The DNA damage was analyzed by the frequencies of chromosome aberrations assay. Human lymphocytes were treated in vitro with 5.0 γg/ml of curcumin for 30 min at 37 degree C then exposed to 1, 2 and 4 Gy gamma-radiation. The lymphocytes which were pre-treated with curcumin exhibited a significant decrease in the frequency of chromosome aberration at 1 and 2 Gy radiation-induced chromosome damage as compared with the irradiated cells which did not receive the curcumin pretreatment. Thus, pretreatment with curcumin gives protection to lymphocytes against γ-radiation induced chromosome aberration at certain doses. (author)

  16. Pyrimethamine-induced alterations in human lymphocytes in vitro. Mechanisms and reversal of the effect

    Bygbjerg, Ib Christian

    1985-01-01

    It has previously been shown that the antiprotozoal drug pyrimethamine (PYR) in concentrations corresponding to those obtained in clinical practice temporarily suppressed the proliferation of phytohaemagglutinin (PHA-) stimulated human lymphocytes in vitro; 10-fold higher concentrations permanently...... suppressed PHA-stimulated cells, as indicated by decreased numbers of cells and DNA synthesis. In the present study, it was found that the 3H-deoxyuridine incorporation in PHA-stimulated lymphocytes was suppressed by PYR, and that PYR caused defective deoxyuridine suppression of 14C-thymidine incorporation......, reduced thymidylate synthesis cannot be the sole consequence of PYR exposure. It is suggested that an additional folate-dependent factor plays an important role in the antimitotic activity of PYR on lymphocytes....

  17. Drinking beer reduces radiation-induced chromosome aberrations in human lymphocytes

    Monobe, Manami

    2002-01-01

    We here investigated and reported the effects of beer drinking on radiation-induced chromosome aberrations in blood lymphocytes. Human blood that was collected either before or after drinking a 700 ml beer was in vitro irradiated with 200 kVp X rays or 50 keV/μm carbon ions. The relation between the radiation dose and the aberration frequencies (fragments and dicentrics) was significantly (P<0.05) lower for lymphocytes collected 3 h after beer drinking than those before drinking. Fitting the dose response to a linear quadratic model showed that the alpha term of carbon ions was significantly (P<0.05) decreased by beer drinking. A decrease of dicentric formation was detected as early as 0.5 h after beer drinking, and lasted not shorter than 4.5 h. The mitotic index of lymphocytes was higher after beer drinking than before, indicating that a division delay would not be responsible for the low aberrations induced by beer drinking. An in vitro treatment of normal lymphocytes with 0.1 M ethanol, which corresponded to a concentration of 6-times higher than the maximum ethanol concentration in the blood after beer drinking, reduced the dicentric formation caused by X-ray irradiation, but not by carbon-ion irradiation. The beer-induced reduction of dicentric formation was not affected by serum. It is concluded that beer could contain non-ethanol elements that reduce the chromosome damage of lymphocytes induced by high-LET radiation. (author)

  18. Epigallocatechin-3-Gallate Protects Erythrocyte Ca2+-ATPase and Na+/K+-ATPase Against Oxidative Induced Damage During Aging in Humans

    Prabhanshu Kumar

    2014-10-01

    Full Text Available Purpose: The main purpose of this study was to investigate the protective role of epigallocatechin-3-gallate on tertiary butyl hydroperoxide induced oxidative damage in erythrocyte during aging in humans. Methods: Human erythrocyte membrane bound Ca2+-ATPase and Na+/K+-ATPase activities were determined as a function of human age. Protective role of epigallocatechin-3-gallate was evaluated by in vitro experiments by adding epigallocatechin-3-gallate in concentration dependent manner (final concentration range 10-7M to 10-4M to the enzyme assay medium. Oxidative stress was induced in vitro by incubating washed erythrocyte ghosts with tertiary butyl hydroperoxide (10-5 M final concentration. Results: We have reported concentration dependent effect of epigallocatechin-3-gallate on tertiary butyl hydroperoxide induced damage on activities of Ca2+-ATPase and Na+/K+-ATPase during aging in humans. We have detected a significant (p < 0.001 decreased activity of Ca2+-ATPase and Na+/K+ -ATPase as a function of human age. Epigallocatechin-3-gallate protected ATPases against tertiary butyl hydroperoxide induced damage in concentration dependent manner during aging in humans. Conclusion: Epigallocatechin-3-gallate is a powerful antioxidant that is capable of protecting erythrocyte Ca2+-ATPase and Na+/K+ -ATPase against oxidative stress during aging in humans. We may propose hypothesis that a high intake of catechin rich diet may provide some protection against development of aging and age related diseases.

  19. L-cysteine efflux in erythrocytes as a function of human age: correlation with reduced glutathione and total anti-oxidant potential.

    Kumar, Prabhanshu; Maurya, Pawan Kumar

    2013-06-01

    Thiol compounds such as cysteine (Cys) and reduced glutathione (GSH) play an important role in human aging and age-related diseases. In erythrocytes, GSH is synthesized by glutamic acid, cysteine, and glycine, but the rate of GSH synthesis is determined only by the availability of L-cysteine. Cysteine supplementation has been shown to ameliorate several parameters that are known to degenerate during human aging. We have studied L-cysteine efflux in vitro in human erythrocytes as a function of age by suspending cells in solution containing 10 mM L-cysteine for uptake; later cells were re-suspended in phosphate-buffered saline (PBS)-glucose to allow efflux. Change in the free sulfhydryl (-SH) concentration was then measured to calculate the rate of efflux. The GSH/oxidized glutathione (GSSG) ratio was taken as a control to study the oxidation/reduction state of the erythrocyte. The total anti-oxidant potential of plasma was measured in terms of ferric reducing ability of plasma (FRAP) values. We have shown a significant (pL-cysteine in erythrocytes during human aging, and the GSH/GSSG ratio decreases as a function of human age. The decline in L-cysteine efflux during aging correlates with the decrease in GSH and the FRAP value. This finding may help to explain the shift in the redox status and low GSH concentration that might determine the rate of L-cysteine efflux observed in erythrocytes and an important factor in the development of oxidative stress in erythrocytes during aging.

  20. Retention of Plasmodium falciparum ring-infected erythrocytes in the slow, open microcirculation of the human spleen.

    Safeukui, Innocent; Correas, Jean-Michel; Brousse, Valentine; Hirt, Déborah; Deplaine, Guillaume; Mulé, Sébastien; Lesurtel, Mickael; Goasguen, Nicolas; Sauvanet, Alain; Couvelard, Anne; Kerneis, Sophie; Khun, Huot; Vigan-Womas, Inès; Ottone, Catherine; Molina, Thierry Jo; Tréluyer, Jean-Marc; Mercereau-Puijalon, Odile; Milon, Geneviève; David, Peter H; Buffet, Pierre A

    2008-09-15

    The current paradigm in Plasmodium falciparum malaria pathogenesis states that young, ring-infected erythrocytes (rings) circulate in peripheral blood and that mature stages are sequestered in the vasculature, avoiding clearance by the spleen. Through ex vivo perfusion of human spleens, we examined the interaction of this unique blood-filtering organ with P falciparum-infected erythrocytes. As predicted, mature stages were retained. However, more than 50% of rings were also retained and accumulated upstream from endothelial sinus wall slits of the open, slow red pulp microcirculation. Ten percent of rings were retained at each spleen passage, a rate matching the proportion of blood flowing through the slow circulatory compartment established in parallel using spleen contrast-enhanced ultrasonography in healthy volunteers. Rings displayed a mildly but significantly reduced elongation index, consistent with a retention process, due to their altered mechanical properties. This raises the new paradigm of a heterogeneous ring population, the less deformable subset being retained in the spleen, thereby reducing the parasite biomass that will sequester in vital organs, influencing the risk of severe complications, such as cerebral malaria or severe anemia. Cryptic ring retention uncovers a new role for the spleen in the control of parasite density, opening novel intervention opportunities.

  1. Benzo(a)pyrene activation and detoxification by human pulmonary alveolar macrophages and lymphocytes

    Marshall, M.V.; McLemore, T.L.; Martin, R.R.; Marshall, M.H.; Wray, N.P.; Busbee, D.L.; Cantrell, E.T.; Arnott, M.S.; Griffin, A.C.

    1980-01-01

    Comparisons of pulmonary alveolar macrophages and circulating lymphocytes from five smokers and five nonsmokers for their ability to metabolize benzo(a)pyrene as determined by high pressure liquid chromatography were carried out. Utilizing this approach, further investigation of activation and detoxification by several human cell types could provide the basis for more precise and comprehensive studies of carcinogen and drug metabolism in the human lung, and for a better assessment of cancer risk in selected populations

  2. Effects of Three Kinds of Curcuminoids on Anti-Oxidative System and Membrane Deformation of Human Peripheral Blood Erythrocytes in High Glucose Levels

    Wei Yang

    2015-01-01

    Full Text Available Background/Aims: Curcuminoids are the main bioactive constituents of the rhizome of turmeric. Erythrocytes lesions in diabetes are probably related to hyperglycemia and protein glycation. It has been reported that curcumin prevent lipid peroxidation. However, reports on the effects of demethoxycurcumin and bis-demethoxycurcumin on human erythrocytes at high glucose levels are scarce. Our aim is to investigate the effect of curcuminoids on oxidative stress and membrane of erythrocytes exposed to hyperglycemic condition. Methods: In this study, the different blood samples were treated with two doses of glucose (10 or 30 mM to mimic hyperglycemia in the presence or absence of three kinds of curcuminoids (5 or 10 μM in a medium at 37 °C for 24 h (Each experiment consists of 20 blood samples from 10 male and 10 female volunteers. The malondialdehyde was checked by HPLC, antioxidase (GSH and GSSG were measured by LC/MS, SOD was checked by WST-1 kit, morphology and phospholipid symmetry were detected by flow cytometry, confocal scanning microscope and scanning electron microscope. Results: The results illustrated that all three curcuminoids reduce oxidative stress damage on the membrane and maintain a better profile for erythrocytes. Furthermore, three curcuminoids had benefit effects on antioxidase. Conclusion: The three kinds of curcuminoids supplementation may prevent lipid peroxidation at different intensity and membrane dysfunction of human erythrocytes in hyperglycemia.

  3. Protective Effect of Onion Extract on Bleomycin-Induced Cytotoxicity and Genotoxicity in Human Lymphocytes

    Yoon Hee Cho

    2016-02-01

    Full Text Available Following one of the world’s largest nuclear accidents, occured at Fukushima, Japan in 2011, a significant scientific effort has focused on minimizing the potential adverse health effects due to radiation exposure. The use of natural dietary antioxidants to reduce the risk of radiation-induced oxidative DNA damage is a simple strategy for minimizing radiation-related cancer rates and improving overall health. The onion is among the richest sources of dietary flavonoids and is an important food for increasing their overall intake. Therefore, we examined the effect of an onion extract on cyto- and geno-toxicity in human lymphocytes treated with bleomycin (BLM, a radiomimetic agent. In addition, we measured the frequency of micronuclei (MN and DNA damage following treatment with BLM using a cytokinesis-blocked micronucleus assay and a single cell gel electrophoresis assay. We observed a significant increase in cell viability in lymphocytes treated with onion extract then exposed to BLM compared to cells treated with BLM alone. The frequency of BLM induced MN and DNA damage increased in a dose-dependent manner; however, when lymphocytes were pretreated with onion extract (10 and 20 μL/mL, the frequency of BLM-induced MN was decreased at all doses of BLM and DNA damage was decreased at 3 μg/mL of BLM. These results suggest that onion extract may have protective effects against BLM-induced cyto- and genotoxicity in human lymphocytes.

  4. Radio response of human lymphocytes pretreated with boron and gadoliniums assessed by the, comet assay

    Kim, J. K.; Park, T. W.; Cebulska-Wasiewska, A.; Nili, M.

    2009-01-01

    Boron and gadolinium are among the nuclides that hold a unique property of being a neutron capture therapy agent. Neutron beams have often a considerable portion of gamma rays with fast neutrons. Gamma rays, as beam contaminants, can cause considerable damage to normal tissues even if such tissues do contain high boron concentrations. Materials and Methods: The modification of radio response in human lymphocytes pretreated with boron or gadolinium compound was studied by assessing the DNA damage using single cell gel electrophoresis, the comet assay. The lymphocytes from the human peripheral blood were irradiated with 0, 1, 2 and 4 Gy of gamma rays from a 60 Co isotopic source with or without pretreatment of boron or gadolinium compound for 10 minutes at 4 d egree C . Post-irradiation procedures included slide preparation, cell-lysing, unwinding and electrophoresis, neutralization, staining, and analytic steps, gel electrophoresis. Results: The results indicate that pretreatment with boron compound (50 n M or 250 n M of 10 B) is effective in reducing the radiosensitivity of the lymphocyte DNA. Conversely, pretreatment with gadolinium compound (50 n M) led to a dose-dependent increase in the radiosensitivity, most prominently with a dose of 4 Gy (P<0.001). Furthermore, when the lymphocytes were pretreated with a Combined mixture (1:1) of boron (250 n M) and gadolinium (50 n M) compounds, the reduced radiosensitivity was also observed.

  5. Reference values of CD4 T-lymphocytes in human ...

    exposed uninfected infants in Kano.Nigeria. ... Journal of Medicine in the Tropics ... Studies to evaluate CD4 count in vertically exposed, but human immunodeficiency virus (HIV) negative infants from this region have not been done previously.

  6. Two small lymphocyte subpopulations in human peripheral blood. I. Purification and surface marker profiles

    Hokland, M; Hokland, P; Heron, I

    1978-01-01

    By means of simple rosette sedimentation methods two subsets from human peripheral blood lymphocytes have been isolated: (1) (E, Fc)- and (2) (E, Ig)-. The first subset was obtained by centrifuging suspensions of macrophage-depleted PBL in which E and EA rosettes had been allowed to form simultan......By means of simple rosette sedimentation methods two subsets from human peripheral blood lymphocytes have been isolated: (1) (E, Fc)- and (2) (E, Ig)-. The first subset was obtained by centrifuging suspensions of macrophage-depleted PBL in which E and EA rosettes had been allowed to form...... simultaneously. The dominant marker of these E- Fc- cells was surface Ig, and during 4 days of culture this population did not alter its surface markers. Subset 2 was obtained in two ways following rosette centrifugation with AET-treated SRBC and rabbit anti-human Ig-coated autologous RBC. This 'Null cell...

  7. Characterization of a novel human scavenger receptor cysteine-rich molecule SCART1 expressed by lymphocytes

    Holm, D.; Fink, D. R.; Steffensen, M. A.

    2013-01-01

    a member of the SRCR superfamily, mSCART1, which primarily is expressed on a large subset of γδ T cells in mice. Here we report the cloning and characterization of human SCART1 (hSCART1) mainly expressed by CD4(+) and CD8(+) T lymphocytes. The hSCART1 gene maps to chromosome 10, region q26.3, a region...... domain. Shorter splice forms have also been isolated. Quantitative real-time PCR analysis on human blood-fractions has shown that hSCART1 is expressed primarily by CD4(+) and CD8(+) T lymphocytes with either αβ or γδ T cell receptors, and real-time PCR on 22 different human tissues showed high expression...... that the protein plays a role in the immune system, perhaps as a co-receptor on αβ and γδ T cells....

  8. Suppressive effects of chlorphenesin on lymphocyte function in mice and humans.

    Stites, D P; Brecher, G; Schmidt, L; Berger, F M

    1979-12-01

    The immunosuppressive action of chlorphenesin was investigated in a wide variety of in vitro assays for cellular immunity in humans and mice. Chlorphenesin, at doses of 20-50 micrograms/ml, inhibited mitogenic responses of both mouse and human B and T cells. These doses did not kill cells exposed to the drug for 72 hr. Mixed lymphocyte reactions in inbred strains of mice and in unrelated humans were also inhibited at concentrations of about 50 micrograms/ml. However, the generation of cytotoxic T cells in cell-mediated lympholysis assays was not inhibited to the same degree as proliferation in mixed lymphocyte reaction and the cytotoxic potential of presensitized mouse T cells for allogeneic targets was totally unaffected. These studies suggest that chlorphenesin may have a broad spectrum of suppressive effects both on T and B cells and that the predominant inhibition of proliferative responses in these cells may reduce the expansion of clones of immunocompetent cells in vivo.

  9. Quantitative non-invasive intracellular imaging of Plasmodium falciparum infected human erythrocytes

    Edward, Kert; Farahi, Faramarz

    2014-01-01

    Malaria is a virulent pathological condition which results in over a million annual deaths. The parasitic agent Plasmodium falciparum has been extensively studied in connection with this epidemic but much remains unknown about its development inside the red blood cell host. Optical and fluorescence imaging are among the two most common procedures for investigating infected erythrocytes but both require the introduction of exogenous contrast agents. In this letter, we present a procedure for the non-invasive in situ imaging of malaria infected red blood cells. The procedure is based on the utilization of simultaneously acquired quantitative phase and independent topography data to extract intracellular information. Our method allows for the identification of the developmental stages of the parasite and facilitates in situ analysis of the morphological changes associated with the progression of this disease. This information may assist in the development of efficacious treatment therapies for this condition. (letters)

  10. A study on the complexes between human erythrocyte enzymes participating in the conversions of 1,3-diphosphoglycerate.

    Fokina, K V; Dainyak, M B; Nagradova, N K; Muronetz, V I

    1997-09-15

    The ability of D-glyceraldehyde-3-phosphate dehydrogenase (GAPDH) catalyzing the reaction of 1,3-diphosphoglycerate synthesis in human erythrocytes to form complexes with enzymes which use this metabolite as substrate (3-phosphoglycerate kinase (3-PGK) or 2,3-diphosphoglycerate mutase (2,3-DPGM)) was studied. It was found that highly active 2,3-DPGM can be extracted from human erythrocyte hemolysates in a complex with GAPDH adsorbed on Sepharose-bound anti-GAPDH antibodies at pH 6.5, the molar ratio being one 2,3-GPGM subunit per subunit of GAPDH. No complexation was, however, detected at pH 8.0. The opposite was true for the interaction between GAPDH and 3-PGK, which could be observed at pH 8.0. In experiments carried out at pH 7.4, both GAPDH x 2,3-DPGM and GAPGH x 3-PGK complexes were detected. The Kd values of the complexes determined with purified enzyme preparations were in the range 2.40-2.48 microM for both the GAPDH x 2,3-DPGM and GAPGH x 3-PGK enzyme pairs, when titrations of GAPDH covalently bound to CNBr-activated Sepharose were performed by the soluble 2,3-DPGM or 3-PGK. If, however, GAPDH adsorbed on the specific antibodies covalently bound to Sepharose was used in the titration experiments, the Kd for the GAPDH x 2,3-DPGM complex was found to be 0.54 microM, and the Kd for the GAPDH x 3-PGK complex was 0.49 microM. The concentration of 2,3-diphosphoglycerate determined after 1 h of incubation of erythrocytes in the presence of glucose was found to increase 1.5-fold if the incubation was carried out at pH 6.5, but did not change upon incubation at pH 8.0. On the other hand, the concentration of 3-phosphoglycerate after incubation at pH 8.0 was twice as large as that found after incubation at pH 6.5. The results are interpreted on the hypothesis that specific protein-protein interactions between GAPDH and 2,3-DPGM or between GAPDH and 3-PGK may play a role in determining the fate of 1,3-diphosphoglycerate produced in the GAPDH-catalyzed reaction.

  11. The influence of Bauhinia forficata Link subsp. pruinosa tea on lipid peroxidation and non-protein SH groups in human erythrocytes exposed to high glucose concentrations.

    Salgueiro, Andréia C F; Leal, Carina Q; Bianchini, Matheus C; Prado, Ianeli O; Mendez, Andreas S L; Puntel, Robson L; Folmer, Vanderlei; Soares, Félix A; Avila, Daiana S; Puntel, Gustavo O

    2013-06-21

    Bauhinia forficata (BF) has been traditionally used as tea in folk medicine of Brazil for treatment of Diabetes mellitus (DM). To evaluate the effects of BF leaf tea on markers of oxidative damage and antioxidant levels in an experimental model of hyperglycemia in human erythrocytes in vitro. Human erythrocytes were incubated with high glucose concentrations or glucose and BF tea for 24h and 48h. After incubation lipid peroxidation and non-protein SH levels were analyzed. Moreover, quantification of polyphenols and flavonoids, iron chelating property, scavenging of DPPH, and prevention of lipid peroxidation in isolated lipids were also assessed. A significant amount of polyphenols and flavonoids was observed. The main components found by LC-MS analysis were quercetin-3-O-(2-rhamnosyl) rutinoside, kaempferol-3-O-(2-rhamnosyl) rutinoside, quercetin-3-O-rutinoside and kaempferol-3-O-rutinoside. BF tea presents important antioxidant and chelating properties. Moreover, BF tea was effective to increase non-protein SH levels and reduce lipid peroxidation induced by high glucose concentrations in human erythrocytes. The antioxidant effects of BF tea could be related to the presence of different phenolic and flavonoids components. We believe that these components can be responsible to protect human erythrocytes exposed to high glucose concentrations against oxidative damage. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  12. Changes in the Fatty Acid Profile and Phospholipid Molecular Species Composition of Human Erythrocyte Membranes after Hybrid Palm and Extra Virgin Olive Oil Supplementation.

    Pacetti, D; Gagliardi, R; Balzano, M; Frega, N G; Ojeda, M L; Borrero, M; Ruiz, A; Lucci, P

    2016-07-13

    This work aims to evaluate and compare, for the first time, the effects of extra virgin olive oil (EVOO) and hybrid palm oil (HPO) supplementation on the fatty acid profile and phospholipid (PL) molecular species composition of human erythrocyte membranes. Results supported the effectiveness of both HPO and EVOO supplementation (3 months, 25 mL/day) in decreasing the lipophilic index of erythrocytes with no significant differences between HPO and EVOO groups at month 3. On the other hand, the novel and rapid ultraperformance liquid chromatography-tandem mass spectrometry method used for PL analysis reveals an increase in the levels of phosphatidylcholine and phosphatidylethanolamine species esterified with polyunsaturated fatty acids. This work demonstrates the ability of both EVOO and HPO to increase the degree of unsaturation of erythrocyte membrane lipids with an improvement in membrane fluidity that could be associated with a lower risk of developing cardiovascular diseases.

  13. Is the Oxidative DNA Damage Level of Human Lymphocyte Correlated with the Antioxidant Capacity of Serum or the Base Excision Repair Activity of Lymphocyte?

    Yi-Chih Tsai

    2013-01-01

    Full Text Available A random screening of human blood samples from 24 individuals of nonsmoker was conducted to examine the correlation between the oxidative DNA damage level of lymphocytes and the antioxidant capacity of serum or the base excision repair (BER activity of lymphocytes. The oxidative DNA damage level was measured with comet assay containing Fpg/Endo III cleavage, and the BER activity was estimated with a modified comet assay including nuclear extract of lymphocytes for enzymatic cleavage. Antioxidant capacity was determined with trolox equivalent antioxidant capacity assay. We found that though the endogenous DNA oxidation levels varied among the individuals, each individual level appeared to be steady for at least 1 month. Our results indicate that the oxidative DNA damage level is insignificantly or weakly correlated with antioxidant capacity or BER activity, respectively. However, lymphocytes from carriers of Helicobacter pylori (HP or Hepatitis B virus (HBV tend to give higher levels of oxidative DNA damage (P<0.05. Though sera of this group of individuals show no particular tendency with reduced antioxidant capacity, the respective BER activities of lymphocytes are lower in average (P<0.05. Thus, reduction of repair activity may be associated with the genotoxic effect of HP or HBV infection.

  14. Human gamma interferon production by cytotoxic T lymphocytes sensitized during hepatitis A virus infection

    Maier, K.; Gabriel, P.; Koscielniak, E.; Stierhof, Y.D.; Wiedmann, K.H.; Flehmig, B.; Vallbracht, A.

    1988-01-01

    The production of interferon (IFN) during a chromium-51 release assay with hepatitis A virus (HAV)-infected fibroblasts and autologous peripheral blood lymphocytes from patients with acute HAV infection was studied to determine whether IFN plays a role in immunopathogenesis of hepatitis A infection in humans. Skin fibroblasts of eight patients after acute HAV infection and from two control persons without history of current of past HAV infection were infected with HAV. Peripheral blood lymphocytes were collected at different times after the onset of icterus and tested in a chromium-51 release assay against autologous HAV-infected skin fibroblasts for their cytolytic and IFN-producing activity. The IFN produced during the assay was characterized and found to have the properties of human gamma IFN. Cytotoxicity and gamma IFN release were virus specific. The cell types responsible for both functions were characterized and found to be in the HLA-dependent T8 + lymphocyte subset. Considering that gamma IFN has an antiviral effect on persistent HAV infection in vitro and that it probably accounts for stimulation of HLA class I antigen expression on hepatocytes, these experimental results presented here demonstrate that human gamma IFN produced by HAV-specific T cells may participate in pathogenesis of hepatitis A infection in humans

  15. Human cord blood suppressor T lymphocytes. II. Characterization of inducer of suppressor cells

    Cheng, H.; Delespesse, G.

    1986-01-01

    Previously, we reported an antigen nonspecific inducer of T suppressor cell factor (TisF) produced by cord blood mononuclear cells (MNC) in 48-hr, two-way mixed lymphocyte cultures (MLC). The target of this factor was a radiosensitive, T4+ (T8-) adult suppressor T cell subset. The cellular origin of this TisF was examined in the present study. IgG production by pokeweed mitogen (PWM)-stimulated adult MNC was used as an assay for TisF activity. It was found that TisF-producing cells formed rosettes with sheep erythrocytes (E+) and were independent of adherent cells (AC) in the production of TisF. They were resistant to irradiation (2500 rads) and phenotypic characterization with T cell reactive monoclonal antibodies indicated that they resided in the T8- (T4+) population. Furthermore, both TQ1- and TQ1+ cells were required for the production of TisF activity and such activity could not be reconstituted by supernatants from TQ1- MLC and TQ1+ MLC. These results indicate that the production of TisF is dependent upon interactions between radioresistant E+, T8-, TQ1- and radioresistant E+, T8-, TQ1+ cells

  16. Equilibrium thermodynamics of the partitioning of non-steroidal anti-inflammatory drugs into human erythrocyte ghost membranes

    Omran, Ahmed A.

    2013-01-01

    Graphical abstract: Bar diagram representing thermodynamic parameters obtained for the partitioning of NSAIDs into human erythrocyte ghost membranes at physiological pH; 7.4. Highlights: • Partition coefficients of NSAIDs into HEG membranes were determined. • Thermodynamic parameters were evaluated and successfully analyzed. • Partitioning of NSAIDs into HEG membranes was exothermic. • Partitioning of NSAIDs into HEG is spontaneous with negative free energy values. • Identical partitioning enthalpy–entropy driven compensation mechanism was shown. -- Abstract: In this work,second derivative spectrophotometry was applied for determining the partition coefficients (K p s) of four non-steroidal anti-inflammatory drugs (NSAIDs; flufenamic, meclofenamic, mefenamic and niflumic acids) into human erythrocyte ghost (HEG) membranes over a temperature range from (283.2 to 313.2) K. The proposed method allowed the evaluation and direct analyses of thermodynamic parameters; enthalpy (ΔH W→M ), Gibbs energy (ΔG W→M ) and entropy (ΔS W→M ) changes of the partitioning of NSAIDs into HEG membranes. The partitioning of NSAIDs between polar aqueous phase and non-polar lipid bilayer HEG membrane phase was exothermic with negative (ΔH W→M ) which compensated for the changes in (ΔS W→M ). The negative values of (ΔG W→M ) revealed that the partitioning of NSAIDs into HEG, owing to their transfer from polar aqueous phase and non-polar HEG phase is spontaneous. The enthalpy–entropy correlation analysis resulted in a good linearity that suggests an identical partitioning enthalpy–entropy driven compensation mechanism for the studied NSAIDs

  17. Highly Selective Fluorescence Determination of the Hematin Level in Human Erythrocytes with No Need for Separation from Bulk Hemoglobin.

    Ji, Lijuan; Chen, Li; Wu, Ping; Gervasio, Dominic F; Cai, Chenxin

    2016-04-05

    Hematin-induced fluorescence quenching of boron-doped graphene quantum dots (BGQDs) allows for determination of hematin concentration in human erythrocytes with no need for separating hematin from hemoglobin before performing the assay. The BGQDs are made by oxidizing a graphite anode by holding the voltage between a graphite rod and a Pt cathode at 3 V for 2 h in an aqueous borax solution at pH 7; then, the borate solution was filtered with BGQDs, and the borate was dialyzed from the filtrate, leaving a solution of BGQDs in water. The fluorescence intensity of BGQDs is measurable in real time, and its quenching is very sensitive to the concentration of hematin in the system but not to other coexisting biological substances. The analytical signal is defined as ΔF = 1 - F/F0, where F0 and F are the fluorescence intensities of the BGQDs before and after interaction with hematin, respectively. There is a good linear relationship between ΔF and hematin concentration, ranging from 0.01 to 0.92 μM, with the limit of detection (LOD) being ∼0.005 ± 0.001 μM at a signal-to-noise ratio of 3. This new method is sensitive, label-free, simple, and inexpensive, and many tedious procedures related to sample separation and preparation can be omitted, implying that this method has potential for applications in clinical examinations and disease diagnoses. For example, the determination of the hematin levels in two kind of red blood cell samples, healthy human and sickle cell erythrocytes, gives average concentrations of hematin of ∼(23.1 ± 4.9) μM (average of five samples) for healthy red cell cytosols and ∼(52.5 ± 9.5) μM (average of two samples) for sickle red cell cytosols.

  18. Circular chromatin complexes in human lymphocytes high-resolution autoradiography

    Becak, M.L.; Fukuda-Pizzocaro, K.; Santos, R. de C.S. dos; Brunner, O.

    1985-01-01

    Transcriptionally active chromatin fibers were observed in chromosomes presenting the loops/scaffold configuration. The active fibers showed altered nucleosomes and presented multiforked aspects which led to the formation of ring complexes. The ribonucleoprotein transcripts (RNP) appeared as networks of 0.1 μm or multiples tandemly disposed along the fiber. It is suggested that the ring complexes belong to the human genome. The possibility that these circular structures come from a prokaryote is also considered. (author) [pt

  19. Effects of mercury on the proliferation of human peripheral lymphocytes in vitro

    Piwecka, K.; Poniedzialek, B.; Rzymski, P.; Karczewski, J.; Zurawski, J.; Wiktorowicz, K.

    2011-01-01

    Our project aimed to investigate the effects of mercury on the proliferation of human peripheral lymphocytes in vitro. The lymphocytes were isolated from the blood collected from healthy donors at Regionalne Centrum Krwiodawstwa i Krwiolecznictwa in Poznan, Poland. For the purpose of cell culture, the lymphocyte suspension (25 · 10 4 cells/ml) in Eagle's medium supplemented with 10% fetal calf serum was prepared. Phytohaemagglutinin-L (PHA-L) was used in a concentration of 2.5 mg/ml to stimulate cell proliferation. Mercuric chloride (HgCl 2 ) in four different concentrations (1 μM, 10 μM, 50 μM, 100 μM) and [3H]-thymidine were added after 48 hours of incubation and the cell culture was continued for the next 24 hours. The rate of lymphocyte proliferation was measured by [3H]-thymidine incorporation method with a liquid scintillation counter. Results indicate that higher concentrations of mercury (50 μM, 100 μM) inhibit the [3H]-thymidine incorporation of human peripheral lymphocytes in vitro. The incorporation was lower than the control sample by 65% at a concentration of 50 μM, while at a concentration of 100 μM it fell to virtually zero. Moreover, the phase of lymphocyte proliferation cycle affected by mercuric chloride was also investigated. For this purpose HgCl 2 in 2 concentrations (10 μM, 50 μM) was added to the cell culture in 4 different time points: at the start of the cell culture and after 4, 24, and 48 hours of incubation. After 48 hours, [3H]-thymidine was added and the cell culture was continued for an additional 24 hours. The rate of cell proliferation was estimated by [3H]-thymidine incorporation using a liquid scintillation counter. The inhibition effect was observed in samples with metal added at the start of the cell culture and after 4 h of incubation, i.e. at the initial phase of the lymphocyte proliferation cycle. (authors)

  20. Protective effect of allium sativum ethanol extract on cultured human lymphocytes against electron beam radiation

    Rao, Shama; Shetty, Sukanya; Suchetha Kumari; Madhu, L.N.

    2013-01-01

    The development of radioprotective agent has been the subject of intense research because exposure to ionizing radiation causes DNA damage which may cause mutation and ultimately leads to cancer, on the other hand radiotherapy has become an integral part in treatment of cancer which uses ionizing radiations like X rays, gamma rays to kill the cancer cells. Amifostine is a well-known radioprotector which is clinically approved. There are many other radioprotectors like cysteine, cystamine, serotine but they are not used because of its normal tissue toxicity. Allium sativum is commonly known as garlic which has already been reported for its medicinal properties. In this study we evaluated radioprotection property of Allium sativum on DNA damage caused by electron beam radiation in cultured human lymphocytes. Allium sativum ethanol extract was used for this study. Cell viability was performed by MTT assay. DNA damage was assessed by comet assay parameters. The cultured lymphocytes were incubated with different concentrations 10, 50 and 100 μg/mL of Allium sativum extracts for 2, 4, 6 and 24 hour time intervals. Treatment of lymphocytes with various concentration of Allium sativum extract resulted in significant decrease in the level of DNA damage (Percentage tail DNA 6%) and increase in cell viability 93% (p>0.05) compare to the radiation control group. Results of this study revealed that Allium sativum protects cultured lymphocytes when exposed to electron beam radiation at its sub lethal dose. (author)

  1. β-Adrenergic receptor-mediated suppression of interleukin 2 receptors in human lymphocytes

    Feldman, R.D.; Hunninghake, G.W.; McArdle, W.L.

    1987-01-01

    Adrenergic receptor agonists are know to attenuate the proliferative response of human lymphocytes after activation; however, their mechanism of action is unknown. Since expression of interleukin 2 (IL-2) receptors is a prerequisite for proliferation, the effect of β-adrenergic receptor agonists on lymphocyte IL-2 receptors was studied on both mitogen-stimulated lymphocytes and IL-2-dependent T lymphocyte cell lines. In both cell types the β-adrenergic receptor agonist isoproterenol blocked the expression of IL-2 receptors, as determined with the IL-2 receptor anti-TAC antibody. To determine the effect of β-adrenergic agonists on expression of the high affinity IL-2 receptors, [ 125 I]IL-2 binding studies were performed at concentrations selective for high affinity sites. No significant effect of β-adrenergic agonists on high affinity IL-2 receptor sites could be detected. The data demonstrate that β-adrenergic receptor agonists down-regulate IL-2 receptors primarily affecting low affinity sites

  2. Staining human lymphocytes and onion root cell nuclei with madder root.

    Cücer, N; Guler, N; Demirtas, H; Imamoğlu, N

    2005-01-01

    We performed staining experiments on cells using natural dyes and different mordants using techniques that are used for wool and silk dyeing. The natural dye sources were madder root, daisy, corn cockle and yellow weed. Ferrous sulfate, copper sulfate, potassium tartrate, urea, potassium aluminum sulfate and potassium dichromate were used as mordants. Distilled water, distilled water plus ethanol, heptane, and distilled water plus methanol were used as solvents. All dye-mordant-solvent combinations were studied at pH 2.4, 3.2 and 4.2. The generic staining procedure was to boil 5-10 onion roots or stimulated human lymphocyte (SHL) preparations in a dye bath on a hot plate. Cells were examined at every half hour. For multicolor staining, madder-dyed lymphocytes were decolorized, then stained with Giemsa. The AgNOR technique was performed following the decolorization of Giemsa stained lymphocytes. Good results were obtained for both onion root cells and lymphocytes that were boiled for 3 h in a dye bath that included 4 g madder root, 4 g ferrous sulfate as mordant in 50 ml of 1:1 (v/v) methanol:distilled water. The pH was adjusted to 4.2 with 6 ml acetic acid. We conclude that madder root has potential as an alternative dye for staining biological materials.

  3. Preliminary study on biological dosimetry using alkaline single cell gel electrophoresis of human peripheral lymphocytes

    Liu Qingjie; Lu Xue; Feng Jiangbing; Chen Deqing; Chen Xiaosui

    2006-01-01

    Objective: To explore the feasibility of alkaline single cell gel electrophoresis (SCGE) in biological dosimetry of ionizing radiation. Methods: Normal peripheral blood samples from two healthy males were exposed to different doses coblat-60 gamma-rays, ranged from 0 to 5 Gy, and the tail length (TL) and Oliver tail moment (TM) of the lymphocytes were analyzed with SCGE. The dose-effect curves of TL and TM were fitted respectively. The TL and TM of lymphocytes for eight radiation workers were analyzed with SCGE, cumulative doses were estimated using the fitted TL and TM equations, and then compared with the recorded monitoring doses. Results: The TLs or TMs of normal human lymphocytes were increased with the irradiation doses, and its relationship can be fitted with a linear-quadratic equations: Y=13.59 + 20.87X - 2.27 X 2 for TL, and Y = 8.50 + 15.04X - 1.43X 2 for TM, respectively (Y denotes TL or TM value, X is radiation dose). The doses estimated with TM equation were closer to the recorded monitoring doses than that with TL equation. Conclusions: The TM in lymphocytes analyzed with SCGE is a promising radiation biological dosimeter. (authors)

  4. Hapten-specific lymphocyte transformation in humans sensitized with NDMA or DNCB.

    SoebergB; Andersen, V

    1976-01-01

    The primary immune response to a contact sensitizing dose of para-N-dimethylnitrosaniline (NDMA) and dinitrochlorobenzene (DNCB) was obtained in humans and measured in vitro by increased thymidine incorporation into sensitized lymphocytes. No cross-reaction was found between these two haptens, and it is thus possible on two separate occasions to quantify and follow the primary cellular immune response in man. PMID:963911

  5. In Vitro Genotoxic Effects of Four Helichrysum Species in Human Lymphocytes Cultures

    Erolu, Erhan H; Hamzaolu, Ergin; Aksoy, Ahmet; Budak, Ümit; Özkul, Yusuf

    2010-01-01

    Helichrysum sanguineum, Helichrysum pamphylicum, Helichrysum orientale, Helichrysum noeanum (Asteraceae) are medicinal plants. For centuries, they have been used as tea in Turkey because of their medicinal properties. So far no scientifc evidence has been found in a literature survey regarding the genotoxic effects of these plants. This work evaluated the genotoxic effects on human lymphocyte cultures induced by methanol extracts of these plants, assayed in different concentrations (0.01, 0.0...

