Science.gov

Sample records for adherent human polymorphonuclear

  1. Differential effects of nylon fibre adherence on the production of superoxide anion by human polymorphonuclear neutrophilic granulocytes stimulated with chemoattractants, ionophore A23187 and phorbol myristate acetate.

    PubMed Central

    Kownatzki, E; Uhrich, S

    1987-01-01

    Human polymorphonuclear neutrophilic granulocytes were made adherent by passing them over protein-coated nylon fibre columns and compared with suspended cells for their production of superoxide anion as measured by cytochrome C reduction. The cells were stimulated with chemotactic factors, the ionophore A 23187, and the tumour promoter phorbol myristate acetate. There was no increased O2-. production by adherent cells in the absence of a stimulus. Adherent cells produced considerably higher amounts of superoxide than suspended cells when stimulated with formyl-methionyl-leucyl-phenylalanine, ionophore A 23187, C5a, C5adesArg, and the platelet activating factor 1-o-alkyl-2-acetyl-sn-glycero-3-phosphorylcholine. In contrast, stimulation with phorbol myristate acetate did not result in higher superoxide release from adherent than from suspended cells, and leukotriene B4 and a mononuclear cell-derived chemotaxin did not stimulate either cell to release significant amounts of superoxide. It is suggested that the augmented production of oxygen radicals with certain stimuli contributes to inflammatory symptoms in situations involving adherent granulocytes. PMID:2820637

  2. Lipopolysaccharide-dependent enhancement of adherence-mediated chemiluminescence response of polymorphonuclear leukocytes.

    PubMed

    Dwenger, A; Schweitzer, G; Funck, M

    1988-01-01

    Adherence of resting polymorphonuclear leukocytes to nylon fibre increased the chemiluminescence response (CL) from 99,400 to 910,300 cpm/25,000 PMNL. This effect could be amplified by lipopolysaccharide (LPS) priming of granulocytes in a dose-dependent fashion. The results of nylon fibre adherence experiments suggest an in vitro model that might approximate certain conditions of in vivo PMNL-endothelial adherence and respiratory burst activation, and these reactions of polymorphonuclear leukocytes may contribute to the pathomechanisms of the Adult Respiratory Distress Syndrome. PMID:3213589

  3. Intracellular Penetration and Activity of Gemifloxacin in Human Polymorphonuclear Leukocytes

    PubMed Central

    García, Isabel; Pascual, Alvaro; Ballesta, Sofía; Joyanes, Providencia; Perea, Evelio J.

    2000-01-01

    The intracellular penetration and activity of gemifloxacin in human polymorphonuclear leukocytes (PMN) were evaluated. Gemifloxacin reached intracellular concentrations eight times higher than extracellular concentrations. The uptake was rapid, reversible, and nonsaturable and was affected by environmental temperature, cell viability, and membrane stimuli. At therapeutic extracellular concentrations, gemifloxacin showed intracellular activity against Staphylococcus aureus. PMID:11036051

  4. Polymorphonuclear leucocytes in Crohn's disease and ulcerative proctocolitis: association between enhanced adherence to nylon fibre and disease variables.

    PubMed

    Cason, J; Ainley, C C; Wolstencroft, R A; Thompson, R P

    1988-03-01

    The adherence of polymorphonuclear leucocytes (PMN) to nylon fibre was investigated in patients with Crohn's disease, ulcerative proctocolitis, and anorexia nervosa, and compared with changes of circulating PMNs, C reactive protein concentrations, erythrocyte sedimentation rates, and clinical assessment of disease activity. PMN adherence was in excess of the maximum value detected for healthy subjects in 14 of 25 patients with Crohn's disease and two of 10 with proctocolitis, but it was within the normal range for all eight with anorexia nervosa. High adherence in Crohn's disease, however, was not associated with quantitative or qualitative changes of PMN populations, absolute concentrations of C reactive protein, erythrocyte sedimentation rates, disease severity, drug regimens, malnutrition, or zinc deficiency. High PMN adherence in Crohn's disease may therefore reflect the activation in vivo of normal PMN by humoral factors. PMID:3360954

  5. Effect of plastic catheters on the phagocytic activity of human polymorphonuclear leukocytes.

    PubMed

    López-López, G; Pascual, A; Perea, E J

    1990-05-01

    The effect of five kinds of plastic catheters (polyvinyl chloride, Teflon, polyurethane, Vialon and siliconized latex) on the phagocytic and bactericidal function of human polymorphonuclear leukocytes was evaluated. In the presence of the polyvinyl chloride, Teflon and siliconized latex catheters, superoxide radical production by polymorphonuclear leukocytes was significantly inhibited. The effect of the siliconized latex catheter was presumably mediated by products eluted from the catheter into the medium, since the incubation of polymorphonuclear leukocytes in eluates obtained from the incubation of this catheter in buffer induced a similar inhibitory effect. This phenomenon was not observed with polyurethane or Vialon catheters. Neither the catheters evaluated nor their eluates affected the uptake of opsonized Staphylococcus aureus by human polymorphonuclear leukocytes. It is concluded that the polyvinyl chloride, Teflon and siliconized latex catheters used in this study could impair the respiratory burst of human polymorphonuclear leukocytes. PMID:2164932

  6. Phospholipid turnover during phagocytosis in human polymorphonuclear leucocytes

    PubMed Central

    García Gil, Merche; Alonso, Fernando; Alvarez Chiva, Vicente; Sánchez Crespo, Mariano; Mato, José M.

    1982-01-01

    We have previously observed that the phagocytosis of zymosan particles coated with complement by human polymorphonuclear leucocytes is accompanied by a time- and dose-dependent inhibition of phosphatidylcholine synthesis by transmethylation [García Gil, Alonso, Sánchez Crespo & Mato (1981) Biochem. Biophys. Res. Commun. 101, 740–748]. The present studies show that phosphatidylcholine synthesis by a cholinephosphotransferase reaction is enhanced, up to 3-fold, during phagocytosis by polymorphonuclear cells. This effect was tested by both measuring the incorporation of radioactivity into phosphatidylcholine in cells labelled with [Me-14C]choline, and by assaying the activity of CDP-choline:diacylglycerol cholinephosphotransferase. The time course of CDP-choline:diacylglycerol cholinephosphotransferase activation by zymosan mirrors the inhibition of phospholipid methyltransferase activity previously reported. The extent of incorporation of radioactivity into phosphatidylcholine induced by various doses of zymosan correlates with the physiological response of the cells to this stimulus. This effect was specific for phosphatidylcholine, and phosphatidyl-ethanolamine turnover was not affected by zymosan. The purpose of this enhanced phosphatidylcholine synthesis is not to provide phospholipid molecules rich in arachidonic acid. The present studies show that about 80% of the arachidonic acid generated in response to zymosan derives from phosphatidylinositol. A transient accumulation of arachidonoyldiacylglycerol has also been observed, which indicates that a phospholipase C is responsible, at least in part, for the generation of arachidonic acid. Finally, isobutylmethylxanthine and quinacrine, inhibitors of phosphatidylinositol turnover, inhibit both arachidonic acid generation and phagocytosis, indicating a function for this pathway during this process. PMID:6181780

  7. Uptake of antibiotics by human polymorphonuclear leukocyte cytoplasts

    SciTech Connect

    Hand, W.L.; King-Thompson, N.L. , Decatur, GA )

    1990-06-01

    Enucleated human polymorphonuclear leukocytes (PMN cytoplasts), which have no nuclei and only a few granules, retain many of the functions of intact neutrophils. To better define the mechanisms and intracellular sites of antimicrobial agent accumulation in human neutrophils, we studied the antibiotic uptake process in PMN cytoplasts. Entry of eight radiolabeled antibiotics into PMN cytoplasts was determined by means of a velocity gradient centrifugation technique. Uptakes of these antibiotics by cytoplasts were compared with our findings in intact PMN. Penicillin entered both intact PMN and cytoplasts poorly. Metronidazole achieved a concentration in cytoplasts (and PMN) equal to or somewhat less than the extracellular concentration. Chloramphenicol, a lipid-soluble drug, and trimethoprim were concentrated three- to fourfold by cytoplasts. An unusual finding was that trimethroprim, unlike other tested antibiotics, was accumulated by cytoplasts more readily at 25 degrees C than at 37 degrees C. After an initial rapid association with cytoplasts, cell-associated imipenem declined progressively with time. Clindamycin and two macrolide antibiotics (roxithromycin, erythromycin) were concentrated 7- to 14-fold by cytoplasts. This indicates that cytoplasmic granules are not essential for accumulation of these drugs. Adenosine inhibited cytoplast uptake of clindamycin, which enters intact phagocytic cells by the membrane nucleoside transport system. Roxithromycin uptake by cytoplasts was inhibited by phagocytosis, which may reduce the number of cell membrane sites available for the transport of macrolides. These studies have added to our understanding of uptake mechanisms for antibiotics which are highly concentrated in phagocytes.

  8. Neisseria gonorrhoeae suppresses the oxidative burst of human polymorphonuclear leukocytes

    PubMed Central

    Criss, Alison K.; Seifert, H. Steven

    2008-01-01

    Symptomatic infection with Neisseria gonorrhoeae (Gc) results in a potent polymorphonuclear leukocyte (PMN)-driven inflammatory response, but the mechanisms by which Gc withstands PMN attack are poorly defined. Here we report that Gc can suppress the PMN oxidative burst, a central component of the PMN antimicrobial arsenal. Primary human PMNs remained viable after exposure to liquid-grown, exponential-phase, opacity-associated protein (Opa)-negative Gc of strains FA1090 and MS11 but did not generate reactive oxygen species (ROS), even after bacterial opsonization. Liquid-grown FA1090 Gc expressing OpaB, an Opa protein previously correlated with PMN ROS production, elicited a minor PMN oxidative burst. PMN ROS production in response to Opa− and OpaB+ Gc was markedly enhanced if bacteria were agar-grown or if liquid-grown bacteria were heat killed. Liquid-grown Opa- Gc inhibited the PMN oxidative burst elicited by isogenic dead bacteria, formylated peptides or Staphylococcus aureus but did not inhibit PMN ROS production by OpaB+ Gc or phorbol esters. Suppression of the oxidative burst required Gc-PMN contact and bacterial protein synthesis but not phagocytosis. These results suggest that viable Gc directly inhibits PMN signaling pathways required for induction of the oxidative burst, which may contribute to gonococcal pathogenesis during inflammatory stages of gonorrheal disease. PMID:18684112

  9. Aggregation of human polymorphonuclear leucocytes during phagocytosis of bacteria.

    PubMed Central

    Henricks, P A; van der Tol, M E; Verhoef, J

    1984-01-01

    The process of aggregation of human polymorphonuclear leucocytes (PMN) during the uptake of bacteria was studied. Radiolabelled S. aureus were opsonized in different sera, washed, resuspended in buffer and added to the PMN. Uptake of the bacteria and aggregation of the PMN were measured simultaneously. Maximal aggregation occurred within 6 min, when 5 X 10(6) PMN had phagocytosed 2.5 X 10(8) S. aureus. Also the effects of serum concentrations and different sera for opsonization of the bacteria on PMN aggregation were studied. Despite normal uptake, aggregation of PMN was low when bacteria were opsonized in complement-deficient sera. Furthermore when PMN were treated with pronase to inactivate complement receptors on the cell surface of the PMN, and bacteria preopsonized in immune serum were added, no change in uptake occurred, although the degree of aggregation halved compared to control PMN. So, interaction between the bacteria and the complement receptor of the PMN cell membrane is needed for triggering the process of aggregation. By using dansylcadaverin and diphenylamine to modulate lysosomal enzyme release, azide or PMN from a chronic granulomatous disease patient to study the effect of the formation of oxygen species, and theophylline, DB-cAMP or 8 Br-cAMP to increase cAMP levels, it was concluded that aggregation of PMN during phagocytosis was not dependent on oxygen metabolism, degranulation or cAMP levels of PMN. PMID:6086503

  10. Mechanism Underlying Levofloxacin Uptake by Human Polymorphonuclear Neutrophils

    PubMed Central

    Vazifeh, Doina; Bryskier, André; Labro, Marie-Thérèse

    1999-01-01

    The mechanism of radiolabeled levofloxacin ([3H]levofloxacin) uptake by human polymorphonuclear neutrophils (PMNs) was investigated by a classical velocity centrifugation technique. PMNs were incubated with levofloxacin for 5 to 180 min under various conditions before centrifugation through an oil cushion. Radioactivity was measured in the cell pellet to determine the amount of cell-associated drug. The uptake of levofloxacin was moderate with a cellular concentration/extracellular concentration ratio of about 4 to 6. Levofloxacin accumulated in PMNs parallel to the extracellular concentration, without saturation, over the range of 2.5 to 200 mg/liter (linear regression analysis: r = 0.92; P < 0.001). The activation energy was low (36 ± 7.2 kJ/mol). Levofloxacin uptake was increased in Ca2+-depleted, EGTA-containing medium by approximately 33% (P = 0.022), while Ni2+, a Ca2+ channel inhibitor, inhibited it in a concentration-dependent manner, with the concentration that inhibited 50% of control uptake being approximately 2.65 mM. Verapamil (an l-type Ca2+ channel inhibitor) and other pharmacologic agents which modify Ca2+ homeostasis did not modify levofloxacin uptake. Interestingly, Ca2+ and Mg2+ inhibited levofloxacin uptake in a concentration-dependent manner. EGTA, Ni2+, and verapamil did not modify levofloxacin efflux; thapsigargin, a Ca2+ pool-releasing agent, modestly increased the intracellular retention of levofloxacin. In addition, contrary to other fluoroquinolones, probenecid at 1 to 10 mM did not modify either levofloxacin uptake or efflux. These data are consistent with a mechanism of passive accumulation of levofloxacin in PMNs. Extracellular Ca2+ and Mg2+ may influence the structural conformation of levofloxacin or the lipophilicity of PMN membranes, thus explaining their effect on levofloxacin uptake. PMID:9925513

  11. Influence of tetracyclines on human polymorphonuclear leukocyte function.

    PubMed Central

    Glette, J; Sandberg, S; Hopen, G; Solberg, C O

    1984-01-01

    Low concentrations of oxytetracycline, doxycycline, or minocycline (less than 10 micrograms/ml) did not influence in vitro polymorphonuclear leukocyte random migration, chemiluminescence, or glucose oxidation. At high concentrations of doxycycline or minocycline (greater than 10 micrograms/ml), chemiluminescence and glucose oxidation were impaired. High concentrations of doxycycline also reduced random migration. Oxytetracycline did not influence these functions in concentrations up to 100 micrograms/ml. The inhibiting effect of doxycycline and minocycline was abolished when 4 mM Mg2+ was added to the reaction mixture, and 4 mM Ca2+ partly restored minocycline-inhibited polymorphonuclear leukocyte functions. This indicates that the major effect of tetracyclines on in vitro polymorphonuclear leukocyte functions is mediated by their divalent cation chelating effect and that the results of in vitro experiments are highly dependent on the concentration of divalent cations in the reaction mixtures. The difference between the tetracyclines may be due to differences in lipid solubility, with solubility being highest for minocycline and lowest for oxytetracycline, or to different divalent cation chelating ability. PMID:6721468

  12. Analysis of cell locomotion. Contact guidance of human polymorphonuclear leukocytes.

    PubMed

    Matthes, T; Gruler, H

    1988-01-01

    The methods of statistical physics have been applied to the analysis of cell movement. Human polymorphonuclear leukocytes were exposed to different surfaces possessing parallel oriented physical structures (scratched glass surface, machine drilled aluminum surface, optical grid and stretched polyethylene foil) and cell migration was observed using time-lapse photography. We demonstrate that in cell migration along physical structures, referred to as contact guidance, two subgroups can be distinguished: 1) The nematic type where the cell size is large in relation to the grid distance of the undulate surface. 2) The smectic type where the cell size is small in relation to the grid distance of the substrate. Nematic contact guidance is characterized by an anisotropic random walk. In all substrates investigated the diffusion process parallel to the lines was faster than the diffusion process perpendicular to them. The angular dependent diffusion coefficient was described by an ellipse. Deviation from a circle defined an apolar order parameter, whose value was about 0.3. The amount of information which the cells collected from, the undulate surface was very low, between 0.1 and 0.2 bits. We demonstrate that cells do not recognize all the details of their surroundings and that their migration can be compared to the "groping around" of a short sighted man. The blurred environment can be described by a mean field whose strength is proportional to the apolar order parameter. It is argued that the anisotropic surface tension is the basic source for nematic contact guidance. Smectic contact guidance is characterized by an anisotropic random walk and is quantified by a density order parameter which is 0.28 in the case of the scratched glass surface of a Neubauer counting chamber. The information which the cells collect from their environment is very low (0.03 bits). The lines seen by the cell can be described by a mean field whose strength is proportional to the density oder

  13. Generation of slow-reacting substance (leukotrienes) by endotoxin and lipid A from human polymorphonuclear granulocytes.

    PubMed Central

    Bremm, K D; König, W; Spur, B; Crea, A; Galanos, C

    1984-01-01

    Leukotrienes were released from human polymorphonuclear granulocytes on incubation with endotoxins and lipid A. The analysis was performed by their smooth muscle contracting properties, reversed phase high-pressure liquid chromatography and radioimmunoassay for leukotrienes C4 and D4. The active component of the lipopolysaccharides seems to be the lipid A portion. PMID:6490085

  14. Fucose-binding Lotus tetragonolobus lectin binds to human polymorphonuclear leukocytes and induces a chemotactic response.

    PubMed

    VanEpps, D E; Tung, K S

    1977-09-01

    Fucose-binding L. tetragonolobus lectin to the surface of human polymorphonuclear leukocytes (PMN) and induces a chemotactic response. Both surface binding and chemotaxis are inhibited by free fucose but not by fructose, mannose, or galactose. The lectin-binding sites on PMN are unrelated to the A, B, or O blood group antigen. Utilization of this lectin should be a useful tool in isolating PMN membrane components and in analyzing the mechanism of neutrophil chemotaxis. PMID:330752

  15. Soil adherence to human skin

    SciTech Connect

    Driver, J.H.; Konz, J.J.; Whitmyre, G.K. )

    1989-12-01

    Dermal exposure to soils contaminated with toxic chemicals represents a potential public health hazard. These soils, contaminated with chemicals such as PCBs and dioxins, may be found at various locations throughout the US. Furthermore, dermal contact with pesticide-containing particles and contaminated soil particles is of importance for exposures to agricultural workers who reenter fields after pesticide application. With respect to dermal exposure to pesticide-contaminated particulate matter, several occurrences of human toxicity to ethyl parathion in citrus groves have been reported. These exposures resulted from dermal contact with high concentrations of the toxic transformation product paraoxon in soil dust contaminated as a result of application of pesticide to the overhead foliage of trees. To assess dermal exposure to chemically-contaminated soil at sites of concern, dermal adherence of soil must be determined prior to the assessment of dermal absorption. The purpose of the experiment reported herein was to determine the amount of soil (mg/cm{sup 2}) that adheres to adult hands under various soil conditions. These conditions include the type of soil, the organic content of the soil, and the particle size of the soil.

  16. Activation of human polymorphonuclear leucocytes by particulate zymosan is related to both its major carbohydrate components: glucan and mannan.

    PubMed

    Williams, J D; Topley, N; Alobaidi, H M; Harber, M J

    1986-05-01

    Unopsonized particulate zymosan and its major carbohydrate component glucan were phagocytosed under serum-free conditions by adherent polymorphonuclear leucocytes (PMN) in a dose- and time-dependent manner. Preincubation of PMN monolayers with mannan did not cause a reduction in the phagocytosis of either particle. The phagocytic response was inhibited by preincubation of the cells with trypsin at a concentration that did not inhibit the phagocytosis of sheep erythrocytes coated with IgG or of latex particles. Homology of the recognition mechanisms for glucan and zymosan was confirmed when cells cultured on fixed glucan or on fixed zymosan failed to ingest either particle to more than 40% of control phagocytosis. Similarly, zymosan and glucan activated PMN in suspension, in a dose- and time-dependent manner, to generate reactive oxygen species which were measured as luminol-dependent chemiluminescence (CL). There was, however, a four-fold greater CL response to zymosan. Preincubation of PMN with mannan resulted in a significantly decreased CL response to zymosan, while the response to glucan was unaffected. The CL response was also sensitive to a range of concentrations of trypsin. In contrast, two other complex polysaccharide particles (barley-derived beta-glucan and algae-derived laminarin) were not phagocytosed by PMN, nor did they cause the generation of CL, despite the fact that they possessed the capacity, in common with zymosan and glucan, to activate the alternative pathway of complement. The identification of a trypsin-sensitive recognition mechanism on the surface of human PMN for unopsonized zymosan and glucan represents a response not hitherto characterized. Furthermore, our data indicate that the phagocytosis of unopsonized zymosan by human PMN is dependent primarily on its glucan content, but that its capacity to activate the respiratory burst may involve mannan and the recruitment of a second cell surface recognition mechanism. PMID:3710519

  17. CD66 carcinoembryonic antigens mediate interactions between Opa-expressing Neisseria gonorrhoeae and human polymorphonuclear phagocytes.

    PubMed

    Gray-Owen, S D; Dehio, C; Haude, A; Grunert, F; Meyer, T F

    1997-06-16

    Colonization of urogenital tissues by the human pathogen Neisseria gonorrhoeae is characteristically associated with purulent exudates of polymorphonuclear phagocytes (PMNs) containing apparently viable bacteria. Distinct variant forms of the phase-variable opacity-associated (Opa) outer membrane proteins mediate the non-opsonized binding and internalization of N. gonorrhoeae by human PMNs. Using overlay assays and an affinity isolation technique, we demonstrate the direct interaction between Opa52-expressing gonococci and members of the human carcinoembryonic antigen (CEA) family which express the CD66 epitope. Gonococci and recombinant Escherichia coli strains synthesizing Opa52 showed specific binding and internalization by transfected HeLa cell lines expressing the CD66 family members BGP (CD66a), NCA (CD66c), CGM1 (CD66d) and CEA (CD66e), but not that expressing CGM6 (CD66b). Bacterial strains expressing either no opacity protein or the epithelial cell invasion-associated Opa50 do not bind these CEA family members. Consistent with their different receptor specificities, Opa52-mediated interactions could be inhibited by polyclonal anti-CEA sera, while Opa50 binding was instead inhibited by heparin. Using confocal laser scanning microscopy, we observed a marked recruitment of CD66 antigen by Opa52-expressing gonococci on both the transfected cell lines and infected PMNs. These data indicate that members of the CEA family constitute the cellular receptors for the interaction with, and internalization of, N. gonorrhoeae. PMID:9218786

  18. The essential oil of bergamot stimulates reactive oxygen species production in human polymorphonuclear leukocytes.

    PubMed

    Cosentino, Marco; Luini, Alessandra; Bombelli, Raffaella; Corasaniti, Maria T; Bagetta, Giacinto; Marino, Franca

    2014-08-01

    Bergamot (Citrus aurantium L. subsp. bergamia) essential oil (BEO) is used in folk medicine as an antiseptic and anthelminthic and to facilitate wound healing. Evidence indicates that BEO has substantial antimicrobial activity; however its effects on immunity have never been examined. We studied the effects of BEO on reactive oxygen species (ROS) production in human polymorphonuclear leukocytes (PMN) and the role of Ca(2+) in the functional responses evoked by BEO in these cells. Results show that BEO increased intracellular ROS production in human PMN, an effect that required the contribution of extracellular (and, to a lesser extent, of intracellular) Ca(2+) . Bergamot essential oil also significantly increased ROS production induced by the chemotactic peptide N-formyl-Met-Leu-Phe and reduced the response to the protein kinase C activator phorbol myristate acetate. In conclusion, this is the first report showing the ability of BEO to increase ROS production in human PMN. This effect could both contribute to the activity of BEO in infections and in tissue healing as well as underlie an intrinsic proinflammatory potential. The relevance of these findings for the clinical uses of BEO needs careful consideration. PMID:24458921

  19. Inhibition of eicosanoid formation in human polymorphonuclear leukocytes by high concentrations of magnesium ions.

    PubMed

    Ludwig, P; Petrich, K; Schewe, T; Diezel, W

    1995-12-01

    The cutaneous antiinflammatory action of Dead-Sea brine is thought to be due to magnesium ions. To elucidate their mode of action, we studied the influence of isotonic solutions containing high concentrations of Mg2+ (up to 115mM) on the formation of 5-lipoxygenase-derived eicosanoids in human polymorphonuclear leukocytes. The cells were stimulated by either ionophore A23187 or the chemotactic peptide N-formyl-L-methionyl-L-leucyl-L-phenylalanine. We observed a pronounced inhibition of the formation of leukotriene B4 and 5-hydroxyeicosatetraenoic acid from either added [1-14C] or endogenously liberated arachidonic acid. In the latter case, the sum of arachidonic acid and its oxygenation products was also markedly diminished. The inhibitory effects of Mg2+ depended in a reciprocal manner on the concentration of Ca2+ in the incubation medium. An unspecific damage to cells as reason for the inhibitory effects was excluded. Human recombinant 5-lipoxygenase was also inhibited by Mg2+ in the same concentration range (IC50 16 mM). These data suggest that high concentrations of Mg2+ inhibit the eicosanoid metabolism both at the level of the liberation of arachidonic acid and by direct inhibition of the 5-lipoxygenase enzyme. PMID:9072050

  20. Abnormalities of polymorphonuclear leukocyte function associated with a heritable deficiency of high molecular weight surface glycoproteins (GP138): common relationship to diminished cell adherence.

    PubMed Central

    Anderson, D C; Schmalstieg, F C; Arnaout, M A; Kohl, S; Tosi, M F; Dana, N; Buffone, G J; Hughes, B J; Brinkley, B R; Dickey, W D

    1984-01-01

    Investigations of polymorphonuclear leukocyte (PMN) function were performed in a 5-yr-old white female with delayed umbilical cord separation, impaired pus formation, and a severe defect of PMN chemotaxis. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis demonstrated an almost total deficiency of a high molecular weight glycoprotein(s) (GP138) in the granule and membrane fractions of the patient's cells, and NaB3H4-galactose oxidase labeling demonstrated the absence of a major glycoprotein complex on the surface of her PMNs. Monoclonal antibodies (MAb) were employed in flow cytometry experiments to demonstrate that two previously characterized glycoproteins (Mo1 and LFA1) were undetectable on the surface of the patient's PMNs and monocytes. Immunoprecipitation of 125I-labeled patient cells with subunit specific MAbs confirmed that the alpha-subunits of Mo1 (155 kD) and LFA1 (177 kD) and their common beta-subunit (94 kD) were totally deficient. Functional analyses of patient PMNs demonstrated severe impairment of adherence- and adhesion-dependent cell functions including spreading, aggregation, orientation in chemotactic gradients, antibody-dependent cellular cytotoxicity, and phagocytosis of particles (Oil-Red-0-paraffin, zymosan) selectively opsonized with C3-derived ligands. Patient PMNs demonstrated a normal capacity to rosette with IgG or C3b-coated sheep erythrocytes, but rosette formation with C3bi-coated erythrocytes was profoundly diminished. Adhesion-independent functions including shape change, N-formyl-methionyl-leucyl-3H-phenylalanine binding, and O-2 generation or secretion elicited by soluble stimuli were normal. Membrane fluidity, surface charge, and microtubule assembly were also normal. These findings provide new evidence that critical PMN surface glycoproteins are required to facilitate multiple adhesion-dependent cellular functions of the inflammatory response. Images PMID:6746906

  1. Effect of complement and of the carbohydrate components of sputum on phagocytosis by human polymorphonuclear leucocytes

    PubMed Central

    Brogan, T. D.

    1964-01-01

    The phagocytic activity of human polymorphonuclear leucocyte preparations, which were free from plasma, has been estimated by direct determination under phase contrast of the number of living cells containing test particles. Spores of Aspergillus fumigatus were phagocytosed in the absence of added serum but phagocytosis of paraffin wax particles occurred only in the presence of serum containing the heat-labile and C′4 components of complement. In view of the unreactive nature of the paraffin hydrocarbons, it was considered unlikely that natural antibody played any part in the phenomenon. Although no phagocytosis of wax particles occurred in the absence of serum, almost 100 per cent of cells were phagocytic in preparations containing adequate concentrations of serum. It was therefore possible to determine the serum concentration necessary for 50 per cent of the polymorphs to phagocytose wax particles. By this means it was demonstrated that the addition of the carbohydrate components of sputum had a small but significant inhibitory effect on phagocytosis and that dextran had no such effect. The sputum mucoprotein depressed the complement titre of serum and this might have accounted for the reduction in the ability of a serum to promote phagocytosis when this complex was added. The sputum mucopolysaccharide had no such effect on the complement titre of serum and must have exerted its inhibitory action in some other way. ImagesFIG. 2 PMID:14239838

  2. Prostaglandin E2 inhibits apoptosis in human neutrophilic polymorphonuclear leukocytes: role of intracellular cyclic AMP levels.

    PubMed

    Ottonello, L; Gonella, R; Dapino, P; Sacchetti, C; Dallegri, F

    1998-08-01

    Human neutrophilic polymorphonuclear leukocytes (neutrophils) are terminally differentiated cells that die by undergoing apoptosis. At present, the intracellular pathways governing this process are only partially known. In particular, although the adenylate cyclase-dependent generation of cyclic AMP (cAMP) has been implicated in the triggering of apoptosis in lymphoid cells, the role of the intracellular cAMP pathway in neutrophil apoptosis remains controversial. In the present study, we found that two cAMP-elevating agents, prostaglandin E2 (PGE2) and the phosphodiesterase type IV inhibitor RO 20-1724, inhibit neutrophil apoptosis without inducing cell necrosis. When administered in combination, PGE2 and RO 20-1724 displayed additive effects. Moreover, neutrophil apoptosis was inhibited by a membrane-permeable analog of cAMP, dibutyryl-cAMP, in a dose-dependent manner. Finally, treatment of neutrophils with the protein kinase A inhibitor H-89 prevented PGE2- and RO 20-1724-induced inhibition of cell apoptosis. In conclusion, taking into account that PGE2 and other cAMP-elevating agents are well known downregulators of neutrophil functions, our results suggest that conditions favoring a state of functional rest, such as intracellular cAMP elevation, prolong the life span of neutrophils by delaying apoptosis. PMID:9694511

  3. Modulation of human lymphocyte mitogen responsiveness and interleukin-2 production by polymorphonuclear leukocytes.

    PubMed

    Lyte, M

    1990-06-01

    The response of human peripheral blood lymphocytes to the mitogenic lectins phytohemagglutinin (PHA) and pokeweed mitogen (PWM) was examined in the presence of autologous polymorphonuclear leukocytes (PMN). Experiments were performed at sub-optimal and optimal mitogen concentrations employing lymphocyte: PMN ratios over a three log cell concentration range. Increases of up to 25,000-fold in mitogen stimulated lymphocyte proliferation as determined by 3H-thymidine incorporation were observed in PMN supplemented lymphocyte cultures as compared to lymphocytes cultured in the absence of PMN or with irradiated lymphocytes serving as filler cells. Similar results were obtained for PHA stimulated IL-2 production. The degree of enhancement of lymphocyte reactivity by PMN was also shown to be dependent on the source of serum supplementation (autologous versus xenogeneic). These results indicate that cell ratio is a critical factor in examining lymphocyte-PMN interactions as well as serum supplementation used. Early reports which have indicated a suppressive or no effect of PMN on lymphocyte reactivity based on a single lymphocyte: PMN cell ratio may need to be re-evaluated. PMID:1967045

  4. Localization of NADH oxidase on the surface of human polymorphonuclear leukocytes by a new cytochemical method.

    PubMed

    Briggs, R T; Drath, D B; Karnovsky, M L; Karnovsky, M J

    1975-12-01

    The ultrastructural localization of NADH oxidase, a possible enzyme in the increased oxidative activity of polymorphonuclear leukocytes (PMN) during phagocytosis, was studied. A new cytochemical technique for the localization of H2O2, a product of NADH oxidase activity, was developed. Cerous ions, in the presence of peroxide, form an electron-dense precipitate. Resting and phagocytically stimulated PMN were exposed to cerous ions at pH 7.5 to demonstrate sites of NADH-dependent, cyanide-insensitive H2O2 production. Resting PMN exhibites slight activity on the plasma membrane; phagocytizing PMN had extensive deposits of reaction product localized within the phagosome and on the plasma membrane. Peroxide involvement was demonstrated by the inhibitory effect of catalase on cerium precipitation; the surface localization of the enzyme responsible was confirmed by using nonpenetrating inhibitors of enzymatic activity. A correlative study was performed with an NADH-dependent, tetrazolium-reduction system. As with cerium, formazan deposition on the surface of the cell was NADH dependent, cyanide insensitive, and stimulated by phagocytosis. Superoxide dismutase did not inhibit tetrazolium reduction, as observed cytochemically, indicating direct enzymatic dye reduction without superoxide interposition. These findings, combined with oxygen consumption studies on resting and stimulated PMN in the presence or absence of NADH, indicate that NADH oxidase is a surface enzyme in human PMN. It is internalized during phagocytosis and retains its peroxide-generating capacity within the phagocytic vacuole. PMID:407

  5. Group A streptococcal peptidoglycan-polysaccharide inhibits phagocytic activity of human polymorphonuclear leukocytes.

    PubMed Central

    Leong, P A; Cohen, M S

    1984-01-01

    Injection of sterile aqueous preparations of the peptidoglycan-polysaccharide of group A streptococci (PG-APS) produces chronic inflammation in several animal models. Chronic bacterial infection may be involved in some aspects of the pathogenesis of inflammation associated with the accumulation of PG-APS. Accordingly, the effect of PG-APS on human neutrophil (polymorphonuclear leukocyte [PMN]) bactericidal activity was studied with the supposition that this interaction may contribute to the inflammation observed. Concentrations of PG-APS greater than 10 micrograms/ml inhibited the ability of PMNs to kill Staphylococcus aureus. This inhibition was not due to a cytotoxic effect of PG-APS on PMNs, nor did PG-APS inhibit PMN metabolism required for the formation of microbicidal oxygen reduction products. PG-APS concentrations of 10 micrograms/ml or greater in the presence of 10% normal serum inhibited the attachment of bacteria to PMNs by 49% as compared with control cell populations. The concentrations of PG-APS required to inhibit uptake of Staphylococcus aureus were identical to those required for inhibition of PMN bactericidal activity. This inhibition did not occur in the presence of serum-free medium or medium with sera that had been heated to inactivate complement. These results show that PG-APS interacts with serum to inhibit PMN-mediated killing of S. aureus, most probably by interfering with bacterial uptake. PMID:6378796

  6. Generation and secretion of eosinophilotactic activity from human polymorphonuclear neutrophils by various mechanisms of cell activation.

    PubMed Central

    König, W; Frickhofen, N; Tesch, H

    1979-01-01

    An eosinophil chemotactic factor(s) (ECF) can be generated from human polymorphonuclear neutrophils by the calcium ionophore, phagocytosis, arachidonic acid and hypotonic lysis. In kinetic studies it is observed that peak ECF activity is released prior to the maximum of lysosomal enzyme release with the calcium ionophore, phagocytosis and arachidonic acid, while under conditions of hypotonic exposure ECF activity appears after the maximum of enzyme release. The ECF obtained by hypotonic exposure shows a fluctuating pattern with sharp peaks and steep fall-offs in activity. The ECF-release for each stimulus is temperature dependent; extracellular calcium is required when the ionophore or phagocytosis are used as stimuli, while with arachidonic acid and hypotonic exposure no extracellular calcium is necessary for ECF-release. On Sephadex G-25 each preparation of ECF eluted in the low molecular weight range at approximately 500 daltons. Eosinophils can be deactivated and cross-deactivated with the various ECF-preparations indicating either a molecular identity or a common mode of action on eosinophils. PMID:437847

  7. Interaction of the two components of leukocidin from Staphylococcus aureus with human polymorphonuclear leukocyte membranes: sequential binding and subsequent activation.

    PubMed Central

    Colin, D A; Mazurier, I; Sire, S; Finck-Barbançon, V

    1994-01-01

    The sequential interaction between the two components S and F of leukocidin from Staphylococcus aureus and the membrane of human polymorphonuclear neutrophils has been investigated in the presence of 1 mM Ca2+. With 125I-labeled components, it has been shown that binding of the F component occurred only after binding of the S component. The kinetic constants of binding of both components were not statistically different (Kd, approximately 5 nM; Bm, approximately 35,000 molecules per cell), and both Hill coefficients were 1. The application of increasing concentrations of leukocidin provoked a dose-dependent secretion of the granule content, as determined by hexosaminidase and lysozyme activity measurements. Furthermore, the separate perfusion of S and F components on human polymorphonuclear neutrophils deposited on a filter induced secretion of the granules content only when the perfusion of the S component preceded that of the F component. We conclude, therefore, that (i) S-component binding is a prerequisite for F-component binding and for subsequent activation of polymorphonuclear neutrophils and (ii) there is a specific binding site for the S component in the plasma membrane. PMID:8039887

  8. Human polymorphonuclear leukocytes inhibit Aspergillus fumigatus conidial growth by lactoferrin-mediated iron depletion.

    PubMed

    Zarember, Kol A; Sugui, Janyce A; Chang, Yun C; Kwon-Chung, Kyung J; Gallin, John I

    2007-05-15

    Aspergillus fumigatus, a common mold, rarely infects humans, except during prolonged neutropenia or in cases of chronic granulomatous disease (CGD), a primary immunodeficiency caused by mutations in the NADPH oxidase that normally produces fungicidal reactive oxygen species. Filamentous hyphae of Aspergillus are killed by normal, but not CGD polymorphonuclear leukocytes (PMN); however, the few studies on PMN-mediated host defenses against infectious conidia (spores) of this organism have yielded conflicting results, some showing that PMN do not inhibit conidial growth, with others showing that they do, most likely using reactive oxygen species. Given that CGD patients are exposed daily to hundreds of viable A. fumigatus conidia, yet considerable numbers of them survive years without infection, we reasoned that PMN use ROS-independent mechanisms to combat Aspergillus. We show that human PMN from both normal controls and CGD patients are equipotent at arresting the growth of Aspergillus conidia in vitro, indicating the presence of a reactive oxygen species-independent factor(s). Cell-free supernatants of degranulated normal and CGD neutrophils both suppressed fungal growth and were found to be rich in lactoferrin, an abundant PMN secondary granule protein. Purified iron-poor lactoferrin at concentrations occurring in PMN supernatants (and reported in human mucosal secretions in vivo) decreased fungal growth, whereas saturation of lactoferrin or PMN supernatants with iron, or testing in the presence of excess iron in the form of ferritin, completely abolished activity against conidia. These results demonstrate that PMN lactoferrin sequestration of iron is important for host defense against Aspergillus. PMID:17475866

  9. Adhesion and migration of polymorphonuclear leukocytes across human brain microvessel endothelial cells are differentially regulated by endothelial cell adhesion molecules and modulate monolayer permeability.

    PubMed

    Wong, Donald; Prameya, Rukmini; Dorovini-Zis, Katerina

    2007-03-01

    The mechanisms by which polymorphonuclear leukocytes (PMN) cross the human blood-brain barrier have not been fully elucidated. Using a well characterized in vitro model of the human BBB, we examined the role of endothelial cell adhesion molecules on the adhesion and transendothelial migration of PMN across primary cultures of human brain microvessel endothelial cells (HBMEC). A small number of PMN (0.06%) adhered to unstimulated HBMEC, and the basal adhesion was not affected by anti-adhesion molecule antibodies. Treatment of HBMEC with tumor necrosis factor (TNF)-alpha resulted in increased PMN adhesion that was significantly inhibited by blocking antibodies to E-selectin and ICAM-1, but not VCAM-1 or PECAM-1. A very small number of adherent PMN migrated across unstimulated HBMEC monolayers. Migration increased 2 to 20 fold following stimulation of HBMEC with TNF-alpha. Monoclonal antibody blocking studies showed that PMN used ICAM-1, but not VCAM-1, E-selectin or PECAM-1 to move across activated monolayers. Anti-adhesion molecule antibodies did not diminish the basal PMN migration. Ultrastructurally, PMN often aggregated on top and between adjacent endothelial cells and adhered by first extending pseudopodia along the apical endothelial surface. They then flattened and inserted themselves between endothelial cells in order to migrate across the monolayers. At the end of the migration period, the cultures resumed their continuity with no evidence of disruption. Transendothelial migration of PMN decreased the transendothelial electrical resistance and increased the permeability to horseradish peroxidase, which penetrated alongside the migrating leukocytes. A blocking antibody to ICAM-1 that greatly decreased migration, had no effect on the permeability changes. These studies provide insights into the mechanisms that regulate the entry of PMN into the brain and the increased permeability of the BBB in CNS inflammation. PMID:17291598

  10. Mechanism of arachidonic acid liberation in platelet-activating factor-stimulated human polymorphonuclear neutrophils

    SciTech Connect

    Nakashima, S.; Suganuma, A.; Sato, M.; Tohmatsu, T.; Nozawa, Y. )

    1989-08-15

    Upon stimulation of human polymorphonuclear neutrophils with platelet-activating factor (PAF), arachidonic acid (AA) is released from membrane phospholipids. The mechanism for AA liberation, a key step in the synthesis of biologically active eicosanoids, was investigated. PAF was found to elicit an increase in the cytoplasmic level of free Ca2+ as monitored by fluorescent indicator fura 2. When (3H) AA-labeled neutrophils were exposed to PAF, the enhanced release of AA was observed with a concomitant decrease of radioactivity in phosphatidylinositol and phosphatidylcholine fractions. The inhibitors of phospholipase A2, mepacrine and 2-(p-amylcinnamoyl)-amino-4-chlorobenzoic acid, effectively suppressed the liberation of (3H)AA from phospholipids, indicating that liberation of AA is mainly catalyzed by the action of phospholipase A2. The extracellular Ca2+ is not required for AA release. However, intracellular Ca2+ antagonists, TMB-8 and high dose of quin 2/AM drastically reduced the liberation of AA induced by PAF, indicating that Ca2+ is an essential factor for phospholipase A2 activation. PAF raised the fluorescence of fura 2 at concentrations as low as 8 pM which reached a maximal level about 8 nM, whereas more than nM order concentrations of PAF was required for the detectable release of (3H)AA. Pretreatment of neutrophils with pertussis toxin resulted in complete abolition of AA liberation in response to PAF. However, the fura 2 response to PAF was not effectively inhibited by toxin treatment. In human neutrophil homogenate and membrane preparations, guanosine 5'-O-(thiotriphosphate) stimulated AA release and potentiated the action of PAF. Guanosine 5'-O-(thiodiphosphate) inhibited the effects of guanosine 5'-O-(thiotriphosphate).

  11. Identification and functional characterization of leukotriene B4 20-hydroxylase of human polymorphonuclear leukocytes.

    PubMed Central

    Soberman, R J; Harper, T W; Murphy, R C; Austen, K F

    1985-01-01

    A single reaction product was formed during the incubation of 1.5 microM (5S,12R)-dihydroxy-6,14-cis-8,10-trans-[3H]icosatetraenoic acid (leukotriene B4, LTB4) for 30 min at 37 degrees C in 10 mM potassium phosphate buffer (pH 7.5) with 100 microM NADPH and the 150,000 X g supernatant of sonicated human polymorphonuclear leukocytes (PMN). The reaction product exhibited the same mobility on reversed-phase HPLC (RP-HPLC) and TLC as standard 20-hydroxy-LTB4 (20-OH-LTB4). When the omega-oxidation product of [3H]LTB4 was eluted from a Sep-Pak, resolved by RP-HPLC, and analyzed by GC/MS, its structure was determined to be solely 20-OH-LTB4. The Km of the 20-hydroxylase for [3H]LTB4 at its optimal pH of 7.5 was 0.22 +/- 0.08 microM (mean +/- SD, n = 4) and the Vmax was 48 +/- 11 pmol/min X mg of protein (mean +/- SD, n = 4). When the concentration of [3H]LTB4 was fixed at 1.5 microM, the Km for NADPH was 1.01 +/- 0.59 microM (mean +/- SD, n = 3). The location in the 150,000 X g supernatant of the LTB4 20-hydroxylase distinguishes it from the cytochrome P-450 system of liver, lung, and kidney microsomes and from the NADPH oxidase-cytochrome b-245 system of the human PMN. The LTB4 20-hydroxylase is either a unique cytochrome P-450 or other monooxygenase. PMID:2986111

  12. Evaluation of human polymorphonuclear behavior on textured titanium and calcium-phosphate coated surfaces.

    PubMed

    Moura, Camilla C G; Machado, Juliana R; Silva, Marcos V; Rodrigues, Denise B R; Zanetta-Barbosa, Darceny; Jimbo, Ryo; Tovar, Nick; Coelho, Paulo G

    2013-06-01

    Few studies have evaluated the effects of titanium (Ti) surface modifications on polymorphonuclear neutrophils (PMNs). Human PMNs' viability and release of key mediators-such as IL1β, IL6, TNFα, IL12, IL10, IL4, TGFβ1, IL8, IP-10, and Mig-were evaluated on three different Ti surface treatments: (1) machined Ti; (2) alumina-blasted and acid-etched Ti (AB/AE); and (3) calcium phosphate coating of 300-500 nm by ion beam onto the AB/AE Ti surface (CaP). A polystyrene surface was used as a negative control. The PMNs were purified from whole human blood and cultured for 6 h. Cell viability was determined by flow cytometry, and the supernatant was evaluated to determine the levels of cytokines and chemokines. Results showed that the percentage of viable cells was significantly lower on the CaP surface compared to the control (p < 0.05) relative to the other groups. No differences in the levels of IL8, MIG, and IP10 were detected between groups. Significantly higher levels of IL1β (p = 0.046) and TNFα (p = 0.016) were detected for the CaP surfaces compared to AB/AE surface only. The levels of IL4, IL10, and TGFβ1 secreted from the PMNs in the CaP group were significantly lower than in the control and machined groups (p < 0.05) that were statistically comparable to AB/AE. Overall, the addition of a thin CaP coating to the AB/AE Ti surface influenced the secretion profile of pro-inflammatory cytokines due to the higher release of pro-inflammatory cytokines (IL1β and TNFα) on these surfaces. PMID:23598427

  13. Resistance of Capnocytophaga canimorsus to killing by human complement and polymorphonuclear leukocytes.

    PubMed

    Shin, Hwain; Mally, Manuela; Meyer, Salome; Fiechter, Chantal; Paroz, Cécile; Zaehringer, Ulrich; Cornelis, Guy R

    2009-06-01

    Capnocytophaga canimorsus is a bacterium of the canine oral flora known since 1976 to cause rare but severe septicemia and peripheral gangrene in patients that have been in contact with a dog. It was recently shown that these bacteria do not elicit an inflammatory response (H. Shin, M. Mally, M. Kuhn, C. Paroz, and G. R. Cornelis, J. Infect. Dis. 195:375-386, 2007). Here, we analyze their sensitivity to the innate immune system. Bacteria from the archetype strain Cc5 were highly resistant to killing by complement. There was little membrane attack complex (MAC) deposition in spite of C3b deposition. Cc5 bacteria were as resistant to phagocytosis by human polymorphonuclear leukocytes (PMNs) as Yersinia enterocolitica MRS40, endowed with an antiphagocytic type III secretion system. We isolated Y1C12, a transposon mutant that is hypersensitive to killing by complement via the antibody-dependent classical pathway. The mutation inactivated a putative glycosyltransferase gene, suggesting that the Y1C12 mutant was affected at the level of a capsular polysaccharide or lipopolysaccharide (LPS) structure. Cc5 appeared to have several polysaccharidic structures, one being altered in Y1C12. The structure missing in Y1C12 could be purified by classical LPS purification procedures and labeled by tritiated palmitate, indicating that it is more likely to be an LPS structure than a capsule. Y1C12 bacteria were also more sensitive to phagocytosis by PMNs than wild-type bacteria. In conclusion, a polysaccharide structure, likely an LPS, protects C. canimorsus from deposition of the complement MAC and from efficient phagocytosis by PMNs. PMID:19307219

  14. Resistance of Capnocytophaga canimorsus to Killing by Human Complement and Polymorphonuclear Leukocytes▿

    PubMed Central

    Shin, Hwain; Mally, Manuela; Meyer, Salome; Fiechter, Chantal; Paroz, Cécile; Zaehringer, Ulrich; Cornelis, Guy R.

