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1

Enzymatic Activities of Bovine Peripheral Blood Leukocytes and Milk Polymorphonuclear Neutrophils during Intramammary Inflammation Caused by Lipopolysaccharide  

PubMed Central

Leukocytes are recruited from peripheral blood into milk as part of the inflammatory response to mastitis. However, excessive accumulation of inflammatory cells alters the quality of milk and the proteases produced by polymorphonuclear neutrophils (PMNs) and macrophages may lead to mammary tissue damage. To investigate PMN recruitment and the kinetics of their intracytoplasmic enzymes in inflammation, we generated mastitis in six cows by intramammary infusion of lipopolysaccharide (LPS). Clinical signs of acute mastitis were observed in all of the cows, and normal status was resumed by 316 h. Intracytoplasmic elastase, collagenase, and cathepsin activities were measured within live cells by flow cytometry in peripheral blood leukocytes and milk PMNs before and during the inflammatory process (at 10 time points between 4 and 316 h). The proportion of immature PMNs was appreciated by CD33 surface labeling measured in flow cytometry. Leukopenia was observed in the peripheral blood 4 h postinfusion, concomitant to an increase in somatic cell counts in milk. CD33+ PMNs were preferentially recruited from the peripheral blood to milk. Enzymatic activities were detected in PMNs, lymphocytes, and monocytes at levels depending on the cell type, sample nature, and time of collection. Milk PMNs had lower enzymatic activities than peripheral blood PMNs. This study showed that milk PMNs recruited during LPS-induced experimental mastitis have an immature phenotype and significantly lower enzymatic activities than peripheral blood PMNs. This suggests that CD33, an adhesion molecule, may be involved in the egress from blood to milk and that the enzymatic contents of PMNs are partly used during this process. PMID:12093678

Prin-Mathieu, C.; Le Roux, Y.; Faure, G. C.; Laurent, F.; Béné, M. C.; Moussaoui, F.

2002-01-01

2

Heparin inhibits phagocytosis by polymorphonuclear leukocytes.  

PubMed Central

Phagocytosis of unopsonized Salmonella typhimurium 395, MR-10, opsonized Salmonella typhimurium 395 MS, and Staphylococcus epidermidis by rabbit polymorphonuclear leukocytes was inhibited by heparin at concentrations as low as 0.5 U/ml. Inhibition was dose dependent and nearly complete at 20 U/ml. Provided that heparin concentrations did not exceed 100 U/ml, inhibition could be largely reversed by washing. Heparin also reversibly inhibited the adherence of polymorphonuclear leukocytes to glass. In contrast, hexose monophosphate shunt activity of polymorphonuclear leukocytes stimulated by noningested S. typhimurium MR-10 or Streptococcus pyogenes B14 was not inhibited by heparin at concentrations as high as 100 U/ml. PMID:7012030

Victor, M; Weiss, J; Elsbach, P

1981-01-01

3

Oxidative DNA damage of peripheral blood polymorphonuclear leukocytes, selectively induced by chronic arsenic exposure, is associated with extent of arsenic-related skin lesions  

SciTech Connect

There is increasing evidence that oxidative stress is an important risk factor for arsenic-related diseases. Peripheral blood leukocytes constitute an important defense against microorganisms or pathogens, while the research on the impact of chronic arsenic exposure on peripheral blood leukocytes is much more limited, especially at low level arsenic exposure. The purpose of the present study was to explore whether chronic arsenic exposure affects oxidative stress of peripheral blood leukocytes and possible linkages between oxidative stress and arsenic-induced skin lesions. 75 male inhabitants recruited from an As-endemic region of China were investigated in the present study. The classification of arsenicosis was based on the degree of skin lesions. Arsenic levels were measured in drinking water and urine by Atomic Fluorescence Spectroscopy. Urinary 8-hydroxy-2?-deoxyguanosine (8-OHdG) was tested by Enzyme-Linked Immunosorbent Assay. 8-OHdG of peripheral blood leukocytes was evaluated using immunocytochemical staining. 8-OHdG-positive reactions were only present in polymorphonuclear leukocytes (PMNs), but not in monocytes (MNs). The 8-OHdG staining of PMN cytoplasm was observed in all investigated populations, while the 8-OHdG staining of PMN nuclei was frequently found along with the elevated amounts of cell debris in individuals with skin lesion. Urinary arsenic levels were increased in the severe skin lesion group compared with the normal group. No relationship was observed between drinking water arsenic or urine 8-OHdG and the degree of skin lesions. These findings indicated that the target and persistent oxidative stress in peripheral blood PMNs may be employed as a sensitive biomarker directly to assess adverse health effects caused by chronic exposure to lower levels of arsenic. -- Highlights: ? Male inhabitants were investigated from an As-endemic region of China. ? 8-OHdG-positive reactions were only present in polymorphonuclear leukocytes (PMNs). ? 8-OHdG staining of PMN nuclei was paralleled by increased debris of cells. ? Oxidative DNA damage of PMNs is associated with arsenic-related skin lesions.

Pei, Qiuling, E-mail: 924969007@qq.com [Department of Toxicology, Public Health College, Shanxi Medical University, No 56 Xin Jian Nan Lu, Taiyuan (030001) (China)] [Department of Toxicology, Public Health College, Shanxi Medical University, No 56 Xin Jian Nan Lu, Taiyuan (030001) (China); Ma, Ning [Faculty of Health Science, Suzuka University of Medical Science, Suzuka, 510-0293 (Japan)] [Faculty of Health Science, Suzuka University of Medical Science, Suzuka, 510-0293 (Japan); Zhang, Jing; Xu, Wenchao; Li, Yong; Ma, Zhifeng; Li, Yunyun; Tian, Fengjie; Zhang, Wenping [Department of Toxicology, Public Health College, Shanxi Medical University, No 56 Xin Jian Nan Lu, Taiyuan (030001) (China)] [Department of Toxicology, Public Health College, Shanxi Medical University, No 56 Xin Jian Nan Lu, Taiyuan (030001) (China); Mu, Jinjun [The Second Hospital, Shanxi Medical University, Taiyuan (030001) (China)] [The Second Hospital, Shanxi Medical University, Taiyuan (030001) (China); Li, Yuanfei [The First Hospital, Shanxi Medical University, Taiyuan (030001) (China)] [The First Hospital, Shanxi Medical University, Taiyuan (030001) (China); Wang, Dongxing; Liu, Haifang; Yang, Mimi; Ma, Caifeng; Yun, Fen [Department of Toxicology, Public Health College, Shanxi Medical University, No 56 Xin Jian Nan Lu, Taiyuan (030001) (China)] [Department of Toxicology, Public Health College, Shanxi Medical University, No 56 Xin Jian Nan Lu, Taiyuan (030001) (China)

2013-01-01

4

Polymorphonuclear leukocytes in the endometrium during the normal menstrual cycle.  

PubMed

We investigated the presence of polymorphonuclear leukocytes (PMNs) in normal endometrium. Hematoxylin and eosin stained slides of 100 endometrial curettage and biopsy specimens were reviewed for dating and presence of PMNs. Polymorphonuclear leukocytes were quantitated by chloroacetate esterase (CAE) stains. Polymorphonuclear leukocytes were present in large numbers in areas of tissue degradation (day 28 and menstrual phase endometrium) and were found only in small numbers in intact tissue throughout the cycle. The CAE and H&E stains showed minimal difference in ability to detect PMNs. Polymorphonuclear leukocytes could be easily discriminated from endometrial granulocytes, which did not stain with CAE. PMID:2448257

Poropatich, C; Rojas, M; Silverberg, S G

1987-01-01

5

Influence of light sources on the migration of polymorphonuclear leukocytes  

Microsoft Academic Search

In the process of inflammation, leukocytes must travel from the intraluminal space of the capillary to the interstitial space in order to reach the site of the inflammation. The two major populations of mature human leukocytes based on the morphology are the polymorphonuclear leukocytes (PMN), and mononuclear leukocytes (MNL). Previous research on PMNs and MNLs at the Biomedical Engineering and

Michael A. Dellavecchia; Richard B. Beard; Xiaoyan Dai

1995-01-01

6

Polymorphonuclear leukocyte and monocyte chemoattractants produced by human fibroblasts.  

PubMed Central

The elaboration of leukocyte chemotactic factors by human fibroblasts was studied. 12 lines of normal fibroblasts obtained by skin biopsy and then cultured in vitro produced chemoattractants (assessed by modified Boyden-chamber techniques) for both peripheral blood polymorphonuclear leukocytes and monocytes (obtained by Hypaque-Ficoll and dextran sedimentation). Chemotactic activity was not present performed in fibroblasts, and cycloheximide blocked its elaboration. The chemotactic activity of crude-culture supernate was heat stable (56 degrees C for 30 min), trypsin- and pronase-sensitive, and neuraminidase resistant. Characterization of the chemotactic activity by gel filtration (Sephadex G-75) showed two active fractions, one with mol wt greater than 100,000 and the other less than 10,000. In studies designed to relate these chemotactic factors to collagen, we have confirmed that type I collagen and alpha 1-chain; are chemotactically active for monocytes but not polymorphonuclear leukocytes. However, the chemotactic activity in fibroblast-culture media was media was distinct from collagen in that it attracted neutrophils, it was not precipitated by 25% ammonium sulfate, and it was resistant to collagenase treatment; ascorbic acid, in concentrations known to stimulate fibroblast collagen synthesis, had no effect on the elaboration of the chemotactic factors. Furthermore, amino acid analysis of Sephadex G-75 fractions with chemotactic activity failed to reveal amino acids such as hydroxyproline characteristic of collagen. In addition to the chemotactic factors secreted by fibroblasts, a heat-resistant factor (30 min at 56 degrees C) which generated the chemotactically active fragment of C5 (C5a) from human serum was also secreted. The elaboration of mediators of the inflammatory and immune responses by fibroblasts may initiate and(or) modulate local skin inflammatory reactions and play a protective role in vivo. PMID:438325

Sobel, J D; Gallin, J I

1979-01-01

7

Metabolic, Membrane, and Functional Responses of Human Polymorphonuclear Leukocytes to Platelet-Activating Factor  

Microsoft Academic Search

The phospholipid mediator of anaphylaxis. platelet-activat- ing factor (PAF) is chemotactic for polymorphonuclear leukocytes (PMN). We have examined this agents effects on several other PMN functions. Human PMN were pre- pared from heparinized venous blood by Ficoll gradient. Metabolic burst was examined by measurement of #{176}2use and 0 2 production in the presence or absence of PAF (10-109M). Unless cells

Leah M. Ingraham; Thomas D. Coates; John M. Allen; Coleen P. Higgins; Robert L. Baehner; Laurence A. Boxer

1982-01-01

8

Effect of antipyretics on polymorphonuclear leukocyte functions in children.  

PubMed

The aim of this study was to investigate whether fever and antipyretic drugs had an adverse effect on human polymorphonuclear leukocyte (PMN) functions (phagocytic and intracellular killing activity). Twenty febrile children with an axillary temperature of 39-40 degrees C and 20 healthy children without fever were included. Polymorphonuclear leukocytes were isolated. The effects of in vitro addition of antipyretic drugs (acetaminophen, metamizole sodium, nimesulid and ibuprofen) on PMN functions were tested. Phagocytic activity was assayed by the ingestion of yeast cells by PMNs and intracellular killing activity by the ingestion of yeast cells (stained blue) killed by PMNs. PMNs derived from febrile children exhibited better phagocytic activity when ibuprofen was added. In contrast, phagocytic activity was enhanced when acetaminophen, metamizole sodium or nimesulid was added in children without fever. Intracellular killing activity was enhanced when ibuprofen or metamizole sodium was added in children without fever. We conclude the antipyretic drugs at safely achievable concentrations do not suppress PMN function in vitro. PMID:12433060

Gürer, Umran Soyo?ul; Palanduz, Ay?e; Gürbüz, Burçak; Yildirmak, Yildiz; Cevikba?, Adile; Kayaalp, Nimet

2002-10-01

9

Functional analysis of the marginating pool of human polymorphonuclear leukocytes.  

PubMed

The intravascular pool of human polymorphonuclear leukocytes (PMN) is composed of one compartment which is circulating and another that is marginated to the vascular endothelium. Administration of B-adrenergic agonists leads to a rapid demargination with an increase in the circulating PMN pool. The marginating PMN has previously been stated to represent an older PMN based on a higher cytochemical alkaline phosphatase activity. With the understanding that circulating PMN are heterogeneous with respect to function and size we undertook the present study to evaluate the contribution of the marginating PMN to functional and volume-dependent heterogeneity. We found that PMN isolated 7 min after epinephrine administration, presumably enriched by marginating PMN, were not different in volume, biochemically measured alkaline phosphatase activity, stimulated superoxide anion release, degranulation, or phagocytosis. These data suggest that the circulating and marginating pools of PMN are interchangeable and that the marginating PMN are not enriched by a particular subpopulation of PMN. PMID:3026170

Berkow, R L; Dodson, R W

1987-01-01

10

Bactericidal activity of fractionated granule contents from human polymorphonuclear leukocytes.  

PubMed

Proteins from human polymorphonuclear leukocyte granules were extracted with 0.2 M acetate, pH 4.0, and fractionated by Sephadex G-100 column chromatography. The fractions demonstrated selective bactericidal action against a deep rough cell wall mutant of Escherichia coli O111:B4 with rough lipopolysacharide and cell wall mutants of Salmonella typhimurium LT-2 with lipoplysacharide of Ra, Rc, Rd1, Rd2, and Re types. Smooth parent strains were most resistant to the bactericidal action. Fractions with greatest activity for the mutants were from valley regions (regions of low protein concentration) between three high protein peaks comprising myeloperoxidase, protease, and lysozyme, respectively. Susceptibility of the mutants to bactericidal action increased as sugar residues decreased in lipopolysaccharide. Gram-positive bacteria were susceptible to different fractions than were the gram-negative bacteria. PMID:378830

Modrzakowski, M C; Cooney, M H; Martin, L E; Spitznagel, J K

1979-03-01

11

Especially polymorphonuclear leukocytes, but also monomorphonuclear leukocytes, roll spontaneously in venules of intact rat skin: involvement of E-selectin.  

PubMed

White blood cells roll spontaneously in venules of intact, noninflamed rat skin. We investigated noninvasively in two experimental series which leukocyte subtypes participate in this phenomenon and the possible involvement of E-selectin. Male Lewis rats were anesthetized with sodium pentobarbital, and intravital video microscopy was performed on postcapillary venules in the nail-fold of a hind leg. In series 1 acridine yellow was infused for 15 min (50 mg per kg intravenously) to stain the leukocyte nuclei in situ. With the use of fluorescence microscopy rolling leukocytes could be classified unequivocally as polymorphonuclear (granulocytes) or monomorphonuclear (lymphocytes/monocytes) by the shape of their nucleus. Irrespective of vessel depth beneath the skin surface (25-45 microm), most identified rolling leukocytes were classified as granulocytes (72%-100%; median 89%). This percentage was independent of total rolling leukocyte flux, systemic leukocyte count, or their in vitro differentiation pattern. In series 2, rats were treated with either a synthetic, highly selective E-selectin blocking peptide or a control peptide (intravenously, 12 mg peptide per kg bolus, followed by 50 mg per kg per h). E-selectin blockade significantly reduced the leukocyte rolling level to about 50% of baseline (p <0.01), whereas the rolling velocity increased (p <0.01); the control peptide had no effect. In summary, most of the leukocytes rolling spontaneously in postcapillary venules of intact rat skin are granulocytes, despite the absence of an acute inflammatory reaction. One of the adhesion molecules involved in this phenomenon is E-selectin. PMID:11841551

oude Egbrink, Mirjam G A; Janssen, Gijsbertus H G W; Ookawa, Keiko; Slaaf, Dick W; Reneman, Robert S; Wehrens, Xander H T; Maaijwee, Kristel J M; Ohshima, Norio; Struijker Boudier, Harry A J; Tangelder, Geert Jan

2002-02-01

12

Integrin stimulation regulates polymorphonuclear leukocytes inflammatory cytokine expression.  