  6. Differential expression of the human thymosin-β4 gene in lymphocytes, macrophages, and granulocytes

    Gondo, H.; Kudo, J.; White, J.W.; Barr, C.; Selvanayagam, P.; Saunders, G.F.

    1987-01-01

    A cDNA clone encoding human thymosin-β 4 was isolated from a cDNA library prepared from peripheral blood leukocytes of a patient with acute lymphocytic leukemia. This clone contained the entire coding sequence of 43 amino acid residues of thymosin-β 4 and had an initiation codon and two termination codons. The amino acid and nucleotide sequences in the coding region were well conserved between rat and human. No signal peptide was found in the deduced protein sequence. Human thymosin-β 4 mRNA, approximately 830 nucleotides in length, was about 30 nucleotides larger than rat thymosin-β 4 mRNA. Expression of the human thymosin-β 4 gene in various primary myeloid and lymphoid malignant cells and in a few human hemopoietic cell lines was studied. Northern blot analyses of different neoplastic B lymphocytes revealed that steady state levels of thymosin-β 4 mRNA varied as a function of differentiation stage. Thymosin-β 4 mRNA levels were decreased in myeloma cells as are class II human leukocyte antigen, Fc receptor, and complement receptor, suggesting a relationship between thymosin-β 4 and the immune response. Treatment of THP-1 cells, a human monocytic cell line, with recombinant human interferon-γ reduced the levels of thymosin-β 4 mRNA. The pattern of thymosin-β 4 gene expression suggests that it may play a fundamental role in the host defense mechanism

  7. A Role for T-Lymphocytes in Human Breast Cancer and in Canine Mammary Tumors

    Maria Isabel Carvalho

    2014-01-01

    Full Text Available Chronic inflammation in the tumor microenvironment has a prominent role in carcinogenesis and benefits the proliferation and survival of malignant cells, promoting angiogenesis and metastasis. Mammary tumors are frequently infiltrated by a heterogeneous population of immune cells where T-lymphocytes have a great importance. Interestingly, similar inflammatory cell infiltrates, cytokine and chemokine expression in humans and canine mammary tumors were recently described. However, in both species, despite all the scientific evidences that appoint for a significant role of T-lymphocytes, a definitive conclusion concerning the effectiveness of T-cell dependent immune mechanisms has not been achieved yet. In the present review, we describe similarities between human breast cancer and canine mammary tumors regarding tumor T-lymphocyte infiltration, such as relationship of TILs and mammary tumors malignancy, association of ratio CD4+/ CD8+ T-cells with low survival rates, promotion of tumor progression by Th2 cells actions, and association of great amounts of Treg cells with poor prognostic factors. This apparent parallelism together with the fact that dogs develop spontaneous tumors in the context of a natural immune system highlight the dog as a possible useful biological model for studies in human breast cancer immunology.

  8. Differential expression gene profiling in human lymphocyte after 6 h irradiated

    Li Jianguo; Qin Xiujun; Zhang Wei; Xu Chaoqi; Li Weibin; Dang Xuhong; Zuo Yahui

    2011-01-01

    Objective: To provide the evidence of health damage for the staff irradiated from the gene level. Methods: The study analyzed the differential transcriptional profile of normal human lymphocyte and human lymphocyte irradiated with 0.1 Gy, 0.2 Gy, 0.5 Gy, 1.0 Gy by whole genome chip after 6 h irradiated. Results: The results showed that there were 1177 differentially expressed genes with 0.1 Gy after 6 h irradiation, and there were 1922 differentially expressed genes with 0.2 Gy after 6 h irradiation, and there were 492 differentially expressed genes with 0.5 Gy after 6 h irradiation, 2615 differentially expressed genes with 1.0 Gy after 6 h irradiation, 114 differentially expressed genes in 4 dose points after 6 h irradiation. RT-PCR results indicated that the relative quantity's result of EGR1, HLA-DMB and TAIAP1 was consistent with gene chip data. Conclusion: The study found many significant different genes in human lymphocyte with different doses after 6 h irradiation, which will provide a basis for the further radiation-different-genes and the mechanism of radiation damage. (authors)

  9. Presence of adenovirus species C in infiltrating lymphocytes of human sarcoma.

    Karin Kosulin

    Full Text Available Human adenoviruses are known to persist in T-lymphocytes of tonsils, adenoids and intestinal tract. The oncogenic potential of different adenovirus types has been widely studied in rodents, in which adenovirus inoculation can induce multiple tumors such as undifferentiated sarcomas, adenocarcinomas and neuroectodermal tumors. However, the oncogenic potential of this virus has never been proven in human subjects. Using a highly sensitive broad-spectrum qRT-PCR, we have screened a set of different human sarcomas including leiomyosarcoma, liposarcoma and gastro intestinal stroma tumors. Primers binding the viral oncogene E1A and the capsid-coding gene Hexon were used to detect the presence of adenovirus DNA in tumor samples. We found that 18% of the tested leiomyosarcomas and 35% of the liposarcomas were positive for the presence of adenovirus DNA, being species C types the most frequently detected adenoviruses. However, only in one sample of the gastro intestinal stroma tumors the virus DNA could be detected. The occurrence of adenovirus in the tumor sections was confirmed by subsequent fluorescence in-situ-hybridization analysis and co-staining with the transcription factor Bcl11b gives evidence for the presence of the virus in infiltrating T-lymphocytes within the tumors. Together these data underline, for the first time, the persistence of adenovirus in T-lymphocytes infiltrated in muscular and fatty tissue tumor samples. If an impaired immune system leads to the viral persistence and reactivation of the virus is involved in additional diseases needs further investigation.

  10. Application of human erythrocytes to a radioimmune assay of immune complexes in serum. [Lupus erythematosus, type B hepatitis

    Tsuda, F; Miyakawa, Y; Mayumi, M [Tokyo Metropolitan Lab. of Public Health (Japan)

    1979-07-01

    An immune adherence receptor exists on the surface of primate erythrocytes, and has been characterized as a receptor for the activated third component of complement (C3b). Human red blood cells (RCBs, blood group O) were applied to a sensitive determination of complement-fixing, soluble immune complexes in serum. The method involved the binding of immune complexes with RBCs in the presence of complement and the detection of cell-bound IgG molecules by radiolabelled anti-human IgG antibodies. Since the binding of RBCs with monomeric IgG was minimal, cell bound IgG molecules were taken as representing immune complexes. When aggregated human gammaglobulin (AHG) was used as a model of immune complexes, as little as 5 ..mu..g dissolved in 1 ml of normal human serum were detected. The binding of RBCs with AHG was inhibited in EDTA solution where the classical complement pathway could not be activated. The RBC radioimmune assay was successfully applied to the determination of soluble immune complexes in pathological serum samples obtained from the patients with systemic lupus erythematosus and those with fulminant Type B hepatitis. False-positive results by autoantibodies against RBCs could be excluded by a Coombs test and by comparing the binding in the presence of complement with that in EDTA solution. The ubiquitous availability of RBCs coupled with a high sensitivity would allow the RBC radioimmune assay to be used as a further method of determining immune complexes in the serum.

  11. Human antibodies fix complement to inhibit Plasmodium falciparum invasion of erythrocytes and are associated with protection against malaria.

    Boyle, Michelle J; Reiling, Linda; Feng, Gaoqian; Langer, Christine; Osier, Faith H; Aspeling-Jones, Harvey; Cheng, Yik Sheng; Stubbs, Janine; Tetteh, Kevin K A; Conway, David J; McCarthy, James S; Muller, Ivo; Marsh, Kevin; Anders, Robin F; Beeson, James G

    2015-03-17

    Antibodies play major roles in immunity to malaria; however, a limited understanding of mechanisms mediating protection is a major barrier to vaccine development. We have demonstrated that acquired human anti-malarial antibodies promote complement deposition on the merozoite to mediate inhibition of erythrocyte invasion through C1q fixation and activation of the classical complement pathway. Antibody-mediated complement-dependent (Ab-C') inhibition was the predominant invasion-inhibitory activity of human antibodies; most antibodies were non-inhibitory without complement. Inhibitory activity was mediated predominately via C1q fixation, and merozoite surface proteins 1 and 2 were identified as major targets. Complement fixation by antibodies was very strongly associated with protection from both clinical malaria and high-density parasitemia in a prospective longitudinal study of children. Ab-C' inhibitory activity could be induced by human immunization with a candidate merozoite surface-protein vaccine. Our findings demonstrate that human anti-malarial antibodies have evolved to function by fixing complement for potent invasion-inhibitory activity and protective immunity. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  12. Growth of plasmodium falciparum in human erythrocytes containing abnormal membrane proteins

    Schulman, S.; Roth, E.F. Jr.; Cheng, B.; Rybicki, A.C.; Sussman, I.I.; Wong, M.; Nagel, R.L.; Schwartz, R.S.; Wang, W.; Ranney, H.M.

    1990-01-01

    To evaluate the role of erythrocyte (RBC) membrane proteins in the invasion and maturation of Plasmodium falciparum, the authors have studied, in culture, abnormal RBCs containing quantitative or qualitative membrane protein defects. These defects included hereditary spherocytosis (HS) due to decreases in the content of spectrin [HS(Sp + )], hereditary elliptocytosis (HE) due to protein 4.1 deficiency [HE(4.1 0 )], HE due to a spectrin αI domain structural variant that results in increased content of spectrin dimers [HE(Spα I/65 )], and band 3 structural variants. Parasite invasion, measured by the initial uptake of [ 3 H]hypoxanthine 18 hr after inoculation with merozoites, was normal in all of the pathologic RBCs. In contrast, RBCs from six HS(Sp + ) subjects showed marked growth inhibition that became apparent after the first or second growth cycle. The extent of decreased parasite growth in HS(Sp + ) RBCs closely correlated with the extent of RBC spectrin deficiency. Homogeneous subpopulations of dense HS RBCs exhibited decreased parasite growth to the same extent as did HS whole blood. RBCs from four HE subjects showed marked parasite growth and development

  13. Mercuric dichloride induces DNA damage in human salivary gland tissue cells and lymphocytes

    Schmid, Katharina; Kroemer, Susanne [University of Regensburg, Regensburg (Germany); Sassen, Andrea [University of Regensburg, Department of Pathology, Regensburg (Germany); Staudenmaier, Rainer [Technical University of Munich, Department of Otorhinolaryngology, Head and Neck Surgery, Munich (Germany); Reichl, Franz-Xaver [University of Munich, Institute of Pharmacology and Toxicology, Munich (Germany); Harreus, Ulrich [University of Munich, Department of Otorhinolaryngology, Head and Neck Surgery, Munich (Germany); Hagen, Rudolf; Kleinsasser, Norbert [University of Wuerzburg, Department of Otorhinolaryngology, Head and Neck Surgery, Wuerzburg (Germany)

    2007-11-15

    Amalgam is still one of the most frequently used dental filling materials. However, the possible adverse effects especially that of the mercuric component have led to continued controversy. Considering that mercury may be released from amalgam fillings into the oral cavity and also reach the circulating blood after absorption and resorption, it eventually may contribute to tumorigenesis in a variety of target cells. The present investigation focuses on genotoxic effects below a cytotoxic dose level of mercuric dichloride (HgCl{sub 2}) in human samples of salivary glands and lymphocytes to elucidate a possible role in tumor initiation. DNA migration due to single strand breaks, alkali labile sites and incomplete excision repair was quantified with the aid of the single cell microgel electrophoresis (Comet) assay. The concepts of Olive Tail Moment, percentage of DNA in the Tail and Tail Length were used as measures of DNA damage. To control for cytotoxic effects, the trypan blue exclusion test was applied. Human samples of the parotid salivary gland and lymphocytes of ten donors were exposed to HgCl{sub 2} concentrations from 1 to 50 {mu}M. N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) and dimethyl sulfoxide (DMSO) served as controls. Increasing dose-dependent DNA migration could be demonstrated after exposure to HgCl{sub 2} in cells of the salivary glands and lymphocytes. In both cell types a significant increase in DNA migration could be shown starting from HgCl{sub 2} concentrations of 5 {mu}M in comparison to the negative control. The viability of the cell systems was not affected except at the highest concentration (50 {mu}M) tested. These data indicate genotoxic effects of mercuric dichloride in human salivary glands and lymphocytes at concentrations not leading to cytotoxic effects or cell death. Consequently, a contributory role in oral salivary gland tumor initiation warrants further investigation. (orig.)

  14. Chromosome aberrations in human lymphocytes for investigation of individual radiosensitivity

    Zitzelsberger, H.; Bauchinger, M.

    2000-01-01

    Stable translocations and insertions which are not selected against during cell proliferation can be reliably scored by use of fluorescence in situ hybridisation (FISH) which allows painting of selected chromosomes along their entire length. This temporal persistence makes them particulary valuable for quantifying post human radiation exposures ('biodosimetry'). A disadvantage of this approach is that for routine use only a partial genome analysis can be performed which is mostly based on triple combinations of DNA probes for particular chromosomes. Translocation frequencies from partial genome analysis are often scaled-up to equal the full genome. Basic assumptions for such scaling are, that double strand breaks leading to translocations must be distributed randomly throughout the genome and no preferential interaction between particular pairs of chromosomes occurs. Thus, the probability of a particular chromosome being involved in an exchange is proportional to its DNA content. However, this is not always supported by experimental findings and may thus indicate a differential radiosensitivity of particular chromosomes. Translocation measurements in peripheral blood of different healthy donors irradiated in vitro with the same dose revealed also some evidence for the existence of interindividual differences in radiosensitivity. Similar findings have been already demonstrated after therapeutic irradiation of tumour patients. Consequences thereof may result for long-term retrospective biodosimetry. In order to provide reliable estimates of an individual's exposure to ionising radiation, the extent, distribution and dose-dependence of the observed variability has to be carefully examined in larger groups of persons and larger sets of calibration data. (orig.) [de

  15. T lymphocytes derived from human cord blood provide effective antitumor immunotherapy against a human tumor

    Kim Tae-Sik

    2011-06-01

    Full Text Available Abstract Background Although the graft-versus-tumor (GVT effect of donor-derived T cells after allogeneic hematopoietic stem cell transplantation has been used as an effective adoptive immunotherapy, the antitumor effects of cord blood (CB transplantation have not been well studied. Methods We established the animal model by transplantation of CB mononuclear cells and/or tumor cells into NOD/SCID mice. The presence of CB derived T cells in NOD/SCID mice or tumor tissues were determined by flow cytometric and immunohistochemical analysis. The anti-tumor effects of CB derived T cells against tumor was determined by tumor size and weight, and by the cytotoxicity assay and ELISPOT assay of T cells. Results We found dramatic tumor remission following transfer of CB mononuclear cells into NOD/SCID mice with human cervical tumors with a high infiltration of CD3+ T cells in tumors. NOD/SCID mice that receive neonatal CB transplants have reconstituted T cells with significant antitumor effects against human cervical and lung tumors, with a high infiltration of CD3+ T cells showing dramatic induction of apoptotic cell death. We also confirmed that T cells showed tumor specific antigen cytotoxicity in vitro. In adoptive transfer of CD3+ T cells into mice with pre-established tumors, we observed much higher antitumor effects of HPV-specific T cells by ELISPOT assays. Conclusions Our results show that CB derived T lymphocytes will be useful for novel immunotherapeutic candidate cells for therapy of several tumors in clinic.

  16. Biological effects of tritiated water in low concentration of human lymphocyte chromosome

    Tanaka, K.; Kamada, N.; Sawaeda, S.

    1992-01-01

    This study was undertaken to investigate the dose-response relationship of tritiated water (HTO) for chromosome aberration in the human lymphocytes, at low dose in vitro exposure ranging from 0.1-1 Gy. The Relative Biological Effectiveness values of HTO with respect to 60 Co gamma ray at a dose rate of 2 cGy/min(15 mCi/ml), at low dose range for the induction of dicentric and centric ring chromosomes were 2.7 in lymphocytes. Also lymphocytes were chronically exposed to HTO for 67 to 80 hrs at different lower dose rates (0.5 and 0.02 cGy/min). There was a 77% decrease in the yields of dicentrics and centric rings, at the dose rate of 0.02cGy/min of HTO, presenting a clear dose rate effect of HTO. The RBE value of HTO relative to 137 Cs gamma ray was 2.0 at the dose rate of 0.02cGy/min(0.15mCi/ml). This suggests that a higher dose rate of HTO exposure has a higher risk and a decrease of RBE value at low dose rate. These results provide useful information for the assessment of health risks in humans specially exposed to low concentration of HTO. (author). 6 refs., 2 figs

  17. Ultraviolet-induced DNA excision repair in human B and T lymphocytes. II

    Yew, F.F.-H.; Johnson, R.T.

    1979-01-01

    Despite their great sensitivity to ultraviolet light purified human B and T lymphocytes are capable of complete repair provided that the ultraviolet dose does not exceed 0.5 Jm -2 . Their capacity to repair, as measured by the restoration of DNA supercoiling in preparations of nucleoids, and their survival are significantly increased in the presence of deoxyribonucleosides. Certain agents which inhibit semi-conservative DNA synthesis (hydroxyurea, 1-β-D-arabino-furanosylcytosine (arafCyt) either stop or delay the repair process in lymphocytes. The effect of hydroxyurea is eventually overcome spontaneously, but changes in the sedimentation behaviour of ultraviolet-irradiated nucleoids caused by arafCyt can only be neutralized by addition of deoxycytidine. The effective inhibition of repair by arafCyt permits the detection of extremely small amounts of ultraviolet damage and also the estimation of when repair is complete. (Auth.)

  18. Improvement of techniques for the detection of radio-induced micronuclei in human blood lymphocytes

    Voisin, P.; Paillole, N.

    1995-12-31

    Scoring of micronuclei in cytokinesis-blocked peripheral human lymphocytes, after an accidental overexposure, seems an easier and faster alternative for biological dosimetry than conventional cytogenetics (dicentric chromosomes). Several variations of the cytokinesis-block micronucleus assay have been tested, in order to obtain a sufficient number of micronuclei in bi-nucleated cells by the shortest time possible for operational purposes. The methods differ in the use of hypotonic treatment as well as culture time (48 to 72 h), amount of blood and materials used. We have compared frequencies of bi-nucleated cells and micronuclei in normal lymphocytes and after {gamma}-({sup 60}Co) irradiation in vitro with {sup 60}Co for doses up to 6 Gy. Main results and the final choice of the technique are presented. (authors). 3 refs., 3 figs.

  19. Improvement of techniques for the detection of radio-induced micronuclei in human blood lymphocytes

    Voisin, P.; Paillole, N.

    1995-01-01

    Scoring of micronuclei in cytokinesis-blocked peripheral human lymphocytes, after an accidental overexposure, seems an easier and faster alternative for biological dosimetry than conventional cytogenetics (dicentric chromosomes). Several variations of the cytokinesis-block micronucleus assay have been tested, in order to obtain a sufficient number of micronuclei in bi-nucleated cells by the shortest time possible for operational purposes. The methods differ in the use of hypotonic treatment as well as culture time (48 to 72 h), amount of blood and materials used. We have compared frequencies of bi-nucleated cells and micronuclei in normal lymphocytes and after γ-( 60 Co) irradiation in vitro with 60 Co for doses up to 6 Gy. Main results and the final choice of the technique are presented. (authors). 3 refs., 3 figs

  20. X-ray induction of micronuclei in human lymphocyte subpopulations differentiated by immunoperoxidase staining

    Ban, Sadayuki; Nakano, Mimako; Cologne, J.B.

    1992-10-01

    In this report we sought to confirm the radiosensitivity of human peripheral blood lymphocyte subpopulations using a micronucleus assay. Mononucleated cells isolated from peripheral blood were irradiated with X rays. After being cultured for 3 days, cells were fixed and stained using the immunoperoxidase staining technique. Lymphocyte subpopulations were characterized by means of the monoclonal antibodies Leu4 (CD3), Leu2a (CD8), and Leu19 (CD56). Dose-response curves were obtained by scoring the number of micronuclei in binucleated cells that reacted with a specific antibody and were then stained. The dose response of CD8 + (suppressor/cytotoxic) cells was quite similar to that of CD3 + (pan T) cells. In comparison, CD56 + (natural killer) cells were significantly less sensitive, although scorable binucleated CD56 + cells made up less than 4 % of the total number of binucleated cells. (author)

  1. The cytogenetic effects of black tea and green tea on cultured human lymphocytes

    Halil Erhan Eroğlu

    2011-12-01

    Full Text Available In this study, the cytogenetic effects of black tea and green tea were determined in cultured peripheral blood lymphocytes. Results showed that black tea and green tea induced the mitotic and replication indexes and decreased micronuclei. But these data were not statistically significant for green tea. The effects of black tea on the micronucleus formation and mitotic index were statistically significant. The decrease in micronucleus counts indicated that black tea and green tea had considerable anticlastogenic and antigenotoxic effects as observed in vitro in human lymphocytes. Thus, it could be concluded that tea polyphenols protected the normal cells from genotoxic or carcinogenic agents, which indicated the therapeutic and antioxidative role of catechins, flavonoids or other tea compounds.

  2. Prophylactic role of some plants and phytochemicals against radio-genotoxicity in human lymphocytes

    Mohsen Cheki

    2016-01-01

    Full Text Available Genotoxicity in lymphocytes of cancer patients undergoing radiotherapy can lead to lymphocytopenia. Lymphocytopenia induced by radiotherapy is one of the most unfavorable prognostic biological markers in cancer patients, since it has been accepted to be associated with poor prognosis in terms of both survival time and response to cancer therapy. Therefore, reduction in lymphocytopenia may increase treatment efficiency. Research endeavors with synthetic radioprotectors in the past have met with little success primarily due to toxicity-related problems. These disadvantages have led to interest on the use of some plants and phytochemicals as radioprotector. The aim of this paper is to review protective role of some plants and phytochemicals against genotoxicity-induced by ionizing radiation in human blood lymphocytes. Therefore, current review may help the future researches to decrease lymphocytopenia in radiotherapeutic clinical trials.

  3. Lymphocyte trafficking and HIV infection of human lymphoid tissue in a rotating wall vessel bioreactor

    Margolis, L. B.; Fitzgerald, W.; Glushakova, S.; Hatfill, S.; Amichay, N.; Baibakov, B.; Zimmerberg, J.

    1997-01-01

    The pathogenesis of HIV infection involves a complex interplay between both the infected and noninfected cells of human lymphoid tissue, the release of free viral particles, the de novo infection of cells, and the recirculatory trafficking of peripheral blood lymphocytes. To develop an in vitro model for studying these various aspects of HIV pathogenesis we have utilized blocks of surgically excised human tonsils and a rotating wall vessel (RWV) cell culture system. Here we show that (1) fragments of the surgically excised human lymphoid tissue remain viable and retain their gross cytoarchitecture for at least 3 weeks when cultured in the RWV system; (2) such lymphoid tissue gradually shows a loss of both T and B cells to the surrounding growth medium; however, this cellular migration is reversible as demonstrated by repopulation of the tissue by labeled cells from the growth medium; (3) this cellular migration may be partially or completely inhibited by embedding the blocks of lymphoid tissue in either a collagen or agarose gel matrix; these embedded tissue blocks retain most of the basic elements of a normal lymphoid cytoarchitecture; and (4) both embedded and nonembedded RWV-cultured blocks of human lymphoid tissue are capable of productive infection by HIV-1 of at least three various strains of different tropism and phenotype, as shown by an increase in both p24 antigen levels and free virus in the culture medium, and by the demonstration of HIV-1 RNA-positive cells inside the tissue identified by in situ hybridization. It is therefore reasonable to suggest that gel-embedded and nonembedded blocks of human lymphoid tissue, cocultured with a suspension of tonsillar lymphocytes in an RWV culture system, constitute a useful model for simulating normal lymphocyte recirculatory traffic and provide a new tool for testing the various aspects of HIV pathogenesis.

  4. Novel human polyomaviruses, Merkel cell polyomavirus and human polyomavirus 9, in Japanese chronic lymphocytic leukemia cases

    Imajoh Masayuki

    2012-06-01

    Full Text Available Abstract Background Chronic lymphocytic leukemia (CLL is the rarest adult leukemia in Japan, whereas it is the most common leukemia in the Western world. Recent studies from the United States and Germany suggest a possible etiological association between Merkel cell polyomavirus (MCPyV and CLL, although no data have been reported from Eastern countries. To increase the volume of relevant data, this study investigated the prevalence and DNA loads of MCPyV and human polyomavirus 9 (HPyV9, another lymphotropic polyomavirus, in Japanese CLL cases. Findings We found that 9/27 CLL cases (33.3 % were positive for MCPyV using quantitative real-time polymerase chain reaction analysis. The viral DNA loads ranged from 0.000017 to 0.0012 copies per cell. All cases were negative for HPyV9. One MCPyV-positive CLL case was evaluated by mutational analysis of the large T (LT gene, which indicated the presence of wild-type MCPyV without a nucleotide deletion. DNA sequence analysis of the entire small T (ST gene and the partial LT gene revealed that a Japanese MCPyV isolate, designated CLL-JK, had two nucleotide gaps when compared with the reference sequence of the North American isolate MCC350. Conclusions This study provides the first evidence that MCPyV is present in a subset of Japanese CLL cases with low viral DNA loads. MCPyV and HPyV9 are unlikely to contribute directly to the development of CLL in the majority of Japanese cases. MCPyV isolated from the Japanese CLL cases may constitute an Asian group and its pathogenicity needs to be clarified in future studies.

  5. Anti-mutagenic and Pro-apoptotic Effects of Apigenin on Human Chronic Lymphocytic Leukemia Cells

    Mehrdad Hashemi

    2010-09-01

    Full Text Available "nDiet can play a vital role in cancer prevention. Nowadays the scientists are looking for food materials which can potentially prevent the cancer occurrence. The purpose of this research is to examine anti-mutagenic and apoptotic effects of apigenin in human lymphoma cells. In present study human chronic lymphocytic leukemia (Eheb cell line were cultured in RPMI 1640 (Sigma, supplemented with 10% fetal calf serum, penicillin-streptomycin, L-glutamine and incubated at 37 ºC for 2 days. In addition cancer cell line was treated by and apigenin and cellular vital capacity was determined by MTT assay. Then effect of apigenin in human lymphoma B cells was examined by flow cytometry techniques. The apigenin was subsequently evaluated in terms of anti-mutagenic properties by a standard reverse mutation assay (Ames test. This was performed with histidine auxotroph strain of Salmonella typhimurium (TA100. Thus, it requires histidine from a foreign supply to ensure its growth. The aforementioned strain gives rise to reverted colonies when expose to sodium azide as a carcinogen substance. During MTT assay, human chronic lymphocytic leukemia revealed to have a meaningful cell death when compared with controls (P<0.01 Apoptosis was induced suitably after 48 hours by flow cytometry assay. In Ames test apigenin prevented the reverted mutations and the hindrance percent of apigenin was 98.17%.These results have revealed apigenin induced apoptosis in human lymphoma B cells in vitro.

  6. Recognition of lyso-phospholipids by human natural killer T lymphocytes.

    Lisa M Fox

    2009-10-01

    Full Text Available Natural killer T (NKT cells are a subset of T lymphocytes with potent immunoregulatory properties. Recognition of self-antigens presented by CD1d molecules is an important route of NKT cell activation; however, the molecular identity of specific autoantigens that stimulate human NKT cells remains unclear. Here, we have analyzed human NKT cell recognition of CD1d cellular ligands. The most clearly antigenic species was lyso-phosphatidylcholine (LPC. Diacylated phosphatidylcholine and lyso-phosphoglycerols differing in the chemistry of the head group stimulated only weak responses from human NKT cells. However, lyso-sphingomyelin, which shares the phosphocholine head group of LPC, also activated NKT cells. Antigen-presenting cells pulsed with LPC were capable of stimulating increased cytokine responses by NKT cell clones and by freshly isolated peripheral blood lymphocytes. These results demonstrate that human NKT cells recognize cholinated lyso-phospholipids as antigens presented by CD1d. Since these lyso-phospholipids serve as lipid messengers in normal physiological processes and are present at elevated levels during inflammatory responses, these findings point to a novel link between NKT cells and cellular signaling pathways that are associated with human disease pathophysiology.

  7. Genotoxicity of triiodothyronine: Effects on Salmonella typhimurium TA100 and human lymphocytes in vitro

    Bošnjak-Neumüller Jasna

    2017-01-01

    Full Text Available There is increasing evidence that substances which are normally present in human or animal bodies may, under the certain circumstances, exhibit deleterious effects on genetic material, therefore acting as endogenous mutagenic agents. Since hormones represent one of the best studied endogenous mutagens, some research focused on the possible role of thyroid hormone in mutagenesis and carcinogenesis. Indeed, thyroid hormones accelerate aerobic metabolism and production of reactive oxygen species (ROS and, therefore, may exhibit mutagenic effects in various test systems on mammalian cells. However, possible mutagenic effects on prokaryotic DNA has not been investigated so far. Hence, the aim of this research was to compare the sensitivity of TA 100 Salmonella typhimurium with and without metabolic activation with S9 fraction, and human lymphocytes to possible genotoxic effects of triiodothyronine (T3. Therefore, we used the reverse mutation assay on S. typhimurium (Ames test and in vitro Comet assay in isolated peripheral blood human lymphocytes. In both tests-systems a broad spectrum of T3 concentrations was applied. The obtained results showed absence of genotoxic effects of T3 in bacterial reverse mutation assay and very profound genotoxic effects in human lymphocytes at concentrations higher than 15 μM. We only observed cytotoxic effects in bacterial system at very high T3 concentrations (300 and 500 μM. In conclusion, T3 was unable to increase the level of reverse mutations in Ames test both with and without S9 mix. Therefore, it seems that ROS production in mitochondria may be the primary cause of DNA damage caused by T3 in mammalian cells. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. III46002

  8. Lymphocyte subsets in human immunodeficiency virus-unexposed Brazilian individuals from birth to adulthood

    Maria Isabel de Moraes-Pinto

    2014-12-01

    Full Text Available Ethnic origin, genetics, gender and environmental factors have been shown to influence some immunologic indices, so that development of reference values for populations of different backgrounds may be necessary. We have determined the distribution of lymphocyte subsets in healthy Brazilian individuals from birth to adulthood. Lymphocyte subsets were determined using four-colour cytometry in a cross-sectional study of 463 human immunodeficiency virus-unexposed children and adults from birth through 49 years of age. Lymphocyte subsets varied according to age, as previously observed in other studies. However, total CD4+ T cell numbers were lower than what was described in the Pediatric AIDS Clinical Trials Group P1009 (PACTG P1009, which assessed an American population of predominantly African and Hispanic backgrounds until the 12-18 year age range, when values were comparable. Naïve percentages and absolute values of CD8+ T cells, as assessed by CD45RA expression, were also lower than the PACTG P1009 data for all analysed age ranges. CD38 expression on both CD4+ and CD8+ T cells was lower than the PACTG P1009 values, with a widening gap between the two studies at older age ranges. Different patterns of cell differentiation seem to occur in different settings and may have characteristic expression within each population.

  9. Visualization of antigen-specific human cytotoxic T lymphocytes labeled with superparamagnetic iron-oxide particles

    Beer, Ambros J. [Technical University of Munich (TUM), Department of Nuclear Medicine, Klinikum rechts der Isar, Munich (Germany); Holzapfel, Konstantin; Settles, Marcus; Rummeny, Ernst J. [Technical University of Munich, Department of Radiology, Klinikum rechts der Isar, Munich (Germany); Neudorfer, Juliana; Kroenig, Holger; Peschel, Christian; Bernhard, Helga [TUM, Munich, Department of Hematology/Oncology, Klinikum rechts der Isar, Munich (Germany); Piontek, Guido; Schlegel, Juergen [TUM, Munich, Division of Neuropathology, Institute of Pathology, Klinikum rechts der Isar, Munich (Germany)

    2008-06-15

    New technologies are needed to characterize the migration and survival of antigen-specific T cells in vivo. In this study, we developed a novel technique for the labeling of human cytotoxic T lymphocytes with superparamagnetic iron-oxide particles and the subsequent depiction with a conventional 1.5-T magnetic resonance scanner. Antigen-specific CD8{sup +} T lymphocytes were labeled with ferucarbotran by lipofection. The uptake of ferucarbotran was confirmed by immunofluorescence microscopy using a dextran-specific antibody, and the intracellular enrichment of iron was measured by atomic absorption spectrometry. The imaging of T cells was performed by magnetic resonance on day 0, 2, 7 and 14 after the labeling procedure. On day 0 and 2 post labeling, a pronounced shortening of T2*-relaxation times was observed, which diminished after 7 days and was not detectable anymore after 14 days, probably due to the retained mitotic activity of the labeled T cells. Of importance, the antigen-specific cytolytic activity of the T cells was preserved following ferucarbotran labeling. Efficient ferucarbotran labeling of functionally active T lymphocytes and their detection by magnetic resonance imaging allows the in vivo monitoring of T cells and, subsequently, will impact the further development of T cell-based therapies. (orig.)

  10. Visualization of antigen-specific human cytotoxic T lymphocytes labeled with superparamagnetic iron-oxide particles

    Beer, Ambros J.; Holzapfel, Konstantin; Settles, Marcus; Rummeny, Ernst J.; Neudorfer, Juliana; Kroenig, Holger; Peschel, Christian; Bernhard, Helga; Piontek, Guido; Schlegel, Juergen

    2008-01-01

    New technologies are needed to characterize the migration and survival of antigen-specific T cells in vivo. In this study, we developed a novel technique for the labeling of human cytotoxic T lymphocytes with superparamagnetic iron-oxide particles and the subsequent depiction with a conventional 1.5-T magnetic resonance scanner. Antigen-specific CD8 + T lymphocytes were labeled with ferucarbotran by lipofection. The uptake of ferucarbotran was confirmed by immunofluorescence microscopy using a dextran-specific antibody, and the intracellular enrichment of iron was measured by atomic absorption spectrometry. The imaging of T cells was performed by magnetic resonance on day 0, 2, 7 and 14 after the labeling procedure. On day 0 and 2 post labeling, a pronounced shortening of T2*-relaxation times was observed, which diminished after 7 days and was not detectable anymore after 14 days, probably due to the retained mitotic activity of the labeled T cells. Of importance, the antigen-specific cytolytic activity of the T cells was preserved following ferucarbotran labeling. Efficient ferucarbotran labeling of functionally active T lymphocytes and their detection by magnetic resonance imaging allows the in vivo monitoring of T cells and, subsequently, will impact the further development of T cell-based therapies. (orig.)

  11. Stable-isotope dilution GC-MS approach for nitrite quantification in human whole blood, erythrocytes, and plasma using pentafluorobenzyl bromide derivatization: nitrite distribution in human blood.

    Schwarz, Alexandra; Modun, Darko; Heusser, Karsten; Tank, Jens; Gutzki, Frank-Mathias; Mitschke, Anja; Jordan, Jens; Tsikas, Dimitrios

    2011-05-15

    Previously, we reported on the usefulness of pentafluorobenzyl bromide (PFB-Br) for the simultaneous derivatization and quantitative determination of nitrite and nitrate in various biological fluids by GC-MS using their (15)N-labelled analogues as internal standards. As nitrite may be distributed unevenly in plasma and blood cells, its quantification in whole blood rather than in plasma or serum may be the most appropriate approach to determine nitrite concentration in the circulation. So far, GC-MS methods based on PFB-Br derivatization failed to measure nitrite in whole blood and erythrocytes because of rapid nitrite loss by oxidation and other unknown reactions during derivatization. The present article reports optimized and validated procedures for sample preparation and nitrite derivatization which allow for reliable quantification of nitrite in human whole blood and erythrocytes. Essential measures for stabilizing nitrite in these samples include sample cooling (0-4°C), hemoglobin (Hb) removal by precipitation with acetone and short derivatization of the Hb-free supernatant (5 min, 50°C). Potassium ferricyanide (K(3)Fe(CN)(6)) is useful in preventing Hb-caused nitrite loss, however, this chemical is not absolutely required in the present method. Our results show that accurate GC-MS quantification of nitrite as PFB derivative is feasible virtually in every biological matrix with similar accuracy and precision. In EDTA-anticoagulated venous blood of 10 healthy young volunteers, endogenous nitrite concentration was measured to be 486±280 nM in whole blood, 672±496 nM in plasma (C(P)), and 620±350 nM in erythrocytes (C(E)). The C(E)-to-C(P) ratio was 0.993±0.188 indicating almost even distribution of endogenous nitrite between plasma and erythrocytes. By contrast, the major fraction of nitrite added to whole blood remained in plasma. The present GC-MS method is useful to investigate distribution and metabolism of endogenous and exogenous nitrite in blood

  12. Cytological and cytochemical effects of sodium benzoate and gamma irradiation on human peripheral lymphocytes

    Mohamed, N.A.F.