    2009-01-01

    Capnocytophaga canimorsus is a bacterium of the canine oral flora known since 1976 to cause rare but severe septicemia and peripheral gangrene in patients that have been in contact with a dog. It was recently shown that these bacteria do not elicit an inflammatory response (H. Shin, M. Mally, M. Kuhn, C. Paroz, and G. R. Cornelis, J. Infect. Dis. 195:375-386, 2007). Here, we analyze their sensitivity to the innate immune system. Bacteria from the archetype strain Cc5 were highly resistant to killing by complement. There was little membrane attack complex (MAC) deposition in spite of C3b deposition. Cc5 bacteria were as resistant to phagocytosis by human polymorphonuclear leukocytes (PMNs) as Yersinia enterocolitica MRS40, endowed with an antiphagocytic type III secretion system. We isolated Y1C12, a transposon mutant that is hypersensitive to killing by complement via the antibody-dependent classical pathway. The mutation inactivated a putative glycosyltransferase gene, suggesting that the Y1C12 mutant was affected at the level of a capsular polysaccharide or lipopolysaccharide (LPS) structure. Cc5 appeared to have several polysaccharidic structures, one being altered in Y1C12. The structure missing in Y1C12 could be purified by classical LPS purification procedures and labeled by tritiated palmitate, indicating that it is more likely to be an LPS structure than a capsule. Y1C12 bacteria were also more sensitive to phagocytosis by PMNs than wild-type bacteria. In conclusion, a polysaccharide structure, likely an LPS, protects C. canimorsus from deposition of the complement MAC and from efficient phagocytosis by PMNs. PMID:19307219

  15. Cellular Uptake of Two Fluoroketolides, HMR 3562 and HMR 3787, by Human Polymorphonuclear Neutrophils In Vitro

    PubMed Central

    Abdelghaffar, H.; Vazifeh, D.; Labro, M. T.

    2001-01-01

    We analyzed the cellular accumulation of two new fluoroketolides, HMR 3562 and HMR 3787, by human polymorphonuclear neutrophils (PMN) in vitro. Both compounds were rapidly taken up by PMN, with a cellular-to-extracellular concentration ratio (C/E) of about 141 (HMR 3562) and 117 (HMR 3787) at 5 min, and this was followed by a plateau at 60 to 180 min, with a C/E of >300 at 180 min. Both ketolides were mainly located in PMN granules (about 75%) and egressed slowly from loaded cells (about 40% at 60 min), owing to avid reuptake. Uptake was moderately sensitive to external pH, and activation energy was also moderate (about 70 kJ/mol). As with other macrolides and ketolides, the existence of an active transport system was suggested by (i) the strong interindividual variability in uptake kinetics, suggesting variability in the number or activity of a transport protein; (ii) the saturation kinetics characteristic of a carrier-mediated transport system (Vmax, about 2,300 ng/2.5 × 106 PMN/5 min; Km, about 50 μg/ml); (iii) the inhibitory effects of Ni2+ (a blocker of the Na+-Ca2+ exchanger), phorbol myristate acetate (a protein kinase C activator), and H89 (a protein kinase A inhibitor). Although these two ketolides are more related to HMR 3647 (telithromycin), it is interesting that the presence of a fluoride gave these molecules a cellular pharmacokinetics more like those of HMR 3004 than those of HMR 3647. The macrolide transport system has not been yet elucidated, but our data confirm that, despite variations in chemical structure, all erythromycin A derivatives share a transmembrane transport system. PMID:11557472

  16. Release of PAF by human polymorphonuclear leucocytes stimulated by immune complexes bound to Sepharose particles and human erythrocytes.

    PubMed Central

    Virella, G; Lopes-Virella, M F; Shuler, C; Sherwood, T; Espinoza, G A; Winocour, P; Colwell, J A

    1983-01-01

    Human polymorphonuclear leucocytes (PMN) incubated with surface-bound immune complexes (IC) release a substance that induces platelet aggregation and serotonin-release. This substance was identified as platelet-activating factor (PAF) on the basis of its sensitivity to phospholipase A2 and of its purification by thin-layer chromatography in identical conditions to those used to purify zymosan-induced PAF. We used two types of substrates to absorb our IC:Sepharose particles to which we coupled human serum albumin, and which were later incubated with specific rabbit antiserum to form surface-bound immune complexes, and human erythrocytes, to which soluble IC can be passively adsorbed. Both types of surface-bound IC were found to stimulate the release of PAF by human PMN in the absence of complement. These results suggest that PMN may play a central role in the early stages of IC-induced inflammation: they recognize IC adsorbed to red cells or to any other cell able to adsorb IC, and they induce the activation of platelets and release of vasoactive amines, which leads to the increase of vascular permeability believed to be essential for extravascular IC deposition. PMID:6885111

  17. Stimulation of human polymorphonuclear leukocyte oxidative metabolism by type 1 pili from Escherichia coli.

    PubMed Central

    Goetz, M B; Silverblatt, F J

    1987-01-01

    We compared the degree to which Escherichia coli phase variants which do (T1P+ E. coli) or do not (T1P- E. coli) express type 1 pili (T1P) stimulate human polymorphonuclear leukocyte (PMN) oxidative activity. Unopsonized T1P+ E. coli stimulated the release of 0.20 to 0.24 nmol of H2O2 per 10(6) PMN per min and the consumption of 1.4 to 4.0 nmol of O2 per 10(6) PMN per min; no measurable PMN oxidative activity was stimulated by unopsonized T1P- E. coli. In the presence of serum opsonins, T1P+ E. coli stimulated the release of 1.12 to 1.16 nmol of H2O2 per 10(6) PMN per min and the consumption of 5.0 to 6.0 nmol of O2 per 10(6) PMN per min, whereas T1P- E. coli stimulated the release of 0.42 to 0.43 nmol of H2O2 per 10(6) PMN per min and the consumption of 0.6 to 2.0 nmol of O2 per 10(6) PMN per min. Although unaggregated T1P did not stimulate PMN, latex beads coated with T1P (T1P-latex) stimulated alpha-methylmannoside-inhibitable, opsonin-independent PMN oxidative activity. The activity stimulated by either T1P+ E. coli or T1P-latex was susceptible to inhibition by cytochalasin B. Latex particles coated with bovine serum albumin or mannose-resistant pili did not stimulate PMN. These data indicate that T1P+ E. coli stimulate PMN oxidative metabolism more effectively than do T1P- E. coli and that a similar PMN oxidative response follows cellular stimulation by either unopsonized T1P+ or opsonized T1P- E. coli. Furthermore, T1P-latex faithfully mimics the ability of T1P+ E. coli to stimulate PMN oxidative metabolism. Such particles may be useful in further analyses of cellular responses to T1P+ E. coli. Images PMID:2880806

  18. Hydrogen peroxide signals E. coli phagocytosis by human polymorphonuclear cells; up-stream and down-stream pathway.

    PubMed

    Petropoulos, Michalis; Karamolegkou, Georgia; Rosmaraki, Eleftheria; Tsakas, Sotiris

    2015-12-01

    Hydrogen peroxide (Η2Ο2) is produced during a variety of cellular procedures. In this paper, the regulatory role of Η2Ο2, in Escherichia coli phagocytosis by the human polymorphonuclears, was investigated. White blood cells were incubated with dihydrorhodamine (DHR) in order to study H2O2 synthesis and E. coli-FITC to study phagocytosis. Flow cytometry revealed increased synthesis of H2O2 in polymorphonuclears which incorporated E. coli-FITC. The blocking of H2O2 synthesis by specific inhibitors, N-ethylmaleimide (ΝΕΜ) for NADPH oxidase and diethyldithiocarbamate (DDC) for superoxide dismutase (SOD), decreased E. coli phagocytosis, as well. Immunoblot analysis of white blood cell protein extracts revealed that the blocking of NADPH oxidase and SOD decreased ERK-1/2 phosphorylation, while it had no effect on JNK and p38. Confocal microscopy showed that phosphorylation of MAPKs and phagocytosis solely occur in the polymorphonuclear and not in mononuclear cells. The use of specific MAPKs inhibitors showed that all of them are necessary for phagocytosis, but only phospho-p38 affects H2O2 synthesis. The blocking of JNK phosphorylation, in the presence of E. coli, evoked a further decrease of cytoplasmic p47 thus increasing its translocation onto the plasma membrane for the assembly of NADPH oxidase. It appears that newly synthesised H2O2 invigorates the phosphorylation and action of ERK-1/2 in E. coli phagocytosis, while phospho-JNK and phospho-p38 appear to regulate H2O2 production. PMID:26204503

  19. Bronchodilator and anti-inflammatory activities of glaucine: In vitro studies in human airway smooth muscle and polymorphonuclear leukocytes.

    PubMed

    Cortijo, J; Villagrasa, V; Pons, R; Berto, L; Martí-Cabrera, M; Martinez-Losa, M; Domenech, T; Beleta, J; Morcillo, E J

    1999-08-01

    1. Selective phosphodiesterase 4 (PDE4) inhibitors are of potential interest in the treatment of asthma. We examined the effects of the alkaloid S-(+)-glaucine, a PDE4 inhibitor, on human isolated bronchus and granulocyte function. 2. Glaucine selectively inhibited PDE4 from human bronchus and polymorphonuclear leukocytes (PMN) in a non-competitive manner (Ki=3.4 microM). Glaucine displaced [3H]-rolipram from its high-affinity binding sites in rat brain cortex membranes (IC50 approximately 100 microM). 3. Glaucine inhibited the spontaneous and histamine-induced tone in human isolated bronchus (pD2 approximately 4.5). Glaucine (10 microM) did not potentiate the isoprenaline-induced relaxation but augmented cyclic AMP accumulation by isoprenaline. The glaucine-induced relaxation was resistant to H-89, a protein kinase A inhibitor. Glaucine depressed the contractile responses to Ca2+ (pD'2 approximately 3.62) and reduced the sustained rise of [Ca2+]i produced by histamine in cultured human airway smooth muscle cells (-log IC50 approximately 4.3). 4. Glaucine augmented cyclic AMP levels in human polymorphonuclear leukocytes challenged with N-formyl-Met-Leu-Phe (FMLP) or isoprenaline, and inhibited FMLP-induced superoxide generation, elastase release, leukotriene B4 production, [Ca2+]i signal and platelet aggregation as well as opsonized zymosan-, phorbol myristate acetate-, and A23187-induced superoxide release. The inhibitory effect of glaucine on superoxide generation by FMLP was reduced by H-89. 5. In conclusion, Ca2+ channel antagonism by glaucine appears mainly responsible for the relaxant effect of glaucine in human isolated bronchus while PDE4 inhibition contributes to the inhibitory effects of glaucine in human granulocytes. The very low PDE4/binding site ratio found for glaucine makes this compound attractive for further structure-activity studies. PMID:10455321

  20. Bronchodilator and anti-inflammatory activities of glaucine: In vitro studies in human airway smooth muscle and polymorphonuclear leukocytes

    PubMed Central

    Cortijo, J; Villagrasa, V; Pons, R; Berto, L; Martí-Cabrera, M; Martinez-Losa, M; Domenech, T; Beleta, J; Morcillo, E J

    1999-01-01

    Selective phosphodiesterase 4 (PDE4) inhibitors are of potential interest in the treatment of asthma. We examined the effects of the alkaloid S-(+)-glaucine, a PDE4 inhibitor, on human isolated bronchus and granulocyte function.Glaucine selectively inhibited PDE4 from human bronchus and polymorphonuclear leukocytes (PMN) in a non-competitive manner (Ki=3.4 μM). Glaucine displaced [3H]-rolipram from its high-affinity binding sites in rat brain cortex membranes (IC50∼100 μM).Glaucine inhibited the spontaneous and histamine-induced tone in human isolated bronchus (pD2∼4.5). Glaucine (10 μM) did not potentiate the isoprenaline-induced relaxation but augmented cyclic AMP accumulation by isoprenaline. The glaucine-induced relaxation was resistant to H-89, a protein kinase A inhibitor. Glaucine depressed the contractile responses to Ca2+ (pD'2∼3.62) and reduced the sustained rise of [Ca2+]i produced by histamine in cultured human airway smooth muscle cells (−log IC50∼4.3).Glaucine augmented cyclic AMP levels in human polymorphonuclear leukocytes challenged with N-formyl-Met-Leu-Phe (FMLP) or isoprenaline, and inhibited FMLP-induced superoxide generation, elastase release, leukotriene B4 production, [Ca2+]i signal and platelet aggregation as well as opsonized zymosan-, phorbol myristate acetate-, and A23187-induced superoxide release. The inhibitory effect of glaucine on superoxide generation by FMLP was reduced by H-89.In conclusion, Ca2+ channel antagonism by glaucine appears mainly responsible for the relaxant effect of glaucine in human isolated bronchus while PDE4 inhibition contributes to the inhibitory effects of glaucine in human granulocytes. The very low PDE4/binding site ratio found for glaucine makes this compound attractive for further structure-activity studies. PMID:10455321

  1. Factors influencing human leukocyte adherence in vitro.

    PubMed

    Stepniewicz, W; Tchórzewski, H; Luciak, M

    1983-01-01

    Studies were performed on factors influencing leucocyte adherence in vitro. Blood condensation was found to increase leukocyte adherence. Addition of heparin, dextran or ethanol caused a significant reduction of white blood cell count in blood samples in comparison with blood mixed with sodium EDTA or ACD solution. This suggests the existence of two granulocyte subpopulations; viz, rapidly adhering and slowly adhering. Heparin enhanced granulocyte adherence, while dextran and ethanol decreased it. Five-day storage of ACD blood led to a decrease in granulocyte adherence, while addition of heparin or histamine to ACD blood prevented this change to occur. The glucose concentration of 1,000 mg/dl augmented granulocyte adherence, while higher glucose concentrations induced its progressive fall below the control values. There was no significant change of lymphocyte adherence during the experiments. PMID:6194070

  2. Effects of SCA40 on human isolated bronchus and human polymorphonuclear leukocytes: comparison with rolipram, SKF94120 and levcromakalim.

    PubMed Central

    Cortijo, J.; Villagrasa, V.; Navarrete, C.; Sanz, C.; Berto, L.; Michel, A.; Bonnet, P. A.; Morcillo, E. J.

    1996-01-01

    1. SCA40 (0.1 nM-0.1 mM) produced concentration-dependent suppression of the spontaneous tone of human isolated bronchus (-log EC50 = 6.85 +/- 0.09; n = 10) and reached a maximal relaxation similar to that of theophylline (3 mM). The potency (-log EC50 values) of SCA40 compared to other relaxants was rolipram (7.44 +/- 0.12; n = 9) > SCA40 > or = levcromakalim (6.49 +/- 0.04; n = 6) > SKF94120 (5.87 +/- 0.10; n = 9). 2. When tested against the activity of the isoenzymes of cyclic nucleotide phosphodiesterase (PDE) isolated from human bronchus, SCA40 proved highly potent against PDE III (-log IC50 = 6.47 +/- 0.16; n = 4). It was markedly less potent against PDE IV (4.82 +/- 0.18; n = 4) and PDE V (4.32 +/- 0.11; n = 4). 3. Human polymorphonuclear leukocytes (PMNs) stimulated with N-formylmethionyl-leucyl-phenylalanine (FMLP) produced a concentration-dependent superoxide anion generation and elastase release. SCA40 (1 nM-10 microM) produced a concentration-related inhibition of FMLP (30 nM approximately EC50)-induced superoxide production (-log IC50 = 5.48 +/- 0.10; n = 6) and elastase release (-log IC50 = 5.50 +/- 0.26; n = 6). Rolipram was an effective inhibitor of superoxide generation and elastase release (-log IC50 values approximately 8) while SKF94120 and levcromakalim were scarcely effective. 4. FMLP (30 nM) and thimerosal (20 microM) induced leukotriene B4 production and elevation of intracellular calcium concentration in human PMNs. The production of leukotriene B4 was inhibited by SCA40 in a concentration-related manner (-log IC50 = 5.94 +/- 0.22; n = 6) but SCA40 was less effective against the elevation of intracellular calcium. Rolipram was an effective inhibitor of leukotriene B4 synthesis (-log IC50 approximately 7) and intracellular calcium elevation (-log IC50 approximately 6) while SKF94120 and levcromakalim were scarcely effective. 5. It is concluded that SCA40 is an effective inhibitor of the inherent tone of human isolated bronchus. The

  3. Inhibition of PAF synthesis by stimulated human polymorphonuclear leucocytes with cloricromene, an inhibitor of phospholipase A2 activation.

    PubMed Central

    Ribaldi, E.; Mezzasoma, A. M.; Francescangeli, E.; Prosdocimi, M.; Nenci, G. G.; Goracci, G.; Gresele, P.

    1996-01-01

    1. A phospholipase A2 (PLA2) represents the key enzyme in the remodelling pathway of platelet-activating factor (PAF) synthesis in human polymorphonuclear (PMN) leucocytes. 2. PLA2 activation is also the rate-limiting step for the release of the arachidonic acid utilized for the synthesis of leukotrienes in stimulated leucocytes; however, it is unknown whether the PLA2s involved in the two biosynthetic pathways are identical. 3. Cloricromene (8-monochloro-3-beta-diethylaminoethyl-4-methyl-7-ethoxy- carbonylmethoxy coumarin) is an antithrombotic coumarin derivative which inhibits platelet and leucocyte function and suppresses arachidonic acid liberation by interfering with PLA2 activation. 4. The aim of the present study was to assess whether chloricromene inhibits PAF synthesis by stimulated human polymorphonuclear leucocytes (PMNs). 5. Cloricromene (50-500 microM) inhibited in a concentration-dependent manner the release of PAF, as measured by h.p.l.c. bioassay, from A23187-stimulated PMNs. Significant inhibition (45%) of PAF-release was obtained with 50 microM cloricromene and the IC50 was 85 microM. Mepacrine (500 microM), a non-specific PLA2 inhibitor, strikingly reduced PAF release. 6. The incorporation of [3H]-acetate into [3H]-PAF induced by serum-treated zymosan in human PMNs was also inhibited concentration-dependently by cloricromene, with an IC50 of 105 microM. Mepacrine also suppressed [3H]-acetate incorporation into [3H]-PAF. 7. Cloricromene did not affect the activities of the enzymes involved in PAF-synthesis acetyltransferase or phosphocholine transferase. 8. Our data demonstrate that cloricromene, an inhibitor of PLA2-activation in human leucocytes, reduces the synthesis of PAF by stimulated PMNs. This finding has a twofold implication: the PLA2s (or the mechanisms that regulate their activation) involved in PAF synthesis and arachidonate release in human leucocytes are either identical or else indistinguishable by their sensitivity to cloricromene

  4. CD44 is a cytotoxic triggering molecule on human polymorphonuclear cells.

    PubMed

    Pericle, F; Sconocchia, G; Titus, J A; Segal, D M

    1996-11-15

    In this study, we present evidence that CD44 is a cytotoxic triggering molecule on freshly isolated polymorphonuclear cells (PMN). PMN constitutively express high levels of CD44 as determined by FACS analysis, and immunoprecipitation studies using PMN lysates and an anti-CD44 mAb show a band of 80 to 90 kDa that migrates slightly faster than CD44 from PBL. A bispecific Ab consisting of anti-CD44 Fab cross-linked to anti-DNP Fab (anti-CD44(Fab) x anti-DNP(Fab)) induces PMN to lyse DNP-coated tumor cells in an 18-h assay, and this lysis is specifically inhibited by a polyclonal anti-CD44 F(ab')2. A second bispecific Ab, anti-CD16(Fab) x anti-DNP(Fab), that binds to Fc(gamma)RIIIb on PMN does not induce lysis, indicating that the bridging of target cells to PMN per se is not sufficient for killing. Moreover, CD44-directed killing by PMN results in the lysis of bystander cells, suggesting that the mechanisms of tumor cytolysis by CD44-targeted PMN does not require cell-cell contact. Lastly, PMN lyse target cells coated with hyaluronic acid (HA), the principal ligand for CD44, and this cytolytic activity is specifically blocked by the polyclonal anti-CD44 F(ab')2 and by an anti-CD44 mAb. We suggest that the interaction of HA with CD44 on neutrophils might initiate cytotoxic or inflammatory responses in vivo when neutrophils encounter high amounts of HA, for example on tumor cells, or in the extracellular matrix. PMID:8906846

  5. Effects of naftifine and terbinafine, two allylamine antifungal drugs, on selected functions of human polymorphonuclear leukocytes.

    PubMed Central

    Vago, T; Baldi, G; Colombo, D; Barbareschi, M; Norbiato, G; Dallegri, F; Bevilacqua, M

    1994-01-01

    Many antimycotic agents negatively affect the natural immune response. Typically, these drugs impair polymorphonuclear leukocyte (PMN) production of superoxide anion, chemotaxis, or the killing of pathogens. Allylamines are a new class of antimycotic compounds with a new mechanism of antifungal action, i.e., inhibition of the fungal squalene epoxidase. The trial that we describe aimed to evaluate the effects of two allylamines, terbinafine and naftifine, on selected functions of PMNs, i.e., superoxide anion production, chemotaxis, and killing of Candida albicans blastospores. Terbinafine and naftifine on their own did not affect superoxide anion production when they were added to PMNs. When PMNs were preincubated with allylamines and were then stimulated by N-formyl-Met-Leu-Phe or phorbol 12-myristate 13-acetate, superoxide anion production was increased (priming effect). Since intracellular free calcium (Ca2+i) is involved in the control of superoxide anion production, we evaluated the effects of the allylamines on the Ca2+i concentration ([Ca2+]i). In the presence of terbinafine or naftifine, the [Ca2+]i increased in a dose-dependent manner; the source of Ca2+i was not extracellular since it was not affected by extracellular calcium chelation with ethylene glycol-bis(beta-aminoethyl ether)-N,N,N',N'-tetraacetic acid. In the presence of terbinafine or naftifine, chemotaxis of PMNs was not impaired. Terbinafine and naftifine slightly but significantly increased the killing of C. albicans blastospores (P < 0.05 at 10 and 100 microM). In conclusion, in contrast to imidazole-like drugs, the allylamine antimycotic compounds terbinafine and naftifine enhance selected functions of PMNs. PMID:7872755

  6. Tumorigenic conversion of a rat urothelial cell line by human polymorphonuclear leukocytes activated by lipopolysaccharide.

    PubMed

    Tamatani, T; Turk, P; Weitzman, S; Oyasu, R

    1999-08-01

    Chronic inflammation is a significant risk factor for the development of urinary bladder cancer. We have shown that inflammation induced by killed Escherichia coli and also by its lipopolysaccharide (LPS) strikingly enhances N-methyl-N-nitrosourea (MNU)-initiated rat bladder carcinogenesis. Aspirates from the bladder lumen contained a large quantity of hydrogen peroxide (H2O2) and several cytokines. In this study, we tested the hypothesis that reactive oxygen intermediates (ROI) released from activated polymorphonuclear leukocytes (PMN) are involved in inflammation-associated bladder carcinogenesis. Using an immortalized nontumorigenic rat urothelial cell line, MYP3, we examined the effect of LPS-activated PMN on malignant transformation. MYP3 cells pretreated with or without MNU were exposed daily to LPS-activated PMN for one week and were then tested for growth in soft agar. In contrast to no colony formation by the parental cells, a varying number of colonies developed from cells treated with LPS-activated PMN. Although combined treatment with MNU and PMN was most effective (P<0.01), cells treated with LPS-activated PMN alone also formed a small number of colonies. Addition of catalase, which decomposes H2O2, and/or an antioxidant, alpha-tocopherol, reduced the number of colonies induced by LPS-activated PMN (P<0.05). Cells derived from colonies were tumorigenic in athymic nude mice. However, tumorigenicity in mice was greater with cells treated with both MNU and PMN than with cells treated with PMN alone. Our results suggest that ROI released from LPS-activated PMN may be one of the mechanisms involved in the carcinogenesis associated with active urinary tract infection. PMID:10543254

  7. A Novel Murine Anti-Lactoferrin Monoclonal Antibody Activates Human Polymorphonuclear Leukocytes through Membrane-Bound Lactoferrin and TLR4

    PubMed Central

    Hu, Xiao-Min; Xu, Yan-Rui; Yan, Ru; Sun, Shu-Liang; Dong, Hong-Liang; Wang, Jun; Gao, Xiao-Ming

    2015-01-01

    Soluble lactoferrin (LTF) is a versatile molecule that not only regulates the iron homeostasis, but also harbors direct microbicidal and immunomodulating abilities in mammalian body fluids. In contrast, little is known about the function of membrane-bound LTF (mbLTF), although its expression on human polymorphonuclear leukocytes (huPMNs) has been reported for decades. Given that LTF/anti-LTF antibodies represent a potential diagnostic/prognostic biomarker and a therapeutic target in patients with immune disorders, we wished, in the present study, to generate a novel human LTF- (huLTF-) specific mAb suitable for detailed analyses on the expression and function of mbLTF as well as for deciphering the underlying mechanisms. By using the traditional hybridoma cell fusion technology, we obtained a murine IgG1 (kappa) mAb, M-860, against huLTF. M-860 recognizes a conformational epitope of huLTF as it binds to natural, but not denatured, huLTF in ELISA. Moreover, M-860 detects mbLTF by FACS and captures endogenous huLTF in total cell lysates of huPMNs. Functionally, M-860 induces the activation of huPMNs partially through TLR4 but independently of phagocytosis. M-860 is thus a powerful tool to analyze the expression and function of human mbLTF, which will further our understanding of the roles of LTF in health and disease. PMID:26649297

  8. Granulocyte colony-stimulating factor does not enhance phagocytosis or microbicidal activity of human mature polymorphonuclear neutrophils in vitro.

    PubMed Central

    Shimono, N; Okada, K; Takeda, D; Eguchi, K; Misumi, H; Sawae, Y; Niho, Y

    1994-01-01

    The direct effects of human granulocyte colony-stimulating factor (hG-CSF) on mature polymorphonuclear neutrophils (PMNs) in vitro were studied with regard to chemotaxis, superoxide production, and phagocytosis and microbicidal activity against the following viable microorganisms: Staphylococcus aureus, serum-resistant Pseudomonas aeruginosa, and Candida albicans. Recombinant hG-CSF (rhG-CSF) acted as a chemoattractant for human PMNs in a dose-dependent manner. The chemotactic response of PMNs to N-formyl-methionyl-leucyl-phenylalanine (FMLP) was not enhanced by rhG-CSF at any of the concentrations used. rhG-CSF did not induce the generation of superoxide by itself. However, rhG-CSF was able to prime human PMNs and to enhance O2- release stimulated by FMLP in a dose-dependent manner. rhg-CSF did not enhance phagocytosis or killing of the three species of microorganisms by normal PMNs. With PMNs obtained from patients who had hematological disorders or solid tumors, no enhancement of the microbicidal activity was observed in most cases. Microbial killing mediated by PMNs depended on the ratio of PMNs to target organisms. We concluded from these facts that the most important effect of rhG-CSF was to increase the number of the peripheral PMNs and not to enhance the functions of mature PMNs. PMID:8556501

  9. Effect of human polymorphonuclear and mononuclear leukocytes on chromosomal and plasmid DNA of Escherichia coli. Role of acid DNase

    SciTech Connect

    Rozenberg-Arska, M.; van Strijp, J.A.; Hoekstra, W.P.; Verhoef, J.

    1984-05-01

    Phagocytosis and killing by polymorphonuclear and mononuclear leukocytes are important host resistance factors against invading microorganisms. Evidence showing that killing is rapidly followed by degradation of bacterial components is limited. Therefore, we studied the fate of Escherichia coli DNA following phagocytosis of E. coli by polymorphonuclear and mononuclear leukocytes. (/sup 3/H)Thymidine-labeled, unencapsulated E. coli PC2166 and E. coli 048K1 were incubated in serum, washed, and added to leukocytes. Uptake and killing of the bacteria and degradation of DNA were measured. Although phagocytosis and killing by mononuclear leukocytes was less efficient than that by polymorphonuclear leukocytes, only mononuclear leukocytes were able to degrade E. coli PC2166 DNA. Within 2 h, 60% of the radioactivity added to mononuclear leukocytes was released into the supernate, of which 40% was acid soluble. DNA of E. coli 048K1 was not degraded. To further analyze the capacity of mononuclear leukocytes to degrade E. coli DNA, chromosomal and plasmid DNA was isolated from ingested bacteria and subjected to agarose gel-electrophoresis. Only chromosomal DNA was degraded after phagocytosis. Plasmid DNA of E. coli carrying a gene coding for ampicillin resistance remained intact for a 2-h period after ingestion, and was still able to transform recipient E. coli cells after this period. Although we observed no DNA degradation during phagocytosis by polymorphonuclear leukocytes, lysates of both polymorphonuclear and mononuclear leukocytes contained acid-DNase activity with a pH optimum of 4.9. However, the DNase activity of mononuclear leukocytes was 20 times higher than that of polymorphonuclear leukocytes. No difference was observed between DNase activity from polymorphonuclear and mononuclear leukocytes from a chronic granulomatous disease patient with DNase activity from control polymorphonuclear and mononuclear leukocytes.

  10. Role of the Yersinia YopJ protein in suppressing interleukin-8 secretion by human polymorphonuclear leukocytes.

    PubMed

    Spinner, Justin L; Hasenkrug, Aaron M; Shannon, Jeffrey G; Kobayashi, Scott D; Hinnebusch, B Joseph

    2016-01-01

    Polymorphonuclear leukocytes, in addition to their direct bactericidal activities, produce cytokines involved in the activation and regulation of the innate and adaptive immune response to infection. In this study we evaluated the cytokine response of human PMNs following incubation with the pathogenic Yersinia species. Yersinia pestis strains with the pCD1 virulence plasmid, which encodes cytotoxic Yop proteins that are translocated into host cells, stimulated little or no cytokine production compared to pCD1-negative strains. In particular, PMNs incubated with pCD1-negative Y. pestis secreted 1000-fold higher levels of interleukin-8 (IL-8 or CXCL8), a proinflammatory chemokine important for PMN recruitment and activation. Deletion of yopE, -H, -T, -M or ypkA had no effect on pCD1-dependent inhibition, whereas deletion of yopJ resulted in significantly increased IL-8 production. Like Y. pestis, the enteropathogenic Yersinia species inhibited IL-8 secretion by PMNs, and strains lacking the virulence plasmid induced high levels of IL-8. Our results show that virulence plasmid-encoded effector Yops, particularly YopJ, prevent IL-8 secretion by human PMNs. Suppression of the chemotactic IL-8 response by Y. pestis may contribute to the delayed PMN recruitment to the infected lymph node that typifies bubonic plague. PMID:26361732

  11. beta. -Endorphin and related peptides suppress phorbol myristate acetate-induced respiratory burst in human polymorphonuclear leukocytes

    SciTech Connect

    Diamant, M.; Henricks, P.A.J.; Nijkamp, F.P.; de Wied, D. )

    1989-01-01

    In the present study, the immunomodulatory effect of {beta}-endorphin ({beta}-E) and shorter pro-opiomelancortin (POMC) fragments was evaluated by assessing their influence on respiratory burst in human polymorphonuclear leukocytes (PMN). The effect of the peptides on phorbol myristate acetate (PMA)-stimulated production of reactive oxygen metabolites was measured in a lucigenin-enhanced chemiluminescence (CL) assay. Both POMC peptides with opiate-like activity and their non-opioid derivatives were tested. With the exception of {alpha}-E, PMA-stimulated respiratory burst was suppressed by all POMC fragments tested. A U-shaped dose-response relation was observed. Doses lower than 10{sup {minus}17}M and higher than 10{sup {minus}8}M were without effect. {beta}-E and dT{beta}E both suppressed PMA-induced oxidative burst in human PMN at physiological concentrations. {gamma}-E and dT{gamma}E proved to be less potent inhibitors, reaching maximal effect at higher concentrations. DE{gamma}E exerted an even less pronounced but still significant suppressive effect at the concentration of 10{sup {minus}10}M. None of the endorphins tested was shown to affect resting oxidative metabolism in the PMN. The modulatory effects of the opioid peptides could not be blocked by the opioid antagonist naloxone.

  12. Effect of trans-resveratrol, a natural polyphenolic compound, on human polymorphonuclear leukocyte function

    PubMed Central

    Rotondo, Serenella; Rajtar, Grazyna; Manarini, Stefano; Celardo, Antonio; Rotilio, Domenico; de Gaetano, Giovanni; Evangelista, Virgilio; Cerletti, Chiara

    1998-01-01

    Polymorphonuclear leukocytes (PMN) may contribute to the pathogenesis of acute coronary heart disease (CHD).Epidemiological and laboratory evidence suggests that red wine, by virtue of its polyphenolic constituents, may be more effective than other alcoholic beverages in reducing the risk of CHD mortality.The aim of the present study was to investigate the effects of trans-resveratrol (3,4′,5-trihydroxy-trans-stilbene), a polyphenol present in most red wines, on functional and biochemical responses of PMN, upon in vitro activation.trans-Resveratrol exerted a strong inhibitory effect on reactive oxygen species produced by PMN stimulated with 1 μM formyl methionyl leucyl phenylalamine (fMLP) (IC50 1.3±0.13 μM, mean±s.e.mean), as evaluated by luminol-amplified chemiluminescence.trans-Resveratrol prevented the release of elastase and β-glucuronidase by PMN stimulated with the receptor agonists fMLP (1 μM, IC50 18.4±1.8 and 31±1.8 μM), and C5a (0.1 μM, IC50 41.6±3.5 and 42±8.3 μM), and also inhibited elastase and β-glucuronidase secretion (IC50 37.7±7 and 25.4±2.2 μM) and production of 5-lipoxygenase metabolites leukotriene B4 (LTB4), 6-trans-LTB4 and 12-trans-epi-LTB4 (IC50 48±7 μM) by PMN stimulated with the calcium ionophore A23187 (5 μM).trans-Resveratrol significantly reduced the expression and activation of the β2 integrin MAC-1 on PMN surface following stimulation, as revealed by FACS analysis of the binding of an anti-MAC-1 monoclonal antibody (MoAb) and of the CBRM1/5 MoAb, recognizing an activation-dependent epitope on MAC-1. Consistently, PMN homotypic aggregation and formation of mixed cell-conjugates between PMN and thrombin-stimulated fixed platelets in a dynamic system were also prevented by trans-resveratrol.These results, indicating that trans-resveratrol interferes with the release of inflammatory mediators by activated PMN and down-regulates adhesion-dependent thrombogenic PMN functions, may provide some

  13. Purification of the active C5a receptor from human polymorphonuclear leukocytes as a receptor - G sub i complex

    SciTech Connect

    Rollins, T.E.; Siciliano, S.; Kobayashi, S.; Cianciarulo, D.N.; Bonilla-Argudo, V.; Collier, K.; Springer, M.S. )

    1991-02-01

    The authors have isolated, in an active state, the C5a receptor from human polymorphonuclear leukocytes. The purification was achieved in a single step using a C5a affinity column in which the C5a molecule was coupled to the resin through its N terminus. The purified receptor, like the crude solubilized molecule, exhibited a single class of high-affinity binding sites with a K{sub d} of 30 pM. Further, the binding of C5a retained its sensitivity to guanine nucleotides, implying that the purified receptor contained a guanine nucleotide-binding protein (G protein). SDS/PAGE revealed the presence of three polypeptides with molecular masses of 42, 40, and 36 kDa, which were determined to be the C5a-binding subunit and the {alpha} and {beta} subunits of G{sub i}, respectively. The 36- and 40-kDa polypeptides were identified by immunoblotting and by the ability of pertussis toxin to ADP-ribosylate the 40-kDa molecule. These results confirm their earlier hypothesis that the receptor exists as a complex with a G protein in the presence or absence of C5a. The tight coupling between the receptor and G protein should make possible the identification of the G protein(s) involved in the transduction pathways used by C5a to produce its many biological effects.

  14. Potentiation of human polymorphonuclear leukocytes respiratory burst and phagocytosis by a standardized liver and spleen fraction of peptides.

    PubMed

    Cramer, R; Dri, P; Spessotto, P; Mittenzwei, H; Patriarca, P

    1993-06-01

    The effect of Factor AF2 (AF2), a xenogeneic fraction of peptides with a molecular weight of < 10,000 Dalton obtained from livers and spleens of newborn lambs, on the oxygen consumption and the phagocytic activity of human polymorphonuclear leukocytes (PMN) was studied. AF2 increased the oxygen uptake of PMN exposed both to serum-treated zymosan (STZ), a phagocytosable stimulus, and phorbol-myristate-acetate (PMA), a soluble stimulus. The potentiating effect of the drug was dose-dependent and more pronounced when suboptimal amounts of either stimulus were used. The phagocytic activity of PMN, as measured by the rate of mineral oil particles ingestion, was also increased by AF2 in a dose-dependent manner. These results suggest that the drug may influence PMN behaviour in at least two ways: 1. by increasing the rate of phagocytosis, and 2. by potentiating the respiratory burst induced by soluble and particulate stimuli. The results are discussed in relation to the beneficial effects of AF2 in cancer patients under chemotherapy or radiation treatment. PMID:8352824

  15. Poly(ethylene glycol)-containing hydrogels promote the release of primary granules from human blood-derived polymorphonuclear leukocytes

    PubMed Central

    Cohen, Hannah Caitlin; Lieberthal, Tyler Jacob; Kao, W. John

    2014-01-01

    Polymorphonuclear leukocytes (PMNs) are recruited to sites of injury and biomaterial implants. Once activated, PMNs can exocytose their granule subsets to recruit monocytes (MCs) and mediate MC/macrophage activation. We investigated the release of myeloperoxidase (MPO), a primary granule marker, and matrix metalloproteinase-9 (MMP-9), a tertiary granule marker, from human blood-derived PMNs cultured on poly(ethylene glycol) (PEG) hydrogels, polydimethylsiloxane (PDMS), tissue culture polystyrene (TCPS) and gelatin-PEG (GP) hydrogels, with and without the presence of the bacterial peptide formyl-Met-Leu-Phe. Supernatants from PMN cultures on PEG-containing hydrogels (i.e., PEG and GP hydrogels) had higher concentrations of MPO than those from PMN cultures on PDMS or TCPS at 2 hours. PMNs on all biomaterials released comparable levels of MMP-9 at 2 hours, indicating that PMNs cultured on PEG-containing hydrogels have different mechanisms of release for primary and tertiary granules. Src family kinases were involved in the release of MPO from PMNs cultured on PEG hydrogels, TCPS and GP hydrogels and in the release of MMP-9 from PMNs cultured on all four materials. The increased release of primary granules from PMNs on PEG-containing hydrogels did not significantly increase MC chemotaxis, indicating that additional co-effectors in the dynamic inflammatory milieu in vivo modulate PMN-mediated MC recruitment. PMID:24497370

  16. Human monocyte adherence measured by the nylon fibre microcolumn technique.

    PubMed

    Kelly, M K; Thong, Y H

    1984-11-30

    A simple rapid method for the measurement of human monocyte adherence using nylon fibre microcolumns is described. The kinetics indicate the optimal contact time to be 30 min for monocytes, compared with 10 min for neutrophils. The optimal temperature is 37 degrees C; significantly low values were obtained for 4 degrees C and 45 degrees C, while intermediate values were obtained for 25 degrees C. Monocyte adherence was more sensitive to inhibition by fluoride than cyanide, suggesting that energy for adherence is mainly derived from the glycolytic pathway. The addition of phorbol myristate acetate enhances monocyte adherence. Significant decay in monocyte adherence occurred after isolation from whole blood for 24 h or longer. PMID:6501891

  17. Adherence of Bilophila wadsworthia to cultured human embryonic intestinal cells.

    PubMed

    Gerardo, S H; Garcia, M M; Wexler, H M; Finegold, S M

    1998-02-01

    Adherence of Bilophila wadsworthia to the cultured human embryonic intestinal cell line, Intestine 407 (Int 407), varied among the strains tested from strongly adherent (76-100% cells positive for one or more adherent bacteria) to non- or weakly adherent (0-25% positive cells). Although negative staining revealed that infrequent cells of an adherent strain, WAL 9077, the adherent type-strain, WAL 7959, and a non-adherent strain, WAL 8448, expressed loosely associated fimbrial structures, a role for these structures in adhesion could not be confirmed with either scanning or thin-section electron micrography. Ruthenium red staining of thin-section preparations and subsequent electron microscopy failed to reveal an extensive extracellular polysaccharide layer. SDS-PAGE analysis of crude outer membrane fractions of WAL 9077 and WAL 8448 demonstrated clear differences in their major and minor outer membrane protein components. Thus, we postulate that the adherence of B. wadsworthia to Int 407 cells is mediated by an outer membrane or cell wall component. PMID:16887620

  18. Modulation of human neutrophil polymorphonuclear leucocyte migration by human plasma alpha-globulin inhibitors and synthetic esterase inhibitors.

    PubMed Central

    Goetzl, E J

    1975-01-01

    The exposure of isolated washed human neutrophils to purified human alpha1-antitrypsin resulted in a transient 2-fold enhancement of random migration and concomitant 70-90 per cent inhibition of chemotactic responsiveness to C5a or C3a, while treatment with alpha2-macroglobulin gave a less pronounced brief enhancement of random migration and prolonged 40-60 per cent suppression of chemotaxis. Peak effects occurred with concentrations of 1 mug/ml of alpha1-antitrypsin and 10 mug/ml of alpha2-macroglobulin. In contrast, the inhibitor of the activated first component of complement, at the highest concentration studied of 100/mug/ml, slightly enhanced chemotactic migration in response to C5a without influencing random migration. Preincubation of neutrophils with either L-1-tosylamide-2-phenylethyl-chloromethyl ketone (TPCK) or N-alpha-p-tosyl-L-lysine-chloromethyl ketone (TLCK) at concentrations of 10-8-10-4M suppressed chemotaxis with concomitant inhibition of random migration by TPCK and enhancement of random migration by TLCK. All agents worked directly and irreversibly on the cells but caused only slight stimulation of the activity of the hexose monophosphate shunt of layers of adherent neutrophils. The results suggest that interaction of the plasma alpha-globulins or synthetic esterase inhibitors with surface receptors on neutrophils can influence both the random migration and responsiveness to chemotactic factors of these cells. PMID:49293

  19. Carcinogenic sulfide salts of nickel and cadmium induce H2O2 formation by human polymorphonuclear leukocytes.

    PubMed

    Zhong, Z J; Troll, W; Koenig, K L; Frenkel, K

    1990-12-01

    Some derivatives of nickel, cadmium, and cobalt are carcinogenic in humans and/or animals but their mechanisms of action are not known. We show that they are capable of stimulating human polymorphonuclear leukocytes (PMNs), as measured by H2O2 formation, a known tumor promoter. Most effective were the carcinogens nickel subsulfide, which caused a 550% net increase in H2O2 over that formed by resting PMNs, followed by cadmium sulfide, 400%, and nickel disulfide, 200%. Nickel sulfide and cobalt sulfide caused statistically nonsignificant increases of 45 and 20%, respectively. Noncarcinogenic barium and manganese sulfides, and sulfates of nickel, cadmium, and cobalt were inactive. The enhancement of H2O2 formation by CdS and Ni3S2 (1 mumol/2.5 x 10(5) PMNs) was comparable to that mediated by the potent tumor promoter 12-O-tetradecanoylphorbol-13-acetate, used at 0.5 and 1 nM, respectively. Concurrent treatment of 12-O-tetradecanoylphorbol-13-acetate-stimulated PMNs with Ni3S2 or NiS caused a decrease in H2O2 accumulation from that expected if the effects were additive. Including catalase in the reaction mixture proved that the oxidant formed by stimulated PMNs was H2O2, whereas adding superoxide dismutase showed that superoxide was also present in PMN samples treated with NiS but not with Ni3S2. Since nickel- and cadmium-containing particulates are deposited in the lungs and cause infiltration of PMNs, the ability to activate those cells and induce H2O2 formation may contribute to their carcinogenicity. PMID:2253206

  20. Enhancement by clofazimine and inhibition by dapsone of production of prostaglandin E2 by human polymorphonuclear leukocytes in vitro.