PubMed Central

OBJECTIVE: The purpose of these studies is to investigate the role of integrin binding on the regulation of polymorphonuclear leukocyte (PMN) cytokine receptor expression. SUMMARY BACKGROUND DATA: Current knowledge in this area revolves around the ability of beta 2 integrins to mediate PMN adherence and chemotaxis. The role of alpha 1-6/beta 1 integrins in regulating cytokine receptor expression has not been probed. METHODS: Purified human PMN were adhered on plastic, fibronectin, or laminin-coated surfaces followed by the addition of iodine 125 (125I) monoclonal antibodies (mAbs) directed against tumor necrosis factor-alpha R (TNF-alpha R) p60, p80, or interleukin-1 beta R (IL-1 beta R) types I, II. Receptor expression was calculated based on the counts per minute (cpm) bound. The role of individual beta 1 integrins was assessed using mAbs directed against the alpha 1-6 subunit of the beta 1 complex, and integrin cross-linkage was achieved using secondary goat antimouse F(ab')2 antibodies. Polymorphonuclear leukocytes were pretreated with herbimycin A to determine the role of protein tyrosine kinase in mediating the effect of the beta 1 integrins. RESULTS: Adherence of PMN to Ln decreased IL-1 beta types I, II receptor expression, whereas adherence to Fn increased TNF-alpha R p60 and p80 expression. Anti-VLA-5 (CD49e) but not anti-VLA-1 through VLA-4 and VLA-6, blocked the effect of Fn on TNF-alpha receptors, whereas anti-VLA-6 but not anti-VLA-1 through VLA-5 blocked the effect of Ln on IL-1 beta receptors. Modulation of IL-1 beta and TNF-alpha receptors by VLA-5 and VLA-6 required protein tyrosine kinase activation as herbimycin A (10 micrograms/mL) blocked the affect of Fn and Ln. Changes in PMN cytokine receptor expression led to parallel changes in functional activity as assessed by the binding of 125I IL-1 beta and TNF-alpha. CONCLUSIONS: Integrin stimulation regulates the cell surface expression of PMN cytokine receptors. Ligation of CD49e upregulates TNF-alpha receptor expression, whereas binding of CD49f downregulates IL-1 beta receptor expression. Both processes are protein tyrosine kinase dependent. Changes in PMN cytokine receptor expression led to corresponding changes in functional activity. These results provide the first demonstration that chemotaxis of PMN into the interstitium provides a mechanism for ongoing participation in the local inflammatory response and is regulated by matrix protein integrin receptors. PMID:9230816

Simms, H H; D'Amico, R; Bland, K I

1997-01-01

13

Uptake of antibiotics by human polymorphonuclear leukocyte cytoplasts  

SciTech Connect

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.

Hand, W.L.; King-Thompson, N.L. (Veterans Administration Medical Center (Atlanta), Decatur, GA (USA))

1990-06-01

14

Characterization of factor H binding to human polymorphonuclear leukocytes.  

PubMed

Previous studies indicate that factor H (fH) binds to a number of cell types and may have functions other than C regulation. We have examined for fH binding to PMN using flow cytometry and radiolabeled binding assays. Binding of fH was demonstrated to be specific and saturable with approximately 6 x 10(4) binding sites/polymorphonuclear leukocytes (PMN) and a Ka value of 3.3 x 10(8) L/M. Binding of fH to PMN was ionic strength dependent, required divalent cations, and was enhanced by PMN stimulation with FMLP and calcium ionophore, A23187. The 38-kDa N-terminal tryptic fragment of fH bound to PMN and blocking experiments with mAb suggested a receptor binding site was located within the fifth SCR of fH. fH binding was not due to associations with surface-bound C3 or to CR3. Binding of fH to U937 and Raji cells, but not to T cells was also demonstrated. These studies provide presumptive evidence for a fHR on PMN. Binding of fH by fHR could enhance recognition of opsonized targets, trigger secondary intracellular events or contribute to intrinsic protection of cells against C. PMID:8228245

Avery, V M; Gordon, D L

1993-11-15

15

Neisseria gonorrhoeae suppresses the oxidative burst of human polymorphonuclear leukocytes  

PubMed Central

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

Criss, Alison K.; Seifert, H. Steven

2008-01-01

16

Interaction between Chlamydia spp. and human polymorphonuclear leukocytes in vitro.  

PubMed Central

Chlamydia psittaci and Chlamydia trachomatis elementary bodies (EB) incubated in the presence of complement or specific antibody or both caused chemotaxis of human polymorphonuclear leukocytes (PMN) in vitro. Reticulate bodies and culture supernatants had no effect on these cells. The ability of chlamydiae to enter and survive in PMN under nonopsonizing conditions was investigated by measuring the association of 3H-labeled EB and of inclusion-forming units with these phagocytes. Both assays indicated that C. psittaci as well as C. trachomatis EB are efficiently internalized. The mechanism by which this is accomplished is distinct from classical phagocytosis in that it is not dependent upon the presence of complement or antibody. Furthermore, uptake of at least C. psittaci appeared to be rapid, with no additional increase occurring after 15 min. The majority of cell-associated chlamydiae were rendered acid soluble or noninfectious within 1 h. Subsequently, there was a small but steady loss of infectivity for up to 10 h, which may have been due to the conversion of EB to the noninfectious reticulate-body form of the organism. However, even at 10 h after entry a small percentage of bacteria was still capable of infecting a second target cell. This is noteworthy in that PMN are relatively short-lived cells, and after lysis, intracellular organisms may be free to infect adjacent tissue. Electron microscopic observations were consistent with the data on uptake and persistence. The ability of a small percentage of infecting chlamydiae to maintain infectivity in PMN for at least several hours may enable these organisms subsequently to establish productive infection in permissive host cells. Images PMID:3710578

Register, K B; Morgan, P A; Wyrick, P B

1986-01-01

17

Interleukin 1 acts on cultured human vascular endothelium to increase the adhesion of polymorphonuclear leukocytes, monocytes, and related leukocyte cell lines.  

PubMed Central

Increased leukocyte adhesion to the endothelial lining of blood vessels is an essential event in inflammation and the pathogenesis of certain vascular diseases. We have studied the effect of interleukin 1 (IL-1), an inflammatory/immune mediator, on endothelial-leukocyte adhesion using quantitative in vitro assays. Selective pretreatment of cultured human umbilical vein endothelial monolayers with IL-1 (5 U/ml, 4 h) resulted in an 18.3 +/- 2.6-fold increase in human peripheral blood polymorphonuclear leukocyte (PMN) adhesion (mean +/- SEM, n = 16) and a 2.6 +/- 0.3-fold increase in monocyte adhesion (n = 7) over basal levels. IL-1-treated endothelial monolayers also supported increased adhesion of the promyelocytic cell line HL-60 and the monocytelike cell line U937 (33.0 +/- 6.0-fold, n = 6 and 4.9 +/- 0.5-fold, n = 15, respectively). In contrast, selective IL-1 pretreatment of leukocytes, or the addition of IL-1 during the adhesion assay, did not alter endothelial-leukocyte adhesion. Conditioned medium from IL-1-treated endothelial cultures also did not promote leukocyte adhesion to untreated monolayers. IL-1 induction of endothelial adhesivity was concentration dependent (maximum, 10 U/ml), time dependent (peak, 4-6 h), and reversible, was blocked by cycloheximide (10 micrograms/ml) or actinomycin D (5 micrograms/ml) but not by acetylsalicylic acid (100 microM), and occurred without detectable endothelial cell damage. IL-1 treatment of SV40-transformed human endothelial cells and dermal fibroblasts did not increase their adhesivity for leukocytes. These data suggest that IL-1 can act selectively on human vascular endothelium to increase its adhesivity for circulating blood leukocytes, and thus to localize leukocyte-vessel wall interactions at sites of inflammation in vivo. Images PMID:3877078

Bevilacqua, M P; Pober, J S; Wheeler, M E; Cotran, R S; Gimbrone, M A

1985-01-01

18

Increased hydroxyl radical generation by normal polymorphonuclear leukocytes incubated in sera from patients with leukocytoclastic vasculitis  

Microsoft Academic Search

The effect of sera from patients with untreated leukocytoclastic vasculitis was investigated on the generation of oxygen intermediates by normal polymorphonuclear leukocytes. Sera from untreated patients induced increased hydroxyl radical generation, which is one of the most potent oxidants capable of causing tissue damage. It is suggested that vascular injury may be mediated in part by enhanced production of hydroxyl

Yoshiki Miyachi; Keiko Yanase; Sadao Imamura; Yukie Niwa

1982-01-01

19

Effect of staphylococcal iron content on the killing of Staphylococcus aureus by polymorphonuclear leukocytes.  

PubMed Central

Preincubation of Staphylococcus aureus 502A in broth with increasing concentrations of ferrous sulfate progressively increased their iron content, markedly increased their susceptibility to killing by hydrogen peroxide, and did not alter their susceptibility to killing by polymorphonuclear leukocytes. PMID:7216492

Repine, J E; Fox, R B; Berger, E M; Harada, R N

1981-01-01

20

Regulation of Polymorphonuclear Leukocyte-Intestinal Epithelial Cell Interactions: Signalling Events and Potential Drug Targets  

Microsoft Academic Search

A crucial event in the inflammatory response is recruitment of polymorphonuclear leukocytes (PMNL) to a site of infection or injury. PMNL-epithelial interactions involve many fundamental cell processes, including adhesion, migra- tion, secretion, phagocytosis and apoptosis. Thus, migration of PMNL across epithelial-lined organs is a primary event component of host defense. Moreover, PMNL transepithelial migration often results in disease symptoms. New

Paul Hofman

2007-01-01

21

Cigarette Smoking Causes Sequestration of Polymorphonuclear Leukocytes Released from the Bone Marrow in Lung Microvessels  

Microsoft Academic Search

Studies from our laboratory have shown that chronic cigarette smoke exposure causes a neutrophilia asso- ciated with a shortening of the mean transit time of polymorphonuclear leukocytes (PMN) though the post- mitotic pool of the marrow. The present study was designed to test the hypothesis that PMN newly re- leased from bone marrow by smoke exposure preferentially sequestered in pulmonary

Takeshi Terashima; Maria E. Klut; Dean English; Jennifer Hards; James C. Hogg; Stephan F. van Eeden

22

Oxidative Metabolism of Polymorphonuclear Leukocytes and Serum Opsonic Activity in Chronic Renal Failure  

Microsoft Academic Search

Luminol-amplified chemiluminescence was used to study the oxidative metabolism of polymorphonuclear leukocytes (PMN), in resting state and in response to opsonized zymosan, in 65 patients with different degrees of chronic renal failure (CRF) or on regular dialysis treatment (RDT). Every patient was compared on the same day with a normal subject. Furthermore, the serum opsonic activity was evaluated, cross-matching zymosan

Leonardo Lucchi; Gianni Cappelli; Maria Angela Acerbi; Andrea Spattini; Egidio Lusvarghi

1989-01-01

23

Exudate polymorphonuclear leukocytes isolated from skin chambers are primed for enhanced response to subsequent stimulation with chemoattractant f-Met-Leu-Phe and C3-opsonized yeast particles  

Microsoft Academic Search

The ability to respond metabolically to stimulation with both soluble and paniculate substances was investigated in human polymorphonuclear leukocytes (PMNLs) isolated from an aseptic inflammatory reaction. Exudate PMNLs isolated from skin chambers (E-PMNLs) and blood PMNLs isolated from the peripheral blood (B-PMNLs) of the same individual were investigated in parallel. E-PMNLs were primed, resulting in an increased chemiluminescence (CL) response

Gunnar Briheim; Brittinger Coble; Olle Stendahl; Claes Dahlgren

1988-01-01

24

Selectivity of the 2-deoxyglucose transport system in human and guinea pig polymorphonuclear leukocytes.  

PubMed Central

To determine whether the deleterious action of D-galactose upon phagocyte function could be related to inhibition of glucose uptake, the properties of glucose transport were investigated by following the incorporation of [G-3H]2-deoxyglucose into human and guinea pig polymorphonuclear leukocytes (PMN). Uptake of [G-3H]2-deoxyglucose by guinea pig PMN proceeded in vitro with a Km of 1.8 mM and Vmax of 0.67 nmol/min per 10(6) cells. This system was competitively inhibited by glucose and mannose but was not significantly affected by galactose, fructose, or 3-0-methylglucose. Maximal uptake of 2-deoxyglucose occurred at 41 degrees C, and phosphorylation was necessary for its intracellular concentration. Transport of 2-deoxyglucose, although not altered by uncouplers of oxidative phosphorylation, was sensitive to inhibitors of glycolysis. Preincubation of cells with 2 mM iodoacetate for 30 min significantly reduced the uptake of 2-deoxyglucose and the intracellular levels of adenosine-5'-triphosphate without decreasing cell viability. These results indicated that uptake of 2-deoxyglucose in guinea pig PMN occurred by facilitated diffusion with subsequent phosphorylation. Similar results were obtained with PMN isolated from human peripheral blood. PMID:873606

Litchfield, W J; Wells, W W

1977-01-01

25

Oxidation of proteins in rat heart and lungs by polymorphonuclear leukocyte oxidants  

Microsoft Academic Search

The ability of the polymorphonuclear leukocyte (PMN) oxidants, hypochlorous acid (HOC1) and hydrogen peroxide (H2O2), to oxidize proteins in rat heart and lung tissues was investigated. Cardiac myocytes, heart tissue slices, isolated perfused hearts, and lung tissue slices, were treated with HOCI and H2O2 and the extent of methionine and cysteine oxidation was determined in the cellular proteins. Cardiac tissues

Henry Fliss

1988-01-01

26

Alkali-Degraded Cornea Generates a Low Molecular Weight Chemoattractant for Polymorphonuclear Leukocytes  

Microsoft Academic Search

Purpose. The current study was designed to determine if a polymorphonuclear leukocyte (PMN) chemoattractant is derived from alkali-degraded whole cornea and to establish a range for its molecular weight. Methods. We utilized a collagen gel-visual chemotactic assay to quantify the directional move- ment of PMN exposed to alkali-degraded corneas (30 min or 24 hi). In this experiment, the sample to

Roswell R. Pfister; Jeffrey L. Haddox; Charnell I. Sommers

27

Polymorphonuclear leukocytes enhance release of growth factors by cultured endothelial cells.  

PubMed

Porcine aortic endothelial cells (PAECs) in culture constitutively secrete polypeptide (endothelium-derived) growth factors (EDGFs) into the surrounding medium. Incubation of PAECs with human peripheral blood polymorphonuclear leukocytes (PMNs) caused a significant increase in EDGF release as assessed by [3H]thymidine incorporation into BALB/c 3T3 mouse fibroblasts and cell proliferation assay. The effect was time dependent and correlated with the number of PMNs, reaching a maximum with a 1:1 PAEC to PMN ratio. Generation of mitogenic activity was prevented by cycloheximide, indicating a requirement for de novo protein synthesis. Antibody-mediated inhibition assays suggested that mitogenic activity was due to platelet-derived growth factor and basic fibroblast growth factor. When supernatant from N-formyl-methionyl-leucyl-phenylalanine-stimulated PMNs was substituted for PMNs during incubation with PAECs, powerful mitogenic activity was generated, indicating the involvement of soluble mediators. A role for free oxygen radicals was ruled out by experiments in which superoxide dismutase and catalase did not prevent the increase in mitogenic activity. By contrast, serine protease inhibitors such as soybean trypsin inhibitor, alpha 1-antitrypsin, and eglin C reduced the PMN-stimulating activity by 70%, 80%, and 100%, respectively. The possible involvement of cathepsin G and elastase was investigated. Cathepsin G and elastase, when substituted for PMNs, increased the release of EDGFs in a dose-dependent fashion, mimicking the effect of PMNs. These findings suggest a new role for leukocyte-vessel wall interactions in the proliferative feature of atherosclerosis. PMID:8274467

Totani, L; Piccoli, A; Pellegrini, G; Di Santo, A; Lorenzet, R

1994-01-01

28

An evaluation of the role of leukocytes in the pathogenesis of experimentally induced corneal vascularization. III. Studies related to the vasoproliferative capability of polymorphonuclear leukocytes and lymphocytes.  

PubMed Central

Studies in the past have suggested that leukocytes are a prerequisite to corneal vascularization. To test this hypothesis further, experiments were conducted to determine whether the intracorneal instillation of polymorphonuclear leukocytes, lymphocytes, or components of leukocytes would induce a corneal vascular ingrowth. These cells or cellular fractions were injected intracorneally into Fisher albino rats whose circulating leukocytes had been depleted by total body x-irradiation. Polymorphonuclear leukocytes isolated from glycogen-induced peritoneal exudates caused a corneal vascular invasion, but lymphocytes obtained from thymus, spleen, and lymph nodes failed to do so. To learn whether an extractable factor could be isolated from polymorphonuclear leukocytes these cells were suspended in isotonic saline, ultrasonified and then centrifuged at 101,952g for 1 hour. Aliquots of the resulting sediment and supernatant were injected intracorneally into rats with radiation-induced leukopenia. The nonsedimentable supernatant caused corneal vascularization, but the sediment did not provoke the phenomenon. These studies not only provide further support for the hypothesis that leukocytes initiate corneal vascularization, possibly by the release of one or more heat labile chemical mediators, but directly implicate the polymorphonuclear leukocyte in this process. Images Figures 1-3 Figure 4 Figure 5 Figure 6 PMID:1247083

Fromer, C. H.; Klintworth, G. K.

1976-01-01

29

Killing of Proteus mirabilis by polymorphonuclear leukocyte granule proteins: evidence for species specificity by antimicrobial proteins.  