    1981-01-01

    In vitro studies of human peripheral lymphocytes were conducted to elucidate and compare the effects of a suspected chemical clastogen, sodium benzoate, widely used in the food industry as an antimicrobial food additive, to that of a well-known physical mutagen, gamma rays. Blood from ten normal donors, five males and five females, was collected and treated with various doses of the two agents independently and in combination during G 0 or G 1 phase. Induction of structural chromosomal aberrations, sister chromatid exchanges (SCEs) and unscheduled DNA synthesis were used as parameters to monitor the effects of the two agents. Sodium benzoate at the same concentrations used in the food industry (0.05% and 0.10%) caused inhibition of mitosis and induced chromatid-type aberrations (gaps and breaks). The frequency of aberrations increased as the concentration of sodium benzoate increased. No increase in SCEs over the control level was observed as either concentration tested. The relative amount of DNA damage inflicted in the treated lymphocytes estimated as 3 H-tritiated thymidine incorporation (unscheduled DNA synthesis) was highly significant. In contrast, blood irradiated with 300, 600, or 900 rad 60 Co gamma rays produced chromatid and chromosome aberrations in cultured lymphocytes, dicentrics being the most frequent exchange event. The aberration yield was found to be dose-dependent and to fit the quadratic model. Unscheduled DNA synthesis as measured by lymphocyte 3 H-TdR incorporation following gamma irradiation was highly significantly increased with the largest uptake occurring during the first hour of incubation. The combined treatment of gamma irradiation plus 0.05% sodium benzoate did not increase the aberration frequencies over the independent irradiation treatments and had no effect on SCEs frequencies

  13. Anti-mutagenic and Pro-apoptotic Effects of Apigenin on Human Chronic Lymphocytic Leukemia Cells

    Mehrdad Hashemi

    2010-10-01

    Full Text Available Diet can play a vital role in cancer prevention. Nowadays the scientists are looking for food materials which can potentially prevent the cancer occurrence. The purpose of this research is to examine anti-mutagenic and apoptotic effects of apigenin in human lymphoma cells. In present study human chronic lymphocytic leukemia (Eheb cell line were cultured in RPMI 1640 (Sigma, supplemented with 10% fetal calf serum, penicillin-streptomycin, L-glutamine and incubated at 37 ºC for 2 days. In addition cancer cell line was treated by and apigenin and cellular vital capacity was determined by MTT assay. Then effect of apigenin in human lymphoma B cells was examined by flow cytometry techniques. The apigenin was subsequently evaluated in terms of anti-mutagenic properties by a standard reverse mutation assay (Ames test. This was performed with histidine auxotroph strain of Salmonella typhimurium (TA100. Thus, it requires histidine from a foreign supply to ensure its growth. The aforementioned strain gives rise to reverted colonies when expose to sodium azide as a carcinogen substance. During MTT assay, human chronic lymphocytic leukemia revealed to have a meaningful cell death when compared with controls (P

  14. In vitro cytotoxic, genotoxic and antioxidant/oxidant effects of guaiazulene on human lymphocytes

    Başak Toğar

    2015-02-01

    Full Text Available The aim of this study was to evaluate for the cytotoxicity, genotoxicity and antioxidant/oxidant activity of GYZ on human peripheral blood lymphocytes (PBLs. Guaiazulene (GYZ was added into culture tubes at various concentrations (0-400 µg/mL-1. Cytotoxicity against the human lymphocytes cultures was examined by lactate dehydrogenase (LDH release assay. The proliferative response was estimated by 3-(4,5-dimethylthiazol-2-yl-2,5-diphenyl tetrazolium bromide (MTT assay. Antioxidant/oxidant activity was evaluated by measuring the total oxidant status (TOS and total antioxidant capacity (TAC levels. Micronucleus (MN and chromosomal aberration (CA tests were used in genotoxicity studies. The results showed that GYZ caused cytotoxicity in the PBLs at high concentrations, but TOS level were not affected, while the level of TAC was significantly increased. GYZ also did not induce chromosomal aberrations when compared to that of the control group. Results this study clearly revealed that GYZ was not genotoxic and also increased the capacity of the antioxidant in the culture of human PBL cells. This report is first report on the impact of GYZ on human PBL cells.

  15. Cytotoxicity and genotoxicity of clothianidin in human lymphocytes with or without metabolic activation system.

    Atlı Şekeroğlu, Zülal; Şekeroğlu, Vedat; Uçgun, Ebru; Kontaş Yedier, Seval; Aydın, Birsen

    2018-02-26

    Clothianidin (CHN) is a broad-spectrum neonicotinoid insecticide. Limited studies have been carried out on the cytotoxic and genotoxic effects of both CHN using different genotoxicity tests in human cells with or without human metabolic activation system (S9 mix). Therefore, the aim of this study is to investigate the cytotoxic and genotoxic effects of CHN and its metabolites on human lymphocyte cultures with or without S9 mix using chromosomal aberration (CA) and micronucleus (MN) tests. The cultures were treated with 25, 50, and 100 µg/ml of CHN in the presence (3 h treatment) and absence (48 h treatment) of S9 mix. Dimethyl sulfoxide (DMSO) was used as a solvent control. CHN showed cytotoxic and genotoxic effects due to significant decreases in mitotic index (MI) and nuclear division index (NDI), and significant increases in the CAs, aberrant cells, and MN formation in the absence of S9 mix when compared with solvent control. However, CHN did not significantly induce cytotoxicity and genotoxicity in the presence of S9 mix. Our results indicated that CHN has cytotoxic, cytostatic, and genotoxic potential on human peripheral blood lymphocyte cultures, but not its metabolites under the experimental conditions.

  16. Toxicological Implications and Inflammatory Response in Human Lymphocytes Challenged with Oxytetracycline.

    Di Cerbo, A; Palatucci, A T; Rubino, V; Centenaro, S; Giovazzino, A; Fraccaroli, E; Cortese, L; Ruggiero, G; Guidetti, G; Canello, S; Terrazzano, G

    2016-04-01

    Antibiotics are widely used in zoo technical and veterinary practices as feed supplementation to ensure wellness of farmed animals and livestock. Several evidences have been suggesting both the toxic role for tetracyclines, particularly for oxytetracycline (OTC). This potential toxicity appears of great relevance for human nutrition and for domestic animals. This study aimed to extend the evaluation of such toxicity. The biologic impact of the drug was assessed by evaluating the proinflammatory effect of OTC and their bone residues on cytokine secretion by in vitro human peripheral blood lymphocytes. Our results showed that both OTC and OTC-bone residues significantly induced the T lymphocyte and non-T cell secretion of interferon (IFN)-γ, as cytokine involved in inflammatory responses in humans as well as in animals. These results may suggest a possible implication for new potential human and animal health risks depending on the entry of tetracyclines in the food-processing chain. © 2015 The Authors Journal of Biochemical and Molecular Toxicology Published Wiley Periodicals, Inc.

  17. Culture of normal human blood cells in a diffusion chamber system II. Lymphocyte and plasma cell kinetics

    Chikkappa, G.; Carsten, A.L.; Chanana, A.D.; Cronkite, E.P.

    1979-01-01

    Normal human blood leukocytes were cultured in Millipore diffusion chambers implanted into the peritoneal cavities of irradiated mice. The evaluation of survival and proliferation kinetics of cells in lymphyocytic series suggested that the lymphoid cells are formed from transition of small and/or large lymphocytes, and the lymphoblasts from the lymphoid cells. There was also evidence indicating that some of the cells in these two compartments are formed by proliferation. The evaluation of plasmacytic series suggested that the plasma cells are formed from plasmacytoid-lymphocytes by transition, and the latter from the transition of lymphocytes. In addition, relatively a small fraction of cells in these two compartments are formed by proliferation. mature plasma cells do not and immature plasma cells do proliferate. Estimation of magnitude of plasma cells formed in the cultures at day 18 indicated that at least one plasma cell is formed for every 6 normal human blood lymphocytes introduced into the culture

  18. Impact of the New Generation Reconstituted Surfactant CHF5633 on Human CD4+ Lymphocytes.

    Markus Fehrholz

    Full Text Available Natural surfactant preparations, commonly isolated from porcine or bovine lungs, are used to treat respiratory distress syndrome in preterm infants. Besides biophysical effectiveness, several studies have documented additional immunomodulatory properties. Within the near future, synthetic surfactant preparations may be a promising alternative. CHF5633 is a new generation reconstituted synthetic surfactant preparation with defined composition, containing dipalmitoyl-phosphatidylcholine, palmitoyl-oleoyl-phosphatidylglycerol and synthetic analogs of surfactant protein (SP- B and SP-C. While its biophysical effectiveness has been demonstrated in vitro and in vivo, possible immunomodulatory abilities are currently unknown.The aim of the current study was to define a potential impact of CHF5633 and its single components on pro- and anti-inflammatory cytokine responses in human CD4+ lymphocytes.Purified human CD4+ T cells were activated using anti CD3/CD28 antibodies and exposed to CHF5633, its components, or to the well-known animal-derived surfactant Poractant alfa (Curosurf®. Proliferative response and cell viability were assessed using flow cytometry and a methylthiazolyldiphenyltetrazolium bromide colorimetric assay. The mRNA expression of IFNγ, IL-2, IL-17A, IL-22, IL-4, and IL-10 was measured by quantitative PCR, while intracellular protein expression was assessed by means of flow cytometry.Neither CHF5633 nor any of its phospholipid components with or without SP-B or SP-C analogs had any influence on proliferative ability and viability of CD4+ lymphocytes under the given conditions. IFNγ, IL-2, IL-17A, IL-22, IL-4, and IL-10 mRNA as well as IFNγ, IL-2, IL-4 and IL-10 protein levels were unaffected in both non-activated and activated CD4+ lymphocytes after exposure to CHF5633 or its constituents compared to non-exposed controls. However, in comparison to Curosurf®, expression levels of anti-inflammatory IL-4 and IL-10 mRNA were

  19. The uptake kinetics and immunotoxic effects of microcystin-LR in human and chicken peripheral blood lymphocytes in vitro

    Lankoff, Anna; Carmichael, Wayne W.; Grasman, Keith A.; Yuan, Moucun

    2004-01-01

    Microcystin-LR is a cyanobacterial heptapeptide that presents acute and chronic hazards to animal and human health. We investigated the influence of this toxin on human and chicken immune system modulation in vitro. Peripheral blood lymphocytes were treated with microcystin-LR at environmentally relevant doses of 1, 10 and 25 μg/ml for 12, 24, 48, 72 h (for proliferation assay cells were treated for 72 h). T-cell and B-cell proliferation as well as apoptosis and necrosis were determined in human and chicken samples. IL-2 and IL-6 production by human lymphocytes also was measured. In addition, uptake kinetics of microcystin-LR into human and chicken peripheral blood lymphocytes were calculated by Liquid Chromatography (LS) /Mass Spectrometry (MS) analysis. At the highest dose microcystin-LR decreased T-cell proliferation and all doses of microcystin-LR inhibited B-cell proliferation. The frequency of apoptotic and necrotic cells increased in a dose and time-dependent manner. Human lymphocytes responded to stimulation with microcystin-LR by increased production of IL-6 and decreased production of IL-2. Human lymphocytes were able to uptake from 0.014 to 1.663 μg/ml and chicken lymphocytes from 0.035 to 1.733 μg/ml of the microcystin-LR added to the cultures, depending on the treatment time and dose. In conclusion, microcystin-LR acted as an immunomodulator in cytokine production and down-regulated lymphocyte functions by induction of apoptosis and necrosis. However, further studies dealing with the influence of microcystin-LR on expression cytokine genes and transcription factors are necessary to confirm these hypotheses

  20. Oxcarbazepine-induced cytotoxicity and genotoxicity in human lymphocyte cultures with or without metabolic activation.

    Atlı Şekeroğlu, Zülal; Kefelioğlu, Haluk; Kontaş Yedier, Seval; Şekeroğlu, Vedat; Delmecioğlu, Berrin

    2017-03-01

    There has been considerable debate about the relationship between epilepsy and cancer. Oxcarbazepine (OXC) is used for treating certain types of seizures in patients with epilepsy. There have been no detailed investigations about genotoxicity of OXC and its metabolites. Therefore, the aim of this study is to investigate the cytotoxic and genotoxic effects of OXC and its metabolites on cultured human lymphocytes. The cytotoxicity and genotoxicity of OXC on human peripheral blood lymphocytes were examined in vitro by sister chromatid exchange (SCE), chromosomal aberration (CA) and micronucleus (MN) tests. Cultures were treated with 125, 250 and 500 μg/ml of OXC in the presence (3 h treatment) and absence (24 h and 48 h treatment) of a metabolic activator (S9 mix). Dimethyl sulfoxide (DMSO) was used as a solvent control. OXC showed cytotoxic activities due to significant decreases in mitotic index (MI), proliferation index (PI) and nuclear division index (NDI) in the absence of S9 mix when compared with solvent control. Metabolites of OXC also significantly reduced MI and PI in cultures with S9 mix. OXC significantly increased the CAs, aberrant cells, SCE and MN values in the presence and absence of S9 mix. Our results indicated that both OXC and its metabolites have cytotoxic, cytostatic and genotoxic potential on human peripheral blood lymphocyte cultures under the experimental conditions. Further studies are necessary to elucidate the relationship between cytotoxic, cytostatic and genotoxic effects, and to make a possible risk assessment in patients receiving therapy with this drug.

  1. Automatic analysis of the micronucleus test in primary human lymphocytes using image analysis.

    Frieauff, W; Martus, H J; Suter, W; Elhajouji, A

    2013-01-01

    The in vitro micronucleus test (MNT) is a well-established test for early screening of new chemical entities in industrial toxicology. For assessing the clastogenic or aneugenic potential of a test compound, micronucleus induction in cells has been shown repeatedly to be a sensitive and a specific parameter. Various automated systems to replace the tedious and time-consuming visual slide analysis procedure as well as flow cytometric approaches have been discussed. The ROBIAS (Robotic Image Analysis System) for both automatic cytotoxicity assessment and micronucleus detection in human lymphocytes was developed at Novartis where the assay has been used to validate positive results obtained in the MNT in TK6 cells, which serves as the primary screening system for genotoxicity profiling in early drug development. In addition, the in vitro MNT has become an accepted alternative to support clinical studies and will be used for regulatory purposes as well. The comparison of visual with automatic analysis results showed a high degree of concordance for 25 independent experiments conducted for the profiling of 12 compounds. For concentration series of cyclophosphamide and carbendazim, a very good correlation between automatic and visual analysis by two examiners could be established, both for the relative division index used as cytotoxicity parameter, as well as for micronuclei scoring in mono- and binucleated cells. Generally, false-positive micronucleus decisions could be controlled by fast and simple relocation of the automatically detected patterns. The possibility to analyse 24 slides within 65h by automatic analysis over the weekend and the high reproducibility of the results make automatic image processing a powerful tool for the micronucleus analysis in primary human lymphocytes. The automated slide analysis for the MNT in human lymphocytes complements the portfolio of image analysis applications on ROBIAS which is supporting various assays at Novartis.

  2. Towards a multiscale description of microvascular flow regulation: O2-dependent release of ATP from human erythrocytes and the distribution of ATP in capillary networks

    Daniel eGoldman

    2012-07-01

    Full Text Available Integration of the numerous mechanisms that have been suggested to contribute to optimization of O2 supply to meet O2 need in skeletal muscle requires a systems biology approach which permits quantification of these physiological processes over a wide range of length scales. Here we describe two individual computational models based on in vivo and in vitro studies which, when incorporated into a single robust multiscale model, will provide information on the role of erythrocyte-released ATP in perfusion distribution in skeletal muscle under both physiological and pathophysiological conditions. Healthy human erythrocytes exposed to low O2 tension release ATP via a well characterized signaling pathway requiring activation of the G-protein, Gi, and adenylyl cyclase leading to increases in cAMP. This cAMP then activates PKA and subsequently CFTR culminating in ATP release via pannexin 1. A critical control point in this pathway is the level of cAMP which is regulated by pathway-specific phosphodiesterases. Using time constants (~100ms that are consistent with measured erythrocyte ATP release, we have constructed a dynamic model of this pathway. The model predicts levels of ATP release consistent with measurements obtained over a wide range of hemoglobin O2 saturations (sO2. The model further predicts how insulin, at concentrations found in prediabetes, enhances the activity of PDE3 and reduces intracellular cAMP levels leading to decreased low O2-induced ATP release from erythrocytes. The second model, which couples O2 and ATP transport in capillary networks, shows how intravascular ATP and the resulting conducted vasodilation are affected by local sO2, convection and ATP degradation. This model also predicts network-level effects of decreased ATP release resulting from elevated insulin levels. Taken together, these models lay the groundwork for investigating the systems biology of the regulation of microvascular perfusion distribution by

  3. C(60 fullerene prevents genotoxic effects of doxorubicin in human lymphocytes in vitro

    K. S. Afanasieva

    2015-02-01

    Full Text Available The self-ordering of C60 fullerene, doxorubicin and their mixture precipitated from aqueous solutions was investigated using atomic-force microscopy. The results suggest the complexation between the two compounds. The genotoxicity of doxorubicin in complex with C60 fullerene (С60+Dox was evaluated in vitro with comet assay using human lymphocytes. The obtained results show that the C60 fullerene prevents the toxic effect of Dox in normal cells and, thus, С60+Dox complex might be proposed for biomedical application.

  4. A schedule to demonstrate radiation-induced sister chromatid exchanges in human lymphocytes

    Chaudhuri, J.P.

    1982-01-01

    The reciprocal interchange between the chromatids of a chromosome, termed sister chromatid exchange (SCE), is considered to be one of the most sensitive and accurate cytogenetic parameters and respond to toxic chemicals at very low doses. But the response of SCE to ionizing radiation is very poor. Human lymphocytes fail to give SCE response when irradiated at G 0 . Probably the primary lesions induced at G 0 do not remain available long enough to find expression as SCEs. Based on this assumption a schedule was developed using caffeine to demonstrate radiation induced SCEs. Following this schedule a dose-dependent increase in the frequency of radiation induced SCEs has been observed. (orig.)

  5. Protective effect of red wine on the frequency of micronuclei in human lymphocytes irradiated in vitro

    Stankovic, M.; Joksic, G.

    2000-01-01

    The present investigation was undertaken to study the effect of red wines 'Cabernet Sauvignon' on the micronuclei formation in human lymphocytes. Blood samples of healthy volunteers were irratiated in vitro using 60 Co as a source of radiation, dose of 2Gy. Irradiated samples, as well as unirradiated controls, were treated with concentrations of red wine ranged from 100-500 ml/2x106 cells. Obtained results demonstrated significant decrease of the micronuclei frequency (t=9.14; p0.05) in treated samples versus untreated controls. The results of our study demonstrated radioprotective effect of red wine

  6. Discriminating the hemolytic risk of blood type A plasmas using the complement hemolysis using human erythrocytes (CHUHE) assay.

    Cunnion, Kenji M; Hair, Pamela S; Krishna, Neel K; Sass, Megan A; Enos, Clinton W; Whitley, Pamela H; Maes, Lanne Y; Goldberg, Corinne L

    2017-03-01

    The agglutination-based cross-matching method is sensitive for antibody binding to red blood cells but is only partially predictive of complement-mediated hemolysis, which is important in many acute hemolytic transfusion reactions. Here, we describe complement hemolysis using human erythrocytes (CHUHE) assays that directly evaluate complement-mediated hemolysis between individual serum-plasma and red blood cell combinations. The CHUHE assay is used to evaluate correlations between agglutination titers and complement-mediated hemolysis as well as the hemolytic potential of plasma from type A blood donors. Plasma or serum from each type A blood donor was incubated with AB or B red blood cells in the CHUHE assay and measured for free hemoglobin release. CHUHE assays for serum or plasma demonstrate a wide, dynamic range and high sensitivity for complement-mediated hemolysis for individual serum/plasma and red blood cell combinations. CHUHE results suggest that agglutination assays alone are only moderately predictive of complement-mediated hemolysis. CHUHE results also suggest that plasma from particular type A blood donors produce minimal complement-mediated hemolysis, whereas plasma from other type A blood donors produce moderate to high-level complement-mediated hemolysis, depending on the red blood cell donor. The current results indicate that the CHUHE assay can be used to assess complement-mediated hemolysis for plasma or serum from a type A blood donor, providing additional risk discrimination over agglutination titers alone. © 2016 AABB.

  7. Radiation-induced structural changes in membrane proteins of human erythrocytes and ghosts and the relation to cellular morphology

    Schuurhuis, G.J.; Hommes, J.; Vos, J.; Molenaar, I.; Konings, A.W.T. (Rijksuniversiteit Groningen (Netherlands))

    1984-02-01

    Isolated human erythrocytes and ghosts were irradiated with X-rays under different experimental conditions and the effect examined with regard to the structure of membrane proteins and morphology of whole cells and ghosts. From sodium dodecyl sulphate/polyacrylamide gel electrophoresis it is concluded that spectrin (band 1 and 2) is the most radiosensitive of the membrane proteins examined. X-irradiation of cells and ghosts induced covalent cross-linking of a small fraction of membrane proteins. In the protein aggregates thus formed spectrin was found to be the major component. Molecular disulphide (-SS-) bridges seemed to account for part of the cross-links observed. Some nondisulphide cross-links were found, especially when ghosts were irradiated. Significant amounts of spectrin aggregates were formed during post-irradiation incubation at 37/sup 0/C but not at 4/sup 0/C. In the intact cell a transformation in shape from discocyte to echinocyte accompanied the process of post-irradiation spectrin aggregation. The characteristics of both processes, such as their reversibility with adenosine, point to a metabolic involvement. It is shown that there is no causal relationship between the two phenomena observed. Possible causes of the post-irradiation effects and the parallelism with similar processes in non-irradiated metabolically depleted cells are discussed.

  8. Radiation-induced structural changes in membrane proteins of human erythrocytes and ghosts and the relation to cellular morphology

    Schuurhuis, G.J.; Hommes, J.; Vos, J.; Molenaar, I.; Konings, A.W.T.

    1984-01-01

    Isolated human erythrocytes and ghosts were irradiated with X-rays under different experimental conditions and the effect examined with regard to the structure of membrane proteins and morphology of whole cells and ghosts. From sodium dodecyl sulphate/polyacrylamide gel electrophoresis it is concluded that spectrin (band 1 and 2) is the most radiosensitive of the membrane proteins examined. X-irradiation of cells and ghosts induced covalent cross-linking of a small fraction of membrane proteins. In the protein aggregates thus formed spectrin was found to be the major component. Molecular disulphide (-SS-) bridges seemed to account for part of the cross-links observed. Some nondisulphide cross-links were found, especially when ghosts were irradiated. Significant amounts of spectrin aggregates were formed during post-irradiation incubation at 37 0 C but not at 4 0 C. In the intact cell a transformation in shape from discocyte to echinocyte accompanied the process of post-irradiation spectrin aggregation. The characteristics of both processes, such as their reversibility with adenosine, point to a metabolic involvement. It is shown that there is no causal relationship between the two phenomena observed. Possible causes of the post-irradiation effects and the parallelism with similar processes in non-irradiated metabolically depleted cells are discussed. (author)

  9. Pre- and post-treatment effect of physostigmine on soman-inhibited human erythrocyte and muscle acetylcholinesterase in vitro

    Herkert, N.M.; Schulz, S.; Wille, T.; Thiermann, H.; Hatz, R.A.; Worek, F.

    2011-01-01

    Standard treatment of organophosphorus (OP) poisoning includes administration of an antimuscarinic (e.g., atropine) and of an oxime-based reactivator. However, successful oxime treatment in soman poisoning is limited due to rapid aging of phosphylated acetylcholinesterase (AChE). Hence, the inability of standard treatment procedures to counteract the effects of soman poisoning resulted in the search for alternative strategies. Recently, results of an in vivo guinea pig study indicated a therapeutic effect of physostigmine given after soman. The present study was performed to investigate a possible pre- and post-treatment effect of physostigmine on soman-inhibited human AChE given at different time intervals before or after perfusion with soman by using a well-established dynamically working in vitro model for real-time analysis of erythrocyte and muscle AChE. The major findings were that prophylactic physostigmine prevented complete inhibition of AChE by soman and resulted in partial spontaneous recovery of the enzyme by decarbamylation. Physostigmine given as post-treatment resulted in a time-dependent reduction of the protection from soman inhibition and recovery of AChE. Hence, these date indicate that physostigmine given after soman does not protect AChE from irreversible inhibition by the OP and that the observed therapeutic effect of physostigmine in nerve agent poisoning in vivo is probably due to other factors.

  10. Grape (Vitis vinifera) extracts protect against radiation-induced oxidative stress in human erythrocyte (red blood cell)

    Singha, Indrani; Das, Subir Kumar; Gautam, S.

    2016-01-01

    Ionizing radiation (IR) causes oxidative stress through the overwhelming generation of reactive oxygen species (ROS) in the living cells leading further to the oxidative damage to biomolecules. Grapes (Vitis vinifera) contain several bioactive phytochemicals and are the richest source of antioxidant. In this study, we investigated and compared in vitro antioxidant activity and DNA damage protective property of the grape extracts of four different cultivars, including the Thompson seedless, Flame seedless, Kishmish chorni and Red globe. The activities of ascorbic acid oxidase and catalase significantly (p<0.01) differed among extracts within the same cultivar, while that of peroxidase and polyphenol oxidase did not differ significantly among extracts of any cultivar. In vitro antioxidant activities were assessed by ferric-reducing antioxidant power (FRAP) assay and ABTS. The superoxide radical-scavenging activity was higher in the seed as compared to the skin or pulp of the same cultivar. Pretreatment with grape extracts attenuates oxidative stress induced by 4 Gy γ-radiation in human erythrocytes in vitro. These results suggest that grape extract serve as a potential source of natural antioxidants against the IR-induced oxidative stress and also inhibit apoptosis. Furthermore, the protective action of grape depends on the source of extract (seed, skin or pulp) and type of the cultivars. (author)

  11. Local anesthetics: interaction with human erythrocyte membranes as studied by 1H and 31P nuclear magnetic resonance

    Fraceto, Leonardo Fernandes; Paula, Eneida de

    2004-01-01

    The literature carries many theories about the mechanism of action of local anesthetics (LA). We can highlight those focusing the direct effect of LA on the sodium channel protein and the ones that consider the interaction of anesthetic molecules with the lipid membrane phase. The interaction between local anesthetics and human erythrocyte membranes has been studied by 1 H and 31 P nuclear magnetic resonance spectroscopy. It was found that lidocaine (LDC) and benzocaine (BZC) bind to the membranes, increase the mobility of the protons of the phospholipids acyl chains, and decrease the mobility and/or change the structure of the polar head groups. The results indicate that lidocaine molecules are inserted across the polar and liquid interface of the membrane, establishing both electrostatic (charged form) and hydrophobic (neutral form) interactions. Benzocaine locates itself a little deeper in the bilayer, between the interfacial glycerol region and the hydrophobic core. These changes in mobility or conformation of membrane lipids could affect the Na + -channel protein insertion in the bilayer, stabilizing it in the inactivated state, thus causing anesthesia. (author)

  12. Lysis of fresh human solid tumors by autologous lymphocytes activated in vitro with lectins

    Mazumder, A.; Grimm, E.A.; Zhang, H.Z.; Rosenberg, S.A.

    1982-01-01

    Human peripheral blood lymphocytes (PBL), obtained from patients with a variety of cancers, were incubated in vitro with phytohemagglutinin, concanavalin A, and crude or lectin-free T-cell growth factors. The lectin-activated PBL of nine patients were capable of lysing fresh autologous tumor during a 4-hr 51Cr release assay. Multiple metastases from the same patient were equivalently lysed by these activated autologous PBL. No lysis of fresh PBL or lectin-induced lymphoblast cell targets was seen, although tumor, PBL, and lymphoblast cells were shown to be equally lysable using allosensitized cells. The activated cells could be expanded without loss of cytotoxicity in crude or lectin-free T-cell growth factors. The generation of cells lytic to fresh autologous tumor was dependent on the presence of adherent cells, although the lytic cell itself was not adherent. Proliferation was not involved in the induction of lytic cells since equal lysis was induced in irradiated and nonirradiated lymphocytes. Lectin was not required in the lytic assay, and the addition of alpha-methyl-D-mannoside to concanavalin A-activated lymphoid cells did not increase the lysis of fresh tumor cells. Activation by lectin for 3 days appears to be an efficient and convenient method for generating human cells lytic to fresh autologous tumor. These lytic cells may be of value for studies of the cell-mediated lysis of human tumor and possibly for tumor immunotherapy as well

  13. Effects of tartrazine on proliferation and genetic damage in human lymphocytes.

    Atlı Şekeroğlu, Zülal; Güneş, Büşra; Kontaş Yedier, Seval; Şekeroğlu, Vedat; Aydın, Birsen

    2017-06-01

    The color additive, tartrazine (TRZ), is widely used in food products, drugs and cosmetics. Genotoxicity of TRZ and its metabolites has not been investigated in detail in the presence and absence of a metabolic activator (S9 mix) in human. Therefore, the aim of this study is to investigate the cytotoxic and genotoxic effects of TRZ and its metabolites on cultured human lymphocytes by using chromosome aberration (CA) and micronucleus (MN) tests. Cultures were treated with 625, 1250 and 2500 μg/ml of TRZ in the presence and absence of S9 mix. TRZ showed cytotoxic activity at the highest concentration due to significant decrease in mitotic index (MI) in the absence of S9 mix when compared with solvent control. TRZ and metabolites significantly increased the CAs and aberrant cells in the presence and absence of S9 mix at the higher concentrations. Increased MN values in cultures with and without S9 mix were found to significantly at the highest concentration when tested. Our results indicated that while both TRZ and its metabolites have genotoxic potential on human lymphocyte cultures with and without S9 mix, TRZ can induce cytotoxicity at the highest concentration in culture without S9 mix under the experimental conditions.

  14. Large-scale in vitro expansion of polyclonal human switched-memory B lymphocytes.

    Sonia Néron

    Full Text Available Polyclonal preparations of therapeutic immunoglobulins, namely intravenous immunoglobulins (IVIg, are essential in the treatment of immunodeficiency and are increasingly used for the treatment of autoimmune and inflammatory diseases. Currently, patients' accessibility to IVIg depends exclusively upon volunteer blood donations followed by the fractionation of pooled human plasma obtained from thousands of individuals. Presently, there are no in vitro cell culture procedures allowing the preparation of polyclonal human antibodies. All in vitro human therapeutic antibodies that are currently generated are based on monoclonal antibodies, which are mostly issued from genetic engineering or single cell antibody technologies. Here, we describe an in vitro cell culture system, using CD40-CD154 interactions, that leads to a 1×10(6-fold expansion of switched memory B lymphocytes in approximately 50 days. These expanded cells secrete polyclonal IgG, which distribution into IgG(1, IgG(2, IgG(3 and IgG(4 is similar to that of normal human serum. Such in vitro generated IgG showed relatively low self-reactivity since they interacted moderately with only 24 human antigens among a total of 9484 targets. Furthermore, up to one liter of IgG secreting cells can be produced in about 40 days. This experimental model, providing large-scale expansion of human B lymphocytes, represents a critical step toward the in vitro production of polyclonal human IgG and a new method for the ex vivo expansion of B cells for therapeutic purposes.

  15. Dietary indicaxanthin from cactus pear (Opuntia ficus-indica L. Mill) fruit prevents eryptosis induced by oxysterols in a hypercholesterolaemia-relevant proportion and adhesion of human erythrocytes to endothelial cell layers.

    Tesoriere, Luisa; Attanzio, Alessandro; Allegra, Mario; Livrea, Maria A

    2015-08-14

    Toxic oxysterols in a hypercholesterolaemia-relevant proportion cause suicidal death of human erythrocytes or eryptosis. This process proceeds through early production of reactive oxygen species (ROS), release of prostaglandin (PGE2) and opening of PGE2-dependent Ca channels, membrane phosphatidylserine (PS) externalisation, and cell shrinkage. The present study was the first to reveal that a bioavailable phytochemical, indicaxanthin (Ind) from cactus pear fruit, in a concentration range (1.0-5.0 μM) consistent with its plasma level after a fruit meal, prevents PS externalisation and cell shrinkage in a dose-dependent manner when incubated with isolated healthy human erythrocytes exposed to an oxysterol mixture for 48 h. Dietary Ind inhibited ROS production, glutathione (GSH) depletion, PGE2 release and Ca2+ entry. Ind alone did not modify the erythrocyte redox environment or affect other parameters. Ex vivo spiking of normal human blood with the oxysterol mixture for 48 h induced eryptosis, resulting in the production of ROS and decreased levels of GSH, which was prevented by concurrent exposure to 5 μm-Ind. The adherence of eryptotic erythrocytes to the endothelium causes vascular tissue injury. Erythrocytes isolated from blood incubated with the oxysterol mixture plus 5 μm-Ind did not adhere to endothelial cell monolayers. Eryptotic erythrocytes may contribute to thrombotic complications in hypercholesterolaemia. Our findings suggest the positive effects of diets containing Ind on erythrocytes in hypercholesterolaemic subjects.

  16. Interaction of Epstein-Barr virus (EBV) with human B-lymphocytes

    Klein, George; Klein, Eva; Kashuba, Elena

    2010-01-01

    Epstein-Barr virus, EBV, and humans have a common history that reaches back to our primate ancestors. The virus co-evolved with man and has established a largely harmless and highly complex co-existence. It is carried as silent infection by almost all human adults. A serendipitous discovery established that it is the causative agent of infectious mononucleosis. Still, EBV became known first in 1964, in a rare, geographically prevalent malignant lymphoma of B-cell origin, Burkitt lymphoma BL. Its association with a malignancy prompted intensive studies and its capacity to immortalize B-lymphocytes in vitro was soon demonstrated. Consequently EBV was classified therefore as a potentially tumorigenic virus. Despite of this property however, the virus carrier state itself does not lead to malignancies because the transformed cells are recognized by the immune response. Consequently the EBV induced proliferation of EBV carrying B-lymphocytes is manifested only under immunosuppressive conditions. The expression of EBV encoded genes is regulated by the cell phenotype. The virus genome can be found in malignancies originating from cell types other than the B-lymphocyte. Even in the EBV infected B-cell, the direct transforming capacity is restricted to a defined window of differentiation. A complex interaction between virally encoded proteins and B-cell specific cellular proteins constitute the proliferation inducing program. In this short review we touch upon aspects which are the subject of our present work. We describe the mechanisms of some of the functional interactions between EBV encoded and cellular proteins that determine the phenotype of latently infected B-cells. The growth promoting EBV encoded genes are not expressed in the virus carrying BL cells. Still, EBV seems to contribute to the etiology of this tumor by modifying events that influence cell survival and proliferation. We describe a possible growth promoting mechanism in the genesis of Burkitt lymphoma

  17. Interaction of Epstein-Barr virus (EBV) with human B-lymphocytes

    Klein, George, E-mail: Georg.Klein@ki.se [Karolinska Institutet, Department of Microbiology, Tumor and Cell Biology (MTC), Box 280, S171 77 Stockholm (Sweden); Klein, Eva; Kashuba, Elena [Karolinska Institutet, Department of Microbiology, Tumor and Cell Biology (MTC), Box 280, S171 77 Stockholm (Sweden)

    2010-05-21

    Epstein-Barr virus, EBV, and humans have a common history that reaches back to our primate ancestors. The virus co-evolved with man and has established a largely harmless and highly complex co-existence. It is carried as silent infection by almost all human adults. A serendipitous discovery established that it is the causative agent of infectious mononucleosis. Still, EBV became known first in 1964, in a rare, geographically prevalent malignant lymphoma of B-cell origin, Burkitt lymphoma BL. Its association with a malignancy prompted intensive studies and its capacity to immortalize B-lymphocytes in vitro was soon demonstrated. Consequently EBV was classified therefore as a potentially tumorigenic virus. Despite of this property however, the virus carrier state itself does not lead to malignancies because the transformed cells are recognized by the immune response. Consequently the EBV induced proliferation of EBV carrying B-lymphocytes is manifested only under immunosuppressive conditions. The expression of EBV encoded genes is regulated by the cell phenotype. The virus genome can be found in malignancies originating from cell types other than the B-lymphocyte. Even in the EBV infected B-cell, the direct transforming capacity is restricted to a defined window of differentiation. A complex interaction between virally encoded proteins and B-cell specific cellular proteins constitute the proliferation inducing program. In this short review we touch upon aspects which are the subject of our present work. We describe the mechanisms of some of the functional interactions between EBV encoded and cellular proteins that determine the phenotype of latently infected B-cells. The growth promoting EBV encoded genes are not expressed in the virus carrying BL cells. Still, EBV seems to contribute to the etiology of this tumor by modifying events that influence cell survival and proliferation. We describe a possible growth promoting mechanism in the genesis of Burkitt lymphoma

  18. Necroptosis takes place in human immunodeficiency virus type-1 (HIV-1-infected CD4+ T lymphocytes.

    Ting Pan

    Full Text Available Human immunodeficiency virus type 1 (HIV-1 infection is characterized by progressive depletion of CD4+ T lymphocytes and dysfunction of the immune system. The numbers of CD4+ T lymphocytes in the human body are maintained constantly by homeostatic mechanisms that failed during HIV-1 infection, resulting in progressive loss of CD4+ T cells mainly via apoptosis. Recently, a non-apoptotic form of necrotic programmed cell death, named necroptosis, has been investigated in many biological and pathological processes. We then determine whether HIV-1-infected cells also undergo necroptosis. In this report, we demonstrate that HIV-1 not only induces apoptosis, but also mediates necroptosis in the infected primary CD4+ T lymphocytes and CD4+ T-cell lines. Necroptosis-dependent cytopathic effects are significantly increased in HIV-1-infected Jurkat cells that is lack of Fas-associated protein-containing death domain (FADD, indicating that necroptosis occurs as an alternative cell death mechanism in the absence of apoptosis. Unlike apoptosis, necroptosis mainly occurs in HIV-infected cells and spares bystander damage. Treatment with necrostatin-1(Nec-1, a RIP1 inhibitor that specifically blocks the necroptosis pathway, potently restrains HIV-1-induced cytopathic effect and interestingly, inhibits the formation of HIV-induced syncytia in CD4+ T-cell lines. This suggests that syncytia formation is mediated, at least partially, by necroptosis-related processes. Furthermore, we also found that the HIV-1 infection-augmented tumor necrosis factor-alpha (TNF-α plays a key role in inducing necroptosis and HIV-1 Envelope and Tat proteins function as its co-factors. Taken together,necroptosis can function as an alternative cell death pathway in lieu of apoptosis during HIV-1 infection, thereby also contributing to HIV-1-induced cytopathic effects. Our results reveal that in addition to apoptosis, necroptosis also plays an important role in HIV-1-induced pathogenesis.