    PubMed Central

    Anderson, R

    1985-01-01

    The effects of the antileprosy agents clofazimine and dapsone (1 to 10 micrograms/ml) on the spontaneous and stimulated release of prostaglandin E2 (PG E2) by human polymorphonuclear leukocytes (PMNL) in vitro have been investigated. PMNL were obtained from normal adult volunteers and three patients with leprosy (two borderline lepromatous and one subpolar lepromatous leprosy). The synthetic chemotactic tripeptide N-formyl-L-methionyl-L-leucyl-L-phenylalanine (FMLP) at a concentration of 10(-7) M was used as the stimulant of PG E2 synthesis. None of the test agents at the concentrations used inhibited the binding of radiolabeled FMLP to PMNL. However, dapsone at 5 and 10 micrograms/ml inhibited the spontaneous and FMLP-induced release of PG E2 by PMNL. Clofazimine, on the other hand, significantly increased both the spontaneous and the FMLP-induced synthesis of PG E2 by PMNL. The enhancing effects of clofazimine on FMLP-mediated synthesis of PG E2 were particularly striking and were observed at concentrations of 1 to 10 micrograms of the drug per ml. Measurements of PMNL spontaneous and FMLP-induced synthesis of PG E2 in the presence of both clofazimine and dapsone (5 micrograms/ml) indicated that the two drugs are mutually antagonistic. PMNL from both normal control subjects and patients with leprosy were equally sensitive to these effects of clofazimine and dapsone. The immunostimulatory and immunosuppressive properties of dapsone and clofazimine, respectively, may be related to the opposite effects of these agents on PG E2 synthesis in human leukocytes. PMID:3857019

  1. Major histocompatibility complex class II (DR) antigen and costimulatory molecules on in vitro and in vivo activated human polymorphonuclear neutrophils

    PubMed Central

    Sandilands, Gavin P; McCrae, Jame; Hill, Kathryn; Perry, Martin; Baxter, Derek

    2006-01-01

    We have previously shown that normal human peripheral blood polymorphonuclear neutrophils (PMNs) contain cytoplasmic ‘stores’ of three key molecules normally associated with antigen presentation and T-cell costimulation, i.e. major histocompatibility complex class II (DR) antigen, CD80 (B7-1) and CD86 (B7-2). These cytoplasmic molecules were found to translocate to the cell surface within a few minutes following cross-linking (X-L) of Mac-1: an early neutrophil activation signal. In this study we have compared X-L of Mac −1 in parallel with four other well documented in vitro neutrophil activators: phorbol myristate acetate, N-formyl methionyl leucyl phenylalanine, lipopolysaccharide, and phagocytosis of immunoglobulin G–Latex particles. In addition, we have used paired samples of neutrophils obtained from peripheral blood (as a control) and synovial fluid from patients with rheumatoid arthritis as a source of in vivo activated cells. With the exception of phagocytosis, all activators resulted in the rapid (within 30 min) generation of two populations of activated neutrophils (designated P1 and P2) based on flow-cytometry measurements of size, granularity and phenotype. Significant up-regulation of DR and costimulatory molecules was observed, predominantly on P2 cells, with all activators except phagocytosis. CD80 and CD86 were noted to respond to the various activation signals in a different pattern suggesting that their intracellular granule location may be different. Dual-staining confocal laser microscopy studies showed that CD80 is largely confined to secretory vesicles (SVs) while CD86 appears to have a much wider distribution being found in SVs and within secondary (specific) and primary (azurophilic) granules. Increased surface expression of these antigens was also observed on P2 synovial fluid neutrophils appearing as large heterogeneous clusters on the cell surface when visualized by confocal laser microscopy. PMID:17034427

  2. Modulation of leukotriene release from human polymorphonuclear leucocytes by PMA and arachidonic acid.

    PubMed Central

    Raulf, M; König, W

    1988-01-01

    Stimulation of human neutrophils (PMN) with Ca ionophore A23187, opsonized zymosan and formyl-L-methionyl-L-leucyl-phenylalanine (FMLP) led to a time- and dose-dependent release of LTB4, 20-OH-LTB4, 20-COOH-LTB4, 6-trans-LTB4, 12-epi-6-trans LTB4 and LTC4, as detected by reverse-phase HPLC. Preincubation of the PMN suspension in the presence of Ca2+ and Mg2+ with phorbol-12-myristate-13-acetate (PMA) did not release leukotrienes by itself, but modulated the subsequent Ca ionophore-induced leukotriene release. The release of LTC4, 20-OH-LTB4 and 20-COOH-LTB4 was significantly decreased. Lesser effects were observed for the release of LTB4 and the non-enzymatic LTB4 isomers. In contrast, opsonized zymosan and FMLP enhanced the release of LTB4 and LTB4-omega-oxidation products from cells pretreated with PMA. With arachidonic acid as prestimulus, the amounts of the LTB4 isomers (6-trans-LTB4 and 12-epi-6-trans-LTB4) were enhanced significantly on subsequent stimulation with Ca ionophore. Prestimulation of lymphocytes, monocytes and basophilic granulocytes (LMB) with PMA had no significant effects on the ionophore-induced release of LTC4 and LTB4. PMN, but not LMB, suspensions prestimulated with PMA convert exogenously added LTC4 to LTB4 isomers and LTC4 sulphoxide. Our data suggest that preincubation of human granulocytes with PMA modified leukotriene release by activation or inhibition of different metabolic pathways for LTC4 and LTB4. PMID:2838420

  3. Naringenin suppresses K562 human leukemia cell proliferation and ameliorates Adriamycin-induced oxidative damage in polymorphonuclear leukocytes

    PubMed Central

    LI, RUI-FANG; FENG, YING-QIAN; CHEN, JUN-HUI; GE, LIN-TONG; XIAO, SHU-YUAN; ZUO, XUE-LAN

    2015-01-01

    Treatments for leukemia remain unsatisfactory. Conventional chemotherapy agents that aim to kill tumor cells may also damage normal cells and thus result in severe side-effects. Naringenin, a natural polyphenolic compound with antioxidant effects, has been revealed to have significant antitumor effects with low toxicity in preliminary studies. Thus, it is considered as one of the most promising flavonoids in the treatment of leukemia. In the present study, the effects of naringenin on the K562 human leukemia cell line and the underlying mechanisms were explored in vitro. In addition, human peripheral blood polymorphonuclear leukocytes (PMNs) were used as a normal control in order to evaluate the effects of naringenin on normal granulocytes and in the mediation of Adriamycin (ADM)-induced oxidative damage. The results revealed that K562 proliferation was significantly inhibited by naringenin in a time- and concentration-dependent manner; however, minimal cytotoxic effects were observed in PMNs when naringenin was used at concentrations <400 μmol/l. Morphological changes indicative of apoptosis were observed in naringenin-treated K562 cells. Flow cytometric analysis indicated that the K562 cells were arrested in the G0/G1 phase of the cell cycle with a significantly upregulated rate of apoptosis. Furthermore, in the naringenin-treated K562 cells, the labeling index of proliferating cell nuclear antigen was observed to be increased by immunochemical staining, the mRNA and protein expression levels of p21/WAF1 were strongly upregulated in reverse transcription-polymerase chain reaction and western blot analyses, whereas p53 gene expression was not significantly changed. In PMNs to which naringenin (50~80 μmol/l) was added 1 h subsequent to ADM, the cell damage induced by ADM was significantly reduced, coincident with reductions in the levels of reactive oxygen species (ROS) and malondialdehyde (MDA) and increases in the activity of superoxide dismutase and

  4. Effects of Montelukast on free radical production in whole blood and isolated human polymorphonuclear neutrophils (PMNs) in asthmatic children

    PubMed Central

    Al Saadi, Muslim M.; Meo, Sultan Ayoub; Mustafa, Ali; Shafi, Ahmed; Tuwajri, Ali S. Al

    2011-01-01

    Montelukast is a highly selective leukotriene-receptor antagonist (LTRA). It is widely used in the treatment of bronchial asthma, primarily as an adjunct to corticosteroids. Reactive oxygen species (ROSs) play an important role in the pathogenesis of asthma and oxidative stress contributing to the initiation and worsening of inflammatory respiratory disorders, such as asthma. Antioxidant drugs may have a role in minimizing or preventing damage in asthmatic children. The aim of this study was to assess the antioxidant effect of montelukast on the production of free radicals in the whole blood and polymorphonuclear neutrophils (PMNs) in asthmatic children. A group of 48 (38 males and 10 females), apparently healthy asthmatic children were recruited with ages ranging between 6 and 14 years. In asthmatic children, base line (premedication) and post medication free radicals activity in the whole blood and polymorphonuclear neutrophils (PMNs) was determined by measuring chemiluminescence (CL) response through chemiluminescence luminometer. Free radical productions were significantly decreased in the whole blood, when stimulated with Phorbol Myristate Acetate (p < 0.04) and Opsonised Zymosan (p < 0.05). The free radicals were also significantly decreased in isolated polymorphonuclear neutrophils (PMNs) when stimulated with Opsonised Zymosan (p < 0.05) after the post medication treatment of montelukast in asthmatic children. Montelukast decreased the reactive oxygen species production, both in the whole blood as well as isolated PMNs in asthmatic children. PMID:23960762

  5. Release of platelet-activating factor (PAF) and histamine. II. The cellular origin of human PAF: monocytes, polymorphonuclear neutrophils and basophils.

    PubMed Central

    Camussi, G; Aglietta, M; Coda, R; Bussolino, F; Piacibello, W; Tetta, C

    1981-01-01

    The origin of platelet activating factor (PAF) from human leucocytes was investigated. Purified monocytes release PAF passively at pH 10.6, when challenged with Ionophore A 23187 or under phagocytic stimuli. Pure preparations of polymorphonuclear neutrophils liberate PAF passively, when challenged with C5a, neutrophil cationic proteins (CP), their carboxypeptidase B derived products (C5a des Arg, CP des Arg) or under phagocytic stimuli. Basophil rich buffy coat cells release PAF when challenged with C5a, CP, anti-IgE (in low amount) or Synacthen concomitantly with basophil degranulation and histamine release. Electron microscopy studies, carried out on Synacthen-stimulated basophil rich buffy coat, provide morphological evidence for platelet-basophil interaction. In conclusion our data demonstrate that PAF can be released from different leucocyte populations. However, the stimuli able to trigger such release appear to have some specificity for the cell target. Images Figure 5 PMID:6161885

  6. Role of gelsolin in actin depolymerization of adherent human neutrophils.

    PubMed Central

    Wang, J S; Coburn, J P; Tauber, A I; Zaner, K S

    1997-01-01

    Human neutrophils generally function adherent to an extracellular matrix. We have previously reported that upon adhesion to laminin- or fibronectin-coated, but not uncoated, plastic there is a depolymerization of actin in neutrophils. This phenomenon was not affected by inhibitors of the more well-studied components of the signal transduction pathway, specifically, pertussis toxin, an inhibitor of G-proteins, H-7 or staurosporine, inhibitors of protein kinase C, or herbimycin A, an inhibitor of nonreceptor tyrosine kinase. We therefore focused our attention on actin-binding proteins and measured the changes in the partitioning of gelsolin between the Triton X-100-soluble and -insoluble cellular fractions which occur upon neutrophil adhesion by means of quantitating anti-gelsolin antibody binding to aliquots of these fractions. It was found that approximately 90% of the total cellular gelsolin was found in the Triton X-100-soluble fraction in suspended cells, but that upon adherence to either fibronectin- or laminin-coated plastic about 40% of the soluble gelsolin could be detected in the insoluble fraction. This effect was not observed in cells adherent to uncoated plastic, wherein more than 90% of the gelsolin was found in the soluble fraction. Results of immunofluorescence microscopy of these cell preparations was consistent with this data. A gelsolin translocation to the insoluble cellular actin network may account for a part of the observed actin depolymerization. Images PMID:9017600

  7. Anti-Pseudomonas aeruginosa IgY Antibodies Induce Specific Bacterial Aggregation and Internalization in Human Polymorphonuclear Neutrophils

    PubMed Central

    Thomsen, K.; Christophersen, L.; Bjarnsholt, T.; Jensen, P. Ø.; Moser, C.

    2015-01-01

    Polymorphonuclear neutrophils (PMNs) are essential cellular constituents in the innate host response, and their recruitment to the lungs and subsequent ubiquitous phagocytosis controls primary respiratory infection. Cystic fibrosis pulmonary disease is characterized by progressive pulmonary decline governed by a persistent, exaggerated inflammatory response dominated by PMNs. The principal contributor is chronic Pseudomonas aeruginosa biofilm infection, which attracts and activates PMNs and thereby is responsible for the continuing inflammation. Strategies to prevent initial airway colonization with P. aeruginosa by augmenting the phagocytic competence of PMNs may postpone the deteriorating chronic biofilm infection. Anti-P. aeruginosa IgY antibodies significantly increase the PMN-mediated respiratory burst and subsequent bacterial killing of P. aeruginosa in vitro. The mode of action is attributed to IgY-facilitated formation of immobilized bacteria in aggregates, as visualized by fluorescence microscopy and the induction of increased bacterial hydrophobicity. Thus, the present study demonstrates that avian egg yolk immunoglobulins (IgY) targeting P. aeruginosa modify bacterial fitness, which enhances bacterial killing by PMN-mediated phagocytosis and thereby may facilitate a rapid bacterial clearance in airways of people with cystic fibrosis. PMID:25895968

  8. Formyl peptide-induced chemotaxis of human polymorphonuclear leukocytes does not require either marked changes in cytosolic calcium or specific granule discharge. Role of formyl peptide receptor reexpression (or recycling).

    PubMed Central

    Perez, H D; Elfman, F; Marder, S; Lobo, E; Ives, H E

    1989-01-01

    We examined the role of intracellular and extracellular calcium on the ability of human polymorphonuclear leukocytes to migrate chemotactically and reexpress (or recycle) formyl peptide receptors when challenged with the synthetic chemotactic peptide, N-formyl-methionyl-leucyl-phenylalanine (FMLP). Extracellular calcium was not required for either optimal chemotactic responses or receptor reexpression. Depletion and chelation of intracellular calcium resulted in significant diminution in the ability of polymorphonuclear leukocytes to release the specific granule constituents lactoferrin and vitamin B12-binding protein during the process of chemotaxis, but had no effect on the capability of these cells to respond chemotactically. Similarly, chelation of intracellular calcium did not affect the ability of these cells to reexpress a population of formyl peptide receptors. Inhibition of receptor reexpression, by a nonagglutinating derivative of wheat-germ agglutinin, was associated with inhibition of chemotactic responses to FMLP. Thus, it appears that large changes in cytosolic free calcium are not necessary for formyl peptide-induced polymorphonuclear leukocyte chemotaxis. In contrast, continuous reexpression (or recycling) of formyl peptide receptors is required for polymorphonuclear leukocyte chemotactic responses to FMLP, a process that appears to be independent from specific granule fusion with plasma membrane. PMID:2723068

  9. Intracellular calcium changes induced by the endozepine triakontatetraneuropeptide in human polymorphonuclear leukocytes: role of protein kinase C and effect of calcium channel blockers

    PubMed Central

    Marino, Franca; Cosentino, Marco; Ferrari, Marco; Cattaneo, Simona; Frigo, Giuseppina; Fietta, Anna M; Lecchini, Sergio; Frigo, Gian Mario

    2004-01-01

    Background The endozepine triakontatetraneuropeptide (TTN) induces intracellular calcium ([Ca++]i) changes followed by activation in human polymorphonuclear leukocytes (PMNs). The present study was undertaken to investigate the role of protein kinase (PK) C in the modulation of the response to TTN by human PMNs, and to examine the pharmacology of TTN-induced Ca++ entry through the plasma membrane of these cells. Results The PKC activator 12-O-tetradecanoylphorbol-13-acetate (PMA) concentration-dependently inhibited TTN-induced [Ca++]i rise, and this effect was reverted by the PKC inhibitors rottlerin (partially) and Ro 32-0432 (completely). PMA also inhibited TTN-induced IL-8 mRNA expression. In the absence of PMA, however, rottlerin (but not Ro 32-0432) per se partially inhibited TTN-induced [Ca++]i rise. The response of [Ca++]i to TTN was also sensitive to mibefradil and flunarizine (T-type Ca++-channel blockers), but not to nifedipine, verapamil (L-type) or ω-conotoxin GVIA (N-type). In agreement with this observation, PCR analysis showed the expression in human PMNs of the mRNA for all the α1 subunits of T-type Ca++ channels (namely, α1G, α1H, and α1I). Conclusions In human PMNs TTN activates PKC-modulated pathways leading to Ca++ entry possibly through T-type Ca++ channels. PMID:15228623

  10. Proenkephalin system in human polymorphonuclear cells. Production and release of a novel 1.0-kD peptide derived from synenkephalin.

    PubMed Central

    Vindrola, O; Padrós, M R; Sterin-Prync, A; Ase, A; Finkielman, S; Nahmod, V

    1990-01-01

    In the hematopoietic system a pluripotent stem cell generates precursors for lymphoid and myeloid lineages. Proenkephalin-derived peptides were previously detected in differentiated lymphoid cells. We have studied whether the proenkephalin system is expressed in a typical differentiated cell of the myeloid lineage, the neutrophil. Human peripheral polymorphonuclear cells contain and release proenkephalin-derived peptides. The opioid portion of proenkephalin (met-enkephalin-containing peptides) was incompletely processed, resulting in the absence of low molecular weight products. The nonopioid synenkephalin (proenkephalin 1-70) molecule was completely processed to a 1.0-kD peptide derived from the COOH-terminal. This molecule was characterized in neutrophils by biochemical and immunocytochemical methods. The chemotactic peptide FMLP and the calcium ionophore A23187 induced the release of the proenkephalin-derived peptides, and this effect was potentiated by cytochalasin B. The materials secreted were similar to those present in the cell, although in the supernatant a higher proportion corresponded to more processed products. The 1.0-kD peptide was detected in human, bovine, and rat neutrophils, but the chromatographic pattern of synenkephalin-derived peptides suggests a differential posttranslational processing among species. These findings demonstrate the existence of the proenkephalin system in human neutrophils and the production and release of a novel 1.0-kD peptide derived from the synenkephalin molecule. The presence of opioid peptides in neutrophils suggests their participation in the inflammatory process, including a local analgesic effect. Images PMID:2117023

  11. The mechanics of hyperactivation in adhered human sperm

    PubMed Central

    Ooi, E. H; Smith, D. J; Gadêlha, H; Gaffney, E. A; Kirkman-Brown, J

    2014-01-01

    Hyperactivation is an important phenomenon exhibited by mammalian sperm during the process of acquiring fertilization capacity. The majority of studies have focused on incubation-induced hyperactivation in non-human species, which typically differ in size, shape, and are more homogeneous than human sperm. We develop an alternative approach via drug-induction, using high-speed imaging and analysis of same-cell changes in the flagellar movement of adhered cells. Following stimulation with 4-aminopyridine, approximately two-thirds (21 of 34) of the cells analysed exhibited a waveform with a single characteristic frequency; in all cases, the frequency was lower than before stimulation. The remaining cells (13 of 34) exhibited a more complex motility with multiple-frequency modes. The lowest mode in all cases was lower than the frequency prior to stimulation. Flagellar bending increased in all cells following stimulation and was significantly greater in the multiple-frequency responders. Despite the increased bending, time-averaged hydrodynamic power dissipation decreased significantly when assessed across all cells, the effect being significantly greater in the multiple-frequency responders than single frequency. These results reveal the heterogeneity of responses of human sperm to a hyperactivating stimulus, the methodology being potentially useful for assessing dynamic responses to stimuli in human sperm, and physiological selection of cells for assisted reproduction. PMID:26064546

  12. Alcohol use, antiretroviral therapy adherence, and preferences regarding an alcohol-focused adherence intervention in patients with human immunodeficiency virus

    PubMed Central

    Kekwaletswe, Connie T; Morojele, Neo K

    2014-01-01

    Background The primary objectives of this study were to determine the association between alcohol and antiretroviral therapy (ART) adherence and the perceived appropriateness and acceptability of elements of an adherence counseling program with a focus on alcohol-related ART nonadherence among a sample of ART recipients in human immunodeficiency virus (HIV) clinics in Tshwane, South Africa. Methods We conducted a cross-sectional study with purposive sampling. The sample comprised 304 male and female ART recipients at two President’s Emergency Plan For AIDS Relief-supported HIV clinics. Using an interview schedule, we assessed patients’ alcohol use (Alcohol Use Disorders Identification Test), other drug use, level of adherence to ART, and reasons for missing ART doses (AIDS Clinical Trials Group adherence instrument). Additionally, patients’ views were solicited on: the likely effectiveness of potential facilitators; the preferred quantity, duration, format, and setting of the sessions; the usefulness of having family members/friends attend sessions along with the patient; and potential skill sets to be imparted. Results About half of the male drinkers’ and three quarters of the female drinkers’ Alcohol Use Disorders Identification Test scores were suggestive of hazardous or harmful drinking. Average self-reported ART adherence was 89.7%. There was a significant association between level of alcohol use and degree of ART adherence. Overall, participants perceived two clinic-based sessions, each of one hour’s duration, in a group format, and facilitated by a peer or adherence counselor, as most appropriate and acceptable. Participants also had a favorable attitude towards family and friends accompanying them to the sessions. They also favored an alcohol-focused adherence counseling program that employs motivational interviewing and cognitive behavioral therapy-type approaches. Conclusion The association between alcohol use and ART nonadherence points to a

  13. Regulation of 5-oxo-ETE synthesis by nitric oxide in human polymorphonuclear leucocytes upon their interaction with zymosan and Salmonella typhimurium

    PubMed Central

    Viryasova, Galina M.; Galkina, Svetlana I.; Gaponova, Tatjana V.; Romanova, Julia M.; Sud’ina, Galina F.

    2014-01-01

    In the present study we have presented data on the regulation of LT (leukotriene) and 5-oxo-ETE (5-oxo-6,8,11,14-eicosatetraenoic acid) syntheses in human neutrophils upon interaction with OZ (opsonized zymosan) or Salmonella typhimurium. Priming of neutrophils with PMA (phorbol 12-myristate 13-acetate) and LPS (lipopolysaccharide) elicits 5-oxo-ETE formation in neutrophils exposed to OZ, and the addition of AA (arachidonic acid) significantly increases 5-oxo-ETE synthesis. We found that NO (nitric oxide)-releasing compounds induce 5-oxo-ETE synthesis in neutrophils treated with OZ or S. typhimurium. Exposure of neutrophils to zymosan or bacteria in the presence of the NO donor DEA NONOate (1,1-diethyl-2-hydroxy-2-nitroso-hydrazine sodium) considerably increased the conversion of endogenously formed 5-HETE (5S-hydroxy-6,8,11,14-eicosatetraenoic acid) to 5-oxo-ETE. To our knowledge, this study is the first to demonstrate that NO is a potent regulator of 5-oxo-ETE synthesis in human polymorphonuclear leucocytes exposed to Salmonella typhimurium and zymosan. PMID:24712762

  14. Human placenta-derived adherent cells induce tolerogenic immune responses.

    PubMed

    Liu, Wei; Morschauser, Andrew; Zhang, Xin; Lu, Xiaohua; Gleason, Joseph; He, Shuyang; Chen, Hong-Jung; Jankovic, Vladimir; Ye, Qian; Labazzo, Kristen; Herzberg, Uri; Albert, Vivian R; Abbot, Stewart E; Liang, Bitao; Hariri, Robert

    2014-05-01

    Human placenta-derived adherent cells (PDAC cells) are a culture expanded, undifferentiated mesenchymal-like population derived from full-term placental tissue, with immunomodulatory and anti-inflammatory properties. PDA-001 (cenplacel-L), an intravenous formulation of PDAC cells, is in clinical development for the treatment of autoimmune and inflammatory diseases. To elucidate the mechanisms underlying the immunoregulatory properties of PDAC cells, we investigated their effects on immune cell populations, including T cells and dendritic cells (DC) in vitro and in vivo. PDAC cells suppressed T-cell proliferation in an OT-II T-cell adoptive transfer model, reduced the severity of myelin oligodendrocyte glycoprotein peptide-induced experimental autoimmune encephalomyelitis and ameliorated inflammation in a delayed type hypersensitivity response model. In vitro, PDAC cells suppressed T-cell proliferation and inhibited Th1 and Th17 differentiation. Analysis of tissues derived from PDAC cell-treated animals revealed diminished CD86 expression on splenic DC, suggesting that they can also modulate DC populations. Furthermore, PDAC cells modulate the differentiation and maturation of mouse bone marrow-derived DC. Similarly, human DC differentiated from CD14(+) monocytes in the presence of PDAC cells acquired a tolerogenic phenotype. These tolerogenic DC failed to induce allogeneic T-cell proliferation and differentiation toward Th1, but skewed T-cell differentiation toward Th2. Inhibition of cyclo-oxygenase-2 activity resulted in a significant, but not complete, abrogation of PDAC cells' effects on DC phenotype and function, implying a role for prostaglandin E2 in PDAC-mediated immunomodulation. This study identifies modulation of DC differentiation toward immune tolerance as a key mechanism underlying the immunomodulatory activities of PDAC cells. PMID:25505962

  15. Factors involved in adherence of lactobacilli to human Caco-2 cells.

    PubMed Central

    Greene, J D; Klaenhammer, T R

    1994-01-01

    A quantitative assay performed with bacterial cells labelled with [3H]thymidine was used to investigate factors involved in the adherence of human isolates Lactobacillus acidophilus BG2FO4 and NCFM/N2 and Lactobacillus gasseri ADH to human Caco-2 intestinal cells. For all three strains, adherence was concentration dependent, greater at acidic pH values, and significantly greater than adherence of a control dairy isolate, Lactobacillus delbrueckii subsp. bulgaricus 1489. Adherence of L. acidophilus BG2FO4 and NCFM/N2 was decreased by protease treatment of the bacterial cells, whereas adherence of L. gasseri ADH either was not affected or was enhanced by protease treatment. Putative surface layer proteins were identified on L. acidophilus BG2FO4 and NCFM/N2 cells but were not involved in adherence. Periodate oxidation of bacterial cell surface carbohydrates significantly reduced adherence of L. gasseri ADH, moderately reduced adherence of L. acidophilus BG2FO4, and had no effect on adherence of L. acidophilus NCFM/N2. These results indicate that Lactobacillus species adhere to human intestinal cells via mechanisms which involve different combinations of carbohydrate and protein factors on the bacterial cell surface. The involvement of a secreted bridging protein, which has been proposed as the primary mediator of adherence of L. acidophilus BG2FO4 in spent culture supernatant (M.-H. Coconnier, T. R. Klaenhammer, S. Kernéis, M.-F. Bernet, and A. L. Servin, Appl. Environ. Microbiol. 58:2034-2039, 1992), was not confirmed in this study. Rather, a pH effect on Caco-2 cells contributed significantly to the adherence of this strain in spent culture supernatant.(ABSTRACT TRUNCATED AT 250 WORDS) Images PMID:7811085

  16. Adherence of Helicobacter pylori to primary human gastrointestinal cells.

    PubMed Central

    Clyne, M; Drumm, B

    1993-01-01

    Helicobacter pylori adheres only to gastric cells in vivo. However, the organism adheres to a wide variety of nongastric cells in vitro. In this study, we have used flow cytometry to assess the adherence of H. pylori to primary epithelial cells isolated from gastric, duodenal, and colonic biopsy specimens by collagenase digestion. After incubation of bacteria and cells together and subsequent staining with a two-stage fluorescein isothiocyanate-labelled H. pylori antibody method, cells with adherent bacteria could be easily distinguished from cells without bacteria. Binding to Kato III cells (a gastric adenocarcinoma cell line) was saturable when bacteria and cells were mixed at a ratio of 250:1. Adherence to cells isolated from gastric biopsy specimens was significantly better than adherence to cells isolated from duodenal or colonic biopsy specimens. Almost 70% of gastric cells had bacteria bound, in contrast to 30% of duodenal cells and 32% of colonic cells (P < 0.0001). There was no correlation between expression of hemagglutinins by the bacteria and ability to bind to either Kato III cells or primary epithelial cells isolated from gastric biopsy specimens. In view of the strict tropism that the organism exhibits in vivo for gastric cells, the results of this study indicate that primary cells are ideal for assessing the factors that might play a role in the pathogenesis of disease caused by the organism. Images PMID:8406792

  17. Adherence of Entamoeba histolytica trophozoites to rat and human colonic mucosa.

    PubMed Central

    Ravdin, J I; John, J E; Johnston, L I; Innes, D J; Guerrant, R L

    1985-01-01

    We studied the adherence of [3H]thymidine-labeled axenic Entamoeba histolytica (strain HM1-IMSS) to in vitro preparations of rat and human colonic mucosa. Studies were performed with fixed or unfixed rat colonic mucosa, unfixed rat mucosa exposed to trypsin, unfixed rat submucosa, and fixed human colonic mucosa. Twenty percent of the amebae adhered to fixed rat colonic mucosa; adherence was specifically inhibited by N-acetyl-D-galactosamine (GalNAc), galactose, and asialofetuin. The adherence of amebae to fixed human colonic mucosa was also GalNAc inhibitable. Greater adherence was found with unfixed rat colonic mucosa (40.9%) and was not GalNAc inhibitable unless the tissue was first exposed to trypsin. However, GalNAc did inhibit the adherence of amebae to unfixed rat submucosa. Glutaraldehyde fixation of amebae inactivates known amebic adhesion proteins; there was a markedly decreased adherence of fixed amebae to trypsin-exposed mucosa or fixed rat colonic mucosa. However, fixed or viable amebae had equal levels of adherence to unfixed rat colonic mucosa, suggesting the presence of a host adhesion protein that binds to receptors on amebae. Human (10%) and rabbit (5%) immune sera reduced the adherence of viable amebae to fixed rat colonic mucosa. We concluded that the GalNAc-inhibitable adhesion protein on the surface of E. histolytica trophozoites mediated adherence to fixed rat mucosa, fixed human colonic mucosa, trypsin-exposed unfixed rat mucosa, and unfixed rat submucosa. The surface of unfixed rat colonic mucosa contained a glutaraldehyde- and trypsin-sensitive host adhesion protein, perhaps in the overlying mucus blanket, which bound viable or fixed E. histolytica trophozoites. Images PMID:2580787

  18. A Role for Lactate Dehydrogenases in the Survival of Neisseria gonorrhoeae in Human Polymorphonuclear Leukocytes and Cervical Epithelial Cells

    PubMed Central

    Atack, John M.; Ibranovic, Ines; Ong, Cheryl-Lynn Y.; Djoko, Karrera Y.; Chen, Nathan H.; vanden Hoven, Rachel; Jennings, Michael P.; Edwards, Jennifer L.; McEwan, Alastair G.

    2014-01-01

    Lactate is an abundant metabolite, produced by host tissues and commensal organisms, and it represents an important potential carbon source for bacterial pathogens. In the case of Neisseria spp., the importance of the lactate permease in colonization of the host has been demonstrated, but there have been few studies of lactate metabolism in pathogenic Neisseria in the postgenomic era. We describe herein the characterization of genome-annotated, respiratory, and substrate-level lactate dehydrogenases (LDHs) from the obligate human pathogen Neisseria gonorrhoeae. Biochemical assays using N. gonorrhoeae 1291 wild type and isogenic mutant strains showed that cytoplasmic LdhA (NAD+-dependent D-lactate dehydrogenase) and the membrane-bound respiratory enzymes, LdhD (D-lactate dehydrogenase) and LldD (L-lactate dehydrogenase) are correctly annotated. Mutants lacking LdhA and LdhD showed greatly reduced survival in neutrophils compared with wild type cells, highlighting the importance of D-lactate metabolism in gonococcal survival. Furthermore, an assay of host colonization using the well-established human primary cervical epithelial cell model revealed that the two respiratory enzymes make a significant contribution to colonization of and survival within the microaerobic environment of the host. Taken together, these data suggest that host-derived lactate is critical for the growth and survival of N. gonorrhoeae in human cells. PMID:24737798

  19. Effect of inhibitors of Na+/H+-exchange and gastric H+/K+ ATPase on cell volume, intracellular pH and migration of human polymorphonuclear leucocytes

    PubMed Central

    Ritter, M; Schratzberger, P; Rossmann, H; Wöll, E; Seiler, K; Seidler, U; Reinisch, N; Kähler, C M; Zwierzina, H; Lang, H J; Lang, F; Paulmichl, M; Wiedermann, C J

    1998-01-01

    Stimulation of chemotaxis of human polymorphonuclear leucocytes (PMNs) with the chemoattractive peptide fMLP (N-formyl-Met-Leu-Phe) is paralleled by profound morphological and metabolic alterations like changes of intracellular pH (pHi) and cell shape. The present study was performed to investigate the interrelation of cell volume (CV) regulatory ion transport, pHi and migration of fMLP stimulated PMNs.Addition of fMLP to PMNs stimulated directed migration in Boyden chamber assays and was accompanied by rapid initial intracellular acidification and cell swelling.Inhibition of the Na+/H+ exchanger suppressed fMLP stimulated cell migration, accelerated the intracellular acidification and inhibited the fMLP-induced cell swelling.Step omission of extracellular Na+ caused intracellular acidification, which was accelerated by subsequent addition of gastric H+/K+ ATPase inhibitor SCH 28080, or by omission of extracellular K+ ions. In addition Na+ removal caused cell swelling, which was further enhanced by fMLP.H+/K+ATPase inhibitors omeprazole and SCH 28080 inhibited stimulated migration and blunted the fMLP-induced increase in CV.Increasing extracellular osmolarity by addition of mannitol to the extracellular solution caused cell shrinkage followed by regulatory volume increase, partially due to activation of the Na+/H+ exchanger. In fMLP-stimulated cells the CV increase was counteracted by simultaneous addition of mannitol. Under these conditions the fMLP stimulated migration was inhibited.The antibacterial activity of PMNs was not modified by Hoe 694 or omeprazole.Western analysis with a monoclonal anti gastric H+/K+ATPase β-subunit antibody detected a glycosylated 35 kD core protein in lysates of mouse and human gastric mucosa as well as in human PMNs.The results indicate that fMLP leads to cell swelling of PMNs due to activation of the Na+/H+ exchanger and a K+-dependent H+-extruding mechanism, presumably an H+/K+ ATPase. Inhibition of these ion transporters

  20. Adherence to directly observed antiretroviral therapy among human immunodeficiency virus-infected prison inmates.

    PubMed

    Wohl, David A; Stephenson, Becky L; Golin, Carol E; Kiziah, C Nichole; Rosen, David; Ngo, Bich; Liu, Honghu; Kaplan, Andrew H

    2003-06-15

    Directly observed therapy (DOT) for human immunodeficiency virus (HIV) infection is commonly used in correctional settings; however, the efficacy of DOT for treating HIV infection has not been determined. We prospectively assessed adherence to antiretroviral therapy regimens among 31 HIV-infected prison inmates who were receiving >or=1 antiretrovirals via DOT. Adherence was measured by self-report, pill count, electronic monitoring caps, and, for DOT only, medication administration records. Overall, median adherence was 90%, as measured by pill count; 86%, by electronic monitoring caps; and 100%, by self-report. Adherence, as measured by electronic monitoring caps, was >90% in 32% of the subjects. In 91% of cases, adherence, as measured by medication administration records, was greater than that recorded by electronic monitoring caps for the same medications administered by DOT. Objective methods of measurement revealed that adherence to antiretroviral regimens administered wholly or in part by DOT was adherence revealed significantly different levels of adherence. These findings suggest that use of DOT does not ensure adherence to antiretroviral therapy. PMID:12802758

  1. Beta 2 (CD18) and beta 1 (CD29) integrin mechanisms in migration of human polymorphonuclear leucocytes and monocytes through lung fibroblast barriers: shared and distinct mechanisms.

    PubMed Central

    Shang, X Z; Issekutz, A C

    1997-01-01

    Accumulation of leucocytes in inflamed lung tissue and alveolar space involves their migration through vascular endothelium and then lung connective tissue. As a model of this process, we investigated human polymorphonuclear leucocyte (PMNL) and monocyte migration through a biological barrier of human lung fibroblasts (HLF) grown on polycarbonate filters. Very few PMNL (1-2%) or monocytes (3-8%) migrated through the HLF barriers spontaneously. Migration increased to 48-53% of added PMNL and 17-24% of added monocytes, when a C5a chemotactic gradient was present. The monocyte migration induced by C5a was not inhibited by monoclonal antibodies (mAb) to CD18 (beta 2 integrins). This CD18-independent migration was partially inhibited (35%) by mAb to gamma 5 of VLA-5 and completely inhibited by the combination of mAb to gamma 4 of VLA-4 with mAb to VLA-5, in the presence of mAb to CD18. In contrast, PMNL migration across HLF induced by C5a was partially inhibited by mAb to CD18 alone, but even with the addition of mAb to VLA-4, VLA-5 beta 1 and VLA-6, the greatest degree of inhibition was only 60%. Blocking the function of CD18 was not required to observe the inhibition by mAb to VLA-4, although the inhibitory effect of mAb to VLA-5 and VLA-6 alone or in combination was only observed when CD18 mechanisms were also blocked with anti-CD18 mAb. These results demonstrate that (a) both monocytes and PMNL can use either CD11/CD18 (beta 2 integrin) or beta 1 (CD49/CD29) integrins to migrate through HLF barriers; (b) in the case of monocytes, the VLA-4 and VLA-5 integrins account for essentially all the CD11/CD18-independent migration mechanisms; and (c) in contrast to monocytes, PMNL CD18-independent migration is mediated not only by VLA-4 and VLA-5, but also by VLA-6, and up to 40% of the migration appears to be via yet to be defined PMNL surface molecules. PMID:9497495

  2. Polymorphonuclear leucocyte migration through human dermal fibroblast monolayers is dependent on both beta 2-integrin (CD11/CD18) and beta 1-integrin (CD29) mechanisms.

    PubMed Central

    Gao, J X; Issekutz, A C

    1995-01-01

    Accumulation of leucocytes in inflammation involves their migration through vascular endothelium and then in the connective tissue. We investigated human polymorphonuclear leucocyte (PMNL) migration through a biological barrier of human dermal fibroblasts grown on microporous filters, as a model of PMNL migration in the connective tissue. PMNL did not migrate through a fibroblast monolayer unless a chemotactic factor, e.g. C5a, interleukin-8 (IL-8) or zymosan-activated plasma (ZAP; C5adesArg), was added. This migration was partially inhibited (35-70%, depending on the stimulus) by treatment of PMNL with monoclonal antibody (mAb) to CD18 (beta 2-integrins). Most of the CD18-independent migration was inhibited by mAb to beta 1-integrins (CD29). Inhibition by mAb to beta 1 was observed when the PMNL, but not the fibroblasts, were treated with mAb. The role of beta 1-integrins in PMNL transfibroblast migration was detectable only when the function of the CD11-CD18 complex was blocked, because mAb to beta 1-integrin alone had no significant effect on PMNL migration. Migration induced by C5a was more CD18-independent compared to IL-8 or C5adesArg. The CD18-independent migration was also inhibited by mAb to the beta 1-integrin subunits alpha 5 (of very late antigens-5; VLA-5) and alpha 6 (of VLA-6). Treatment of the fibroblasts (4 hr) with tumour necrosis factor-alpha (TNF-alpha) or IL-1 alpha enhanced C5a-induced PMNL transfibroblast migration and increased the proportion of migration utilizing the CD11-CD18 mechanism. However, TNF-alpha treatment had no effect on the degree of beta 1-integrin-dependent migration. These findings suggest that in response to the chemotactic factors C5a, IL-8 and C5adesArg, PMNL migration in the connective tissue is mediated by both CD11-CD18 (beta 2) and beta 1-integrins on the PMNL. The VLA-5 and VLA-6 members of beta 1-integrins are involved in this process. This is in contrast to PMNL migration across endothelium in this system, which

  3. Antiretroviral regimen and suboptimal medication adherence are associated with low-level human immunodeficiency virus viremia.

    PubMed

    Konstantopoulos, Christina; Ribaudo, Heather; Ragland, Kathleen; Bangsberg, David R; Li, Jonathan Z

    2015-01-01

    Episodes of human immunodeficiency virus low-level viremia (LLV) are common in the clinical setting, but its association with antiretroviral therapy (ART) regimen and adherence remains unclear. Antiretroviral therapy adherence was evaluated in participants of the Research on Access to Care in the Homeless cohort by unannounced pill counts. Factors associated with increased risk of LLV include treatment with a protease inhibitor (PI)-based regimen (ritonavir-boosted PI vs nonnucleoside reverse-transcriptase inhibitor: adjusted hazard ratio [HR], 3.1; P = .01) and lower ART adherence over the past 3 months (HR, 1.1 per 5% decreased adherence, adjusted; P = .050). Patients with LLV may benefit from ART adherence counseling and potentially regimen modification. PMID:25884007

  4. Enhanced adherence of methicillin-resistant Staphylococcus pseudintermedius sequence type 71 to canine and human corneocytes

    PubMed Central

    2014-01-01

    The recent worldwide spread of methicillin-resistant Staphylococcus pseudintermedius (MRSP) in dogs is a reason for concern due to the typical multidrug resistance patterns displayed by some MRSP lineages such as sequence type (ST) 71. The objective of this study was to compare the in vitro adherence properties between MRSP and methicillin-susceptible (MSSP) strains. Four MRSP, including a human and a canine strain belonging to ST71 and two canine non-ST71 strains, and three genetically unrelated MSSP were tested on corneocytes collected from five dogs and six humans. All strains were fully characterized with respect to genetic background and cell wall-anchored protein (CWAP) gene content. Seventy-seven strain-corneocyte combinations were tested using both exponential- and stationary-phase cultures. Negative binomial regression analysis of counts of bacterial cells adhering to corneocytes revealed that adherence was significantly influenced by host and strain genotype regardless of bacterial growth phase. The two MRSP ST71 strains showed greater adherence than MRSP non-ST71 (p < 0.0001) and MSSP (p < 0.0001). This phenotypic trait was not associated to any specific CWAP gene. In general, S. pseudintermedius adherence to canine corneocytes was significantly higher compared to human corneocytes (p < 0.0001), but the MRSP ST71 strain of human origin adhered equally well to canine and human corneocytes, suggesting that MRSP ST71 may be able to adapt to human skin. The genetic basis of the enhanced in vitro adherence of ST71 needs to be elucidated as this phenotypic trait may be associated to the epidemiological success and zoonotic potential of this epidemic MRSP clone. PMID:24957656

  5. Scaling up human papillomavirus vaccination: a conceptual framework of vaccine adherence

    PubMed Central

    Katz, Ingrid T.; Ware, Norma C.; Gray, Glenda; Haberer, Jessica E.; Mellins, Claude A.; Bangsberg, David R.

    2011-01-01

    This review article provides a conceptual framework for human papillomavirus (HPV) vaccine acceptance and adherence, with a focus on improving understanding of the sociocultural factors impacting vaccine adherence behaviour. We include a systematic review of the slowly expanding literature on HPV vaccine acceptability and uptake in developed nations, as well as the relatively few publications from poorer nations, where more than 80% of global cervical cancer related deaths occur and where the vaccine will probably have the largest impact. We suggest that this conceptual framework will not only improve our understanding of HPV vaccine uptake and adherence, but it may also guide future sociobehavioural research geared towards improving adherence to the HPV vaccine and other multi-step vaccines in a young population at risk for sexually transmissible infections. PMID:20719215

  6. Filamentous hemagglutinin has a major role in mediating adherence of Bordetella pertussis to human WiDr cells.

    PubMed Central

    Urisu, A; Cowell, J L; Manclark, C R

    1986-01-01

    [35S]methionine-labeled Bordetella pertussis adhered to monolayers of WiDr cells, an epitheliumlike cell line from a human intestinal carcinoma. Adherence was proportional to the density of the WiDr cells and to the concentration of B. pertussis in the assay. Adherence of virulent phase I strains Tohama phase I, 114, and BP338 was much greater than adherence of avirulent strains Tohama phase III and 423 phase IV. Mutants deficient in the production of the filamentous hemagglutinin (FHA) were hemagglutination negative and adhered to WiDr cells much less efficiently than the parent strains. Preincubation of B. pertussis cells with FHA increased their hemagglutination activity and adherence to WiDr cells. Goat antibody to FHA inhibited, in a dose-dependent manner, the adherence of strain Tohama I but not the adherence of FHA-deficient mutant Tohama 325. At similar protein concentrations, normal goat antibody, goat antibody to pertussis toxin, or the Fab fragments of goat antibody to serotype 2 fimbriae had no effect on adherence. Also, an FHA-positive strain without fimbriae showed high adherence, while a fimbriated FHA-deficient mutant adhered poorly. Our data indicate that FHA plays a major role in adherence of B. pertussis to human WiDr cells. Fimbriae do not appear to mediate attachment of B. pertussis to WiDr cells. PMID:2872165

  7. Role of carbohydrate recognition domains of pertussis toxin in adherence of Bordetella pertussis to human macrophages.

    PubMed Central

    van't Wout, J; Burnette, W N; Mar, V L; Rozdzinski, E; Wright, S D; Tuomanen, E I

    1992-01-01

    Pertussis toxin (PT) and filamentous hemagglutinin can each mediate the association of Bordetella pertussis with human macrophages. Adherence via filamentous hemagglutinin leads to integrin-mediated entry and survival of the bacteria within the human cell. We determined the contribution of PT to bacterial adherence to human macrophages. Plating macrophages on wells coated with recombinant PT subunit 2 (S2) or S3 decreased PT-dependent bacterial binding by greater than 60%; S1, S4, and S5 were ineffective. S3-dependent adherence was reduced 63% +/- 8% by sialic acid, while S2-dependent adherence was reduced 53% +/- 11% by galactose. Loss of the carbohydrate recognition properties of S2 by deletion of residues 40 to 54 or site-specific mutations at Asn-93, His-47, or Arg-50 eliminated the ability of the subunit protein to competitively inhibit bacterial binding. Peptides corresponding to residues 28 to 45 of S2 and S3 competitively inhibited adherence. Treatment of macrophages with antibodies to Le(a) or Le(x) but not CD14, CD15, CD18, or HLA interfered with PT-mediated binding. Exposure of the macrophages to the B oligomer, S2, or S3 increased binding to the CD11b/CD18 integrin. These results indicate that the carbohydrate recognition domains of both S2 and S3 participate in adherence of B. pertussis to human macrophages. The PT receptor(s), as yet unidentified, appears to carry the Le(a) or Le(x) determinants and is functionally capable of modulating integrin-mediated binding to the macrophage. PMID:1353482

  8. Oxidant-dependent metabolic activation of polycyclic aromatic hydrocarbons by phorbol ester-stimulated human polymorphonuclear leukocytes: possible link between inflammation and cancer

    SciTech Connect

    Trush, M.A.; Seed, J.L.; Kensler, T.W.

    1985-08-01

    Oxidants, such as those generated by metabolically activated phagocytes in inflammation, have been implicated in the metabolic activation of carcinogens, and in this study the authors demonstrate that the interaction of (+/-)-trans-7,8-dihydroxy-7,8-dihydrobenzo(a)pyrene (BP 7,8-dihydrodiol) with phorbol ester-stimulated polymorphonuclear leukocytes (PMNs) results in the generation of both a chemiluminescent intermediate and one that covalently binds to DNA. Concordant with the formation of a carcinogen-DNA adduct, the admixture of BP 7,8-dihydrodiol and phorbol ester-stimulated PMNs elicited mutagenesis in Salmonella typhimurium strain TA100. These results demonstrate that oxidants generated by metabolically stimulated PMNs can activate penultimate polycyclic aromatic hydrocarbons to a genotoxic metabolite and further defines a role for inflammation in carcinogenesis.

  9. Adherence to human lung microvascular endothelial cells (HMVEC-L) of Plasmodium vivax isolates from Colombia

    PubMed Central

    2013-01-01

    Background For years Plasmodium vivax has been considered the cause of benign malaria. Nevertheless, it has been observed that this parasite can produce a severe disease comparable to Plasmodium falciparum. It has been suggested that some physiopathogenic processes might be shared by these two species, such as cytoadherence. Recently, it has been demonstrated that P. vivax-infected erythrocytes (Pv-iEs) have the capacity to adhere to endothelial cells, in which intercellular adhesion molecule-1 (ICAM-1) seems to be involved in this process. Methods Adherence capacity of 21 Colombian isolates, from patients with P. vivax mono-infection to a microvascular line of human lung endothelium (HMVEC-L) was assessed in static conditions and binding was evaluated at basal levels or in tumor necrosis factor (TNF) stimulated cells. The adherence specificity for the ICAM-1 receptor was determined through inhibition with an anti-CD54 monoclonal antibody. Results The majority of P. vivax isolates, 13 out of 21 (61.9%), adhered to the HMVEC-L cells, but P. vivax adherence was at least seven times lower when compared to the four P. falciparum isolates. Moreover, HMVEC-L stimulation with TNF led to an increase of 1.6-fold in P. vivax cytoadhesion, similar to P. falciparum isolates (1.8-fold) at comparable conditions. Also, blockage of ICAM-1 receptor with specific antibodies showed a significant 50% adherence reduction. Conclusions Plasmodium vivax isolates found in Colombia are also capable of adhering specifically in vitro to lung endothelial cells, via ICAM-1 cell receptor, both at basal state and after cell stimulation with TNF. Collectively, these findings reinforce the concept of cytoadherence for P. vivax, but here, to a different endothelial cell line and using geographical distinct isolates, thus contributing to understanding P. vivax biology. PMID:24080027

  10. The effect of adherent and phagocytic cells on human lymphocyte PHA responsiveness.

    PubMed

    Potter, M R; Moore, M

    1977-01-01

    The effect of small numbers of adherent and phagocytic cells on the human peripheral blood lymphocyte response to PHA was examined by depleting these cells from lymphocyte preparations. Lymphocyte preparations obtained by centrifugation on Ficoll--Triosil, which contained on average 85% lymphocytes, responded well to PHA. Depletion of cells adhering to nylon fibre, giving a population containing on average 95% lymphocytes, resulted in a considerably reduced response. Depletion of cells that adhered to plastic or ingested iron powder to give populations containing on average 90% lymphocytes, also reduced the PHA response, but to a lesser extent. Reduction in PHA responsiveness correlated with increasing lymphocyte purity. The responsiveness of nylon-column-filtered cells could be restored by adding a small number of cells from a monocyte-rich population. PMID:300303

  11. Rat and human colonic mucins bind to and inhibit adherence lectin of Entamoeba histolytica.

    PubMed Central

    Chadee, K; Petri, W A; Innes, D J; Ravdin, J I

    1987-01-01

    Establishment of adherence by Entamoeba histolytica is mediated by a 170-kD Gal/GalNAc inhibitable lectin and is required for cytolysis and phagocytosis of mammalian target cells. We studied the biochemical mechanisms of the in vitro interaction between rat and human colonic mucins and axenic E. histolytica trophozoites. Crude mucus prevented amebic adherence to Chinese hamster ovary (CHO) cells by up to 70%. Purification of the colonic mucins by Sepharose 4B chromatography, nuclease digestion, and cesium chloride gradient centrifugation resulted in a 1,000-fold enrichment of the inhibitory mucins. Purified rat mucin inhibited amebic adherence to and cytolysis of homologous rat colonic epithelial cells. Oxidation and enzymatic cleavage of rat mucin Gal and GalNAc residues completely abrogated mucin inhibition of amebic adherence. The binding of rat 125I-mucin to amebae was galactose specific, saturable, reversible, and pH dependent. A monoclonal antibody specific for the 170-kD amebic Gal/GalNAc lectin completely inhibited the binding of rat 125I-mucin. Rat mucin bound to Affigel affinity purified the amebic lectin from conditioned medium. Colonic mucin glycoproteins act as an important host defense by binding to the parasite's adherence lectin, thus preventing amebic attachment to and cytolysis of host epithelial cells. Images PMID:2890655

  12. Antibacterial effect of the adhering human Lactobacillus acidophilus strain LB.

    PubMed

    Coconnier, M H; Liévin, V; Bernet-Camard, M F; Hudault, S; Servin, A L

    1997-05-01

    The spent culture supernatant of the human Lactobacillus acidophilus strain LB produces an antibacterial activity against a wide range of gram-negative and gram-positive pathogens. It decreased the in vitro viability of Staphylococcus aureus, Listeria monocytogenes, Salmonella typhimurium, Shigella flexneri, Escherichia coli, Klebsiella pneumoniae, Bacillus cereus, Pseudomonas aeruginosa, and Enterobacter spp. In contrast, it did not inhibit lactobacilli and bifidobacteria. The activity was heat stable and relatively sensitive to enzymatic treatments and developed under acidic conditions. The antimicrobial activity was independent of lactic acid production. Activity against S. typhimurium SL1344 infecting human cultured intestinal Caco-2 cells was observed as it was in the conventional C3H/He/oujco mouse model with S. typhimurium C5 infection and oral treatment with the LB spent culture supernatant. PMID:9145867

  13. Antibacterial effect of the adhering human Lactobacillus acidophilus strain LB.

    PubMed Central

    Coconnier, M H; Liévin, V; Bernet-Camard, M F; Hudault, S; Servin, A L

    1997-01-01

    The spent culture supernatant of the human Lactobacillus acidophilus strain LB produces an antibacterial activity against a wide range of gram-negative and gram-positive pathogens. It decreased the in vitro viability of Staphylococcus aureus, Listeria monocytogenes, Salmonella typhimurium, Shigella flexneri, Escherichia coli, Klebsiella pneumoniae, Bacillus cereus, Pseudomonas aeruginosa, and Enterobacter spp. In contrast, it did not inhibit lactobacilli and bifidobacteria. The activity was heat stable and relatively sensitive to enzymatic treatments and developed under acidic conditions. The antimicrobial activity was independent of lactic acid production. Activity against S. typhimurium SL1344 infecting human cultured intestinal Caco-2 cells was observed as it was in the conventional C3H/He/oujco mouse model with S. typhimurium C5 infection and oral treatment with the LB spent culture supernatant. PMID:9145867

  14. Nonadherent cultures of human monocytes kill Mycobacterium smegmatis, but adherent cultures do not.

    PubMed Central

    Barker, K; Fan, H; Carroll, C; Kaplan, G; Barker, J; Hellmann, W; Cohn, Z A

    1996-01-01

    Human peripheral blood monocytes are permissive for the growth of Mycobacterium tuberculosis, but the fate of nonpathogenic Mycobacterium smegmatis in these cells is not known. Since M. smegmatis may be used as a host with which to express and screen for M. tuberculosis genes needed for survival in monocytes, we determined whether human peripheral blood monocytes could restrict the growth of Mycobacterium smegmatis. Adherent human peripheral blood monocytes were permissive for the growth of M. smegmatis, as measured by ex vivo [3H]uracil uptake. However, human peripheral blood monocytes which were cultured nonadherently in Teflon wells were able to restrict the growth of M. smegmatis while remaining permissive for the growth of M. tuberculosis H37Ra. The loss of viability of M. smegmatis in nonadherent cells was correlated with an increase in nonspacious phagocytic vacuoles. The killing of M. smegmatis was not blocked by NG-monomethyl-L-arginine, suggesting that it was not due to the production of reactive nitrogen intermediates. Incubation of the monocytes for 1 to 7 days before infection had no effect on the fate of M. smegmatis, suggesting that adherence versus nonadherence, and not differentiation, was the key determinant for the difference in functional ability. Nonadherent human peripheral blood monocytes may be a more appropriate model than adherent cells for the study of factors employed by bacterial to survive within monocytes and for selection screening of bacterial genes needed for intracellular survival. PMID:8550187

  15. High Intracellular Concentrations of Posaconazole Do Not Impact on Functional Capacities of Human Polymorphonuclear Neutrophils and Monocyte-Derived Macrophages In Vitro.