PubMed

Low-molecular-weight (Mr, ca. 3,800) polypeptides containing human defensins HNP-1 and HNP-2 (T. Ganz, M. S. Selsted, D. Szlarek, S. L. Harwig, K. Daher, D. F. Bainton, and R. I. Lehrer, J. Clin. Invest. 76:1427-1434, 1985) prepared in our laboratory from acid extracts of human polymorphonuclear granulocyte granules and purified human defensins were found to exert potent bactericidal action against Proteus mirabilis. The antimicrobial action of the extracts of human polymorphonuclear leukocytes granules against P. mirabilis appears to be due to the presence of the defensins. Because P. mirabilis resists the antimicrobial action of other granule proteins, we interpret the present results to mean that the various antimicrobial proteins display species specificity in their microbicidal action. PMID:3275586

Shafer, W M; Engle, S A; Martin, L E; Spitznagel, J K

1988-01-01

30

Bovine polymorphonuclear leukocytes increase sensitivity to noradrenaline in isolated mesenteric arteries.  

PubMed Central

1. The effects of polymorphonuclear leukocytes (PMN) on vascular function to (-)-noradrenaline were examined in vitro. Purified bovine PMN were incubated in siliconized organ baths containing rings of bovine mesenteric arteries, after which a concentration-effect curve in response to (-)-noradrenaline was obtained. 2. PMN-derived products induced a long lasting concentration-dependent contraction of the blood vessels generating 24.4 +/- 6.8% of the maximal tension to (-)-noradrenaline at a cell concentration of 2.5 x 10(6) ml-1. The contractile response was also found in endothelium-denuded vascular rings. 3. PMN present in the organ bath caused an increase in the sensitivity of vascular rings to (-)-noradrenaline. At a cell number of 2.5 x 10(6) PMN ml-1 the pD2-value for (-)-noradrenaline was augmented 0.40 +/- 0.05 (P less than 0.001), while total contraction at the highest concentration (-)-noradrenaline was not affected. This increase in sensitivity was dependent on an intact endothelium. 4. The increase in sensitivity to (-)-noradrenaline by PMN was inhibited by superoxide dismutase, but not by catalase, dimethylthiourea, indomethacin or nordihydroguaiaretic acid. The non-stimulated bovine PMN produced oxygen radicals as measured by chemiluminescence. 5. Simultaneous incubation of PMN and (-)-noradrenaline with arterial rings induced an increase in the release of prostacyclin, measured by an elevated concentration of 6-keto-prostaglandin F1 alpha in the supernatant. 6. It is concluded that PMN can increase vascular tone directly or indirectly probably via the interaction of PMN-derived superoxide anions with endothelium-derived relaxing factor. PMID:1628145

De Kimpe, S. J.; Van Heuven-Nolsen, D.; Nijkamp, F. P.

1992-01-01

31

Production of reactive oxygen species by man-made vitreous fibres in human polymorphonuclear leukocytes.  

PubMed

Human polymorphonuclear leukocytes (PMNL) or erythrocytes, isolated from human blood, were exposed to graded doses of asbestos (chrysotile), quartz, or man-made vitreous fibres (MMVF), i.e. refractory ceramic fibres (RCF), glasswool, or rockwool fibres. None of the MMVF affected either the viability of PMNL, as measured by trypan blue exclusion test, or induced haemolysis, whereas the positive controls, quartz and chrysotile, dose-dependently induced haemolysis in PMNL. MMVF did not increase the release of lactate dehydrogenase (LDH) from the PMNL, whereas the positive controls, chrysotile and quartz, induced a marked and dose-dependent release of LDH. When PMNL were exposed to MMVF, some of the fibre types slightly increased the levels of free intracellular calcium ([Ca2+]i) within the cells in a manner similar to that induced by chrysotile or quartz. All MMVF induced a dose-dependent production of reactive oxygen species (ROS) in PMNL, with RCF-induced production of ROS being the most marked. Production of ROS by MMVF seemed to depend on the availability of extracellular calcium because it could be attenuated with a Ca2+ channel blocker, verapamil, or a Ca2+ chelating agent, EGTA. Production of ROS may be a common pathway through which PMNL respond to MMVF-induced cell activation, but alterations of levels of free intracellular Ca2+ do not seem to be an absolute prerequisite for this effect. Fibre length seemed not to be an important factor in affecting the ability of MMVF to induce ROS production in PMNL. However, the balance between different elements in the fibre seemed importantly to affect the biological activity of a fibre. PMID:10413242

Ruotsalainen, M; Hirvonen, M R; Luoto, K; Savolainen, K M

1999-06-01

32

Activation of Polymorphonuclear Leukocytes by Candidate Biomaterials for an Implantable Glucose Sensor  

PubMed Central

Background Continuous monitoring of glucose by implantable microfabricated devices offers key advantages over current transcutaneous glucose sensors that limit usability due to their obtrusive nature and risk of infection. A successful sensory implant should be biocompatible and retain long-lasting function. Polymorphonuclear leukocytes (PMN) play a key role in the inflammatory system by releasing enzymes, cytokines, and reactive oxygen species, typically as a response to complement activation. The aim of this study was to perform an in vitro analysis of PMN activation as a marker for biocompatibility of materials and to evaluate the role of complement in the activation of PMN. Methods Fifteen candidate materials of an implantable glucose sensor were incubated in lepirudin-anticoagulated whole blood. The cluster of differentiation molecule 11b (CD11b) expression on PMN was analyzed with flow cytometry and the myeloperoxidase (MPO) concentration in plasma was analyzed with enzyme-linked immunosorbent assay. Complement activation was prevented by the C3 inhibitor compstatin or the C5 inhibitor eculizumab. Results Three of the biomaterials (cellulose ester, polyamide reverse osmosis membrane, and polyamide thin film membrane), all belonging to the membrane group, induced a substantial and significant increase in CD11b expression and MPO release. The changes were virtually identical for these two markers. Inhibition of complement with compstatin or eculizumab reduced the CD11b expression and MPO release dose dependently and in most cases back to baseline. The other 12 materials did not induce significant PMN activation. Conclusion Three of the 15 candidate materials triggered PMN activation in a complement-dependent manner and should therefore be avoided for implementation in implantable microsensors. PMID:22226271

Sokolov, Andrey; Hellerud, Bernt Christian; Lambris, John D; Johannessen, Erik A; Mollnes, Tom Eirik

2011-01-01

33

Aminophylline induced oxidative metabolism in isolated canine polymorphonuclear leukocytes.  

PubMed

Adenosine reportedly mediates myocardial and skeletal blood flow, bronchoconstriction, and cellular production of toxic oxygen radicals. Cellular effects of adenosine can be antagonized by the methylxanthines, which are widely used in the clinical treatment of obstructive airway diseases. Methylxanthine compounds such as aminophylline and theophylline inhibit the cyclic nucleotide phosphodiesterase of smooth muscle, reversing pathogenic states of bronchoconstriction. Recent techniques in flow cytometry allow examination of individual cells for the electrophysiological and metabolic cellular side effects of methylxanthine therapy. We report that the flow cytometric examination of isolated canine peripheral neutrophils, in the presence of therapeutic concentrations of aminophylline resulted in small but significant membrane depolarization and almost fivefold increases in baseline cytosolic H202 levels. If aminophylline is capable of direct in vitro activation of isolated canine neutrophils it may have the capacity to potentiate neutrophil activation in vivo: indirectly by competing with circulating modifiers, such as adenosine, for cell surface receptor sites and directly by the induction of toxic oxygen radicals as demonstrated here. H202 induction by aminophylline and other xanthine derivatives may become clinically important in instances of vascular occlusion, stasis, or instances of reperfusion where neutrophils may become activated. In an activated state, neutrophils could contribute to pathogenicity and tissue damage by indiscriminantly releasing oxygen-reactive species. PMID:2621314

Gruber, D F; O'Halloran, K P; Farese, A M

1989-01-01

34

Functional and metabolic studies of polymorphonuclear leukocytes in the canine homologue of congenital Pelger-Huet Anomaly  

E-print Network

FUNCTIONAL AND METABOLIC STUDIES OF POLYMORPHONUCLEAR LEUKOCYTES IN THE CANINE HOMOLOGUE OF CONGENITAL PELGER-HUET ANOMALY A Thesis by ELIZABETH JARRATT BROWDER Submitted to the Graduate College of Texas A8M University in partial fulfillment... Leukocytes in the Canine Homologue of Congenital Pelger-Huet Anomaly . (May 1985) Elizabeth Jarratt Browder, B. A. , Bay lor University; B. S. , Texas ASM University; D. V. M. , Texas A8M University Chairman of Advisory Committee: Dr. lan Tizard...

Browder, Elizabeth Jarratt

2012-06-07

35

Luminol-enhanced chemiluminescence of rabbit polymorphonuclear leukocytes: The nature of oxidants that directly cause luminol oxidation  

Microsoft Academic Search

In this study, we investigated the pathways (including the formation of hydroxyl radicals and chloramines) leading to luminol\\u000a chemiluminescence induced by hypochlorite generated in a suspension of stimulated rabbit polymorphonuclear leukocytes. Chemiluminescence\\u000a of leukocytes stimulated by phorbol myristate acetate, which was enhanced by luminol (0.02 mM), did not change in the presence\\u000a of dimethyl sulfoxide at moderate concentrations (0.02–2.6 mM),

D. I. Roshchupkin; N. S. Belakina; M. A. Murina

2006-01-01

36

Damage of cultured chondrocytes by hydrogen peroxide derived from polymorphonuclear leukocytes: a possible mechanism of cartilage degradation  

Microsoft Academic Search

To study the mechanisms of chondrocyte damage, chondrocyte cytotoxicity as shown by chromium-51 release induced by polymorphonuclear leukocytes (PMNLs) was examined. PMNLs significantly enhanced chondrocyte cytotoxicity in the presence of phorbol dibutyrate. This chondrocyte damage was abolished by the addition of catalase, whereas superoxide dismutase and scavengers of hydroxyl radicals and protease inhibitors failed to reverse it. When cartilage matrix

R. Saura; T. Matsubara; K. Hirohata; H. Itoh

1992-01-01

37

Endothelin1 Changes Polymorphonuclear Leukocytes' Deformability and CD11b Expression and Promotes Their Retention in the Lung  

Microsoft Academic Search

Endothelin (ET)1 influences polymorphonuclear leukocyte (PMN)- endothelial cell interactions. The aim of this study was to ex- amine the effect of ET-1 on factors that influence PMN-endo- thelial interaction and retention in the lung both in vitro and in vivo. In vitro , high concentration of ET-1 ( > 10 2 8 M) rapidly increased PMN F-actin content (10 2

Yukio Sato; James C. Hogg; Dean English; Stephan F. van Eeden

38

Elevated expression of polymorphonuclear leukocyte elastase in breast cancer tissue is associated with tamoxifen failure in patients with advanced disease  

Microsoft Academic Search

Besides a variety of other proteases, polymorphonuclear leukocyte elastase (PMN-E) is also suggested to play a role in the processes of tumour cell invasion and metastasis. Yet, there is only limited data available on the relation between the tumour level of PMN-E and prognosis in patients with primary breast cancer, and no published information exists on its relation with the

J A Foekens; Ch Ries; M P Look; C Gippner-Steppert; J G M Klijn; M Jochum

2003-01-01

39

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

PubMed

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 ?2 integrin family (CD11/CD18 family). Therefore, we discuss our investigations into the mechanisms by which ?2 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 ? subunits (CD11a and CD11c). Furthermore, it was found that the ? 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 ? subunits. Among these, only CD11b displayed inhibition of PMN migration on BC surfaces. © 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2014. PMID:25231265

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

2014-09-17

40

The effect of apomorphine on exocytosis and metabolic burst of polymorphonuclear leukocytes.  

PubMed Central

1 In rabbit polymorphonuclear leukocytes (PMNLs) apomorphine at 10-100 microM inhibits fMet-Leu-Phe and A23187-induced exocytosis, and the phorbol myristate acetate- and fMet-Leu-Phe-induced activation of the metabolic burst. The secretory response was not restored by washing the cells after pretreatment with apomorphine. 2 The inhibitory effect of apomorphine was not prevented by the dopamine receptor antagonists haloperidol and pimozide, nor did dopamine itself inhibit fMet-Leu-Phe-induced exocytosis. It therefore seems unlikely that effects are mediated via dopamine receptors. However, sulphydryl reagents reduced the inhibitory effect of apomorphine, suggesting that it may depend upon interaction with susceptible sulphydryl groups, the intactness of which is required for exocytosis and other functions of PMNLs. PMID:3122866

Elferink, J. G.

1987-01-01

41

Stimulatory effect of some plant extracts used in homeopathy on the phagocytosis induced chemiluminescence of polymorphonuclear leukocytes.  

PubMed

Some plant extracts on a large range of dilutions as used in Homeopathy were tested on the chemiluminescence emission produced by polymorphonuclear leukocytes. The high stimulatory action was noticed when extracts from Uvae Ursi and Saponaria were tested, as the classical effect exerted by zymosan was exceeded. A moderate stimulatory action comparable with that of zymosan was found when extracts from Echmaceea, Aleo and Prumis were used, as well as in the case of Propolis. The relationship between stimulatory effect and the concentration range is modulated as function of the extract source, several peaks being observed for some dilutions (Saponana), but generally no quantitative relations were obtained. By studying the time when a chemiluminescence peak was observed, it is possible to estimate wether the weight of the NADPH oxidase or myeloperoxidase pathways are involved in the stimulatory effect on polymorphonuclear leukocytes. PMID:11712436

Crocnan, D O; Greabu, M; Olinescu, R

2000-01-01

42

Bacterial-lipopolysaccharide-induced release of lactoferrin from human polymorphonuclear leukocytes: role of monocyte-derived tumor necrosis factor alpha.  

PubMed Central

We have examined the role played by human peripheral blood monocytes in mediating responses of human polymorphonuclear leukocytes (PMN) to bacterial lipopolysaccharide (LPS) in vitro. When incubated with Salmonella typhimurium LPS at 37 degrees C, human PMN suspended in serum-free buffer released the specific granule constituent lactoferrin into the surrounding medium. Release of lactoferrin from PMN varied with the concentration of LPS (1 to 1,000 ng/ml) as well as with the duration of incubation (2 to 60 min) and was not accompanied by significant release of the cytoplasmic enzyme lactate dehydrogenase. LPS-induced release of lactoferrin from PMN was augmented significantly when cell suspensions were supplemented with additional monocytes and lymphocytes. Only monocytes, however, secreted significant amounts of lactoferrin-releasing activity (in a time- and concentration-dependent manner) when incubated separately with LPS. Lactoferrin-releasing activity was heat (80 degrees C for 15 min) labile, eluted after chromatography on Sephadex G-100 with an apparent molecular weight of approximately 60,000, and was inhibited by antibodies to tumor necrosis factor alpha. Thus, LPS-induced noncytotoxic release of lactoferrin from human PMN suspended in serum-free buffer is mediated, at least in part, by tumor necrosis factor alpha derived from contaminating monocytes. PMID:3679539

Koivuranta-Vaara, P; Banda, D; Goldstein, I M

1987-01-01

43

The effect of low levels of dietary cobalt on the chemiluminescence response of polymorphonuclear leukocytes of goats  

Microsoft Academic Search

Twenty ten-week-old newly weaned male Batinah goats were randomly assigned to a control (n=10) and a treated (n=10) group and were fed a diet containing 0.1mg\\/kg DM cobalt (Co). Goats in the treated group received bi-monthly subcutaneous injections of 2000?g of hydroxycobalamin. The phagocytic function of the polymorphonuclear leukocytes (PMN) were tested using a luminol-dependent chemiluminescence assay with opsonized zymosan

Eugene H. Johnson; Khalid Al-Habsi; Rashid Al-Busaidy; Samera Kasim Khalaf

2010-01-01

44

Selective Labilization of Specific Granules in Polymorphonuclear Leukocytes by Phorbol Myristate Acetate  

PubMed Central

The action of phorbol myristate acetate (PMA), the active principle of croton oil, on polymorphonuclear leukocytes (PMNs) has been evaluated in this study. Small amounts of PMA caused the rapid development of vacuoles in neutrophils and the disappearance of specific granules. Histochemical and cytochemical studies revealed that alkaline phosphatase activity was transferred to vacuoles and disappeared from the cells, while myeloperoxidase activity remained associated with intact azurophilic lysosomes. Electron-dense tracers indicated that the vacuole membranes originated, at least in part, from the cell wall of the neutrophils. The results indicate that PMA stimulates events remarkably similar to those which take place when bacteria are engulfed by PMNs, except for the failure of azurophilic lysosomes to participate in PMA-induced vacuole formation. PMA appears to be the first chemical agent capable of inducing selective labilization of specific granules in the neutrophil. ImagesFigs 5 and 6Fig 1Fig 2Figs 7 and 8Fig 9Fig 10Fig 3Fig 4 PMID:4133056

White, James G.; Estensen, Richard D.

1974-01-01

45

Burkholderia pseudomallei activates complement and is ingested but not killed by polymorphonuclear leukocytes.  