  19. Effect of in vitro x-irradiation on human peripheral blood T and B lymphocytes

    Prusek, W.; Astaldi, G.

    1979-01-01

    The effect of in vitro irradiation with increasing in logarythmic progress X-ray doses on lymphocyte viability and on T and B lymphocyte populations was studied in normal adults, patients with myasthenia gravis and in patients undergoing long-term steroid therapy. Decrease in numbers of lymphocytes carrying T or B lymphocyte surface markers was higher than the viable cell loss. The decrease showed no linear correlation with X-ray doses applied, which might reflect the existence of radioresistant T and B lymphocytes. A higher so-called early radiosensitivity of B lymphocytes was demonstrated. In patients with myasthenia gravis early radioresistance of T lymphocytes was detected. In patients undergoing long-term steroid therapy, an increase in numbers of cells lacking markers of any of lymphocyte populations was found in parallel with a decrease in T lymphocyte number which, in these patients, showed a higher radiosensitivity. (author)

  20. Effect of in vitro x-irradiation on human peripheral blood T and B lymphocytes

    Prusek, W. (Szpital Wojewodzki, Wroclaw (Poland)); Astaldi, G. (The Blood Research Foundation Centre, Tortona (Italy))

    1979-01-01

    The effect of in vitro irradiation with increasing in logarythmic progress X-ray doses on lymphocyte viability and on T and B lymphocyte populations was studied in normal adults, patients with myasthenia gravis and in patients undergoing long-term steroid therapy. Decrease in numbers of lymphocytes carrying T or B lymphocyte surface markers was higher than the viable cell loss. The decrease showed no linear correlation with X-ray doses applied, which might reflect the existence of radioresistant T and B lymphocytes. A higher so-called early radiosensitivity of B lymphocytes was demonstrated. In patients with myasthenia gravis early radioresistance of T lymphocytes was detected. In patients undergoing long-term steroid therapy, an increase in numbers of cells lacking markers of any of lymphocyte populations was found in parallel with a decrease in T lymphocyte number which, in these patients, showed a higher radiosensitivity.

  1. Immunoglobulin production in human mixed lymphocyte cultures: implications for co-cultures of cells from patients and healthy donors

    Ruemke, H.C.; Terpstra, F.G.; Huis, B.; Out, T.A.; Zeijlemaker, W.P.

    1982-01-01

    When human peripheral blood lymphocytes (PBL) are cultured in the presence of irradiated allogeneic lymphocytes, the resulting mixed lymphocyte reaction (MLR) leads to the secretion into the supernatant of substantial amounts of IgM and IgG, derived from nonirradiated responder B lymphocytes. Our data indicate that stimulation to Ig production by responder B cells may result from different types of of interactions. First, B cells and monocytes among the irradiated stimulator cells activate T responder B cells to produce Ig; second, ''responder'' B cells activate irradiated ''stimulator'' T cells, leading to a ''helper'' signal, back to the responder B cells and leading to Ig production. The latter system is radiosensitive, because allogeneic T cells, irradiated at a dose of 4000 rad or more, failed to induce Ig production by responder B cells. In some combinations of human allogeneic lymphocytes, the co-culture of the cells leads to inhibition of Ig production, both in the presence and in the absence of PWM. Thus, co-culture of allogeneic cells may cause ''positive'' as well as ''negative'' allogeneic effects. The implications of these findings for the interpretation of co-cultures that are aimed at establishing defects in lymphocytes from patients with, for example, immunodeficiencies, who fail to produce Ig in the presence of PWM are discussed

  2. Plant polyphenols mobilize nuclear copper in human peripheral lymphocytes leading to oxidatively generated DNA breakage: implications for an anticancer mechanism.

    Shamim, Uzma; Hanif, Sarmad; Ullah, M F; Azmi, Asfar S; Bhat, Showket H; Hadi, S M

    2008-08-01

    It was earlier proposed that an important anti-cancer mechanism of plant polyphenols may involve mobilization of endogenous copper ions, possibly chromatin-bound copper and the consequent pro-oxidant action. This paper shows that plant polyphenols are able to mobilize nuclear copper in human lymphocytes, leading to degradation of cellular DNA. A cellular system of lymphocytes isolated from human peripheral blood and comet assay was used for this purpose. Incubation of lymphocytes with neocuproine (a cell membrane permeable copper chelator) inhibited DNA degradation in intact lymphocytes. Bathocuproine, which is unable to permeate through the cell membrane, did not cause such inhibition. This study has further shown that polyphenols are able to degrade DNA in cell nuclei and that such DNA degradation is inhibited by neocuproine as well as bathocuproine (both of which are able to permeate the nuclear pore complex), suggesting that nuclear copper is mobilized in this reaction. Pre-incubation of lymphocyte nuclei with polyphenols indicates that it is capable of traversing the nuclear membrane. This study has also shown that polyphenols generate oxidative stress in lymphocyte nuclei which is inhibited by scavengers of reactive oxygen species (ROS) and neocuproine. These results indicate that the generation of ROS occurs through mobilization of nuclear copper resulting in oxidatively generated DNA breakage.

  3. Unexpected role of the L-domain of calpastatin during the autoproteolytic activation of human erythrocyte calpain.

    De Tullio, Roberta; Franchi, Alice; Martines, Antonino; Averna, Monica; Pedrazzi, Marco; Melloni, Edon; Sparatore, Bianca

    2018-04-26

    Autoproteolysis of human erythrocyte calpain-1 proceeds in vitro at high [Ca 2+ ], through the conversion of the 80-kDa catalytic subunit into a 75-kDa activated enzyme that requires lower [Ca 2+ ] for catalysis. Importantly, here we detect a similar 75 kDa calpain-1 form also in vivo , in human meningiomas. Although calpastatin is so far considered the specific inhibitor of calpains, we have previously identified in rat brain a calpastatin transcript truncated at the end of the L-domain (cast110, L-DOM), coding for a protein lacking the inhibitory units. Aim of the present study was to characterize the possible biochemical role of the L-DOM during calpain-1 autoproteolysis in vitro , at high (100 µM) and low (5 µM) [Ca 2+ ]. Here we demonstrate that the L-DOM binds the 80 kDa proenzyme in the absence of Ca 2+ Consequently, we have explored the ability of the 75 kDa activated protease to catalyze at 5 µM Ca 2+ the intermolecular activation of native calpain-1 associated with the L-DOM. Notably, this [Ca 2+ ] is too low to promote the autoproteolytic activation of calpain-1 but enough to support the catalysis of the 75 kDa calpain. We show for the first time that the L-DOM preserves native calpain-1 from the degradation mediated by the 75 kDa form. Taken together, our data suggest that the free L-domain of calpastatin is a novel member of the calpain/calpastatin system endowed with a function alternative to calpain inhibition. For this reason, it will be crucial to define the intracellular relevance of the L-domain in controlling calpain activation/activity in physiopathological conditions having altered Ca 2+ homeostasis. © 2018 The Author(s).

  4. Modeling hysteresis observed in the human erythrocyte voltage-dependent cation channel

    Flyvbjerg, Henrik; Gudowska-Nowak, Ewa; Christophersen, Palle

    2012-01-01

    The non-selective voltage-activated cation channel from human red cells, which is activated at depolarizing potentials, has been shown to exhibit counter-clockwise gating hysteresis. Here, we analyze this phenomenon with the simplest possible phenomenological models. Specifically, the hysteresis ...

  5. Synergistic effect of DHT and IGF-1 hyperstimulation in human peripheral blood lymphocytes.

    Imperlini, Esther; Spaziani, Sara; Mancini, Annamaria; Caterino, Marianna; Buono, Pasqualina; Orrù, Stefania

    2015-06-01

    The abuse of mixed or combined performance-enhancing drugs is widespread among athletes and amateurs, adults and adolescents. Clinical studies demonstrated that misuse of these doping agents is associated with serious adverse effects to many organs in human. Previously, we demonstrated in human peripheral blood lymphocytes that high doses of anabolic androgenic steroids, such as dihydrotestosterone (DHT) and growth factors, such as insulin-like growth factor-1 (IGF-1), have effects at gene and protein levels. Supraphysiological treatments of DHT and IGF-1 affected the expression of genes involved in skeletal muscle disorders as well as in cell-mediated immunological response. At protein level, DHT hyperdosage affects cell motility and apoptosis; IGF-1 hyperstimulation triggers an active cytoskeletal reorganization and an overproduction of immune response- and inflammation-related cytokines. In this study, we investigate the combined effects of DHT and IGF-1 hyperdosage in peripheral blood lymphocytes using a differential proteomic approach. DHT and IGF-1 combined treatment affects cell adhesion, migration, and survival through modulation of expression levels of cytokines and paxillin-signaling-related proteins, and activation of several pathways downstream focal adhesion kinase. Our results indicate a synergistic effect of DHT and IGF-1 which has potential implications for health risk factors. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Mobile phone radiofrequency exposure has no effect on DNA double strand breaks (DSB) in human lymphocytes.

    Danese, Elisa; Lippi, Giuseppe; Buonocore, Ruggero; Benati, Marco; Bovo, Chiara; Bonaguri, Chiara; Salvagno, Gian Luca; Brocco, Giorgio; Roggenbuck, Dirk; Montagnana, Martina

    2017-07-01

    The use of mobile phones has been associated with an increased risk of developing certain type of cancer, especially in long term users. Therefore, this study was aimed to investigate the potential genotoxic effect of mobile phone radiofrequency exposure on human peripheral blood mononuclear cells in vitro. The study population consisted in 14 healthy volunteers. After collection of two whole blood samples, the former was placed in a plastic rack, 1 cm from the chassis of a commercial mobile phone (900 MHz carrier frequency), which was activated by a 30-min call. The second blood sample was instead maintained far from mobile phones or other RF sources. The influence of mobile phone RF on DNA integrity was assessed by analyzing γ-H2AX foci in lymphocytes using immunofluorescence staining kit on AKLIDES. No measure of γ-H2AX foci was significantly influenced by mobile phone RF exposure, nor mobile phone exposure was associated with significant risk of genetic damages in vitro (odds ratio comprised between 0.27 and 1.00). The results of this experimental study demonstrate that exposure of human lymphocytes to a conventional 900 MHz RF emitted by a commercial mobile phone for 30 min does not significantly impact DNA integrity.

  7. Effect of estradiol on radiation-induced chromosome aberrations in human lymphocytes

    Kanda, Reiko; Hayata, Isamu

    1999-01-01

    As a part of studies on physiological factors that affect radiosensitivity, we examined the in vitro effect of estradiol (E2) on the yield of radiation-induced chromosome aberrations in human peripheral lymphocytes. Lymphocytes were cultured for 3 days in the medium containing E2 at 0-100000 ng/ml. On the second day, they were irradiated by X-rays at 3 Gy, and then 2% phytohemagglutinin and 0.05 μg/ml colcemid were added to the medium. After further 48 h, mitotic indices and the yields of chromosome aberrations were examined at various E2 concentrations. E2 treatment at concentrations above 1000 ng/ml resulted in dose-related inhibition of mitosis. Repeated experiments showed that the yield of dicentrics plus centric rings in the culture containing E2 at 100 ng/ml was significantly higher than the yields at 0 ng/ml. Similarly, the yield of total chromosome breaks in the culture containing E2 at 100 ng/ml was significantly higher than that at 1 ng/ml. This study provides the direct evidence in human that radiosensitivity may vary in relation to hormonal conditions. (author)

  8. Protective effect of grape seed extracts on human lymphocytes: a preliminary study.

    Szeto, Yim Tong; Lee, Kit Yee; Kalle, Wouter; Pak, Sok Cheon

    2013-03-01

    Grape seed extracts (GSEs) possess a broad spectrum of antioxidative properties that protects various cells from free radicals and oxidative stress. In this study, the genoprotective effect of GSE on human lymphocytic DNA was studied using standard and lysed cell comet assays. Lymphocytes from 5 healthy subjects were pretreated with GSE in different concentrations. The standard and lysed cell comet assays were performed on treated, untreated, challenged, and unchallenged cells in parallel. Cells were then subjected to an oxidant challenge induced with 5-min exposures to hydrogen peroxide. In the standard comet assay, GSE significantly diminished hydrogen-peroxide-induced DNA damage in a dose-dependent manner. In the lysed cell assay, however, the antioxidant effect was diminished at a higher GSE concentration. Data indicate that the cell membrane might play a role in limiting cellular access to antioxidants, which directly affects the genoprotective or potential pro-oxidant effect of antioxidants on human DNA. Using both standard and lysed cell comet assays in parallel could be a useful way to elucidate the mechanism of protection or damage by antioxidants.

  9. Grapevine fruit extract protects against radiation-induced oxidative stress and apoptosis in human lymphocyte

    Singha, Indrani; Das, Subir Kumar

    2015-01-01

    Ionizing radiation (IR) causes oxidative stress through overwhelming generation of reactive oxygen species (ROS) in the living cells leading the oxidative damage further to biomolecules. Grapevine (Vitis vinifera L.) posses several bioactive phytochemicals and is the richest source of antioxidants. In this study, we investigated V. vinifera for its phytochemical content, enzymes profile and, ROS-and oxidant-scavenging activities. We have also studied the fruit extract of four different grapevine viz., Thompson seedless, Flame seedless, Kishmish chorni and Red globe for their radioprotective actions in human lymphocytes. The activities of ascorbic acid oxidase and catalase significantly (P < 0.01) differed among extracts within the same cultivar, while that of peroxidase and polyphenol oxidase did not differ significantly. The superoxide radical-scavenging activity was higher in the seed as compared to the skin or pulp of the same cultivar. Pretreatment with grape extracts attenuated the oxidative stress induced by 4 Gy γ-radiation in human lymphocytes in vitro. Further, γ-radiation-induced increase in caspase 3/7 activity was significantly attenuated by grape extracts. These results suggest that grape extract serve as a potential source of natural antioxidants against the IR-induced oxidative stress and also inhibit apoptosis. Furthermore, the protective action of grape depends on the source of extract (seed, skin or pulp) and type of the cultivars. (author)

  10. DNA damage in human lymphocytes exposed to four food additives in vitro.

    Yilmaz, Serkan; Unal, Fatma; Yüzbaşıoğlu, Deniz; Celik, Mustafa

    2014-11-01

    In vitro genotoxic effects of antioxidant additives, such as citric acid (CA) and phosphoric acid (PA) and their combination, as well as antimicrobial additives, such as benzoic acid (BA) and calcium propionate (CP), on human lymphocytes were determined using alkaline single-cell gel electrophoresis. There was a significant increase in the DNA damage in human lymphocytes after 1 h of in vitro exposure to CA, PA, BA and CP (200, 25-200, 50-500, 50-1000 μg/mL, respectively). The combination of CA and PA significantly increased the mean tail intensity at all the concentrations used (25-200 μg/mL) and significantly increased the mean tail length mainly after higher concentrations (100 and 200 μg/mL). Data in this study showed that the concentrations of food additives used induce DNA damage and PA was the most genotoxic and CA was less genotoxic additives among them. © The Author(s) 2012.

  11. Effect of drinking water disinfection by-products in human peripheral blood lymphocytes and sperm.

    Ali, Aftab; Kurzawa-Zegota, Malgorzata; Najafzadeh, Mojgan; Gopalan, Rajendran C; Plewa, Michael J; Anderson, Diana

    2014-12-01

    Drinking water disinfection by-products (DBPs) are generated by the chemical disinfection of water and may pose hazards to public health. Two major classes of DBPs are found in finished drinking water: haloacetic acids (HAAs) and trihalomethanes (THMs). HAAs are formed following disinfection with chlorine, which reacts with iodide and bromide in the water. Previously the HAAs were shown to be cytotoxic, genotoxic, mutagenic, teratogenic and carcinogenic. To determine the effect of HAAs in human somatic and germ cells and whether oxidative stress is involved in genotoxic action. In the present study both somatic and germ cells have been examined as peripheral blood lymphocytes and sperm. The effects of three HAA compounds: iodoacetic acid (IAA), bromoacetic acid (BAA) and chloroacetic acid (CAA) were investigated. After determining appropriate concentration responses, oxygen radical involvement with the antioxidants, butylated hydroxanisole (BHA) and the enzyme catalase, were investigated in the single cell gel electrophoresis (Comet) assay under alkaline conditions, >pH 13 and the micronucleus assay. In the Comet assay, BHA and catalase were able to reduce DNA damage in each cell type compared to HAA alone. In the micronucleus assay, micronuclei (MNi) were found in peripheral lymphocytes exposed to all three HAAs and catalase and BHA were in general, able to reduce MNi induction, suggesting oxygen radicals play a role in both assays. These observations are of concern to public health since both human somatic and germ cells show similar genotoxic responses. Copyright © 2014. Published by Elsevier B.V.

  12. In vivo induction of apoptosis in human lymphocytes by therapeutic fractionated total body irradiation

    Delic, J.; Magdelenat, H.; Barbaroux, C.; Chaillet, M.-P.; Dubray, B.; Fourquet, A.; Cosset, J.-M.; Gluckman, E.; Girinsky, T.

    1995-01-01

    Ionizing radiations have been reported as an in vitro apoptosis initiating stimulus in human lymphocytes. As the cytotoxicity of ionizing radiations and chemotherapeutic agents appears to be dependent on the efficacy of cell death induction, the manipulation of apoptosis initiation might be used as a means to suppress some pathological process. In the present study the in vivo induction of γ-ray mediated programmed cell death in humans is reported. The in vivo induction of apoptosis in peripheral blood lymphocytes (PBL) by ionizing radiations was investigated in 33 patients after each of two sessions (2 Gy and 4 Gy) of fractionated total body irradiation (FTBI) as part of their conditioning regimen before bone marrow transplantation. PBL committed to apoptosis were scored before irradiation (S1), 4 h (S2) and 24 h after 2 Gy (S3, 14-17 h after the second 2 Gy fraction). Nuclear morphology and chromatin-DNA were analysed by fluorescence microscopy immediately after blood sample withdrawal (I) and after 24 h in cell culture medium (II). (author)

  13. The effect of stem cell from human exfoliated deciduous teeth on T lymphocyte proliferation.

    Alipour, Razieh; Adib, Minoo; Hashemi-Beni, Batool; Sadeghi, Farzaneh

    2014-01-01

    Mesenchymal stem cells (MSC), a specific type of adult tissue stem cell; have the immunosuppressive effects that make them valuable targets for regenerative medicine and treatment of many human illnesses. Hence, MSC have been the subject of numerous studies. The classical source of MSC is adult bone marrow (BM). Due to many shortcomings of harvesting MSC from BM, finding the alternative sources for MSC is an urgent. Stem cells from human exfoliated deciduous teeth (SHED) are relative new MSC populations that fulfill these criteria but their potential immunosuppressive effect has not been studied enough yet. Thus, in this work the effect of SHED on the proliferation of in vitro activated T lymphocytes were explored. In this study, both mitogen and alloantigen activated T cells were cultured in the presence of different numbers of SHED. In some co-cultures, activated T cells were in direct contact to MSCs and in other co-cultures; they were separated from SHED by a permeable membrane. In all co-cultures, the proliferation of T cells was measured by ELISA Bromodeoxyuridine proliferation assay. In general, our results showed that SHED significantly suppress the proliferation of activated T cells in a dose-dependent manner. Moreover, the suppression was slightly stronger when MSCs were in physical contact to activated T cells. This study showed that SHED likewise other MSC populations can suppress the activation of T lymphocytes, which can be used instead of BM derived MSCs in many investigational and clinical applications.

  14. Fungal beta glucan protects radiation induced DNA damage in human lymphocytes.

    Pillai, Thulasi G; Maurya, Dharmendra K; Salvi, Veena P; Janardhanan, Krishnankutty K; Nair, Cherupally K K

    2014-02-01

    Ganoderma lucidum (Ling Zhi), a basidiomycete white rot macrofungus has been used extensively for therapeutic use in China, Japan, Korea and other Asian countries for 2,000 years. The present study is an attempt to investigate its DNA protecting property in human lymphocytes. Beta glucan (BG) was isolated by standard procedure and the structure and composition were studied by infrared radiation (IR) and nuclear magnetic resonance (NMR) spectroscopy, gel filtration chromatography and paper chromatography. The radioprotective properties of BG isolated from the macro fungi Ganoderma lucidum was assessed by single cell gel electrophoresis (comet assay). Human lymphocytes were exposed to 0, 1, 2 and 4 Gy gamma radiation in the presence and absence of BG. The comet parameters were reduced by BG. The results indicate that the BG of G. lucidum possessed significant radioprotective activity with DNA repairing ability and antioxidant activity as the suggestive mechanism. The findings suggest the potential use of this mushroom for the prevention of radiation induced cellular damages.

  15. Studies on chromosome aberrations induced in human lymphocytes by very low-dose exposure to tritium

    Hori, T.; Moriya, Junko; Nakai, Sayaka

    1978-01-01

    Assessment of potential hazard from environmental tritium to man becomes very important with increasing the development of nuclear-power industry. However, little data are available as to the determination on the genetic effect of tritium especially at the low levels. The object of the present study is to obtain quantitative data for chromosome aberrations in human lymphocytes, as an indicator for genetic risk estimation, induced by tritium at very low dose levels. Leukocyte cultures of human peripheral blood were chronically exposed for 48h to tritiated water and 3 H-thymidine using a wide range of tritium doses, and aberrations in lymphocyte chromosomes at the first metaphases were examined. In the experimental conditions, the types of aberrations induced by radiation emitted from both tritiated water and 3 H-thymidine were mostly chromatid types, such as chromatid gaps and deletions. The dose-response relations for chromatid breaks per cell exhibited unusual dose-dependency in both cases. It was demonstrated that at higher dose range the yields of chromatid breaks increased linearly with dose, while those at lower dose range were significantly higher than would be expected by a downward extraporation from the linear relation. Partial-hit or partial-target kinetics events appeared at very low dose exposure. (author)

  16. The distribution of chromosome aberrations among chromosomes of karyotype in exposed human lymphocyte

    Que Tran; Tien Hoang Hung

    1997-01-01

    Induced chromosome aberrations (ch. ab.) in exposed Human peripheral blood lymphocyte have been used to assay radio.bio.doses, because of their characters such as: the maintaining Go phase in cell cycle in body, the distribution of cell in blood system and the distribution of ch. ab. in exposed cells of body and among chromosomes of karyotype. The frequency of ch. ab. reflected the quantity of radiation dose, dose rate and radiation energy. The dependence between radiation dose and frequency of ch. ab. was illustrated by the mathematic equations. The distribution of induced ch. ab. among the cells exposed to uniform radiation fields was Poisson's, but the distribution of ch. ab. among chromosomes in karyotype depended on radiation field and mononucleotid sequence of DNA molecular of each chromosome. The minimum influence of mononucleotid sequence of DNA molecular in inform ch. ab. will be advantageous state for dose-assessments. The location of induced ch. ab. in exposed Human lymphocyte had been determined by karyotype analyses. The data of statistic analyse had improved that the number of ch. ab. depended on the size of chromosomes in karyotype. The equal distribution of ch. ab.among chromosomes in karyotype provided the objectiveness and the accuracy of using the chromosomal aberrant analysis technique on bio-dosimetry. (author)

  17. Behavior of exposed human lymphocytes to a neutron beam of the Reactor TRIGA Mark III

    Carbajal R, M. I.; Arceo M, C.; Aguilar H, F.; Guerrero C, C.

    2012-10-01

    The living beings are permanently exposed to radiations of natural origin: cosmic and geologic, as well as the artificial radiations that come from sources elaborated by the man. The artificial sources have an important use in the medical area. Particularly has been increased the neutrons use due to the effectiveness that they have to damage the cells with regard to other radiation types. The biological indicator of exposition to ionizing radiation more reliable is the chromosomal aberrations study, specifically the dicentrics in human lymphocytes. This test allows, establishing the exposition dose in function of the damage quantity. The dicentrics have a behavior in function of the dose. The calibration curve that describes this behavior is specific for each type of ionizing radiation. In the year 2006 beginning was given to the expositions of human lymphocytes to a neutron beam generated in the reactor TRIGA Mark III of the Instituto Nacional de Investigaciones Nucleares (ININ) in Mexico. Up to 2008 the response dose curve comprised an interval of exposition time of up to 30 minutes. Moreover, the interval between 10 an 20 minutes is included, since was observed that this last is indispensable for the adjustment waited in a lineal model. (Author)

  18. Evaluation of cytogenetic and DNA damage in human lymphocytes treated with adrenaline in vitro.

    Djelić, Ninoslav; Radaković, Milena; Spremo-Potparević, Biljana; Zivković, Lada; Bajić, Vladan; Stevanović, Jevrosima; Stanimirović, Zoran

    2015-02-01

    Catechol groups can be involved in redox cycling accompanied by generation of reactive oxygen species (ROS) which may lead to oxidative damage of cellular macromolecules including DNA. The objective of this investigation was to evaluate possible genotoxic effects of a natural catecholamine adrenaline in cultured human lymphocytes using cytogenetic (sister chromatid exchange and micronuclei) and the single cell gel electrophoresis (Comet) assay. In cytogenetic tests, six experimental concentrations of adrenaline were used in a range from 0.01-500 μM. There were no indications of genotoxic effects of adrenaline in sister chromatid exchange and micronucleus tests. However, at four highest concentrations of adrenaline (5 μM, 50 μM, 150 μM and 300 μM) we observed a decreased mitotic index and cell-cycle delay. In addition, in the Comet assay we used adrenaline in a range from 0.0005-500 μM, at two treatment times: 15 min or 60 min. In contrast to cytogenetic analysis, there was a dose-dependent increase of DNA damage detected in the Comet assay. These effects were significantly reduced by concomitant treatment with quercetin or catalase. Therefore, the obtained results indicate that adrenaline may exhibit genotoxic effects in cultured human lymphocytes, most likely due to production of reactive oxygen species. Copyright © 2014 Elsevier Ltd. All rights reserved.

  19. The role of electrostatic interactions in the Streptococcus thermophilus adhesion on human erythrocytes in media with different 1:1 electrolyte concentration

    О. І. Гордієнко

    2015-10-01

    Full Text Available The process of bacterial adhesion is usually discussed in terms of the two-stage sorption model. According to the model, at the first stage the bacteria fastly attaches to the surface by weak physical interactions, while at the second stage irreversible molecular and cellular adhesion process takes place. An important factor, influencing the adhesion processes, is physical-chemical characteristics of the medium, in particular, the presence of monovalent cations therein. The aim of this work is to assess the role of electrostatic component of the intercellular interactions at the first reversible stage of adhesion. Comparison of experimental data of adhesion of lactobacilli S. thermophilus on human erythrocytes and theoretical definition of the Debye radius and the erythrocytes surface potential in the experimental solutions showed that with decreasing ionic strength of the solution the change in the adhesion index in our experiments is fully in line with the theory DLVO predictions.

  20. Effects of lithium on the functions of human neutrophils and lymphocytes in vitro and in vivo

    Anderson, R.; Walters, L.; Grabow, G.; Van der Merwe, M.; Van Rensburg, C.E. (Pretoria Univ. (South Africa))

    1982-10-02

    The effects of lithium sulphate (LiSO/sub 4/) at concentrations ranging from 10/sup -7/M to 10/sup -2/M on human polymorphonuclear leucocyte (PMNL) and lymphocyte functions in vitro were investigated. The leucocyte functions assessed were PMNL motility, post-phagocytic hexose-monophosphate shunt activity, myeloperoxidase-mediated iodination of Candida albicans and lymphocyte transformation to mitogens. These same functions as well the results of serological studies were assessed in normal volunteers prior to ingestion of lithium carbonate (LiCO/sub 3/), 2 hours and 24 hours after the ingestion of a single oral dose of 480 mg LiCO/sub 3/ and on the 4th day of ingestion of 2x480 mg LiCO/sub 3/ tablets daily. Incubation of PMNL with LiSO/sub 4/ at concentrations up to 10/sup -3/M had no detectable effects on motility or post-phagocytic metabolic activity. Higher concentrations (10/sup -3/M) inhibited these functions. Likewise, at concentrations up to 1x10/sup -4/M LiSO/sub 4/ had no effects on mitogen-induced transformation of lymphocytes, although higher concentrations did inhibit this activity. These same leucocyte functions were unaffected by ingestion of LiCO/sub 3/. Levels of serum immunoglobulins and complement components, total haemolytic complement activity and salivary lgA values also remained unaltered. In vitro investigations showed that at a concentration of 10/sup -3/M LiSO/sub 4/ had no inhibitory effects on the stimulation of PMNL motility mediated by ascorbate, levamisole and thiamine.

  1. Regulation of interferon receptor expression in human blood lymphocytes in vitro and during interferon therapy

    Lau, A.S.; Hannigan, G.E.; Freedman, M.H.; Williams, B.R.

    1986-01-01

    Interferons (IFN) elicit antiviral and antineoplastic activities by binding to specific receptors on the cell surface. The binding characteristics of IFN to human lymphocytes were studied using IFN alpha 2 labeled with 125 I to high specific activity. The specific binding curves generated were analyzed by the LIGAND program of Munson and Rodbard to determine receptor numbers. The number of receptors in peripheral blood lymphocytes (PBL) and tonsillar B-lymphocytes (TBL) from normal individuals were 505 +/- 293 (n = 10) and 393 +/- 147 (n = 3) respectively. When these cells were preincubated in vitro with unlabeled IFN alpha 2, the receptor number decreased to 82 +/- 45 and 61 +/- 16 respectively. Receptor binding activities recovered gradually over a period of 72 h when the cells were incubated in IFN-free medium. This recovery of receptors could be blocked by the addition of actinomycin D to the incubation medium. A similar decrease in receptor expression was observed in vivo in PBL from patients being treated daily with 5 X 10(6) units/m2 per d of IFN alpha 2 by subcutaneous injection, for acute lymphoblastic leukemia or papilloma virus infections. Receptor numbers in PBL in vivo were further reduced concurrent with the progression of IFN therapy. Thus, the reduction in IFN receptor expression observed in vitro can be demonstrated in vivo. These studies indicate that monitoring IFN receptor expression in vivo can provide information regarding the availability of IFN receptors at the cell surface for the mediation of IFN actions during the course of IFN therapy

  2. Prediction for the occurrence of clonal chromosome aberrations in human blood lymphocytes

    Nakano, M.; Kadama, Y.; Ohtaki, K.; Itoh, M.; Awa, A.; Cologne, J.; Nakamura, N.

    2003-01-01

    Full text: Identical chromosome aberrations among multiple blood lymphocytes in a blood sample (clonal aberrations) are encountered occasionally during cytogenetic examination of radiation-exposed people. Clonal aberrations are found primarily among high-dose exposed people but no systematic surveys were ever conducted. Therefore, the underlying mechanism is unknown. Here we conducted a large-scale screening for detecting clonal aberrations using FISH followed by Q-banding. Examinations of 500 cells from each of 513 A-bomb survivors led us to detect 96 clones. The clonal cell fraction (Cf) varied from 0.6% to 20% among the 500 cells. As the number of clonal event was inversely proportional to Cf, we hypothesized that the progenitor cells vary extensively in the number of offspring that they can produce and relative number of progenitor cells decreases as the increase of treatment, while other genes such as DNA repair proteinsnumber of progenitor cells capable to form clones (Cf >=0.6%) to be 2 (1 to 3) in non-exposed individuals. The number increased to up to 7 among the high-dose exposed survivors. Further, our preliminary results for the origins of 10 clones indicated that both hematopoietic stem cells (HSCs) and mature T cells contributed to the clone formation roughly equally. Thus, the estimated number of 2 in non-exposed individuals is shared as one HSC and one mature T cells. The model could neatly explain the frequency of clones in two reports. Our model predicts that clonal aberrations are rarely found but clonal expansion of T lymphocytes occurs commonly. In fact, clonal expansions of non-aberrant cells are reported using TCR gene rearrangement patterns as a marker. We now understand the rough structure of lymphocyte pool in humans and can predict the probability of detecting a clone if the individual frequency of non-clonal translocations and the number of cells scored are given

  3. Induction of adaptive response in human blood lymphocytes exposed to radiofrequency radiation.

    Sannino, Anna; Sarti, Maurizio; Reddy, Siddharth B; Prihoda, Thomas J; Vijayalaxmi; Scarfì, Maria Rosaria

    2009-06-01

    The incidence of micronuclei was evaluated to assess the induction of an adaptive response to non-ionizing radiofrequency (RF) radiation in peripheral blood lymphocytes collected from five different human volunteers. After stimulation with phytohemagglutinin for 24 h, the cells were exposed to an adaptive dose of 900 MHz RF radiation used for mobile communications (at a peak specific absorption rate of 10 W/kg) for 20 h and then challenged with a single genotoxic dose of mitomycin C (100 ng/ml) at 48 h. Lymphocytes were collected at 72 h to examine the frequency of micronuclei in cytokinesis-blocked binucleated cells. Cells collected from four donors exhibited the induction of adaptive response (i.e., responders). Lymphocytes that were pre-exposed to 900 MHz RF radiation had a significantly decreased incidence of micronuclei induced by the challenge dose of mitomycin C compared to those that were not pre-exposed to 900 MHz RF radiation. These preliminary results suggested that the adaptive response can be induced in cells exposed to non-ionizing radiation. A similar phenomenon has been reported in cells as well as in animals exposed to ionizing radiation in several earlier studies. However, induction of adaptive response was not observed in the remaining donor (i.e., non-responder). The incidence of micronuclei induced by the challenge dose of mitomycin C was not significantly different between the cells that were pre-exposed and unexposed to 900 MHz RF radiation. Thus the overall data indicated the existence of heterogeneity in the induction of an adaptive response between individuals exposed to RF radiation and showed that the less time-consuming micronucleus assay can be used to determine whether an individual is a responder or non-responder.

  4. Evaluation of toxicity of essential oils palmarosa, citronella, lemongrass and vetiver in human lymphocytes.

    Sinha, Sonali; Jothiramajayam, Manivannan; Ghosh, Manosij; Mukherjee, Anita

    2014-06-01

    The present investigation was undertaken to study the cytotoxic and genotoxic potential of the essential oils (palmarosa, citronella, lemongrass and vetiver) and monoterpenoids (citral and geraniol) in human lymphocytes. Trypan blue dye exclusion and MTT test was used to evaluate cytotoxicity. The genotoxicity studies were carried out by comet and DNA diffusion assays. Apoptosis was confirmed by Annexin/PI double staining. In addition, generation of reactive oxygen species was evaluated by DCFH-DA staining using flow cytometry. The results demonstrated that the four essential oils and citral induced cytotoxicity and genotoxicity at higher concentrations. The essential oils were found to induce oxidative stress evidenced by the generation of reactive oxygen species. With the exception of geraniol, induction of apoptosis was confirmed at higher concentrations of the test substances. Based on the results, the four essential oils are considered safe for human consumption at low concentrations. Copyright © 2014 Elsevier Ltd. All rights reserved.

  5. Rapid alterations of cell cycle control proteins in human T lymphocytes in microgravity

    Thiel Cora S

    2012-01-01

    Full Text Available Abstract In our study we aimed to identify rapidly reacting gravity-responsive mechanisms in mammalian cells in order to understand if and how altered gravity is translated into a cellular response. In a combination of experiments using "functional weightlessness" provided by 2D-clinostats and real microgravity provided by several parabolic flight campaigns and compared to in-flight-1g-controls, we identified rapid gravity-responsive reactions inside the cell cycle regulatory machinery of human T lymphocytes. In response to 2D clinorotation, we detected an enhanced expression of p21 Waf1/Cip1 protein within minutes, less cdc25C protein expression and enhanced Ser147-phosphorylation of cyclinB1 after CD3/CD28 stimulation. Additionally, during 2D clinorotation, Tyr-15-phosphorylation occurred later and was shorter than in the 1 g controls. In CD3/CD28-stimulated primary human T cells, mRNA expression of the cell cycle arrest protein p21 increased 4.1-fold after 20s real microgravity in primary CD4+ T cells and 2.9-fold in Jurkat T cells, compared to 1 g in-flight controls after CD3/CD28 stimulation. The histone acetyltransferase (HAT inhibitor curcumin was able to abrogate microgravity-induced p21 mRNA expression, whereas expression was enhanced by a histone deacetylase (HDAC inhibitor. Therefore, we suppose that cell cycle progression in human T lymphocytes requires Earth gravity and that the disturbed expression of cell cycle regulatory proteins could contribute to the breakdown of the human immune system in space.