    PubMed

    Farowski, Fedja; Cornely, Oliver A; Hartmann, Pia

    2016-06-01

    Posaconazole is a commonly used antifungal for the prophylaxis and treatment of invasive fungal infections. We previously demonstrated that the intracellular concentration of posaconazole in peripheral blood mononuclear cells (PBMCs) and polymorphonuclear neutrophils (PMNs) was greatly increased compared to the plasma concentration. As these professional phagocytes are crucial to combat fungal infections, we set out to investigate if and how, beneficial or deleterious, this high loading of intracellular posaconazole impacts the functional capacities of these cells. Here, we show that high intracellular concentrations of posaconazole do not significantly impact PMN and monocyte-derived macrophage function in vitro In particular, killing capacity and cytoskeletal features of PMN, such as migration, are not affected, indicating that these cells serve as vehicles for posaconazole to the site of infection. Moreover, since posaconazole as such slowed the germination of Aspergillus fumigatus conidia, infected neutrophils released less reactive oxygen species (ROS). Based on these findings, we propose that the delivery of posaconazole by neutrophils to the site of Aspergillus species infection warrants control of the pathogen and preservation of tissue integrity at the same time. PMID:27021317

  16. Oxidant-dependent metabolic activation of polycyclic aromatic hydrocarbons by phorbol ester-stimulated human polymorphonuclear leukocytes: possible link between inflammation and cancer.

    PubMed Central

    Trush, M A; Seed, J L; Kensler, T W

    1985-01-01

    Oxidants, such as those generated by metabolically activated phagocytes in inflammation, have been implicated in the metabolic activation of carcinogens, and in this study we demonstrate that the interaction of (+/-)-trans-7,8-dihydroxy-7,8-dihydrobenzo[a]pyrene (BP 7,8-dihydrodiol) with phorbol ester-stimulated polymorphonuclear leukocytes (PMNs) results in the generation of both a chemiluminescent intermediate and one that covalently binds to DNA. Cu(II)(3,5-diisopropylsalicylic acid)2 (CuDIPS), a biomimetic superoxide dismutase, and azide, a myeloperoxidase inhibitor, inhibited both of these reactions, indicating a dependency on oxygen-derived oxidants in these hydrocarbon-activation processes. Concordant with the formation of a carcinogen-DNA adduct, the admixture of BP 7,8-dihydrodiol and phorbol ester-stimulated PMNs elicited mutagenesis in Salmonella typhimurium strain TA100. 7,8-Dihydro-BP and BP cis-7,8-dihydrodiol were also mutagenic, whereas derivatives lacking a double bond at the 9,10 position were not. These results demonstrate that oxidants generated by metabolically stimulated PMNs can activate penultimate polycyclic aromatic hydrocarbons to a genotoxic metabolite and further defines a role for inflammation in carcinogenesis. PMID:2991910

  17. Age-related differences in the metabolism of sulphite to sulphate and in the identification of sulphur trioxide radical in human polymorphonuclear leukocytes.

    PubMed

    Constantin, D; Bini, A; Meletti, E; Moldeus, P; Monti, D; Tomasi, A

    1996-07-01

    Sulphite oxidation and sulphur trioxide radical formation were studied in polymorphonuclear leukocytes (PMNs) isolated from healthy young, old and centenarian donors and from patients with Down's syndrome. The sulphur radical formation measured by electron spin resonance spectroscopy-spin trapping (EPR-ST) was correlated with the activity of sulphite oxidase and with the rate of sulphite oxidation to sulphate by PMNs. Sulphite metabolism was studied both in resting, and phorbol myristate acetate (PMA) stimulated freshly isolated cells. The rate of sulphur trioxide radical formation was demonstrated by use of the spin trapping agent 5,5-dimethyl-1-pyroline-1-oxide (DMPO) with subsequent formation of an adduct. The intensity of adduct formation was most intense in cells with low sulphite oxidase activity, while a mixture of the adduct and of DMPO hydroxyl radical was mainly observed in cells with high sulphite oxidase activity. Furthermore, experiments carried out on purified sulphite oxidase showed that in the presence of sulphite the enzyme could also give rise to a DMPO-OH adduct. Sulphite oxidase activity in cells isolated from healthy young and old donors was positive correlated with both rates of sulphur trioxide radical formation and sulphite oxidation to sulphate, respectively. However, sulphite oxidase activity in cells isolated from centenarians and patients with Down's syndrome seems to loose partly its rate of oxidising sulphite to sulphate. The intensity of the sulphur centred radical adduct increased in the two latter groups of population and the radical observed was predominantly sulphur trioxide radical. PMID:8803926

  18. Mechanisms of adherence of Candida albicans to cultured human epidermal keratinocytes.

    PubMed Central

    Ollert, M W; Söhnchen, R; Korting, H C; Ollert, U; Bräutigam, S; Bräutigam, W

    1993-01-01

    We established an in vitro adherence model with primarily cultured human keratinocytes as target cells which allows for the investigation of the molecular mechanisms that are responsible for Candida albicans host cell attachment in the initiation of cutaneous candidosis. The extent of C. albicans binding to cultured human keratinocytes was dependent on the yeast inoculum size and the incubation temperature. Heat and paraform-aldehyde treatment of yeasts completely abolished the binding activity of C. albicans. Of the different Candida species tested, C. albicans was by far the most adhesive species. C. albicans adherence was blocked by the acid protease inhibitor pepstatin A and the metabolic inhibitor sodium azide. The latter, however, was much less effective when yeasts were preincubated, suggesting that sodium azide was mainly acting on the keratinocytes. The extracellular matrix protein fibronectin was slightly inhibitory, whereas the fibronectin-derived peptides RGD and RGDS were not able to prevent attachment. PepTite-2000, another RGD-containing synthetic peptide, reduced C. albicans adherence by a margin of 25% (P < 0.005). CDPGYIGSR-NH2, which is a synthetic adhesive peptide derived from the laminin B chain, was much more efficient in its inhibitory activity than the RGD peptides and reduced C. albicans adherence to cultured human keratinocytes up to 76% (P < 0.001). Laminin itself and the synthetic pentapeptide YIGSR were less active. A dose-dependent reduction in adherence was also observed with collagen type III. Additionally, saccharides were tested for their potential to inhibit C. albicans attachment to keratinocytes. The most potent competitive saccharide inhibitors of C. albicans adherence to human keratinocytes were the amino sugars D-(+)-glucosamine and D-(+)-galactosamine with one isolate of C. albicans (4918) and D-(+)-glucosamine and alpha-D-(+)-fucose with another C. albicans isolate (Sp-1). Collectively, our data suggest the existence of

  19. Adherence of human oral keratinocytes and gingival fibroblasts to nano-structured titanium surfaces

    PubMed Central

    2014-01-01

    Background A key element for long-term success of dental implants is integration of the implant surface with the surrounding host tissues. Modification of titanium implant surfaces can enhance osteoblast activity but their effects on soft-tissue cells are unclear. Adherence of human keratinocytes and gingival fibroblasts to control commercially pure titanium (CpTi) and two surfaces prepared by anodic oxidation was therefore investigated. Since implant abutments are exposed to a bacteria-rich environment in vivo, the effect of oral bacteria on keratinocyte adhesion was also evaluated. Methods The surfaces were characterized using scanning electron microscopy (SEM). The number of adhered cells and binding strength, as well as vitality of fibroblasts and keratinocytes were evaluated using confocal scanning laser microscopy after staining with Live/Dead Baclight. To evaluate the effect of bacteria on adherence and vitality, keratinocytes were co-cultured with a four-species streptococcal consortium. Results SEM analysis showed the two anodically oxidized surfaces to be nano-structured with differing degrees of pore-density. Over 24 hours, both fibroblasts and keratinocytes adhered well to the nano-structured surfaces, although to a somewhat lesser degree than to CpTi (range 42-89% of the levels on CpTi). The strength of keratinocyte adhesion was greater than that of the fibroblasts but no differences in adhesion strength could be observed between the two nano-structured surfaces and the CpTi. The consortium of commensal streptococci markedly reduced keratinocyte adherence on all the surfaces as well as compromising membrane integrity of the adhered cells. Conclusion Both the vitality and level of adherence of soft-tissue cells to the nano-structured surfaces was similar to that on CpTi. Co-culture with streptococci reduced the number of keratinocytes on all the surfaces to approximately the same level and caused cell damage, suggesting that commensal bacteria could

  20. Monoclonal Lym-1 antibody-dependent lysis of B-lymphoblastoid tumor targets by human complement and cytokinine-exposed mononuclear and neutrophilic polymorphonuclear leukocytes.

    PubMed

    Ottonello, L; Morone, P; Dapino, P; Dallegri, F

    1996-06-15

    Lym-1 is a murine IgG2a monoclonal antibody that recognizes a polymorphic variant of HLA-DR antigens on malignant B cells, with minimal cross-reactivity with normal tissues. Because it can be safely administered in vivo, a detailed knowledge of its ability to recruit and trigger the antitumor immune effector systems is required to optimize potential serotherapeutic approaches in B-lymphoma patients. By using Raji cells as a model of B-lymphoma targets, we found that Lym-1 activates complement-mediated lysis efficiently. Moreover, Lym-1 was capable of triggering the antibody-dependent cellular cytolysis (ADCC) by peripheral blood mononuclear cells (MNCs). On the contrary, it failed to trigger neutrophilic polymorphonuclear leukocyte (PMN)-mediated ADCC activity. In an attempt to enhance Lym-1 ADCC by MNCs and PMNs, nine biologic response modifiers were tested. MNC-mediated Lym-1 ADCC was significantly stimulated by interleukin-2 (IL-2) and unaffected by other mediators, including gamma-interferon (gamma-IFN), tumor necrosis factor a (TNFalpha), and granulocyte-macrophage colony-stimulating factor (GM-CSF). On the other hand, PMN-mediated Lym-1 ADCC was induced or significantly augmented by various cytokines, such as GM-CSF, TNFalpha, and gamma-IFN, and chemotaxins, such as formyl peptides (FMLP), complement fragment C5a, and IL-8. Both MNC- and PMN-mediated ADCC was unaffected by granulocyte colony-stimulating factor (G- CSF) and insulin-like growth factor-1 (IGF-1). Finally, only GM-CSF and TNFalpha augmented the number of PMNs actually engaged in the binding of Raji target cells. The findings presented here, in particular those showing stimulatory activity of biologic response modifiers, may inspire new attempts for developing Lym-1 antibody-based approaches to the therapy of B lymphomas. PMID:8652830

  1. Supportive Accountability: A Model for Providing Human Support to Enhance Adherence to eHealth Interventions

    PubMed Central

    2011-01-01

    The effectiveness of and adherence to eHealth interventions is enhanced by human support. However, human support has largely not been manualized and has usually not been guided by clear models. The objective of this paper is to develop a clear theoretical model, based on relevant empirical literature, that can guide research into human support components of eHealth interventions. A review of the literature revealed little relevant information from clinical sciences. Applicable literature was drawn primarily from organizational psychology, motivation theory, and computer-mediated communication (CMC) research. We have developed a model, referred to as “Supportive Accountability.” We argue that human support increases adherence through accountability to a coach who is seen as trustworthy, benevolent, and having expertise. Accountability should involve clear, process-oriented expectations that the patient is involved in determining. Reciprocity in the relationship, through which the patient derives clear benefits, should be explicit. The effect of accountability may be moderated by patient motivation. The more intrinsically motivated patients are, the less support they likely require. The process of support is also mediated by the communications medium (eg, telephone, instant messaging, email). Different communications media each have their own potential benefits and disadvantages. We discuss the specific components of accountability, motivation, and CMC medium in detail. The proposed model is a first step toward understanding how human support enhances adherence to eHealth interventions. Each component of the proposed model is a testable hypothesis. As we develop viable human support models, these should be manualized to facilitate dissemination. PMID:21393123

  2. Supportive accountability: a model for providing human support to enhance adherence to eHealth interventions.

    PubMed

    Mohr, David C; Cuijpers, Pim; Lehman, Kenneth

    2011-01-01

    The effectiveness of and adherence to eHealth interventions is enhanced by human support. However, human support has largely not been manualized and has usually not been guided by clear models. The objective of this paper is to develop a clear theoretical model, based on relevant empirical literature, that can guide research into human support components of eHealth interventions. A review of the literature revealed little relevant information from clinical sciences. Applicable literature was drawn primarily from organizational psychology, motivation theory, and computer-mediated communication (CMC) research. We have developed a model, referred to as "Supportive Accountability." We argue that human support increases adherence through accountability to a coach who is seen as trustworthy, benevolent, and having expertise. Accountability should involve clear, process-oriented expectations that the patient is involved in determining. Reciprocity in the relationship, through which the patient derives clear benefits, should be explicit. The effect of accountability may be moderated by patient motivation. The more intrinsically motivated patients are, the less support they likely require. The process of support is also mediated by the communications medium (eg, telephone, instant messaging, email). Different communications media each have their own potential benefits and disadvantages. We discuss the specific components of accountability, motivation, and CMC medium in detail. The proposed model is a first step toward understanding how human support enhances adherence to eHealth interventions. Each component of the proposed model is a testable hypothesis. As we develop viable human support models, these should be manualized to facilitate dissemination. PMID:21393123

  3. Lactobacillus reuteri Inhibition of Enteropathogenic Escherichia coli Adherence to Human Intestinal Epithelium.

    PubMed

    Walsham, Alistair D S; MacKenzie, Donald A; Cook, Vivienne; Wemyss-Holden, Simon; Hews, Claire L; Juge, Nathalie; Schüller, Stephanie

    2016-01-01

    Enteropathogenic Escherichia coli (EPEC) is a major cause of diarrheal infant death in developing countries, and probiotic bacteria have been shown to provide health benefits in gastrointestinal infections. In this study, we have investigated the influence of the gut symbiont Lactobacillus reuteri on EPEC adherence to the human intestinal epithelium. Different host cell model systems including non-mucus-producing HT-29 and mucus-producing LS174T intestinal epithelial cell lines as well as human small intestinal biopsies were used. Adherence of L. reuteri to HT-29 cells was strain-specific, and the mucus-binding proteins CmbA and MUB increased binding to both HT-29 and LS174T cells. L. reuteri ATCC PTA 6475 and ATCC 53608 significantly inhibited EPEC binding to HT-29 but not LS174T cells. While pre-incubation of LS174T cells with ATCC PTA 6475 did not affect EPEC attaching/effacing (A/E) lesion formation, it increased the size of EPEC microcolonies. ATCC PTA 6475 and ATCC 53608 binding to the mucus layer resulted in decreased EPEC adherence to small intestinal biopsy epithelium. Our findings show that L. reuteri reduction of EPEC adhesion is strain-specific and has the potential to target either the epithelium or the mucus layer, providing further rationale for the selection of probiotic strains. PMID:26973622

  4. Lactobacillus reuteri Inhibition of Enteropathogenic Escherichia coli Adherence to Human Intestinal Epithelium

    PubMed Central

    Walsham, Alistair D. S.; MacKenzie, Donald A.; Cook, Vivienne; Wemyss-Holden, Simon; Hews, Claire L.; Juge, Nathalie; Schüller, Stephanie

    2016-01-01

    Enteropathogenic Escherichia coli (EPEC) is a major cause of diarrheal infant death in developing countries, and probiotic bacteria have been shown to provide health benefits in gastrointestinal infections. In this study, we have investigated the influence of the gut symbiont Lactobacillus reuteri on EPEC adherence to the human intestinal epithelium. Different host cell model systems including non-mucus-producing HT-29 and mucus-producing LS174T intestinal epithelial cell lines as well as human small intestinal biopsies were used. Adherence of L. reuteri to HT-29 cells was strain-specific, and the mucus-binding proteins CmbA and MUB increased binding to both HT-29 and LS174T cells. L. reuteri ATCC PTA 6475 and ATCC 53608 significantly inhibited EPEC binding to HT-29 but not LS174T cells. While pre-incubation of LS174T cells with ATCC PTA 6475 did not affect EPEC attaching/effacing (A/E) lesion formation, it increased the size of EPEC microcolonies. ATCC PTA 6475 and ATCC 53608 binding to the mucus layer resulted in decreased EPEC adherence to small intestinal biopsy epithelium. Our findings show that L. reuteri reduction of EPEC adhesion is strain-specific and has the potential to target either the epithelium or the mucus layer, providing further rationale for the selection of probiotic strains. PMID:26973622

  5. A mannose-specific adherence mechanism in Lactobacillus plantarum conferring binding to the human colonic cell line HT-29.

    PubMed Central

    Adlerberth, I; Ahrne, S; Johansson, M L; Molin, G; Hanson, L A; Wold, A E

    1996-01-01

    Two Lactobacillus plantarum strains of human intestinal origin, strains 299 (= DSM 6595) and 299v (= DSM 9843), have proved to be efficient colonizers of the human intestine under experimental conditions. These strains and 17 other L. plantarum strains were tested for the ability to adhere to cells of the human colonic cell line HT-29.L.plantarum 299 and 299v and nine other L. plantarum strains, including all six strains that belong to the same genetic subgroup as L. plantarum 299 and 299v, adhered to HT-29 cells in a manner that could be inhibited by methyl-alpha-D-mannoside. The ability to adhere to HT-29 cells correlated with an ability to agglutinate cells of Saccharomyces cerevisiae and erythrocytes in a mannose-sensitive manner and with adherence to D-mannose-coated agarose beads. L. plantarum 299 and 299v adhered to freshly isolated human colonic and ileal enterocytes, but the binding was not significantly inhibited by methyl-alpha-D-mannoside. Periodate treatment of HT-29 cells abolished mannose-sensitive adherence, confirming that the cell-bound receptor was of carbohydrate nature. Proteinase K treatment of the bacteria also abolished adherence, indicating that the binding involved protein structures on the bacterial cell surface. Thus, a mannose-specific adhesin has been identified in L. plantarum; this adhesin could be involved in the ability to colonize the intestine. PMID:8779562

  6. Poly(ethylene glycol)-containing hydrogels modulate α-defensin release from polymorphonuclear leukocytes and monocyte recruitment.

    PubMed

    Lieberthal, Tyler Jacob; Cohen, Hannah Caitlin; Kao, W John

    2015-12-01

    Polymorphonuclear leukocytes (PMNs) release granule proteins as the first line of defense against bacteria and set up chemotactic gradients that result in monocyte infiltration to the site of injury. Although well established, the role of biomaterials in regulating adherent PMN degranulation and subsequent PMN-monocyte paracrine interactions is less clear. The aim of this study was to determine how biomaterials affect the degranulation of selected biomarkers and downstream monocyte adhesion and transendothelial migration. Poly(ethylene glycol) (PEG)-containing hydrogels (PEG and an interpenetrating network of PEG and gelatin) promote the release of the α-defensins human neutrophil peptides 1-3, but not azurocidin or monocyte chemotactic protein-1. Although human neutrophil peptides 1-3 are monocyte chemoattractants, no subsequent effects on monocyte transmigration are observed in static conditions. Under flow conditions, monocyte adhesion on human umbilical vein endothelial cells stimulated with tumor necrosis factor-α is elevated in the presence of granule proteins from PMNs adherent on polydimethylsiloxane, but not from PMNs cultured on PEG hydrogels. These results suggest that PEG promotes PMN antimicrobial capacity without enhanced monocyte recruitment. PMID:26053326

  7. Inhibition of benzo[a]pyrene-induced mouse forestomach neoplasia and reduction of H2O2 concentration in human polymorphonuclear leucocytes by flavour components of Japanese-style fermented soy sauce.

    PubMed

    Kataoka, S; Liu, W; Albright, K; Storkson, J; Pariza, M

    1997-05-01

    Previously it was reported that 4-hydroxy-2 (or 5)-ethyl-5 (or 2)-methyl-3(2H)-furanone (HEMF), a characteristic flavour component of Japanese-style fermented soy sauce that exhibits antioxidant activity, inhibits benzo[a]pyrene-induced forestomach neoplasia in mice. The antioxidant and anticarcinogenic activities of other structurally similar soy sauce flavour components are now reported. 4-Hydroxy-5-methyl-3(2H)-furanone (HMF) and 4-hydroxy-2,5-dimethyl-3(2H)-furanone (HDMF) were found to be antioxidants. In particular, HMF and HDMF (as well as HEMF) reduced hydrogen peroxide concentration in human polymorphonuclear leucocytes stimulated by arachidonic acid or 12-O-tetradecanoylphorbol-13-acetate. HMF and HDMF were administered individually in semipurified diet to female ICR mice previously treated with benzo[a]pyrene (1.5 mg/wk, orally for 4 wk) to initiate forestomach neoplasia. The mice were killed at 30 wk of age. Both furanones reduced forestomach neoplasms, with HDMF exhibiting more potency. The data indicate that HDMF and HMF, like HEMF, inhibit carcinogenesis in this system by acting at the post-initiation stage. PMID:9216743

  8. Enterotoxigenic Escherichia coli TibA Glycoprotein Adheres to Human Intestine Epithelial Cells

    PubMed Central

    Lindenthal, Christoph; Elsinghorst, Eric A.

    2001-01-01

    Enterotoxigenic Escherichia coli (ETEC) is capable of invading epithelial cell lines derived from the human ileum and colon. Two separate invasion loci (tia and tib) that direct noninvasive E. coli strains to adhere to and invade cultured human intestine epithelial cells have previously been isolated from the classical ETEC strain H10407. The tib locus directs the synthesis of TibA, a 104-kDa outer membrane glycoprotein. Synthesis of TibA is directly correlated with the adherence and invasion phenotypes of the tib locus, suggesting that this protein is an adhesin and invasin. Here we report the purification of TibA and characterization of its biological activity. TibA was purified by continuous-elution preparative sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Purified TibA was biotin labeled and then shown to bind to HCT8 human ileocecal epithelial cells in a specific and saturable manner. Unlabeled TibA competed with biotin-labeled TibA, suggesting the presence of a specific TibA receptor in HCT8 cells. These results show that TibA acts as an adhesin. Polyclonal anti-TibA antiserum inhibited invasion of ETEC strain H10407 and of recombinant E. coli bearing tib locus clones, suggesting that TibA also acts as an invasin. The ability of TibA to direct epithelial cell adhesion suggests a role for this protein in ETEC pathogenesis. PMID:11119488

  9. Enterotoxigenic Escherichia coli TibA glycoprotein adheres to human intestine epithelial cells.

    PubMed

    Lindenthal, C; Elsinghorst, E A

    2001-01-01

    Enterotoxigenic Escherichia coli (ETEC) is capable of invading epithelial cell lines derived from the human ileum and colon. Two separate invasion loci (tia and tib) that direct noninvasive E. coli strains to adhere to and invade cultured human intestine epithelial cells have previously been isolated from the classical ETEC strain H10407. The tib locus directs the synthesis of TibA, a 104-kDa outer membrane glycoprotein. Synthesis of TibA is directly correlated with the adherence and invasion phenotypes of the tib locus, suggesting that this protein is an adhesin and invasin. Here we report the purification of TibA and characterization of its biological activity. TibA was purified by continuous-elution preparative sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Purified TibA was biotin labeled and then shown to bind to HCT8 human ileocecal epithelial cells in a specific and saturable manner. Unlabeled TibA competed with biotin-labeled TibA, suggesting the presence of a specific TibA receptor in HCT8 cells. These results show that TibA acts as an adhesin. Polyclonal anti-TibA antiserum inhibited invasion of ETEC strain H10407 and of recombinant E. coli bearing tib locus clones, suggesting that TibA also acts as an invasin. The ability of TibA to direct epithelial cell adhesion suggests a role for this protein in ETEC pathogenesis. PMID:11119488

  10. Trichomonas vaginalis lipophosphoglycan mutants have reduced adherence and cytotoxicity to human ectocervical cells.

    PubMed

    Bastida-Corcuera, Felix D; Okumura, Cheryl Y; Colocoussi, Angie; Johnson, Patricia J

    2005-11-01

    The extracellular human pathogen Trichomonas vaginalis is covered by a dense glycocalyx thought to play a role in host-parasite interactions. The main component of the glycocalyx is lipophosphoglycan (LPG), a polysaccharide anchored in the plasma membrane by inositol phosphoceramide. To study the role of LPG in trichomonads, we produced T. vaginalis LPG mutants by chemical mutagenesis and lectin selection and characterized them using morphological, biochemical, and functional assays. Two independently selected LPG mutants, with growth rates comparable to that of the wild-type (parent) strain, lost the ability to bind the lectins Ricinnus comunis agglutinin I (RCA120) and wheat germ agglutinin, indicating alterations in surface galactose and glucosamine residues. LPG isolated from mutants migrated faster than parent strain LPG on sodium dodecyl sulfate-polyacrylamide gel electrophoresis, suggesting the mutants had shorter LPG molecules. Dionex high-performance anion exchange chromatography with pulsed amperometric detection analyses revealed galactosamine, glucosamine, galactose, glucose, mannose/xylose, and rhamnose as the main monosaccharides of T. vaginalis parent strain LPG. LPG from both mutants showed a reduction of galactose and glucosamine, corresponding with the reduced size of their LPG molecules and inability to bind the lectins RCA120 and wheat germ agglutinin. Mutant parasites were defective in attachment to plastic, a characteristic associated with avirulent strains of T. vaginalis. Moreover, the mutants were less adherent and less cytotoxic to human vaginal ectocervical cells in vitro than the parental strain. Finally, while parent strain LPG could inhibit the attachment of parent strain parasites to vaginal cells, LPG from either mutant could not inhibit attachment. These combined results demonstrate that T. vaginalis adherence to host cells is LPG mediated and that an altered LPG leads to reduced adherence and cytotoxicity of this parasite. PMID

  11. Trichomonas vaginalis Lipophosphoglycan Mutants Have Reduced Adherence and Cytotoxicity to Human Ectocervical Cells

    PubMed Central

    Bastida-Corcuera, Felix D.; Okumura, Cheryl Y.; Colocoussi, Angie; Johnson, Patricia J.

    2005-01-01

    The extracellular human pathogen Trichomonas vaginalis is covered by a dense glycocalyx thought to play a role in host-parasite interactions. The main component of the glycocalyx is lipophosphoglycan (LPG), a polysaccharide anchored in the plasma membrane by inositol phosphoceramide. To study the role of LPG in trichomonads, we produced T. vaginalis LPG mutants by chemical mutagenesis and lectin selection and characterized them using morphological, biochemical, and functional assays. Two independently selected LPG mutants, with growth rates comparable to that of the wild-type (parent) strain, lost the ability to bind the lectins Ricinnus comunis agglutinin I (RCA120) and wheat germ agglutinin, indicating alterations in surface galactose and glucosamine residues. LPG isolated from mutants migrated faster than parent strain LPG on sodium dodecyl sulfate-polyacrylamide gel electrophoresis, suggesting the mutants had shorter LPG molecules. Dionex high-performance anion exchange chromatography with pulsed amperometric detection analyses revealed galactosamine, glucosamine, galactose, glucose, mannose/xylose, and rhamnose as the main monosaccharides of T. vaginalis parent strain LPG. LPG from both mutants showed a reduction of galactose and glucosamine, corresponding with the reduced size of their LPG molecules and inability to bind the lectins RCA120 and wheat germ agglutinin. Mutant parasites were defective in attachment to plastic, a characteristic associated with avirulent strains of T. vaginalis. Moreover, the mutants were less adherent and less cytotoxic to human vaginal ectocervical cells in vitro than the parental strain. Finally, while parent strain LPG could inhibit the attachment of parent strain parasites to vaginal cells, LPG from either mutant could not inhibit attachment. These combined results demonstrate that T. vaginalis adherence to host cells is LPG mediated and that an altered LPG leads to reduced adherence and cytotoxicity of this parasite. PMID

  12. Purification and characterization by fast-atom-bombardment mass spectrometry of the polymorphonuclear-leucocyte-elastase-generated A alpha (1-21) fragment of fibrinogen from human blood after incubation with calcium ionophore A23187.

    PubMed Central

    Dewey, R S; Liesch, J M; Williams, H R; Sugg, E E; Dolan, C A; Davies, P; Mumford, R A; Albers-Schönberg, G

    1992-01-01

    The stimulation of human blood with a Ca2+ ionophore, A23187, leads to activation of polymorphonuclear leucocytes (PMN) with release of small amounts of catalyticaly active elastase, as demonstrated by the formation of a characteristic product, the N-terminal A alpha (1-21) peptide of the Aa subunit of fibrinogen. The identity of the peptide was initially established by radioimmunoassay (r.i.a.) with an antibody raised to A alpha (1-21). We now provide independent confirmation of the formation of A alpha (1-21) by fast-atom-bombardment-m.s. analysis of the fractions separated chromatographically after spiking of plasma samples with peptide labelled with [2H8]Phe at position 8. Identity of the peptides was established on the basis of their chromatographic retention time and by the distinct peaks in the mass spectra of these fractions. The relative intensities of the molecular ions of natural and labelled peptides were measured. On the basis of a comparison of the peaks of similar intensities, the concentration of the natural peptide at the time of spiking was close (79%) to the amount obtained by r.i.a. An additional peptide, des-alanyl-A alpha (2-21), was also seen. The total amount of material measured by r.i.a. could be accounted for by the sum of these two provides. The addition of label and assay by m.s. has provided an independent physical-chemical method for identifying A alpha (1-21) as a characteristic product of PMN elastase release in whole blood, but which is absent in freshly drawn blood. PMID:1736899

  13. CsrRS and environmental pH regulate group B streptococcus adherence to human epithelial cells and extracellular matrix.

    PubMed

    Park, Su Eun; Jiang, Shengmei; Wessels, Michael R

    2012-11-01

    Streptococcus agalactiae (group B Streptococcus or GBS) is a common colonizer of the gastrointestinal and genital tracts and an important cause of invasive infections in newborn infants and in adults with predisposing chronic conditions or advanced age. Attachment to epithelial surfaces at mucosal sites is a critical step in the successful colonization of a human host, and regulation of this process is likely to play an important role in both commensalism and dissemination to cause invasive disease. We found that inactivation of the CsrRS (or CovRS) two-component system increased GBS adherence to epithelial cells derived from human vaginal, cervical, and respiratory epithelium, as well as increasing adherence to extracellular matrix proteins and increasing biofilm formation on polystyrene. Neutral (as opposed to acidic) pH enhanced GBS binding to vaginal epithelial cells and to fibrinogen and fibronectin, effects that were partially dependent on CsrRS. The regulatory effects of CsrRS and environmental pH on bacterial adherence correlated with their effects on the expression of multiple surface adhesins, as assessed by quantitative reverse transcription-PCR. We conclude that GBS adherence to epithelial and abiotic surfaces is regulated by the CsrRS two-component system and by environmental pH through their regulatory effects on the expression of bacterial surface adhesins. Dynamic regulation of GBS adherence enhances the organism's adaptability to survival in multiple niches in the human host. PMID:22949550

  14. CsrRS and Environmental pH Regulate Group B Streptococcus Adherence to Human Epithelial Cells and Extracellular Matrix

    PubMed Central

    Park, Su Eun; Jiang, Shengmei

    2012-01-01

    Streptococcus agalactiae (group B Streptococcus or GBS) is a common colonizer of the gastrointestinal and genital tracts and an important cause of invasive infections in newborn infants and in adults with predisposing chronic conditions or advanced age. Attachment to epithelial surfaces at mucosal sites is a critical step in the successful colonization of a human host, and regulation of this process is likely to play an important role in both commensalism and dissemination to cause invasive disease. We found that inactivation of the CsrRS (or CovRS) two-component system increased GBS adherence to epithelial cells derived from human vaginal, cervical, and respiratory epithelium, as well as increasing adherence to extracellular matrix proteins and increasing biofilm formation on polystyrene. Neutral (as opposed to acidic) pH enhanced GBS binding to vaginal epithelial cells and to fibrinogen and fibronectin, effects that were partially dependent on CsrRS. The regulatory effects of CsrRS and environmental pH on bacterial adherence correlated with their effects on the expression of multiple surface adhesins, as assessed by quantitative reverse transcription-PCR. We conclude that GBS adherence to epithelial and abiotic surfaces is regulated by the CsrRS two-component system and by environmental pH through their regulatory effects on the expression of bacterial surface adhesins. Dynamic regulation of GBS adherence enhances the organism's adaptability to survival in multiple niches in the human host. PMID:22949550

  15. Recognition of an endothelial determinant for CD 18-dependent human neutrophil adherence and transendothelial migration.

    PubMed Central

    Smith, C W; Rothlein, R; Hughes, B J; Mariscalco, M M; Rudloff, H E; Schmalstieg, F C; Anderson, D C

    1988-01-01

    Human neutrophil (PMN) attachment to human umbilical vein endothelial cells (HUVEC) was evaluated in vitro using two MAbs, R6-5-D6 and RR1/1, that recognize intercellular adhesion molecule-1 (ICAM-1), and one MAb, TS1/18, that recognizes CD18. Pretreatment of the HUVEC with anti-ICAM-1 MAbs produced greater than 50% inhibition of attachment to HUVEC, and IL-1 (0.5 U/ml)- or lipopolysaccharide (LPS) (10 ng/ml)-stimulated HUVEC, and greater than 99% inhibition of f-Met-Leu-Phe (0.5 nM) enhanced adherence. Anti-ICAM-1 MAbs also inhibited by greater than 85% the transendothelial migration induced by 4-h IL-1 (0.5 U/ml) and LPS (10 ng/ml) activation of the HUVEC. That these effects involved a CD18-dependent mechanism is supported by the following results: pretreatment of PMN with TS1/18 produced the same degree of inhibition of attachment and migration as seen with R6-5-D6. In addition, the use of both MAbs together did not further increase the inhibition of cell attachment to stimulated HUVEC. The attachment of PMN from patients with CD18 deficiency to stimulated HUVEC was not reduced by R6-5-D6, and both R6-5-D6 and TS1/18 revealed the same time course for appearance and disappearance of an adherence component on stimulated HUVEC not blocked by either MAb. These results demonstrate that attachment and transendothelial migration of PMN in vitro depend substantially on both CD18 on the PMN and ICAM-1 on the endothelial cell. Images PMID:2903180

  16. Human responses to Florida red tides: policy awareness and adherence to local fertilizer ordinances.

    PubMed

    Kirkpatrick, Barbara; Kohler, Kate; Byrne, Margaret; Fleming, Lora E; Scheller, Karen; Reich, Andrew; Hitchcock, Gary; Kirkpatrick, Gary; Ullmann, Steven; Hoagland, Porter

    2014-09-15

    To mitigate the damages of natural hazards, policy responses can be beneficial only if they are effective. Using a self-administered survey approach, this paper focuses on the adherence to local fertilizer ordinances (i.e., county or municipal rules regulating the application of fertilizer to private lawns or facilities such as golf courses) implemented in jurisdictions along the Southwest Florida coast in response to hazardous blooms of Florida red tides (Karenia brevis). These ordinances play a role in the context of evolving programs of water pollution control at federal, state, water basin, and local levels. With respect to policy effectiveness, while the strength of physical linkages is of critical importance, the extent to which humans affected are aware of and adhere to the relevant rules, is equally critical. We sought to understand the public's depth of understanding about the rationales for local fertilizer ordinances. Respondents in Sarasota, Florida, were asked about their fertilizer practices in an area that has experienced several major blooms of Florida red tides over the past two decades. A highly educated, older population of 305 residents and "snowbirds" reported relatively little knowledge about a local fertilizer ordinance, its purpose, or whether it would change the frequency, size, or duration of red tides. This finding held true even among subpopulations that were expected to have more interest in or to be more knowledgeable about harmful algal blooms. In the face of uncertain science and environmental outcomes, and with individual motivations at odds with evolving public policies, the effectiveness of local community efforts to decrease the impacts of red tides may be compromised. Targeted social-science research on human perceptions about the risks of Florida red tides and education about the rationales for potential policy responses are warranted. PMID:25003583

  17. Lymphoblastoid cell supernatants increase expression of C3b receptors on human polymorphonuclear leucocytes: direct binding studies with 125I-C3b.

    PubMed Central

    Berger, M; Cross, A S

    1984-01-01

    Human PMN incubated in culture supernatants of the Raji long-term human lymphoblastoid cell line showed increased rosette formation with sheep erythrocytes coated with C3b (EIgM C4b3b) but no change in rosette formation with IgG-coated erythrocytes. This suggested a specific increase in cell surface C3b receptors, which was further investigated using 125I-C3b for direct binding studies. The results confirmed that specific binding of 125I-C3b to PMN incubated in culture supernatants increased up to three- to four-fold over binding to PMN incubated in control media alone. Scatchard analysis revealed that the apparent Ka for supernatant-treated cells, 3.36 +/- 0.89 X 10(7) L/M did not differ from the Ka for cells incubated in control media, 3.76 +/- 0.75 X 10(7) L/M, suggesting an increase in a single class of C3b receptors. Kinetic studies revealed that the active factor was present within 24 hr of culture of the Raji cells, and that neutrophils incubated in culture supernatants increased their C3b receptors continuously for up to 4 hr, the longest interval tested. The effect of the culture supernatant was lost with dilution beyond eight- to 10-fold. The results suggest that culture supernatants of this long-term lymphoblastoid cell line contain soluble factors that induce increased expression of C3b receptors on PMN and may thus serve as a model for study of important physiologic effects of lymphocyte products on PMN in vivo. PMID:6230308

  18. [Inhibition of adherence of Corynebacterium diphtheriae to human buccal epithelium by glycoside hydrolases from marine hydrobiontes].

    PubMed

    Zaporozhets, T S; Makarenkova, I D; Bakunina, I Iu; Burtseva, Iu V; Kusaĭkin, M I; Balabanova, L A; Zviagintseva, T N; Besednova, N N; Rasskazov, V A

    2010-01-01

    A possibility of adhesion inhibition of Corynebacterium diphtheriae to human buccal epithelium by glycoside hydrolases of marine hydrobiontes was investigated using alpha-galactosidase from marine bacterium Pseudoalteromonas sp. KMM 701, total enzyme preparation and beta-1,3-glucanase from marine fungi Chaetomium, total enzyme preparation and beta-1,3-glucanase from marine mollusk Littorina kurila, and total enzyme preparation from crystalline style of marine mollusk Spisula sachalinensis were used. The enzymes were added to test-tubes containing buccal epithelial cells and/or the toxigenic bacterial strain C. diphtheriae No 1129, v. gravis. All the investigated enzymes were able to abort C. diphtheriae adherence, to human buccal epithelocytes. Inhibition of adhesion was more pronounced in the case of treatment of epithelocytes with highly purified enzymes of marine hydrobiontes in comparison with total enzyme preparations. The significant inhibition of C. diphtheriae adhesion was observed when the enzymes were added to the epithelocytes with the attached microorganisms. The results obtained show that glycoside hydrolases of marine hydrobiontes degrade any carbohydrates expressed on cell surface of bacterium or human buccal epithelocytes, impair unique lectin-carbohydrate interaction and prevent the adhesion. PMID:20695214

  19. Transplantation of human umbilical cord blood-derived adherent progenitors into the developing rodent brain.

    PubMed

    Coenen, Martin; Kögler, Gesine; Wernet, Peter; Brüstle, Oliver

    2005-08-01

    The results of several recent studies suggest that human umbilical cord blood (HUCB)-derived cells have the potential to undergo neural differentiation both in vitro and in vivo. Transplantation into the embryonic ventricular zone provides a unique opportunity to study the migration and differentiation of nonneural somatic progenitor cells in response to instructive cues within the developing neuroepithelium. We isolated an adherently growing population of HUCB-derived cells expressing CD13, CD29, CD49e, CD71, CD73, CD166, Flk-1, and vimentin but lacking CD34 and CD45. On transplantation into the ventricles of embryonic day 16.5 rat embryos, these cells formed subventricular clusters that extended into a variety of host brain regions, including striatum, cortex, hippocampus, thalamus, hypothalamus, tectum, pons, and cerebellum. Donor cells identified with an antibody to human nuclei or human-specific DNA in situ hybridization maintained expression of their original marker antigens and showed no expression of the neural markers MAP2 and NeuN (neurons), GFAP (astrocytes), and CNP (oligodendrocytes). In contrast to grafted primary neural cells, they remained largely confined to subventricular clusters with little evidence for intraparenchymal integration. Thus, the neurogenic environment of the embryonic ventricular zone does not promote the elaboration of a neural phenotype in HUCB-derived cells. PMID:16106216

  20. Anti-inflammatory effects of the partially purified extract of radix Stephaniae tetrandrae: comparative studies of its active principles tetrandrine and fangchinoline on human polymorphonuclear leukocyte functions.

    PubMed

    Shen, Y C; Chou, C J; Chiou, W F; Chen, C F

    2001-11-01

    We hypothesized that prevention of neutrophil from activation may underlie the myocardial protective effect of the specially processed extract of radix Stephaniae tetrandrae (SPRST). Inflammatory responses in isolated peripheral human neutrophils were studied in the presence or absence of SPRST. SPRST (1-10 microg/ml) concentration-dependently prevented N-formyl-methionyl-leucyl-phenylalanine (fMLP)- or leukotriene B(4) (LTB(4))-induced neutrophil adhesion and transmigration. Comparable results were also observed in neutrophils pretreated with fangchinoline (Fan) or tetrandrine (Tet), two active components in SPRST. It has been reported that neutrophil adhesion/transmigration is mainly Mac-1 (CD11b/CD18)-dependent and could be modulated by reactive oxygen species (ROS) production. SPRST, Tet, and Fan diminished fMLP- or LTB4-induced Mac-1 up-regulation and ROS production. SPRST, Fan, Tet, and verapamil impaired fMLP-induced rapid intracellular alkalization, an essential mechanism for neutrophil ROS production, and [Ca(2+)](i) increment, suggesting that a calcium dependent pathway might be involved. Direct G protein activation by AlF(4)(-) also triggered [Ca(2+)](i) increment and adhesion that could be abolished by pertussis toxin and were partially reversed by SPRST, Fan, and Tet. These results reveal that inhibition of neutrophil adhesion and transmigration may account for SPRST's myocardial protective effect. This effect of SPRST may be mediated by component(s) in addition to Tet and Fan because combination of 0.1 microg/ml of Tet and Fan did not mimic the effect of SPRST. We conclude that SPRST exerts anti-inflammatory effects by interfering with ROS production and Ca(2+) influx through G protein modulation to prevent Mac-1 up-regulation in neutrophil activation. PMID:11641437

  1. Fimbria-mediated adherence of Candida albicans to glycosphingolipid receptors on human buccal epithelial cells.

    PubMed Central

    Yu, L; Lee, K K; Sheth, H B; Lane-Bell, P; Srivastava, G; Hindsgaul, O; Paranchych, W; Hodges, R S; Irvin, R T

    1994-01-01

    Candida albicans is an opportunist fungal pathogen that has the ability to adhere to host cell surface receptors via a number of adhesins. Yu et al. (L. Yu, K. K. Lee, K. Ens, P. C. Doig, M. R. Carpenter, W. Staddon, R. S. Hodges, W. Paranchych, and R. T. Irvin, Infect. Immun. 62:2834-2842, 1994) described the purification and initial characterization of a fimbrial adhesin from C. albicans. In this paper, we show that C. albicans fimbriae also bind to asialo-GM1 [gangliotetraosylceramide: beta Gal(1-3)beta GalNAc(1-4) beta Gal(1-4)beta Glc(1-1)Cer] immobilized on microtiter plates in a saturable and concentration-dependent manner. C. albicans fimbrial binding to exfoliated human buccal epithelial cells (BECs) was inhibited by asialo-GM1 in in vitro binding assays. The fimbriae interact with the glycosphingolipid receptors via the carbohydrate portion of the receptors, since fimbriae were observed to bind to synthetic beta GalNAc(1-4)beta Gal-protein conjugates and the disaccharide was able to inhibit binding of fimbriae to BECs in in vitro binding assays. We conclude from these results that the C. albicans yeast form expresses a fimbrial adhesin that binds to glycosphingolipids displayed on the surface of human BECs. Images PMID:8005674

  2. Purification of myeloperoxidase from equine polymorphonuclear leucocytes.

    PubMed Central

    Mathy-Hartert, M; Bourgeois, E; Grülke, S; Deby-Dupont, G; Caudron, I; Deby, C; Lamy, M; Serteyn, D

    1998-01-01

    Increases of plasma concentrations of neutrophil myeloperoxidase (MPO) can be used as markers of polymorphonuclear leucocytes (PMN) activation in pathological situations (sepsis, acute lung injury, acute inflammation). To develop an assay for measurement of plasma MPO in horses during the above-mentioned infectious and inflammatory conditions, MPO was purified from equine PMN isolated from blood anticoagulated with citrate. PMN were extracted in a saline milieu (0.2 M Na acetate, 1 M NaCl, pH 4.7) to eliminate most of cellular proteins. Pellets were then extracted in the same buffer containing cationic detergent (1% cetyltrimethyl ammonium bromide). The supernatant was further purified by ion exchange chromatography (Hiload S Sepharose HP column 0.5 x 26 cm, equilibrated with 25 mM Na acetate, 0.2 M NaCl, pH 4.7) with a NaCl gradient (until 1 M). Most of the peroxidase activity of MPO (spectrophotometrically measured by the oxidation of orthodianisidine by hydrogen peroxide) was eluted at 0.65 M NaCl. MPO was further purified by gel filtration chromatography (Sephacryl S 200 column 2.6 x 42 cm with 25 mM Na acetate, 0.2 M NaCl, pH 4.7). MPO (specific activity: 74.3 U/mg) was obtained with a yield of 30% from the detergent extraction supernatant. Electrophoresis (non-reducing conditions) showed 3 bands identified, by comparison with human MPO, (i) the mature tetrameric enzyme (150 kDa) with 2 light and 2 heavy subunits, (ii) the precursor form (88 kDa) and (iii) a form of the heavy subunit without the prosthetic heme group (40 kDa). The mature enzyme and its precursor were glycosylated and possessed peroxidase activity. Equine MPO showed strong similarities with human and bovine MPO, with an absorption peak at 430 nm (Soret peak) characteristic of ferrimyeloperoxidase. Enzymatic activity was pH dependent (optimal value at pH 5.5). Images Figure 1. PMID:9553712

  3. Analysis of Endothelial Adherence of Bartonella henselae and Acinetobacter baumannii Using a Dynamic Human Ex Vivo Infection Model

    PubMed Central

    Weidensdorfer, Marko; Chae, Ju Ik; Makobe, Celestine; Stahl, Julia; Averhoff, Beate; Müller, Volker; Schürmann, Christoph; Brandes, Ralf P.; Wilharm, Gottfried; Ballhorn, Wibke; Christ, Sara; Linke, Dirk; Fischer, Doris; Göttig, Stephan

    2015-01-01

    Bacterial adherence determines the virulence of many human-pathogenic bacteria. Experimental approaches elucidating this early infection event in greater detail have been performed using mainly methods of cellular microbiology. However, in vitro infections of cell monolayers reflect the in vivo situation only partially, and animal infection models are not available for many human-pathogenic bacteria. Therefore, ex vivo infection of human organs might represent an attractive method to overcome these limitations. We infected whole human umbilical cords ex vivo with Bartonella henselae or Acinetobacter baumannii under dynamic flow conditions mimicking the in vivo infection situation of human endothelium. For this purpose, methods for quantifying endothelium-adherent wild-type and trimeric autotransporter adhesin (TAA)-deficient bacteria were set up. Data revealed that (i) A. baumannii binds in a TAA-dependent manner to endothelial cells, (ii) this organ infection model led to highly reproducible adherence rates, and furthermore, (iii) this model allowed to dissect the biological function of TAAs in the natural course of human infections. These findings indicate that infection models using ex vivo human tissue samples (“organ microbiology”) might be a valuable tool in analyzing bacterial pathogenicity with the capacity to replace animal infection models at least partially. PMID:26712205

  4. Platelet activating factor amplifies human neutrophil adherence to bovine endothelial cells: evidence for a lipoxygenase dependent mechanism.