PubMed

The mechanism by which Burkholderia pseudomallei is resistant to lysis by human serum is unknown but may include interference with complement activation, effective opsonization, or complement-mediated lysis. We investigated the interaction of B. pseudomallei with complement in the presence and absence of specific antibody to determine potential mechanisms of serum resistance. We demonstrated rapid activation and consumption of complement by B. pseudomallei which, in the absence of specific antibody, occurred predominantly via the alternative pathway. Complement activation was associated with deposition of the opsonically active C3b and iC3b fragments on the bacterial surface. C5b-9, detected on the bacterial surface after opsonic periods of 1 to 60 min, was susceptible to elution by 1 M NaCl, indicating that resistance to complement-mediated lysis may result from deposition of the membrane attack complex in a nonmicrobicidal location. To define the role of opsonins, we investigated the ability of polymorphonuclear leukocytes (PMNL) to phagocytose B. pseudomallei. Phagocytosis of bacteria by PMNL, and the observed oxidative response, was significantly increased by opsonization of organisms with complement and/or specific antibody. Despite opsonophagocytosis by PMNL and the production of an oxidative response, no significant bacterial killing was observed. PMID:8945532

Egan, A M; Gordon, D L

1996-12-01

46

Human polymorphonuclear leukocytes of the bone marrow, circulation, and marginated pool: function and granule protein content.  

PubMed

Polymorphonuclear leukocytes (PMN) demonstrate altered function during acute infections and after administration of corticosteroids. We questioned whether or not such changes are due to population shifts from functionally different compartments of the granulocyte pool. Volunteers were given epinephrine to induce demargination or hydrocortisone (HC) to promote egress of PMN from the bone marrow. PMN obtained before and after drug administration were compared for adherence, chemotaxis, luminol-enhanced chemiluminescence, and total content and release of lactoferrin (LF), myeloperoxidase (MPO), and beta-glucuronidase (beta-glu). Epinephrine induced a significant neutrophilia of mature PMN (segmented neutrophils), but there were no changes in function or granule protein content. HC induced a significant neutrophilia with segmented neutrophils and immature PMN (bands). Circulating PMN obtained 4 hr after HC administration demonstrated less adherence, increased chemiluminescence, increased MPO release, and decreased MPO content. Band neutrophils, however, were more adherent than segmented PMN and showed a similar decrease in adherence following HC in vivo. Thus alteration of PMN adherence following intravenous corticosteroids is not due to an influx of immature neutrophils. On the other hand, it is possible that MPO content and release and capacity for oxidative metabolism change as PMN mature. PMID:2998184

Hetherington, S V; Quie, P G

1985-11-01

47

Lactoferrin: its role as a Ga-67-binding protein in polymorphonuclear leukocytes  

SciTech Connect

Gallium-67 bound to lactoferrin - an iron-binding protein found in high concentration in polymorphonuclear leukocytes - has been isolated from PMNs that have previously been incubated with Ga-67 citrate. Although the cell-labeling efficiency was highly variable (0.026-10%), much of the activity that did bind to the PMNs (74.8 +- 10%) was recovered in the supernatant after sonication and centrifugation. About half (approx. 47%) of the PMN-bound activity was retained after dialysis and was presumably bound to macromolecules in the supernatant. When this retained activity was placed on a column containing immobilized antilactoferrin antibody, almost three quarters of the activity was bound to the column. This bound activity was (36 +- 17%) of the total activity absorbed by the PMN. The addition to the antilactoferrin column of a known antigen-antibody-dissociating agent caused the dissolution of the complex. No significant activity was bound to a control column. The findings indicate that lactoferrin is a major Ga-67-binding protein present in PMNs and suggest that it may play a major role in Ga-67 localization in an abscess. These results support the contention that molecules binding ferric iron have an important effect on Ga-67 distribution in vivo.

Weiner, R.; Hoffer, P.B.; Thakur, M.L.

1981-01-01

48

Bactericidal activity of fractionated granule contents from human polymorphonuclear leukocytes: role of bacterial membrane lipid.  

PubMed Central

Granule contents from human polymorphonuclear leukocytes were prepared by extraction with 0.2 M acetate, pH 4. A buffer extract fraction (peak D) obtained by Sephadex G-100 column chromatography demonstrated distinct antimicrobial activity toward Acinetobacte sp. independent of added H2O2 or Cl-. The protein of this fraction had an apparent molecular weight of 9,000 and demonstrated time and dose dependence that was more active against stationary-growth cells than mid-log-phase cells. The bactericidal activity of the fraction was most active at 37 degrees C, with only slight activity demonstrated at 22 degrees C and no activity at 4 degrees C. Boiling the granule fraction for 30 min did not affect the antimicrobial activity. However, pronase or trypsin pretreatment of the peak D fraction reduced its antimicrobial activity. When the membrane lipid composition of Acinetobacter sp. was altered by growth on specific n-alkane carbon sources, the susceptibility to the granule fraction was also altered. Resistance to the activity of the granule fraction increased as the carbon chain length of the growth substrate increased. Liposomes formed from Acinetobacter sp. lipid extracts and containing glucose were made leaky with the addition of the granule fraction (boiled and not boiled), suggesting a membrane-disruptive activity of the granule protein against Acinetobacter sp. membranes. PMID:7019076

Modrzakowski, M C; Paranavitana, C M

1981-01-01

49

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

PubMed

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

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

1975-04-01

50

Burkholderia pseudomallei activates complement and is ingested but not killed by polymorphonuclear leukocytes.  

PubMed Central

The mechanism by which Burkholderia pseudomallei is resistant to lysis by human serum is unknown but may include interference with complement activation, effective opsonization, or complement-mediated lysis. We investigated the interaction of B. pseudomallei with complement in the presence and absence of specific antibody to determine potential mechanisms of serum resistance. We demonstrated rapid activation and consumption of complement by B. pseudomallei which, in the absence of specific antibody, occurred predominantly via the alternative pathway. Complement activation was associated with deposition of the opsonically active C3b and iC3b fragments on the bacterial surface. C5b-9, detected on the bacterial surface after opsonic periods of 1 to 60 min, was susceptible to elution by 1 M NaCl, indicating that resistance to complement-mediated lysis may result from deposition of the membrane attack complex in a nonmicrobicidal location. To define the role of opsonins, we investigated the ability of polymorphonuclear leukocytes (PMNL) to phagocytose B. pseudomallei. Phagocytosis of bacteria by PMNL, and the observed oxidative response, was significantly increased by opsonization of organisms with complement and/or specific antibody. Despite opsonophagocytosis by PMNL and the production of an oxidative response, no significant bacterial killing was observed. PMID:8945532

Egan, A M; Gordon, D L

1996-01-01

51

Quantitation of a cationic antimicrobial granule protein of human polymorphonuclear leukocytes by ELISA.  

PubMed

The quantitation of CAP57, a highly hydrophobic, native cationic antigen of human polymorphonuclear leukocytes has been achieved using ELISA. An important feature determining the sensitivity and precision of the ELISA was the reduction of non-specific protein-protein binding, particularly in the inhibition assays, thus eliminating high backgrounds obtained with presently available methodology. Washing of the solid phase-bound antigen and blocking of the non-specific binding sites using a potassium phosphate buffer containing heparin largely contributed to this increased sensitivity. The inhibition assays were conducted using antigen concentrations over the range of 0.9-120 ng. The assay is highly specific and can be performed using monoclonal antibodies and polyclonal antibodies. Non-specific reactions were observed only when high concentrations of antigen (greater than 100 ng) were present in the inhibition mixture. The technique as described is extremely simple, highly reproducible and could be of value in the detection of cationic antimicrobial proteins in the clinical setting in the future. PMID:2913156

Pereira, H A; Martin, L E; Spitznagel, J K

1989-02-01

52

Rickettsial effects on leukotriene and prostaglandin secretion by mouse polymorphonuclear leukocytes.  

PubMed Central

Typhus rickettsiae were incubated with mouse exudative polymorphonuclear leukocytes (PMN), and supernatants were examined for leukotriene B4 (LTB4) and prostaglandin E2 (PGE2) secretion by radioimmunoassay. PMN incubated with native rickettsiae secreted significantly more LTB4 and PGE2 than did those incubated with buffer alone. Autacoid secretion was dependent on both the time of PMN incubation with rickettsiae and the number of rickettsiae present in the incubation suspension. Rickettsial stimulation of LTB4 secretion was associated with rickettsial hemolytic activity; treatments which inactivated the rickettsial hemolysin abolished the ability of rickettsiae to stimulate PMN LTB4 secretion. Trifluoperazine, which did not alter the rate of phagocytosis of rickettsiae by PMN, stimulated rickettsial effects on secretion of both LTB4 and PGE2 but inhibited the PMN LTB4 response to A23187. This suggested that the PMN response to rickettsiae and to the calcium ionophore involved differing mechanisms of activation. Finally, rabbit antirickettsial antiserum, which inhibited rickettsial hemolysis and was opsonic, did not block the effects of rickettsiae on PMN LTB4 secretion. PMID:1846125

Walker, T S; Hoover, C S

1991-01-01

53

Cytotoxic Necrotizing Factor Type 1 Production by Uropathogenic Escherichia coli Modulates Polymorphonuclear Leukocyte Function  

PubMed Central

Many strains of uropathogenic Escherichia coli (UPEC) produce cytotoxic necrotizing factor type 1 (CNF1), a toxin that constitutively activates the Rho GTPases RhoA, Rac1, and Cdc42. We previously showed that CNF1 contributes to the virulence of UPEC in a mouse model of ascending urinary tract infection and a rat model of acute prostatitis and that a striking feature of the histopathology of the mouse bladders and rat prostates infected with CNF1-positive strains is an elevation in levels of polymorphonuclear leukocytes (PMNs). We also found that CNF1 synthesis leads to prolonged survival of UPEC in association with human neutrophils. Here, we tested the hypothesis that CNF1 production by UPEC diminishes the antimicrobial capacity of mouse PMNs by affecting phagocyte function through targeting Rho family GTPases that are critical to phagocytosis and the generation of reactive oxygen species. We found that, as with human neutrophils, CNF1 synthesis provided a survival advantage to UPEC incubated with mouse PMNs. We also observed that CNF1-positive UPEC down-regulated phagocytosis, altered the distribution of the complement receptor CR3 (CD11b/CD18), enhanced the intracellular respiratory burst, and increased levels of Rac2 activation in PMNs. From these results, we conclude that modulation of PMN function by CNF1 facilitates UPEC survival during the acute inflammatory response. PMID:16113245

Davis, Jon M.; Rasmussen, Susan B.; O'Brien, Alison D.

2005-01-01

54

A monoclonal antibody that inhibits the antimicrobial action of a 57 KD cationic protein of human polymorphonuclear leukocytes.  

PubMed

Two monoclonal antibodies (mAb) specific for epitopes of a 57,000 m.w., cationic antimicrobial protein (CAP57) purified from granules of human polymorphonuclear leukocytes (PMN) have been produced. Both were IgG1 mouse antibodies with typical heavy and light chain structure. The mAb reactive with CAP57 failed to react specifically with other heretofore defined PMN or serum proteins as shown by ELISA. Both mAb showed specific reactivity in Western blots with CAP57. One of these mAb (P1G8) inhibited the antimicrobial action of CAP57 by 50% at a ratio of 62.5 micrograms antibody per microgram CAP57. The other mAb, P2A5, had no inhibitory capacity for CAP57. Binding constants of the two mAb for the antigen were determined and were found to be virtually identical. Thus, the greater inhibitory capacity of P1G8 for bacterial killing by CAP57 was not directly related to binding strength of the mAb. Competition experiments showed that unlabeled P1G8 could compete as well against radiolabeled P2A5 as could unlabeled P2A5. In the reverse experiment, it was seen that P1G8 competed with radiolabeled P1G8 for CAP57 better than unlabeled P2A5. These findings could be due to two antibodies that recognize different but adjacent epitopes on CAP57, one of the epitopes (P1G8) being closer to structure(s) of the protein essential to its antimicrobial action. Immunocytochemical studies showed positive staining with both mAb. The reaction was restricted to the cytoplasm of peripheral blood PMN and was of a granular pattern. Other peripheral blood cells (which included red blood cells, eosinophils, monocytes, and lymphocytes) failed to bind either mAb. PMID:3302042

Spitznagel, J K; Pereira, H A; Martin, L E; Guzman, G S; Shafer, W M

1987-08-15

55

Caffeic Acid Phenethyl Ester and Its Amide Analogue Are Potent Inhibitors of Leukotriene Biosynthesis in Human Polymorphonuclear Leukocytes  

PubMed Central

Background 5-lipoxygenase (5-LO) catalyses the transformation of arachidonic acid (AA) into leukotrienes (LTs), which are important lipid mediators of inflammation. LTs have been directly implicated in inflammatory diseases like asthma, atherosclerosis and rheumatoid arthritis; therefore inhibition of LT biosynthesis is a strategy for the treatment of these chronic diseases. Methodology/Principal Findings Analogues of caffeic acid, including the naturally-occurring caffeic acid phenethyl ester (CAPE), were synthesized and evaluated for their capacity to inhibit 5-LO and LTs biosynthesis in human polymorphonuclear leukocytes (PMNL) and whole blood. Anti-free radical and anti-oxidant activities of the compounds were also measured. Caffeic acid did not inhibit 5-LO activity or LT biosynthesis at concentrations up to 10 µM. CAPE inhibited 5-LO activity (IC50 0.13 µM, 95% CI 0.08–0.23 µM) more effectively than the clinically-approved 5-LO inhibitor zileuton (IC50 3.5 µM, 95% CI 2.3–5.4 µM). CAPE was also more effective than zileuton for the inhibition of LT biosynthesis in PMNL but the compounds were equipotent in whole blood. The activity of the amide analogue of CAPE was similar to that of zileuton. Inhibition of LT biosynthesis by CAPE was the result of the inhibition of 5-LO and of AA release. Caffeic acid, CAPE and its amide analog were free radical scavengers and antioxidants with IC50 values in the low µM range; however, the phenethyl moiety of CAPE was required for effective inhibition of 5-LO and LT biosynthesis. Conclusions CAPE is a potent LT biosynthesis inhibitor that blocks 5-LO activity and AA release. The CAPE structure can be used as a framework for the rational design of stable and potent inhibitors of LT biosynthesis. PMID:22347509

Boudreau, Luc H.; Maillet, Jacques; LeBlanc, Luc M.; Jean-François, Jacques; Touaibia, Mohamed; Flamand, Nicolas; Surette, Marc E.

2012-01-01

56

Peripheral blood leukocytes of cows with subclinical endometritis show an altered cellular composition and gene expression.  

PubMed

Subclinical endometritis (SCE) is an important postpartum disease in dairy cows, but conventional cytobrush diagnosis often gives imprecise results. The aim of this study was to analyze disease-associated changes in peripheral blood as potential diagnostic parameters. Cellular subpopulations of blood leukocytes from cows with or without SCE (45-55 days postpartum) were flow-cytometrically quantified. Gene expression of whole blood leukocytes was assessed by PAXgene analysis. Subclinical endometritis cows showed significantly higher number of blood mononuclear cells and neutrophils. Among mononuclear cells, numbers of B-cells, NK-cells, and CD172a-positive monocytes were significantly elevated. Compared with non-SCE cows, blood leukocytes of SCE cows significantly expressed higher copy numbers of CXCL8, TNF, and IL12. To test whether circulating plasma factors are responsible for these changes, leukocytes, polymorphonuclear cells, and monocyte subpopulations (classical, intermediate, nonclassical) of healthy cows were stimulated with plasma of SCE and non-SCE cows. Although gene expression of whole leukocytes and polymorphonuclear cells remained unaltered, plasma from SCE animals significantly elevated expressed messenger RNA copy numbers of CXCL8, CXCL1, and IL1B in intermediate monocytes. In conclusion, elevated number of selected mononuclear subpopulations in peripheral blood and enhanced expression of distinct genes encoding for inflammatory mediators in blood leukocytes reflect the subclinical uterine inflammatory process in cows. Whether the observed changes in the periphery of SCE cows are the consequence of the uterine inflammatory process, or whether they affect the pathogenesis of the disease is currently unknown. PMID:24560452

Düvel, Anna; Maaß, Janine; Heppelmann, Maike; Hussen, Jamal; Koy, Mirja; Piechotta, Marion; Sandra, Olivier; Smith, David G E; Sheldon, Iain Martin; Dieuzy-Labaye, Isabelle; Zieger, Peter; Schuberth, Hans Joachim

2014-04-15

57

Propionate induces polymorphonuclear leukocyte activation and inhibits formylmethionyl-leucyl-phenylalanine-stimulated activation.  