  6. Radiation damage to human erythrocytes. Relative contribution of hydroxyl and chloride radicals in N2O-saturated buffers

    Krokosz, Anita; Komorowska, Magdalena A.; Szweda-Lewandowska, Zofia

    2008-01-01

    The erythrocyte suspensions in Na-phosphate buffered isotonic NaCl solution (PBS) or Na-phosphate isotonic buffer (PB) (hematocrit 1%) were irradiated with the dose of 400 Gy under N 2 O. Erythrocytes were incubated in the medium in which the cells were irradiated or in fresh PBS. The level of damage to cells was estimated on the basis of the course of post-radiation hemolysis and hemoglobin (Hb) oxidation. The medium in which the cells were irradiated and incubated influenced the course of the post-radiation hemolysis and Hb oxidation as well as some other parameters. We discussed the contribution of hydroxyl and chloride radicals in the initiation of erythrocyte damage and oxygen modification of these processes

  7. Computed aided system for separation and classification of the abnormal erythrocytes in human blood

    Wąsowicz, Michał; Grochowski, Michał; Kulka, Marek; Mikołajczyk, Agnieszka; Ficek, Mateusz; Karpieńko, Katarzyna; Cićkiewicz, Maciej

    2017-12-01

    The human peripheral blood consists of cells (red cells, white cells, and platelets) suspended in plasma. In the following research the team assessed an influence of nanodiamond particles on blood elements over various periods of time. The material used in the study consisted of samples taken from ten healthy humans of various age, different blood types and both sexes. The markings were leaded by adding to the blood unmodified diamonds and oxidation modified. The blood was put under an impact of two diamond concentrations: 20μl and 100μl. The amount of abnormal cells increased with time. The percentage of echinocytes as a result of interaction with nanodiamonds in various time intervals for individual specimens was scarce. The impact of the two diamond types had no clinical importance on red blood cells. It is supposed that as a result of longlasting exposure a dehydratation of red cells takes place, because of the function of the cells. The analysis of an influence of nanodiamond particles on blood elements was supported by computer system designed for automatic counting and classification of the Red Blood Cells (RBC). The system utilizes advanced image processing methods for RBCs separation and counting and Eigenfaces method coupled with the neural networks for RBCs classification into normal and abnormal cells purposes.

  8. Apolipoprotein J/Clusterin is a novel structural component of human erythrocytes and a biomarker of cellular stress and senescence.

    Marianna H Antonelou

    Full Text Available BACKGROUND: Secretory Apolipoprotein J/Clusterin (sCLU is a ubiquitously expressed chaperone that has been functionally implicated in several pathological conditions of increased oxidative injury, including aging. Nevertheless, the biological role of sCLU in red blood cells (RBCs remained largely unknown. In the current study we identified sCLU as a component of human RBCs and we undertook a detailed analysis of its cellular topology. Moreover, we studied the erythrocytic membrane sCLU content during organismal aging, in conditions of increased organismal stress and accelerated RBCs senescence, as well as during physiological in vivo cellular senescence. METHODOLOGY/PRINCIPAL FINDINGS: By using a combination of molecular, biochemical and high resolution microscopical methods we found that sCLU is a novel structural component of RBCs extra- and intracellular plasma membrane and cytosol. We observed that the RBCs membrane-associated sCLU decreases during organismal aging or exposure to acute stress (e.g. smoking, in patients with congenital hemolytic anemia, as well as during RBCs in vivo senescence. In all cases, sCLU reduction paralleled the expression of typical cellular senescence, redox imbalance and erythrophagocytosis markers which are also indicative of the senescence- and oxidative stress-mediated RBCs membrane vesiculation. CONCLUSIONS/SIGNIFICANCE: We propose that sCLU at the mature RBCs is not a silent remnant of the erythroid precursors, but an active component being functionally implicated in the signalling mechanisms of cellular senescence and oxidative stress-responses in both healthy and diseased organism. The reduced sCLU protein levels in the RBCs membrane following cell exposure to various endogenous or exogenous stressors closely correlates to the levels of cellular senescence and redox imbalance markers, suggesting the usefulness of sCLU as a sensitive biomarker of senescence and cellular stress.

  9. Contribution of ankyrin-band 3 complexes to the organization and mechanical properties of the membrane skeleton of human erythrocyte

    Shen, B.W. [Argonne National Lab., IL (United States). Biological and Medical Research Div.

    1995-02-01

    To understand the role of ankyrin-band 3 complexes in the organization of the spectrin-based membrane skeleton and its contribution to the mechanical properties of human erythrocytes, intact skeletons and single-layered skeleton leaflets were prepared from intact and physically sheared membrane ghosts, expanded in low salt buffer, and examined by transmission electron microscopy. While the structures of intact skeletons and single-layered skeleton leaflets shared many common features, including rigid junctional complexes of spectrin, actin, and band 4.1; short stretches ({approximately}50 {angstrom}) of flexible spectrin filaments; and globular masses of ankyrin-band 3 complexes situated close to the middle of the spectrin filaments, the definition of structural units in the intact skeleton is obscured by the superposition of the two layers. However, the spatial disposition of structural elements can be clearly defined in the images of the single-layered skeleton leaflets. Partially expanded skeletal leaflets contain conglomerates of ankyrin-band 3 complexes arranged in a circular or clove-leaf configuration that straddles multiple strands of thick spectrin cables, presumably reflecting the association of ankyrin-band 3 complexes on neighboring spectrin tetramers as well as the lateral association of the spectrin filaments. Hyperexpansion of the skeleton leaflets led to dissociation of the conglomerates of ankyrin-band 3 complexes, full-extension of the spectrin tetramers, and separation of the individual strands of spectrin tetramers. Clearly defined stands of spectrin tetramers in the hyperexpanded single-layered skeletal leaflets often contained two sets of globular protein masses that divided the spectrin tetramers into three segments of approximately equal length.

  10. Rapid degradation of D- and L-succinimide-containing peptides by a post-proline endopeptidase from human erythrocytes

    Momand, J.; Clarke, S.

    1987-12-01

    The authors have been interested in the metabolic fate of proteins containing aspartyl succinimide (Asu) residues. These residues can be derived from the spontaneous rearrangement of Asp and Asn residues and from the spontaneous demethylation of enzymatically methylated L-isoAsp and D-Asp residues. Incubation of the synthetic hexapeptide N-Ac-Val-Tyr-Pro-Asu-Gly-Ala with the cytosolic fraction of human erythrocytes resulted in rapid cleavage of the prolyl-aspartyl succinimide bond producing the tripeptide N-Ac-Val-Try-Pro. The rate of this reaction is equal for both L- and D-Asu-containing peptides and is 10-fold greater that the rate of cleavage of a corresponding peptide containing a normal Pro-Asp linkage. When the aspartyl succinimide ring was replaced with an isoaspartyl residue, the cleavage rate was about 5 times that of the normal Pro-Asp peptide. The tripeptide-producing activity copurified on DEAE-cellulose chromatography with an activity that cleaves N-carbobenzoxy-Gly-Pro-4-methylcoumarin-7-amide, a post-proline endopeptidase substrate. These two activities were both inhibited by an antiserum to rat brain post-proline endopeptidase, and it appears that they are catalyzed by the same enzyme. This enzyme has a molecular weight of approximately 80,000 and is covalently labeled and inhibited by (/sup 3/H) diisopropyl fluorophosphate. The facile cleavage of the succinimide- and isoaspartyl-containing peptides by this post-proline endopeptidase suggests that it may play a role in the metabolism of peptides containing altered aspartyl residues.

  11. Ebselen exhibits glycation-inhibiting properties and protects against osmotic fragility of human erythrocytes in vitro.

    Soares, Julio C M; Folmer, Vanderlei; Da Rocha, João B T; Nogueira, Cristina W

    2014-05-01

    Diabetic status is associated with an increase on oxidative stress markers in humans and animal models. We have investigated the in vitro effects of high concentrations of glucose on the profile of oxidative stress and osmotic fragility of blood from control and diabetic patients; we considered whether its antioxidant properties could afford some protection against glucose-induced osmotic fragility, and whether ebselen could act as an inhibitor of hemoglobin glycation. Raising blood glucose to 5-100 mmol/L resulted in a concentration-dependent increase of glycated hemoglobin (HbA1c; P Ebselen significantly reduced the glucose-induced increase in osmotic fragility and inhibited HbA1c formation (P < 0.0001). These results indicate that blood from patients with uncontrolled diabetes are more sensitive to osmotic shock than from patients with controlled diabetes and control subjects in relation to increased production of free radicals in vivo. © 2014 International Federation for Cell Biology.

  12. Radioprotective effect of sesamol on γ-radiation induced DNA damage, lipid peroxidation and antioxidants levels in cultured human lymphocytes

    Prasad, N. Rajendra; Menon, Venugopal P.; Vasudev, V.; Pugalendi, K.V.

    2005-01-01

    Sesamol pretreated (1, 5 and 10 μg/ml) lymphocytes were exposed to different doses of γ-radiation, i.e., 1, 2 and 4 Gray (Gy) and the cellular changes were estimated by using cytokinesis blocked micronucleus assay (MN), dicentric aberration (DC), thiobarbituric acid reactive substances (TBARS), reduced glutathione (GSH) and the activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx). Radiation significantly increased MN, DC frequencies, TBARS levels and decreased GSH and antioxidant enzyme levels in a dose dependent manner. The highest damage to lymphocytes was observed at 4 Gy irradiation. On the other hand, sesamol pretreatment significantly decreased MN, DC frequencies, TBARS levels and increased GSH levels and SOD, CAT and GPx activities in a concentration dependent manner. At 1 Gy irradiation all concentrations of sesamol (1, 5 and 10 μg/ml) significantly protects the lymphocytes from radiation damage. At 2 Gy irradiation 5 and 10 μg/ml of sesamol shows significant radioprotection. Since the highest damage was observed at 4 Gy irradiation both 1 and 5 μg/ml of sesamol pretreatment were not sufficient to protect the lymphocytes from radiation damage but 10 μg/ml of sesamol significantly (p < 0.05) protects the lymphocytes from radiation effect. Thus, sesamol pretreatment gives significant protection to cultured human lymphocytes against γ-radiation induced cellular damage. The possible mechanism involved in the radioprotective influence of sesamol is discussed

  13. Genotoxic and cytotoxic effects of different types of dental cement on normal cultured human lymphocytes.

    Bakopoulou, A; Mourelatos, D; Tsiftsoglou, A S; Giassin, N P; Mioglou, E; Garefis, P

    2009-01-31

    In this study we have investigated the genotoxic and cytotoxic effects of eluates derived from different types of commercially available dental cements, including glass ionomer cements (GICs) (Ketac Cem/3M ESPE and GC Fuji I/GC Corp), resin-modified glass ionomer cements (RM-GICs) (RelyX Luting/3M ESPE and Vitrebond/3M ESPE) and dual-cure resin cements (RCs) (Variolink II/ Ivoclar-Vivadent and Panavia F 2.0/Kuraray) on normal cultured human lymphocytes. Lymphocyte primary cultures obtained from blood samples of three healthy donors were exposed to serial dilutions of eluates derived from specimens of each material tested. Metaphases were induced with phytohaemagglutinin, collected after 72h treatment by use of colchicine and stained according to the fluorescence plus giemsa (FPG) procedure. Preparations were scored for sister chromatid exchange (SCE) and chromosomal aberrations (CAs), while the proliferation rate index (PRI) was also calculated. Our results show that eluates derived from the RM-GICs and RCs caused severe genotoxic effects by significantly increasing the frequencies of SCEs and CAs in cultures of peripheral blood lymphocytes and by decreasing the relevant PRI values in a dose-dependent manner, whereas the two GICs caused only minor cytogenetic effects. Eluates of the two RM-GICs (Vitrebond and RelyX) were also very cytotoxic, as the first serial dilutions of both materials caused a complete mitotic arrest in lymphocyte cultures. Overall, the degree of genotoxicity and cytotoxicity caused by dental cements decreased as follows: Viterbond>Rely X>Panavia F 2.0>Variolink II>Ketac Cem=GC Fuji I. These results indicate that different types of dental cement differ extensively in their genotoxic and cytotoxic potential and their ability to affect chromosomal integrity, cell-cycle progression, DNA replication and repair. Although these results cannot be directly extrapolated to the clinical situation, the potential occurrence of adverse effects caused by the

  14. Gentiana asclepiadea and Armoracia rusticana can modulate the adaptive response induced by zeocin in human lymphocytes.

    Hudecova, A; Hasplova, K; Kellovska, L; Ikreniova, M; Miadokova, E; Galova, E; Horvathova, E; Vaculcikova, D; Gregan, F; Dusinska, M

    2012-01-01

    Zeocin is a member of bleomycin/phleomycin family of antibiotics isolated from Streptomyces verticullus. This unique radiomimetic antibiotic is known to bind to DNA and induce oxidative stress in different organisms producing predominantly single- and double- strand breaks, as well as a DNA base loss resulting in apurinic/apyrimidinic (AP) sites. The aim of this study was to induce an adaptive response (AR) by zeocin in freshly isolated human lymphocytes from blood and to observe whether plant extracts could modulate this response. The AR was evaluated by the comet assay. The optimal conditions for the AR induction and modulation were determined as: 2 h-intertreatment time (in PBS, at 4°C) given after a priming dose (50 µg/ml) of zeocin treatment. Genotoxic impact of zeocin to lymphocytes was modulated by plant extracts isolated from Gentiana asclepiadea (methanolic and aqueous haulm extracts, 0.25 mg/ml) and Armoracia rusticana (methanolic root extract, 0.025 mg/ml). These extracts enhanced the AR and also decreased DNA damage caused by zeocin (after 0, 1 and 4 h-recovery time after the test dose of zeocin application) to more than 50%. These results support important position of plants containing many biologically active compounds in the field of pharmacology and medicine.

  15. Biological dosimetry: the potential use of radiation-induced apoptosis in human T-lymphocytes

    Menz, R.; Andres, R.; Larsson, B.; Ozsahin, M.; Crompton, N.E.A.; Trott, K.

    1997-01-01

    An assay for biological dosimetry based on the induction of apoptosis in human T-lymphocytes is described. Radiation-induced apoptosis was assessed by flow cytometric identification of cells displaying apoptosis-associated DNA condensation. CD4 and CD8 T-lymphocytes were analysed. They were recognized on the basis of their cell-surface antigens. Four parameters were measured for both cell types: cell size, granularity, antigen immunofluorescence and DNA content. Apoptosis was quantified as the fraction of CD4-, or CD8-positive cells with a characteristic reduction of cell size and DNA content. At doses below 1 Gy, levels of radiation-induced apoptosis increased for up to 5 days after irradiation. Optimal dose discrimination was observed 4 days after irradiation, at which time the dose-response curves were linear, with a slope of 8% ± 0.5% per 0.1 Gy. In controlled, dose-response experiments the lowest dose level at which the radiation-induced apoptosis frequency was still significantly above control was 0.05 Gy. After 5 days post-irradiation incubation, intra- and interdonor variations were measured and found to be similar; thus, apoptotic levels depend more on the dose than on the donor. The results demonstrate the potential of this assay as a biological dosimeter. (orig.)

  16. Chromosome aberrations in human lymphocytes exposed to tritiated water in vitro

    Bocian, E.; Ziemba-zak, B.; Rosiek, O.; Sablinski, J.

    1978-01-01

    The induction of chromosome aberrations in human peripheral blood lymphocytes by tritiated water or 180 kV X-rays in vitro was studied. Lymphocytes were exposed to various concentrations of HTO for 2 h or for 53 h. Chromosome and chromatid type aberrations were scored during the first mitotic division after stimulation with phytohaemagglutinin. For the analysis of the dose-response relationship the data were fitted by the method of least-squares to different models. After acute exposure to tritium β-rays and X-rays, the dicentrics + centric rings and terminal + interstitial deletions gave the best fit to the linear-quadratic function. However, data for these types of aberrations after 53 h exposure to HTO gave equally good fit to the linear and linear-quadratic functions. The best description of the dose-response relationship for chromatid aberrations is given by the linear model. In the system studied the RBE of tritium β-rays as compared to 180 KV X-rays was 1.17+-0.02. (Auth.)

  17. Chromosome aberration yields in human lymphocytes induced by fractionated doses of x-radiation

    Purrott, R.J.; Reeder, E.

    1976-01-01

    Unstimulated (G 0 ) human peripheral blood lymphocytes were exposed at 37degC to doses of 200 or 500 rad of X-rays delivered in two equal fractions. The dose fractions were separated by intervals of up to 7 h in the 200 rad study and up to 48 h for 500 rad. In both studies the mean levels of dicentrics and total unstable aberrations began to decline when fractions were delivered with intervals of greater than 2 h. With 200 rad the yield had decreased to an additive baseline (i.e. equal to only twice the yield of a single 100-rad fraction) by an interval of 4 h. Following 500 rad the yield declined until 8 h and then remained 20% above the expected additive baseline even when 48 h separated the fractions. Possible explanations for this discrepancy are discussed. In a second experiment PHA stimulated lymphocyte cultures were exposed to 2 doses of 125 rad of X-rays up to 7 h apart in an attempt to demonstrate the late peak in aberration yield originally reported by Lane. Control cultures received unsplit doses of 250 rad at the time of the corresponding second 125-rad fraction. No evidence of a late peak in dicentric yield was observed. The yield remained approximately the same irrespective of the time interval between fractions but these split dose yields were significantly different from the accompanying unsplit controls

  18. Differential Micronuclei Induction in Human Lymphocyte Cultures by Imidacloprid in the Presence of Potassium Nitrate

    Polychronis Stivaktakis

    2010-01-01

    Full Text Available Humans are exposed to pesticides as a consequence of their application in farming or their persistence in a variety of media, including food, water, air, soil, plants, animals, and smoke. The interaction of pesticides with environmental factors may result in the alteration of their physicochemical properties. Square wave cathodic stripping voltammetry (SW-CSV, a technique that simulates electrodynamically the cellular membrane, is used to investigate whether the presence of potassium nitrate (KNO3 in the culture medium interferes with the genotoxic behavior of imidacloprid. The cytokinesis block micronuclei (CBMN method is used to evaluate imidacloprid's genotoxicity in the absence or presence of KNO3 in the culture medium and, as a consequence, its adsorption by lymphocytes. Comparing micronuclei (MN frequencies in control and imidacloprid-treated blood cell cultures, statistically significant differences were not detected. KNO3 did not induce MN frequencies compared to control. Statistically significant differences in MN frequencies were observed when blood cell cultures were treated with imidacloprid in the presence of increasing concentrations of KNO3. SW-CSV revealed that by increasing KNO3 molarity, imidacloprid's concentration in the culture medium decreased in parallel. This finding indicates that imidacloprid is adsorbed by cellular membranes. The present study suggests a novel role of a harmless environmental factor, such as KNO3, on the genotoxic behavior of a pesticide, such as imidacloprid. KNO3 rendered imidacloprid permeable to lymphocytes, resulting in elevated MN frequencies.

  19. Effect of propolis on mitotic and cellular proliferation indices in human blood lymphocytes

    Montoro, A.; Almonacid, M.; Villaescusa, J. [Valencia Hospital Univ. la Fe, Servicio de Proteccion Radiologica (Spain); Barquinero, J. [Barcelona Univ. Autonom, Servicio de Dosimetria Biologica, Unidad de Antropologia, Dept. de Biologia Animal, Vegetal y Ecologia, barcelona (Spain); Barrios, L. [Barcelona Univ. Autonoma, Dept. de Biologia Celular y Fisiologia. Unidad de Biologia Celular (Spain); Verdu, G. [Valencia Univ. Politecnica, Dept. de Ingenieria Quimica y Nuclear (Spain); Perez, J. [Hospital la Fe, Seccion de Radiofisica, Servicio de Radioterapia, valencia (Spain)

    2006-07-01

    The study of the frequency of chromosomal aberrations per cell is the tool used in Biological dosimetry studies. Using dose-effect calibration curve obtained in our laboratory, we can evaluate the radioprotector effect of the EEP (ethanolic extract of propolis) in cultures in vitro. Propolis is the generic name for resinous substance collected by honeybees. The results showed a reduction in chromosomal aberrations's frequency of up to 50 %. The following study consisted of analyzing human peripheral blood lymphocytes exposed to 2 Gy {gamma} rays, in presence and absence of EEP, the change in the frequency of chromosome aberrations was analysed with biological dosimetry. The protection against the formation of dicentric and ring was dose-dependent, but there seemed to be a maximum protection, i.e. a further increase in the concentration of EEP does not show additional protection. This work studies the effect of the EEP of the cellular cycle using the mitotic and cellular proliferation index, as an alternative for the screening cytostatic activity. The results indicate that the lymphocytes which were cultures in presence of EEP exhibited a significant and dependent-concentration decrease in mitotic index and proliferation kinetics. The possible mechanisms involved in the radioprotective influence of EEP are discussed. (authors)

  20. Evaluation of an Immunomodulator Drug as a Radioprotectant on Human Peripheral Blood Lymphocytes In Vitro

    Zahra Sattarpour

    2018-01-01

    Full Text Available Background: IMOD™, a selenium enriched extract of the plants Tanacetum vulgare, Urtica dioica, and Rosa canina, has an excellent effect on oxidative stress. In this study, we investigated the radioprotective effects of this immunomodulatory drug on human peripheral blood lymphocytes. Methods: Peripheral blood samples obtained from venipuncture of the brachial vein were treated with IMOD™ (5, 10, 15, 20 μl for 30 min and Cobalt 60 γ-rays (0.25, 0.5, 1, 2 Gy as the test groups and cultured with the control. We used the micronuclei assay, cell death detection, and cell toxicity assay to analyze the treatment effects. Results: The frequency of micronuclei were 1.66 (0 Gy, 5.33 (0.25 Gy, 9.67 (0.5 Gy, 17.67 (1 Gy, and 23.67 (2 Gy in the irradiated lymphocytes (P<0.001. The percentage of micronuclei frequency reduced to 20%, 26.83%, 37.68%, 16%, and 20.47% with IMOD™. Apoptosis and necrosis decreased significantly in the IMOD™ treated groups (P<0.05. Conclusion: IMOD™ may protect these cells against ionizing radiation.

  1. Scoring of radiation-induced micronuclei in cytokinesis-blocked human lymphocytes by automated image analysis

    Verhaegen, F.; Seuntjens, J.; Thierens, H.

    1994-01-01

    The micronucleus assay in human lymphocytes is, at present, frequently used to assess chromosomal damage caused by ionizing radiation or mutagens. Manual scoring of micronuclei (MN) by trained personnel is very time-consuming, tiring work, and the results depend on subjective interpretation of scoring criteria. More objective scoring can be accomplished only if the test can be automated. Furthermore, an automated system allows scoring of large numbers of cells, thereby increasing the statistical significance of the results. This is of special importance for screening programs for low doses of chromosome-damaging agents. In this paper, the first results of our effort to automate the micronucleus assay with an image-analysis system are represented. The method we used is described in detail, and the results are compared to those of other groups. Our system is able to detect 88% of the binucleated lymphocytes on the slides. The procedure consists of a fully automated localization of binucleated cells and counting of the MN within these cells, followed by a simple and fast manual operation in which the false positives are removed. Preliminary measurements for blood samples irradiated with a dose of 1 Gy X-rays indicate that the automated system can find 89% ± 12% of the micronuclei within the binucleated cells compared to a manual screening. 18 refs., 8 figs., 1 tab

  2. Effect of propolis on mitotic and cellular proliferation indices in human blood lymphocytes

    Montoro, A.; Almonacid, M.; Villaescusa, J.; Barquinero, J.; Barrios, L.; Verdu, G.; Perez, J.

    2006-01-01

    The study of the frequency of chromosomal aberrations per cell is the tool used in Biological dosimetry studies. Using dose-effect calibration curve obtained in our laboratory, we can evaluate the radioprotector effect of the EEP (ethanolic extract of propolis) in cultures in vitro. Propolis is the generic name for resinous substance collected by honeybees. The results showed a reduction in chromosomal aberrations's frequency of up to 50 %. The following study consisted of analyzing human peripheral blood lymphocytes exposed to 2 Gy γ rays, in presence and absence of EEP, the change in the frequency of chromosome aberrations was analysed with biological dosimetry. The protection against the formation of dicentric and ring was dose-dependent, but there seemed to be a maximum protection, i.e. a further increase in the concentration of EEP does not show additional protection. This work studies the effect of the EEP of the cellular cycle using the mitotic and cellular proliferation index, as an alternative for the screening cytostatic activity. The results indicate that the lymphocytes which were cultures in presence of EEP exhibited a significant and dependent-concentration decrease in mitotic index and proliferation kinetics. The possible mechanisms involved in the radioprotective influence of EEP are discussed. (authors)

  3. Biodosimetry of ionizing radiation by selective painting of prematurely condensed chromosomes in human lymphocytes

    Durante, M.; George, K.; Yang, T. C.

    1997-01-01

    Painting of interphase chromosomes can be useful for biodosimetric purposes in particular cases such as radiation therapy, accidental exposure to very high radiation doses and exposure to densely ionizing radiation, for example during space missions. Biodosimetry of charged-particle radiation is analyzed in the present paper. Target cells were human peripheral blood lymphocytes irradiated in vitro with gamma rays, protons and iron ions. After exposure, lymphocytes were incubated for different times to allow repair of radiation-induced damage and then fused to mitotic hamster cells to promote premature condensation in the interphase chromosomes. Chromosome spreads were then hybridized with whole-chromosome DNA probes labeled with fluorescent stains. Dose-response curves for the induction of chromatin fragments shortly after exposure, as well as the kinetics of rejoining and misrejoining, were not markedly dependent on linear energy transfer. However, after exposure to heavy ions, more aberrations were scored in the interphase cells after incubation for repair than in metaphase samples harvested at the first postirradiation mitosis. On the other hand, no significant differences were observed in the two samples after exposure to sparsely ionizing radiation. These results suggest that interphase chromosome painting can be a useful tool for biodosimetry of particle radiation.

  4. Protective Effects of Ferulic Acid on High Glucose-Induced Protein Glycation, Lipid Peroxidation, and Membrane Ion Pump Activity in Human Erythrocytes.

    Weerachat Sompong

    Full Text Available Ferulic acid (FA is the ubiquitous phytochemical phenolic derivative of cinnamic acid. Experimental studies in diabetic models demonstrate that FA possesses multiple mechanisms of action associated with anti-hyperglycemic activity. The mechanism by which FA prevents diabetes-associated vascular damages remains unknown. The aim of study was to investigate the protective effects of FA on protein glycation, lipid peroxidation, membrane ion pump activity, and phosphatidylserine exposure in high glucose-exposed human erythrocytes. Our results demonstrated that FA (10-100 μM significantly reduced the levels of glycated hemoglobin (HbA1c whereas 0.1-100 μM concentrations inhibited lipid peroxidation in erythrocytes exposed to 45 mM glucose. This was associated with increased glucose consumption. High glucose treatment also caused a significant reduction in Na+/K+-ATPase activity in the erythrocyte plasma membrane which could be reversed by FA. Furthermore, we found that FA (0.1-100 μM prevented high glucose-induced phosphatidylserine exposure. These findings provide insights into a novel mechanism of FA for the prevention of vascular dysfunction associated with diabetes.

  5. Origin of nuclear buds and micronuclei in normal and folate-deprived human lymphocytes

    Lindberg, Hanna K.; Wang Xu; Jaerventaus, Hilkka; Falck, Ghita C.-M.; Norppa, Hannu; Fenech, Michael

    2007-01-01

    Micronuclei are formed from chromosomes and chromosomal fragments that lag behind in anaphase and are left outside daughter nuclei in telophase. They may also be derived from broken anaphase bridges. Nuclear buds, micronucleus-like bodies attached to the nucleus by a thin nucleoplasmic connection, have been proposed to be generated similarly to micronuclei during nuclear division or in S-phase as a stage in the extrusion of extra DNA, possibly giving rise to micronuclei. To better understand these phenomena, we have characterized the contents of 894 nuclear buds and 1392 micronuclei in normal and folate-deprived 9-day cultures of human lymphocytes using fluorescence in situ hybridization with pancentromeric and pantelomeric DNA probes. Such information has not earlier been available for human primary cells. Surprisingly, there appears to be no previous data on the occurrence of telomeres in micronuclei (or buds) of normal human cells in general. Our results suggest that nuclear buds and micronuclei have partly different mechanistic origin. Interstitial DNA without centromere or telomere label was clearly more prevalent in nuclear buds (43%) than in micronuclei (13%). DNA with only telomere label or with both centromere and telomere label was more frequent in micronuclei (62% and 22%, respectively) than in nuclear buds (44% and 10%, respectively). Folate deprivation especially increased the frequency of nuclear buds and micronuclei harboring telomeric DNA and nuclear buds harboring interstitial DNA but also buds and micronuclei with both centromeric and telomeric DNA. According to the model we propose, that micronuclei in binucleate lymphocytes primarily derive from lagging chromosomes and terminal acentric fragments during mitosis. Most nuclear buds, however, are suggested to originate from interstitial or terminal acentric fragments, possibly representing nuclear membrane entrapment of DNA that has been left in cytoplasm after nuclear division or excess DNA that

  6. Cytogenetic Low-Dose Hyperradiosensitivity Is Observed in Human Peripheral Blood Lymphocytes

    Seth, Isheeta [Department of Biological Sciences, Wayne State University, Detroit, Michigan (United States); Joiner, Michael C. [Department of Radiation Oncology, Wayne State University, Detroit, Michigan (United States); Tucker, James D., E-mail: jtucker@biology.biosci.wayne.edu [Department of Biological Sciences, Wayne State University, Detroit, Michigan (United States)

    2015-01-01

    Purpose: The shape of the ionizing radiation response curve at very low doses has been the subject of considerable debate. Linear-no-threshold (LNT) models are widely used to estimate risks associated with low-dose exposures. However, the low-dose hyperradiosensitivity (HRS) phenomenon, in which cells are especially sensitive at low doses but then show increased radioresistance at higher doses, provides evidence of nonlinearity in the low-dose region. HRS is more prominent in the G2 phase of the cell cycle than in the G0/G1 or S phases. Here we provide the first cytogenetic mechanistic evidence of low-dose HRS in human peripheral blood lymphocytes using structural chromosomal aberrations. Methods and Materials: Human peripheral blood lymphocytes from 2 normal healthy female donors were acutely exposed to cobalt 60 γ rays in either G0 or G2 using closely spaced doses ranging from 0 to 1.5 Gy. Structural chromosomal aberrations were enumerated, and the slopes of the regression lines at low doses (0-0.4 Gy) were compared with doses of 0.5 Gy and above. Results: HRS was clearly evident in both donors for cells irradiated in G2. No HRS was observed in cells irradiated in G0. The radiation effect per unit dose was 2.5- to 3.5-fold higher for doses ≤0.4 Gy than for doses >0.5 Gy. Conclusions: These data provide the first cytogenetic evidence for the existence of HRS in human cells irradiated in G2 and suggest that LNT models may not always be optimal for making radiation risk assessments at low doses.

  7. Glia maturation factor gamma regulates the migration and adherence of human T lymphocytes

    Lippert Dustin ND

    2012-04-01

    Full Text Available Abstract Background Lymphocyte migration and chemotaxis are essential for effective immune surveillance. A critical aspect of migration is cell polarization and the extension of pseudopodia in the direction of movement. However, our knowledge of the underlying molecular mechanisms responsible for these events is incomplete. Proteomic analysis of the isolated leading edges of CXCL12 stimulated human T cell lines was used to identify glia maturation factor gamma (GMFG as a component of the pseudopodia. This protein is predominantly expressed in hematopoietic cells and it has been shown to regulate cytoskeletal branching. The present studies were undertaken to examine the role of GMFG in lymphocyte migration. Results Microscopic analysis of migrating T-cells demonstrated that GMFG was distributed along the axis of movement with enrichment in the leading edge and behind the nucleus of these cells. Inhibition of GMFG expression in T cell lines and IL-2 dependent human peripheral blood T cells with shRNAmir reduced cellular basal and chemokine induced migration responses. The failure of the cells with reduced GMFG to migrate was associated with an apparent inability to detach from the substrates that they were moving on. It was also noted that these cells had an increased adherence to extracellular matrix proteins such as fibronectin. These changes in adherence were associated with altered patterns of β1 integrin expression and increased levels of activated integrins as detected with the activation specific antibody HUTS4. GMFG loss was also shown to increase the expression of the β2 integrin LFA-1 and to increase the adhesion of these cells to ICAM-1. Conclusions The present studies demonstrate that GMFG is a component of human T cell pseudopodia required for migration. The reduction in migration and increased adherence properties associated with inhibition of GMFG expression suggest that GMFG activity influences the regulation of integrin mediated

  8. Cytogenetic damages induced in vivo in human lymphocytes by environmental chemicals or radiation

    Cebulska-Wasilewska, A.

    1999-01-01

    The importance of various environmental exposures has been evident in variation in cancer incidence and mortality. Benzene is considered to be a human carcinogen, is clastogenic to rodents and humans, and it affects the immune response. Workers in various industrial plants, are exposed to benzene and benzene related compounds as a result of various activities in which benzene is processed, generated or used. Major sources of environmental exposure to benzene related compounds, continue to be active and passive smoking, auto exhaust, and driving or riding in automobiles. Benzene is of a particular interest, not only because of its known toxicity, but also because this was to be the parent compound and a model for extensive programs of metabolism of a variety of aromatic chemicals. Ionizing radiation is an unavoidable physical agent that is presented in environment, and public opinion is well aware against radiation risk and strongly against it. The aim of the presentation was comparison between cytogenetic damages induced in vivo by environmental chemicals with those of radiation. Results from biomonitoring survey on genotoxicity in human blood cells of benzene and benzene related compounds were compared to damages detected in lymphocytes of persons who had been accidentally exposed to gamma radiation. In the groups, that had been occupationally or environmentally exposed to benzene related compound, total aberration frequencies, or percent of aberrant cells ranged between 0 - 0.16 aberrations/cell or 16% of aberrant cells respectively. A multivariate regression analysis confirmed: (i) a significant association between cytogenetic damage and exposure to benzene related compound, (ii) a possible association between cytogenetic damage and cancer, (iii) a significant influence of smoking habit. In 1996 few persons were suspected of accidental exposure to gamma radiation. To estimate the absorbed doses, lymphocytes from their blood have been analyzed for the presence of

  9. An incubation medium for the elevation of adenosine triphosphate and 2,3-diphosphoglycerate in fresh and long-preserved human erythrocytes.

    Rubinstein, D; Warrendorf, E

    1975-06-01

    The levels of adenosine triphosphate (ATP) and 2,3-diphosphoglycerate in freshly drawn human erythrocytes can be tripled by a 2 h incubation at 37 degrees C in a medium containing 21 mM glucose, 1.8 mM adenine, 5 mM pyruvate, 10 mM inosine, and 96 mM phosphate. Similar incubation conditions will restore the levels of ATP and 2,3-diphosphoglycerate in erythrocytes from blood levels preserved for 12 and 15 weeks, respectively, to those of fresh cells. Omission of pyruvate from the incubation medium further increases the level of ATP slightly, but there is little elevation of 2,3-diphosphoglycerate. Under these conditions labelled pyruvate and lactate production from [14-C]glucose or [14-C]inosine is not diminished, but labelled fructose 1,6-diphosphate, rather than 2,3-diphosphoglycerate, accumulates. In addition, omission of pyruvate from the incubation medium, with a concomitant decrease in accumulation of 2,3-diphosphoglycerate, diminishes the concentration of inorganic phosphate required for optimal ATP elevation. A 5 h incubation in the glucose-adenine-pyruvate-inosine-phosphate medium elevates the levels of ATP and 2,3-diphosphoglycerate in erythrocytes from blood preserved in the cold for 15 weeks to twice that of fresh cells, indicating that the cells retain their metabolic potential even after prolonged storage at 2 degrees C. The medium may provide a method of rejuvenating 10-12 week cold-preserved erythrocytes for transfusion purposes, by a 1 h incubation at 37 degrees C.

  10. Physical-chemical basis of the protection of slowly frozen human erythrocytes by glycerol

    Rall, W.F.; Mazur, P.; Souzu, H.

    1978-07-01

    One theory of freezing damage suggests that slowly cooled cells are killed by being exposed to increasing concentrations of electrolytes as the suspending medium freezes. A corollary to this view is that protective additives such as glycerol protect cells by acting colligatively to reduce the electrolyte concentration at any subzero temperature. Recently published phase-diagram data for the ternary system glycerol-NaCl-water by M.L. Shepard et al. (Cryobiology, 13: 9-23, 1976), in combination with the data on human red cell survival vs. subzero temperature presented here and in the companion study of Souzu and Mazur (Biophys. J., 23: 89-100), permit a precise test of this theory. Appropriate liquidus phase-diagram information for the solutions used in the red cell freezing experiments was obtained by interpolation of liquidus data of Shepard and his co-workers. The results of phase-diagram analysis of red cell survival indicate that the correlation between the temperature that yields 50% hemolysis (LT/sub 50/) and the electrolyte concentration attained at that temperature in various concentrations of glycerol is poor. With increasing concentrations of glycerol, the cells were killed at progressively lower concentrations of NaCl. For example, the LT/sub 50/ for cells frozen in the absence of glycerol corresponds to a NaCl concentration of 12 weight percent (2.4 molal), while for cells frozen in 1.75 M glycerol in buffered saline the LT/sub 50/ corresponds to 3.0 weight percent NaCl (1.3 molal). The data, in combination with other findings, lead to two conclusions: (a) The protection from glycerol is due to its colligative ability to reduce the concentration of sodium chloride in the external medium, but (b) the protection is less than that expected from colligative effects; apparently glycerol itself can also be a source of damage, probably because it renders the red cells susceptible to osmotic shock during thawing.