    PubMed

    Damtew, B; Spagnuolo, P J

    1992-10-01

    Platelet activating factor (PAF) is a potent lipid mediator that induces the release of leukotrienes and prostaglandins from various cells and tissues. We examined the capacity of PAF alone and in combination with soluble stimuli to enhance eicosanoid synthesis and adherence of human neutrophils. Neutrophils were preincubated with PAF and washed before exposure to the soluble stimuli F-Met-Leu-Phe (FMLP), calcium ionophore A23187, and phorbol myristate acetate. Preincubation of neutrophils with 1 microM PAF enhanced the release of both LTB4 and LTC4 in response to each of the three agonists, in contrast with the unprimed neutrophils. Priming was specific for PAF since lyso-PAF was inactive. Priming concentrations of PAF also augmented the adherence of neutrophils to endothelium in the presence of the soluble agonists A23187, phorbol myristate acetate, and FMLP. The priming effect of PAF on eicosanoid release and neutrophil adherence was shown to have similar time- and dose-dependent effects. Further, the priming effects of PAF on adherence could be reversed by preincubation of neutrophils with the lipoxygenase inhibitors nordihydroguiaretic acid and 5,8,11,14-ETYA but not by preincubation with the cyclooxygenase inhibitor indomethacin. These data demonstrate that PAF amplifies neutrophil adherence to endothelium through a lipoxygenase dependent mechanism. PMID:1330924

  5. Effect of antiarrhythmic drugs on In-111-labeled leukocytes: chemotaxis and adherence to nylon wool

    SciTech Connect

    Thakur, M.L.; Walsh, L.J.; Zaret, B.L.; Gottschalk, A.

    1982-02-01

    The influence of lidocaine (L) and procainamide (P) on the chemotactic ability and adherence to nylon wool of In-111-labeled human polymorphonuclear leukocytes (PMNs) was investigated. At the normal therapeutic levels of L (0.022 mM whole blood) or P (0.03 mM whole blood) no change in PMN function was observed. However, at and above five times the aforementioned blood levels of L, significant reduction in the chemotactic ability of PMNs was noted (p less than 0.005). The adverse effects of In-111 radiation appeared insignificant at all L or P concentrations during the 3-hr observation period. The labeled PMNs were resistant to the toxic effects of a higher concentration of P than that of L, and the reduction in PMN chemotaxis and adherence to nylon wool was not apparent until the P concentration reached 1.5 mM.

  6. Role of specific determinants in mannan of Candida albicans serotype A in adherence to human buccal epithelial cells.

    PubMed Central

    Miyakawa, Y; Kuribayashi, T; Kagaya, K; Suzuki, M; Nakase, T; Fukazawa, Y

    1992-01-01

    Candida albicans serotype A (C. albicans A) possesses a specific antigen, designated antigen 6, which resides in mannans on the cell surface. To determine the role of the mannan moiety of the C. albicans cell wall in adherence to buccal epithelial cells, we used antigen 6-deficient mutants which had been isolated by screening with an agglutinating monoclonal antibody against antigen 6 (MAb-6). 1H nuclear magnetic resonance spectral analysis of the purified mannans from the mutants showed a loss of the signals related to that beta-linkage of the side chains. Moreover, acetolyzed fragments of the mutant mannans showed a decreased amount of mannohexaose and mannopentaose. The mutant yeast cells exhibited significantly reduced ability to adhere both to exfoliated buccal epithelial cells and to a human buccal cell line. A number of strains of C. albicans A, C. tropicalis, and C. glabrata, all of which bear antigen 6, showed significantly higher adherence to the cell line than did those of C. albicans serotype B, which lack antigen 6. The whole mannan from the C. albicans A parent inhibited the adherence of C. albicans A to epithelial cells dose dependently, whereas mannan from a mutant strains did not. Moreover, C. albicans A treated with MAb-6 or polyclonal factor 6 serum showed reduced adherence. A close correlation was found between adhesive ability and agglutinability with MAb-6 in the C. albicans A parent, the antigenic mutants, and their spontaneous revertants. These results suggest that so far as mannan adhesion is concerned, serotype A-specific determinants are largely involved in the mechanisms of adherence of C. albicans A to human buccal epithelial cells. PMID:1375200

  7. Inhibitory effect of salmeterol on the respiratory burst of adherent human neutrophils.

    PubMed

    Ottonello, L; Morone, P; Dapino, P; Dallegri, F

    1996-10-01

    Human neutrophils, plated in fibronectin-coated wells and stimulated with N-formyl-methionylleucyl-phenylalanine (fMLP), were found to undergo a massive and prolonged respiratory burst, as measured by monitoring superoxide production. The beta 2-agonist salmeterol inhibited the respiratory burst in a dose-dependent manner. In contrast, salbutamol was ineffective. Moreover, the neutrophil respiratory burst was partially suppressed by prostaglandin E2 (PGE2) and the phosphodiesterase type IV (PDE-IV) inhibitor RO 20-1724. When salmeterol was used in combination with PGE2 or RO 20-1724, additive inhibitory effects were observed. The inhibitory activity of salmeterol was not reversed in the presence of the beta-blocker propranolol, and did not correlate with its ability of increasing cyclic AMP (cAMP) levels. Finally, the compounds used did not affect neutrophil adherence to fibronectin-coated wells. The results suggest that salmeterol is capable of down-regulating the neutrophil oxidative response to fMLP, also of co-operating with PGE2 and PDE-IV inhibitor RO 20-1724 in a manner not related to its beta 2-receptor binding activity. In other words, salmeterol displays neutrophil-directed effects, susceptible to be amplified by natural mediators such as PGE2 or PDE-IV inhibitors, consistent with possible anti-inflammatory properties of the drug. PMID:8870705

  8. Inhibitory effect of salmeterol on the respiratory burst of adherent human neutrophils

    PubMed Central

    OTTONELLO, L; MORONE, P; DAPINO, P; DALLEGRI, F

    1996-01-01

    Human neutrophils, plated in fibronectin-coated wells and stimulated with n-formyl-methionyl-leucyl-phenylalanine (fMLP), were found to undergo a massive and prolonged respiratory burst, as measured by monitoring superoxide production. The β2-agonist salmeterol inhibited the respiratory burst in a dose-dependent manner. In contrast, salbutamol was ineffective. Moreover, the neutrophil respiratory burst was partially suppressed by prostaglandin E2 (PGE2) and the phosphodiesterase type IV (PDE-IV) inhibitor RO 20-1724. When salmeterol was used in combination with PGE2 or RO 20-1724, additive inhibitory effects were observed. The inhibitory activity of salmeterol was not reversed in the presence of the β-blocker propranolol, and did not correlate with its ability of increasing cyclic AMP (cAMP) levels. Finally, the compounds used did not affect neutrophil adherence to fibronectin-coated wells. The results suggest that salmeterol is capable of down-regulating the neutrophil oxidative response to fMLP, also of co-operating with PGE2 and PDE-IV inhibitor RO 20-1724 in a manner not related to its β2-receptor binding activity. In other words, salmeterol displays neutrophil-directed effects, susceptible to be amplified by natural mediators such as PGE2 or PDE-IV inhibitors, consistent with possible anti-inflammatory properties of the drug. PMID:8870705

  9. Attachment role of gonococcal pili. Optimum conditions and quantitation of adherence of isolated pili to human cells in vitro.

    PubMed Central

    Pearce, W A; Buchanan, T M

    1978-01-01

    Gonoccocal pili facilitate attachment of virulent Neisseria gonorrhoeae to human cells. To characterize this attachment function, purified gonococcal pili isolated from four strains possessing antigenically distinct pili were radiolabeled with 125I and used to measure the attachment of pili to various human cells in vitro. Human buccal and cervical-vaginal mucosal epithealial cells, fallopian tube mucosa, and sperm bound pili in greater numbers per micrometer2 of surface area (1--10) than fetal tonsil fibroblasts, HeLa M cells, erythrocytes, or polymorphonuclear leukocytes. This cell specificity of attachment suggests a greater density of membrane pili binding sites on cells similar or identical to cells from natural sites of infection. The pili binding sites were quantitated as 1 X 10(4) per cervical-vaginal squamous cell. Pili of all antigenic types attached equally to a given cell type, implying that the attachment moiety of each pilus was similar. Attachement of gonoccocal pili to human cells occurred quickly with saturation of presumed receptor sites within 20--60 min. Attachment was temperature dependent (37 degrees greater than 20 degrees greater than 4 degrees C), and pH dependent (3.5 less than 4.5 less than 5.5 less than 7.5). Attachment was inhibited by antibody to pili (homologous pili Ab greater than heterologous Ab). The extent of possible protection against gonococcal infection due to inhibition of pili-mediated attachment might prove limited as a result of the considerable antigenic heterogeneity among pili and the observation that blockage of pili attachment is maximal only with antibody to pili of the infecting strain. Images PMID:96134

  10. Hepatitis B virus efficiently infects non-adherent hepatoma cells via human sodium taurocholate cotransporting polypeptide

    PubMed Central

    Okuyama-Dobashi, Kaori; Kasai, Hirotake; Tanaka, Tomohisa; Yamashita, Atsuya; Yasumoto, Jun; Chen, Wenjia; Okamoto, Toru; Maekawa, Shinya; Watashi, Koichi; Wakita, Takaji; Ryo, Akihide; Suzuki, Tetsuro; Matsuura, Yoshiharu; Enomoto, Nobuyuki; Moriishi, Kohji

    2015-01-01

    Sodium taurocholate cotransporting polypeptide (NTCP) has been reported as a functional receptor for hepatitis B virus (HBV) infection. However, HBV could not efficiently infect HepG2 cells expressing NTCP (NTCP-HepG2 cells) under adherent monolayer-cell conditions. In this study, NTCP was mainly detected in the basolateral membrane region, but not the apical site, of monolayer NTCP-HepG2 cells. We hypothesized that non-adherent cell conditions of infection would enhance HBV infectivity. Non-adherent NTCP-HepG2 cells were prepared by treatment with trypsin and EDTA, which did not degrade NTCP in the membrane fraction. HBV successfully infected NTCP-HepG2 cells at a viral dose 10 times lower in non-adherent phase than in adherent phase. Efficient infection of non-adherent NTCP-HepG2 cells with blood-borne or cell-culture-derived HBV was observed and was remarkably impaired in the presence of the myristoylated preS1 peptide. HBV could also efficiently infect HepaRG cells under non-adherent cell conditions. We screened several compounds using our culture system and identified proscillaridin A as a potent anti-HBV agent with an IC50 value of 7.2 nM. In conclusion, non-adherent host cell conditions of infection augmented HBV infectivity in an NTCP-dependent manner, thus providing a novel strategy to identify anti-HBV drugs and investigate the mechanism of HBV infection. PMID:26592202

  11. Adherence of Candida albicans to human buccal epithelial cells: host-induced protein synthesis and signaling events.

    PubMed Central

    Bailey, A; Wadsworth, E; Calderone, R

    1995-01-01

    The synthesis of proteins by Candida albicans was studied following adherence of blastoconidia to human buccal epithelial cells (HBEC). Initially, labeling of HBEC, C. albicans, and HBEC-C. albicans with [35S]methionine was performed. After a 3-h incubation and prior to labeling with [35S]methionine, the cultures were treated with cycloheximide to prevent HBEC protein synthesis. The HBEC-C. albicans mixture as well as C. albicans and HBEC incubated separately were extracted with beta-mercaptoethanol (beta-ME). These extracts as well as the cell residue (solubilized by boiling with sodium dodecyl sulfate [SDS]) were examined by SDS-polyacrylamide gel electrophoresis and autoradiography. In comparison to cultures of C. albicans incubated without HBEC, proteins with molecular masses of approximately 52 to 56 kDa from beta-ME extracts and from SDS-solubilized cells were observed only from adhering cultures. In addition, unlabeled beta-ME extracts were electrotransferred to nitrocellulose and immunoblotted with antiphosphotyrosine antibodies to determine whether cell signaling events were occurring during adherence. Proteins with molecular masses of 54 and 60 kDa were recognized only in mixed cultures of C. albicans and HBEC. These data indicate that following adherence of C. albicans to HBEC, new Candida proteins are expressed. Further, these events are accompanied by the expression of signal proteins, presumably of Candida origin. PMID:7822023

  12. Human Cardiac-Derived Adherent Proliferating Cells Reduce Murine Acute Coxsackievirus B3-Induced Myocarditis

    PubMed Central

    Miteva, Kapka; Haag, Marion; Peng, Jun; Savvatis, Kostas; Becher, Peter Moritz; Seifert, Martina; Warstat, Katrin; Westermann, Dirk; Ringe, Jochen; Sittinger, Michael; Schultheiss, Heinz-Peter

    2011-01-01

    Background Under conventional heart failure therapy, inflammatory cardiomyopathy typically has a progressive course, indicating a need for alternative therapeutic strategies to improve long-term outcomes. We recently isolated and identified novel cardiac-derived cells from human cardiac biopsies: cardiac-derived adherent proliferating cells (CAPs). They have similarities with mesenchymal stromal cells, which are known for their anti-apoptotic and immunomodulatory properties. We explored whether CAPs application could be a novel strategy to improve acute Coxsackievirus B3 (CVB3)-induced myocarditis. Methodology/Principal Findings To evaluate the safety of our approach, we first analyzed the expression of the coxsackie- and adenovirus receptor (CAR) and the co-receptor CD55 on CAPs, which are both required for effective CVB3 infectivity. We could demonstrate that CAPs only minimally express both receptors, which translates to minimal CVB3 copy numbers, and without viral particle release after CVB3 infection. Co-culture of CAPs with CVB3-infected HL-1 cardiomyocytes resulted in a reduction of CVB3-induced HL-1 apoptosis and viral progeny release. In addition, CAPs reduced CD4 and CD8 T cell proliferation. All CAPs-mediated protective effects were nitric oxide- and interleukin-10-dependent and required interferon-γ. In an acute murine model of CVB3-induced myocarditis, application of CAPs led to a decrease of cardiac apoptosis, cardiac CVB3 viral load and improved left ventricular contractility parameters. This was associated with a decline in cardiac mononuclear cell activity, an increase in T regulatory cells and T cell apoptosis, and an increase in left ventricular interleukin-10 and interferon-γ mRNA expression. Conclusions We conclude that CAPs are a unique type of cardiac-derived cells and promising tools to improve acute CVB3-induced myocarditis. PMID:22174827

  13. Human placenta-derived adherent cells improve cardiac performance in mice with chronic heart failure.

    PubMed

    Chen, Hong-Jung; Chen, Chien-Hsi; Chang, Ming-Yao; Tsai, Da-Ching; Baum, Ellen Z; Hariri, Robert; Herzberg, Uri; Hsieh, Patrick C H

    2015-03-01

    Human placenta-derived adherent cells (PDACs) are a culture-expanded, undifferentiated mesenchymal-like population derived from full-term placental tissue, with immunomodulatory, anti-inflammatory, angiogenic, and neuroprotective properties. PDA-001 (cenplacel-L), an intravenous formulation of PDAC cells, is in clinical development for the treatment of autoimmune and inflammatory diseases. We tested the therapeutic effects of PDA-001 in mice with chronic heart failure (CHF). Three weeks after transaortic constriction surgery to induce CHF, the mice underwent direct intramyocardial (IM) or i.v. injection of PDA-001 at a high (0.5 × 10(6) cells per mouse), medium (0.5 × 10(5) cells per mouse), or low (0.5 × 10(4) cells per mouse) dose. The mice were sacrificed 4 weeks after treatment. Echocardiography and ventricular catheterization showed that IM injection of PDA-001 significantly improved left ventricular systolic and diastolic function compared with injection of vehicle or i.v. injection of PDA-001. IM injection of PDA-001 also decreased cardiac fibrosis, shown by trichrome staining in the vicinity of the injection sites. Low-dose treatment showed the best improvement in cardiac performance compared with the medium- and high-dose groups. In another independent study to determine the mechanism of action with bromodeoxyuridine labeling, the proliferation rates of endothelial cells and cardiomyocytes were significantly increased by low or medium IM dose PDA-001. However, no surviving PDA-001 cells were detected in the heart 1 month after injection. In vivo real-time imaging consistently revealed that the PDA-001 cells were detectable only within 2 days after IM injection of luciferase-expressing PDA-001. Together, these results have demonstrated the cardiac therapeutic potential of PDA-001, likely through a paracrine effect. PMID:25673767

  14. Late Adherent Human Bone Marrow Stromal Cells Form Bone and Restore the Hematopoietic Microenvironment In Vivo

    PubMed Central

    Vianna, Verônica Fernandes; Bonfim, Danielle Cabral; Cavalcanti, Amanda dos Santos; Fernandes, Marco Cury; Kahn, Suzana Assad; Casado, Priscila Ladeira; Lima, Inayá Correa; Murray, Samuel S.; Murray, Elsa J. Brochmann; Duarte, Maria Eugenia Leite

    2013-01-01

    Bone marrow stromal cells (BMSCs) are a valuable resource for skeletal regenerative medicine because of their osteogenic potential. In spite of the very general term “stem cell,” this population of cells is far from homogeneous, and different BMSCs clones have greatly different phenotypic properties and, therefore, potentially different therapeutic potential. Adherence to a culture flask surface is a primary defining characteristic of BMSCs. We hypothesized that based on the adherence time we could obtain an enriched population of cells with a greater therapeutic potential. We characterized two populations of bone marrow-derived cells, those that adhered by three days (R-cells) and those that did not adhere by three days but did by six days (L-cells). Clones derived from L-cells could be induced into adipogenic, chondrogenic, and osteogenic differentiation in vitro. L-cells appeared to have greater proliferative capacity, as manifested by larger colony diameter and clones with higher CD146 expression. Only clones from L-cells developed bone marrow stroma in vivo. We conclude that the use of late adherence of BMSCs is one parameter that can be used to enrich for cells that will constitute a superior final product for cell therapy in orthopedics. PMID:23710460

  15. Adherence to antiretrovirals in people coinfected with the human immunodeficiency virus and tuberculosis1

    PubMed Central

    Lemos, Larissa de Araújo; Fiuza, Maria Luciana Teles; Reis, Renata Karina; Ferrer, André Carvalho; Gir, Elucir; Galvão, Marli Teresinha Gimeniz

    2016-01-01

    Objective: assess the adherence levels to antiretroviral therapy in people coinfected with HIV/tuberculosis and correlate these levels with the sociodemographic and clinical variables of the study population. Method: cross-sectional study involving 74 male and female adults coinfected with HIV/tuberculosis. For the data collection, a sociodemographic and clinical assessment form and the Antiretroviral Treatment Adherence Assessment Questionnaire were used. For the data analysis, the software STATA version 11 was used, through descriptive statistics, Fisher's chi-square exact test and the probability test. Results: men were predominant (79.7%), between 30 and 39 years of age (35.1%), low income (75.7%) and pulmonary tuberculosis (71.6%). Adherence to antiretroviral therapy was inappropriate in 78.1% of the men; 61.0% of single people; 47.0% unemployed and 76.5% among people gaining less than one minimum wage. A significant difference was observed between compliance and length of use of antiretrovirals (p=0.018), sexual orientation (p=0.024) and number of children (p=0.029). Conclusion: the coinfected patients presented inappropriate adherence to the antiretrovirals, a fact that negatively affects the health conditions of the people living with HIV/tuberculosis coinfection. A statistically significant correlation was found between the levels of adherence and some sociodemographic and clinical characteristics. PMID:27192416

  16. Effects of eugenol on polymorphonuclear cell migration and chemiluminescence.

    PubMed

    Fotos, P G; Woolverton, C J; Van Dyke, K; Powell, R L

    1987-03-01

    In this study, the effects of eugenol on human polymorphonuclear (PMN) cell migration and chemiluminescence were examined in vitro. Utilizing zymosan-activated serum or crude Bacteroides sonicate fractions as chemotractants, we found that eugenol inhibits PMN migration at 6.6 X 10(-2) to 6.6 X 10(-5) mol/L (P less than 0.05). Also, similar effects were observed in PMNs pre-incubated in eugenol. Regardless of concentration, eugenol was not found to induce chemotaxis of PMNs. An examination of PMN membrane activation through chemiluminescence gave results consistent with the chemotaxis data, demonstrating a decrease in light emission at concentrations as low as 6.6 X 10(-6) mol/L (P less than 0.05). In view of these data, the potential effect of eugenol on in vivo (sulcular or periapical) PMN function deserves further study. PMID:3475310

  17. Enzymatic treatment of long-term human marrow cultures reveals the preferential location of primitive hemopoietic progenitors in the adherent layer.

    PubMed

    Coulombel, L; Eaves, A C; Eaves, C J

    1983-08-01

    Recent studies with long-term mouse marrow cultures have indicated the importance of the adherent layer as a primary reservoir of the most primitive stem cells, from which derivative stem cells and more differentiated progenitors are continuously generated. We have now examined the role of the adherent cell layer in long-term human marrow cultures from this point of view. Prerequisite to such an undertaking was the development of a nontoxic and reproducible method for detaching the adherent layer and making it into a single-cell suspension suitable for characterization by colony assays. Both trypsin and collagenase could be used to obtain suspensions that met these criteria. Lack of toxicity was demonstrated by the preservation of CFU-E, BFU-E, and CFU-C plating efficiency in fresh human marrow cell suspensions exposed to the same enzymatic treatments. Collagenase treatment of long-term marrow culture adherent layers was considered superior because it freed all hemopoietic colony-forming cells but left some of the other cells still adherent. Using this method, we found that CFU-C, BFU-E, and CFU-G/E were consistently detectable in the adherent layer for at least 8 wk, with the majority of the BFU-E and CFU-G/E being located in the adherent layer (70%-75% after 2-3 wk and more than 90% by 7-8 wk). Although corresponding numerical differences in adherent and nonadherent CFU-C populations were not observed, the colonies derived from them showed marked differences in the size they achieved; the adherent layer being the exclusive site of CFU-C, with a very high proliferative capacity. These findings emphasize the importance of assessing the progenitor content of the adherent layer of long-term human marrow cultures and provide an appropriate methodology. PMID:6307430

  18. EX VIVO ADHERENCE TO MURINE ILEAL, BIOFILM FORMATION ABILITY AND PRESENCE OF ADHERENCE-ASSOCIATED OF HUMAN AND ANIMAL DIARRHEAGENIC ESCHERICHIA COLI.

    PubMed

    Sukkua, Kannika; Rattanachuay, Pattamarat; Sukhumungoon, Pharanai

    2016-01-01

    Diarrheagenic Escherichia coli (DEC) are important bacteria causing gastrointestinal infection, which can lead to severe forms of illnesses. This study focused on DEC adherent capabilities using murine intestinal tissue as a model. Ex vivo adherence results showed that enteroaggregative E. coli (EAEC) strain PSU280 exhibited the highest level of adherence, followed by strains from ETEC category. Scanning electron micrographs displayed tight binding and putative bacterial curli fibers, including putative fimbrial structures. The presence of putative curli fibers was confirmed by the presence of csgA, a curli major structural subunit gene. Five and 3 of 15 DEC possessed lpf (encoding long polar fimbriae) and agn43 (encoding antigen43), respectively. Comparable biofilm formation efficiency but variable levels autoaggregation were observed among the DEC strains. In addition, yeast agglutination could be visualized in 11/15 strains. This study demonstrates the adherent ability of DEC strains isolated in southern Thailand as well as a number of crucial adherence-associated genes, information of importance to the understanding of DEC pathogenesis in this region of the country. PMID:27086424

  19. Human podocytes adhere to the KRGDS motif of the alpha3alpha4alpha5 collagen IV network.

    PubMed

    Borza, Corina M; Borza, Dorin-Bogdan; Pedchenko, Vadim; Saleem, Moin A; Mathieson, Peter W; Sado, Yoshikazu; Hudson, Heather M; Pozzi, Ambra; Saus, Juan; Abrahamson, Dale R; Zent, Roy; Hudson, Billy G

    2008-04-01

    Podocyte adhesion to the glomerular basement membrane is required for proper function of the glomerular filtration barrier. However, the mechanism whereby podocytes adhere to collagen IV networks, a major component of the glomerular basement membrane, is poorly understood. The predominant collagen IV network is composed of triple helical protomers containing the alpha3alpha4alpha5 chains. The protomers connect via the trimeric noncollagenous (NC1) domains to form hexamers at the interface. Because the NC1 domains of this network can potentially support integrin-dependent cell adhesion, it was determined whether individual NC1 monomers or alpha3alpha4alpha5 hexamers support podocyte adhesion. It was found that, although human podocytes did not adhere to NC1 domains proper, they did adhere via integrin alphavbeta3 to a KRGDS motif located adjacent to alpha3NC1 domains. Because the KRGDS motif is a site of phosphorylation, its interactions with integrin alphavbeta3 may play a critical role in cell signaling in physiologic and pathologic states. PMID:18235087

  20. Butyrate modulates bacterial adherence on LS174T human colorectal cells by stimulating mucin secretion and MAPK signaling pathway

    PubMed Central

    Jung, Tae-Hwan; Park, Jeong Hyeon; Han, Kyoung-Sik

    2015-01-01

    BACKGROUND/OBJECTIVES Fermentation of dietary fiber results in production of various short chain fatty acids in the colon. In particular, butyrate is reported to regulate the physical and functional integrity of the normal colonic mucosa by altering mucin gene expression or the number of goblet cells. The objective of this study was to investigate whether butyrate modulates mucin secretion in LS174T human colorectal cells, thereby influencing the adhesion of probiotics such as Lactobacillus and Bifidobacterium strains and subsequently inhibiting pathogenic bacteria such as E. coli. In addition, possible signaling pathways involved in mucin gene regulation induced by butyrate treatment were also investigated. MATERIALS/METHODS Mucin protein content assay and periodic acid-Schiff (PAS) staining were performed in LS174T cells treated with butyrate at various concentrations. Effects of butyrate on the ability of probiotics to adhere to LS174T cells and their competition with E. coli strains were examined. Real time polymerase chain reaction for mucin gene expression and Taqman array 96-well fast plate-based pathway analysis were performed on butyrate-treated LS174T cells. RESULTS Treatment with butyrate resulted in a dose-dependent increase in mucin protein contents in LS174T cells with peak effects at 6 or 9 mM, which was further confirmed by PAS staining. Increase in mucin protein contents resulted in elevated adherence of probiotics, which subsequently reduced the adherent ability of E. coli. Treatment with butyrate also increased transcriptional levels of MUC3, MUC4, and MUC12, which was accompanied by higher gene expressions of signaling kinases and transcription factors involved in mitogen-activated protein kinase (MAPK) signaling pathways. CONCLUSIONS Based on our results, butyrate is an effective regulator of modulation of mucin protein production at the transcriptional and translational levels, resulting in changes in the adherence of gut microflora. Butyrate

  1. Alteration of rat polymorphonuclear leukocyte function after thermal injury.

    PubMed

    Gruber, D F; D'Alesandro, M M

    1989-01-01

    One portion of host defense to bacterial challenge(s) involves the activation and infiltration of endogenous polymorphonuclear leukocytes. Thermal injuries are frequently associated with immunologic abnormalities including alterations of polymorphonuclear leukocyte-associated nonspecific resistance. We examined isolated peripheral rat polymorphonuclear leukocytes for alterations in membrane potential, oxidative capability, and locomotor function after the experimental application of 20% full-thickness body surface area thermal injury. Thermal injury resulted in significant reductions of peripheral red blood cell concentration(s) and increases in leukocyte and platelet concentrations for 42 days after injury. In addition to the quantitative changes, polymorphonuclear leukocytes also demonstrated altered qualitative functions. Compared with phorbol myristate acetate-induced activation of normal cells, polymorphonuclear leukocyte membranes from thermal-injured animals were electrophysiologically less responsive for 3 weeks after injury. The ability of polymorphonuclear leukocytes to produce intracellular H2O2, a measure of oxidative function, was also significantly decreased for 7 days after injury. The paradox in this paradigm of thermal injury was the demonstration of peripheral polymorphonuclear leukocyte quantitative increases with concurrent significant qualitative impairment. Qualitative lesions included altered states of membrane depolarization and depressed oxidative capability that may individually, or collectively, reduce nonspecific immune capabilities of the host to levels that are inadequate to combat infection. PMID:2793916

  2. Biphasic control of polymorphonuclear cell migration by Kupffer cells. Effect of exposure to metabolic products of ethanol

    SciTech Connect

    Fainsilber, Z.; Feinman, L.; Shaw, S.; Lieber, C.S.

    1988-01-01

    In order to investigate the role of the Kupffer cells in the regulation of the inflammatory reaction seen in alcoholic hepatitis, rat liver Kupffer cells were cultured and exposed to products of ethanol metabolism. The resultant supernatants were tested to study their ability to stimulate or inhibit polymorphonuclear cell chemotaxis. Kupffer cells produced increased chemokinetic activity for human polymorphonuclear leukocytes; when incubated with soluble products of microsomal peroxidation, the Kupffer cells engendered more chemokinetic activity than that produced by untreated Kupffer cells. When Kupffer cells were incubated with acetaldehyde, the chemokinetic activity that appeared in the supernatant did not differ from control. Chemotaxis of polymorphonuclear cells was not observed when the Kupffer cell supernatants were tested by checkerboard analysis.

  3. Polymorphonuclear neutrophil function in systemic sclerosis.

    PubMed Central

    Czirják, L; Dankó, K; Sipka, S; Zeher, M; Szegedi, G

    1987-01-01

    In vitro functions of polymorphonuclear (PMN) neutrophils were studied in 20 patients with progressive systemic sclerosis (PSS). An increase in the basal chemiluminescence (CL) activity of peripheral blood PMNs was found, suggesting that these cells had been preactivated in vivo. Patients with more extensive skin disease or signs of disease progression tended to have higher basal CL values. Active oxygen products during the respiratory burst may increase the extent of inflammatory and fibrotic processes and could be involved in the endothelial injury in PSS. The stimulatory capacity of CL response was normal in our study. No alterations were found in the opsonised yeast phagocytic activity of granulocytes when compared with control values. The binding of erythrocyte-antibody particles was found also to be normal. A depressed chemotactic activity of PMN cells against zymosan activated serum was also shown. The cause of the decreased chemotaxis of PMNs remains to be elucidated. PMID:3592786

  4. Adherence of Legionella pneumophila to guinea pig peritoneal macrophages, J774 mouse macrophages, and undifferentiated U937 human monocytes: role of Fc and complement receptors.

    PubMed Central

    Husmann, L K; Johnson, W

    1992-01-01

    Legionella pneumophila, the causative agent of Legionnaires' disease, is a facultative intracellular pathogen of alveolar macrophages. Although previous studies have demonstrated that specific antibody facilitates uptake of L. pneumophila by phagocytic cells, the role of complement has been unclear. Thus, we have examined the relative contributions of Fc gamma- and complement receptor-mediated adherence to guinea pig peritoneal macrophages, U937 human monocytic cells, and J774 mouse macrophage cells. Opsonization of L. pneumophila (Philadelphia 2) with polyclonal immunoglobulin G promoted maximum adherence to guinea pig macrophages. In contrast, incubation in the presence of 20% fresh nonimmune human serum from a single donor did not promote adherence. The results obtained with U937 and J774 cells paralleled those obtained with guinea pig macrophages. In the absence of specific antibody, opsonization with guinea pig complement did not enhance adherence of the Philadelphia 1, Philadelphia 2, or Knoxville strain. However, when complement was added to heat-inactivated, specific antiserum, a fourfold increase in the number of adherent organisms was observed. Blocking studies utilizing membrane receptor-specific monoclonal antibodies demonstrated that both Fc and complement receptors mediated adherence of organisms treated with complement in the presence of specific antibody. These results suggest that complement augments adherence of L. pneumophila only when acting in concert with specific antibody. PMID:1452353

  5. New method to quantitate platelets adhered on biomaterials using monoclonal antibodies to human platelet membrane glycoprotein SZ-21

    SciTech Connect

    Xi, T.F.; Zhang, J.C.; Tian, W.H.; Wang, C.R.; Lei, X.H.; Wai, H.Y.; Ruan, C.G. )

    1990-01-01

    This study developed a new technique to quantitate platelets adhered on biomaterials surfaces in vitro, based on a surface phased radioimmunoassay using a monoclonal antibody SZ-21, directed specifically against the membrane glycoprotein complex IIIa of human platelets. In vitro perfusion is performed in system which consists of testing tubes and infusion pump. After 5 minutes perfusion with fresh ACD anticoagulated human whole blood at 2,000s-1 platelets deposition on surface precoated with proteins determined using anti-human platelet antibody (125 I-SZ-21) are 4,173 +/- 932 (Albumin), 59,032 +/- 25,554 (Fibrinogen), and 71,253 +/- 11,484 (Collagen). Meanwhile, platelets adhered on surfaces of four polymers were determined (platelet/mm2): 19,493 +/- 2,050 (Silicone), 48,193 +/- 4,055 (Polytetrafluoroethylene), 50,375 +/- 8,675 (Polyvinyl chloride) and 101,906 +/- 5,916 (Polyethylene). These results were confirmed by SEM. This method is not only applied for evaluating rapidly and reliably blood compatibility of biomaterials in vitro, but will be used at basic study for interaction of blood materials.

  6. The influence of some vegetable extracts on the in vitro adherence of mouse and human lymphocytes to nylon fibers.

    PubMed

    Lenghel, V; Radu, D L; Chirilă, P; Olinescu, A

    1995-01-01

    We found that the total watery extracts obtained from roots of various plants such as Symphytum officinale, Phytolacca americana etc, precipitate human glycoproteins, agglutinate sheep red blood cells (SRBC) and stimulate lymphocyte adherence to nylon fibers. Five out of seven extracts precipitated human gammaglobulins and one of seven obviously agglutinate SRBC. If these cells were pretreated with rabbit antibodies against SRBC, all extracts agglutinated the cells at various degrees of intensity, the most active being Phytolacca americana. The adherence of mouse but not human lymphocytes to nylon fibers was stimulated by extracts of Symphytum officinale and Phytolacca americana. This process was neither stimulated nor inhibited by Mannose (Man), Galactose (Gal), Glucose (Glc), N-acethyl Galactose (GalNAc) and N-acethyl Glucose (Glc-NAc). These biological effects of the plant extracts could be the expression of a lectin-like ability to bind various sugars other than those mentioned. The results suggest the possibility of using different extracts as means to point out the presence in serum or at the cellular level of some carbohydrates influencing the cellular adhesion, phenomenon which plays an important role in the functions of hematopoietic cells. PMID:8993111

  7. Adherence of Borrelia burgdorferi to granulocytes of different animal species.

    PubMed

    Grassmann, B; Kopp, P A; Schmitt, M; Blobel, H

    1997-04-01

    Adherence of 4 Borrelia (B.) burgdorferi strains (z7/22, z7/27, z7/41, PBi) to polymorphonuclear granulocytes from different domestic animals (horses, cattle, sheep, dogs) was investigated. All 4 strains adhered to the granulocytes. Binding assays indicated that the adherence occurred between structures on the surface of the borreliae ("binding-sites") and on the membranes of the granulocytes ("receptors"). The "receptors" consisted of 4 fractions (A, B, C, and D) with components differing in molecular weight (MW) and binding activity for proteins on the surface of B. burgdorferi. Fraction A (MW 80000) had the highest binding activity for B. burgdorferi. PMID:9144911

  8. Adhering heat-killed human Lactobacillus acidophilus, strain LB, inhibits the process of pathogenicity of diarrhoeagenic bacteria in cultured human intestinal cells.

    PubMed

    Coconnier, M H; Bernet, M F; Chauvière, G; Servin, A L

    1993-12-01

    Heat-killed L. acidophilus, strain LB, was tested for its ability to adhere in vitro onto human enterocyte-like Caco-2 and muco-secreting HT29-MTX cells in culture. The heat-killed LB bacteria exhibited a high adhesive property. A diffuse pattern of adhesion was observed to the undifferentiated cells, the apical brush border of the enterocytic cells, and to the mucus layer that covered the surface of the mucus-secreting cells. The inhibitory effect of heat-killed LB organisms against the human intestinal Caco-2 cell-adhesion and cell-invasion by a large variety of diarrhoeagenic bacteria was investigated. The following dose-dependent inhibitions were obtained: (i) against the cell-association of enterotoxigenic, diffusely-adhering and enteropathogenic Escherichia coli, Listeria monocytogenes, Yersinia pseudotuberculosis, and Salmonella typhimurium; (ii) against the cell-invasion by enteropathogenic Escherichia coli, Yersinia pseudotuberculosis, Listeria monocytogenes and Salmonella typhimurium. PMID:8188996

  9. Dual Pili Post-translational Modifications Synergize to Mediate Meningococcal Adherence to Platelet Activating Factor Receptor on Human Airway Cells

    PubMed Central

    Schulz, Benjamin L.; Power, Peter M.; Swords, W. Edward; Weiser, Jeffery N.; Apicella, Michael A.; Edwards, Jennifer L.; Jennings, Michael P.

    2013-01-01

    Pili of pathogenic Neisseria are major virulence factors associated with adhesion, twitching motility, auto-aggregation, and DNA transformation. Pili of N. meningitidis are subject to several different post-translational modifications. Among these pilin modifications, the presence of phosphorylcholine (ChoP) and a glycan on the pilin protein are phase-variable (subject to high frequency, reversible on/off switching of expression). In this study we report the location of two ChoP modifications on the C-terminus of N. meningitidis pilin. We show that the surface accessibility of ChoP on pili is affected by phase variable changes to the structure of the pilin-linked glycan. We identify for the first time that the platelet activating factor receptor (PAFr) is a key, early event receptor for meningococcal adherence to human bronchial epithelial cells and tissue, and that synergy between the pilin-linked glycan and ChoP post-translational modifications is required for pili to optimally engage PAFr to mediate adherence to human airway cells. PMID:23696740

  10. Receptor-like glycocompounds in human milk that inhibit classical and El Tor Vibrio cholerae cell adherence (hemagglutination).

    PubMed Central

    Holmgren, J; Svennerholm, A M; Lindblad, M

    1983-01-01

    The two biotypes of Vibrio cholerae were found to have cell-associated hemagglutinins which differ with regard to binding to different species of erythrocytes and inhibition by monosaccharides. A total of 12 classical V. cholerae strains (Inaba or Ogawa) strongly agglutinated human erythrocytes in a reaction specifically inhibited by L-fucose, whereas 12 El Tor strains preferably agglutinated chicken erythrocytes, a reaction reversed by D-mannose or by higher concentrations of D-fructose, D-glucose, alpha-methyl-D-mannoside, or sucrose. Milk from Swedish women inhibited both of these adherence reactions, and the predominating inhibitory activity for each reaction resisted boiling, was destroyed by periodate treatment, and bound a concanavalin A-Sepharose column, suggesting a carbohydrate structure. Further characterization indicated that the inhibitory activity for classical V. cholerae hemagglutination was distributed about equally on glycoprotein and free oligosaccharide, but was not present on glycolipid. The El Tor inhibiting activity, on the other hand, was almost exclusively of a high-molecular-weight glycoprotein nature. These results support our previous suggestion (Holmgren et al., Infect. Immun. 33:136-141, 1981) that human milk may contain receptor-like glycocompounds which can prevent bacterial adherence by competition with receptors on target cells. PMID:6295953

  11. Inhibition of Streptococcus pneumoniae adherence to human epithelial cells in vitro by the probiotic Lactobacillus rhamnosus GG

    PubMed Central

    2013-01-01

    Background Colonization of the nasopharynx by Streptococcus pneumoniae is considered a prerequisite for pneumococcal infections such as pneumonia and otitis media. Probiotic bacteria can influence disease outcomes through various mechanisms, including inhibition of pathogen colonization. Here, we examine the effect of the probiotic Lactobacillus rhamnosus GG (LGG) on S. pneumoniae colonization of human epithelial cells using an in vitro model. We investigated the effects of LGG administered before, at the same time as, or after the addition of S. pneumoniae on the adherence of four pneumococcal isolates. Results LGG significantly inhibited the adherence of all the pneumococcal isolates tested. The magnitude of inhibition varied with LGG dose, time of administration, and the pneumococcal isolate used. Inhibition was most effective when a higher dose of LGG was administered prior to establishment of pneumococcal colonization. Mechanistic studies showed that LGG binds to epithelial cells but does not affect pneumococcal growth or viability. Administration of LGG did not lead to any significant changes in host cytokine responses. Conclusions These findings demonstrate that LGG can inhibit pneumococcal colonization of human epithelial cells in vitro and suggest that probiotics could be used clinically to prevent the establishment of pneumococcal carriage. PMID:23561014

  12. Adherence performances of pressure sensitive adhesives on a model viscoelastic synthetic film: a tool for the understanding of adhesion on the human skin.

    PubMed

    Renvoise, Julien; Burlot, Delphine; Marin, Gérard; Derail, Christophe

    2009-02-23

    This work deals with the rheological behavior and adherence properties of pressure sensitive adhesive formulations dedicated to medical applications. We have developed a specific viscoelastic substrate which mimics adhesion on human skin to measure the adherence properties of PSAs when they are stuck on the human skin. By comparing peeling results of PSAs, dedicated to medical applications, stuck on human skin and on this viscoelastic substrate we show that this substrate, based on a blend of natural proteins, presents a better representation of the interactions occurring at the skin/adhesive interface than conventional substrates used for peel test (i.e. glass and steel). PMID:18992309

  13. Rethinking adherence.

    PubMed

    Steiner, John F

    2012-10-16

    In 2012, the Centers for Medicare & Medicaid Services (CMS) will introduce measures of adherence to oral hypoglycemic, antihypertensive, and cholesterol-lowering drugs into its Medicare Advantage quality program. To meet these quality goals, delivery systems will need to develop and disseminate strategies to improve adherence. The design of adherence interventions has too often been guided by the mistaken assumptions that adherence is a single behavior that can be predicted from readily available patient characteristics and that individual clinicians alone can improve adherence at the population level.Effective interventions require recognition that adherence is a set of interacting behaviors influenced by individual, social, and environmental forces; adherence interventions must be broadly based, rather than targeted to specific population subgroups; and counseling with a trusted clinician needs to be complemented by outreach interventions and removal of structural and organizational barriers. To achieve the adherence goals set by CMS, front-line clinicians, interdisciplinary teams, organizational leaders, and policymakers will need to coordinate efforts in ways that exemplify the underlying principles of health care reform. PMID:23070491

  14. Characterization of Three-Dimensional Retinal Tissue Derived from Human Embryonic Stem Cells in Adherent Monolayer Cultures.

    PubMed

    Singh, Ratnesh K; Mallela, Ramya K; Cornuet, Pamela K; Reifler, Aaron N; Chervenak, Andrew P; West, Michael D; Wong, Kwoon Y; Nasonkin, Igor O

    2015-12-01

    Stem cell-based therapy of retinal degenerative conditions is a promising modality to treat blindness, but requires new strategies to improve the number of functionally integrating cells. Grafting semidifferentiated retinal tissue rather than progenitors allows preservation of tissue structure and connectivity in retinal grafts, mandatory for vision restoration. Using human embryonic stem cells (hESCs), we derived retinal tissue growing in adherent conditions consisting of conjoined neural retina and retinal pigment epithelial (RPE) cells and evaluated cell fate determination and maturation in this tissue. We found that deriving such tissue in adherent conditions robustly induces all eye field genes (RX, PAX6, LHX2, SIX3, SIX6) and produces four layers of pure populations of retinal cells: RPE (expressing NHERF1, EZRIN, RPE65, DCT, TYR, TYRP, MITF, PMEL), early photoreceptors (PRs) (coexpressing CRX and RCVRN), inner nuclear layer neurons (expressing CALB2), and retinal ganglion cells [RGCs, expressing BRN3B and Neurofilament (NF) 200]. Furthermore, we found that retinal progenitors divide at the apical side of the hESC-derived retinal tissue (next to the RPE layer) and then migrate toward the basal side, similar to that found during embryonic retinogenesis. We detected synaptogenesis in hESC-derived retinal tissue, and found neurons containing many synaptophysin-positive boutons within the RGC and PR layers. We also observed long NF200-positive axons projected by RGCs toward the apical side. Whole-cell recordings demonstrated that putative amacrine and/or ganglion cells exhibited electrophysiological responses reminiscent of those in normal retinal neurons. These responses included voltage-gated Na(+) and K(+) currents, depolarization-induced spiking, and responses to neurotransmitter receptor agonists. Differentiation in adherent conditions allows generation of long and flexible pieces of 3D retinal tissue suitable for isolating transplantable slices of tissue

  15. Nuclear p120 catenin unlocks mitotic block of contact-inhibited human corneal endothelial monolayers without disrupting adherent junctions.