PubMed Central

Short-chain carboxylic acids (SCCA) are metabolic by-products of bacterial pathogens which can alter cytoplasmic pH and inhibit a variety of polymorphonuclear leukocyte (PMN) motile functions. Since cytoskeletal F-actin alterations are central to PMN mobility, in this study we examined the effects of SCCA on cytoskeletal F-actin. Initially, we tested nine SCCA (formate, acetate, propionate, butyrate, valerate, caproate, lactate, succinate, and isobutyrate). We document here that while eight altered cytoplasmic pH, only six altered cytoskeletal F-actin. We then selected one SCCA that altered both F-actin and cytoplasmic pH (propionate) and one SCCA that altered only cytoplasmic pH (lactate) for further study. Propionate, but not lactate, caused an irregular cell shape and F-actin distribution. Furthermore, propionate, but not lactate, inhibited formylmethionyl-leucyl-phenylalanine (fMLP)-stimulated PMN polarization, F-actin localization, and cytoplasmic pH oscillation. Propionate-induced changes in cytoskeletal F-actin and cytoplasmic acidification were not affected by the fMLP receptor antagonist N-t-BOC-1-methionyl-1-leucyl-1-phenylalanine; however, alkalinization was affected. Pertussis toxin treatment completely inhibited propionate-induced changes in F-actin but had no effect on propionate-induced cytoplasmic pH oscillation. These results indicate that propionate (i) bypasses the fMLP receptor and G protein(s) to induce cytoplasmic pH oscillation, (ii) operates through G protein(s) to induce actin oscillation, cell shape changes (to irregular), and F-actin localization, and (iii) inhibits fMLP-stimulated cytoplasmic pH and actin oscillation, PMN polarization, and F-actin localization. Images PMID:1319407

Brunkhorst, B A; Kraus, E; Coppi, M; Budnick, M; Niederman, R

1992-01-01

58

Polymorphonuclear leukocytes restrict growth of Pseudomonas aeruginosa in the lungs of cystic fibrosis patients.  

PubMed

Cystic fibrosis (CF) patients have increased susceptibility to chronic lung infections by Pseudomonas aeruginosa, but the ecophysiology within the CF lung during infections is poorly understood. The aim of this study was to elucidate the in vivo growth physiology of P. aeruginosa within lungs of chronically infected CF patients. A novel, quantitative peptide nucleic acid (PNA) fluorescence in situ hybridization (PNA-FISH)-based method was used to estimate the in vivo growth rates of P. aeruginosa directly in lung tissue samples from CF patients and the growth rates of P. aeruginosa in infected lungs in a mouse model. The growth rate of P. aeruginosa within CF lungs did not correlate with the dimensions of bacterial aggregates but showed an inverse correlation to the concentration of polymorphonuclear leukocytes (PMNs) surrounding the bacteria. A growth-limiting effect on P. aeruginosa by PMNs was also observed in vitro, where this limitation was alleviated in the presence of the alternative electron acceptor nitrate. The finding that P. aeruginosa growth patterns correlate with the number of surrounding PMNs points to a bacteriostatic effect by PMNs via their strong O2 consumption, which slows the growth of P. aeruginosa in infected CF lungs. In support of this, the growth of P. aeruginosa was significantly higher in the respiratory airways than in the conducting airways of mice. These results indicate a complex host-pathogen interaction in chronic P. aeruginosa infection of the CF lung whereby PMNs slow the growth of the bacteria and render them less susceptible to antibiotic treatment while enabling them to persist by anaerobic respiration. PMID:25114118

Kragh, Kasper N; Alhede, Morten; Jensen, Peter Ø; Moser, Claus; Scheike, Thomas; Jacobsen, Carsten S; Seier Poulsen, Steen; Eickhardt-Sørensen, Steffen Robert; Trøstrup, Hannah; Christoffersen, Lars; Hougen, Hans-Petter; Rickelt, Lars F; Kühl, Michael; Høiby, Niels; Bjarnsholt, Thomas

2014-11-01

59

Characterization of receptors for platelet-activating factor on platelets, polymorphonuclear leukocytes and macrophages.  

PubMed Central

1. We have compared the potency of the putative platelet-activating factor (Paf) receptor antagonists (WEB 2086, L-652,731 and BN 52021) against Paf-induced aggregation of rabbit and guinea-pig platelets, aggregation of rabbit polymorphonuclear leukocytes (PMNLs) and prostacyclin generation by guinea-pig resident peritoneal macrophages. 2. On rabbit washed platelets and PMNLs WEB 2086, L-652,731 and BN 52021 each antagonized competitively Paf-induced aggregation. The rank order of potency was WEB 2086 congruent to L-652,731 greater than BN 52021 and was the same for the two cell types. 3. The pA2 values for each of the three antagonists were similar on rabbit washed platelets and PMNLs. Moreover, the pA2 for WEB 2086 on rabbit platelets (7.58) did not differ significantly from that on guinea-pig platelets (7.69). 4. On guinea-pig resident peritoneal macrophages WEB 2086 was 10 fold less potent for receptors mediating increased generation of 6-oxo-prostaglandin F1 alpha (6-oxo-PGF1 alpha) than for those mediating platelet aggregation. 5. The potencies of L-652,731 and BN 52021 were also markedly less (2 log units) for the macrophage receptors than for platelet or PMNL receptors and BN 52021 was more potent than L-652,731 in the macrophages. 6. WEB 2086 and L-652,731 significantly reduced basal 6-oxo-PGF1 alpha produced by macrophages, but none of the antagonists affected 6-oxo-PGF1 alpha production during stimulation by A23187. 7. These data raise the possibility that there may be a Paf receptor-subtype mediating prostacyclin generation in macrophages that is different from that on the platelet and PMNL.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2850058

Stewart, A. G.; Dusting, G. J.

1988-01-01

60

Role of Yersinia pestis Toxin Complex Family Proteins in Resistance to Phagocytosis by Polymorphonuclear Leukocytes  

PubMed Central

Yersinia pestis carries homologues of the toxin complex (Tc) family proteins, which were first identified in other Gram-negative bacteria as having potent insecticidal activity. The Y. pestis Tc proteins are neither toxic to fleas nor essential for survival of the bacterium in the flea, even though tc gene expression is highly upregulated and much more of the Tc proteins YitA and YipA are produced in the flea than when Y. pestis is grown in vitro. We show that Tc+ and Tc? Y. pestis strains are transmitted equivalently from coinfected fleas, further demonstrating that the Tc proteins have no discernible role, either positive or negative, in transmission by the flea vector. Tc proteins did, however, confer Y. pestis with increased resistance to killing by polymorphonuclear leukocytes (PMNs). Resistance to killing was not the result of decreased PMN viability or increased intracellular survival but instead correlated with a Tc protein-dependent resistance to phagocytosis that was independent of the type III secretion system (T3SS). Correspondingly, we did not detect T3SS-dependent secretion of the native Tc proteins YitA and YipA or the translocation of YitA– or YipA–?-lactamase fusion proteins into CHO-K1 (CHO) cells or human PMNs. Thus, although highly produced by Y. pestis within the flea and related to insecticidal toxins, the Tc proteins do not affect interaction with the flea or transmission. Rather, the Y. pestis Tc proteins inhibit phagocytosis by mouse PMNs, independent of the T3SS, and may be important for subverting the mammalian innate immune response immediately following transmission from the flea. PMID:23959716

Carmody, Aaron B.; Jarrett, Clayton O.; Hinnebusch, B. Joseph

2013-01-01

61

Coxiella burnetii acid phosphatase inhibits the release of reactive oxygen intermediates in polymorphonuclear leukocytes.  

PubMed

Coxiella burnetii, the etiological agent of Q fever, is a small, Gram-negative, obligate intracellular bacterium. Replication of C. burnetii during infection has been shown to be increased by decreasing oxidative stress using p47(phox -/-) and iNOS(-/-) mice in vivo and by pharmacologic inhibitors in vitro. Building upon this model, we investigated the role polymorphonuclear leukocytes (PMN) play in the control of infection, since NADPH oxidase-mediated release of reactive oxygen intermediates (ROI) is a primary bactericidal mechanism for these cells that is critical for early innate clearance. Earlier studies suggested that C. burnetii actively inhibited release of ROI from PMN through expression of an unidentified acid phosphatase (ACP). Recent genomic annotations identified one open reading frame (CBU0335) which may encode a Sec- and type II-dependent secreted ACP. To test this model, viable C. burnetii propagated in tissue culture host cells or axenic media, C. burnetii extracts, or purified recombinant ACP (rACP) was combined with human PMN induced with 4-phorbol 12-myristate 13-acetate (PMA). The release of ROI was inhibited when PMN were challenged with viable C. burnetii, C. burnetii extracts, or rACP but not when PMN were challenged with electron beam-inactivated C. burnetii. C. burnetii extracts and rACP were also able to inhibit PMA-induced formation of NADPH oxidase complex on PMN membranes, suggesting a molecular mechanism responsible for this inhibition. These data support a model in which C. burnetii eludes the primary ROI killing mechanism of activated PMN by secreting at least one acid phosphatase. PMID:21078859

Hill, J; Samuel, J E

2011-01-01

62

Coxiella burnetii Acid Phosphatase Inhibits the Release of Reactive Oxygen Intermediates in Polymorphonuclear Leukocytes ?  

PubMed Central

Coxiella burnetii, the etiological agent of Q fever, is a small, Gram-negative, obligate intracellular bacterium. Replication of C. burnetii during infection has been shown to be increased by decreasing oxidative stress using p47phox ?/? and iNOS?/? mice in vivo and by pharmacologic inhibitors in vitro. Building upon this model, we investigated the role polymorphonuclear leukocytes (PMN) play in the control of infection, since NADPH oxidase-mediated release of reactive oxygen intermediates (ROI) is a primary bactericidal mechanism for these cells that is critical for early innate clearance. Earlier studies suggested that C. burnetii actively inhibited release of ROI from PMN through expression of an unidentified acid phosphatase (ACP). Recent genomic annotations identified one open reading frame (CBU0335) which may encode a Sec- and type II-dependent secreted ACP. To test this model, viable C. burnetii propagated in tissue culture host cells or axenic media, C. burnetii extracts, or purified recombinant ACP (rACP) was combined with human PMN induced with 4-phorbol 12-myristate 13-acetate (PMA). The release of ROI was inhibited when PMN were challenged with viable C. burnetii, C. burnetii extracts, or rACP but not when PMN were challenged with electron beam-inactivated C. burnetii. C. burnetii extracts and rACP were also able to inhibit PMA-induced formation of NADPH oxidase complex on PMN membranes, suggesting a molecular mechanism responsible for this inhibition. These data support a model in which C. burnetii eludes the primary ROI killing mechanism of activated PMN by secreting at least one acid phosphatase. PMID:21078859

Hill, J.; Samuel, J. E.

2011-01-01

63

Increased activity of 5-lipoxygenase in polymorphonuclear leukocytes from asthmatic patients  

SciTech Connect

The formation of 5-lipoxygenase products of arachidonic acid, 5-HETE and 5,12-diHETE, was determined in 100,000 x g supernatant of polymorphonuclear leukocytes from 17 healthy subjects, 17 patients with extrinsic asthma and 15 patients with intrinsic asthma. After the supernatant was incubated with /sup 14/C-arachidonic acid in the presence of calcium and indomethacin, the lipoxygenase products of arachidonic acid were separated by thin layer chromatography. The results were expressed as the percentage conversion of /sup 14/C-arachidonic acid into the product per 10/sup 7/ cells. The formation of 5,12-diHETE, but not of the 5-HETE, was significantly increased in the cells from the group of patients with extrinsic asthma (4.38 +/- 0.78%, mean +/- S.E.; p < 0.01) and intrinsic asthma (6.09 +/- 1.11%; p < 0.01), when compared to normal subjects (1.74 +/- 0.30%). Both extrinsic and intrinsic asthmatics had significantly enhanced 5-lipoxygenase activity, which was expressed as the sum of percentage conversion of /sup 14/C-arachidonic acid into 5-HETE and 5,12-diHETE. The percentage conversion in normal subjects was 4.19 +/- 0.39%, 6.24 +/- 0.84% for 17 patients with extrinsic asthma (p < 0.05), and 8.59 +/- 1.29% for 15 patients with intrinsic asthma (p < 0.01). There was no significant difference between these asthmatic groups. These results indicate that 5-lipoxygenase activity is increased in patients with bronchial asthma. 22 references, 3 figures.

Mita, H.; Yui, Y.; Taniguchi, N.; Yasueda, H.; Shida, T.

1985-09-09

64

Benidipine, an anti-hypertensive drug, inhibits reactive oxygen species production in polymorphonuclear leukocytes and oxidative stress in salt-loaded stroke-prone spontaneously hypertensive rats.  

PubMed

Oxidative stress is associated with exacerbation of renal injuries in hypertension. In clinical studies benidipine hydrochloride (benidipine), a dihydropyridine calcium channel blocker with antioxidant activity, reduced oxidative stress. However, the mechanism of suppression of oxidative stress remains to be fully characterized. Reactive oxygen species production by polymorphonuclear leukocyte plays important pathological roles in hypertension. Therefore, we examined the effects of benidipine both on reactive oxygen species production of human polymorphonuclear leukocytes and oxidative stress of an animal model. Human peripheral polymorphonuclear leukocytes or polymorphonuclear leukocyte-like differentiated HL-60 cells were used to examine effects of benidipine (0.1-30 microM) on formyl-Met-Leu-Phe-induced reactive oxygen species production, calcium mobilization, NADPH oxidase activation and phosphorylation of protein kinase C substrates. High-salt (8% NaCl) loaded stroke-prone spontaneously hypertensive rats were treated with or without benidipine (1, 3, 10 mg/kg/day) for 2 weeks, and thiobarbituric acid reactive substances, a plasma oxidative stress marker, and renal expression of oxidative stress-induced genes were measured. Benidipine concentration-dependently suppressed formyl-Met-Leu-Phe-induced reactive oxygen species production in polymorphonuclear leukocytes more potently than other calcium channel blockers such as amlodipine, azelnidipine, nitrendipine and nifedipine. Benidipine partially inhibited all of intracellular Ca(2+) elevation, protein kinase C activation and NADPH oxidase activation. Salt loading in stroke-prone spontaneously hypertensive rats augmented plasma thiobarbituric acid reactive substances levels; renal dysfunction; and renal expression of transforming growth factor-beta, collagen I and collagen III mRNAs; which were attenuated by benidipine treatment. These results indicate that benidipine prevents the polymorphonuclear leukocyte-derived reactive oxygen species production, which is due at least in part to its antioxidant action and inhibition of Ca(2+)/protein kinase C/NADPH oxidase signaling. The attenuation of reactive oxygen species production might contribute to the drug's reduction of oxidative stress and renal injuries in hypertension. PMID:18048030

Matsubara, Masahiro; Akizuki, Osamu; Ikeda, Jun-ichi; Saeki, Koji; Yao, Kozo; Sasaki, Katsutoshi

2008-02-01

65

Dendritic Cells Take up and Present Antigens from Viable and Apoptotic Polymorphonuclear Leukocytes  

PubMed Central

Dendritic cells (DC) are endowed with the ability to cross-present antigens from other cell types to cognate T cells. DC are poised to meet polymorphonuclear leukocytes (PMNs) as a result of being co-attracted by interleukin-8 (IL-8), for instance as produced by tumor cells or infected tissue. Human monocyte-derived and mouse bone marrow-derived DC can readily internalize viable or UV-irradiated PMNs. Such internalization was abrogated at 4°C and partly inhibited by anti-CD18 mAb. In mice, DC which had internalized PMNs containing electroporated ovalbumin (OVA) protein, were able to cross-present the antigen to CD8 (OT-1) and CD4 (OT-2) TCR-transgenic T cells. Moreover, in humans, tumor cell debris is internalized by PMNs and the tumor-cell material can be subsequently taken up from the immunomagnetically re-isolated PMNs by DC. Importantly, if human neutrophils had endocytosed bacteria, they were able to trigger the maturation program of the DC. Moreover, when mouse PMNs with E. coli in their interior are co-injected in the foot pad with DC, many DC loaded with fluorescent material from the PMNs reach draining lymph nodes. Using CT26 (H-2d) mouse tumor cells, it was observed that if tumor cells are intracellularly loaded with OVA protein and UV-irradiated, they become phagocytic prey of H-2d PMNs. If such PMNs, that cannot present antigens to OT-1 T cells, are immunomagnetically re-isolated and phagocytosed by H-2b DC, such DC productively cross-present OVA antigen determinants to OT-1 T cells. Cross-presentation to adoptively transferred OT-1 lymphocytes at draining lymph nodes also take place when OVA-loaded PMNs (H-2d) are coinjected in the footpad of mice with autologous DC (H-2b). In summary, our results indicate that antigens phagocytosed by short-lived PMNs can be in turn internalized and productively cross-presented by DC. PMID:22206007

Alfaro, Carlos; Suarez, Natalia; Oñate, Carmen; Perez-Gracia, Jose L.; Martinez-Forero, Ivan; Hervas-Stubbs, Sandra; Rodriguez, Inmaculada; Perez, Guiomar; Bolaños, Elixabet; Palazon, Asis; de Sanmamed, Miguel Fernandez; Morales-Kastresana, Aizea; Gonzalez, Alvaro; Melero, Ignacio

2011-01-01

66

Oxidative inactivation of leukotriene C4 by stimulated human polymorphonuclear leukocytes.  