  11. [Effects of oil-refining microbes (genus Acinetobacter) on cytogenetical structures of human lymphocytes in cell cultures].

    Il'inskikh, N N; Il'inskikh, E N; Il'inskikh, I N

    2012-01-01

    The objective of this study was to assess ability of oil-refining bacteria Acinetobacter calcoaceticus and A. valentis to induce karyopathological abnormalities and chromosomal aberrations in human lymphocyte cultures. It was found that the cultures infected with A. calcoaceticus showed significantly high frequencies of cytogenetical effects and chromosomal aberrant cells as compared to the intact cultures and cultures infected with A. valentis. The most of chromosomal aberrations, mainly chromatid aberrations, were located in 1 and 2 chromosomes. Moreover, the aberrations were detected in some specific chromosome areas. Abnormalities of mitotic cell division and nucleus morphology were determined in lymphocyte cultures infected with A. calcoaceticus. There were found significantly high frequencies of cells with micronuclei, nucleus protrusions, anaphase or metaphase chromosome and chromosomal fragments lagging as well as multipolar and C-mitoses. Thus, the oil-refining bacteria A. calcoaceticus in contrast to A. valentis demonstrated strong genotoxic effects in human lymphocyte cultures in vitro.

  12. Human erythrocytes bind and inactivate type 5 adenovirus by presenting Coxsackie virus-adenovirus receptor and complement receptor 1

    Carlisle, R. C.; Di, Y.; Cerny, A. M.; Sonnen, A. F. P.; Sim, R. B.; Green, N. K.; Šubr, Vladimír; Ulbrich, Karel; Gilbert, R. J. C.; Fisher, K. D.; Finberg, R. W.; Seymour, L. W.

    2009-01-01

    Roč. 113, č. 9 (2009), s. 1909-1918 ISSN 0006-4971 EU Projects: European Commission(XE) 512087 - GIANT Institutional research plan: CEZ:AV0Z40500505 Keywords : adenovirus * erythrocyte * complement receptor 1 Subject RIV: CD - Macromolecular Chemistry Impact factor: 10.555, year: 2009

  13. Measurement of in vivo HGPRT-deficient mutant cell frequency using a modified method for cloning human peripheral blood T-lymphocytes

    Hakoda, Masayuki; Akiyama, Mitoshi; Kyoizumi, Seishi; Kobuke, Kyoko; Awa, A.A.

    1987-07-01

    Approximately 80 % of human peripheral blood T-lymphocytes could be cloned in the presence of crude Interleukin-2, phytohemagglutinin, and X-irradiated autologous lymphocytes and Raji B-cells. This modified cloning method was used to measure the in vivo frequency of HGPRT-deficient mutant T-lymphocytes. Repeated experiments using blood from the same individuals revealed that the frequency of mutant cells was almost constant for each individual even though the cloning efficiency of lymphocytes varied somewhat from experiment to experiment. Approximately 80 % of both wild-type unselected and 6-thioguanine-resistant colonies had helper/inducer and about 20 % had suppressor/cytotoxic T-lymphocyte markers. No difference was observed in the distribution of lymphocyte subsets between wild and mutant lymphocyte colonies. (author)

  14. Therapeutic activity of two xanthones in a xenograft murine model of human chronic lymphocytic leukemia

    Berthou Christian

    2010-12-01

    Full Text Available Abstract Background We previously reported that allanxanthone C and macluraxanthone, two xanthones purified from Guttiferae trees, display in vitro antiproliferative and proapoptotic activities in leukemic cells from chronic lymphocytic leukemia (CLL and leukemia B cell lines. Results Here, we investigated the in vivo therapeutic effects of the two xanthones in a xenograft murine model of human CLL, developed by engrafting CD5-transfected chronic leukemia B cells into SCID mice. Treatment of the animals with five daily injections of either allanxanthone C or macluraxanthone resulted in a significant prolongation of their survival as compared to control animals injected with the solvent alone (p = 0.0006 and p = 0.0141, respectively. The same treatment of mice which were not xenografted induced no mortality. Conclusion These data show for the first time the in vivo antileukemic activities of two plant-derived xanthones, and confirm their potential interest for CLL therapy.

  15. Chromosome aberrations induced by low doses of X-rays in human lymphocytes in vitro

    Ziemba-Zoltowska, B.; Bocian, E.; Rosiek, O.; Sablinski, J.

    1980-01-01

    Curves derived from the dose-response data for the yield of aberrations in human lymphocytes can be represented by a quadratic equation at all but low dose ranges. A calibration curve has therefore been determined at a low dose range of X-radiation (11.5 to 57.5 rad). The frequencies of dicentrics plus centric rings, and of acentrics were better fitted by linear dose-response models than quadratic. The linearity of the relationship indicated that asymmetrical chromosome exchanges at low doses of radiation are produced predominantly by a single track mechanism. A dose-response curve for dicentrics plus centric rings (5 to 60 rad) has also been derived by pooling published data with the results of this study. This calibration curve is relevant to cytogenetic dosimetry in radiological protection. (UK)

  16. The changes of production of lymphokines from gamma irradiated human tonsillar lymphocytes: Pt. 2

    Miao Jingcheng; Zhang Lansheng

    1989-02-01

    The human tonsillar lymphocytes were exposed to gamma rays in various doses (0 ∼ 40 Gy) and stimulated by PHA, then cultured for 24 to 96 hours. The activities of NKCF in the supernatants were assayed by MTT colorimetric method. The results showed: (1) The activity of NKCF was slightly inhibited by irradiation of 2.5 ∼ 40 Gy; (2) The activity of NKCF in the supernatants cultured for 48 to 96 hours is obviously higher than that for 24 hours. Both the irradiatiion doses and cultural periods had no interactiion on the changes of the production of NKCF. The radiation resistance of NK cells in the experiment is similar to other results. The tonsillar Nk cells activated in the state of chronic inflamation has higher radioresistance

  17. In Vitro Genotoxic Effects of Four Helichrysum Species in Human Lymphocytes Cultures

    Erhan H Erolu

    2010-01-01

    Full Text Available Helichrysum sanguineum, Helichrysum pamphylicum, Helichrysum orientale, Helichrysum noeanum (Asteraceae are medicinal plants. For centuries, they have been used as tea in Turkey because of their medicinal properties. So far no scientifc evidence has been found in a literature survey regarding the genotoxic effects of these plants. This work evaluated the genotoxic effects on human lymphocyte cultures induced by methanol extracts of these plants, assayed in different concentrations (0.01, 0.05, 0.1, 0.5 and 1 mg/mL. According to the results, Helichrysum noeanum, Helichrysum pamphylicum and Helichrysum sanguineum induced the formation of micronuclei and decreased the mitotic and replication indexes. Helichrysum orientale did not affect these parameters, whereas Helichrysum noeanum, Helichrysum pamphylicum and Helichrysum sanguineum were clearly genotoxic. They should therefore not be used freely in alternative medicine, although their antiproliferative activity may suggest antimitotic and anticarcinogenic properties. Helichrysum orientale could be used in alternative medicine.

  18. In vitro genotoxic effects of four Helichrysum species in human lymphocytes cultures.

    Erolu, Erhan H; Hamzaolu, Ergin; Aksoy, Ahmet; Budak, Ümit; Özkul, Yusuf

    2010-01-01

    Helichrysum sanguineum, Helichrysum pamphylicum, Helichrysum orientale, Helichrysum noeanum (Asteraceae) are medicinal plants. For centuries, they have been used as tea in Turkey because of their medicinal properties. So far no scientific evidence has been found in a literature survey regarding the genotoxic effects of these plants. This work evaluated the genotoxic effects on human lymphocyte cultures induced by methanol extracts of these plants, assayed in different concentrations (0.01, 0.05, 0.1, 0.5 and 1 mg/mL). According to the results, Helichrysum noeanum, Helichrysum pamphylicum and Helichrysum sanguineum induced the formation of micronuclei and decreased the mitotic and replication indexes. Helichrysum orientale did not affect these parameters, whereas Helichrysum noeanum, Helichrysum pamphylicum and Helichrysum sanguineum were clearly genotoxic. They should therefore not be used freely in alternative medicine, although their antiproliferative activity may suggest antimitotic and anticarcinogenic properties. Helichrysum orientale could be used in alternative medicine.

  19. Relation between cell cycle and yield of aberrations observed in irradiated human lymphocytes

    Leonard, A.; Decat, G.

    1979-01-01

    The bromodeoxyuridine-Giemsa technique has been used to study systematically the incidence of cells in first or subsequent mitoses at differrent fixation times of human lymphocyte control cultures as well as the influence of ionizing radiations on cell kinetics. Second divisions appear (3%) in cultures harvested 48 h after initiation. In 72 h cultures 40% of the dividing cells are in second and 33% in third division. Administration of 200 rads of X-rays before PHA stimulation results in a mitotic delay but does not increase the incidence of SCE. The yield of dicentrics after an exposure to 200 rads was the same for all cells in first mitosis regardless of fixation time. These results demonstrate that there is no evidence for the existence of sensitive subpopulations that could be distinguished by the time of the first mitotic division following stimulation. (author)

  20. Chromosome dosimetry: the influence of culture media on the proliferation of irradiated and unirradiated human lymphocytes

    Purrott, R.J.; Lloyd, D.C.; Vulpis, N.

    1981-01-01

    The proliferation of phytohaemagglutinin stimulated human lymphocytes in four types of synthetic culture medium has been studied using the fluorescence plus Giemsa staining technique to determine cell cycle status. 48 hour cultures of unirradiated cells containing Ham's F10 or RPMI 1640 media yielded significant numbers of second cycle metaphases. Cultures containing Eagle's MEM or TC 199 media, however, required longer incubation times to produce appreciable numbers of second division cells. Intrinsic differences between donors in the rate of proliferation had little effect on the relative ranking of the media. Radiation induced mitotic delay of about 1 hour per Gray was observed for each medium. The relevance of these results to the accuracy of radiation dose estimation by chromosome aberration analysis is discussed. (author)

  1. Extract from Armoracia rusticana and Its Flavonoid Components Protect Human Lymphocytes against Oxidative Damage Induced by Hydrogen Peroxide

    Michala Gafrikova; Eliska Galova; Andrea Sevcovicova; Petronela Imreova; Pavel Mucaji; Eva Miadokova

    2014-01-01

    DNA damage prevention is an important mechanism involved in cancer prevention by dietary compounds. Armoracia rusticana is cultivated mainly for its roots that are used in the human diet as a pungent spice. The roots represent rich sources of biologically active phytocompounds, which are beneficial for humans. In this study we investigated the modulation of H2O2 genotoxicity using the A. rusticana root aqueous extract (AE) and two flavonoids (kaempferol or quercetin). Human lymphocytes pre-t...

  2. Expression, processing and transcriptional regulation of granulysin in short-term activated human lymphocytes

    Groscurth Peter

    2007-06-01

    Full Text Available Abstract Background Granulysin, a cytotoxic protein expressed in human natural killer cells and activated T lymphocytes, exhibits cytolytic activity against a variety of intracellular microbes. Expression and transcription have been partially characterised in vitro and four transcripts (NKG5, 519, 520, and 522 were identified. However, only a single protein product of 15 kDa was found, which is subsequently processed to an active 9 kDa protein. Results In this study we investigated generation of granulysin in lymphokine activated killer (LAK cells and antigen (Listeria specific T-cells. Semiquantitative RT-PCR revealed NKG5 to be the most prominent transcript. It was found to be up-regulated in a time-dependent manner in LAK cells and antigen specific T-cells and their subsets. Two isoforms of 519 mRNA were up-regulated under IL-2 and antigen stimulation. Moreover, two novel transcripts, without any known function, comprising solely parts of the 5 prime region of the primary transcript, were detected. A significant increase of granulysin expressing LAK cells as well as antigen specific T-cells was shown by fluorescence microscopy. On the subset level, increase in CD4+ granulysin expressing cells was found only under antigen stimulation. Immunoblotting showed the 15 kDa form of granulysin to be present in the first week of stimulation either with IL-2 or with bacterial antigen. Substantial processing to the 9 kDa form was detected during the first week in LAK cells and in the second week in antigen specific T-cells. Conclusion This first comprehensive study of granulysin gene regulation in primary cultured human lymphocytes shows that the regulation of granulysin synthesis in response to IL-2 or bacterial antigen stimulation occurs at several levels: RNA expression, extensive alternative splicing and posttranslational processing.

  3. Voltage-gated potassium channels regulate calcium-dependent pathways involved in human T lymphocyte activation.

    Lin, C S; Boltz, R C; Blake, J T; Nguyen, M; Talento, A; Fischer, P A; Springer, M S; Sigal, N H; Slaughter, R S; Garcia, M L

    1993-03-01

    The role that potassium channels play in human T lymphocyte activation has been investigated by using specific potassium channel probes. Charybdotoxin (ChTX), a blocker of small conductance Ca(2+)-activated potassium channels (PK,Ca) and voltage-gated potassium channels (PK,V) that are present in human T cells, inhibits the activation of these cells. ChTX blocks T cell activation induced by signals (e.g., anti-CD2, anti-CD3, ionomycin) that elicit a rise in intracellular calcium ([Ca2+]i) by preventing the elevation of [Ca2+]i in a dose-dependent manner. However, ChTX has no effect on the activation pathways (e.g., anti-CD28, interleukin 2 [IL-2]) that are independent of a rise in [Ca2+]i. In the former case, both proliferative response and lymphokine production (IL-2 and interferon gamma) are inhibited by ChTX. The inhibitory effect of ChTX can be demonstrated when added simultaneously, or up to 4 h after the addition of the stimulants. Since ChTX inhibits both PK,Ca and PK,V, we investigated which channel is responsible for these immunosuppressive effects with the use of two other peptides, noxiustoxin (NxTX) and margatoxin (MgTX), which are specific for PK,V. These studies demonstrate that, similar to ChTX, both NxTX and MgTX inhibit lymphokine production and the rise in [Ca2+]i. Taken together, these data provide evidence that blockade of PK,V affects the Ca(2+)-dependent pathways involved in T lymphocyte proliferation and lymphokine production by diminishing the rise in [Ca2+]i that occurs upon T cell activation.

  4. In vitro exposure to X-radiation of stimulated and non-stimulated human B lymphocytes and T lymphocytes. In vitro Roentgenbestrahlung stimulierter und unstimulierter menschlicher B- und T-Lymphozyten

    Krystossek, H.

    1986-09-25

    The sensitivity of human type B and type T lymphocytes to 130 kV X-radiation was investigated in vitro. The degree to which 3H thymidine was incorporated into the DNA of these cells was taken as a measure of cellular viability. The results led to the conclusion that the in vitro reactions to X-rays following stimulation and radiation are considerably more pronounced in human B lymphocytes than in human T lymphocytes. The rapid radiation-induced lessening of thymidine incorporation into stimulated B lymphocytes was interpreted as a sign that cellular decay occurred during the interphase. The relative increases in the thymidine incorporation rates seen following radiation of T cells in the presence of hydroxyurea or caffeinemust, however, not be mistaken for an augmentation of resistance that was brought about by these inhibitors. The latter effect is believed to be rather due to an overreaction of the repair mechanisms of DNA which is characterised by short chains.

  5. Effects of low concentrations of cadmium on immunoglobulin E production by human B lymphocytes in vitro

    Jelovcan, Sandra; Gutschi, Andrea; Kleinhappl, Barbara; Sedlmayr, Peter; Barth, Sonja; Marth, Egon

    2003-01-01

    Exposure to cadmium (Cd) can cause a variety of biological effects including alterations of immune responses in animals and humans. Both immunosuppression and immunoenhancement have been reported. The present study was aimed at investigating the consequences of exposure to Cd on the human immunoglobulin (Ig) E synthesis, using purified peripheral blood B lymphocytes and IL-4 and anti-human CD40 monoclonal antibody (a-CD40 mAb) as stimuli. Low concentrations of Cd (0.1-10 μM) markedly inhibited production of IgE in a concentration-dependent manner. IgG production, in contrast to IgE, showed a tendency towards being enhanced by Cd, although with a certain individual variability; IgM production was not affected. Cd failed to alter immediate surface expression of the activation markers CD69 and CD23 indicating that early activation events were not impaired. However, the portion of activated B cells was diminished by Cd after stimulation for more than 24 h, paralleled by a concomitant decrease in viability and a subsequent reduction in proliferation. These data suggest that the mechanism of Cd action on activated B cells involved pathways that interrupted an effectively initiated cell activation and induced a cytotoxic signal. Results from this study thus provide further evidence for and new information on the immunotoxic and immunomodulatory effects of Cd on human immune responses

  6. Factors influencing erythrocyte choline concentrations.

    Miller, B L; Jenden, D J; Tang, C; Read, S

    1989-01-01

    Choline concentrations in human erythrocytes increase after freezing and thawing, during incubation in Krebs-phosphate for 30 min or on storage at 0 degrees C for 3-24 hr. The increase is prevented by protein precipitation by 10% perchloric acid, 10% zinc hydroxide, 10% sodium tungstate or boiling in water. It is not prevented by EDTA (10 mM) and is increased by oleate (5 mM). We suggest that the increase is due to the action of phospholipase D on erythrocyte phospholipids.

  7. Nitric oxide selectively decreases interferon-gamma expression by activated human T lymphocytes via a cGMP-independent mechanism

    Roozendaal, R; Vellenga, E; Postma, DS; De Monchy, JGR; Kauffman, HF

    1999-01-01

    The role of exogenous nitric oxide (NO) on the expression of interleukin (IL)-2, IL-4, IL-5 and interferon-gamma (IFN-gamma) by freshly isolated human T lymphocytes was investigated. The presence of NO, generated from any of the NO-donor compounds, S-nitroso-N-acetyl-D,L-penicillamine (NAP),

  8. Comparative analysis of chromosome aberrations induced in human lymphocytes in vitro by various types of ionizing radiations

    Todorov, S.L.

    1979-01-01

    Certain problems of comparative analyses of radiation-induced dicentrics in human lymphocytes following various types of ionizing radiations are considered as follows: 1. Equations best fitting for dose-response kinetics; 2. Use of dicentrics for analysing the RBE of various types of radiations; 3. The relationship between RBE and LET as seen by the analysis of dicentrics. (author)

  9. Solar-simulated ultraviolet irradiation induces selective influx of CD4+ T lymphocytes in normal human skin

    Di Nuzzo, S.; de Rie, M. A.; van der Loos, C. M.; Bos, J. D.; Teunissen, M. B.

    1996-01-01

    The proportion and composition of the human cutaneous CD3+ T lymphocyte population was determined in situ following a single exposure to physiological, erythema-inducing doses of simulated solar radiation, mainly consisting of UV radiation. Biopsies were taken 1, 2 and 7 days after local irradiation

  10. Cytokine production by natural killer lymphocytes in follicular and luteal phase of the ovarian cycle in humans

    Bouman, A.; Moes, H; Heineman, MJ; De Leij, LFMH; Faas, MM

    PROBLEM: The aim of this study was to test the hypothesis that, during luteal phase of the ovarian cycle, as compared with follicular phase, the cytokine productive capacity of peripheral natural killer (NK)-lymphocytes in humans is shifted towards a "Th2-type"-like response. METHOD OF STUDY:

  11. Interleukin-15 differentially enhances the expression of interferon-gamma and interleukin-4 in activated human (CD4(+))T lymphocytes

    Borger, P; Kauffman, HF; Postma, DS; Esselink, MT; Vellenga, E

    In this study interleukin (IL)-15 was examined for its ability to modulate the expression of interferon-gamma (IFN-gamma) and IL-4 in activated human T lymphocytes. The effect of IL-15 was compared with IL-2 and IL-7, cytokines all known to use the IL-2 receptor gamma(C) chain. The results

  12. RhD Specific Antibodies Are Not Detectable in HLA-DRB11501* Mice Challenged with Human RhD Positive Erythrocytes

    Lidice Bernardo

    2014-01-01

    Full Text Available The ability to study the immune response to the RhD antigen in the prevention of hemolytic disease of the fetus and newborn has been hampered by the lack of a mouse model of RhD immunization. However, the ability of transgenic mice expressing human HLA DRB11501* to respond to immunization with purified RhD has allowed this question to be revisited. In this work we aimed at inducing anti-RhD antibodies by administering human RhD+ RBCs to mice transgenic for the human HLA DRB11501* as well as to several standard inbred and outbred laboratory strains including C57BL/6, DBA1/J, CFW(SW, CD1(ICR, and NSA(CF-1. DRB11501* mice were additionally immunized with putative extracellular immunogenic RhD peptides. DRB11501* mice immunized with RhD+ erythrocytes developed an erythrocyte-reactive antibody response. Antibodies specific for RhD could not however be detected by flow cytometry. Despite this, DRB11501* mice were capable of recognizing immunogenic sequences of Rh as injection with Rh peptides induced antibodies reactive with RhD sequences, consistent with the presence of B cell repertoires capable of recognizing RhD. We conclude that while HLA DRB11501* transgenic mice may have the capability of responding to immunogenic sequences within RhD, an immune response to human RBC expressing RhD is not directly observed.

  13. Radiosensitivities of sensitized lymphocytes

    Taniguchi, Kazuto

    1979-01-01

    Immunization of mice with cell antigens such as allogeneic tumor cells or xenogeneic erythrocytes raises a variety of immune reactions mediated by T lymphocytes: i.e. delayed type hypersensitivity (DTH), cytotoxicity, and antibody production. The radiosensitivities of these reactions were examined in mice exposed to 600 R x-irradiation a few hours before or after immunization. 1) DTH to xenogeneic erythrocytes, as demonstrated by footpad reaction, was not suppressed by irradiation 3 h before or after immunization. DTH to allogeneic tumor cells, as demonstrated by a migration inhibition test, hardly developed in mice that had been irradiated before or after immunization. It may have belonged to distinct types of delayed reactions which were mediated by distinct subpopulations of T lymphocytes. 2) Cytotoxicity against allogeneic cells and xenogeneic erythrocytes showed almost the same radiosensitivity. It was scarcely detected in mice that had been irradiated before immunization. However, a low but definite degree of cytotoxicity was detected in mice that had been irradiated only a few hours after immunization. Solubilized allogeneic cells instead of native cells were used as immunizing antigens. It was also possible for precursor cells with cytotoxicity to acquire a radioresistant nature by immunization of solubilized antigens, but native cells were required as stimulation for radioresistant precursor cells to differentiated into nature cytotoxic effector cells. 3) Antibody production against xenogeneic erythrocytes or allogeneic cells was almost completely depleted in mice that had been irradiated before or after immunization. It is possible that antibody production essentially requires cell division and clonal expansion of B lymphocytes. (Bell, E.)

  14. Effect of caffeine posttreatment on X-ray-induced chromosomal aberrations in human blood lymphocytes in vitro

    Natarajan, A T [Rijksuniversiteit Leiden (Netherlands). Dept. of Radiation Genetics and Chemical Mutagenesis; Cohen (J.A.) Inst. voor Radiopathologie en Stralenbescherming, Leiden (Netherlands)); Obe, G [Rijksuniversiteit Leiden (Netherlands). Dept. of Radiation Genetics and Chemical Mutagenesis; Cohen (J.A.) Inst. voor Radiopathologie en Stralenbescherming, Leiden (Netherlands); Freie Univ. Berlin (Germany, F.R.). Inst. fuer Genetik); Dulout, F N [Rijksuniversiteit Leiden (Netherlands). Dept. of Radiation Genetics and Chemical Mutagenesis; Instituto Multidisciplinario de Biologia Celular, La Plata (Argentinia))

    1980-01-01

    The potentiating effect of caffeine on X-ray-induced chromosomal aberrations in human blood lymphocytes has been investigated, with special reference to cell cycle stages (G0 and G2). Both quantitative and qualitative differences in the yield of chromosomal aberrations were detected in caffeine-posttreated cells, depending on the cell stage irradiated. The studies on caffeine potentiating effects on X-irradiated G0 lymphocytes from normal adults, newborns, Down syndrome patients, and an ataxia telangiectasia patient pointed to interindividual variations in the response to caffeine potentiation among normal probands and a very profound effect in ataxia cells.

  15. The effect of caffeine posttreatment on X-ray-induced chromosomal aberrations in human blood lymphocytes in vitro

    Natarajan, A.T.; Obe, G.

    1980-01-01

    The potentiating effect of caffeine on X-ray-induced chromosomal aberrations in human blood lymphocytes has been investigated, with special reference to cell cycle stages (G0 and G2). Both quantitative and qualitative differences in the yield of chromosomal aberrations were detected in caffeine-posttreated cells, depending on the cell stage irradiated. The studies on caffeine potentiating effects on X-irradiated G0 lymphocytes from normal adults, newborns, Down syndrome patients, and an ataxia telangiectasia patient pointed to interindividual variations in the response to caffeine potentiation among normal probands and a very profound effect in ataxia cells. (orig.) [de

  16. The study of chromosome aberration yield in human lymphocytes as an indicator of radiation dose. 1. Techniques

    Purrott, R.J.; Lloyd, D.C.

    1972-08-01

    Estimates of exposure to ionizing radiation can be obtained by determining the yield of chromosome aberrations in cultured human lymphocytes. Chromosomes can only be conveniently examined during cell division. The lymphocytes, which do not normally divide whilst circulating, are stimulated to divide during a 48-hour culture period. Two types of culture technique are described, one of which employs a lymphocyte-enriched inoculum and the other which uses whole blood. After culture the cells are harvested, dispensed onto slides and prepared for microscopic examination. An account is also given of the analysis of various types of radiation-induced chromosome aberrations and of the construction of calibration curves for certain types and rates of radiation which are used to interpret the aberration yields in terms of dose. (author)

  17. Sensitivity of human peripheral lymphocyte chromosomes to various X-ray doses and subsequent storage in Plexiglass or glass containers

    Ivanov, B.; Bulanova, M.; Geogieva, I.

    1979-01-01

    A study was performed to determine whether chromosomal aberrations produced in vitro by various X-ray doses in human lymphocytes were affected by post-irradiation storage of the blood in plastic or glass containers. Following X-ray doses of up to 400 R, the yields of cells with aberrations and the incidence of dicentrics, rings, interstitial deletions, symmetrical changes and chromosome fragments increased with dose. After storage of the irradiated lymphocytes in either Plexiglass or glass, the values for exchange aberrations, deletions and aberrant cells were compared. The only statistically significant difference was a slight increase in the percentage of aberrant cells stored in the plastic containers at the 400 R dose level. It was concluded that plastics appear to have a sensitizing effect on the genetic structure of the peripheral lymphocyte and thus the use of this material to store blood in biological dosimetry studies should be discouraged. (U.K.)

  18. The effect of cryo-storage on the beta 2-adrenoceptor density and responsiveness in intact human lymphocytes

    Ahlquist, P; Johansen, Torben; Friis, U G

    1994-01-01

    This study evaluates the effect of cryo-storage on beta 2-adrenoceptor number and formation of adenosine 3':5'-cyclic monophosphate (cAMP) in intact human lymphocytes as a measure of the beta 2-adrenoceptor responsiveness. Cryo-storage at -196 degrees C up to 12 months caused no significant......), but changed significantly after long-term storage (3-12 months). We can conclude that lymphocytes can be stored for months for later determination of beta-adrenoceptors. The cryo-storage method described in this paper are, however, only useful for measurements of very large changes in cAMP formation, and our...... results indicate that the method should be further modified in order to preserve the lymphocyte responsiveness after cryo-storage....

  19. Frequency and distribution analysis of chromosomal translocations induced by x-ray in human lymphocytes

    Lopez Hidalgo, Juana Ines

    2000-01-01

    The characteristic of ionizing radiation suggests that induced chromosomal damage in the form of translocations would appear to be randomly distributed. However, the outcome of tests performed in vitro and in vivo (irradiated individuals) are contradictories. The most translocation-related chromosomes, as far as some studies reveal on one hand, appear to be less involved in accordance with others. These data, together with those related to molecular mechanisms involved in translocations production suggest that in G 0 -irradiated cells, the frequency and distribution of this kind of chromosomal rearrangement, does not take place at random. They seem to be affected by in-nucleus chromosome distribution, by each chromosome's DNA length and functional features, by the efficiency of DNA repair mechanisms, and by inter individual differences. The objective of this study was to establish the frequency pattern of each human chromosome involved in radio-induced translocations, as well as to analyze the importance the chromosome length, the activity of DNA polymerase- dependant repair mechanisms, and inter individual differences within the scope of such distribution. To achieve the goals, peripheral blood lymphocytes from healthy donors were irradiated in presence and absence of 2'-3' dideoxithimidine (ddThd), a Β - DNA polymerase inhibitor, which takes part in the base repair mechanism (B E R). The results showed that: The presence of ddThd during the irradiation increase the basal frequency of radioinduced translocations in 60 %. This result suggests that ddThd repair synthesis inhibition can be in itself a valid methodology for radiation-induced bases damage assessment, damage which if not BER-repaired may result in translocation-leading double strand breaks. A statistically significant correlation between translocation frequency and chromosome length, in terms of percentage of genome, has been noticed both in (basal) irradiation and in irradiation with ddThd inhibitor

  20. Non-codingRNA sequence variations in human chronic lymphocytic leukemia and colorectal cancer.

    Wojcik, Sylwia E; Rossi, Simona; Shimizu, Masayoshi; Nicoloso, Milena S; Cimmino, Amelia; Alder, Hansjuerg; Herlea, Vlad; Rassenti, Laura Z; Rai, Kanti R; Kipps, Thomas J; Keating, Michael J; Croce, Carlo M; Calin, George A

    2010-02-01

    Cancer is a genetic disease in which the interplay between alterations in protein-coding genes and non-coding RNAs (ncRNAs) plays a fundamental role. In recent years, the full coding component of the human genome was sequenced in various cancers, whereas such attempts related to ncRNAs are still fragmentary. We screened genomic DNAs for sequence variations in 148 microRNAs (miRNAs) and ultraconserved regions (UCRs) loci in patients with chronic lymphocytic leukemia (CLL) or colorectal cancer (CRC) by Sanger technique and further tried to elucidate the functional consequences of some of these variations. We found sequence variations in miRNAs in both sporadic and familial CLL cases, mutations of UCRs in CLLs and CRCs and, in certain instances, detected functional effects of these variations. Furthermore, by integrating our data with previously published data on miRNA sequence variations, we have created a catalog of DNA sequence variations in miRNAs/ultraconserved genes in human cancers. These findings argue that ncRNAs are targeted by both germ line and somatic mutations as well as by single-nucleotide polymorphisms with functional significance for human tumorigenesis. Sequence variations in ncRNA loci are frequent and some have functional and biological significance. Such information can be exploited to further investigate on a genome-wide scale the frequency of genetic variations in ncRNAs and their functional meaning, as well as for the development of new diagnostic and prognostic markers for leukemias and carcinomas.

  1. HLA-C is necessary for optimal human immunodeficiency virus type 1 infection of human peripheral blood CD4 lymphocytes.

    Baroni, Miriam; Matucci, Andrea; Scarlatti, Gabriella; Soprana, Elisa; Rossolillo, Paola; Lopalco, Lucia; Zipeto, Donato; Siccardi, Antonio G; De Santis, Claudio

    2010-01-01

    The hypothesis that open conformers of HLA-C on target cells might directly exert an effect on their infectability by human immunodeficiency virus (HIV) has been suggested previously. This was tested by exploiting the peculiar specificity of monoclonal antibody (mAb) L31 for HLA-C open conformers to show that normal levels of Env-driven fusion were restored in HLA-C transfectants of a major histocompatibility complex-deleted (fusion-incompetent) cell line. The physiological relevance of this finding is now confirmed in this report, where small interfering RNA (siRNA) technology was used to silence HLA-C expression in peripheral blood lymphocytes (PBLs) from 11 healthy donors. Infectability by HIV (strains IIIB and Bal and primary isolates) was significantly reduced (P=0.016) in silenced cells compared with cells that maintained HLA-C expression in 10 of the 11 PBL donors. Normal infectability was resumed, together with HLA-C expression, when the effect of siRNA interference waned after several days in culture. Additional confirmation of the HLA-C effect was obtained in several assays employing HLA-C-positive and -negative cell lines, a number of HIV strains and also pseudoviruses. In particular, viruses pseudotyped with env genes from HIV strains AC10 and QH0692.42 were assayed on siRNA-silenced lymphocytes from three healthy donors: the differences in infection with pseudoviruses were even higher than those observed in infections with normal viruses.

  2. T CD3+CD8+ Lymphocytes Are More Susceptible for Apoptosis in the First Trimester of Normal Human Pregnancy

    Dorota Darmochwal-Kolarz

    2014-01-01

    Full Text Available Aims. Normal human pregnancy is a complex process of many immunoregulatory mechanisms which protect fetus from the activation of the maternal immune system. The aim of the study was to investigate the apoptosis of lymphocytes in peripheral blood of normal pregnant patients and healthy nonpregnant women. Methods. Sixty pregnant women and 17 nonpregnant women were included in the study. Lymphocytes were isolated and labeled with anti-CD3, anti-CD4, and anti-CD8 monoclonal antibodies. Apoptosis was detected by CMXRos staining and analyzed using the flow cytometric method. Results. We found significantly higher apoptosis of total lymphocytes in peripheral blood of pregnant patients when compared to healthy nonpregnant women. The percentage of apoptotic T CD3+CD8+ cells in the first trimester was significantly higher when compared to the third trimester of normal pregnancy. The ratio of T CD3+CD4+ : T CD3+CD8+ apoptotic lymphocytes was significantly lower in the first trimester when compared to other trimesters of pregnancy and to both of the phases of the menstrual cycle. Conclusions. The higher apoptosis of T CD3+CD8+ lymphocytes and the lower ratio of T CD3+CD4+ : T CD3+CD8+ apoptotic cells in the first trimester of normal pregnancy may suggest a higher susceptibility of T CD3+CD8+ cells for apoptosis as a protective mechanism at the early stage of pregnancy.

  3. Radiosensitivity of CD4 and CD8 positive human T lymphocytes by an in vitro colony formation assay

    Nakamura, Nori; Kusunoki, Yoichiro; Akiyama, Mitoshi.

    1989-12-01

    The recent development of an in vitro lymphocyte colony assay provides a new opportunity to examine possible variations in human radiosensitivity using peripheral blood lymphocytes (PBL) in place of the hitherto used skin fibroblast assay. Our recent study showed that most of the colonies consisted of lymphocytes bearing CD4 or CD8 antigens. Since the fraction of CD4 + and CD8 + cells in PBL differs among individuals, it was suspected that individual radiosensitivity might be biased by the different subset frequencies if the dose-survival curves of the CD4 + and CD8 + cells differed. In the present study, CD4 + lymphocytes (helper/inducer T cells) and CD8 + lymphocytes (suppressor/cytotoxic T cells) were isolated from PBL and their dose-survival curves were determined. The results showed that the D 10 (the dose required to reduce the surviving fraction to 10 %) was quite similar for these two types of cells (3.13 ± 0.10 Gy [mean ±SD] for CD4 + , 3.34 ± 0.50 Gy for CD8 + and 3.07 ± 0.05 Gy for the unsorted cells), supporting the use of a whole PBL population for screening of individuals with altered radiosensitivity. (author)

  4. Kinetics of the formation of a G2 block from tritiated thymidine in phytohemagglutinin-stimulated human lymphocytes

    Pollack, A.; Bagwell, C.B.; Irvin, G.L.; Jensen, J.A.

    1980-01-01

    Flow cytometry (FCM) was used to monitor the radiation effects promoted by incorporated tritiated thymidine ( 3 H-TdR) on phytohemagglutinin (PHA)-stimulated human peripheral blood lymphocytes stained with propidium iodide (PI). Lymphocyte microcultures were continuously labeled or pulse-labeled for various periods of time with different 3 H-TdR concentrations. Two types of DNA histogram analyses were performed on unperturbed and 3 H]TdR perturbed lymphocytes. The data analyses consisted of statistical analyses between averaged groups of histograms (nonparametric analysis) and cell cycle analyses (parametric analysis) to determine the percentages of cells in G0 + G1, S and G2 + M. The results showed that (a) 3 H-TdR when added to proliferating lymphocytes under certain conditions (both short-term continuous and pulse-labeling) caused a highly significant increase in the proportion of tetraploid (4C) cells by FCM, (b) the increase in the proportion of 4C cells represented a block in G2 and (c) the relative increase in the percentage of 4C cells was proportional to 3 H-TdR incorporation which was proportional to labeling time and concentration. Therefore, it was concluded that short labeling times be used to minimize adverse radiation effects when 3 H-TdR is used to assay substances affecting lymphocyte proliferation or in the estimation of cell cycle time

  5. Molecular evidence of inefficient transduction of proliferating human B lymphocytes by VSV-pseudotyped HIV-1-derived lentivectors

    Serafini, M.; Naldini, L.; Introna, M.