    PubMed

    Zhu, Ying-Ting; Chen, Hung-Chi; Chen, Szu-Yu; Tseng, Scheffer C G

    2012-08-01

    Contact inhibition ubiquitously exists in non-transformed cells that are in contact with neighboring cells. This phenomenon explains the poor regenerative capacity of in vivo human corneal endothelial cells during aging, injury and surgery. This study demonstrated that the conventional approach of expanding human corneal endothelial cells by disrupting contact inhibition with EDTA followed by bFGF activated canonical Wnt signaling and lost the normal phenotype to endothelial-mesenchymal transition, especially if TGFβ1 was added. By contrast, siRNA against p120 catenin (CTNND1) also uniquely promoted proliferation of the endothelial cells by activating trafficking of p120 catenin to the nucleus, thus relieving repression by nuclear Kaiso. This nuclear p120-catenin-Kaiso signaling is associated with activation of RhoA-ROCK signaling, destabilization of microtubules and inhibition of Hippo signaling, but not with activation of Wnt-β-catenin signaling. Consequently, proliferating human corneal endothelial cells maintained a hexagonal shape, with junctional expression of N-cadherin, ZO-1 and Na(+)/K(+)-ATPase. Further expansion of human corneal endothelial monolayers with a normal phenotype and a higher density was possible by prolonging treatment with p120 catenin siRNA followed by its withdrawal. This new strategy of perturbing contact inhibition by selective activation of p120-catenin-Kaiso signaling without disrupting adherent junction could be used to engineer surgical grafts containing normal human corneal endothelial cells to meet a global corneal shortage and for endothelial keratoplasties. PMID:22505615

  16. beta-Dystroglycan modulates the interplay between actin and microtubules in human-adhered platelets.

    PubMed

    Cerecedo, Doris; Cisneros, Bulmaro; Suárez-Sánchez, Rocío; Hernández-González, Enrique; Galván, Iván

    2008-05-01

    To maintain the continuity of an injured blood vessel, platelets change shape, secrete granule contents, adhere, aggregate, and retract in a haemostatic plug. Ordered arrays of microtubules, microfilaments, and associated proteins are responsible for these platelet responses. In full-spread platelets, microfilament bundles in association with other cytoskeleton proteins are anchored in focal contacts. Recent studies in migrating cells suggest that co-ordination and direct physical interaction of microtubules and actin network modulate adhesion development. In platelets, we have proposed a feasible association between these two cytoskeletal systems, as well as the participation of the dystrophin-associated protein complex, as part of the focal adhesion complex. The present study analysed the participation of microtubules and actin during the platelet adhesion process. Confocal microscopy, fluorescence resonance transfer energy and immunoprecipitation assays were used to provide evidence of a cross-talk between these two cytoskeletal systems. Interestingly, beta-dystroglycan was found to act as an interplay protein between actin and microtubules and an additional communication between these two cytoskeleton networks was maintained through proteins of focal adhesion complex. Altogether our data are indicative of a dynamic co-participation of actin filaments and microtubules in modulating focal contacts to achieve platelet function. PMID:18341635

  17. Increased Rate of Apoptosis and Diminished Phagocytic Ability of Human Neutrophils Infected with Afa/Dr Diffusely Adhering Escherichia coli Strains

    PubMed Central

    Brest, Patrick; Bétis, Frédéric; Çuburu, Nicolas; Selva, Eric; Herrant, Magali; Servin, Alain; Auberger, Patrick; Hofman, Paul

    2004-01-01

    The proinflammatory effect of Afa/Dr diffusely adhering Escherichia coli (Afa/Dr DAEC) strains have been recently demonstrated in vitro by showing that polymorphonuclear leukocyte (PMN) transepithelial migration is induced after bacterial colonization of apical intestinal monolayers. The effect of Afa/Dr DAEC-PMN interaction on PMN behavior has been not investigated. Because of the putative virulence mechanism of PMN apoptosis during infectious diseases and taking into account the high level of expression of the decay-accelerating factor (DAF, or CD55), the receptor of Afa/Dr DAEC on PMNs, we sought to determine whether infection of PMNs by Afa/Dr DAEC strains could promote cell apoptosis. We looked at the behavior of PMNs incubated with Afa/Dr DAEC strains once they had transmigrated across polarized monolayers of intestinal (T84) cells. Infection of PMNs by Afa/Dr DAEC strains induced PMN apoptosis characterized by morphological nuclear changes, DNA fragmentation, caspase activation, and a high level of annexin V expression. However, transmigrated and nontransmigrated PMNs incubated with Afa/Dr DAEC strains showed similar elevated global caspase activities. PMN apoptosis depended on their agglutination, induced by Afa/Dr DAEC, and was still observed after preincubation of PMNs with anti-CD55 and/or anti-CD66 antibodies. Low levels of phagocytosis of Afa/Dr DAEC strains were observed both in nontransmigrated and in transmigrated PMNs compared to that observed with the control E. coli DH5α strain. Taken together, these data strongly suggest that interaction of Afa/Dr DAEC with PMNs may increase the bacterial virulence both by inducing PMN apoptosis through an agglutination process and by diminishing their phagocytic capacity. PMID:15385473

  18. Interactions between Periodontal Bacteria and Human Oral Epithelial Cells: Fusobacterium nucleatum Adheres to and Invades Epithelial Cells

    PubMed Central

    Han, Yiping W.; Shi, Wenyuan; Huang, George T.-J.; Kinder Haake, Susan; Park, No-Hee; Kuramitsu, Howard; Genco, Robert J.

    2000-01-01

    Bacteria are causative agents of periodontal diseases. Interactions between oral bacteria and gingival epithelial cells are essential aspects of periodontal infections. Using an in vitro tissue culture model, a selected group of gram-negative anaerobic bacteria frequently associated with periodontal diseases, including Bacteroides forsythus, Campylobacter curvus, Eikenella corrodens, Fusobacterium nucleatum, Porphyromonas gingivalis, and Prevotella intermedia, were examined for their ability to adhere to and invade primary cultures of human gingival epithelial cells (HGEC). The effects of these bacteria on the production of interleukin-8 (IL-8), a proinflammatory chemokine, were also measured. These studies provided an initial demonstration that F. nucleatum adhered to and invaded HGEC and that this was accompanied by high levels of IL-8 secretion from the epithelial cells. The attachment and invasion characteristics of F. nucleatum were also tested using KB cells, an oral epithelial cell line. The invasion was verified by transmission electron microscopy and with metabolic inhibitors. Invasion appeared to occur via a “zipping” mechanism and required the involvement of actins, microtubules, signal transduction, protein synthesis, and energy metabolism of the epithelial cell, as well as protein synthesis by F. nucleatum. A spontaneous mutant, lam, of F. nucleatum, isolated as defective in autoagglutination, was unable to attach to or invade HGEC or KB cells, further indicating the requirement of bacterial components in these processes. Sugar inhibition assays indicated that lectin-like interactions were involved in the attachment of F. nucleatum to KB cells. Investigation of these new virulence phenotypes should improve our understanding of the role of F. nucleatum in periodontal infections. PMID:10816455

  19. IL-4 induces adherence of human eosinophils and basophils but not neutrophils to endothelium. Association with expression of VCAM-1.

    PubMed

    Schleimer, R P; Sterbinsky, S A; Kaiser, J; Bickel, C A; Klunk, D A; Tomioka, K; Newman, W; Luscinskas, F W; Gimbrone, M A; McIntyre, B W

    1992-02-15

    The present studies were performed to explore potentially selective mechanisms of leukocyte adhesion in an attempt to understand how preferential recruitment of eosinophils and basophils might occur during allergic and other inflammatory reactions. Stimulation of human vascular endothelial cells for 24 h with IL-4 (30 to 1,000 U/ml) induced adhesion for eosinophils (up to approximately four-fold of control) and basophils (up to approximately twofold of control) but not neutrophils (less than 125% of control). Analysis of endothelial expression of adhesion molecules by flow cytometry revealed that IL-4 treatment induced vascular cell adhesion molecule-1 (VCAM-1) expression without significantly affecting the expression of other adhesion molecules, namely endothelial-leukocyte adhesion molecule-1 (ELAM-1) or intercellular adhesion molecule-1 (ICAM-1). The concentration-response curve for IL-4-induced VCAM-1 expression paralleled that for adhesion. Endothelial cells stimulated with IL-4 expressed adhesive properties for eosinophils by 3 h; the response increased steadily during a 24-h time course study. Eosinophils and basophils adhered to plates coated with a recombinant form of VCAM-1. This adhesion was blocked with antibodies to VCAM-1 but not ELAM-1. mAb directed against either VCAM-1 or VLA-4 inhibited (by approximately 75%) the binding of eosinophils and basophils to IL-4-stimulated endothelial cells. Because VLA-4 and VCAM-1 have been demonstrated to bind to each other in other adhesion systems, these results suggest that IL-4 stimulates eosinophil and basophil adhesion by inducing endothelial cell expression of VCAM-1 which binds to eosinophil and basophil VLA-4. The lack of expression of VLA-4 on neutrophils and the failure of IL-4 to stimulate neutrophil adherence support this conclusion. It is proposed that local release of IL-4 in vivo in allergic diseases or after experimental allergen challenge may partly explain the enrichment of eosinophils and

  20. The small regulatory RNA FasX controls pilus expression and adherence in the human bacterial pathogen group A Streptococcus

    PubMed Central

    Liu, Zhuyun; Treviño, Jeanette; Ramirez-Peña, Esmeralda; Sumby, Paul

    2012-01-01

    Summary Bacterial pathogens use cell-surface-associated adhesion molecules to promote host attachment and colonization, and the ability to modulate adhesion expression is critical to pathogen success. Here, we show that the human-specific pathogen the group A Streptococcus (GAS) uses a small regulatory RNA (sRNA) to regulate the expression of adhesive pili. The fibronectin / fibrinogen-binding / haemolytic-activity / streptokinase-regulator-X (FasX) sRNA, previously shown to positively regulate expression of the secreted virulence factor streptokinase (SKA), negatively regulates the production of pili on the GAS cell surface. FasX base-pairs to the extreme 5’ end of mRNA from the pilus biosynthesis operon, and this RNA:RNA interaction reduces the stability of the mRNA, while also inhibiting translation of at least the first gene in the pilus biosynthesis operon (cpa, which encodes a minor pilin protein). The negative regulation of pilus expression by FasX reduces the ability of GAS to adhere to human keratinocytes. Our findings cement FasX sRNA as an important regulator of virulence factor production in GAS and identify that FasX uses at least three distinct mechanisms, positive (ska mRNA) and negative (pilus operon mRNA) regulation of mRNA stability, and negative regulation of mRNA translation (cpa mRNA), to post-transcriptionally regulate target mRNAs during infection. PMID:22882718

  1. Humans robustly adhere to dynamic walking principles by harnessing motor abundance to control forces

    PubMed Central

    Toney, Megan E.

    2013-01-01

    Human walking dynamics are typically framed in the context of mechanics and energetics rather than in the context of neuromuscular control. Dynamic walking principles describe one helpful theoretical approach to characterize efficient human walking mechanics over many steps. These principles do not, however, address how such walking is controlled step-by-step despite small perturbations from natural variability. Our purpose was to identify neuromechanical control strategies used to achieve consistent and robust locomotion despite natural step-to-step force variability. We used the uncontrolled manifold concept to test whether human walkers select combinations of leading and trailing leg-forces that generate equivalent net-force trajectories during step-to-step transitions. Subjects selected leading and trailing leg-force combinations that generated consistent vertical net-force during step-to-step transitions. We conclude that vertical net-force is an implicit neuromechanical goal of human walking whose trajectory is stabilized for consistent step-to-step transitions, which agrees with the principles of dynamic walking. In contrast, inter-leg-force combinations modulated anterior–posterior net-force trajectories with each step to maintain constant walking speed, indicating that a consistent anterior–posterior net-force trajectory is not an implicit goal of walking. For a more complete picture of hierarchical locomotor control, we also tested whether each individual leg-force trajectory was stabilized through the selection of leg-force equivalent joint-torque combinations. The observed consistent vertical net-force trajectory was achieved primarily through the selection of joint-torque combinations that modulated trailing leg-force during step-to-step transitions. We conclude that humans achieve robust walking by harnessing inherent motor abundance of the joints and legs to maintain consistent step-by-step walking performance. PMID:24081680

  2. Human Placenta-Derived Adherent Cells Prevent Bone loss, Stimulate Bone formation, and Suppress Growth of Multiple Myeloma in Bone

    PubMed Central

    Li, Xin; Ling, Wen; Pennisi, Angela; Wang, Yuping; Khan, Sharmin; Heidaran, Mohammad; Pal, Ajai; Zhang, Xiaokui; He, Shuyang; Zeitlin, Andy; Abbot, Stewart; Faleck, Herbert; Hariri, Robert; Shaughnessy, John D.; van Rhee, Frits; Nair, Bijay; Barlogie, Bart; Epstein, Joshua; Yaccoby, Shmuel

    2011-01-01

    Human placenta has emerged as a valuable source of transplantable cells of mesenchymal and hematopoietic origin for multiple cytotherapeutic purposes, including enhanced engraftment of hematopoietic stem cells, modulation of inflammation, bone repair, and cancer. Placenta-derived adherent cells (PDACs) are mesenchymal-like stem cells isolated from postpartum human placenta. Multiple myeloma is closely associated with induction of bone disease and large lytic lesions, which are often not repaired and are usually the sites of relapses. We evaluated the antimyeloma therapeutic potential, in vivo survival, and trafficking of PDACs in the severe combined immunodeficiency (SCID)–rab model of medullary myeloma-associated bone loss. Intrabone injection of PDACs into non-myelomatous and myelomatous implanted bone in SCID-rab mice promoted bone formation by stimulating endogenous osteoblastogenesis, and most PDACs disappeared from bone within 4 weeks. PDACs inhibitory effects on myeloma bone disease and tumor growth were dose-dependent and comparable with those of fetal human mesenchymal stem cells (MSCs). Intrabone, but not subcutaneous, engraftment of PDACs inhibited bone disease and tumor growth in SCID-rab mice. Intratumor injection of PDACs had no effect on subcutaneous growth of myeloma cells. A small number of intravenously injected PDACs trafficked into myelomatous bone. Myeloma cell growth rate in vitro was lower in coculture with PDACs than with MSCs from human fetal bone or myeloma patients. PDACs also promoted apoptosis in osteoclast precursors and inhibited their differentiation. This study suggests that altering the bone marrow microenvironment with PDAC cytotherapy attenuates growth of myeloma and that PDAC cytotherapy is a promising therapeutic approach for myeloma osteolysis. PMID:21732484

  3. A Serine-Threonine Kinase (StkP) Regulates Expression of the Pneumococcal Pilus and Modulates Bacterial Adherence to Human Epithelial and Endothelial Cells In Vitro

    PubMed Central

    Herbert, Jenny A.; Mitchell, Andrea M.; Mitchell, Timothy J.

    2015-01-01

    The pneumococcal serine threonine protein kinase (StkP) acts as a global regulator in the pneumococcus. Bacterial mutants deficient in StkP are less virulent in animal models of infection. The gene for this regulator is located adjacent to the gene for its cognate phosphatase in the pneumococcal genome. The phosphatase dephosphorylates proteins phosphorylated by StkP and has been shown to regulate a number of key pneumococcal virulence factors and to modulate adherence to eukaryotic cells. The role of StkP in adherence of pneumococci to human cells has not previously been reported. In this study we show StkP represses the pneumococcal pilus, a virulence factor known to be important for bacterial adhesion. In a serotype 4 strain regulation of the pilus by StkP modulates adherence to human brain microvascular endothelial cells (HBMEC) and human lung epithelial cells. This suggests that the pneumococcal pilus may play a role in adherence during infections such as meningitis and pneumonia. We show that regulation of the pilus occurs at the population level as StkP alters the number of pili-positive cells within a single culture. As far as we are aware this is the first gene identified outside of the pilus islet that regulates the biphasic expression of the pilus. These findings suggest StkPs role in cell division may be linked to regulation of expression of a cell surface adhesin. PMID:26090876

  4. The effects of plasma-processing conditions on the morphology of adherent human blood platelets

    SciTech Connect

    Murugesan, R.; Hanley, E.; Lauer, J. L.; Shohet, J. L.; Albrecht, R. M.; Heintz, J. A.; Oliver, J. A.

    2008-05-01

    Hematocompatibility and nonfouling properties of materials are crucial for the development of small-scale biomedical devices. This study examines the adhesion and morphology of purified human platelets on plasma-polymerized tetraglyme-coated glass substrates. The effect of varying the plasma-processing parameters on platelet responses was determined using scanning electron microscopy. Images of platelets on the coated surfaces show that a significant reduction in platelet adhesion and spreading can be achieved as the processing parameters are varied.

  5. cGMP-Compliant Expansion of Human iPSC Cultures as Adherent Monolayers.

    PubMed

    Parr, Ann M; Walsh, Patrick J; Truong, Vincent; Dutton, James R

    2016-01-01

    Therapeutic uses of cells differentiated from human pluripotent stem cells (hPSCs), either embryonic stem (ES) cells or induced pluripotent stem cells (iPSCs), are now being tested in clinical trials, and it is likely that this will lead to increased commercial interest in the clinical translation of promising hPSC research. Recent technical advances in the use of defined media and culture substrates have significantly improved both the simplicity and predictability of growing hPSCs, allowing a much more straightforward application of current good manufacturing practices (cGMP) to the culture of these cells. In addition, the adoption of cGMP-compliant techniques in research environments will both improve the replication of results and make the transition of promising investigations to the commercial sector significantly less cumbersome. However, passaging methods for hPSCs are inherently unpredictable and rely on operator experience and expertise. This is problematic for the cell manufacturing process where operator time and process predictability are often determining cost drivers. We have adopted a human iPSC system using defined media and a recombinant substrate that employs cell dissociation with a hypertonic citrate solution which eliminates variability during hPSC cell expansion and provides a simple cGMP-compliant technique for hiPSC cultivation that is appropriate in both research and commercial applications. PMID:25863788

  6. Specific adherence of Borrelia burgdorferi extracellular vesicles to human endothelial cells in culture.

    PubMed Central

    Shoberg, R J; Thomas, D D

    1993-01-01

    Borrelia burgdorferi produces extracellular vesicles which contain some of the outer surface proteins of the bacterium (e.g., OspA and OspB). Borrelial vesicles, isolated by differential centrifugation and filtration, were tested for the ability to bind to cultured human umbilical vein endothelial (HUVE) cells in culture. The recently described lipoprotein OspD was expressed on vesicles. Vesicles exhibited differential expression of OspB and OspD in a relationship with passage number and medium serum supplement type, respectively. Qualitative immunoblotting analyses demonstrated dose-dependent, passage number-dependent adsorption of vesicles by HUVE cells. This adsorption was demonstrated to be dependent upon a borrelial component of the vesicle and not due to the presence of minor contamination with intact spirochetes. Quantitative experiments examining inhibition of B. burgdorferi-HUVE association as a function of prior vesicle-HUVE association demonstrated dependence upon (i) a borrelial component(s) in the vesicle, (ii) low passage number, and (iii) vesicle protein concentration. However, vesicle pretreatment of the HUVE cell monolayer was not requisite for this inhibition. Vesicles from highly passaged borrelias were noninhibitory for B. burgdorferi-HUVE cell association, regardless of the serum used to supplement the medium. The use of vesicles as a tool for studying B. burgdorferi pathogenesis and/or physiology is proposed. Images PMID:8359911

  7. αVβ3 Integrin Regulation of Respiratory Burst in Fibrinogen Adherent Human Neutrophils

    PubMed Central

    Kim, Hye-Yeong; Skokos, Eleni A.; Myer, Deborah J.; Agaba, Perez; Gonzalez, Anjelica L.

    2015-01-01

    In response to inflammatory stimuli, microvascular endothelial cells become activated, initiating the capture and exit of neutrophils from the blood vessel and into the extravascular extracellular matrix (ECM). In the extravascular space, neutrophils bind to ECM proteins, regulating cellular functions via signaling through adhesion molecules known as integrins. The αVβ3 integrin is an important mediator of neutrophil adhesion to ECM proteins containing the Arg-Gly-Asp (RGD) peptide sequence, including fibrinogen and fibronectin. Despite the abundance of RGD sequence in the ECM, adhesion molecule-mediated neutrophil activity has been focused on the β2 (Mac-1, CD11b/CD18) and β1 integrin response to matrix proteins. Here we investigated αVβ3 integrin-mediated reactive oxidant suppression as a consequence of human neutrophil adhesion to RGD containing proteins. Using integrin ligand-modified (poly)ethylene glycol hydrogels and reactive oxygen species (ROS) sensitive fluorescent probes (dihydrotetramethylrhosamine, H2TMRos), we evaluated integrin–peptide interactions that effectively regulate ROS generation. This study demonstrates that neutrophil adhesion suppresses ROS production in an αVβ3-dependent manner. Additionally, we determine that p38 mitogen-activated protein kinase in the respiratory burst signaling pathway is interrupted by integrin-mediated adhesion. These data indicate that ECM/integrin interactions can induce αVβ3-mediated adhesion dependent downstream signaling of ROS regulation via a Mac-1 independent mechanism. PMID:25632307

  8. Experimental evidence for the role of lipids in adherence of Candida spp. to human buccal epithelial cells.

    PubMed Central

    Ghannoum, M A; Burns, G R; Elteen, K A; Radwan, S S

    1986-01-01

    Lipids extracted from Candida albicans and C. tropicalis, but not from the weakly adherent C. pseudotropicalis, significantly blocked in vitro adherence of the respective yeast cells to buccal epithelial cells. The percentage of reduction from control values ranged between 16.4 and 42.1%, depending on the species, the strain, and the solvent used for lipid extraction. The constituent lipid classes of both the acetone and chloroform-methanol extracts of C. albicans ATCC 10231 were qualitatively and quantitatively analyzed. The individual classes were isolated by preparative thin-layer chromatography and then tested for their effects on the adherence of this strain to buccal epithelial cells. Individual phospholipids, sterols, and steryl esters blocked adherence significantly (between 15.5 and 55.7% reduction). Triacylglycerols and free fatty acids showed no effect whatsoever. The same results were obtained when standard lipid samples were investigated. Images PMID:3759234

  9. Cryptococcal Antigenemia in Nigerian Patients With Advanced Human Immunodeficiency Virus: Influence of Antiretroviral Therapy Adherence

    PubMed Central

    Oladele, Rita O.; Akanmu, Alani S.; Nwosu, Augustina O.; Ogunsola, Folasade T.; Richardson, Malcolm D.; Denning, David W.

    2016-01-01

    Background. Cryptococcal meningitis has a high mortality in human immunodeficiency virus (HIV)-infected persons in Africa. This is preventable with early screening and preemptive therapy. We evaluated the prevalence of cryptococcal disease by antigen testing, possible associated factors, and outcomes in HIV-infected patients being managed in a tertiary hospital in Lagos, Nigeria. Methods. Sera were collected from 214 consenting HIV-infected participants with CD4+ counts <250 cells/mm3, irrespective of their antiretroviral therapy (ART) status, between November 2014 and May 2015. A cryptococcal antigen (CrAg) lateral flow assay was used for testing. Pertinent clinical data were obtained from patients and their case notes. Results. Of the 214 participants, females (124; 57.9%) outnumbered males. Mean age was 41.3 ± 9.4 (standard deviation) years. The majority (204; 95.3%) were ART experienced. The median CD4+ cell count was 160 cells/mm3 (interquartile range, 90–210). The overall seroprevalence of cryptococcal antigenemia was 8.9% (19 of 214); 6 of 61 (9.8%) in those with CD4+ cell counts <100 cells/mm3, 4 of 80 (5.0%) in the 100–200 group, and 9 of 73 (12.3%) in 200–250 cells/mm3 group. Among ART-naive patients, 1 of 10 (10%) was CrAg positive. Twenty-seven of 214 (12.6%) had associated oral thrush. Potential baseline meningitis symptoms (3 of 214 [1.4%] experienced neck pain or stiffness and 21 of 214 [9.8%] experienced headache) were common in the study group, but the result was not statistically significant in relation to CrAg positivity. Two of 19 (10.5%) CrAg-positive patients died, 10 of 19 (52.6%) were lost to follow up, and 7 of 19 (36.8%) were alive. Empirical fluconazole was routinely given to those with low CD4 counts <100 cells/mm3, which was unrelated to CrAg positivity (P = .018). Conclusions. We report a prevalence of 8.9% cryptococcal antigenemia in a setting where first-line antifungals are not readily available. We recommend Cr

  10. Cryptococcal Antigenemia in Nigerian Patients With Advanced Human Immunodeficiency Virus: Influence of Antiretroviral Therapy Adherence.

    PubMed

    Oladele, Rita O; Akanmu, Alani S; Nwosu, Augustina O; Ogunsola, Folasade T; Richardson, Malcolm D; Denning, David W

    2016-03-01

    Background.  Cryptococcal meningitis has a high mortality in human immunodeficiency virus (HIV)-infected persons in Africa. This is preventable with early screening and preemptive therapy. We evaluated the prevalence of cryptococcal disease by antigen testing, possible associated factors, and outcomes in HIV-infected patients being managed in a tertiary hospital in Lagos, Nigeria. Methods.  Sera were collected from 214 consenting HIV-infected participants with CD4(+) counts <250 cells/mm(3), irrespective of their antiretroviral therapy (ART) status, between November 2014 and May 2015. A cryptococcal antigen (CrAg) lateral flow assay was used for testing. Pertinent clinical data were obtained from patients and their case notes. Results.  Of the 214 participants, females (124; 57.9%) outnumbered males. Mean age was 41.3 ± 9.4 (standard deviation) years. The majority (204; 95.3%) were ART experienced. The median CD4(+) cell count was 160 cells/mm(3) (interquartile range, 90-210). The overall seroprevalence of cryptococcal antigenemia was 8.9% (19 of 214); 6 of 61 (9.8%) in those with CD4(+) cell counts <100 cells/mm(3), 4 of 80 (5.0%) in the 100-200 group, and 9 of 73 (12.3%) in 200-250 cells/mm(3) group. Among ART-naive patients, 1 of 10 (10%) was CrAg positive. Twenty-seven of 214 (12.6%) had associated oral thrush. Potential baseline meningitis symptoms (3 of 214 [1.4%] experienced neck pain or stiffness and 21 of 214 [9.8%] experienced headache) were common in the study group, but the result was not statistically significant in relation to CrAg positivity. Two of 19 (10.5%) CrAg-positive patients died, 10 of 19 (52.6%) were lost to follow up, and 7 of 19 (36.8%) were alive. Empirical fluconazole was routinely given to those with low CD4 counts <100 cells/mm(3), which was unrelated to CrAg positivity (P = .018). Conclusions.  We report a prevalence of 8.9% cryptococcal antigenemia in a setting where first-line antifungals are not readily available. We

  11. HIV Medication Adherence

    MedlinePlus

    HIV Treatment HIV Medication Adherence (Last updated 3/1/2016; last reviewed 3/1/2016) Key Points Medication adherence means sticking ... exactly as prescribed. Why is adherence to an HIV regimen important? Adherence to an HIV regimen gives ...

  12. Psychological factors, beliefs about medication, and adherence of youth with human immunodeficiency virus in a multisite directly observed therapy pilot study.

    PubMed

    Garvie, Patricia A; Flynn, Patricia M; Belzer, Marvin; Britto, Paula; Hu, Chengcheng; Graham, Bobbie; Neely, Michael; McSherry, George D; Spector, Stephen A; Gaur, Aditya H

    2011-06-01

    This study examined psychological functioning and beliefs about medicine in adolescents with human immunodeficiency virus (HIV) on highly active antiretroviral therapy in a community-based directly observed therapy (DOT) pilot feasibility study. Participants were youth with behaviorally acquired HIV (n = 20; 65% female; median age, 21 years) with adherence problems, who received once-daily DOT. Youth were assessed at baseline, week 12 (post-DOT), and week 24 (follow-up). At baseline, 55% of youth reported having clinical depressive symptoms compared to 27% at week 12 with sustained improvements at week 24. At baseline, substance use was reported within the borderline clinical range (T(score) = 68), with clinical but statistically nonsignificant improvement (T(score) = 61) at week 12. Hopelessness scores reflected optimism for the future. Coping strategies showed significantly decreased cognitive avoidance (p = .02), emotional discharge (p = .004), and acceptance/resignation ("nothing I can do," p = .004), whereas positive reappraisal and seeking support emerged. With the exception of depressive symptoms, week 12 improvements were not sustained at week 24. DOT adherence was predicted by higher baseline depression (p = .05), beliefs about medicine (p = .006) and perceived threat of illness scores (p = .03). Youth with behaviorally acquired HIV and adherence problems who participated in a community-based DOT intervention reported clinically improved depressive symptoms, and temporarily reduced substance use and negative coping strategies. Depressive symptoms, beliefs about medicine, and viewing HIV as a potential threat predicted better DOT adherence. PMID:21575827

  13. The pathogenic potential of Helicobacter cinaedi isolated from non-human sources: adherence, invasion and translocation ability in polarized intestinal epithelial Caco-2 cells in vitro

    PubMed Central

    TANIGUCHI, Takako; YAMAZAKI, Wataru; SAEKI, Yuji; TAKAJO, Ichiro; OKAYAMA, Akihiko; HAYASHI, Tetsuya; MISAWA, Naoaki

    2015-01-01

    Helicobacter cinaedi infection has been recognized as an increasingly important emerging disease in humans. Infection with H. cinaedi causes bacteremia, cellulitis and enteritis. H. cinaedi has been isolated from non-human sources, including dogs, cats and rodents; however, it remains unclear whether animal strains are pathogenic in humans and as zoonotic pathogens. In this study, H. cinaedi isolates were recovered from a dog and a hamster, and the ability of these isolates to adhere to, invade and translocate across polarized human intestinal epithelial Caco-2 cells was examined in vitro. To better understand the pathogenic potential of animal H. cinaedi isolates, these results were compared with those for a human strain that was isolated from a patient with bacteremia. The animal and human strains adhered to and invaded Caco-2 cells, but to a lesser degree than the C. jejuni 81–176 strain, which was used as a control. The integrity of tight junctions was monitored by measuring transepithelial electrical resistance (TER) with a membrane insert system. The TER values for all H. cinaedi strains did not change during the experimental periods compared with those of the controls; however, translocation of H. cinaedi from the apical side to the basolateral side was confirmed by cultivation and H. cinaedi-specific PCR, suggesting that the H. cinaedi strains translocated by transcellular route. This study demonstrated that H. cinaedi strains of animal origin might have a pathogenic potential in human epithelial cells as observed in a translocation assay in vitro with a human isolate. PMID:26685883

  14. The pathogenic potential of Helicobacter cinaedi isolated from non-human sources: adherence, invasion and translocation ability in polarized intestinal epithelial Caco-2 cells in vitro.

    PubMed

    Taniguchi, Takako; Yamazaki, Wataru; Saeki, Yuji; Takajo, Ichiro; Okayama, Akihiko; Hayashi, Tetsuya; Misawa, Naoaki

    2016-05-01

    Helicobacter cinaedi infection has been recognized as an increasingly important emerging disease in humans. Infection with H. cinaedi causes bacteremia, cellulitis and enteritis. H. cinaedi has been isolated from non-human sources, including dogs, cats and rodents; however, it remains unclear whether animal strains are pathogenic in humans and as zoonotic pathogens. In this study, H. cinaedi isolates were recovered from a dog and a hamster, and the ability of these isolates to adhere to, invade and translocate across polarized human intestinal epithelial Caco-2 cells was examined in vitro. To better understand the pathogenic potential of animal H. cinaedi isolates, these results were compared with those for a human strain that was isolated from a patient with bacteremia. The animal and human strains adhered to and invaded Caco-2 cells, but to a lesser degree than the C. jejuni 81-176 strain, which was used as a control. The integrity of tight junctions was monitored by measuring transepithelial electrical resistance (TER) with a membrane insert system. The TER values for all H. cinaedi strains did not change during the experimental periods compared with those of the controls; however, translocation of H. cinaedi from the apical side to the basolateral side was confirmed by cultivation and H. cinaedi-specific PCR, suggesting that the H. cinaedi strains translocated by transcellular route. This study demonstrated that H. cinaedi strains of animal origin might have a pathogenic potential in human epithelial cells as observed in a translocation assay in vitro with a human isolate. PMID:26685883

  15. Mitigation of Lethal Radiation Syndrome in Mice by Intramuscular Injection of 3D Cultured Adherent Human Placental Stromal Cells

    PubMed Central

    Gaberman, Elena; Pinzur, Lena; Levdansky, Lilia; Tsirlin, Maria; Netzer, Nir; Aberman, Zami; Gorodetsky, Raphael

    2013-01-01

    Exposure to high lethal dose of ionizing radiation results in acute radiation syndrome with deleterious systemic effects to different organs. A primary target is the highly sensitive bone marrow and the hematopoietic system. In the current study C3H/HeN mice were total body irradiated by 7.7 Gy. Twenty four hrs and 5 days after irradiation 2×106 cells from different preparations of human derived 3D expanded adherent placental stromal cells (PLX) were injected intramuscularly. Treatment with batches consisting of pure maternal cell preparations (PLX-Mat) increased the survival of the irradiated mice from ∼27% to 68% (P<0.001), while cell preparations with a mixture of maternal and fetal derived cells (PLX-RAD) increased the survival to ∼98% (P<0.0001). The dose modifying factor of this treatment for both 50% and 37% survival (DMF50 and DMF37) was∼1.23. Initiation of the more effective treatment with PLX-RAD injection could be delayed for up to 48 hrs after irradiation with similar effect. A delayed treatment by 72 hrs had lower, but still significantly effect (p<0.05). A faster recovery of the BM and improved reconstitution of all blood cell lineages in the PLX-RAD treated mice during the follow-up explains the increased survival of the cells treated irradiated mice. The number of CD45+/SCA1+ hematopoietic progenitor cells within the fast recovering population of nucleated BM cells in the irradiated mice was also elevated in the PLX-RAD treated mice. Our study suggests that IM treatment with PLX-RAD cells may serve as a highly effective “off the shelf” therapy to treat BM failure following total body exposure to high doses of radiation. The results suggest that similar treatments may be beneficial also for clinical conditions associated with severe BM aplasia and pancytopenia. PMID:23823334

  16. Mitigation of Lethal Radiation Syndrome in Mice by Intramuscular Injection of 3D Cultured Adherent Human Placental Stromal Cells.

    PubMed

    Gaberman, Elena; Pinzur, Lena; Levdansky, Lilia; Tsirlin, Maria; Netzer, Nir; Aberman, Zami; Gorodetsky, Raphael

    2013-01-01

    Exposure to high lethal dose of ionizing radiation results in acute radiation syndrome with deleterious systemic effects to different organs. A primary target is the highly sensitive bone marrow and the hematopoietic system. In the current study C3H/HeN mice were total body irradiated by 7.7 Gy. Twenty four hrs and 5 days after irradiation 2×10(6) cells from different preparations of human derived 3D expanded adherent placental stromal cells (PLX) were injected intramuscularly. Treatment with batches consisting of pure maternal cell preparations (PLX-Mat) increased the survival of the irradiated mice from ∼27% to 68% (P<0.001), while cell preparations with a mixture of maternal and fetal derived cells (PLX-RAD) increased the survival to ∼98% (P<0.0001). The dose modifying factor of this treatment for both 50% and 37% survival (DMF50 and DMF37) was∼1.23. Initiation of the more effective treatment with PLX-RAD injection could be delayed for up to 48 hrs after irradiation with similar effect. A delayed treatment by 72 hrs had lower, but still significantly effect (p<0.05). A faster recovery of the BM and improved reconstitution of all blood cell lineages in the PLX-RAD treated mice during the follow-up explains the increased survival of the cells treated irradiated mice. The number of CD45+/SCA1+ hematopoietic progenitor cells within the fast recovering population of nucleated BM cells in the irradiated mice was also elevated in the PLX-RAD treated mice. Our study suggests that IM treatment with PLX-RAD cells may serve as a highly effective "off the shelf" therapy to treat BM failure following total body exposure to high doses of radiation. The results suggest that similar treatments may be beneficial also for clinical conditions associated with severe BM aplasia and pancytopenia. PMID:23823334

  17. Optimizing adherence to antiretroviral therapy

    PubMed Central

    Sahay, Seema; Reddy, K. Srikanth; Dhayarkar, Sampada

    2011-01-01

    HIV has now become a manageable chronic disease. However, the treatment outcomes may get hampered by suboptimal adherence to ART. Adherence optimization is a concrete reality in the wake of ‘universal access’ and it is imperative to learn lessons from various studies and programmes. This review examines current literature on ART scale up, treatment outcomes of the large scale programmes and the role of adherence therein. Social, behavioural, biological and programme related factors arise in the context of ART adherence optimization. While emphasis is laid on adherence, retention of patients under the care umbrella emerges as a major challenge. An in-depth understanding of patients’ health seeking behaviour and health care delivery system may be useful in improving adherence and retention of patients in care continuum and programme. A theoretical framework to address the barriers and facilitators has been articulated to identify problematic areas in order to intervene with specific strategies. Empirically tested objective adherence measurement tools and approaches to assess adherence in clinical/ programme settings are required. Strengthening of ART programmes would include appropriate policies for manpower and task sharing, integrating traditional health sector, innovations in counselling and community support. Implications for the use of theoretical model to guide research, clinical practice, community involvement and policy as part of a human rights approach to HIV disease is suggested. PMID:22310817

  18. Rapidly Self-Renewing Human Multipotent Marrow Stromal Cells (hMSC) Express Sialyl Lewis X and Actively Adhere to Arterial Endothelium in a Chick Embryo Model System

    PubMed Central

    McFerrin, Harris E.; Olson, Scott D.; Gutschow, Miriam V.; Semon, Julie A.; Sullivan, Deborah E.; Prockop, Darwin J.

    2014-01-01

    Background There have been conflicting observations regarding the receptors utilized by human multipotent mesenchymal bone marrow stromal cells (hMSC) to adhere to endothelial cells (EC). To address the discrepancies, we performed experiments with cells prepared with a standardized, low-density protocol preserving a sub-population of small cells that are rapidly self-renewing. Methods Sialyl Lewis X (SLeX) and α4 integrin expression were determined by flow cytometry. Fucosyltransferase expression was determined by quantitative realtime RT-PCR. Cell adhesion assays were carried out with a panel of endothelial cells from arteries, veins and the microvasculature in vitro. In vivo experiments were performed to determine single cell interactions in the chick embryo chorioallantoic membrane (CAM). The CAM is a well-characterized respiratory organ allowing for time-lapse image acquisition of large numbers of cells treated with blocking antibodies against adhesion molecules expressed on hMSC. Results hMSC expressed α4 integrin, SLeX and fucosyltransferase 4 and adhered to human EC from arteries, veins and the microvasculature under static conditions in vitro. In vivo, hMSC rolled on and adhered to arterioles in the chick embryo CAM, whereas control melanoma cells embolized. Inhibition of α4 integrin and/or SLeX with blocking antibodies reduced rolling and adhesion in arterioles and increased embolism of hMSC. Conclusions The results demonstrated that rapidly self-renewing hMSC were retained in the CAM because they rolled on and adhered to respiratory arteriolar EC in an α4 integrin- and SLeX-dependent manner. It is therefore important to select cells based on their cell adhesion receptor profile as well as size depending on the intended target of the cell and the injection route. PMID:25144321

  19. pap-2-encoded fimbriae adhere to the P blood group-related glycosphingolipid stage-specific embryonic antigen 4 in the human kidney.

    PubMed Central

    Karr, J F; Nowicki, B J; Truong, L D; Hull, R A; Moulds, J J; Hull, S I

    1990-01-01

    A subtype of P fimbriae, encoded by the pap-2 gene cluster, has been analyzed for agglutination of erythrocytes and for binding to cryostat sections of the human kidney. We have demonstrated that pap-2-encoded fimbriae are capable of binding to erythrocytes from some animal species and to human erythrocytes which express globoside and the LKE (stage-specific embryonic antigen 4 [SSEA-4]) antigen. The pap-2 fimbriae bind to Bowman's capsule in the human kidney. Monoclonal antibodies directed against glycosphingolipids were used for the detection of specific P blood group-related antigens in the human kidney and on erythrocytes. Preincubation of kidney sections with monoclonal antibody MC813-70, which binds to the SSEA-4 antigen, inhibited adherence of purified pap-2-encoded fimbriae to Bowman's capsule. We suggest that one receptor for pap-2-encoded fimbriae is the antigen known as LKE (Luke) on human erythrocytes or SSEA-4 in the tissues. Images PMID:1979319

  20. Adherence of human mesenchymal stem cells on Ti and TiO2 nano-columnar surfaces fabricated by glancing angle sputter deposition

    NASA Astrophysics Data System (ADS)

    Motemani, Yahya; Greulich, Christina; Khare, Chinmay; Lopian, Michael; Buenconsejo, Pio John S.; Schildhauer, Thomas A.; Ludwig, Alfred; Köller, Manfred

    2014-02-01

    The interaction of human mesenchymal stem cells (hMSCs) with Ti and TiO2 nano-columnar surfaces fabricated using glancing angle sputter deposition was investigated. The adherence and proliferation of hMSCs on different nano-columnar surfaces, including vertical columns, slanted columns and chevrons, were examined with calcein-acetoxymethyl ester fluorescence staining and scanning electron microscopy. For comparison, adherence of hMSCs on compact, dense films was also studied. After 24 h and 7 days, adherent and viable cells were observed on both, Ti nano-columns as well as dense Ti films, which confirms the biocompatibility of these nanostructures. Very small pseudopodia with width of approximately 20-35 nm and length varying from 20 to 200 nm were observed between the nano-columns, independent of the type of the nano-columnar morphology. Large inter-column spacing and effectively increased surface area make these nanostructures promising candidates for bio-functionalization or drug loading on the surface of Ti-based implants.

  1. Activated polymorphonuclear cells increase sickle red blood cell retention in lung: role of phospholipids.

    PubMed

    Haynes, Johnson; Obiako, Boniface

    2002-01-01

    This study investigates the role of the activated polymorphonuclear cell (APMN) products on sickle red blood cell (SRBC) retention/adherence in the pulmonary circulation. Isolated rat lungs were perfused with (51)Cr-labeled normal RBCs (NRBC) or SRBCs (10% hematocrit) suspensions +/- PMNs. Specific activities of lung and perfusate were measured and retention (the number of SRBC/g lung) was calculated. SRBC retention was 3.5 times greater than NRBC retention. PMN activation was required to increase SRBC retention. Supernatants from APMN increased SRBC retention, which suggested soluble products such as oxidants, PAF, and/or leukotriene (LTB(4)) are involved. Heat inactivation of PMN NADPH oxidase had no effect on retention. Whereas neither platelet-activating factor (PAF) nor LTB(4) (secreted by APMN) increased SRBC retention, PAF+LTB(4) did. The PAF antagonist, WEB-2170, attenuated SRBC retention mediated by PAF+LTB(4) and APMNs. Similarly, zileuton (5-lipoxygenase inhibitor) attenuated APMN-mediated SRBC retention. We conclude the concomitant release of PAF and LTB(4) from APMN is involved in the initiation of microvascular occlusion by SRBCs in the perfused rat lung. PMID:11748055

  2. Pulmonary accumulation of polymorphonuclear leukocytes in the adult respiratory distress syndrome

    SciTech Connect

    Powe, J.E.; Short, A.; Sibbald, W.J.; Driedger, A.A.

    1982-11-01

    The polymorphonuclear leukocyte (PMN) plays an integral role in the development of permeability pulmonary edema associated with the adult respiratory distress syndrome (ARDS). This report describes 3 patients with ARDS secondary to systemic sepsis who demonstrated an abnormal diffuse accumulation of Indium (/sup 111/In)-labeled PMNs in their lungs, without concomitant clinical or laboratory evidence of a primary chest infection. In one patient, the accumulation of the pulmonary activity during an initial pass suggested that this observation was related to diffuse leukoaggregation within the pulmonary microvasculature. A 4th patient with ARDS was on high-dose corticosteroids at the time of a similar study, and showed no pulmonary accumulation of PMNs, suggesting a possible reason for the reported beneficial effect of corticosteroids in human ARDS.

  3. Modulation of human eosinophil polymorphonuclear leukocyte migration and function.

    PubMed Central

    Goetzl, E. J.

    1976-01-01

    Eosinophil migration toward a concentration gradient of a chemotactic factor is regulated at four levels. Diverse immunologic pathways generate stimuli with eosinophil chemotactic activity, including the complement products C5a and a fragment of C3a and the peptide products of mast cells and basophils activated by IgE-mediated reactions, such as eosinophil chemotactic factor of anaphylaxis (ECF-A) and other oligopeptides. The intrinsic preferential leukocyte activity of the chemotactic stimuli represents the second level of modulation, with ECF-A and other mast cell-derived peptides exhibiting the most selective action on eosinophils. The third level of control of eosinophil chemotaxis is composed of inactivators and inhibitors of chemotactic stimuli and is exemplified by degradation of C5a by anaphylatoxin inactivator or chemotactic factor inactivator and of ECF-A by carboxypeptidase-A or aminopeptidases. The activity of ECF-A is uniquely suppressed by equimolar quantities of its NH2- terminal tripeptide substituent, presumably by eosinophil membrane receptor competition. Factors comprising the fourth level of regulation, which alter eosinophil responsiveness to chemotactic stimuli, include the chemotactic factors themselves, through deactivation; nonchemotactic inhibitors such as the COOH-terminal tripeptide substituent of ECF-A, the neutrophil-immobilizing factor (NIF), the phagocytosis-enhancing factor Thr-Lys-Pro-Arg, and histamine at concentrations greater than 400 ng/ml; and nonchemotactic enhancing principles represented by ascorbate and by histamine at concentrations of 30 ng/ml or less. Local concentrations of eosinophils called to and immobilized at the site of a hypersenitivity reaction may express their regulatory functions by degrading the chemical mediators elaborated including histamine, slow-reacting substance of anaphylaxis (SRS-A), and platelet-activating factor (PAF) by way of their content of histaminase, arylsulfatase B, and phospholipase D, respectively. Immunologic pathways may thus provide the capability for early and specific host defense reactions with a later influx of eosinophils preventing irreversible local tissue alterations or distant organ effects. PMID:793410

  4. Crohn disease–associated adherent-invasive E. coli bacteria target mouse and human Peyer’s patches via long polar fimbriae

    PubMed Central

    Chassaing, Benoit; Rolhion, Nathalie; de Vallée, Amélie; Salim, Sa’ad Y.; Prorok-Hamon, Maelle; Neut, Christel; Campbell, Barry J.; Söderholm, Johan D.; Hugot, Jean-Pierre; Colombel, Jean-Frédéric; Darfeuille-Michaud, Arlette

    2011-01-01

    Crohn disease (CD) is a multifactorial disease in which an abnormal immune response in the gastrointestinal (GI) tract leads to chronic inflammation. The small intestine, particularly the ileum, of patients with CD is colonized by adherent-invasive E. coli (AIEC) — a pathogenic group of E. coli able to adhere to and invade intestinal epithelial cells. As the earliest inflammatory lesions are microscopic erosions of the epithelium lining the Peyer’s patches (PPs), we investigated the ability of AIEC bacteria to interact with PPs and the virulence factors involved. We found that AIEC bacteria could interact with mouse and human PPs via long polar fimbriae (LPF). An LPF-negative AIEC mutant was highly impaired in its ability to interact with mouse and human PPs and to translocate across monolayers of M cells, specialized epithelial cells at the surface of PPs. The prevalence of AIEC strains harboring the lpf operon was markedly higher in CD patients compared with controls. In addition, increased numbers of AIEC, but not LPF-deficient AIEC, bacteria were found interacting with PPs from Nod2–/– mice compared with WT mice. In conclusion, we have identified LPF as a key factor for AIEC to target PPs. This could be the missing link between AIEC colonization and the presence of early lesions in the PPs of CD patients. PMID:21339647

  5. Growth hormone activation of human monocytes for superoxide production but not tumor necrosis factor production, cell adherence, or action against Mycobacterium tuberculosis.