PubMed

Leukotriene C(4) (LTC(4)) was metabolized by human polymorphonuclear leukocytes (PMNs) stimulated with phorbol myristate acetate (PMA) into three sets of products. These products differed in mobility on reverse-phase high-performance liquid chromatography (RP HPLC) from LTC(4) and also from leukotriene D(4) (LTD(4)) and leukotriene E(4) (LTE(4)), the sequential products of peptide cleavage of LTC(4). Products I, II, and III were eluted as doublets with an average retention time for each doublet of 7.5 +/- 0.3, 10.5 +/- 0.6, and 16.3 +/- 1.1 min (mean +/- SD), respectively, as compared with 13.8 min for LTC(4). Doublet I material was biologically inactive and showed <5% of the immunoreactivity of LTC(4), doublet II material had 1% of the spasmogenic activity of LTC(4) on the guinea pig ileum and was equally immunoreactive, and doublet III material was neither biologically active nor immunoreactive. When [14,15-(3)H]LTC(4) and [(35)S]LTC(4) were metabolized, all three doublet products retained the (3)H label, whereas only the doublet I and doublet II products retained the (35)S label. The UV absorbance spectra of the three sets of metabolites were as follows: doublet I, maximum at 280 nm with shoulders at about 270 and 290 nm; doublet II, maximum at 284.5 nm with shoulders at about 275 and 295 nm; and doublet III, maximum at 269 nm with shoulders at about 259 and 279 nm. The metabolism of LTC(4) to the three classes of functionally inactive products by stimulated PMNs was completely blocked by catalase and azide, indicating a requirement for H(2)O(2) and myeloperoxidase. When hypochlorous acid (HOCl)-considered to be a natural product of the interaction of myeloperoxidase, H(2)O(2), and chloride ion-was formed chemically and allowed to react with LTC(4), the resulting products were indistinguishable by UV and HPLC analyses from the doublet II and doublet III metabolites of LTC(4). The doublet II products were identified as the two diastereoisomeric sulfoxides of LTC(4) by comparison with synthetic reference compounds. The doublet III products were shown to be identical with synthetic samples of (5S, 12S)- and (5S, 12R)-6-trans-LTB(4). The formation of two diastereoisomeric LTC(4) sulfoxides and 6-trans-LTB(4) can be explained in terms of an S-chlorosulfonium ion as the initial reactive intermediate, which subsequently undergoes conversion to product II by hydrolysis and product III by carbocation formation. PMID:6955794

Lee, C W; Lewis, R A; Corey, E J; Barton, A; Oh, H; Tauber, A I; Austen, K F

1982-07-01

67

Cytotoxicity of human peripheral blood and colostral leukocytes against Shigella species.  

PubMed Central

We examined the ability of human peripheral blood leukocytes to kill strains of Shigella sonnei and Shigella flexneri by using a modified bactericidal assay. Antibody-dependent cellular cytotoxicity (ADCC) was demonstrated in the presence of specific rabbit immune serum directed against S. sonnei. With peripheral blood leukocytes from adults, ADCC was found only in the mononuclear cell and purified lymphocyte populations. Monocyte-macrophages and polymorphonuclear leukocytes were unable to demonstrate ADCC. Lymphocyte ADCC, which was not affected by the addition of phenylbutazone (an inhibitor of phagocytosis), was mediated by a non-T, Fc receptor-positive, HNK-1- cell. ADCC (using antiserum directed against virulent S. sonnei) was demonstrated against virulent S. sonnei but not against virulent S. sonnei or virulent S. flexneri. In contrast to leukocytes from adults, both mononuclear and polymorphonuclear cells from neonatal cord blood and from a patient with chronic granulomatous disease mediated anti-Shigella ADCC. Breast milk leukocytes (BMLs) collected 1 to 3 days postpartum were used as effector cells against virulent S. sonnei. The entire BML population, BMLs which did not adhere to plastic and BMLs which passed through nylon wool columns mediated both natural killer cytotoxicity and ADCC. In paired experiments, natural killer cytotoxicity and ADCC were significantly lower (30 to 45% inhibition) but not ablated, when phenylbutazone was added to BMLs and nylon wool-purified BMLs (P less than 0.05). These experiments suggest that colostral leukocytes mediated both extracellular and intracellular bacteriolysis in the presence and absence of specific antiserum. These mechanisms may be active in vivo in protection against shigellosis. PMID:6384045

Morgan, D R; DuPont, H L; Gonik, B; Kohl, S

1984-01-01

68

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

PubMed Central

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 ?mol/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 ?mol/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 glutathione peroxidase. However, the cytotoxic effect of ADM in K562 cells was not significantly altered by naringenin, and the oxidative stress indices in K562 cells remained stable. In conclusion, the present study revealed the promising value of naringenin in leukemia treatment. Naringenin demonstrated a significant inhibitory effect on the growth of K562 cells but not on normal PMNs. Furthermore, naringenin protected PMNs from ADM-induced oxidative damage at low concentrations. Cell cycle arrest and apoptosis-inducing effects, achieved through p53-independent p21/WAF1 upregulation, are likely to be the mechanism of the antileukemic effects of naringenin, and the protective effect against ADM chemotherapy-induced damage in PMNs may be due to the antioxidant capability of this agent at low concentrations. PMID:25667616

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

2015-01-01

69

Lateral diffusion of plasma membrane receptors labelled with either platelet-derived growth factor (PDGF) or wheat germ agglutinin (WGA) in human polymorphonuclear leukocytes and fibroblasts  

Microsoft Academic Search

The aims of the present investigation were (a) to compare the lateral mobility of membrane receptors of human fibroblasts and polymorphonuclear leukocytes (PMNL) labelled with either platelet-derived growth factor (PDGF), or the lectin wheat germ agglutinin (WGA), and (b) to study effects of serum or PDGF on the mobility of these receptor molecules in human fibroblasts. Human foreskin fibroblasts (AG

Pia Ljungquist; Åke Wasteson; Karl-Eric Magnusson

1989-01-01

70

Comparison of the antioxidant properties of wound dressing materials–carboxymethylcellulose, hyaluronan benzyl ester and hyaluronan, towards polymorphonuclear leukocyte-derived reactive oxygen species  

Microsoft Academic Search

In chronic wounds, factors are released which perpetuate inflammatory processes, including polymorphonuclear leukocyte (PMN)-derived reactive oxygen species (ROS), such as superoxide radical (O2?) and hydroxyl radical (OH) species. The glycosaminoglycan, hyaluronan, has established antioxidant properties towards ROS, although the antioxidant potential of wound dressing biomaterials, such as 75% benzyl esterified hyaluronan (BEHA) and carboxymethylcellulose (CMCH), are less characterised. This study

R. Moseley; M. Walker; R. J. Waddington; W. Y. J. Chen

2003-01-01

71

Blood leukocyte and spleen lymphocyte immune response of spleen lymphocytes and whole blood leukocytes of hamsters  

SciTech Connect

This study was designed to evaluate the effects of chronic physical activity on the immune response of spleen lymphocytes and whole blood leukocytes of hamsters. Animals were kept sedentary or allowed to exercise spontaneously on running wheels for eight weeks. Physically active animals averaged 12 kilometers per day. The immune response of spleen lymphocytes whole blood leukocytes was evaluated by {sup 3}H-thymidine incorporation in response to Concanavalin A or lipopolysaccharide. There was no treatment effect between physically active and sedentary hamster in response of spleen lymphocytes. The immune response of whole blood leukocytes to these mitogens was significantly greater in physically active vs. sedentary hamsters. These results demonstrate that chronic physical activity has the capacity to modulate immunoresponses.

Peters, B.A.; Sothmann, M.; Wehrenberg, W.B. (Univ. of Wisconsin, Milwaukee (USA))

1989-01-01

72

[Influence of nonsteroidal anti-inflammatory drugs on chemiluminescence of polymorphonuclear leukocytes in patients with intolerance of these drugs].  

PubMed

We have studied the intensity of barium sulfate stimulated luminol- and lucigenin-dependent chemiluminescence (SLCHL and SLCCHL) in polymorphonuclear leukocytes (PML) after pre-incubation of PML suspension with sodium salicylate, sodium metamizole, or sodium diclofenac at various concentrations in healthy donors and patients with intolerance to aspirin, and/or sodium metamizole, and/or sodium diclofenac. No significant differences of SLCHL and SLCCHL indicators in PML isolated from healthy donors and patients with intolerance to these drugs have been found, which indirectly indicates the absence of any specific features in the oxidative metabolism of PML enzymes under the influence of indicated NSAIDs in patients intolerant of these drugs as compared to donors. PMID:25033569

2014-01-01

73

In Vitro Correlates of Delayed Hypersensitivity in Man: Ambiguity of Polymorphonuclear Neutrophils as Indicator Cells in Leukocyte Migration Test  

PubMed Central

Delayed cutaneous hypersensitivity (DCH) of 12 normal adult subjects to purified protein derivative (PPD) of Mycobacterium tuberculosis, streptococcal streptokinase-streptodornase (SK-SD), and Candida albicans Dermatophytin O (DO) was assayed in vivo by skin testing and compared with such in vitro correlates of cellular immunity as lymphocyte transformation (LT) and inhibition of leukocyte migration (ILM) from microcapillary tubes or in agarose gel. LT was shown to be the best in vitro correlate of specific lymphocyte sensitization with all antigens. In the ILM assays, PPD showed good correlation with in vivo DCH and in vitro LT; SK-SD showed partial correlation; DO showed no correlation, not being active in any of the ILM tests. Cell distribution and morphology of stained migration patterns, ILM tests performed on separated populations of lymphocytes and polymorphonuclear leukocytes (PMN), as well as the ability of test antigens to stimulate PMN cells to reduce nitroblue-tetrazolium dye, indicated that in ILM tests mononuclear cells were not inhibited in their migration, whereas migration of PMN cells appeared to depend on their direct reaction with the test antigens. Images PMID:4581009

Senyk, George; Hadley, W. Keith

1973-01-01

74

Modulation of polymorphonuclear neutrophil functions by astrocytes  

Microsoft Academic Search

BACKGROUND: Neuroinflammation is a complex process involving cells from the immune system and the central nerve system (CNS). Polymorphonuclear neutrophils (PMN) are the most abundant class of white blood cells, and typically the first type of leukocyte recruited to sites of inflammation. In the CNS, astrocytes are the most abundant glial cell population and participate in the local innate immune

Luokun Xie; Ethan C Poteet; Wenjun Li; Amanda E Scott; Ran Liu; Yi Wen; Anuja Ghorpade; James W Simpkins; Shao-Hua Yang

2010-01-01

75

Interaction of inflammatory cells and oral microorganisms. IV. In vitro release of lysosomal constituents from polymorphonuclear leukocytes exposed to supragingival and subgingival bacterial plaque.  

PubMed Central

The deposition of bacterial plaques on tooth surfaces appears to be responsible for the initiation and progression of periodontal disease. In this study, human peripheral blood polymorphonuclear leukocytes (PMNs) actively released lysosomal constituents upon in vitro exposure to either viable or irradiated, supragingival or subgingival dental plaque. Plaques were obtained from the PMN donors (autologous plaque) or from pooled samples (homologous plaque) secured from patients with periodontal lesions. Fresh sera from PMN donors amplified the release reactions to supragingival and subgingival plaques. Heated (56 degrees C, 30 min) sera also enhanced release reactions, but not as consistently as fresh serum. It was postulated that modulation of PMN release by serum is mediated by complement components and/or antibodies to plaque bacteria. Electron microscopic observations indicated that degranulation and discharge of PMN lysosomal enzymes may be associated with phagocytosis of gram-positive and gram-negative plaque bacteria and with reverse endocytosis of lysosomes from cells contacting relatively large masses of aggregated plaque bacteria. These data suggest that PMN lysosome release in response to plaque may serve as a potential mechanism of tissue injury in the pathogenesis of gingival and periodontal inflammation. Images PMID:197005

Taichman, N S; Tsai, C C; Baehni, P C; Stoller, N; McArthur, W P

1977-01-01

76

Phagocytic response of bovine polymorphonuclear leukocytes to different incubation conditions and following exposure to some effectors of phagocytosis and different anticoagulants in vitro.  

PubMed Central

The ability of bovine polymorphonuclear leukocytes (PMN) to phagocytose fluorescent beads in vitro was studied using flow cytometry. The effects of varying laboratory conditions (bead:PMN ratio, length of incubation, and temperature) were first determined, then the effects of lipopolysaccharide (LPS), phorbol myristate acetate (PMA), cytochalasin B, and formyl-met-leu-phe (fMLP) on phagocytosis were evaluated. The recommended bead:PMN ratio, incubation period, and incubation temperature are 20:1, 30 min, and 38.5 degrees C, respectively. Lipopolysaccharide increased phagocytosis at a relatively high minimum dose; PMA increased phagocytosis even at low doses; cytochalasin B increased and decreased phagocytosis at low and high doses, respectively; and fMLP had no significant effect on phagocytosis. Also, the effects of ethylene diamine tetraacetic acid (EDTA) and acid citrate dextrose (ACD) as anticoagulants were compared with heparin-treated blood PMNs. Both EDTA and ACD decreased phagocytosis. Although there are reports that demonstrated that heparin reduced PMN phagocytosis, at least among the 3 anticoagulants used, heparin remains to be the standard anticoagulant for the study of PMN phagocytosis. Images Figure 1. PMID:11227193

Ducusin, R J; Sarashina, T; Uzuka, Y; Tanabe, S; Ohtani, M

2001-01-01

77

In vitro regulation of Mac-1 expression on bovine polymorphonuclear leukocytes by endotoxin and tumor necrosis factor-? at different stages of lactation  

PubMed Central

Abstract The purpose of this in vitro study is to clarify some of the underlying mechanisms leading to the decreased migratory capacity of polymorphonuclear leukocytes (PMN) during mastitis in dairy cows soon after calving. Surface expression of Mac-1 (CD11b, CR3) on PMN and of CD14 on monocytes was measured in early- (EL), peak- (PL), and midlactation (ML) by flow cytometric analysis. In addition, we evaluated the effect of lipopolysaccharide (LPS) and tumor necrosis factor (TNF)-? on CD11b surface expression in PMN at different stages of lactation in a whole blood model. During EL, while resting monocytes expressed diminished levels of CD14, the basal expression of CD11b on PMN was not significantly altered. The relative increase of CD11b on PMN after incubation with LPS or TNF-? did not significantly differ among EL, PL, or ML at any of the concentrations tested. The current findings do not support an important role for basal CD11b levels nor for a defective mobilization of CD11b by LPS and TNF-? in the reduced migratory capacity of PMN during EL. PMID:15352552

2004-01-01

78

Role of the Yersinia pestis Ail Protein in Preventing a Protective Polymorphonuclear Leukocyte Response during Bubonic Plague?  

PubMed Central

The ability of Yersinia pestis to forestall the mammalian innate immune response is a fundamental aspect of plague pathogenesis. In this study, we examined the effect of Ail, a 17-kDa outer membrane protein that protects Y. pestis against complement-mediated lysis, on bubonic plague pathogenesis in mice and rats. The Y. pestis ail mutant was attenuated for virulence in both rodent models. The attenuation was greater in rats than in mice, which correlates with the ability of normal rat serum, but not mouse serum, to kill ail-negative Y. pestis in vitro. Intradermal infection with the ail mutant resulted in an atypical, subacute form of bubonic plague associated with extensive recruitment of polymorphonuclear leukocytes (PMN or neutrophils) to the site of infection in the draining lymph node and the formation of large purulent abscesses that contained the bacteria. Systemic spread and mortality were greatly attenuated, however, and a productive adaptive immune response was generated after high-dose challenge, as evidenced by high serum antibody levels against Y. pestis F1 antigen. The Y. pestis Ail protein is an important bubonic plague virulence factor that inhibits the innate immune response, in particular the recruitment of a protective PMN response to the infected lymph node. PMID:21969002

Hinnebusch, B. Joseph; Jarrett, Clayton O.; Callison, Julie A.; Gardner, Donald; Buchanan, Susan K.; Plano, Gregory V.

2011-01-01

79

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

SciTech Connect

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.

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

1987-11-01

80

The effect of low levels of dietary cobalt on the chemiluminescence response of polymorphonuclear leukocytes of goats.  

PubMed

Twenty ten-week-old newly weaned male Batinah goats were randomly assigned to a control (n=10) and a treated (n=10) group and were fed a diet containing 0.1mg/kg DM cobalt (Co). Goats in the treated group received bi-monthly subcutaneous injections of 2000 microg of hydroxycobalamin. The phagocytic function of the polymorphonuclear leukocytes (PMN) were tested using a luminol-dependent chemiluminescence assay with opsonized zymosan as the phagocytic target. One month after the onset of the experiment PMN from the control group exhibited a significantly (p<0.05) lower CL response, which continued for the second month. The results of the present study demonstrated that low levels of dietary cobalt leads to an early impairment of phagocytic function. This may at least in part, be an explanation as to why at the field level in Oman young goats fed diets containing low levels of Co appear to be more susceptible to infections. PMID:19679325

Johnson, Eugene H; Al-Habsi, Khalid; Al-Busaidy, Rashid; Khalaf, Samera Kasim

2010-02-01

81

Pseudomonas aeruginosa variants isolated from patients with cystic fibrosis are killed by a bactericidal protein from human polymorphonuclear leukocytes.  