    2004-01-01

    Lentiviral vectors are attractive tools to transduce dividing and nondividing cells. Human tonsillar B lymphocytes have been purified and induced to proliferate by the addition of anti-CD40 + IL-4 or anti-CD40 + anti-μ signals and transduced at high MOI with a VSV pseudotyped lentivector carrying the eGFP gene under the control of the PGK promoter. Parallel cultures of PHA-stimulated T lymphocytes containing a comparable amount of cycling cells during the infection reached over 70% eGFP transduction. By contrast, only less than 3% B lymphocytes became eGFP positive after 7 days from transduction. Molecular analysis of the viral life cycle shows that cytoplasmic retrotranscribed cDNA and nuclear 2LTR circles are detectable at lower levels and for a shorter period of time in proliferating B cells with respect to proliferating T lymphocytes. Moreover, FACS-sorted eGFP-positive and negative B cell populations were both positive for the presence of retrotranscribed cDNA and 2LTR circles nuclear forms. By contrast, nested Alu-LTR PCR allowed us to detect an integrated provirus in FACS-sorted eGFP-positive cells only. Together with the demonstration that infection in saturation conditions led to an increase in the percentage of transduced cells (reaching 9%), these findings suggest that in proliferating B lymphocytes, lentiviral transduction is an inefficient process blocked at the early steps of the viral life cycle possibly involving partially saturable restriction factors

  6. Human heavy-chain variable region gene family nonrandomly rearranged in familial chronic lymphocytic leukemia

    Shen, A.; Humphries, C.; Tucker, P.; Blattner, F.

    1987-01-01

    The authors have identified a family of human immunoglobulin heavy-chain variable-region (V/sub H/) genes, one member of which is rearranged in two affected members of a family in which the father and four of five siblings developed chronic lymphocytic leukemia. Cloning and sequencing of the rearranged V/sub H/ genes from leukemic lymphocytes of three affected siblings showed that two siblings had rearranged V/sub H/ genes (V/sub H/TS1 and V/sub H/WS1) that were 90% homologous. The corresponding germ-line gene, V/sub H/251, was found to part of a small (four gene) V/sub H/ gene family, which they term V/sub H/V. The DNA sequence homology to V/sub H/WS1 (95%) and V/sub H/TS1 (88%) and identical restriction sites on the 5' side of V/sub H/ confirm that rearrangement of V/sub H/251 followed by somatic mutation produced the identical V/sub H/ gene rearrangements in the two siblings. V/sub H/TS1 is not a functional V/sub H/ gene; a functional V/sub H/ rearrangement was found on the other chromosome of this patient. The other two siblings had different V/sub H/ gene rearrangements. All used different diversity genes. Mechanisms proposed for nonrandom selection of a single V/sub H/ gene include developmental regulation of this V/sub H/ gene rearrangement or selection of a subpopulation of B cells in which this V/sub H/ has been rearranged

  7. Potentiation of luteolin cytotoxicity by flavonols fisetin and quercetin in human chronic lymphocytic leukemia cell lines.

    Sak, Katrin; Kasemaa, Kristi; Everaus, Hele

    2016-09-14

    Despite numerous studies chronic lymphocytic leukemia (CLL) still remains an incurable disease. Therefore, all new compounds and novel strategies which are able to eradicate CLL cells should be considered as valuable clues for a potential future remedy against this malignancy. In the present study, the cytotoxic profiles of natural flavonoids were described in two human CLL cell lines, HG-3 and EHEB, indicating the flavone luteolin as the most potent flavonoid with half-maximal inhibitory constants (IC50) of 37 μM and 26 μM, respectively. Luteolin significantly increased the apoptotic cell population in both cell lines by increasing the activities of caspases-3 and -9 and triggering the intrinsic apoptotic pathway. Two flavonols, fisetin and quercetin, were somewhat less efficient in suppressing cellular viability, whereas baicalein, chrysin, (+)-catechin and hesperetin exerted only a small or no response at doses as high as 100 μM. Both fisetin and quercetin were able to augment the cytotoxic activity of luteolin in both cell lines by reducing the IC50 values up to four fold. As a result of this, luteolin displayed cytotoxicity activity already at low micromolar concentrations that could potentially be physiologically achievable through oral ingestion. No other tested flavonoids were capable of sensitizing CLL cells to luteolin pointing to a specific binding of fisetin and quercetin to the cellular targets which interfere with the signaling pathways induced by luteolin. Although further molecular studies to unravel this potentiating mechanism are certainly needed, this phenomenon could contribute to future remedies for prevention and treatment of chronic lymphocytic leukemia.

  8. Inhibition of human peripheral blood lymphocyte function by protoporphyrin and longwave ultraviolet light

    Barrett, K.E.; Yen, A.; Montisano, D.; Gigli, I.; Bigby, T.D.

    1994-01-01

    Modulation of immunologic effector cells by exogenous photoactive substances has been advanced as an underlying mechanism for the efficacy of various photochemotherapeutic regimens. It is also possible that endogenous photosensitizers, such as protoporphyrin, could similarly modify the function of immune cell types. The authors examined the effects of protoporphyrin plus longwave UV light on the ability of human PBL to proliferate in response to mitogens. Noncytotoxic dosages of protoporphyrin plus UV light suppressed PHA-stimulated proliferation of both PBMC and enriched T cells. CD8 + cells were more sensitive to this inhibitory effect than CD4 + cells. The inhibitory effect was also observed when proliferation was induced by the combination of a phorbol ester and ionomycin. Inhibition of PBMC proliferation was associated with inhibition of IL-2 secretion but proliferation was not restored with exogenous IL-2. Instead, the effect of protoporphyrin plus UV light may be on IL-2R. Cells treated with protoporphyrin and UV light did not display the increase in CD25 and β-chain of the IL-2R induced by PHA in control cells. In contrast to the effects of protoporphyrin and UV light on IL-2 and IL-2R α-chain protein expression, the accumulation of mRNA for these proteins induced by PHA was unaffected. None of the effects of protoporphyrin plus UV light on lymphocytes were observed in control experiments where cells were treated with either protoporphyrin or UV light alone. They conclude that biologically relevant dosages of protoporphyrin and UV light modify the function of circulating lymphocytes. 26 refs., 8 figs., 1 tab

  9. Dose-rate effects for apoptosis and micronucleus formation in gamma-irradiated human lymphocytes

    Boreham, D.R.; Dolling, J.-A.; Maves, S.R.; Siwarungsun, N.; Mitchel, R.E.J.

    2000-01-01

    We have compared dose-rate effects for γ-radiation-induced apoptosis and micronucleus formation in human lymphocytes. Long-term assessment of individual radiation-induced apoptosis showed little intraindividual variation but significant interindividual variation. The effectiveness of radiation exposure to cause apoptosis or micronucleus formation was reduced by low-dose-rate exposures, but the reduction was apparent at different dose rates for these two end points. Micronucleus formation showed a dose-rate effect when the dose rate was lowered to 0.29 cGy/min, but there was no accompanying cell cycle delay. A further increase in the dose-rate effect was seen at 0.15 cGy/min, but was now accompanied by cell cycle delay. There was no dose-rate effect for the induction of apoptosis until the dose rate was reduced to 0.15 cGy/min, indicating that the mechanisms or signals for processing radiation-induced lesions for these two end points must be different at least in part. There appear to be two mechanisms that contribute to the dose-rate effect for micronucleus formation. One of these does not affect binucleate cell frequency and occurs at dose rates higher than that required to produce a dose-rate effect for apoptosis, and one affects binucleate cell frequency, induced only at the very low dose rate which coincidentally produces a dose-rate effect for apoptosis. Since the dose rate at which cells showed reduced apoptosis as well as a further reduction in micronucleus formation was very low, we conclude that the processing of the radiation-induced lesions that induce apoptosis, and some micronuclei, is very slow in quiescent and PHA-stimulated lymphocytes, respectively. (author)

  10. Dose-rate effects for apoptosis and micronucleus formation in gamma-irradiated human lymphocytes

    Boreham, D.R.; Dolling, J.-A.; Maves, S.R. [Atomic Energy of Canada Limited, Chalk River, Ontario (Canada); Siwarungsun, N. [Chulalongkorn Univ., Bangkok (Thailand); Mitchel, R.E.J. [Atomic Energy of Canada Limited, Chalk River, Ontario (Canada)

    2000-07-01

    We have compared dose-rate effects for {gamma}-radiation-induced apoptosis and micronucleus formation in human lymphocytes. Long-term assessment of individual radiation-induced apoptosis showed little intraindividual variation but significant interindividual variation. The effectiveness of radiation exposure to cause apoptosis or micronucleus formation was reduced by low-dose-rate exposures, but the reduction was apparent at different dose rates for these two end points. Micronucleus formation showed a dose-rate effect when the dose rate was lowered to 0.29 cGy/min, but there was no accompanying cell cycle delay. A further increase in the dose-rate effect was seen at 0.15 cGy/min, but was now accompanied by cell cycle delay. There was no dose-rate effect for the induction of apoptosis until the dose rate was reduced to 0.15 cGy/min, indicating that the mechanisms or signals for processing radiation-induced lesions for these two end points must be different at least in part. There appear to be two mechanisms that contribute to the dose-rate effect for micronucleus formation. One of these does not affect binucleate cell frequency and occurs at dose rates higher than that required to produce a dose-rate effect for apoptosis, and one affects binucleate cell frequency, induced only at the very low dose rate which coincidentally produces a dose-rate effect for apoptosis. Since the dose rate at which cells showed reduced apoptosis as well as a further reduction in micronucleus formation was very low, we conclude that the processing of the radiation-induced lesions that induce apoptosis, and some micronuclei, is very slow in quiescent and PHA-stimulated lymphocytes, respectively. (author)

  11. Analysis of the frequency of unstable chromosome aberrations in human lymphocytes irradiated with 60Co

    Mendonca, Julyanne C.G.; Mendes, Mariana E.; Lima, Fabiana F.; Santos, Neide

    2013-01-01

    The aim of this study was to analyze the frequency of unstable chromosomal aberrations induced by gamma radiation from a 60 Co source at two different doses. Samples were obtained from a healthy donor and exposed to 60 Co source (Gammacel 220 ) located in the Department of Nuclear Energy of Pernambuco Federal University (DEN/UFPe/Brazil) with a rate of air Kerma to 3,277 Gy/h. Exposures resulted in absorbed dose 0.51 Gy and 0.77 Gy. Mitotic metaphases were obtained by culturing lymphocytes for chromosome analysis and the slides were stained with 5% Giemsa. Among the unstable chromosomal aberrations the dicentric chromosomes, ring chromosomes and acentric fragments were analyzed. To calculate the significance level the chi - square test was used, considering relevant differences between the frequencies when the value of p < 0.05. To calculate the significance level of the chi - square test was used, considering relevant differences between the frequencies when the value of p < 0.05. The results showed that there was significant difference of the frequencies of dicentric chromosomes (from 0.18 to 0.51 to 0.37 Gy to 0.77 Gy), however there was no statistically significant difference between the frequencies of acentric fragments ( 0.054 to 0, 51 Gy to 0.063 to 0.77 Gy) and ring chromosomes (0.001 to 0.51 Gy to 0.003 to 0.77 Gy). The low number of rings is found justified, considering that in irradiated human lymphocytes, its appearance is rare relative to dicentrics. The results confirm that dicentrics are the most reliable biomarkers in estimating dose after exposure to gamma radiation. These two points will make the calibration curve dose-response being built for Biological Dosimetry Laboratory of CRCN-NE/CNEN

  12. Synthesis and evaluation of the potential deleterious effects of ZnO nanomaterials (nanoneedles and nanoflowers) on blood components, including albumin, erythrocytes and human isolated primary neutrophils

    Pastrello, Bruna [São Paulo State University (UNESP), Department of Chemistry, Faculty of Sciences (Brazil); Paracatu, Luana Chiquetto [São Paulo State University (UNESP), Department of Clinical Analysis, School of Pharmaceutical Sciences (Brazil); Carvalho Bertozo, Luiza de [São Paulo State University (UNESP), Department of Chemistry, Faculty of Sciences (Brazil); Paino, Iêda Maria Martinez [University of São Paulo (USP), Nanomedicine and Nanotoxicology Group, Physics Institute of São Carlos (IFSC) (Brazil); Lisboa-Filho, Paulo Noronha [São Paulo State University (UNESP), Department of Physics, Faculty of Sciences (Brazil); Ximenes, Valdecir Farias, E-mail: vfximenes@fc.unesp.br [São Paulo State University (UNESP), Department of Chemistry, Faculty of Sciences (Brazil)

    2016-07-15

    The application of zinc oxide (ZnO) nanoparticles in biomaterials has increased significantly in the recent years. Here, we aimed to study the potential deleterious effects of ZnO on blood components, including human serum albumin (HSA), erythrocytes and human isolated primary neutrophils. To test the influence of the morphology of the nanomaterials, ZnO nanoneedles (ZnO-nn) and nanoflowers (ZnO-nf) were synthesized. The zeta potential and mean size of ZnO-nf and ZnO-nn suspensions in phosphate-buffered saline were −10.73 mV and 3.81 nm and −5.27 mV and 18.26 nm, respectively. The incubation of ZnO with HSA did not cause its denaturation as verified by the absence of significant alterations in the intrinsic and extrinsic fluorescence and in the circular dichroism spectrum of the protein. The capacity of HSA as a drug carrier was not affected as verified by employing site I and II fluorescent markers. Neither type of ZnO was able to provoke the activation of neutrophils, as verified by lucigenin- and luminol-dependent chemiluminescence and by the extracellular release of hydrogen peroxide. ZnO-nf, but not ZnO-nn, induced the haemolysis of erythrocytes. In conclusion, our results reinforce the concept that ZnO nanomaterials are relatively safe for usage in biomaterials. A potential exception is the capacity of ZnO-nf to promote the lysis of erythrocytes, a discovery that shows the importance of the morphology in the toxicity of nanoparticles.

  13. A simple in vitro method of radiolabelling human erythrocytes in whole blood with 113mIn-tropolonate

    Osman, S.; Danpure, H.J.

    1987-01-01

    A simple and rapid in vitro procedure has been developed for selectively radiolabelling erythrocytes in whole blood using 113m In-tropolonate. A maximum labelling efficiency of 97% was achieved, of which 95.5% was on the erythrocytes after only 5 min incubation of whole blodd at room temperature. The optimum amount of tropolone for labelling whole blood was 10 μg of tropolone per ml of blood using acid-citrate dextrose (ACD) as the anticoagulant and 50 μg of tropolone per ml of blood using heparin. Under these optimim conditions, only 2.5% of the cell-bound 113m In was released from the labelled cells during a 1 h in vitro incubation in cell-free plasma, irrespective of the anticoagulant used. These results suggest that 113m In-tropolonate may prove to be useful in vitro agent for labelling erythrocytes for short-term clinical investigations, especially at centres where 99m Tc and 111 In are unavailable. (author)

  14. A microculture system for generating haemolytic antibody responses from human tonsillar lymphocytes.

    Booth, R J

    1979-01-01

    Small numbers of Ficoll-Hypaque purified human tonsillar lymphocytes were stimulated with PWM to produce SRBC-specific PFC in a microculture system. The magnitude of the response varied among different tonsils but was typically between 200 and 1000 PFC/10(6) cells cultured. Little or no response was observed in the absence of PWM. SRBC failed to stimulate a SRBC-specific response and the presence of this antigen in PWM-stimulated cultures depressed the response. The time of the maximum response was inversely related to the number of cells cultured. In addition, the duration of the response was limited by rapid depletion of critical medium requirements and/or build up of inhibitory factors especially when the cell concentration exceeded 5 x 10(5) cells/culture. This effect could be partially overcome by daily feeding of cultures with fresh medium. Fractionation studies indicated a requirement for both T and B cell populations. Constant efficiency of PFC production with respect to cell number could be achieved by the addition of inactivated autologous 'filler' cells. The significance of these results and applicability of the microculture system to a detailed analysis of human antibody responses will be discussed.

  15. Protective Effect of Prolactin against Methylmercury-Induced Mutagenicity and Cytotoxicity on Human Lymphocytes

    Liz Carmem Silva-Pereira

    2014-09-01

    Full Text Available Mercury exhibits cytotoxic and mutagenic properties as a result of its effect on tubulin. This toxicity mechanism is related to the production of free radicals that can cause DNA damage. Methylmercury (MeHg is one of the most toxic of the mercury compounds. It accumulates in the aquatic food chain, eventually reaching the human diet. Several studies have demonstrated that prolactin (PRL may be differently affected by inorganic and organic mercury based on interference with various neurotransmitters involved in the regulation of PRL secretion. This study evaluated the cytoprotective effect of PRL on human lymphocytes exposed to MeHg in vitro, including observation of the kinetics of HL-60 cells (an acute myeloid leukemia lineage treated with MeHg and PRL at different concentrations, with both treatments with the individual compounds and combined treatments. All treatments with MeHg produced a significant increase in the frequency of chromatid gaps, however, no significant difference was observed in the chromosomal breaks with any treatment. A dose-dependent increase in the mitotic index was observed for treatments with PRL, which also acts as a co-mitogenic factor, regulating proliferation by modulating the expression of genes that are essential for cell cycle progression and cytoskeleton organization. These properties contribute to the protective action of PRL against the cytotoxic and mutagenic effects of MeHg.

  16. Protective Effect of Prolactin against Methylmercury-Induced Mutagenicity and Cytotoxicity on Human Lymphocytes

    Silva-Pereira, Liz Carmem; da Rocha, Carlos Alberto Machado; Cunha, Luiz Raimundo Campos da Silva e; da Costa, Edmar Tavares; Guimarães, Ana Paula Araújo; Pontes, Thais Brilhante; Diniz, Domingos Luiz Wanderley Picanço; Leal, Mariana Ferreira; Moreira-Nunes, Caroline Aquino; Burbano, Rommel Rodríguez

    2014-01-01

    Mercury exhibits cytotoxic and mutagenic properties as a result of its effect on tubulin. This toxicity mechanism is related to the production of free radicals that can cause DNA damage. Methylmercury (MeHg) is one of the most toxic of the mercury compounds. It accumulates in the aquatic food chain, eventually reaching the human diet. Several studies have demonstrated that prolactin (PRL) may be differently affected by inorganic and organic mercury based on interference with various neurotransmitters involved in the regulation of PRL secretion. This study evaluated the cytoprotective effect of PRL on human lymphocytes exposed to MeHg in vitro, including observation of the kinetics of HL-60 cells (an acute myeloid leukemia lineage) treated with MeHg and PRL at different concentrations, with both treatments with the individual compounds and combined treatments. All treatments with MeHg produced a significant increase in the frequency of chromatid gaps, however, no significant difference was observed in the chromosomal breaks with any treatment. A dose-dependent increase in the mitotic index was observed for treatments with PRL, which also acts as a co-mitogenic factor, regulating proliferation by modulating the expression of genes that are essential for cell cycle progression and cytoskeleton organization. These properties contribute to the protective action of PRL against the cytotoxic and mutagenic effects of MeHg. PMID:25247425

  17. Studies on the cytotoxicity of diamond nanoparticles against human cancer cells and lymphocytes.

    Adach, Kinga; Fijalkowski, Mateusz; Gajek, Gabriela; Skolimowski, Janusz; Kontek, Renata; Blaszczyk, Alina

    2016-07-25

    Detonation nanodiamonds (DND) are a widely studied group of carbon nanomaterials. They have the ability to adsorb a variety of biomolecules and drugs onto their surfaces, and additionally their surfaces may be subjected to chemical functionalization by covalent bonds. We present a procedure for the purification and surface oxidation of diamond nanoparticles, which were then tested by spectroscopic analysis such as ATR-FTIR, Raman spectroscopy, and thermogravimetric analysis. We also examined the zeta potential of the tested material. Analysis of the cytotoxic effect of nanodiamonds against normal lymphocytes derived from human peripheral blood, the non-small cell lung cancer cell line (A549) and the human colorectal adenocarcinoma cell line (HT29) was performed using MTT colorimetric assay. Evaluation of cell viability was performed after 1-h and 24-h treatment with the tested nanoparticles applied at concentrations ranging from 1 μg/ml to 100 μg/ml. We found that the survival of the examined cells was strongly associated with the presence of serum proteins in the growth medium. The incubation of cells with nanodiamonds in the presence of serum did not exert a significant effect on cell survival, while the cell treatment in a serum-free medium resulted in a decrease in cell survival compared to the negative control. The role of purification and functionalization of nanodiamonds on their cytotoxicity was also demonstrated. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  18. Chromosome painting analysis of X-ray-induced aberrations in human lymphocytes in vitro

    Matsuoka, A.; Hayashi, M.; Yamazaki, N.; Sofuni, T.

    1994-01-01

    Chromosomal rearrangements in human lymphocytes induced by X-rays (0, 0.5, 1.0 and 2.0 Gray) were analyzed using chromosome painting. DNA probes for human chromosomes 1, 3 or 4 alone, and a combination of 1 and 4, were used for analysis. The frequency of cells with rearrangements, i.e. reciprocal translocations, dicentrics, insertions, tricentrics and fragments, involving chromosome 4 increased with dose in both 48 and 72 h cultures. The number of translocations per cell also increased with dose at 48 and 72 h. Dicentrics increased with dose in 48 h but not in 72 h cultures. The estimated genomic frequency of aberrations per cell was comparable with results in banded cells. No difference was shown on the detection efficiency of chromosome rearrangements among the various DNA probes used. Since this technique does not necessarily require well-spread metaphases for analysis, it is possible to increase the number of analyzable metaphases compared with the banding technique. Chromosome painting is a simpler, more objective and practical method for detecting chromosome rearrangements than conventional banding analyses. (Author)

  19. Cross-reactivity of human nickel-reactive T-lymphocyte clones with copper and palladium

    Pistoor, F. H.; Kapsenberg, M. L.; Bos, J. D.; Meinardi, M. M.; von Blomberg, M. E.; Scheper, R. J.

    1995-01-01

    Twenty Ni-reactive T-lymphocyte clones were obtained from eight different donors and analyzed for their ability to cross-react with other metals. All Ni-reactive T-lymphocyte clones were CD4+CD8- and recognized Ni in association with either HLA-DR or -DQ molecules. Based on the periodic table of the

  20. Adaptive response in human blood lymphocytes exposed to non-ionizing radiofrequency fields: resistance to ionizing radiation-induced damage.

    Sannino, Anna; Zeni, Olga; Romeo, Stefania; Massa, Rita; Gialanella, Giancarlo; Grossi, Gianfranco; Manti, Lorenzo; Vijayalaxmi; Scarfì, Maria Rosaria

    2014-03-01

    The aim of this preliminary investigation was to assess whether human peripheral blood lymphocytes which have been pre-exposed to non-ionizing radiofrequency fields exhibit an adaptive response (AR) by resisting the induction of genetic damage from subsequent exposure to ionizing radiation. Peripheral blood lymphocytes from four healthy donors were stimulated with phytohemagglutinin for 24 h and then exposed for 20 h to 1950 MHz radiofrequency fields (RF, adaptive dose, AD) at an average specific absorption rate of 0.3 W/kg. At 48 h, the cells were subjected to a challenge dose (CD) of 1.0 or 1.5 Gy X-irradiation (XR, challenge dose, CD). After a 72 h total culture period, cells were collected to examine the incidence of micronuclei (MN). There was a significant decrease in the number of MN in lymphocytes exposed to RF + XR (AD + CD) as compared with those subjected to XR alone (CD). These observations thus suggested a RF-induced AR and induction of resistance to subsequent damage from XR. There was variability between the donors in RF-induced AR. The data reported in our earlier investigations also indicated a similar induction of AR in human blood lymphocytes that had been pre-exposed to RF (AD) and subsequently treated with a chemical mutagen, mitomycin C (CD). Since XR and mitomycin-C induce different kinds of lesions in cellular DNA, further studies are required to understand the mechanism(s) involved in the RF-induced adaptive response.

  1. Development of a serum-free medium for in vitro expansion of human cytotoxic T lymphocytes using a statistical design

    Lee Gyun

    2010-09-01

    Full Text Available Abstract Background Serum-containing medium (SCM, which has a number of poorly defined components with varying concentrations, hampers standardization of lymphocyte cultures. In order to develop a serum-free medium (SFM for the expansion of human lymphocytes from peripheral blood mononuclear cells (PBMCs, a statistical optimization approach based on a fractional factorial method and a response surface method was adopted. A basal medium was prepared by supplementing RPMI1640 medium with insulin, albumin, ferric citrate, ethanolamine, fatty acids, glutamine, sodium pyruvate, 2-mercaptoethanol, 1-thioglycerol, nonessential amino acids, and vitamins. We identified additional positive determinants and their optimal concentrations for cell growth through a statistical analysis. Results From a statistical analysis using the fractional factorial method, cholesterol and polyamine supplement were identified as positive determinants for cell growth. Their optimal concentrations were determined by the response surface method. The maximum viable cell concentration in the developed SFM was enhanced by more than 1.5-fold when compared to that in RPMI1640 supplemented with 10% fetal bovine serum (FBS. Furthermore, a cytotoxicity assay and an enzyme-linked immunospot assay revealed that the effector function of cytotoxic T lymphocytes generated from PBMCs grown in SFM, by stimulation of peptide-presenting dendritic cells, was retained or even better than that in SCM. Conclusions The use of a developed SFM with cholesterol and polyamine supplement for human lymphocyte culture resulted in better growth without loss of cellular function when compared to SCM.

  2. Development of a serum-free medium for in vitro expansion of human cytotoxic T lymphocytes using a statistical design.

    Jeon, Min Kyoung; Lim, Jong-Baeck; Lee, Gyun Min

    2010-09-21

    Serum-containing medium (SCM), which has a number of poorly defined components with varying concentrations, hampers standardization of lymphocyte cultures. In order to develop a serum-free medium (SFM) for the expansion of human lymphocytes from peripheral blood mononuclear cells (PBMCs), a statistical optimization approach based on a fractional factorial method and a response surface method was adopted. A basal medium was prepared by supplementing RPMI1640 medium with insulin, albumin, ferric citrate, ethanolamine, fatty acids, glutamine, sodium pyruvate, 2-mercaptoethanol, 1-thioglycerol, nonessential amino acids, and vitamins. We identified additional positive determinants and their optimal concentrations for cell growth through a statistical analysis. From a statistical analysis using the fractional factorial method, cholesterol and polyamine supplement were identified as positive determinants for cell growth. Their optimal concentrations were determined by the response surface method. The maximum viable cell concentration in the developed SFM was enhanced by more than 1.5-fold when compared to that in RPMI1640 supplemented with 10% fetal bovine serum (FBS). Furthermore, a cytotoxicity assay and an enzyme-linked immunospot assay revealed that the effector function of cytotoxic T lymphocytes generated from PBMCs grown in SFM, by stimulation of peptide-presenting dendritic cells, was retained or even better than that in SCM. The use of a developed SFM with cholesterol and polyamine supplement for human lymphocyte culture resulted in better growth without loss of cellular function when compared to SCM.

  3. Apoptosis induction in human lymphocytes after in vitro exposure to cobalt/hard metal compounds

    Boeck, M. de; Decordier, I.; Lombaert, N.; Cundari, E.; Kirsch-Volders, M.; Lison, D.

    2001-01-01

    Full text: An increased risk of lung cancer is associated with occupational exposure to mixtures of cobalt metal (Co) and tungsten carbide (WC) particles, but apparently not when exposure is to cobalt alone. The mechanism for this increased cancer risk is not fully understood. The evaluation of the in vitro genotoxic effects in lymphocytes exposed to varying cobalt species demonstrated that the WC-Co hard metal mixture is more genotoxic (DNA damage, chromosome/genome mutations) than metallic Co alone. WC alone was not genotoxic. Thus, WC-Co represents a specific (geno)toxic entity. In order to assess the survival of human lymphocytes after in vitro exposure to metallic Co, CoCl 2 , WC and the WC-Co mixture, two apoptosis/necrosis detection methods were applied (annexin V staining and flow cytometry). Annexin-V staining of early apoptotic cells demonstrated a dose- and time dependent induction of apoptosis by metallic Co, CoCl 2 , WC and the WC-Co mixture. The time course of the process varied according to the metal species tested. Metallic Co and CoCl 2 caused a gradually increasing frequency of apoptotic cells with time (up to 24 h). WC-induced apoptosis displayed a typical 6 hour peak, which was not the case for the WC-Co mixture or for Co. Apoptosis induction by the WC-Co mixture was intermediate between that induced by Co and WC separately. Analysis of propidium iodide stained cells by flow cytometry was performed as a later marker for apoptosis induction. Preliminary data indicate similar tendencies of apoptosis induction as those detected by annexin-V. Identification of the apoptotic pathway triggered by the metal compounds was studied by inhibition of the ceramide-apoptosis pathway by fumonisin causing reduction of apoptosis induction for all compounds, but strongest after 6 hour exposure to WC. The use of specific caspase inhibitors will allow to further elucidate the different pathways involved. The current data demonstrating in vitro the apoptosis

  4. Apoptosis induction in human lymphocytes after in vitro exposure to cobalt/hard metal compounds

    Boeck, M de; Decordier, I; Lombaert, N; Cundari, E; Kirsch-Volders, M [Vrije Universiteit Brussel, Laboratorium voor Cellulaire Genetica, Brussel (Belgium); Lison, D [Universite catholique de Louvain, Unite de Toxicologie industrielle et Medecine du Travail, Bruxelles (Belgium)

    2001-07-01

    Full text: An increased risk of lung cancer is associated with occupational exposure to mixtures of cobalt metal (Co) and tungsten carbide (WC) particles, but apparently not when exposure is to cobalt alone. The mechanism for this increased cancer risk is not fully understood. The evaluation of the in vitro genotoxic effects in lymphocytes exposed to varying cobalt species demonstrated that the WC-Co hard metal mixture is more genotoxic (DNA damage, chromosome/genome mutations) than metallic Co alone. WC alone was not genotoxic. Thus, WC-Co represents a specific (geno)toxic entity. In order to assess the survival of human lymphocytes after in vitro exposure to metallic Co, CoCl{sub 2}, WC and the WC-Co mixture, two apoptosis/necrosis detection methods were applied (annexin V staining and flow cytometry). Annexin-V staining of early apoptotic cells demonstrated a dose- and time dependent induction of apoptosis by metallic Co, CoCl{sub 2}, WC and the WC-Co mixture. The time course of the process varied according to the metal species tested. Metallic Co and CoCl{sub 2} caused a gradually increasing frequency of apoptotic cells with time (up to 24 h). WC-induced apoptosis displayed a typical 6 hour peak, which was not the case for the WC-Co mixture or for Co. Apoptosis induction by the WC-Co mixture was intermediate between that induced by Co and WC separately. Analysis of propidium iodide stained cells by flow cytometry was performed as a later marker for apoptosis induction. Preliminary data indicate similar tendencies of apoptosis induction as those detected by annexin-V. Identification of the apoptotic pathway triggered by the metal compounds was studied by inhibition of the ceramide-apoptosis pathway by fumonisin causing reduction of apoptosis induction for all compounds, but strongest after 6 hour exposure to WC. The use of specific caspase inhibitors will allow to further elucidate the different pathways involved. The current data demonstrating in vitro the

  5. The approximate entropy of the electromyographic signals of tremor correlates with the osmotic fragility of human erythrocytes

    Penha-Silva Nilson

    2010-06-01

    Full Text Available Abstract Background The main problem of tremor is the damage caused to the quality of the life of patients, especially those at more advanced ages. There is not a consensus yet about the origins of this disorder, but it can be examined in the correlations between the biological signs of aging and the tremor characteristics. Methods This work sought correlations between the osmotic fragility of erythrocytes and features extracted from electromyographic (EMG activity resulting from physiological tremor in healthy patients (N = 44 at different ages (24-87 years. The osmotic fragility was spectrophotometrically evaluated by the dependence of hemolysis, provided by the absorbance in 540 nm (A54o, on the concentration of NaCl. The data were adjusted to curves of sigmoidal regression and characterized by the half transition point (H50, amplitude of lysis transition (dx and values of A540 in the curve regions that characterize the presence of lysed (A1 and preserved erythrocytes (A2. The approximate entropy was estimated from EMG signals detected from the extensor carpi ulnaris muscle during the movement of the hand of subjects holding up a laser pen towards an Archimedes spiral, fixed in a whiteboard. The evaluations were carried out with the laser pen at rest, at the center of the spiral, and in movement from the center to the outside and from outside to the center. The correlations among the parameters of osmotic fragility, tremor and age were tested. Results Negative correlations with age were found for A1 and dx. With the hand at rest, a positive correlation with H50 was found for the approximate entropy. Negative correlations with H50 were found for the entropy with the hand in movement, as from the center to the outside or from the outside to the center of the spiral. Conclusion In healthy individuals, the increase in the erythrocyte osmotic fragility was associated with a decrease in the approximate entropy for rest tremor and with an increase

  6. Genomic instability after targeted irradiation of human lymphocytes: Evidence for inter-individual differences under bystander conditions

    Kadhim, Munira A.; Lee, Ryonfa; Moore, Stephen R.; Macdonald, Denise A.; Chapman, Kim L.; Patel, Gaurang; Prise, Kevin M.

    2010-01-01

    Environmental 222 radon exposure is a human health concern, and many studies demonstrate that very low doses of high LET α-particle irradiation initiate deleterious genetic consequences in both irradiated and non-irradiated bystander cells. One consequence, radiation-induced genomic instability (RIGI), is a hallmark of tumorigenesis and is often assessed by measuring delayed chromosomal aberrations. We utilised a technique that facilitates transient immobilization of primary lymphocytes for targeted microbeam irradiation and have reported that environmentally relevant doses, e.g. a single 3 He 2+ particle traversal to a single cell, are sufficient to induce RIGI. Herein we sought to determine differences in radiation response in lymphocytes isolated from five healthy male donors. Primary lymphocytes were irradiated with a single particle per cell nucleus. We found evidence for inter-individual variation in radiation response (RIGI, measured as delayed chromosome aberrations). Although this was not highly significant, it was possibly masked by high levels of intra-individual variation. While there are many studies showing a link between genetic predisposition and RIGI, there are few studies linking genetic background with bystander effects in normal human lymphocytes. In an attempt to investigate inter-individual variation in the induction of bystander effects, primary lymphocytes were irradiated with a single particle under conditions where fractions of the population were traversed. We showed a marked genotype-dependent bystander response in one donor after exposure to 15% of the population. The findings may also be regarded as a radiation-induced genotype-dependent bystander effect triggering an instability phenotype.

  7. Genomic instability after targeted irradiation of human lymphocytes: Evidence for inter-individual differences under bystander conditions

    Kadhim, Munira A., E-mail: mkadhim@brookes.ac.uk [School of Life Sciences, Oxford Brookes University, Oxford OX3 0BP (United Kingdom); Lee, Ryonfa [Biophysics, GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, Planckstrasse 1, D-64291 Darmstadt (Germany); Moore, Stephen R.; Macdonald, Denise A. [Radiation and Genome Stability Unit, Medical Research Council, Harwell, Oxfordshire OX11 0RD (United Kingdom); Chapman, Kim L. [School of Life Sciences, Oxford Brookes University, Oxford OX3 0BP (United Kingdom); Patel, Gaurang; Prise, Kevin M. [Centre for Cancer Research and Cell Biology, Queen' s University Belfast, Belfast BT9 7BL (United Kingdom)

    2010-06-01

    Environmental {sup 222}radon exposure is a human health concern, and many studies demonstrate that very low doses of high LET {alpha}-particle irradiation initiate deleterious genetic consequences in both irradiated and non-irradiated bystander cells. One consequence, radiation-induced genomic instability (RIGI), is a hallmark of tumorigenesis and is often assessed by measuring delayed chromosomal aberrations. We utilised a technique that facilitates transient immobilization of primary lymphocytes for targeted microbeam irradiation and have reported that environmentally relevant doses, e.g. a single {sup 3}He{sup 2+} particle traversal to a single cell, are sufficient to induce RIGI. Herein we sought to determine differences in radiation response in lymphocytes isolated from five healthy male donors. Primary lymphocytes were irradiated with a single particle per cell nucleus. We found evidence for inter-individual variation in radiation response (RIGI, measured as delayed chromosome aberrations). Although this was not highly significant, it was possibly masked by high levels of intra-individual variation. While there are many studies showing a link between genetic predisposition and RIGI, there are few studies linking genetic background with bystander effects in normal human lymphocytes. In an attempt to investigate inter-individual variation in the induction of bystander effects, primary lymphocytes were irradiated with a single particle under conditions where fractions of the population were traversed. We showed a marked genotype-dependent bystander response in one donor after exposure to 15% of the population. The findings may also be regarded as a radiation-induced genotype-dependent bystander effect triggering an instability phenotype.

  8. Radiosensitivity of different aged human lymphocytes following electron irradiation in vitro

    Joksic, G.; Nikolic, M.; Spasojevic-Tisma, V.

    1997-01-01

    Cytochalasin B-blocking micronucleus test and chromosomal aberration analysis were used in this study to estimate the yield of individual variability in radiation response of different aged human lymphocytes. Both analyses were performed in three groups of adults, aged 18-65 years, on two sampling times, following irradiation by therapeutical dose of 2 G in vitro. No statistically significant difference in the induced yield of exchange aberrations between individuals under consideration was found. The yield of total aberration data showed greater variability and was statistically significant in the oldest group against two other adult groups. Regarding to fixation times no statistically significant differences in the induced yield of chromosomal aberration (exchanges as well as total aberrations) were observed. The study has shown a slight increase in spontaneously occurring micronuclei with age. Almost equal mean number of radiation induced micronuclei was observed in the groups of adult aged 18-20 and 45-55 years. The highest mean number was observed in the oldest group. Evident variation in number of radiation induced micronuclei among individuals from the same age group was observed. The results of micronuclei assay for for all individuals under consideration show statistically significant difference in the yield of radiation-induced micronuclei regarding the second fixation time. This study has shown that cytochalasin-B blocking micronucleus test is more sensitive assay than chromosomal aberration analysis for the estimation of individual radiosensitivity. (author)

  9. Induction of complete and incomplete chromosome aberrations by bleomycin in human lymphocytes

    Benkhaled, L.; Xuncla, M.; Caballin, M.R.; Barrios, L.; Barquinero, J.F.