    PubMed Central

    Warwick-Davies, J; Lowrie, D B; Cole, P J

    1995-01-01

    We have previously demonstrated that growth hormone (GH) is a human macrophage-activating factor which primes monocytes for enhanced production of H2O2 in vitro. This report extends our observations to other monocyte functions relevant to infection. We find that GH also primes monocytes for O2- production, to a degree similar to the effect of gamma interferon. Neither macrophage-activating factor alone stimulates monocytes to release bioactive tumor necrosis factor. However, GH, unlike gamma interferon, does not synergize with endotoxin for enhanced tumor necrosis factor production. In further contrast, GH does not alter monocyte adherence or morphology, while phagocytosis and killing of Mycobacterium tuberculosis by GH-treated monocytes are also unaffected. Therefore, despite the multiplicity of the effects of GH on the immune system in vivo, its effects on human monocytes in vitro appear to be limited to priming for the release of reactive oxygen intermediates. PMID:7591064

  6. A YadA-like autotransporter, Hag 1, in Veillonella atypica is a Multivalent Hemagglutinin Involved in Adherence to Oral Streptococci, Porphyromonas gingivalis, and Human Oral Buccal Cells

    PubMed Central

    Merritt, Justin; Qi, Fengxia

    2015-01-01

    Dental biofilm development is a sequential process, and adherence between microbes and the salivary pellicle (adhesion) as well as among different microbes (co-adhesion or coaggregation) plays a critical role in building a biofilm community. The Veillonella species are among the most predominant species in the oral cavity and coaggregate with many initial, early, middle and late colonizers. Similar to oral fusobacteria, they are also considered bridging species in biofilm development. However, the mechanism of this ability has yet to be reported, due to the previous lack of a genetic transformation system in the entire genus. In this study, we used our recently discovered transformable Veillonella strain, V. atypica OK5, to probe the mechanism of coaggregation between Veillonella species and other oral bacteria. By insertional inactivation of all 8 putative hemagglutinin genes, we identified one gene, hag1, which is involved in V. atypica coaggregation with the initial colonizers Streptococcus gordonii, Streptococcus oralis and Streptococcus cristatus, and the periodontal pathogen Porphyromonas gingivalis. The hag1 mutant also abolished adherence to human buccal cells. Inhibition assays using various chemical or physiological treatments suggest different mechanisms being involved in coaggregation with different partners. The entire hag1 gene was sequenced and shown to be the largest known bacterial hemagglutinin gene. PMID:25440509

  7. Characterization of Antimicrobial Susceptibility and Its Association with Virulence Genes Related to Adherence, Invasion, and Cytotoxicity in Campylobacter jejuni and Campylobacter coli Isolates from Animals, Meat, and Humans.

    PubMed

    Lapierre, Lisette; Gatica, María A; Riquelme, Víctor; Vergara, Constanza; Yañez, José Manuel; San Martín, Betty; Sáenz, Leonardo; Vidal, Maricel; Martínez, María Cristina; Araya, Pamela; Flores, Roberto; Duery, Oscar; Vidal, Roberto

    2016-07-01

    The aim of this research was to statistically analyze the association between antimicrobial susceptibility/resistance to erythromycine, gentamicin, ciprofloxacin, and tetracycline and 11 virulence genes associated with adherence, invasion, and cytotoxicity in 528 isolates of Campylobacter coli and Campylobacter jejuni obtained from retail meat and fecal samples from food-producing animals and human patients. A high percentage of Campylobacter strains were resistant to antimicrobials, specifically ciprofloxacin and tetracycline. Moreover, we observed a wide distribution of virulence genes within the analyzed strains. C. jejuni strains were more susceptible to antimicrobials, and showed greater number of virulence genes than C. coli strains. Genes related to invasion capability, such as racR, ciaB, and pldA, were associated with antimicrobial-susceptible strains in both species. The genes cdtA and dnaJ, a citotoxin unit and an adherence-related gene, respectively, were associated with antimicrobial-resistant strains in both species. In conclusion, Campylobacter strains show a statistically significant association between antimicrobial susceptibility and the presence of virulence genes. PMID:26779841

  8. [Advances in researches on polymorphonuclear neutrophil elastase in semen].

    PubMed

    Feng, Rui-xiang; Lu, Kun-gang; Zhang, Hong-ye; Lu, Jin-chun

    2011-11-01

    Reproductive tract infection is one of the important factors of male reproduction. Polymorphonuclear neutrophil elastase (PMNE) in semen, as a marker of male reproductive tract inflammation, especially recessive infection, potentially affects male fertility. The concentration of PMNE in semen is correlated significantly not only with semen white blood cell count and seminal plasma ROS level, but also with the levels of other inflammation related cytokines, such as IL-6, IL-8, and TNF-alpha. Furthermore, PMNE has a negative impact on sperm quality by decreasing sperm motility, increasing the percentage of morphologically abnormal sperm and interfering with DNA integrity. PMNE inhibitors in semen can form a compound with PMNE, and the imbalanced proportions of the two may promote the development of chronic inflammation, and consequently lead to male infertility. At present, PMNE in semen is detected mainly by enzyme immunoassay, but this method still needs to be standardized, and the diagnostic standards to be unified. PMID:22141276

  9. Re-evaluation of the culture condition of polymorphonuclear cells for the study of apoptosis induction.

    PubMed

    Hiroi, M; Tajima, M; Shimojima, T; Kashimata, M; Miyata, T; Sakagami, H

    1998-01-01

    The culture conditions of human peripheral blood polymorphonuclear leukocytes (PMN) in the study of apoptosis induction were re-evaluated. The changes in the relative viable cell number of PMNs after tumor necrosis factor (TNF) treatment were colorimetrically investigated using a cell counting kit. The relative potency of PMNs to produce the superoxide anion (O2-) was measured as the reduction of color intensity by addition of superoxide dismutase (SOD). When the PMNs were cultured in conventional RPMI1640 medium supplemented with 10% fetal bovine serum (FBS), the stimulation effect of TNF on O2- generation by PMNs was observed only for the first 6 hours. When FBS was replaced with human serum, the effect of TNF was maintained for longer incubation periods. Prolonged incubation of PMNs spontaneously produced large DNA fragments, and the extent of DNA fragmentation was relatively smaller in human serum-containing medium. TNF, LPS, hyperthermia or potassium thiocyanate slightly accelerated the production of large DNA fragments, as well as the induction of trace amounts of internucleosomal DNA cleavage in PMNs, which became detectable only after concentration by fractional isopropanol precipitation. The present study suggests the importance of the use of human serum rather than conventional FBS for the study of apoptosis induction in PMNs. PMID:9673409

  10. Subcellular localization and heterogeneity of neutral proteases in neutrophilic polymorphonuclear leukocytes.

    PubMed

    Dewald, B; Rindler-Ludwig, R; Bretz, U; Baggiolini, M

    1975-04-01

    The subcellular localization of elastase and of neutral proteases hydrolyzing histone and casein was determined in human and rabbit polymorphonuclear leukocytes using fractionation by isopycnic centrifugation. Granule-rich fractions obtained by this technique were extracted and analyzed by acrylamide gel electrophoresis, and proteolytic activity on the gels was demonstrated by staining with either N-acetyl-D,L-alanine alpha-naphthyl ester or naphthol AS-D acetate as substrate. In both species, all neutral proteases assayed were found to be localized exclusively in the azurophil granules. Specific activities were about 10-30 times higher in human than in rabbit preparations. In extracts of human azurophil granules up to 10 proteins exhibiting esterolytic activity could be demonstrated after electrophoretic separation. Three major and two or three minor components of these esterases were shown to possess elastase activity. Similar zymograms prepared with extracts from rabbit azurophil granules revealed only one major elastase band. The electrophoretic analysis further showed that the most strongly cationic proteins of both human and rabbit PMNs were also confined to the azurophil granules. PMID:236354

  11. Polymorphonuclear neutrophils in periodontitis and their possible modulation as a therapeutic approach.

    PubMed

    Nicu, Elena A; Loos, Bruno G

    2016-06-01

    The main focus of this review is polymorphonuclear neutrophilic granulocytes. Polymorphonuclear neutrophils play a pivotal role in normal host resistance to subgingival dental-plaque biofilm. Both hyper- and hypo-responsiveness of the immune system toward the microbial challenge in periodontitis have been described. We review polymorphonuclear neutrophil physiology with emphasis on the role of neutrophil functions and dysfunctions in periodontitis. Text boxes are given at the end of each subsection, which present the current knowledge on neutrophil-modulating agents as a potential therapeutic approach in periodontitis. PMID:27045435

  12. Effect of diacetylrhein on the phagocytosis of polymorphonuclear leucocytes and its influence on the biosynthesis of hyaluronate in synovial cells.

    PubMed

    Schöngen, R N; Giannetti, B M; van de Leur, E; Reinards, R; Greiling, H

    1988-05-01

    1. The influence of diacetylrhein on the luminol-induced chemiluminescence of zymosan-activated polymorphonuclear leucocytes (PMNL) was investigated. At a concentration of 4 x 10(-5) mol/l diacetylrhein an inhibition of about 40% was found. 2. A model for the degradation of hyaline cartilage by frustrated phagocytosis was developed, in which human polymorphonuclear leucocytes cause a release of glycosaminoglycan peptides from hyaline cartilage slices (bovine nasal septum). We observed a 20% inhibition of this release at a concentration of 10(-4) mol/l diacetylrhein. 3. Human synovial fibroblasts synthesize the glycosaminoglycan hyaluronate. As a parameter of the rate of hyaluronate synthesis we measured the incorporation of 14C-glucosamine into hyaluronate. At a concentration of 2 x 10(-4) mol/l diacetylrhein a 4-fold increase of 14C-glucosamine incorporation in the membrane fraction of the synovial cells (tryptic fraction) and a 1.6-fold elevation of glucosamine release into the medium was measured. The synovial fibroblasts show a higher (1.5-fold) glucose consumption and lactate production in the presence of diacetylrhein (2 x 10(-4) mol/l). PMID:3415721

  13. Contributions of NanI Sialidase to Caco-2 Cell Adherence by Clostridium perfringens Type A and C Strains Causing Human Intestinal Disease

    PubMed Central

    Li, Jihong

    2014-01-01

    Previous studies showed that Clostridium perfringens type D animal disease strain CN3718 uses NanI sialidase for adhering to enterocyte-like Caco-2 cells. The current study analyzed whether NanI is similarly important when type A and C human intestinal disease strains attach to Caco-2 cells. A PCR survey determined that the nanI gene was absent from typical type A food poisoning (FP) strains carrying a chromosomal enterotoxin (CPE) gene or the genetically related type C Darmbrand (Db) strains. However, the nanI gene was present in type A strains from healthy humans, type A strains causing CPE-associated antibiotic-associated diarrhea (AAD) or sporadic diarrhea (SD), and type C Pig-Bel strains. Consistent with NanI sialidase being the major C. perfringens sialidase when produced, FP and Db strains had little supernatant sialidase activity compared to other type A or C human intestinal strains. All type A and C human intestinal strains bound to Caco-2 cells, but NanI-producing strains had higher attachment levels. When produced, NanI can contribute to host cell attachment of human intestinal disease strains, since a nanI null mutant constructed in type A SD strain F4969 had lower Caco-2 cell adhesion than wild-type F4969 or a complemented strain. Further supporting a role for NanI in host cell attachment, sialidase inhibitors reduced F4969 adhesion to Caco-2 cells. Collectively, these results suggest that NanI may contribute to the intestinal attachment and colonization needed for the chronic diarrhea of CPE-associated AAD and SD, but this sialidase appears to be dispensable for the acute pathogenesis of type A FP or type C enteritis necroticans. PMID:25135687

  14. A direct assessment of human prion adhered to steel wire using real-time quaking-induced conversion.

    PubMed

    Mori, Tsuyoshi; Atarashi, Ryuichiro; Furukawa, Kana; Takatsuki, Hanae; Satoh, Katsuya; Sano, Kazunori; Nakagaki, Takehiro; Ishibashi, Daisuke; Ichimiya, Kazuko; Hamada, Masahisa; Nakayama, Takehisa; Nishida, Noriyuki

    2016-01-01

    Accidental transmission of prions during neurosurgery has been reported as a consequence of re-using contaminated surgical instruments. Several decontamination methods have been studied using the 263K-hamster prion; however, no studies have directly evaluated human prions. A newly developed in vitro amplification system, designated real-time quaking-induced conversion (RT-QuIC), has allowed the activity of abnormal prion proteins to be assessed within a few days. RT-QuIC using human recombinant prion protein (PrP) showed high sensitivity for prions as the detection limit of our assay was estimated as 0.12 fg of active prions. We applied this method to detect human prion activity on stainless steel wire. When we put wires contaminated with human Creutzfeldt-Jakob disease brain tissue directly into the test tube, typical PrP-amyloid formation was observed within 48 hours, and we could detect the activity of prions at 50% seeding dose on the wire from 10(2.8) to 10(5.8) SD50. Using this method, we also confirmed that the seeding activities on the wire were removed following treatment with NaOH. As seeding activity closely correlated with the infectivity of prions using the bioassay, this wire-QuIC assay will be useful for the direct evaluation of decontamination methods for human prions. PMID:27112110

  15. A direct assessment of human prion adhered to steel wire using real-time quaking-induced conversion

    PubMed Central

    Mori, Tsuyoshi; Atarashi, Ryuichiro; Furukawa, Kana; Takatsuki, Hanae; Satoh, Katsuya; Sano, Kazunori; Nakagaki, Takehiro; Ishibashi, Daisuke; Ichimiya, Kazuko; Hamada, Masahisa; Nakayama, Takehisa; Nishida, Noriyuki

    2016-01-01

    Accidental transmission of prions during neurosurgery has been reported as a consequence of re-using contaminated surgical instruments. Several decontamination methods have been studied using the 263K-hamster prion; however, no studies have directly evaluated human prions. A newly developed in vitro amplification system, designated real-time quaking-induced conversion (RT-QuIC), has allowed the activity of abnormal prion proteins to be assessed within a few days. RT-QuIC using human recombinant prion protein (PrP) showed high sensitivity for prions as the detection limit of our assay was estimated as 0.12 fg of active prions. We applied this method to detect human prion activity on stainless steel wire. When we put wires contaminated with human Creutzfeldt–Jakob disease brain tissue directly into the test tube, typical PrP-amyloid formation was observed within 48 hours, and we could detect the activity of prions at 50% seeding dose on the wire from 102.8 to 105.8 SD50. Using this method, we also confirmed that the seeding activities on the wire were removed following treatment with NaOH. As seeding activity closely correlated with the infectivity of prions using the bioassay, this wire-QuIC assay will be useful for the direct evaluation of decontamination methods for human prions. PMID:27112110

  16. Release of leukotriene C4 (LTC4) from human eosinophils following adherence to IgE- and IgG-coated schistosomula of Schistosoma mansoni.

    PubMed Central

    Moqbel, R; Macdonald, A J; Cromwell, O; Kay, A B

    1990-01-01

    The release of leukotriene C4 (LTC4) from human low-density eosinophils following adherence to live or formalin-fixed schistosomula of Schistosoma mansoni coated with parasite-specific IgE or IgG obtained from pooled human anti-S. mansoni serum has been studied. IgE-rich fractions were obtained after fractionation of pooled immune sera on fast-protein liquid chromatography (FPLC; polyanion SI-17 column) and were identified by parasite-specific RAST. Contaminating IgG was removed by adsorption on a Staphylococcus aureus-protein A affinity column. IgG-rich FPLC fractions were identified by a specific ELISA assay. IgG-dependent activities were confirmed by protein A adsorption. Low-density eosinophils adhered to live and formalin-fixed schistosomula coated with specific antisera and released 11.7 +/- 2.7 and 16.5 +/- 3.5 pmoles of LTC4/10(6) cells, respectively. LTC4 release induced by A23187 (5 x 10(-6) M) from the same cells was 80 +/- 24 pmoles/10(6) cells and 9.9 +/- 1 pmoles/10(6) cells in the presence of Sepharose particles (CNBr-activated 4B beads) covalently coated with normal human IgG. Fixed schistosomula coated with FPLC-purified IgE and IgG gave 7.6 +/- 0.4 and 6.0 +/- 0.1 pmoles of LTC4 per 10(6) low-density eosinophils, respectively. The same IgE- and IgG-rich fractions induced eosinophil-mediated cytotoxicity of live schistosomula in vitro. Removal of IgE by an anti-IgE affinity column abolished both the IgE-dependent release of LTC4 and the in vitro killing of larvae. Conversely, IgG-dependent activities were abolished by protein A, but not anti-IgE, adsorption. Normal density eosinophils generated undetectable amounts of LTC4 when incubated with IgE-coated schistosomula, whereas with IgG-coated larvae 4.6 pmoles/10(6) cells were obtained. Following preincubation with platelet-activating factor (PAF) (10(-7) M) and leukotriene B4 (LTB4) (10(-7) M), normal density eosinophils released LTC4 when in contact with larvae coated with antigen-specific Ig

  17. Group A Streptococcus Modulates Host Inflammation by Manipulating Polymorphonuclear Leukocyte Cell Death Responses.

    PubMed

    Tsatsaronis, James A; Ly, Diane; Pupovac, Aleta; Goldmann, Oliver; Rohde, Manfred; Taylor, Jude M; Walker, Mark J; Medina, Eva; Sanderson-Smith, Martina L

    2015-01-01

    Polymorphonuclear leukocyte (PMN) cell death strongly influences the resolution of inflammatory episodes, and may exacerbate adverse pathologies in response to infection. We investigated PMN cell death mechanisms following infection by virulent group A Streptococcus (GAS). Human PMNs were infected in vitro with a clinical, virulent GAS isolate and an avirulent derivative strain, and compared for phagocytosis, the production of reactive oxygen species (ROS), mitochondrial membrane depolarization and apoptotic markers. C57BL/6J mice were then infected, in order to observe the effects on murine PMNs in vivo. Human PMNs phagocytosed virulent GAS less efficiently, produced less ROS and underwent reduced mitochondrial membrane depolarization compared with phagocytosis of avirulent GAS. Morphological and biochemical analyses revealed that PMNs infected with avirulent GAS exhibited nuclear fragmentation and caspase-3 activation consistent with an anti-inflammatory apoptotic phenotype. Conversely, virulent GAS induced PMN vacuolization and plasma membrane permeabilization, leading to a necrotic form of cell death. Infection of the mice with virulent GAS engendered significantly higher systemic pro-inflammatory cytokine release and localized infiltration of murine PMNs, with cells associated with virulent GAS infection exhibiting reduced apoptotic potential. Avirulent GAS infection was associated with lower levels of proinflammatory cytokines and tissue PMN apoptosis. We propose that the differences in PMN cell death mechanisms influence the inflammatory responses to infection by GAS. PMID:25997401

  18. Vascular cell adhesion molecule-1 and the integrin VLA-4 mediate adhesion of human B cell precursors to cultured bone marrow adherent cells.

    PubMed Central

    Ryan, D H; Nuccie, B L; Abboud, C N; Winslow, J M

    1991-01-01

    Adhesion of B cell precursors to accessory cells in the bone marrow microenvironment may be required for normal early B cell development. Human bone marrow B cell precursors adhere more avidly than mature B cells to bone marrow-derived fibroblasts. To determine the mechanism of this adhesion, expression of adhesion proteins on human B precursor cells and cell lines was measured by flow cytometry. The very late antigen (VLA) integrins VLA-4 and VLA-5 were the only adhesion proteins expressed at higher levels in B cell precursors than mature B cells. Antibodies to the alpha and beta chains of VLA-4, but not VLA-5, significantly blocked binding to bone marrow-derived fibroblasts of immature B cells and cell lines. Although fibronectin is a ligand for VLA-4, anti-fibronectin antibody and a soluble fibronectin fragment containing the VLA-4 binding domain did not block adhesion, suggesting that VLA-4 is involved in adhesion of B cell precursors, but not as a fibronectin receptor. Vascular cell adhesion molecule-1 (VCAM-1), the other known counterreceptor for VLA-4, was identified on bone marrow-derived fibroblasts, and anti-VCAM-1 significantly blocked adhesion of normal B cell precursors to bone marrow-derived fibroblasts, indicating that VLA-4/VCAM-1 interactions are important in adhesion of B cell precursors to the bone marrow microenvironment. Images PMID:1715889

  19. Effects of lead on the killing mechanisms of polymorphonuclear leukocytes

    SciTech Connect

    Silberstein, C.F.

    1984-01-01

    The effects of lead on the killing mechanisms of rat polymorphonuclear leukocytes (PMN) were investigated, using male Long-Evans rats exposed to 1% lead acetate in the drinking water for varying periods of time to achieve blood lead levels ranging from 20-200 ..mu..g/dl. Studies of PMN bacterial and fungal killing activity, chemotaxis and phagocytosis demonstrated that: 1) bactericidal activity of PMN from rats exposed to lead was not altered; 2) chemotactic activity remained within normal limits; 3) the phagocytic ability of the PMN also remained unaltered. In addition to these normal findings, one major abnormality was demonstrated: a significant decrease in the ability of PMN from rats exposed to lead to kill Candida albicans. This defect was not related to age or to length of exposure. It could not be produced by addition of lead to the test system in vitro. Further investigation revealed significant decreases in PMN glucose-6-phosphate dehydrogenase, catalase, and myeloperoxidase activities. These data support two possible mechanisms for the abnormal fungicidal activity of PMN from lead-exposed rats: decrease in ability to reduce oxygen to active metabolites, or reduction in myeloperoxidase activity due to diminshed synthesis of the heme moiety required for its function.

  20. Role of polymorphonuclear leukocytes in silica-induced pulmonary fibrosis.

    PubMed Central

    Adamson, I. Y.; Bowden, D. H.

    1984-01-01

    Silicosis is usually attributed to fibroblast stimulation by secretion of damaged alveolar macrophages (AMs), but the role of polymorphonuclear leukocytes (PMNs) and of continuing cell injury in the pathogenesis has not been fully studied. Mice given intratracheal injections of 2 mg of silica received 3H-thymidine 1 hour before death at intervals to 20 weeks. Cellular populations and lysosomal content of lavage fluids were correlated with morphology, DNA synthesis, and collagen content of the lung. The initial response involved rapid PMN and AM recruitment to the alveoli. Some free particles crossed Type 1 epithelial cells, and silica was found in interstitial macrophages. Focal Type 1 cell damage was rapidly repaired by Type 2 cell proliferation. Although PMN numbers dropped after a few days, they never reached control levels and rose again after 8 weeks; the number of AMs fell to control values from 2 to 8 weeks, then increased again. Glucosaminidase and glucuronidase levels in the lavage fluid were much higher than control levels throughout the study. Increased DNA synthesis by interstitial cells occurred from 2 days to 20 weeks; increased collagen synthesis was found from 4 weeks onward. The continuing inflammatory response of the lung to silica suggests may contribute to fibroblastic stimulation. Images Figure 3 Figure 5 Figure 6 PMID:6486244

  1. Role of polymorphonuclear leukocytes in silica-induced pulmonary fibrosis

    SciTech Connect

    Adamson, I.Y.; Bowden, D.H.

    1984-10-01

    Silicosis is usually attributed to fibroblast stimulation by secretion of damaged alveolar macrophages (AMs), but the role of polymorphonuclear leukocytes (PMNs) and of continuing cell injury in the pathogenesis has not been fully studied. Mice given intratracheal injections of 2 mg of silica received 3H-thymidine 1 hour before death at intervals to 20 weeks. Cellular populations and lysosomal content of lavage fluids were correlated with morphology, DNA synthesis, and collagen content of the lung. The initial response involved rapid PMN and AM recruitment to the alveoli. Some free particles crossed Type 1 epithelial cells, and silica was found in interstitial macrophages. Focal Type 1 cell damage was rapidly repaired by Type 2 cell proliferation. Although PMN numbers dropped after a few days, they never reached control levels and rose again after 8 weeks; the number of AMs fell to control values from 2 to 8 weeks, then increased again. Glucosaminidase and glucuronidase levels in the lavage fluid were much higher than control levels throughout the study. Increased DNA synthesis by interstitial cells occurred from 2 days to 20 weeks; increased collagen synthesis was found from 4 weeks onward. The continuing inflammatory response of the lung to silica suggests may contribute to fibroblastic stimulation.

  2. Superoxide-forming NADPH oxidase preparation of pig polymorphonuclear leucocyte.

    PubMed Central

    Wakeyama, H; Takeshige, K; Takayanagi, R; Minakami, S

    1982-01-01

    A phagocytic vesicle fraction with high NADPH-dependent superoxide-forming activity was obtained in large quantity from pig blood polymorphonuclear leucocytes, phagocytosing oil droplets in the presence of cyanide. The activity of the homogenate of the phagocytosing cells was 40 times that of the resting cells, and 70% of the activity in the homogenate was recovered in the phagocytic vesicle fraction. Essentially all of the superoxide-forming activity was extracted by repeated extraction with a mixture containing deoxycholate and Tween 20. The extract had a superoxide-forming activity of 1 mumol/min per mg of protein with NADPH, and one-fifth of this with NADH, Km values being similar to those of the vesicle fraction (40 microM for NADPH and 400 microM for NADH). A stoichiometric relationship of 1:2 for NADPH oxidation and superoxide formation was obtained, in agreement with the reaction NADPH +2O2 leads to NADP+ + 2O2 -. + H+. The activity of the extract was enhanced 2-fold by the addition of FAD, suggesting that the flavin is a component of the enzyme system. The Km value for FAD was 0.077 microM. The activities in both vesicle fraction and extract were labile even on refrigeration, but could be kept for several months at -70 degrees C. PMID:6293459

  3. AHCC Activation and Selection of Human Lymphocytes via Genotypic and Phenotypic Changes to an Adherent Cell Type: A Possible Novel Mechanism of T Cell Activation

    PubMed Central

    Olamigoke, Loretta; Mansoor, Elvedina; Mann, Vivek; Ellis, Ivory; Okoro, Elvis; Wakame, Koji; Fuji, Hajime; Kulkarni, Anil; Francoise Doursout, Marie; Sundaresan, Alamelu

    2015-01-01

    Active Hexose Correlated Compound (AHCC) is a fermented mushroom extract and immune supplement that has been used to treat a wide range of health conditions. It helps in augmentation of the natural immune response and affects immune cell activation and outcomes. The goal of this project was to study and understand the role and mechanisms of AHCC supplementation in the prevention of immunosuppression through T cell activation. The method described here involves “in vitro” culturing of lymphocytes, exposing them to different concentrations of AHCC (0 μg/mL, 50 μg/mL, 100 μg/mL, 250 μg/mL, and 500 μg/mL) at 0 hours. Interestingly, clumping and aggregation of the cells were seen between 24 and 72 hours of incubation. The cells lay down extracellular matrix, which become adherent, and phenotypical changes from small rounded lymphocytes to large macrophage-like, spindle shaped, elongated, fibroblast-like cells even beyond 360 hours were observed. These are probably translated from genotypic changes in the cells since the cells propagate for at least 3 to 6 generations (present observations). RNA isolated was subjected to gene array analysis. We hypothesize that cell adhesion is an activation and survival pathway in lymphocytes and this could be the mechanism of AHCC activation in human lymphocytes. PMID:26788109

  4. AHCC Activation and Selection of Human Lymphocytes via Genotypic and Phenotypic Changes to an Adherent Cell Type: A Possible Novel Mechanism of T Cell Activation.

    PubMed

    Olamigoke, Loretta; Mansoor, Elvedina; Mann, Vivek; Ellis, Ivory; Okoro, Elvis; Wakame, Koji; Fuji, Hajime; Kulkarni, Anil; Francoise Doursout, Marie; Sundaresan, Alamelu

    2015-01-01

    Active Hexose Correlated Compound (AHCC) is a fermented mushroom extract and immune supplement that has been used to treat a wide range of health conditions. It helps in augmentation of the natural immune response and affects immune cell activation and outcomes. The goal of this project was to study and understand the role and mechanisms of AHCC supplementation in the prevention of immunosuppression through T cell activation. The method described here involves "in vitro" culturing of lymphocytes, exposing them to different concentrations of AHCC (0 μg/mL, 50 μg/mL, 100 μg/mL, 250 μg/mL, and 500 μg/mL) at 0 hours. Interestingly, clumping and aggregation of the cells were seen between 24 and 72 hours of incubation. The cells lay down extracellular matrix, which become adherent, and phenotypical changes from small rounded lymphocytes to large macrophage-like, spindle shaped, elongated, fibroblast-like cells even beyond 360 hours were observed. These are probably translated from genotypic changes in the cells since the cells propagate for at least 3 to 6 generations (present observations). RNA isolated was subjected to gene array analysis. We hypothesize that cell adhesion is an activation and survival pathway in lymphocytes and this could be the mechanism of AHCC activation in human lymphocytes. PMID:26788109

  5. Scalable expansion of human induced pluripotent stem cells in the defined xeno-free E8 medium under adherent and suspension culture conditions☆

    PubMed Central

    Wang, Ying; Chou, Bin-Kuan; Dowey, Sarah; He, Chaoxia; Gerecht, Sharon; Cheng, Linzhao

    2015-01-01

    Large-scale production of human induced pluripotent stem cells (hiPSCs) by robust and economic methods has been one of the major challenges for translational realization of hiPSC technology. Here we demonstrate a scalable culture system for hiPSC expansion using the E8 chemically defined and xeno-free medium under either adherent or suspension conditions. To optimize suspension conditions guided by a computational simulation, we developed a method to efficiently expand hiPSCs as undifferentiated aggregates in spinner flasks. Serial passaging of two different hiPSC lines in the spinner flasks using the E8 medium preserved their normal karyotype and expression of undifferentiated state markers of TRA-1–60, SSEA4, OCT4, and NANOG. The hiPSCs cultured in spinner flasks for more than 10 passages not only could be remained pluripotent as indicated by in vitro and in vivo assays, but also could be efficiently induced toward mesodermal and hematopoietic differentiation. Furthermore, we established a xeno-free protocol of single-cell cryopreservation and recovery for the scalable production of hiPSCs in spinner flasks. This system is the first to enable an efficient scale-up bioprocess in completely xeno-free condition for the expansion and cryopreservation of hiPSCs with the quantity and quality compliant for clinical applications. PMID:23973800

  6. The Collagen-Binding Protein Cnm Is Required for Streptococcus mutans Adherence to and Intracellular Invasion of Human Coronary Artery Endothelial Cells ▿

    PubMed Central

    Abranches, Jacqueline; Miller, James H.; Martinez, Alaina R.; Simpson-Haidaris, Patricia J.; Burne, Robert A.; Lemos, José A.

    2011-01-01

    Streptococcus mutans is considered the primary etiologic agent of dental caries, a global health problem that affects 60 to 90% of the population, and a leading causative agent of infective endocarditis. It can be divided into four different serotypes (c, e, f, and k), with serotype c strains being the most common in the oral cavity. In this study, we demonstrate that in addition to OMZ175 and B14, three other strains (NCTC11060, LM7, and OM50E) of the less prevalent serotypes e and f are able to invade primary human coronary artery endothelial cells (HCAEC). Invasive strains were also significantly more virulent than noninvasive strains in the Galleria mellonella (greater wax worm) model of systemic disease. Interestingly, the invasive strains carried an additional gene, cnm, which was previously shown to bind to collagen and laminin in vitro. Inactivation of cnm rendered the organisms unable to invade HCAEC and attenuated their virulence in G. mellonella. Notably, the cnm knockout strains did not adhere to HCAEC as efficiently as the parental strains did, indicating that the loss of the invasion phenotype observed for the mutants was linked to an adhesion defect. Comparisons of the invasive strains and their respective cnm mutants did not support a correlation between biofilm formation and invasion. Thus, Cnm is required for S. mutans invasion of endothelial cells and possibly represents an important virulence factor of S. mutans that may contribute to cardiovascular infections and pathologies. PMID:21422186

  7. Harvesting the noncirculating pool of polymorphonuclear leukocytes in rats by hetastarch exchange transfusion (HET): yield and functional assessment

    SciTech Connect

    Williams, J.H. Jr.; Moser, K.M.; Ulich, T.; Cairo, M.S.

    1987-11-01

    Isolation of polymorphonuclear leukocytes (PMN) provides an opportunity to study PMN activity in vitro and to label PMN for study of in vivo kinetics. However, simple phlebotomy (SP) of a small animal frequently yields too few PMN for in vitro handling, while PMN harvested from an induced-peritonitis may not accurately reflect PMN in a less stimulated state. We report a novel method of harvesting PMN from the circulation of rats, using hetastarch exchange transfusion (HET), which is both time and animal sparing. HET harvested 8-fold more PMN than SP. In vitro cell function was examined with assays of adherence, chemotaxis, bacterial killing, and superoxide generation. No significant (p less than 0.05) difference was found between PMN obtained by HET and pooled-PMN obtained by SP. In vivo function was examined following labeling with indium 111-oxine. The kinetics pattern described suggested normal migratory activity when compared to previous reports. The data demonstrate that rats possess a relatively large, noncirculating pool of PMN which is readily accessible by HET.

  8. Patient adherence to three dose completion of the quadrivalent human papillomavirus (HPV) vaccine in a private practice.

    PubMed

    Rubin, Rochelle F; Kuttab, Huda-Marie; Rihani, Rami S; Reutzel, Thomas J

    2012-12-01

    The human papillomavirus quadrivalent (types 6, 11, 16, and 18) recombinant vaccine is effective in preventing cervical, vulvar, vaginal and anal cancer. Maximal protection is achieved with completion of all three recommended doses. A retrospective chart review was performed to (1) assess the current vaccine series completion rates in a private practice multispecialty suburban setting and (2) identify factors associated with failure to complete the vaccine series. Chi-square and independent samples t test were used for data analysis. A total of 4,117 patients out of 10,821 eligible patients received at least one dose of the HPV vaccine between October 1, 2006 and April 30, 2010. Overall, 69.5 % (n = 2,863) of patients who received one dose of the HPV vaccine completed all three doses in a valid time frame, representing 26.5 % of all eligible patients. Patients who completed the series were younger (16.8 vs. 18.2, p < 0.05), less likely to have a sexually transmitted disease diagnosis prior to initiation of the series (57.7 vs. 69.8 %, p < 0.05), and more likely to have visited the pediatrics department compared to family medicine, internal medicine, and OB/GYN departments (75.9, 65.7, 57.0, 60.9 %, respectively, p < 0.05). Deaths, pregnancies, and adverse drug reactions were not identified as independent factors impacting completion rates. The results indicate that adolescents, patients visiting the pediatrics department and those without a prior STD diagnosis completed the vaccination series more frequently than adults managed in family medicine, internal medicine, and OB/GYN departments. PMID:22752532

  9. Improving Patient's Primary Medication Adherence

    PubMed Central

    Leguelinel-Blache, Géraldine; Dubois, Florent; Bouvet, Sophie; Roux-Marson, Clarisse; Arnaud, Fabrice; Castelli, Christel; Ray, Valérie; Kinowski, Jean-Marie; Sotto, Albert

    2015-01-01

    essential to improve outpatients’ primary medication adherence. We identified predictive factors of primary nonadherence in order to target the most eligible patients for discharge counseling sessions. Moreover, implementation of discharge counseling could be facilitated by using Health Information Technology to adapt human resources and select patients at risk of nonadherence. PMID:26469927

  10. Chemostat Enrichments of Human Feces with Resistant Starch Are Selective for Adherent Butyrate-Producing Clostridia at High Dilution Rates

    PubMed Central

    Sharp, Richard; Macfarlane, George T.

    2000-01-01

    Resistant starch (RS) enrichments were made using chemostats inoculated with human feces from two individuals at two dilution rates (D = 0.03 h−1 and D = 0.30 h−1) to select for slow- and fast-growing amylolytic communities. The fermentations were studied by analysis of short-chain fatty acids, amylase and α-glucosidase activities, and viable counts of the predominant culturable populations and the use of 16S rRNA-targeted oligonucleotide probes. Considerable butyrate was produced at D = 0.30 h−1, which corresponded with reduced branched-chain fatty acid formation. At both dilution rates, high levels of extracellular amylase activity were produced, while α-glucosidase was predominantly cell associated. Bacteroides and bifidobacteria predominated at the low dilution rate, whereas saccharolytic clostridia became more important at D = 0.30 h−1. Microscopic examination showed that within 48 h of inoculation, one particular bacterial morphotype predominated in RS enrichments at D = 0.30 h−1. This organism attached apically to RS granules and formed rosette-like structures which, with glycocalyx formation, agglomerated to form biofilm networks in the planktonic phase. Attempts to isolate this bacterium in pure culture were repeatedly unsuccessful, although a single colony was eventually obtained. On the basis of its 16S rDNA sequence, this RS-degrading, butyrate-producing organism was identified as being a previously unidentified group I Clostridium sp. A 16S rRNA-targeted probe was designed using this sequence and used to assess the abundance of the population in the enrichments. At 240 h, its contributions to total rRNA in the chemostats were 5 and 23% at D = 0.03 and 0.30 h−1, respectively. This study indicates that bacterial populations with significant metabolic potential can be overlooked using culture-based methodologies. This may provide a paradigm for explaining the discrepancy between the low numbers of butyrate-producing bacteria that are

  11. Prevention of vascular inflammation by nanoparticle targeting of adherent neutrophils

    NASA Astrophysics Data System (ADS)

    Wang, Zhenjia; Li, Jing; Cho, Jaehyung; Malik, Asrar B.

    2014-03-01

    Inflammatory diseases such as acute lung injury and ischaemic tissue injury are caused by the adhesion of a type of white blood cell--polymorphonuclear neutrophils--to the lining of the circulatory system or vascular endothelium and unchecked neutrophil transmigration. Nanoparticle-mediated targeting of activated neutrophils on vascular endothelial cells at the site of injury may be a useful means of directly inactivating neutrophil transmigration and hence mitigating vascular inflammation. Here, we report a method employing drug-loaded albumin nanoparticles, which efficiently deliver drugs into neutrophils adherent to the surface of the inflamed endothelium. Using intravital microscopy of tumour necrosis factor-α-challenged mouse cremaster post-capillary venules, we demonstrate that fluorescently tagged albumin nanoparticles are largely internalized by neutrophils adherent to the activated endothelium via cell surface Fcɣ receptors. Administration of albumin nanoparticles loaded with the spleen tyrosine kinase inhibitor, piceatannol, which blocks `outside-in' β2 integrin signalling in leukocytes, detached the adherent neutrophils and elicited their release into the circulation. Thus, internalization of drug-loaded albumin nanoparticles into neutrophils inactivates the pro-inflammatory function of activated neutrophils, thereby offering a promising approach for treating inflammatory diseases resulting from inappropriate neutrophil sequestration and activation.

  12. Interaction of Escherichia coli with Different Fimbriae and Polymorphonuclear Leukocytes

    PubMed Central

    Björkstén, Bengt; Wadström, Torkel

    1982-01-01

    The effects of Escherichia coli strains with various fimbriae on bacteria-polymorphonuclear leukocyte (PMN) interactions were studied. Strains of E. coli were cultivated at 37°C to express and at 18°C to suppress the formation of fimbriae. The presence of fimbriae was confirmed by electron microscopic studies and hemagglutination and salt aggregation tests. Fimbriated E. coli strains were more readily PMN associated than the nonfimbriated strains in the absence of opsonins, confirming the results of previous studies. However, the PMN chemiluminescence (CL) induced by the various strains in the absence of serum opsonins depended on the type of fimbriae they expressed. Strains with type 1 fimbriae expressing mannose-sensitive hemagglutination induced 5 to 15 times more CL than the same strains grown at 18°C, i.e., not expressing this type of fimbriae. For strains showing mannose-resistant hemagglutination, the differences between fimbriated and nonfimbriated variants of the same strains grown at 37 and 18°C, respectively, were less pronounced. Analysis of enterotoxigenic strains expressing colonization factor antigen I (CFA/I) fimbriae showed that these induced only 25 to 33% of the CL induced by the same E. coli strains not expressing CFA/I, whereas enterotoxigenic strains expressing CFA/II fimbriae induced 100 to 200% of the CL induced by the nonfimbriated variants. Although less CL was induced by bacteria with CFA/I fimbriae than by nonfimbriated variants, this situation was reversed when the microorganisms were opsonized. Thus, CFA/I fimbriae, while enhancing adhesion to cells, induce less activation of PMN-killing mechanisms in a serum-free environment. These findings may be relevant for the virulence in certain body sites, since CFA/I fimbriae, while facilitating adhesiveness, may protect the bacteria from PMN killing. Our findings indicate that PMN interactions with fimbriated E. coli in the host defense may be complex. Certain fimbriae may indeed be

  13. Fracture initiates systemic inflammatory response syndrome through recruiting polymorphonuclear leucocytes.

    PubMed

    Li, Haipeng; Liu, Jia; Yao, Jianhua; Zhong, Jianfeng; Guo, Lei; Sun, Tiansheng

    2016-08-01

    Fracture, a common type injury in trauma patients, often results in the development of the systemic inflammatory response syndrome (SIRS). Though the mechanism of the fracture-initiated SIRS still remains not well characterized, it is well documented that the polymorphonuclear leucocytes (PMN) play an important role in the inflammatory process. We hypothesize that fractures recruit PMN to the local tissue, which is followed by an increase in the number of peripheral PMN and initiation of SIRS. In the current study, we established a closed femoral fracture rat model. We evaluated the levels of MPO, IL-1β and CINC-1 in fractured tissue homogenate, and we measured the levels of IL-6 and IL-10, the biomarkers for systemic inflammatory response, in the rat sera. In clinical part of the study, we collected blood from patients with isolated closed femoral fractures and evaluated PMN-related chemoattractants (IL-8, IL-1β and G-CSF) and the number of peripheral PMN. We further evaluated the level of mitochondrial DNA in the local haematoma of fracture and the circulating plasma of the patients with fracture. In the animal model of closed femoral fracture, we found a significant recruitment of PMN to the local tissue after fracture, which correlates with the elevated MPO level. We also showed that the concentration of IL-1β and CINC-1 in local tissue is significantly increased and might be responsible for the PMN recruitment. Recruitment of PMN to the local tissue was accompanied with a significant increase in the systemic levels of IL-6 and IL-10 in serum. In the patients with closed femoral fracture, we observed an increase in the number of peripheral PMN and PMN-related chemoattractants, including IL-8, IL-1β and G-CSF. The level of mitochondrial DNA in the local haematoma of fracture and the circulating plasma of patients were significantly higher compared to the healthy volunteers. Our data suggest that fracture released mitochondrial DNA into the local haematoma of

  14. Enhancing adherence through education.

    PubMed

    Smrtka, Jennifer; Caon, Christina; Saunders, Carol; Becker, Brenda L; Baxter, Nancy

    2010-10-01

    The treatment of multiple sclerosis (MS) has advanced greatly since the introduction of disease-modifying therapies (DMTs) in the early 1990s. Although the DMTs have exhibited significant efficacy in relapsing-remitting MS and other forms of the disease, the degree of benefit depends heavily on patient adherence to recommended regimens. This article addresses some of the most pressing areas of unmet need in educating advanced-practice nurses, neurologists, patients, and support care partners regarding strategies that can overcome obstacles to adherence. The observations presented here are based on clinical experience with real-life cognitive, psychosocial, and cultural impediments to adherence. The article also explores the ways in which adherence may be affected by emerging therapies for MS (such as oral agents) as well as the educational needs that will arise with the further evolution of MS care. PMID:21049830

  15. Adherence to Insulin Therapy.

    PubMed

    Sarbacker, G Blair; Urteaga, Elizabeth M

    2016-08-01

    IN BRIEF Six million people with diabetes use insulin either alone or in combination with an oral medication. Many barriers exist that lead to poor adherence with insulin. However, there is an underwhelming amount of data on interventions to address these barriers and improve insulin adherence. Until pharmacological advancements create easier, more acceptable insulin regimens, it is imperative to involve patients in shared decision-making. PMID:27574371

  16. Human Placenta-Derived Adherent Cell Treatment of Experimental Stroke Promotes Functional Recovery after Stroke in Young Adult and Older Rats

    PubMed Central

    Shehadah, Amjad; Chen, Jieli; Pal, Ajai; He, Shuyang; Zeitlin, Andrew; Cui, Xu; Zacharek, Alex; Cui, Yisheng; Roberts, Cynthia; Lu, Mei; Hariri, Robert; Chopp, Michael

    2014-01-01

    Background Human Placenta-Derived Adherent Cells (PDAC®) are a novel mesenchymal-like cell population derived from normal human placental tissue. PDA-001 is a clinical formulation of PDAC® developed for intravenous administration. In this study, we investigated the efficacy of PDA-001 treatment in a rat model of transient middle cerebral artery occlusion (MCAo) in young adult (2–3 month old) and older rats (10–12 months old). Methods To evaluate efficacy and determine the optimal number of transplanted cells, young adult Wistar rats were subjected to MCAo and treated 1 day post MCAo with 1×106, 4×106 or 8×106 PDA-001 cells (i.v.), vehicle or cell control. 4×106 or 8×106 PDA-001 cells were also tested in older rats after MCAo. Treatment response was evaluated using a battery of functional outcome tests, consisting of adhesive-removal test, modified Neurological Severity Score (mNSS) and foot-fault test. Young adult rats were sacrificed 56 days after MCAo, older rats were sacrificed 29 days after MCAo, and lesion volumes were measured using H&E. Immunohistochemical stainings for bromodeoxyuridine (BrdU) and von Willebrand Factor (vWF), and synaptophysin were performed. Results In young adult rats, treatment with 4×106 PDA-001 cells significantly improved functional outcome after stroke (p<0.05). In older rats, significant functional improvement was observed with PDA-001 cell therapy in both of the 4×106 and 8×106 treatment groups. Functional benefits in young adult and older rats were associated with significant increases in the number of BrdU immunoreactive endothelial cells, vascular density and perimeter in the ischemic brain, as well as significantly increased synaptophysin expression in the ischemic border zone (p<0.05). Conclusion PDA-001 treatment significantly improved functional outcome after stroke in both young adult and older rats. The neurorestorative effects induced by PDA-001 treatment may be related to increased vascular density and

  17. Milk digesta and milk protein fractions influence the adherence of Lactobacillus gasseri R and Lactobacillus casei FMP to human cultured cells.

    PubMed

    Volstatova, Tereza; Havlik, Jaroslav; Potuckova, Miroslava; Geigerova, Martina

    2016-08-10

    Adhesion to the intestinal epithelium is considered an important feature of probiotic bacteria, which may increase their persistence in the intestine, allowing them to exert their beneficial health effect or promote the colonisation process. However, this feature might be largely dependent on the host specificity or diet. In the present study, we investigated the effect of selected milks and milk protein fractions on the ability of selected lactobacilli to adhere to the cells of an intestinal model based on co-culture Caco-2/HT29-MTX cell lines. Most milk digesta did not significantly affect bacterial adhesion except for UHT-treated milk and sheep milk. The presence of UHT-treated milk digesta reduced the adhesion of Lactobacillus gasseri R by 61% but not that of Lactobacillus casei FMP. However, sheep milk significantly increased the adherence of L. casei FMP (P < 0.05) but not of L. gasseri R. Among the protein fractions, rennet casein (RCN) and bovine serum albumin (BSA) showed reproducible patterns and strain-specific effects on bacterial adherence. While RCN reduced the adherence of L. gasseri R to <50% compared to the control, it did not have a significant effect on L. casei FMP. In contrast, BSA reduced L. casei FMP adherence to a higher extent than that of L. gasseri R. Whey protein (WH) tended to increase the adherence of both strains by 130%-180%. Recently, interactions between the host diet and its microbiota have attracted considerable interest. Our results may explain one of the aspects of the role of milk in the development of microbiota or support of probiotic supplements. Based on our data, we conclude that the persistence of probiotic strains supplemented as part of dairy food or constitutional microbiota in the gut might be affected negatively or positively by the food matrix through complex strain or concentration dependent effects. PMID:27435508

  18. Alterations of the respiratory burst of polymorphonuclear leukocytes from diabetic children. A chemiluminescence study.