PubMed Central

The susceptibility of paired mucoid and nonmucoid variants of Pseudomonas aeruginosa isolated from 13 patients with cystic fibrosis (CF) to killing by a 55,000-Da bactericidal protein (BP55) from human polymorphonuclear leukocytes was studied. Mucoid and nonmucoid variants were equally sensitive to killing by BP55 at both pH 5.6 and pH 7.2. Eleven of the isolates were resistant to the bactericidal activity of 10% normal human serum but were as sensitive as the serum-sensitive isolates to BP55. Similarly, the 15 isolates with lipopolysaccharides (LPS) containing O-polysaccharide side chains (smooth LPS) were as sensitive to BP55 as those isolates with rough LPS.P. aeruginosa isolates from patients in poor clinical condition were more likely to have LPS of the smooth type and to be resistant to killing by 10% human serum than the isolates from patients in good clinical condition. We have concluded that the susceptibility of the P. aeruginosa isolates from patients with CF to killing by BP55 does not correlate with mucoid or nonmucoid variations, with the presence or absence of smooth LPS, or with the sensitivity or resistance to killing by normal human serum. Images PMID:1903774

Siefferman, C M; Regelmann, W E; Gray, B H

1991-01-01

82

Role of the Yersinia pestis Ail protein in preventing a protective polymorphonuclear leukocyte response during bubonic plague.  

PubMed

The ability of Yersinia pestis to forestall the mammalian innate immune response is a fundamental aspect of plague pathogenesis. In this study, we examined the effect of Ail, a 17-kDa outer membrane protein that protects Y. pestis against complement-mediated lysis, on bubonic plague pathogenesis in mice and rats. The Y. pestis ail mutant was attenuated for virulence in both rodent models. The attenuation was greater in rats than in mice, which correlates with the ability of normal rat serum, but not mouse serum, to kill ail-negative Y. pestis in vitro. Intradermal infection with the ail mutant resulted in an atypical, subacute form of bubonic plague associated with extensive recruitment of polymorphonuclear leukocytes (PMN or neutrophils) to the site of infection in the draining lymph node and the formation of large purulent abscesses that contained the bacteria. Systemic spread and mortality were greatly attenuated, however, and a productive adaptive immune response was generated after high-dose challenge, as evidenced by high serum antibody levels against Y. pestis F1 antigen. The Y. pestis Ail protein is an important bubonic plague virulence factor that inhibits the innate immune response, in particular the recruitment of a protective PMN response to the infected lymph node. PMID:21969002

Hinnebusch, B Joseph; Jarrett, Clayton O; Callison, Julie A; Gardner, Donald; Buchanan, Susan K; Plano, Gregory V

2011-12-01

83

Pseudomonas aeruginosa variants isolated from patients with cystic fibrosis are killed by a bactericidal protein from human polymorphonuclear leukocytes.  

PubMed

The susceptibility of paired mucoid and nonmucoid variants of Pseudomonas aeruginosa isolated from 13 patients with cystic fibrosis (CF) to killing by a 55,000-Da bactericidal protein (BP55) from human polymorphonuclear leukocytes was studied. Mucoid and nonmucoid variants were equally sensitive to killing by BP55 at both pH 5.6 and pH 7.2. Eleven of the isolates were resistant to the bactericidal activity of 10% normal human serum but were as sensitive as the serum-sensitive isolates to BP55. Similarly, the 15 isolates with lipopolysaccharides (LPS) containing O-polysaccharide side chains (smooth LPS) were as sensitive to BP55 as those isolates with rough LPS.P. aeruginosa isolates from patients in poor clinical condition were more likely to have LPS of the smooth type and to be resistant to killing by 10% human serum than the isolates from patients in good clinical condition. We have concluded that the susceptibility of the P. aeruginosa isolates from patients with CF to killing by BP55 does not correlate with mucoid or nonmucoid variations, with the presence or absence of smooth LPS, or with the sensitivity or resistance to killing by normal human serum. PMID:1903774

Siefferman, C M; Regelmann, W E; Gray, B H

1991-06-01

84

Age-related comparison of superoxide production by canine neutrophilic polymorphonuclear leukocytes  

E-print Network

of respiratory burst activi ty may not always correlate wi th another measure. For example, in the canine granulocytopathy syndrome HMPS activity is decreased in PMNs from affected dogs, whereas, nitroblue tetrazolium (NBT) dye reduction is increased (65, 67.... Cell. Res. 87: 392-394. 57. Paape, M. J. , W. P. Wergin, A. J . Gui dry, and R. E. Pearson. 1 979 . Leukocytes-second line of defense against invading mastiti s pathogens. J. Dairy Sci. , 62: 135-153. 58. Paul, B. B. , R. R. Strauss, A. A. Jacobs...

Hanson, Thomas Dale

1983-01-01

85

Alkaline phosphatase activity of polymorphonuclear leucocytes and lymphocytes separated from normal human blood  

Microsoft Academic Search

Suspensions of polymorphonuclear leucocytes and lymphocytes were prepared from normal human blood by the glass bead column method of Rabinowitz (1964). The alkaline phosphatase activity of the separated cells was determined by biochemical and cytochemical techniques.Lymphocytes were found to contain an enzyme catalysing the hydrolysis of ?-glycerophosphate at alkaline pH but not of p-nitrophenylphosphate at the same pH and in

Judith K. Park

1970-01-01

86

Polymorphonuclear leukocytes induce PDGF release from IL-1beta-treated endothelial cells: role of adhesion molecules and serine proteases.  

PubMed

Polymorphonuclear leukocytes (PMNs) and endothelial cells interact at sites of vascular injury during inflammatory response and during the development of atherosclerotic lesions. Such close proximity leads to the modulation of several of the biological functions of the 2 cell types. Because we have shown previously that PMNs enhance release of growth factors from resting endothelial cells, we decided to evaluate whether coincubation of PMNs with interleukin-1beta (IL-1beta)-stimulated human umbilical vein endothelial cells (HUVEC) could further modulate mitogen release from HUVEC. We found that PMN-HUVEC coincubation resulted in a 10-fold increase in mitogen release, compared with HUVEC alone (14+/-6 versus 1.3+/-0.1). When PMNs were incubated with IL-1beta-treated HUVEC, a further increase in mitogen release (up to 35-fold) was observed. The mitogenic activity was immunologically related to platelet-derived growth factor (PDGF) because the activity was abolished by an anti-PDGF antibody. PDGF-AB antigen, detected in low concentrations in conditioned medium from HUVEC alone, was increased 4-fold when IL-1beta or PMNs were incubated with HUVEC and dramatically upregulated (up to 40-fold) when PMNs were cocultured with IL-1beta-treated HUVEC. The presence of the protease inhibitor eglin C abolished mitogenic activity generation, suggesting a role for PMN-derived elastase and cathepsin G. Indeed, purified elastase and cathepsin G mimicked PMN-induced mitogen release from HUVEC. Because PMNs firmly adhered to IL-1beta-treated HUVEC, we investigated the role of cell-cell adhesion in mitogen release. Adhesion and PDGF release were inhibited by approximately 60% in the presence of anti-CD11a/CD18 and anti-intercellular adhesion molecule-1 monoclonal antibodies. This study suggests a new role for PMNs and their interaction with endothelium in pathological conditions in which intimal hyperplasia is a common feature. PMID:9763523

Totani, L; Cumashi, A; Piccoli, A; Lorenzet, R

1998-10-01

87

Gene Expression Analysis of TREM1 and GRK2 in Polymorphonuclear Leukocytes as the Surrogate Biomarkers of Acute Bacterial Infections  

PubMed Central

Objective: In the acute stage of infectious diseases such as pneumonia and sepsis, sequelae hypercytokinemia and cytokine storm are often observed simultaneously. During bacterial infections, activated polymorphonuclear leukocytes (PMNs) cause inflammation and organ dysfunction in severely ill patients. Gene expression of the triggering receptor on myeloid cells (TREM)-1 and G-coupled-protein receptor kinase (GRK)-2 in PMNs isolated from patients was analysed to identify genes correlated with the severity of pathophysiological conditions. Methods: mRNA levels of TREM1 and GRK2 in the PMNs from 26 patients (13 with pneumonia, 5 with severe sepsis, and 8 with septic shock) were analysed by using quantitative real-time PCR. The synthesised soluble form (s)TREM-1 was incubated with normal PMNs to investigate its biological functions in vitro. Results: Copies of TREM1 transcript were 0.7- to 2.1-fold higher in patients with pneumonia compared to those of normal subjects; the average fold-change was 1.1-fold. The mRNA levels of patients suffering from severe sepsis and septic shock were 0.34- and 0.33-fold lower compared to those of healthy subjects, respectively. TREM1 mRNA levels in 5 of 26 patients in convalescent stages recovered to normal levels. The mRNA levels of GRK2 in the PMNs of patients were also downregulated. The synthesised sTREM-1 upregulated the mRNA levels of TREM1 in normal PMNs. Conclusions: TREM1 mRNA levels were inversely correlated with the severity of pathophysiological conditions in acute bacterial infections. The gene expression levels of TREM1 in PMNs isolated from patients with bacterial infections may be used as a surrogate biomarker for determining the severity. PMID:24465168

Ubagai, Tsuneyuki; Nakano, Ryuichi; Kikuchi, Hirotoshi; Ono, Yasuo

2014-01-01

88

Differential effect of exogenous interleukin-10 versus glucocorticoids on gene expression and pro-inflammatory cytokine release by polymorphonuclear leukocytes and monocytes of the newly born  

PubMed Central

Bronchopulmonary dysplasia (BPD) is one of the most common causes of mortality and morbidity in neonatal intensive care units. Persistent inflammation, with an abnormal influx of polymorphonuclear leukocytes (PMNs) followed by monocytes (MONOs), occurs early in the pathogenesis of BPD. Anti-inflammatory therapy with better efficacy and safety than dexamethasone (DEX) is needed. In the present study we determined cell-specific gene expression and cytokine release in response to glucocorticoids versus interleukin-10 (IL-10). Subsequently, we hypothesized that the insensitivity of MONOs to DEX was associated with a failure of the glucocorticoid receptor to translocate to the nucleus. PMNs and MONOs were isolated from umbilical cord blood at birth, and pretreated with PBS vehicle, IL-10 or glucocorticoids prior to endotoxin (LPS)-stimulation for 4 and 18h. Genome-wide gene expressions were determined by microarray and validated by RT-qPCR. Interleukin 8 release in cell culture supernatant was measured by ELISA. To examine the mechanism of monocyte insensitivity to glucocorticoids, nuclear translocation of the glucocorticoid receptor was determined by Western blots. MONOs had 6 times the number of genes changing expression with IL-10 compared to PMNs at 4h. DEX at the therapeutic level for neonates with BPD had no effect on gene expression in MONOs. The order of potency for inhibition of interleukin-8 release from MONOs was IL-10 >betamethasone >dexamethasone and hydrocortisone. Glucocorticoid potency in MONOs was directly related to glucocorticoid receptor translocation to nucleus. Gene expression profiling for IL-10 versus glucocorticoids indicates there may be major differences in therapeutic efficacy for BPD. PMID:23390570

Davidson, Dennis; Patel, Hardik; Degoy, Ana C; Gershkovich, Irina; Vancurova, Ivana; Miskolci, Veronika

2013-01-01

89

Differential effect of exogenous interleukin-10 versus glucocorticoids on gene expression and pro-inflammatory cytokine release by polymorphonuclear leukocytes and monocytes of the newly born.  

PubMed

Bronchopulmonary dysplasia (BPD) is one of the most common causes of mortality and morbidity in neonatal intensive care units. Persistent inflammation, with an abnormal influx of polymorphonuclear leukocytes (PMNs) followed by monocytes (MONOs), occurs early in the pathogenesis of BPD. Anti-inflammatory therapy with better efficacy and safety than dexamethasone (DEX) is needed. In the present study we determined cell-specific gene expression and cytokine release in response to glucocorticoids versus interleukin-10 (IL-10). Subsequently, we hypothesized that the insensitivity of MONOs to DEX was associated with a failure of the glucocorticoid receptor to translocate to the nucleus. PMNs and MONOs were isolated from umbilical cord blood at birth, and pretreated with PBS vehicle, IL-10 or glucocorticoids prior to endotoxin (LPS)-stimulation for 4 and 18h. Genome-wide gene expressions were determined by microarray and validated by RT-qPCR. Interleukin 8 release in cell culture supernatant was measured by ELISA. To examine the mechanism of monocyte insensitivity to glucocorticoids, nuclear translocation of the glucocorticoid receptor was determined by Western blots. MONOs had 6 times the number of genes changing expression with IL-10 compared to PMNs at 4h. DEX at the therapeutic level for neonates with BPD had no effect on gene expression in MONOs. The order of potency for inhibition of interleukin-8 release from MONOs was IL-10 >betamethasone >dexamethasone and hydrocortisone. Glucocorticoid potency in MONOs was directly related to glucocorticoid receptor translocation to nucleus. Gene expression profiling for IL-10 versus glucocorticoids indicates there may be major differences in therapeutic efficacy for BPD. PMID:23390570

Davidson, Dennis; Patel, Hardik; Degoy, Ana C; Gershkovich, Irina; Vancurova, Ivana; Miskolci, Veronika

2013-01-01

90

76 FR 5386 - Draft Guidance for Industry: Pre-Storage Leukocyte Reduction of Whole Blood and Blood Components...  

Federal Register 2010, 2011, 2012, 2013

...Industry: Pre-Storage Leukocyte Reduction of Whole Blood and Blood Components Intended for Transfusion; Availability AGENCY...Industry: Pre- Storage Leukocyte Reduction of Whole Blood and Blood Components Intended for Transfusion''...

2011-01-31

91

77 FR 59000 - Guidance for Industry: Pre-Storage Leukocyte Reduction of Whole Blood and Blood Components...  

Federal Register 2010, 2011, 2012, 2013

...Industry: Pre-Storage Leukocyte Reduction of Whole Blood and Blood Components Intended for Transfusion; Availability AGENCY...Industry: Pre- Storage Leukocyte Reduction of Whole Blood and Blood Components Intended for Transfusion''...

2012-09-25

92

Interleukin-10 Versus Dexamethasone: Effects on Polymorphonuclear Leukocyte Functions of the Newborn  

PubMed Central

Interleukin-10 (IL-10), an anti-inflammatory cytokine, may have therapeutic potential in the fetal inflammatory response syndrome and its sequelae such as bronchopulmonary dysplasia (BPD). Our aim was to compare the effects of IL-10 versus dexamethasone (DEX) on important PMN functions of the newborn. PMNs were isolated into culture medium from cord blood after elective cesarean section deliveries. IL-10 and DEX were compared on an equimolar basis corresponding to previously measured plasma levels of DEX from infants treated for BPD. The endotoxin (LPS)-stimulated release of the pro-inflammatory cytokines, tumor necrosis factor (TNF?) and IL-1?, were markedly inhibited equally by IL-10 and DEX; the anti-inflammatory cytokine IL-4 was not released and IL-1 receptor antagonist (IL-1ra) was released less with DEX compared to IL-10. PMNs exposed to LPS, N-formyl-L-methionyl-L-leucyl-L-phenylalanine (fMLP), or S. aureus did not show a significant difference between control, DEX and IL-10 for apoptosis, respiratory burst, phagocytosis or killing respectively. Chemotaxis to fMLP or IL-8 was unaffected by DEX or IL-10. The principal effects of both IL-10 and DEX, on the PMN functions studied, are related to the control of pro- and anti-inflammatory cytokine release. PMID:19127214

Citarella, Brett V; Miskolci, Veronika; Vancurova, Ivana; Davidson, Dennis

2009-01-01

93

Human Cytomegalovirus Replicates Abortively in Polymorphonuclear Leukocytes after Transfer from Infected Endothelial Cells via Transient Microfusion Events  

PubMed Central

Using a recently developed model for in vitro generation of pp65-positive polymorphonuclear leukocytes (PMNLs), we demonstrated that PMNLs from immunocompetent subjects may harbor both infectious human cytomegalovirus (HCMV) and viral products (pp65, p72, DNA, and immediate-early [IE] and pp67 late mRNAs) as early as 60 min after coculture with human umbilical vein endothelial cells (HUVEC) or human embryonic lung fibroblasts (HELF) infected with a clinical HCMV isolate (VR6110) or other wild-type strains. The number of PMNLs positive for each viral parameter increased with coculture time. Using HELF infected with laboratory-adapted HCMV strains, only very small amounts of viral DNA and IE and late mRNAs were detected in PMNLs. A cellular mRNA, the vascular cell adhesion molecule-1 mRNA, which is abundantly present in both infected and uninfected HUVEC, was detected in much larger amounts in PMNLs cocultured with VR6110-infected cells than in controls. Coculture of PMNLs with VR6110-infected permissive cells in the presence or absence of RNA, protein, and viral DNA synthesis inhibitors showed that only IE genes were transcribed in PMNLs during coculture. Synthesis of IE transcripts in PMNLs was also supported by the finding that only the copy number of IE mRNA (and not the DNA or the pp67 mRNA) per infected PMNL increased markedly with time, and the pp67 to IE mRNA copy number ratio changed from greater than 10 in infected HUVEC to less than 1 in cocultured PMNLs. Fluorescent probe transfer experiments and electron microscopy studies indicated that transfer of infectious virus and viral products from infected cells to PMNLs is likely to be mediated by microfusion events induced by wild-type strains only. In addition, HCMV pp65 and p72 were both shown to localize in the nucleus of the same PMNLs by double immunostaining. Two different mechanisms may explain the virus presence in PMNLs: (i) one major mechanism consists of transitory microfusion events (induced by wild-type strains only) of HUVEC or HELF and PMNLs with transfer of viable virus and biologically active viral material to PMNLs; and (ii) one minor mechanism, i.e., endocytosis, occurs with both wild-type and laboratory strains and leads to the acquisition of very small amounts of viral nucleic acids. In conclusion, HCMV replicates abortively in PMNLs, and wild-type strains and their products (as well as cellular metabolites and fluorescent dyes) are transferred to PMNLs, thus providing evidence for a potential mechanism of HCMV dissemination in vivo. PMID:10823870

Gerna, Giuseppe; Percivalle, Elena; Baldanti, Fausto; Sozzani, Silvano; Lanzarini, Paolo; Genini, Emilia; Lilleri, Daniele; Revello, Maria Grazia

2000-01-01

94

Sustained Hypoglycemia Affects Glucose Transporter Expression of Human Blood Leukocytes  

Microsoft Academic Search

ABSTRACTThe scarce data available on leukocyte glucose transporter expression are contradictory and nothing is known about its regulation by glycemic state. Therefore, cytospin preparations of blood leukocytes were searched immunocytochemically for the high-affinity glucose transporters GLUT1, 3, and 4. Hypoglycemia-associated quantitative changes in transporter expression were assessed by flow cytometry. Granulocytes and monocytes stained for GLUT1, 3, and 4. Granulocyte

E. T Korgun; R Demir; P Sedlmayr; G Desoye; G. M Arikan; P Puerstner; M Haeusler; G Dohr; G Skofitsch; T Hahn

2002-01-01

95

Plunder of Human Blood Leukocytes Containing Ingested Material, by Other Leukocytes: Where Is the Fusagen That Allows Preservation of Membrane Integrity and Motile Function?  