    2008-01-01

    Bleomycin (BLM) is a clastogenic compound, which due to the overdispersion in the cell distribution of induced dicentrics has been compared to the effect of high-LET radiation. Recently, it has been described that in fibroblast derived cell lines BLM induces incomplete chromosome elements more efficiently than any type of ionizing radiation. The objective of the present study was to evaluate in human lymphocytes the induction of dicentrics and incomplete chromosome elements by BLM. Peripheral blood samples have been treated with different concentrations of BLM. Two cytogenetic techniques were applied, fluorescence plus Giemsa (FPG) and FISH using pan-centromeric and pan-telomeric probes. The observed frequency of dicentric equivalents increases linearly with the BLM concentration, and for all BLM concentrations the distribution of dicentric equivalents was overdispersed. In the FISH study the ratio between total incomplete elements and multicentrics was 0.27. The overdispersion in the dicentric cell distribution, and the linear BLM-concentration dependence of dicentrics can be compared to the effect of high-LET radiation, on the contrary the ratio of incomplete elements and multicentrics is similar to the one induced by low-LET radiation (∼0.40). The elevated proportion of interstitial deletions in relation to total acentric fragments, higher than any type of ionizing radiation could be a characteristic signature of the clastogenic effect of BLM

  10. RBE of thermal neutrons for induction of chromosome aberrations in human lymphocytes.

    Schmid, E; Wagner, F M; Canella, L; Romm, H; Schmid, T E

    2013-03-01

    The induction of chromosome aberrations in human lymphocytes irradiated in vitro with slow neutrons was examined to assess the maximum low-dose RBE (RBE(M)) relative to (60)Co γ-rays. For the blood irradiations, cold neutron beam available at the prompt gamma activation analysis facility at the Munich research reactor FRM II was used. The given flux of cold neutrons can be converted into a thermally equivalent one. Since blood was taken from the same donor whose blood had been used for previous irradiation experiments using widely varying neutron energies, the greatest possible accuracy was available for such an estimation of the RBE(M) avoiding the inter-individual variations or differences in methodology usually associated with inter-laboratory comparisons. The magnitude of the coefficient α of the linear dose-response relationship (α = 0.400 ± 0.018 Gy(-1)) and the derived RBE(M) of 36.4 ± 13.3 obtained for the production of dicentrics by thermal neutrons confirm our earlier observations of a strong decrease in α and RBE(M) with decreasing neutron energy lower than 0.385 MeV (RBE(M) = 94.4 ± 38.9). The magnitude of the presently estimated RBE(M) of thermal neutrons is-with some restrictions-not significantly different to previously reported RBE(M) values of two laboratories.

  11. Micronuclei induced by fast neutrons versus 60Co gamma-rays in human peripheral blood lymphocytes.

    Vral, A; Verhaegen, F; Thierens, H; De Ridder, L

    1994-03-01

    Here we compared the effectiveness of neutrons ( = 5.5 MeV) versus 60Co gamma-rays in producing micronuclei (MN) in human lymphocytes. To obtain dose-response data, blood samples of six donors were irradiated with doses ranging from 0.1 to 5 Gy for gamma-rays and 0.1-3 Gy for neutrons. A linear dependence of MN yield with dose was found for fast neutrons while for gamma-rays a nonlinear dependence existed. For both radiation qualities no significant interindividual differences were found. Derived relative biological effectiveness values decreased with increasing dose. The MN frequency distributions were overdispersed with respect to the Poisson distribution, with neutrons showing higher dispersion values than with gamma-rays. To compare the repair kinetics of both radiation qualities split-dose experiments were performed. A dose of 4 Gy gamma-rays (3 Gy neutrons) was delivered either as a single exposure or in two equal fractions separated by time intervals ranging from 30 min to 10 h (30 min to 7 h for neutrons). The data showed for gamma-rays a significant decline (30% +/- 10%) in MN yield with interfraction time due to repair of DNA damage. This repair is a continuous process starting almost immediately after the first of the two doses and lasting 3-5 h. For fast neutrons no decline was observed indicating irreparable damage.

  12. Adaptive response induced by low doses of ionizing radiation in human lymphocytes

    Frati, Diego Libkind; Bunge, Maria M.

    2001-01-01

    The term adaptive response (AR) applies to the phenomenon of protection or enhanced repair induced by a small dose of a mutagenic agent. In order to determine the existence of AR in human lymphocytes for two different irradiation schemes, microcultures of blood from 4 donors were irradiated. Samples were exposed 24 hours (hr) after phytohemagglutinin stimulation to an adapting dose of 0,01 Gy and to a challenging dose of 1,5 Gy either 6 or 24 hr later (irradiation scheme 24+30 or 24+48, respectively). Gamma radiation from a 2,5 MeV Linac was used in all experiments. A cytogenetic analysis of unstable chromosome aberrations was applied as the endpoint. High inter-individual variability was found for the first irradiation scheme: one expressed AR, two did not and the last showed an apparent synergistic response. For the second irradiation scheme, low mitotic indices (MI) were found, suggesting a G2 arrest. When a series of harvesting times were applied for the last donor, normal MI were obtained only harvesting after 58 hr. An AR was found when harvesting at 72 hr but not at 58 hr. (author)

  13. Chromosome aberrations in human lymphocytes after irradiation with NIRS-cyclotron fast neutrons in vitro

    Muramatsu, Susumu; Maruyama, Takashi

    1977-01-01

    The dose-response relationships for inducing chromosome aberrations (dicentrics) in human lymphocytes were studied by whole-blood microculture following in vitro exposures at various doses either 200 kVp x-rays or NIRS-cyclotron fast neutrons. The yields of dicentrics induced were dependent on the exposure dose of two types of radiations between 48 to 384 rad and 25 to 400 rad by x-rays and fast neutrons, respectively. The dicentrics yields gave the best fit to the linear quadratic function Y=αD + βD 2 ; namely Y sub(X)=3.66 x 10 -4 D + 8.01 x 10 -6 D 2 for x-rays and Y sub(N)=28.90 x 10 -4 D + 4.04 x 10 -6 D 2 for fast neutrons. The RBE value of NIRS-cyclotron fast neutrons versus 200 kVP x-rays decreased with increasing neutron doses, for example from 2.3 at 50 rad to 1.2 at doses up to 300 rad. (auth.)

  14. Establishment and characterization of Epstein-Barr virus-specific human CD4+ T lymphocyte clones

    Honda, S.; Okuno, K.; Yasutomi, M.; Takasaki, T.; Kurane, I.

    1998-01-01

    We developed a simple method for establishing Epstein-Barr virus (EBV)-specific, human CD4+ T cell clones. The method originates from our experience that the regression of cell growth in in vitro EBV transformation of B cells occurs when round lymphoid cells appear in the culture. Peripheral blood mononuclear cells were cultured with EBV; and IL-2 (20 U/ml) was added to the culture on day 17 after the virus addition. The phenotype of the growing cells was CD3+ , CD4+ , and CD8-. The cells were cytotoxic for autologous lymphoblastoid B cell line (LCL) and EBV-super-infected autologous LCL. The cytotoxic T lymphocytes (CTLs) were confirmed to be CD4+ T cells but not CD8+ T cells in the culture. CTL clones were established by a limiting dilution method. All the CTL clones had the phenotype of CD3+ , CD4+ and CD8-, and proliferated in response to autologous LCL. They produced interferon (IFN)-gamma, interleukin 2 (IL-2) and tumour necrosis factor (TNF)-beta but not IL-4. All but one clone responded to both autologous, EBV-super-infected and non-super-infected LCLs. Proliferative and cytotoxic responses to allogeneic LCLs were heterogeneous. These results suggest that this method induces heterogeneous, EBV-specific CD4+ CTL clones and is useful for analysis of CD4+ T cells in EBV infections. (authors)

  15. Effect of tritiated compounds on sister-chromatid exchanges (SCE) in human lymphocytes in vitro

    Gong Manli; Rao Yongqing; Chen Guanying; Wu Weiwei; Zhao Zilan; Shen Lei

    1990-01-01

    Human lymphocytes treated in vitro with various activities of 3 H-TdR and 3 H-UdR were cultured to understand the effects of tritium on the cell cycle and the frequency of SCE. The results of these experiments indicated that both tritiated compounds make the frequency of SCE increase and the cell cycle delay. The frequency of SCE increased markedly with activity of 3 H. With respect to delaying cell cycle, 3 H-UdR was more effective than 3 H-TdR. The average frequencies of SCE for 3 H-UdR were higher than those for 3 H-TdR. With the exception of 3.7 x 10 3 Bq/mL group and differences between other 3 H-UdR groups and corresponding 3 H-TdR group were significant (t test, p < 0.01). These results suggest that tritiated compounds may have the effect on the cell proliferating rate. The cell proliferating rate index (PRI) seems to be related with the frequency of SCE: the higher the frequency of SCE, the lower the PRI is

  16. Effects on DNA repair in human lymphocytes exposed to the food dye tartrazine yellow.

    Soares, Bruno Moreira; Araújo, Taíssa Maíra Thomaz; Ramos, Jorge Amando Batista; Pinto, Laine Celestino; Khayat, Bruna Meireles; De Oliveira Bahia, Marcelo; Montenegro, Raquel Carvalho; Burbano, Rommel Mario Rodríguez; Khayat, André Salim

    2015-03-01

    Tartrazine is a food additive that belongs to a class of artificial dyes and contains an azo group. Studies about its genotoxic, cytotoxic and mutagenic effects are controversial and, in some cases, unsatisfactory. This work evaluated the potential in vitro cytotoxicity, genotoxicity and effects on DNA repair of human lymphocytes exposed to the dye. We assessed the cytotoxicity of tartrazine by 3-(4,5-Dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide test and the response of DNA repair through comet assay (alkaline version). We used different concentrations of the dye, ranging from 0.25-64.0 mM. The results demonstrated that tartrazine has no cytotoxic effects. However, this dye had a significant genotoxic effect at all concentrations tested. Although most of the damage was amenable to repair, some damage remained higher than positive control after 24 h of repair. These data demonstrate that tartrazine may be harmful to health and its prolonged use could trigger carcinogenesis. Copyright© 2015 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

  17. Induction of aberrations in human lymphocytes by γ-rays and fast heavy ions

    Govorun, R.D.; Repin, M.V.; Krasavin, E.A.; Lukasova, E.; Kozubek, S.; Kroha, V.

    1998-01-01

    Frequencies of aberrations induced by different doses of γ-rays and 14 N ions (LET ∼ 77 keV/μm) in the chromosomes 1 and 2 of human lymphocytes as detected by FISH were compared with those detected by conventional staining in the whole genome. The results have shown that the induction of aberrations in the chromosomes 1 and 2 is more frequent than that in the rest of genome. The frequencies of dicentrics detected by FISH in the chromosomes 1 and 2 recalculated for the whole genome are in good agreement with those detected by conventional staining at different doses of 14 N, but they are about 2 times lower at low doses of γ-rays. Translocation frequencies calculated in the same manner from the frequencies induced in the chromosome 1 by γ-rays correspond to the frequencies of dicentrics detected by conventional staining, however, they are about 2 times higher than those detected by convectional staining at doses lower than 2 Gy of 14 N. The differences between the frequencies of these aberration types increase at higher doses of both radiation types

  18. PKCθ is required for the activation of human T lymphocytes induced by CD43 engagement

    Rio, Roxana del; Rincon, Mercedes; Layseca-Espinosa, Esther; Fierro, Nora A.; Rosenstein, Yvonne; Pedraza-Alva, Gustavo

    2004-01-01

    The turnover of phosphoinositides leading to PKC activation constitutes one of the principal axes of intracellular signaling. In T lymphocytes, the enhanced and prolonged PKC activation resulting from the engagement of the TcR and co-receptor molecules ensures a productive T cell response. The CD43 co-receptor promotes activation and proliferation, by inducing IL-2 secretion and CD69 expression. CD43 engagement has been shown to promote phosphoinositide turnover and DAG production. Moreover, PKC activation was found to be required for the activation of the MAP kinase pathway in response to CD43 ligation. Here we show that CD43 engagement led to the membrane translocation and enzymatic activity of specific PKC isoenzymes: cPKC (α/β), nPKC (ε and θ), aPKC (ζ) and PKCμ. We also show that activation of PKCθ resulting from CD43 ligation induced CD69 expression through an ERK-dependent pathway leading to AP-1, NF-κB activation and an ERK independent pathway promoting NFAT activation. Together, these data suggest that PKCθ plays a critical role in the co-stimulatory functions of CD43 in human T cells

  19. Chromosome aberrations in human peripheral lymphocytes induced by single or fractionated X-irradiation

    Ivanov, B.; Leonard, A.; Deknyudt, G.

    1980-01-01

    Investigated is the effect of single (125 and 250 R) and fractionated (2x125 R) irradiation on the output of chromosome aberrations in lymphocytes of human peripheral blood kept between irradiations at the temperature of 5 deg C. The single irradiation is carried out immediately after vein-puncture. In the case of fractionated irradiation the first dose of 125R is given after vein-puncture, the second, in the interval of 2, 8 and 24 hours. Blood is cultivated immediately after two irradiations in order to prepare metaphase plates for cytogenic analysis. Repair processes in cell heritage structures are not realised in blood irradiated by fractions which is kept at 5 deg C between irradiations. On the contrary, chromosome fragments, interstitial deletions, aberrant cells and cell breaks are found in a large amount in blood irradiated by fractions. They have appeared with the authentically high statistic difference as compared with the cells irradiated one time with the same dose. This effect is probably attained due to blood preservation

  20. Ex vivo measurement of calpain activation in human peripheral blood lymphocytes by detection of immunoreactive products of calpastatin degradation.

    Jacek M Witkowski

    2008-01-01

    Full Text Available Limited proteolysis of multiple intracellular proteins by endogenous Ca-dependent cysteine proteases--calpains--is an important regulatory mechanism for cell proliferation, apoptosis etc. Its importance for cellular functions is stressed by existence of endogenous calpain inhibitors--calpastatins. The calpain-calpastatin system within living cells is in a fragile balance, which depends on both partners. The interdependence of calpain--a protease--and calpastatin--an endogenous inhibitor and at the same time a substrate for this enzyme makes any assessment of actual activity of this enzyme in the cells very difficult. In this work we made an attempt to estimate and compare the activity of calpain in human peripheral blood lymphocytes by assessing the levels of limited proteolysis of calpastatin in these cells by western blot, while at the same time the levels of calpain protein inside these cells was measured by flow cytometry. Our results indicate that it is possible to compare (semi-quantitatively the activities of calpain in peripheral blood CD4+ and CD19+ lymphocytes from various donors that way. Preliminary results showed that calpain activity is increased in the CD4+ T cells isolated from peripheral blood of rheumatoid arthritis patients as compared to control lymphocytes. Extremely high intrinsic activity of calpain was detected in chronic lymphocytic leukemia (CD19+ cells. All this confirms the detection of immunoreactive products of calpastatin as a good maker of endogenous calpain activity.

  1. Clastogenic effects in human lymphocytes exposed to low and high dose rate X-ray irradiation and vitamin C

    Konopacka, M; Rogolinski, J.

    2011-01-01

    In the present work we investigated the ability of vitamin C to modulate clastogenic effects induced in cultured human lymphocytes by X-irradiation delivered at either high (1 Gy/min) or low dose rate (0.24 Gy/min). Biological effects of the irradiation were estimated by cytokinesis-block micronucleus assay including the analysis of the frequency of micronuclei (MN) and apoptotic cells as well as calculation of nuclear division index (NDI). The numbers of micronucleated binucleate lymphocytes (MN-CBL) were 24.85 ± 2.67% and 32.56 ± 3.17% in cultures exposed to X-rays (2 Gy) delivered at low and high dose rates, respectively. Addition of vitamin C (1-20 μg/ml) to the medium of cultures irradiated with the low dose rate reduced the frequency of micronucleated lymphocytes with multiple MN in a concentration-dependent manner. Lymphocytes exposed to the high dose rate radiation showed a U-shape response: low concentration of vitamin C significantly reduced the number of MN, whereas high concentration influenced the radiation-induced total number of micronucleated cells insignificantly, although it increased the number of cells with multiple MN. Addition of vitamin C significantly reduced the fraction of apoptotic cells, irrespective of the X-ray dose rate. These results indicate that radiation dose rate is an important exposure factor, not only in terms of biological cell response to irradiation, but also with respect to the modulating effects of antioxidants. (authors)

  2. Effects of synthetic and naturally occurring flavonoids on mitogen-induced proliferation of human peripheral-blood lymphocytes

    Hirano, Toshihiko; Oka, Kitaro; Kawashima, Etsuko; Akiba, Mitsuo

    1989-01-01

    Examination was made of the effects of 17 synthetic and naturally occurring flavonoids on human lymphocyte proliferation in the presence of concanavalin A as a mitogen. Twelve of the flavonoids examined were mono-hydroxy of methoxy derivatives. The mitogen-induced response of lymphocytes was evaluated from the extent of the incorporation of [ 3 H]thymidine into cells in vitro. All the compounds showed inhibitory effects; 4.5-77.7% of [ 3 H] thymidine incorporation was blocked by an 1.0 μg/ml concentration. The viability of lymphocytes before and after treatment, as assessed by a dye exclusion test, indicated no change, and thus the flavonoids may inhibit DNA synthesis. The flavonoids possessing 5-hydroxyl, 5-methoxyl and 6-methoxyl groups, and those with cyclohexyl instead of phenyl substituent (i.e. 2-cyclohexyl-benzopyran-4-one), showed the greatest inhibition. The inhibitory effect of any one of them was less than one half that of prednisolone, but essentially the same or somewhat exceeding that of bredinine of azathioprine. It would thus appear that the well-known anti-inflammatory effects of flavonoids may possibly arise in part from the inhibition of the proliferative response of lymphocytes

  3. Tumor necrosis factor-α inhibits effects of aryl hydrocarbon receptor ligands on cell death in human lymphocytes.

    Ghatrehsamani, Mahdi; Soleimani, Masoud; Esfahani, Behjat A Moayedi; Shirzad, Hedayatollah; Hakemi, Mazdak G; Mossahebimohammadi, Majid; Eskandari, Nahid; Adib, Minoo

    2015-01-01

    Activation of aryl hydrocarbon receptor (AhR) leads to diverse outcome in various kinds of cells. AhR activation may induce apoptosis or prevent of apoptosis and cell death. Recent studies suggest that apoptosis effects of AhR can be modulated by inflammatory cytokine like tumor necrosis factor alpha (TNF-α). In this study, we try to investigate the possible interaction of TNF-α with the 2, 3, 7, 8-tetrachlorodibenzo-p-dioxin (TCDD), a ligand of AhR, on peripheral lymphocytes. Human peripheral blood mononuclear cells (PBMCs) were isolated from peripheral blood by discontinuous density gradient centrifugation on ficoll. Isolated PBMCs were divided into four groups: Control group, TNF-α administered group, TCDD administered group, co-administered group with TCDD and TNF-α. Cells were maintained for a week in lymphocyte culture condition. Then, TNF-α was added to group 2 and 4. Finally, apoptosis and necrosis were analyzed in all samples using flowcytometry. In group 4, the mean percent of necrosis and apoptosis in TCDD treatment groups was significantly larger than other groups; (P 0.05). However, the mean percent of cell death in co-administered group with TCDD and TNF-α was significantly lower than other groups; (P < 0.05). TNF-α could significantly inhibit effects of TCDD on lymphocytes apoptosis. Combination effects of TNF-α and TCDD on lymphocyte increase cell survival.

  4. Uptake of Eudragit Retard L (Eudragit® RL Nanoparticles by Human THP-1 Cell Line and Its Effects on Hematology and Erythrocyte Damage in Rats

    Mosaad A. Abdel-Wahhab

    2014-02-01

    Full Text Available The aim of this study was to prepare Eudragit Retard L (Eudragit RL nanoparticles (ENPs and to determine their properties, their uptake by the human THP-1 cell line in vitro and their effect on the hematological parameters and erythrocyte damage in rats. ENPs showed an average size of 329.0 ± 18.5 nm, a positive zeta potential value of +57.5 ± 5.47 mV and nearly spherical shape with a smooth surface. THP-1 cell lines could phagocyte ENPs after 2 h of incubation. In the in vivo study, male Sprague-Dawley rats were exposed orally or intraperitoneally (IP with a single dose of ENP (50 mg/kg body weight. Blood samples were collected after 4 h, 48 h, one week and three weeks for hematological and erythrocytes analysis. ENPs induced significant hematological disturbances in platelets, red blood cell (RBC total and differential counts of white blood cells (WBCs after 4 h, 48 h and one week. ENP increased met-Hb and Co-Hb derivatives and decreased met-Hb reductase activity. These parameters were comparable to the control after three weeks when administrated orally. It could be concluded that the route of administration has a major effect on the induction of hematological disturbances and should be considered when ENPs are applied for drug delivery systems.

  5. Enrichment of antioxidants in black garlic juice using macroporous resins and their protective effects on oxidation-damaged human erythrocytes.

    Zou, Ying; Zhao, Mouming; Yang, Kun; Lin, Lianzhu; Wang, Yong

    2017-08-15

    The black garlic juice is popular for its nutritive value. Enrichment of antioxidants is needed to make black garlic extract an effective functional ingredient. Five macroporous resins were evaluated for their capacity in adsorbing antioxidants in black garlic juice. XAD-16 resin was chosen for further study due to its high adsorption and desorption ratios. Pseudo-second-order kinetics (q e =625μmol Trolox equiv/g dry resin, k 2 =0.0001463) and Freundlich isotherm models (ΔH=-10.1547kJ/mol) were suitable for describing the whole exothermic and physical adsorption processes of the antioxidants from black garlic juice on XAD-16 resin. The antioxidants and phenolics were mostly enriched in 40% ethanol fraction by XAD-16 resin column chromatography. The black garlic extract and its fractions could protect erythrocytes against AAPH-induced hemolysis in dose-dependent manners. The pretreatment of AAPH-damaged erythrocytes with 40% ethanol fractions (2.5mg/mL) significantly decreased the hemolysis ratios from 53.58% to 3.79%. The 40% ethanol fraction possessing strong intracellular antioxidant activity could be used as a functional food ingredient. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Comment of the paper 'Chromosome aberrations induced by low doses of X-rays in human lymphocytes in vitro'

    Merkle, W.; Paretzke, H.G.

    1981-01-01

    This comment points out some problems in the statistical evaluation of the data of Ziemba-Zoltowska, E. Bocian, O. Rosiek and J. Sablinski (1980) on chromosome aberrations in irradiated human lymphocytes; comments are made on results derived from a an iteratively reweighted least squares procedure instead of the ordinary unweighted least squares method to establish first and second order dose-response curves for dicentric and centric rings. (U.K.)

  7. In vitro studies on chemoprotective effect of Purnark against benzo(a)pyrene-induced chromosomal damage in human lymphocytes.

    Ghaisas, S D; Bhide, S V

    1994-01-01

    Human lymphocytes were used as an assay system to test chemopreventive activity of natural products. Purnark, a mixture of extracts of turmeric, betel leaf and catechu, was tested for its chemoprotective activity against BP induced DNA damage. Sister chromatid exchange and micronuclei were used as markers to assess the protective activity of Purnark. Purnark gave 50-60% protection against BP induced SCEs and micronuclei. Purnark at 100 micrograms dose did not show any genotoxicity.

  8. Sister-chromatid exchange induced by X-ray of human lymphocytes and the effect of L-crysteine

    Abramovski, I.; Vorsanger, G.; Hirschhorn, K.

    1978-01-01

    A staining technique that detects sister-chromatid exchanges (SCEs) has been used to examine the response of human lymphocyte chromosomes to various dosages of X-irradiation. The SCE frequency was markedly increased following irradiation. However, the increase was of a significantly smaller magnitude when irradiation occurred in the presence of an antimutagenic agent. Scoring SCEs may provide a useful technique for assaying the mutagenic effects of environmental carcinogens as well as the protective effects of antimutagenic agents. (Auth.)

  9. Conjugated Bilirubin Triggers Anemia by Inducing Erythrocyte Death

    Lang, Elisabeth; Gatidis, Sergios; Freise, Noemi F; Bock, Hans; Kubitz, Ralf; Lauermann, Christian; Orth, Hans Martin; Klindt, Caroline; Schuier, Maximilian; Keitel, Verena; Reich, Maria; Liu, Guilai; Schmidt, Sebastian; Xu, Haifeng C; Qadri, Syed M; Herebian, Diran; Pandyra, Aleksandra A; Mayatepek, Ertan; Gulbins, Erich; Lang, Florian; Häussinger, Dieter; Lang, Karl S; Föller, Michael; Lang, Philipp A

    2015-01-01

    Hepatic failure is commonly associated with anemia, which may result from gastrointestinal bleeding, vitamin deficiency, or liver-damaging diseases, such as infection and alcohol intoxication. At least in theory, anemia during hepatic failure may result from accelerated clearance of circulating erythrocytes. Here we show that bile duct ligation (BDL) in mice leads to severe anemia despite increased reticulocyte numbers. Bilirubin stimulated suicidal death of human erythrocytes. Mechanistically, bilirubin triggered rapid Ca2+ influx, sphingomyelinase activation, formation of ceramide, and subsequent translocation of phosphatidylserine to the erythrocyte surface. Consistent with our in vitro and in vivo findings, incubation of erythrocytes in serum from patients with liver disease induced suicidal death of erythrocytes in relation to their plasma bilirubin concentration. Consistently, patients with hyperbilirubinemia had significantly lower erythrocyte and significantly higher reticulocyte counts compared to patients with low bilirubin levels. Conclusion: Bilirubin triggers suicidal erythrocyte death, thus contributing to anemia during liver disease. (Hepatology 2015;61:275–284) PMID:25065608

  10. Influence of occupational exposure to pesticides on lymphocytes responses to environment and UV. Report from the EC Project ERBIC 15CT 960300 'Pesticide Effects on Humans'

    2000-01-01

    The report presented studies of the genotoxic influence of occupational exposure to pesticides on human lymphocytes. The susceptibility of the cells to UV-C radiation and repair capacities of DNA damages were examined

  11. Exosomes from Human Immunodeficiency Virus Type 1 (HIV-1)-Infected Cells License Quiescent CD4+ T Lymphocytes To Replicate HIV-1 through a Nef- and ADAM17-Dependent Mechanism

    Arenaccio, Claudia; Chiozzini, Chiara; Columba-Cabezas, Sandra; Manfredi, Francesco; Affabris, Elisabetta; Baur, Andreas; Federico, Maurizio

    2014-01-01

    Resting CD4+ T lymphocytes resist human immunodeficiency virus (HIV) infection. Here, we provide evidence that exosomes from HIV-1-infected cells render resting human primary CD4+ T lymphocytes permissive to HIV-1 replication. These results were obtained with transwell cocultures of HIV-1-infected cells with quiescent CD4+ T lymphocytes in the presence of inhibitors of exosome release and were confirmed using exosomes purified from supernatants of HIV-1-infected primary CD4+ T lymphocytes. We...

  12. Cytosine arabinoside enhancement of gamma irradiation induced mutations in human T-lymphocytes

    O'Neill, J.P.; Sullivan, L.M.; Hunter, T.C.; Nicklas, J.A.

    1991-01-01

    The frequency of 6-thioguanine resistant (TGr) mutants induced in human G0 phase T-lymphocytes by 200 cGy of gamma irradiation is greatly enhanced by incubation with cytosine arabinoside (ara-C) after irradiation. The mutant frequency increased with increasing incubation time in ara-C for up to 2 hr. This mutation induction required a phenotypic expression time of 5-8 days mass culture growth, similar to that found with mutants induced by 300 cGy of irradiation alone. Southern blot analysis of 40 isolated mutant clones revealed 8 independent mutations by T-cell receptor (TCR) gene rearrangement patterns. Four of these eight showed hprt gene structural alterations (0.50). An alternative method to allow phenotypic expression was developed to minimize the isolation of hprt/TCR sibling mutants. The use of in situ expression in the microtiter dish wells resulted in the isolation of 17 independent mutations in 19 mutant clones. Ten of these 17 mutations showed hprt structural alterations (0.59). The high fraction of mutations involving structural alterations detected by Southern blot analysis is consistent with the known induction of chromosome aberrations by irradiation plus ara-C treatment. We propose that both the increase in Mf and the increase in the incidence of hprt gene structural alterations are due to the accumulation of strand breaks in repairing regions of DNA under these conditions of ara-C induced inhibition of repair. We further propose that upon release of the ara-C inhibition, these repairing regions can interact to yield both gene mutations and chromosome aberrations

  13. Induction of micronuclei in human and mouse lymphocytes irradiated with gamma radiation and effect of panax ginseng C. A. Meyer

    Kim, Sung Ho; Oh, Heon; Lee, Song Eun [Chonnam National Univ., Kwangju (Korea, Republic of); Lee, Yun Sil; Kim, Tae Hwan [Korea Cancer Center Hospital, Seoul (Korea, Republic of); Jeong, Kyu Sik [Korea Research Institute of Bioscience and Biotechnology, Taejon (Korea, Republic of); Ryu, Si Yun [Chungnam National Univ., Taejon (Korea, Republic of)

    1997-09-01

    The frequencies of {gamma}-ray-induced micronuclei (MN) in Cytokinesis-Blocked (CB) lymphocytes at several doses were measured in three donors of human and C57BL/6 mice. Measurements performed after irradiation showed a dose-related increases in MN frequency in each of the donors studied. The relative sensitivity of mouse in Spleen Lymphocytes (SLs) compared with human Peripheral Blood Lymphocytes (PBLs) was estimated by best fitting linear-quadratic model based on the radiation-induced MN data over the range from 0 cGy to 400 cGy. In the case of MN frequency with 0.2 per CB cell, the relative sensitivity of mouse SLs was 1.67. Compared with the radiation-induced MN formation in the PBLs of human, the SLs of mouse were more radiosensitive. Using this MN assay with human PBLs and mouse SLs, studies were performed to determine whether the water fraction of ginseng (Panax ginseng C.A.Meyer)against radiation-induced MN in human PBLs after in vitro irradiation (3Gy) and in SLs of C57BL/6 mice after in vivo irradiation (3Gy). The frequency of MN in human PBLs was reduced by water fraction of ginseng (0.5mg/ml of medium) both pre-and post treatment (p<0.01) in vitro. In addition, the frequency of MN in mouse SLs was also reduced by pretreatment of ginseng (2mg/ml of drinking water for 7 days) in vivo.

  14. Influence of some DNA-alkylating drugs on thermal stability, acid and osmotic resistance of the membrane of whole human erythrocytes and their ghosts.

    Ivanov, I T; Gadjeva, V

    2000-09-01

    Human erythrocytes and their resealed ghosts were alkylated under identical conditions using three groups of alkylating antitumor agents: mustards, triazenes and chloroethyl nitrosoureas. Osmotic fragility, acid resistance and thermal stability of membranes were changed only in alkylated ghosts in proportion to the concentration of the alkylating agent. All the alkylating agents decreased acid resistance in ghosts. The clinically used drugs sarcolysine, dacarbazine and lomustine all decreased osmotic fragility and thermal stability of ghost membranes depending on their lipophilicity. DM-COOH did not decrease osmotic fragility and thermal stability of ghost membranes, while NEM increased thermal stability of membranes. The preliminary but not subsequent treatment of ghosts with DM-COOH fully abolished the alkylation-induced thermal labilization of ghost membrane proteins while NEM had a partial effect only. The present study gives direct evidence that alkylating agents, having a high therapeutic activity against malignant growth, bind covalently to proteins of cellular membranes.

  15. Gamma-radiation-induced chromosal aberration in human lymphocytes: dose-rate effects in stimulated and non-stimulated cells

    Liniecki, J.; Bajerska, A.; Wyszynska, K.; Cisowska, B.

    1977-01-01

    Stimulated and non-stimulated human peripheral blood lymphocytes were irradiated acutely and chronically, over 24 h. Dose-effect relationships for dicentric chromosomes were established and various models were fitted to the data. At prolonged irradiations, the yield decreased in basic agreement with the linear-quadratic model of aberration induction. Dose-protraction experiments on PHA + and PHA - lymphocytes, irradiated under various conditions of oxygenation and suspension (culture medium, whole blood) showed that the rejoining time increased from about 3 h in non-stimulated cells to about 10 h after PHA stimulation, and that this retarded rejoining was most likely due to blastic transformation itself and not to other conditions of irradiation

  16. In vitro effect of the antimalarial drug proguanil hydrochloride on viability and DNA damage in human peripheral blood lymphocytes.

    Gajski, Goran; Dinter, Domagoj; Garaj-Vrhovac, Vera

    2010-11-01

    This study aimed to evaluate the effect of proguanil, a chemical substance used for treatment and prevention of malaria on viability and DNA integrity in human lymphocytes in vitro. Two different concentrations of proguanil obtained from the plasma concentrations were used: 130ng/ml used for prophylactic treatment and 520ng/ml used in treatment of malaria. Testing was done with and without metabolic activation. Viability of lymphocytes decreased in time and dose dependent manner. Comet assay parameters showed similar effects, indicating that some damage to DNA molecule can occur. Frequency of sister chromatid exchanges did not show significant deviation from the control samples. As for the proliferation kinetics no significant changes were noticed. Since majority of DNA damaging effect is induced after metabolic activation it is to be concluded that activity of proguanil is dependent upon the active metabolite cycloguanil and that monitoring should be conducted especially among frequent travellers. Copyright © 2010 Elsevier B.V. All rights reserved.

  17. Studies on bystander effects of 14MeV neutrons in human blood lymphocytes using CBMN assay

    Bakkiam, D.; Arul Anantha Kumar, A.; Sonwani, Swetha; Alaguraja, E.; Mathiyarasu, R.; Baskaran, R.; Venkatraman, B.

    2018-01-01

    Radiation induced Bystander Effects (RIBE) in cells generally describes the phenomenon that non-irradiated cells respond as if they have themselves been irradiated upon receiving signals from directly irradiated cells, either through partnering or medium transfer. While it has been well established that bystander effects could be induced by gamma radiation and alpha-particle radiation it is still a question whether neutrons induce bystander effects or not. In view of this, experiments were carried out to quantify cytogenetic damage in human blood lymphocytes induced by neutron directly and indirectly i.e. RIBE through medium transfer method. Cytokinesis Blocked MicroNucleus (CBMN) assay was used to study DNA damage events wherein micronuclei (MN) were scored in binucleated cells. Results of MN frequency in neutron direct and indirect irradiated blood lymphocytes (bystander samples) are compared

  18. Gamma radiation induced chromosal aberration in human lymphocytes: dose-rate effects in stimulated and non-stimulated cells

    Liniecki, J; Bajerska, A; Wyszynska, K [School of Medicine, Lodz (Poland). Div. of Nuclear Medicine and Radiobiology. Medical Research Center; Cisowska, B [Copernicus Municipal Hospital, Lodz (Poland). Oncology Center. Radiotherapy Dept.

    1977-05-01

    Stimulated and non-stimulated human peripheral blood lymphocytes were irradiated acutely and chronically, over 24 h. Dose-effect relationships for dicentric chromosomes were established and various models were fitted to the data. At prolonged irradiations, the yield decreased in basic agreement with the linear-quadratic model of aberration induction. Dose-protraction experiments on PHA/sup +/ and PHA/sup -/ lymphocytes, irradiated under various conditions of oxygenation and suspension (culture medium, whole blood) showed that the rejoining time increased from about 3 h in non-stimulated cells to about 10 h after PHA stimulation, and that this retarded rejoining was most likely due to blastic transformation itself and not to other conditions of irradiation.

  19. Inhibition of human lymphocyte proliferation and cleavage of interleukin-2 by Pseudomonas aeruginosa proteases

    Theander, T G; Kharazmi, A; Pedersen, B K

    1988-01-01

    This study was undertaken to determine the effect of Pseudomonas aeruginosa alkaline protease (AP) and elastase (ELA) on human lymphocyte function. AP at 50 micrograms/ml and ELA at 12 micrograms/ml caused a 50% inhibition of phytohemagglutinin-induced proliferation. There was no difference...... in the effect of proteases on CD4- and CD8-positive cells. To determine the effect of proteases on interleukin-2 (IL-2)-induced cell proliferation, the proteases and IL-2 were added to the IL-2-dependent CTLL-2 cell line. AP and ELA inhibited the proliferation of these cells. When IL-2 was added in excess......, the inhibition was partly reversed. ELA at 10 micrograms/ml cleaved IL-2, as judged by size chromatography of a reaction mixture containing 125I-labeled IL-2 and the proteases. The ELA-digested IL-2 exhibited a reduced binding capacity to IL-2 receptors on the lymphocytes. Furthermore, treatment...

  20. An alternative approach to studying the effects of ZnO nanoparticles in cultured human lymphocytes: combining electrochemistry and genotoxicity tests.

    Branica, Gina; Mladinić, Marin; Omanović, Dario; Želježić, Davor

    2016-12-01

    Nanoparticle use has increased radically raising concern about possible adverse effects in humans. Zinc oxide nanoparticles (ZnO NPs) are among the most common nanomaterials in consumer and medical products. Several studies indicate problems with their safe use. The aim of our study was to see at which levels ZnO NPs start to produce adverse cytogenetic effects in human lymphocytes as an early attempt toward establishing safety limits for ZnO NP exposure in humans. We assessed the genotoxic effects of low ZnO NP concentrations (1.0, 2.5, 5, and 7.5 μg mL-1) in lymphocyte cultures over 14 days of exposure. We also tested whether low and high-density lymphocytes differed in their ability to accumulate ZnO NPs in these experimental conditions. Primary DNA damage (measured with the alkaline comet assay) increased with nanoparticle concentration in unseparated and high density lymphocytes. The same happened with the fragmentation of TP53 (measured with the comet-FISH). Nanoparticle accumulation was significant only with the