    PubMed

    Kantar, A; Wilkins, G; Swoboda, B; Littarru, G P; Bertoli, E; Catassi, C; Coppa, G; Giorgi, P L

    1990-05-01

    The respiratory burst of polymorphonuclear leukocytes was investigated in 24 children with insulin dependent diabetes mellitus and 24 healthy controls. This oxygen dependent, membrane associated process generates a number of toxic oxygen metabolites which are implicated in the pathogenesis of endothelial damage. The activity of polymorphonuclear leukocytes was studied in terms of luminol amplified chemiluminescence. It was found that the resting luminol amplified chemiluminescence activity of isolated polymorphonuclear leukocytes from diabetic children was significantly higher than that of controls (342,000 +/- 174,000 cpm vs. 165,000 +/- 82,000 cpm, p less than 0.01). The addition of respiratory burst inhibitors caused a significant reduction of basal chemiluminescence (greater than 80%). When the ratio of phorbol myristate acetate stimulated activity to basal activity was calculated and used as an activation index, it was found to be significantly reduced in diabetics relative to controls (4.29 +/- 2.46 vs. 8.34 +/- 3.21, p less than 0.01). These observations suggest that increased release of toxic oxygen metabolites from polymorphonuclear leukocytes in diabetic subjects may play a role in the development of diabetic angiopathies. PMID:2166990

  19. Adherence to Sublingual Immunotherapy.

    PubMed

    Incorvaia, Cristoforo; Mauro, Marina; Leo, Gualtiero; Ridolo, Erminia

    2016-02-01

    Adherence is a major issue in any medical treatment. Allergen immunotherapy (AIT) is particularly affected by a poor adherence because a flawed application prevents the immunological effects that underlie the clinical outcome of the treatment. Sublingual immunotherapy (SLIT) was introduced in the 1990s, and the early studies suggested that adherence and compliance to such a route of administration was better than the traditional subcutaneous route. However, the recent data from manufacturers revealed that only 13% of patients treated with SLIT reach the recommended 3-year duration. Therefore, improved adherence to SLIT is an unmet need that may be achieved by various approaches. The utility of patient education and accurate monitoring during the treatment was demonstrated by specific studies, while the success of technology-based tools, including online platforms, social media, e-mail, and a short message service by phone, is currently considered to improve the adherence. This goal is of pivotal importance to fulfill the object of SLIT that is to modify the natural history of allergy, ensuring a long-lasting clinical benefit, and a consequent pharmaco-economic advantage, when patients complete at least a 3-year course of treatment. PMID:26758865

  20. A large mobility of hydrophilic molecules at the outmost layer controls the protein adsorption and adhering behavior with the actin fiber orientation of human umbilical vein endothelial cells (HUVEC).

    PubMed

    Kakinoki, Sachiro; Seo, Ji-Hun; Inoue, Yuuki; Ishihara, Kazuhiko; Yui, Nobuhiko; Yamaoka, Tetsuji

    2013-01-01

    Adhesion behaviors of human umbilical vein endothelial cells (HUVECs) are interestingly affected by the mobility of hydrophilic chains on the material surfaces. Surfaces with different molecular mobilities were prepared using ABA-type block copolymers consisting polyrotaxane (PRX) or poly(ethylene glycol) (PEG) central block (A block), and amphiphilic anchoring B blocks of poly(2-methacryloyloxyethyl phosphorylcholine-co-n-butyl methacrylate) (PMB). Two different molecular mobilities of the PRX chains were designed by using normal α-cyclodextrin (α-CD) or α-CD whose hydroxyl groups were converted to methoxy groups in a given ratio to improve its molecular mobility (PRX-PMB and OMe-PRX-PMB). The surface mobility of these materials was assessed as the mobility factor (Mf), which is measured by quartz crystal microbalance with dissipation monitoring system. HUVECs adhered on OMe-PRX-PMB surface much more than PRX-PMB and PMB-block-PEG-block-PMB (PEG-PMB) surfaces. These different HUVEC adhesions were correlated with the density of cell-binding site of adsorbed fibronectin. In addition, the alignment of the actin cytoskeleton of adhered HUVECs was strongly suppressed on the PEG-PMB, PRX-PMB, and OMe-PRX-PMB in response to the increased Mf value. Remarkably, the HUVECs adhered on the OMe-PRX-PMB surface with much less actin organization. We concluded that not only the cell adhesion but also the cellular function are regulated by the molecular mobility of the outmost material surfaces. PMID:23796033

  1. Adherence to treatment in adolescents

    PubMed Central

    Taddeo, Danielle; Egedy, Maud; Frappier, Jean-Yves

    2008-01-01

    Health care professionals must be alert to the high prevalence of low adherence to treatment during adolescence. Low adherence increases morbidity and medical complications, contributes to poorer quality of life and an overuse of the health care system. Many different factors have an impact on adherence. However, critical factors to consider in teens are their developmental stage and challenges, emotional issues and family dysfunction. Direct and indirect methods have been described to assess adherence. Eliciting an adherence history is the most useful way for clinicians to evaluate adherence, and could be the beginning of a constructive dialogue with the adolescent. Interventions to improve adherence are multiple – managing mental health issues appropriately, building a strong relationship, customizing the treatment regimen if possible, empowering the adolescent to deal with adherence issues, providing information, ensuring family and peer support, and motivational enhancement therapy. Evaluation of adherence at regular intervals should be an important aspect of health care for adolescents. PMID:19119348

  2. Defect of In Vitro Digestive Ability of Polymorphonuclear Leukocytes in Paracoccidioidomycosis

    PubMed Central

    Goihman-Yahr, Mauricio; Essenfeld-Yahr, Ervin; De Albornoz, María C.; Yarzábal, Luis; De Gómez, MaríA H.; Martín, Blanca San; Ocanto, Ana; Gil, Francisco; Convit, Jacinto

    1980-01-01

    Selected functions of polymorphonuclear leukocytes were studied in patients with paracoccidioidomycosis (South American blastomycosis), in healthy control individuals, and in patients with diseases unrelated to paracoccidioidomycosis. Patients with paracoccidioidomycosis were also evaluated by standard immunological techniques. Phagocytosis and digestion of Paracoccidioides brasiliensis yeastlike cells in vitro was estimated by an original method. It was based on the appearance of phagocytosed P. brasiliensis in preparations stained by a modification of the Papanicolaou method and examined with phase-contrast optics. Interpretation of such findings was confirmed by electron microscopy. Two strains of P. brasiliensis were used. Strain 8506 was freshly isolated from a patient. Strain Pb9 was known to be nonpathogenic and to have a peculiar cell wall composition. Yeastlike cells of the Pb9 strain were digested significantly better than those of strain 8506. A higher number of leukocytes per fungus cells led to a higher proportion of digested P. brasiliensis. Leukocytes from patients with paracoccidioidomycosis phagocytosed the fungus in a normal way, but had a significant lower ability to digest it in vitro. When individual cases were analyzed, there was an excellent correlation between clinical evolution and digestive ability of polymorphonuclear leukocytes. There was good correlation between both of these and immunological parameters. Leukocytes from all groups behaved comparably in tests of general leukocyte function and in their abilities to kill and digest Candida albicans. Our results indicate that, as a group, polymorphonuclear leukocytes from patients with paracoccidioidomycosis had a significant, rather specific, defect in their in vitro digestive capacity against phagocytosed P. brasiliensis. There was also an inverse correlation between strain pathogenicity and its susceptibility to in vitro digestion by polymorphonuclear leukocytes. Our findings are

  3. Synergistic Interaction of the Triple Combination of Amphotericin B, Ciprofloxacin, and Polymorphonuclear Neutrophils against Aspergillus fumigatus▿

    PubMed Central

    Stergiopoulou, Theodouli; Meletiadis, Joseph; Sein, Tin; Papaioannidou, Paraskevi; Walsh, Thomas J.; Roilides, Emmanuel

    2011-01-01

    Aspergillus is damaged by polymorphonuclear neutrophils (PMNs) by means of nonoxidative and oxidative mechanisms, which may be affected by antifungal and antibacterial agents that patients with invasive pulmonary aspergillosis often receive. The pharmacodynamic interactions among deoxycholate amphotericin B (AMB), ciprofloxacin (CIP), and human PMNs against Aspergillus fumigatus growth are unknown. We therefore studied the interactions between 0.032 to 2.0 μg/ml of AMB, 0.1 to 50 μg/ml of CIP at a fixed AMB/CIP ratio of 1:3.125, and PMNs from six donors at an effector-to-target (E:T) ratio of 400:1 against a clinical A. fumigatus isolate using an XTT metabolic assay and the Bliss independence pharmacodynamic-interaction model. CIP exhibited no antifungal activity alone or in combination with PMNs. Synergy was found between AMB and PMNs, with interaction indices (II) of 0.06 to 0.21; the highest interaction of 21% ± 3.6% was observed at 0.22 ± 0.09 μg/ml of AMB. The AMB and CIP (AMB+CIP) combination was synergistic (II = 0.39) at low AMB concentrations and antagonistic (II = 1.39) at high AMB concentrations, with a maximal synergistic interaction of 16% ± 3.7% observed at 0.16 ± 0.08 μg/ml of AMB. The triple combination AMB+CIP+PMNs was synergistic, with interaction indices of 0.05 to 0.20, and a maximal synergistic interaction of 24% ± 4% was observed at 0.20 ± 0.07 μg/ml of AMB. The increased percentage of Bliss synergy of the triple combination AMB+CIP+PMNs (24% ± 4%) was the product of those of the constituent double combinations AMB+PMNs (21% ± 3.6%) and AMB+CIP (16% ± 3.7%). Thus, the antifungal activity of AMB, at clinically relevant concentrations, was enhanced in combination with PMNs and CIP against A. fumigatus growth in a concentration-dependent manner. PMID:21911564

  4. Double localization of F-actin in chemoattractant-stimulated polymorphonuclear leucocytes.

    PubMed

    Lepidi, H; Benoliel, A M; Mege, J L; Bongrand, P; Capo, C

    1992-09-01

    Uniform concentrations of chemoattractants such as formylpeptides induced a morphological polarization of human polymorphonuclear leucocytes (PMNs) and a concentration of F-actin at the cell front. They also induced a transient increase in filamentous actin (F-actin) which preceded the cell shape change. We combined fluorescence microscopy and image analysis to study the localization of F-actin, as revealed by a specific probe (bodipyTM phallacidin) in suspended PMNs stimulated by chemoattractants. F-actin exhibited remarkable concentration in focal points after a 30 s exposure to 10(-8) M formylmethionyl-leucyl-phenylalanine (fMet-Leu-Phe), although no shape change of PMNs was detectable. A 10-min incubation with formylpeptide (10(-6) to 10(-9) M) induced the morphological polarization of PMNs and the appearance of a principal focus of F-actin in the cell head region and a secondary focus in the cell posterior end. The distribution of F-actin-associated fluorescence in 2D images of polarized PMNs might be due to an actual concentration of F-actin in privileged areas, to a local concentration of plasma membrane drawing filamentous actin or to variations in the cell volume. Then, we studied the distribution of a cytoplasmic marker, fluorescein diacetate and a membrane probe, TMA-DPH, in unstimulated rounded PMNs and in spherical and morphologically polarized PMNs stimulated by formylpeptide. The distribution of neither of these probes was correlated with F-actin distribution, especially in rounded PMNs stimulated 30 s with 10(-8) M fMet-Leu-Phe, suggesting that F-actin was concentrated in two foci located in the cell head region and in the cell posterior end. In addition, zymosan-activated serum induced the morphological polarization of PMNs and the appearance of two foci of filamentous actin, demonstrating that binding of formylpeptide to its specific receptor was not required for F-actin reorganization. We conclude that the accumulation of F-actin probably

  5. Quantitative investigations of the adhesiveness of circulating polymorphonuclear leucocytes to blood vessel walls

    PubMed Central

    Atherton, Anne; Born, G. V. R.

    1972-01-01

    1. A new simple method is described for quantitating the adhesiveness of circulating polymorphonuclear leucocytes, or granulocytes, to the walls of blood vessels. The cheek pouch of anaesthetized hamsters or a small part of the mesentery of anaesthetized mice were prepared for continuous microscopic observation of selected venules. Those granulocytes which moved sufficiently slowly to be individually visible were counted for 1 or 2 min periods as they rolled past a selected point on one side of a vessel. The velocity distribution of these cells was determined by analysing films. Films were used also to measure mean blood flow velocity in the venules by observing embolizing platelet thrombi induced by the iontophoretic application of adenosine diphosphate. Emigration of granulocytes into the tissues was quantitated by enumerating them in standard areas of stained histological sections. 2. In control experiments with hamster cheek pouch venules, the rolling granulocyte count usually passed through a maximum shortly after the preparation was set up and then fell to a low constant value. In mouse mesentery venules the count remained at a low approximately constant value from the beginning for at least 3 hr. 3. The mean velocity of blood flow in the venules was between 900 and 200 μ/sec. All rolling granulocytes moved much more slowly; in hamster cheek pouch venules the mean velocity was about 20 μ/sec and in mouse mesentery venules about 10 μ/sec. Around these means the velocity distribution of individual cells was narrow. 4. Rolling of granulocytes was abolished by superfusing ethylenediamine tetra-acetate (EDTA, 0·1 M) suggesting that the phenomenon depends on calcium or magnesium ions. 5. Agents were applied locally to the observed venules. Human serum albumin, trypsin or histamine in high concentrations did not affect the rolling granulocyte count. 6. The rolling granulocyte count was increased during the application of Hammarsten casein or Escherichia coli

  6. Genetic factors in exercise adoption, adherence and obesity.

    PubMed

    Herring, M P; Sailors, M H; Bray, M S

    2014-01-01

    Physical activity and exercise play critical roles in energy balance. While many interventions targeted at increasing physical activity have demonstrated efficacy in promoting weight loss or maintenance in the short term, long term adherence to such programmes is not frequently observed. Numerous factors have been examined for their ability to predict and/or influence physical activity and exercise adherence. Although physical activity has been demonstrated to have a strong genetic component in both animals and humans, few studies have examined the association between genetic variation and exercise adherence. In this review, we provide a detailed overview of the non-genetic and genetic predictors of physical activity and adherence to exercise. In addition, we report the results of analysis of 26 single nucleotide polymorphisms in six candidate genes examined for association to exercise adherence, duration, intensity and total exercise dose in young adults from the Training Interventions and Genetics of Exercise Response (TIGER) Study. Based on both animal and human research, neural signalling and pleasure/reward systems in the brain may drive in large part the propensity to be physically active and to adhere to an exercise programme. Adherence/compliance research in other fields may inform future investigation of the genetics of exercise adherence. PMID:24034448

  7. Metabolism of platelet activating factor (PAF) and lyso-PAF in polymorphonuclear granulocytes from severely burned patients.

    PubMed

    Schönfeld, W; Kasimir, S; Köller, M; Erbs, G; Müller, F E; König, W

    1990-12-01

    We studied the metabolism of 3H-platelet activating factor (PAF) and lyso-PAF in human polymorphonuclear granulocytes (PMN) from severely burned patients (n = 6) on days 1, 5, 9, 15, and 25 post-trauma. All patients suffered from a severe burn trauma of more than 30% total body surface area. Stimulation of PMN in healthy donors (n = 10) with the Ca-ionophore resulted in the conversion of 3H-lyso-PAF into PAF (18 +/- 2% of total radioactivity) and alkyl-acyl-glycero-phosphorylcholine (alkyl-acyl-GPC, 50 +/- 6%). In burned patients a significantly reduced formation of 3H-PAF was observed between days 1 and 15 post-trauma (day 9: 1 +/- 1%, p less than 0.0001). This pattern was normalized again in patients (n = 5) who survived the trauma after septic periods and was observed during the second week post-trauma. In one patient who succumbed to his injuries a sustained inhibition of PAF formation was observed up to his death. The decreased formation of PAF correlated weakly with the appearance of immature granulocytes within the analyzed cell fraction (ratio of immature cells versus PAF-formation, r = -0.55, p = 0.02).(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2258972

  8. Reconceptualizing medication adherence: six phases of dynamic adherence.

    PubMed

    Gearing, Robin E; Townsend, Lisa; MacKenzie, Michael; Charach, Alice

    2011-01-01

    Nonadherence is the Achilles' heel of effective psychiatric treatment. It affects the resolution of mental health symptoms and interferes with the assessment of treatment response. The meaning of the term adherence has evolved over time and is now associated with a variety of definitions and measurement methods. The result has been a poorly operationalized and nonstandardized term that is often interpreted differently by providers and patients. Drawing extensively from the literature, this article aims to (1) describe changes in the concept of adherence, drawing from the mental health treatment literature, (2) present a more comprehensive definition of adherence that recognizes the role of patient-provider transactions, (3) introduce dynamic adherence, a six-phase model, which incorporates the role of transactional processes and other factors that influence patients' adherence decisions, and (4) provide recommendations for providers to improve adherence as well as their relationships with patients. PMID:21790266

  9. Production of high-titer human influenza A virus with adherent and suspension MDCK cells cultured in a single-use hollow fiber bioreactor.

    PubMed

    Tapia, Felipe; Vogel, Thomas; Genzel, Yvonne; Behrendt, Ilona; Hirschel, Mark; Gangemi, J David; Reichl, Udo

    2014-02-12

    Hollow fiber bioreactors (HFBRs) have been widely described as capable of supporting the production of highly concentrated monoclonal antibodies and recombinant proteins. Only recently HFBRs have been proposed as new single-use platforms for production of high-titer influenza A virus. These bioreactors contain multiple hollow fiber capillary tubes that separate the bioreactor in an intra- and an extra-capillary space. Cells are usually cultured in the extra-capillary space and can grow to a very high cell concentration. This work describes the evaluation of the single-use hollow fiber bioreactor PRIMER HF (Biovest International Inc., USA) for production of influenza A virus. The process was setup, characterized and optimized by running a total of 15 cultivations. The HFBRs were seeded with either adherent or suspension MDCK cells, and infected with influenza virus A/PR/8/34 (H1N1), and the pandemic strain A/Mexico/4108/2009 (H1N1). High HA titers and TCID₅₀ of up to 3.87 log₁₀(HA units/100 μL) and 1.8 × 10(10)virions/mL, respectively, were obtained for A/PR/8/34 influenza strain. Influenza virus was collected by performing multiple harvests of the extra-capillary space during a virus production time of up to 12 days. Cell-specific virus yields between 2,000 and 8,000 virions/cell were estimated for adherent MDCK cells, and between 11,000 and 19,000 virions/cell for suspension MDCK.SUS2 cells. These results do not only coincide with the cell-specific virus yields obtained with cultivations in stirred tank bioreactors and other high cell density systems, but also demonstrate that HFBRs are promising and competitive single-use platforms that can be considered for commercial production of influenza virus. PMID:24269322

  10. Materials Adherence Experiment: Technology

    SciTech Connect

    Jenkins, P.P.; Landis, G.A.; Oberle, L.G.

    1997-12-31

    NASA`s Mars Pathfinder mission, launched December 4, 1996, reflects a new philosophy of exploiting new technologies to reduce mission cost and accelerate the pace of space exploration. Pathfinder will demonstrate a variety of new technologies aimed at reducing the cost of Mars exploration. Chief among these will be the demonstration of a solar-powered spacecraft on the surface of Mars. The Materials Adherence Experiment on Pathfinder was designed to measure the degradation of solar arrays due to dust settling out of the atmosphere and blocking light to the solar array, lowering the array power output.

  11. Multiple roles of Activin/Nodal, bone morphogenetic protein, fibroblast growth factor and Wnt/β-catenin signalling in the anterior neural patterning of adherent human embryonic stem cell cultures

    PubMed Central

    Lupo, Giuseppe; Novorol, Claire; Smith, Joseph R.; Vallier, Ludovic; Miranda, Elena; Alexander, Morgan; Biagioni, Stefano; Pedersen, Roger A.; Harris, William A.

    2013-01-01

    Several studies have successfully produced a variety of neural cell types from human embryonic stem cells (hESCs), but there has been limited systematic analysis of how different regional identities are established using well-defined differentiation conditions. We have used adherent, chemically defined cultures to analyse the roles of Activin/Nodal, bone morphogenetic protein (BMP), fibroblast growth factor (FGF) and Wnt/β-catenin signalling in neural induction, anteroposterior patterning and eye field specification in hESCs. We show that either BMP inhibition or activation of FGF signalling is required for effective neural induction, but these two pathways have distinct outcomes on rostrocaudal patterning. While BMP inhibition leads to specification of forebrain/midbrain positional identities, FGF-dependent neural induction is associated with strong posteriorization towards hindbrain/spinal cord fates. We also demonstrate that Wnt/β-catenin signalling is activated during neural induction and promotes acquisition of neural fates posterior to forebrain. Therefore, inhibition of this pathway is needed for efficient forebrain specification. Finally, we provide evidence that the levels of Activin/Nodal and BMP signalling have a marked influence on further forebrain patterning and that constitutive inhibition of these pathways represses expression of eye field genes. These results show that the key mechanisms controlling neural patterning in model vertebrate species are preserved in adherent, chemically defined hESC cultures and reveal new insights into the signals regulating eye field specification. PMID:23576785

  12. Multiple roles of Activin/Nodal, bone morphogenetic protein, fibroblast growth factor and Wnt/β-catenin signalling in the anterior neural patterning of adherent human embryonic stem cell cultures.

    PubMed

    Lupo, Giuseppe; Novorol, Claire; Smith, Joseph R; Vallier, Ludovic; Miranda, Elena; Alexander, Morgan; Biagioni, Stefano; Pedersen, Roger A; Harris, William A

    2013-04-01

    Several studies have successfully produced a variety of neural cell types from human embryonic stem cells (hESCs), but there has been limited systematic analysis of how different regional identities are established using well-defined differentiation conditions. We have used adherent, chemically defined cultures to analyse the roles of Activin/Nodal, bone morphogenetic protein (BMP), fibroblast growth factor (FGF) and Wnt/β-catenin signalling in neural induction, anteroposterior patterning and eye field specification in hESCs. We show that either BMP inhibition or activation of FGF signalling is required for effective neural induction, but these two pathways have distinct outcomes on rostrocaudal patterning. While BMP inhibition leads to specification of forebrain/midbrain positional identities, FGF-dependent neural induction is associated with strong posteriorization towards hindbrain/spinal cord fates. We also demonstrate that Wnt/β-catenin signalling is activated during neural induction and promotes acquisition of neural fates posterior to forebrain. Therefore, inhibition of this pathway is needed for efficient forebrain specification. Finally, we provide evidence that the levels of Activin/Nodal and BMP signalling have a marked influence on further forebrain patterning and that constitutive inhibition of these pathways represses expression of eye field genes. These results show that the key mechanisms controlling neural patterning in model vertebrate species are preserved in adherent, chemically defined hESC cultures and reveal new insights into the signals regulating eye field specification. PMID:23576785

  13. β2 integrins (CD11/18) are essential for the chemosensory adhesion and migration of polymorphonuclear leukocytes on bacterial cellulose.

    PubMed

    Kim, Gun-Dong; Lee, Seung Eun; Yang, Hana; Park, Hye Rim; Son, Gun Woo; Park, Cheung-Seog; Park, Yong Seek

    2015-05-01

    Bacterial cellulose (BC) has been studied widely for applications in biomedical materials such as prosthetic artificial blood vessels owing to its unique characteristics, which include nontoxicity and nonimmunogenicity as compared with synthetic biopolymers such as expanded polytetrafluorethylene (ePTFE). However, to date, studies on the relative effect of leukocytes on BC as a prosthetic vascular graft are insufficient. Polymorphonuclear leukocytes (PMN) play a pivotal role in early-phase immune response to bacterial or periprosthetic infection. PMN recruitment at sites of infection or inflammation mediated by various integrins such as β2 integrin family (CD11/CD18 family). Therefore, we discuss our investigations into the mechanisms by which β2 integrins-mediated chemosensory adhesion and migration of PMN on the vascular graft surface, BC. Our results show that CD11b/CD18 components mainly mediate PMN adherence on BC. CD11b/CD18 displays weak coordination with the other two α subunits (CD11a and CD11c). Furthermore, it was found that the β subunit (CD18) plays a critical role in both the adhesion and migration of N-formylmethionyl-leucyl-phenylalanine (fMLP)-stimulated PMN on BC. The activity of CD18 contrasts with that of the individual α subunits. Among these, only CD11b displayed inhibition of PMN migration on BC surfaces. PMID:25231265

  14. Adhesion of polymorphonuclear leukocytes to endothelium enhances the efficiency of detoxification of oxygen-free radicals.

    PubMed Central

    Hoover, R. L.; Robinson, J. M.; Karnovsky, M. J.

    1987-01-01

    Polymorphonuclear leukocytes can produce active oxygen species such as hydrogen peroxide and superoxide under various conditions. Because these substances can be toxic to cells, it is possible that the interaction between the circulating leukocytes and the blood vessel wall, either in normal circulation or during the acute inflammatory response, could damage the endothelial lining. Using an in vitro system of cultured endothelial cells and isolated polymorphonuclear leukocytes, we have measured the levels of detectable superoxide when neutrophils are attached to either endothelial monolayers or to plastic. Our results show that the levels of superoxide, on a per-cell basis, are lower when the neutrophils are attached to endothelium than when attached to plastic, even if the neutrophils are stimulated with phorbol myristate acetate. This is also reflected in data showing that no injury occurs to the endothelial cells, as measured by 51Cr release, under these same conditions. When endothelial cells are pretreated with an inhibitor of superoxide dismutase, diethyldithiocarbamate, the levels of superoxide detected are the same for neutrophils stimulated on plastic and those on the endothelial monolayer, suggesting that endothelial superoxide dismutase may remove a portion of the neutrophil-generated superoxide from the detection system. Further evidence for the role of endothelium in destroying superoxide is suggested by results that show that the level of detectable superoxide released from neutrophils attached to formalin-fixed endothelial monolayers is the same as that for neutrophils attached to plastic. It is important to note that with the inhibitor of superoxide dismutase present, the endothelial monolayers do not display enhanced 51Cr release under the conditions employed. When both endothelial catalase and glutathione reductase are inhibited, we detect increased 51Cr release from endothelial cells in response to stimulated neutrophils. Our results show that

  15. Dithranol modulates the leukotriene B4-induced intraepidermal accumulation of polymorphonuclear leukocytes.

    PubMed

    Chang, A; Alkemade, H; van de Kerkhof, P C

    1989-06-01

    Dithranol, with and without the addition of salicylic acid, was applied daily on normal skin according to a short contact protocol as used in the treatment of psoriasis. Sellotape stripping and epicutaneous application of leukotriene B4 (LTB4) were carried out within these pretreated areas. The challenged skin was subsequently biopsied and the intraepidermal accumulation of polymorphonuclear leukocytes (PMN) was quantified using the marker enzyme elastase. Dithranol pretreatment yielded a significant reduction of the LTB4-induced accumulation of PMN, whereas the tape stripping-induced accumulation of PMN was not affected by dithranol pretreatment. The addition of salicylic acid did not significantly enhance the effect of dithranol. PMID:2542415

  16. Leukotriene B/sub 4/ production by stimulated whole blood: comparative studies with isolated polymorphonuclear cells

    SciTech Connect

    Gresele, P.; Arnout, J.; Coene, M.C.; Deckmyn, H.; Vermylen, J.

    1986-05-29

    A new method was developed to study leukotriene B/sub 4/ (LTB/sub 4/) production by stimulated whole blood. The calcium ionophore A23187 and serum-treated zymosan induced LTB/sub 4/ production, measured by radioimmunoassay, in a dose- and time-dependent manner. The pattern of LTB/sub 4/ production by whole blood differed markedly from that observed with isolated, purified polymorphonuclear leukocytes. Higher levels of LTB/sub 4/ were reached and maintained in whole blood. The system allowed to detect drug effects on LTB/sub 4/ takes into account the complex interactions between different cell types which can modulate LTB/sub 4/ metabolism.

  17. Human neutrophil Fc receptor-mediated adhesion under flow: a hollow fibre model of intravascular arrest.

    PubMed

    D'Arrigo, C; Candal-Couto, J J; Greer, M; Veale, D J; Woof, J M

    1995-04-01

    Human polymorphonuclear cells (PMN) were found to adhere to a novel model of blood vessel wall-associated IgG. The internal surfaces of cellulose acetate hollow fibres, of comparable internal diameter to small blood vessels, were coated with normal serum human IgG, heat-aggregated IgG (HAIgG), laminin or fibrinogen. Under conditions of flow mimicking those in a small vessel, PMN were found to adhere markedly only to immunoglobulin-coated fibres. Arrest on HAIgG was inhibited by excess soluble IgG but not by bovine serum albumin (BSA), demonstrating that the adhesion was IgG-specific and presumably mediated by Fc gamma R on the PMN surface. Pre-adsorption of serum components onto HAIgG-coated fibres enhanced PMN arrest, due most probably to fixation of complement components by immobilized HAIgG, resulting in additional potential to entrap PMN via complement receptors such as CR3. Treatment of PMN with the regulatory neuropeptide substance P also enhanced adhesion to HAIgG-coated fibres and caused increased surface expression of Fc gamma RI, Fc gamma RII and Fc gamma RIII. A mouse cell line derived from L cells, hR4C6, stably transfected with human Fc gamma RII, was found to adhere under flow to HAIgG-coated fibres, whilst untransfected parent L cells did not. This adhesion was similarly inhibited by excess soluble IgG, confirming the capability of Fc gamma R to mediate cell arrest. The study strongly suggests that Fc gamma R may play an important role in intravascular PMN arrest and we speculate that in inflammatory diseases PMN may adhere via Fc gamma R to immobilized immunoglobulin on the vascular endothelium, with subsequent degranulation and tissue damage. PMID:7535210

  18. [Adherence to psychopharmacological treatment: Psychotherapeutic strategies to enhance adherence].

    PubMed

    Lencer, R; Korn, D

    2015-05-01

    Effective psychopharmacological medication with good tolerability represents the cornerstone of treatment for severe mental illness; however, the 1-year adherence rates are only approximately 50%. The term adherence emphasizes the collaborative responsibility of the clinician and the patient for a positive treatment outcome. Reasons for non-adherence are manifold and include patient-specific factors, such as self-stigmatization, lack of social and familial support, cognitive impairment and substance use besides insufficient effectiveness and the occurrence of side effects of the psychotropic drugs. To enhance adherence, both clinician and patient have to fully understand all the reasons for and against adherence to medication before a collaborative decision is made on future long-term treatment. A positive attitude towards medication critically depends on whether patients feel that the medication supports the attainment of the individual goals. PMID:25903501

  19. Improved adherence with contingency management.

    PubMed

    Rosen, Marc I; Dieckhaus, Kevin; McMahon, Thomas J; Valdes, Barbara; Petry, Nancy M; Cramer, Joyce; Rounsaville, Bruce

    2007-01-01

    Contingency management (CM) based interventions that reinforce adherence to prescribed medications have shown promise in a variety of disadvantaged populations. Fifty-six participants with histories of illicit substance use who were prescribed antiretroviral medication but evidenced suboptimal adherence during a baseline assessment were randomly assigned to 16 weeks of weekly CM-based counseling or supportive counseling, followed by 16 additional weeks of data collection and adherence feedback to providers. The CM intervention involved review of data generated by electronic pill-bottle caps that record bottle opening (MEMS) and brief substance abuse counseling. CM participants were reinforced for MEMS-measured adherence with drawings from a bowl for prizes and bonus drawings for consecutive weeks of perfect adherence. Potential total earnings averaged $800. Mean MEMS-measured adherence to the reinforced medication increased from 61% at baseline to 76% during the 16-week treatment phase and was significantly increased relative to the supportive counseling group (p = 0.01). Furthermore, mean log-transformed viral load was significantly lower in the CM group. However, by the end of the 16-week follow-up phase, differences between groups in adherence and viral load were no longer significantly different. Proportions of positive urine toxicology tests did not differ significantly between the two groups at any phase. A brief CM-based intervention was associated with significantly higher adherence and lower viral loads. Future studies should evaluate methods to extend effects for longer term benefits. PMID:17263651

  20. Antidepressant adherence after psychiatric hospitalization

    PubMed Central

    Zivin, Kara; Ganoczy, Dara; Pfeiffer, Paul N.; Miller, Erin M.; Valenstein, Marcia

    2010-01-01

    Objective Depressed patients discharged from psychiatric hospitalizations face increased risks for adverse outcomes including suicide, yet antidepressant adherence rates during this high-risk period are unknown. Using Veterans Affairs (VA) data, we assessed antidepressant adherence and predictors of poor adherence among depressed veterans following psychiatric hospitalization. Method We identified VA patients nationwide with depressive disorders who had a psychiatric hospitalization between April 1, 1999 and September 30, 2003, received antidepressant medication, and had an outpatient appointment following discharge. We calculated medication possession ratios (MPRs), a measure of medication adherence, within three and six months following discharge. We assessed patient factors associated with having lower levels of adherence (MPRs <0.8) after discharge. Results 20,931 and 23,182 patients met criteria for three and six month MPRs. The mean three month MPR was 0.79 (s.d.=0.37). The mean six month MPR was 0.66 (s.d.=0.40). Patients with poorer adherence were male, younger, non-white, and had a substance abuse disorder, but were less likely to have PTSD or other anxiety disorders. Conclusion Poor antidepressant adherence is common among depressed patients after psychiatric hospitalization. Efforts to improve adherence at this time may be critical in improving the outcomes of these high-risk patients. PMID:19609666

  1. Biologic Influences on Exercise Adherence.

    ERIC Educational Resources Information Center

    Dishman, Rod K.

    1981-01-01

    Diagnostic profiles of 362 male participants in an exercise program were analyzed to determine the biological variables between exercise adherence and symptoms of coronary disease. Findings indicated that individuals with lower metabolic capacity tended to adhere longer, to be less fit, were leaner, and began with more symptoms related to coronary…

  2. [Treatment adherence: a key element].

    PubMed

    Bastida, Guillermo; Sánchez Montes, Cristina; Aguas, Mariam

    2011-12-01

    A substantial percentage of patients fail to follow health professionals' recommendations, which affects the management of chronic diseases, reducing the effectiveness of therapeutic interventions and increasing the costs of the disease. Lack of adherence is a multidimensional phenomenon and is influenced by numerous factors that should be identified. A multiplicity of measures is available to improve adherence, such as simplifying treatment administration, but none of these measures is effective when used alone. One way of tackling lack of adherence is by identifying patients' barriers to medication and involving them in decision making. Ulcerative colitis (UC) poses a risk for lack of treatment adherence. In this disease, poor adherence correlates with poor disease control (drug effectiveness) and with higher costs. As in other chronic diseases, the causes associated with poor adherence are multiple, including psychosocial factors, the physician-patient relationship and patients' prejudices toward medication. A single dose of aminosalycylates (5-ASA) should be recommended, as this dose is as safe and effective as other regimens. However, by itself, this recommendation does not seem to improve adherence. Identifying the scale of the problem and developing strategies to involve the patient in decision making is crucial to improve treatment adherence. PMID:25443221

  3. Pathogenesis of Human Diffusely Adhering Escherichia coli Expressing Afa/Dr Adhesins (Afa/Dr DAEC): Current Insights and Future Challenges

    PubMed Central

    2014-01-01

    SUMMARY The pathogenicity and clinical pertinence of diffusely adhering Escherichia coli expressing the Afa/Dr adhesins (Afa/Dr DAEC) in urinary tract infections (UTIs) and pregnancy complications are well established. In contrast, the implication of intestinal Afa/Dr DAEC in diarrhea is still under debate. These strains are age dependently involved in diarrhea in children, are apparently not involved in diarrhea in adults, and can also be asymptomatic intestinal microbiota strains in children and adult. This comprehensive review analyzes the epidemiology and diagnosis and highlights recent progress which has improved the understanding of Afa/Dr DAEC pathogenesis. Here, I summarize the roles of Afa/Dr DAEC virulence factors, including Afa/Dr adhesins, flagella, Sat toxin, and pks island products, in the development of specific mechanisms of pathogenicity. In intestinal epithelial polarized cells, the Afa/Dr adhesins trigger cell membrane receptor clustering and activation of the linked cell signaling pathways, promote structural and functional cell lesions and injuries in intestinal barrier, induce proinflammatory responses, create angiogenesis, instigate epithelial-mesenchymal transition-like events, and lead to pks-dependent DNA damage. UTI-associated Afa/Dr DAEC strains, following adhesin-membrane receptor cell interactions and activation of associated lipid raft-dependent cell signaling pathways, internalize in a microtubule-dependent manner within urinary tract epithelial cells, develop a particular intracellular lifestyle, and trigger a toxin-dependent cell detachment. In response to Afa/Dr DAEC infection, the host epithelial cells generate antibacterial defense responses. Finally, I discuss a hypothetical role of intestinal Afa/Dr DAEC strains that can act as “silent pathogens” with the capacity to emerge as “pathobionts” for the development of inflammatory bowel disease and intestinal carcinogenesis. PMID:25278576

  4. Krüppel-Like Factor 4 Overexpression Initiates a Mesenchymal-to-Epithelial Transition and Redifferentiation of Human Pancreatic Cells following Expansion in Long Term Adherent Culture

    PubMed Central

    Docherty, Hilary M.; McGowan, Neil W. A.; Forbes, Shareen; Heremans, Yves; Forbes, Stuart J.; Heimberg, Harry; Casey, John; Docherty, Kevin

    2015-01-01

    A replenishable source of insulin-producing cells has the potential to cure type 1 diabetes. Attempts to culture and expand pancreatic β-cells in vitro have resulted in their transition from insulin-producing epithelial cells to mesenchymal stromal cells (MSCs) with high proliferative capacity but devoid of any hormone production. The aim of this study was to determine whether the transcription factor Krüppel-like factor 4 (KLF4), could induce a mesenchymal-to-epithelial transition (MET) of the cultured cells. Islet-enriched pancreatic cells, allowed to dedifferentiate and expand in adherent cell culture, were transduced with an adenovirus containing KLF4 (Ad-Klf4). Cells were subsequently analysed for changes in cell morphology by light microscopy, and for the presence of epithelial and pancreatic markers by immunocytochemistry and quantitative RT/PCR. Infection with Ad-Klf4 resulted in morphological changes, down-regulation of mesenchymal markers, and re-expression of both epithelial and pancreatic cell markers including insulin and transcription factors specific to β-cells. This effect was further enhanced by culturing cells in suspension. However, the effects of Ad-KLf4 were transient and this was shown to be due to increased apoptosis in Klf4-expressing cells. Klf4 has been recently identified as a pioneer factor with the ability to modulate the structure of chromatin and enhance reprogramming/transdifferentiation. Our results show that Klf4 may have a role in the redifferentiation of expanded pancreatic cells in culture, but before this can be achieved the off-target effects that result in increased apoptosis would need to be overcome. PMID:26457418

  5. Clustering based on adherence data

    PubMed Central

    2011-01-01

    Adherence to a medical treatment means the extent to which a patient follows the instructions or recommendations by health professionals. There are direct and indirect ways to measure adherence which have been used for clinical management and research. Typically adherence measures are monitored over a long follow-up or treatment period, and some measurements may be missing due to death or other reasons. A natural question then is how to describe adherence behavior over the whole period in a simple way. In the literature, measurements over a period are usually combined just by using averages like percentages of compliant days or percentages of doses taken. In the paper we adapt an approach where patient adherence measures are seen as a stochastic process. Repeated measures are then analyzed as a Markov chain with finite number of states rather than as independent and identically distributed observations, and the transition probabilities between the states are assumed to fully describe the behavior of a patient. The patients can then be clustered or classified using their estimated transition probabilities. These natural clusters can be used to describe the adherence of the patients, to find predictors for adherence, and to predict the future events. The new approach is illustrated and shown to be useful with a simple analysis of a data set from the DART (Development of AntiRetroviral Therapy in Africa) trial in Uganda and Zimbabwe. PMID:21385451

  6. Interaction of Bovine Peripheral Blood Polymorphonuclear Cells and Leptospira Species; Innate Responses in the Natural Bovine Reservoir Host

    PubMed Central

    Wilson-Welder, Jennifer H.; Frank, Ami T.; Hornsby, Richard L.; Olsen, Steven C.; Alt, David P.

    2016-01-01

    Cattle are the reservoir hosts of Leptospira borgpetersenii serovar Hardjo, and can also be reservoir hosts of other Leptospira species such as L. kirschneri, and Leptospira interrogans. As a reservoir host, cattle shed Leptospira, infecting other animals, including humans. Previous studies with human and murine neutrophils have shown activation of neutrophil extracellular trap or NET formation, and upregulation of inflammatory mediators by neutrophils in the presence of Leptospira. Humans, companion animals and most widely studied models of Leptospirosis are of acute infection, hallmarked by systemic inflammatory response, neutrophilia, and septicemia. In contrast, cattle exhibit chronic infection with few outward clinical signs aside from reproductive failure. Taking into consideration that there is host species variation in innate immunity, especially in pathogen recognition and response, the interaction of bovine peripheral blood polymorphonuclear cells (PMNs) and several Leptospira strains was evaluated. Studies including bovine-adapted strains, human pathogen strains, a saprophyte and inactivated organisms. Incubation of PMNs with Leptospira did induce slight activation of neutrophil NETs, greater than unstimulated cells but less than the quantity from E. coli P4 stimulated PMNs. Very low but significant from non-stimulated, levels of reactive oxygen peroxides were produced in the presence of all Leptospira strains and E. coli P4. Similarly, significant levels of reactive nitrogen intermediaries (NO2) was produced from PMNs when incubated with the Leptospira strains and greater quantities in the presence of E. coli P4. PMNs incubated with Leptospira induced RNA transcripts of IL-1β, MIP-1α, and TNF-α, with greater amounts induced by live organisms when compared to heat-inactivated leptospires. Transcript for inflammatory cytokine IL-8 was also induced, at similar levels regardless of Leptospira strain or viability. However, incubation of Leptospira strains

  7. Interaction of Bovine Peripheral Blood Polymorphonuclear Cells and Leptospira Species; Innate Responses in the Natural Bovine Reservoir Host.

    PubMed

    Wilson-Welder, Jennifer H; Frank, Ami T; Hornsby, Richard L; Olsen, Steven C; Alt, David P

    2016-01-01

    Cattle are the reservoir hosts of Leptospira borgpetersenii serovar Hardjo, and can also be reservoir hosts of other Leptospira species such as L. kirschneri, and Leptospira interrogans. As a reservoir host, cattle shed Leptospira, infecting other animals, including humans. Previous studies with human and murine neutrophils have shown activation of neutrophil extracellular trap or NET formation, and upregulation of inflammatory mediators by neutrophils in the presence of Leptospira. Humans, companion animals and most widely studied models of Leptospirosis are of acute infection, hallmarked by systemic inflammatory response, neutrophilia, and septicemia. In contrast, cattle exhibit chronic infection with few outward clinical signs aside from reproductive failure. Taking into consideration that there is host species variation in innate immunity, especially in pathogen recognition and response, the interaction of bovine peripheral blood polymorphonuclear cells (PMNs) and several Leptospira strains was evaluated. Studies including bovine-adapted strains, human pathogen strains, a saprophyte and inactivated organisms. Incubation of PMNs with Leptospira did induce slight activation of neutrophil NETs, greater than unstimulated cells but less than the quantity from E. coli P4 stimulated PMNs. Very low but significant from non-stimulated, levels of reactive oxygen peroxides were produced in the presence of all Leptospira strains and E. coli P4. Similarly, significant levels of reactive nitrogen intermediaries (NO2) was produced from PMNs when incubated with the Leptospira strains and greater quantities in the presence of E. coli P4. PMNs incubated with Leptospira induced RNA transcripts of IL-1β, MIP-1α, and TNF-α, with greater amounts induced by live organisms when compared to heat-inactivated leptospires. Transcript for inflammatory cytokine IL-8 was also induced, at similar levels regardless of Leptospira strain or viability. However, incubation of Leptospira strains

  8. Long-term multilayer adherent network (MAN) expansion, maintenance, and characterization, chemical and genetic manipulation, and transplantation of human fetal forebrain neural stem cells.

    PubMed

    Wakeman, Dustin R; Hofmann, Martin R; Redmond, D Eugene; Teng, Yang D; Snyder, Evan Y

    2009-05-01

    Human neural stem/precursor cells (hNSC/hNPC) have been targeted for application in a variety of research models and as prospective candidates for cell-based therapeutic modalities in central nervous system (CNS) disorders. To this end, the successful derivation, expansion, and sustained maintenance of undifferentiated hNSC/hNPC in vitro, as artificial expandable neurogenic micro-niches, promises a diversity of applications as well as future potential for a variety of experimental paradigms modeling early human neurogenesis, neuronal migration, and neurogenetic disorders, and could also serve as a platform for small-molecule drug screening in the CNS. Furthermore, hNPC transplants provide an alternative substrate for cellular regeneration and restoration of damaged tissue in neurodegenerative disorders such as Parkinson's disease and Alzheimer's disease. Human somatic neural stem/progenitor cells (NSC/NPC) have been derived from a variety of cadaveric sources and proven engraftable in a cytoarchitecturally appropriate manner into the developing and adult rodent and monkey brain while maintaining both functional and migratory capabilities in pathological models of disease. In the following unit, we describe a new procedure that we have successfully employed to maintain operationally defined human somatic NSC/NPC from developing fetal, pre-term post-natal, and adult cadaveric forebrain. Specifically, we outline the detailed methodology for in vitro expansion, long-term maintenance, manipulation, and transplantation of these multipotent precursors. PMID:19455542

  9. Pharmacists’ perspectives on promoting medication adherence among patients with HIV

    PubMed Central

    Kibicho, Jennifer W.; Owczarzak, Jill

    2015-01-01

    Objectives To provide pharmacists’ perspectives on medication adherence barriers for patients with human immunodeficiency virus (HIV) and to describe pharmacists’ strategies for promoting adherence to antiretroviral medications. Design Multisite, qualitative, descriptive study. Setting Four midwestern U.S. states, from August through October 2009. Participants 19 pharmacists at 10 pharmacies providing services to patients with HIV. Intervention Pharmacists were interviewed using a semistructured interview guide. Main outcome measures Barriers to medication adherence, pharmacist interventions, challenges to promoting adherence. Results Pharmacists reported a range of adherence barriers that were patient specific (e.g., cognitive factors, lack of social support), therapy related (e.g., adverse effects, intolerable medications), and structural level (e.g., strained provider relationships). They used a combination of individually tailored, patient-specific interventions that identified and resolved adherence barriers and actively anticipated and addressed potential adherence barriers. Pharmacist interventions included medication-specific education to enhance patient self-efficacy, follow-up calls to monitor adherence, practical and social support to motivate adherence, and patient referrals to other health care providers. However, the pharmacists faced internal (e.g., lack of time, lack of trained personnel) and external (e.g., insurance policies that disallowed patient enrollment in automatic prescription refill program) challenges. Conclusion Pharmacists in community settings went beyond prescription drug counseling mandated by law to provide additional pharmacy services that were tailored to the needs of patients with HIV. Given that many individuals with HIV are living longer, more research is needed on the effectiveness and cost effectiveness of pharmacists’ interventions in clinical practice, in order to inform insurance reimbursement policies. PMID

  10. Medication Adherence Measures: An Overview.

    PubMed

    Lam, Wai Yin; Fresco, Paula

    2015-01-01

    WHO reported that adherence among patients with chronic diseases averages only 50% in developed countries. This is recognized as a significant public health issue, since medication nonadherence leads to poor health outcomes and increased healthcare costs. Improving medication adherence is, therefore, crucial and revealed on many studies, suggesting interventions can improve medication adherence. One significant aspect of the strategies to improve medication adherence is to understand its magnitude. However, there is a lack of general guidance for researchers and healthcare professionals to choose the appropriate tools that can explore the extent of medication adherence and the reasons behind this problem in order to orchestrate subsequent interventions. This paper reviews both subjective and objective medication adherence measures, including direct measures, those involving secondary database analysis, electronic medication packaging (EMP) devices, pill count, and clinician assessments and self-report. Subjective measures generally provide explanations for patient's nonadherence whereas objective measures contribute to a more precise record of patient's medication-taking behavior. While choosing a suitable approach, researchers and healthcare professionals should balance the reliability and practicality, especially cost effectiveness, for their purpose. Meanwhile, because a perfect measure does not exist, a multimeasure approach seems to be the best solution currently. PMID:26539470