PubMed Central

In studying phagocytosis of zymosan particles by human blood monocytes in phase-contrast videomicroscopy, we found that monocytes loaded with zymosan particles became chemotactic for polymorphonuclear leukocytes (PMN) which closed on them and purloined their particle content. This despoliation usually occurred in monocytes that had begun to swell—prefiguring their death. The violent seizure of their contents by the aggressing PMN often tore the monocytes apart. However, some apparently healthy monocyte survived the removal of zymosan content by PMN or, more commonly, its removal by another monocyte. PMN—a much hardier cell in slide preparations—that were similarly loaded with zymosan particles, also attracted PMN. The latter could remove zymosan from the target cell without killing it. Thus, leukocytes were sacrificing significant portions of themselves without losing residual membrane integrity and motile function. Their behavior with respect to other particles (e.g., bacteria) will be of interest. We suggest that the membrane fusagen resides in the inner membrane leaflets when they are brought together in an extreme hourglass configuration. This event may be similar to the fragmentation of erythrocytes into intact pieces, the formation of cytokineplasts, the rear extrusion of content by migrating cells on surfaces, and the phagocytic process itself. PMID:23840370

Malawista, Stephen E.; Chevance de Boisfleury, Anne

2013-01-01

96

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

PubMed

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

Haynes, Johnson; Obiako, Boniface

2002-01-01

97

Cytokine production by leukocytes of Papillon–Lefèvre syndrome patients in whole blood cultures  

Microsoft Academic Search

Papillon–Lefèvre syndrome (PLS) is characterised by aggressively progressive periodontitis combined with palmo-plantar hyperkeratosis.\\u000a It is caused by “loss of function” mutations in the cathepsin C gene. The hypothesis behind this study is that PLS patients’\\u000a polymorphonuclear leukocytes (PMNs) produce more proinflammatory cytokines to compensate for their reduced capacity to neutralize\\u000a leukotoxin and to eliminate Aggregatibacter actinomycetemcomitans. Production of more interleukin

Christian D. Sadik; Barbara Noack; Beate Schacher; Josef Pfeilschifter; Heiko Mühl; Peter Eickholz

98

Myeloid Derived Suppressor Cells (MDSCs) Are Increased and Exert Immunosuppressive Activity Together with Polymorphonuclear Leukocytes (PMNs) in Chronic Myeloid Leukemia Patients  

PubMed Central

Tumor immune tolerance can derive from the recruitment of suppressor cell population, including myeloid derived suppressor cells (MDSCs), able to inhibit T cells activity. We identified a significantly expanded MDSCs population in chronic myeloid leukemia (CML) patients at diagnosis that decreased to normal levels after imatinib therapy. In addition, expression of arginase 1 (Arg1) that depletes microenvironment of arginine, an essential aminoacid for T cell function, resulted in an increase in patients at diagnosis. Purified CML CD11b+CD33+CD14-HLADR- cells markedly suppressed normal donor T cell proliferation in vitro. Comparing CML Gr-MDSCs to autologous polymorphonuclear leukocytes (PMNs) we observed a higher Arg1 expression and activity in PMNs, together with an inhibitory effect on T cells in vitro. Our data indicate that CML cells create an immuno-tolerant environment associated to MDSCs expansion with immunosuppressive capacity mediated by Arg1. In addition, we demonstrated for the first time also an immunosuppressive activity of CML PMNs, suggesting a strong potential immune escape mechanism created by CML cells, which control the anti-tumor reactive T cells. MDSCs should be monitored in imatinib discontinuation trials to understand their importance in relapsing patients. PMID:25014230

Giallongo, Cesarina; Parrinello, Nunziatina; Tibullo, Daniele; La Cava, Piera; Romano, Alessandra; Chiarenza, Annalisa; Barbagallo, Ignazio; Palumbo, Giuseppe A.; Stagno, Fabio; Vigneri, Paolo; Di Raimondo, Francesco

2014-01-01

99

Bacterial phosphatidylcholine-preferring phospholipase C reversibly inhibits the membrane component of the NADPH oxidase in human polymorphonuclear leukocytes: implications for host defense.  

PubMed

Bacterial phosphatidylcholine-preferring phospholipase C (PC-PLC) has been recognized as a virulence factor and is implicated in the hemolytic and dermonecrotic properties associated with certain organisms. Moreover, recent data suggest that PC-PLC may be an important component in the signal transduction cascade by contributing to diacylglycerol (DAG) mass via the hydrolysis of phosphatidylcholine (PC). We have previously shown that PC-PLC can inhibit superoxide generation in human polymorphonuclear leukocytes (PMN). We now extend these observations and show that the mechanism of PC-PLC inhibition of superoxide generation is reversible inhibition of the membrane component of the NADPH oxidase (in a cell-free system) accompanied by expected generation of DAG and phosphorylcholine. Addition of PC reversed the effects of the enzyme. Surprisingly, we also found that phosphatidic acid (PA), the hydrolysis product of phospholipase D, was also produced in intact PMN following PC-PLC exposure. Subsequent addition of the agonist N-formylmethionyl-phenylalanine resulted in further PA production. Restoration of PA in cell-free preparations partially restored superoxide generating capability. We conclude that PC-PLC may enhance bacterial virulence by inhibiting superoxide generation by human PMN, and that this effect is due to direct inhibition of the membrane component of the NADPH oxidase. PMID:8258155

Traynor, A E; Weitzman, S A; Gordon, L I

1993-12-01

100

Influence of polyclonal immunoglobulins on the polymorphonuclear leukocyte response to lipopolysaccharide of Salmonella enteritidis as measured with luminol-enhanced chemiluminescence.  

PubMed Central

In gram-negative sepsis, the activation of polymorphonuclear leukocytes (PMN) by lipopolysaccharide (LPS) and the resulting production of superoxide and other oxygen radicals may be an important cause of tissue damage. A suppression of the PMN response to LPS stimulation would be therapeutically beneficial. The aim of this study was to determine whether different polyclonal immunoglobulins (Igs; 5S-Ig, 7S-Ig, and 19S-Ig) influence the PMN response to LPS of Salmonella enteritidis in vitro. The respiratory burst activity of PMN was measured with luminol-enhanced chemiluminescence. After addition of a 5S-Ig solution containing F(ab')2 fragments of IgG and a 19S-Ig solution containing 12% polyclonal IgM, luminol-enhanced chemiluminescence was reduced by 27% (P < 0.05) and 46% (P < 0.005), respectively. However, after addition of a 7S-Ig solution containing polyclonal IgG, luminol-enhanced chemiluminescence was increased fourfold (P < 0.05). The results suggest that the influence of polyclonal Igs on PMN response to LPS stimulation is dependent on the Ig class, F(ab')2 fragments of IgG and IgM leading to LPS neutralization and IgG leading to the production of potentially toxic oxygen radicals. PMID:7927690

Wagner, D R; Heinrich, D

1994-01-01

101

Myristic Acid, A Side Chain of Phorbol Myristate Acetate (PMA), Can Activate Human Polymorphonuclear Leukocytes to Produce Oxygen Radicals More Potently than PMA  

PubMed Central

Myristic acid (MyA), which is a saturated fatty acid (C14:0) and a side chain of phorbol 12-myristate 13-acetate (PMA), was examined if MyA stimulates human polymorphonuclear leukocytes (PMNs) to release oxygen radicals comparable to PMA by applying electron paramagnetic resonance (EPR)-spin-trapping method. When MyA was added to isolated human PMNs, spin adducts of 5,5-dimethyl-1-pyrroline-N-oxide (DMPO)-OH and DMPO-OOH were time-dependently observed. The amounts of these spin adducts were larger than those of PMNs stimulated by PMA. These results clearly show that MyA is more potent agent to prime human PMNs than PMA, in a point of view of not only O2·? but also ·OH production. This fact calls attention that too much intake of MyA that is known to be contained vegetable oils can lead to crippling effect through uncontrolled production of reactive oxygen species. PMID:19902021

Tada, Mika; Ichiishi, Eiichiro; Saito, Rumiko; Emoto, Natsumi; Niwano, Yoshimi; Kohno, Masahiro

2009-01-01

102

Randomized trial comparing packed red cell blood transfusion with and without leukocyte depletion for gastrointestinal surgery  

Microsoft Academic Search

BACKGROUND: Allogeneic transfusion is associated with postoperative infections that significantly prolong hospital stays and increase costs. Recent studies suggest that filtering leukocytes from blood prior to transfusion reduces the risk of postoperative infection associated with blood transfusion. We compared the incidence of postoperative infections, hospital stays, and hospital charges of gastrointestinal surgery patients transfused with packed red cells or leukocyte-depleted

Paul Ian Tartter; Kala Mohandas; Penny Azar; Jill Endres; Jess Kaplan; Morton Spivack

1998-01-01

103

Maintenance of ?1-antitrypsin activity by means of co-application of hypochlorous acid-scavengers in vitro and in the supernatant of polymorphonuclear leukocytes  

PubMed Central

Tissue destruction, pain and loss of function in chronically inflamed tissues can result from noxious agents released from myeloperoxidase (MPO) and its highly reactive product hypochlorous acid (HOCl) or proteases such as neutrophil elastase (NE). Currently there exists a high demand for medications that provide gentle treatments, free from side effects inherent in those prescribed today. One method to circumvent side effects is through the use of locally applied drug delivery. In contrast to systemic therapy, the main advantages of transport systems are the low dosages of drug with a time-controlled delivery. The aim of this study was to ascertain interactions of NE and its inhibitor ?1-antitrypsin (AT), the influence of hypochlorous acid (HOCl), as well as its scavengers, in order to define an effective mixture of drugs acting in a synergistic way which can be applied by means of drug delivery systems. These investigations determine the effective amounts of AT/HOCl-scavengers that drug mixtures need for delivery under inflammatory conditions in order to prevent tissue damage. AT was shown to inhibit NE in a dose-dependent manner, whereas a physiological concentration of 1.14 µM AT caused a significant NE inhibition (78%, pH 7.5). The concomitant existence of MPO/HOCl inactivated AT in a dose-dependent manner as well. To regain AT efficacy, HOCl-scavengers, such as l-methionine, ?-aminosalicylic acid and cefoperazone were additionally applied. Finally, AT was assembled as surface layer onto layer-by-layer biopolymer-coated microcarriers and carrier phagocytosis by polymorphonuclear leukocytes could be shown. PMID:23507783

Schönberg, Maria; Reibetanz, Uta; Rathmann, Sophie; Leßig, Jacqueline

2012-01-01

104

Differential expression of interleukin-8 by polymorphonuclear leukocytes of two closely related species, Ovis canadensis and Ovis aries, in response to Mannheimia haemolytica infection.  

PubMed

The pneumonic lesions and mortality caused by Mannheimia haemolytica in bighorn sheep (BHS; Ovis canadensis) are more severe than those in the related species, domestic sheep (DS; Ovis aries), under both natural and experimental conditions. Leukotoxin (Lkt) and lipopolysaccharide (LPS) are the most important virulence factors of this organism. One hallmark of pathogenesis of pneumonia is the influx of polymorphonuclear leukocytes (PMNs) into the lungs. Lkt-induced cytolysis of PMNs results in the release of cytotoxic compounds capable of damaging lung tissue. Interleukin-8 (IL-8) is a potent PMN chemoattractant. The objective of the present study was to determine if there is differential expression of IL-8 by the macrophages and PMNs of BHS and DS in response to M. haemolytica. Macrophages and PMNs of BHS and DS were stimulated with heat-killed M. haemolytica or LPS. IL-8 expression by the cells was measured by enzyme-linked immunosorbent assays and real-time reverse transcription-PCR (RT-PCR). The PMNs of BHS expressed severalfold higher levels of IL-8 than those of DS upon stimulation. Lesional lung tissue of M. haemolytica-infected BHS contained significantly higher levels of IL-8 than nonlesional tissue. The bronchoalveolar lavage (BAL) fluid of infected BHS also contained higher levels of IL-8 than that of infected DS. Depletion of IL-8 reduced migration of PMNs toward BAL fluid by approximately 50%, indicating that IL-8 is integral to PMN recruitment to the lung during M. haemolytica infection. Excessive production of IL-8, enhanced recruitment of PMNs, and PMN lysis by Lkt are likely responsible for the severity of the lung lesions in M. haemolytica-infected BHS. PMID:20515932

Herndon, Caroline N; Foreyt, William J; Srikumaran, Subramaniam

2010-08-01

105

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

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

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

106

?3/4 Fucosyltransferase 3-dependent synthesis of Sialyl Lewis A on CD44 variant containing exon 6 mediates polymorphonuclear leukocyte detachment from intestinal epithelium during transepithelial migration.  

PubMed

Polymorphonuclear leukocyte (PMN) migration across the intestinal epithelium closely parallels disease symptoms in patients with inflammatory bowel disease. PMN transepithelial migration (TEM) is a multistep process that terminates with PMN detachment from the apical epithelium into the lumen. Using a unique mAb (GM35), we have previously demonstrated that engagement of the CD44 variant containing exon 6 (CD44v6) blocks both PMN detachment and cleavage of CD44v6. In this article, we report that PMN binding to CD44v6 is mediated by protein-specific O-glycosylation with sialyl Lewis A (sLe(a)). Analyses of glycosyltransferase expression identified fucosyltransferase 3 (Fut3) as the key enzyme driving sLe(a) biosynthesis in human intestinal epithelial cells (IECs). Fut3 transfection of sLe(a)-deficient IECs resulted in robust expression of sLe(a). However, this glycan was not expressed on CD44v6 in these transfected IECs; therefore, engagement of sLe(a) had no effect on PMN TEM across these cells. Analyses of sLe(a) in human colonic mucosa revealed minimal expression in noninflamed areas, with striking upregulation under colitic conditions that correlated with increased expression of CD44v6. Importantly, intraluminal administration of mAb GM35 blocked PMN TEM and attenuated associated increases in intestinal permeability in a murine intestinal model of inflammation. These findings identify a unique role for protein-specific O-glycosylation in regulating PMN-epithelial interactions at the luminal surface of the intestine. PMID:24068663

Brazil, Jennifer C; Liu, Renpeng; Sumagin, Ronen; Kolegraff, Keli N; Nusrat, Asma; Cummings, Richard D; Parkos, Charles A; Louis, Nancy A

2013-11-01

107

Continuous infusion of Escherichia coli endotoxin in vivo primes in vitro superoxide anion release in rat polymorphonuclear leukocytes and Kupffer cells in a time-dependent manner.  

PubMed Central

Continuous infusion of a nonlethal dose of Escherichia coli lipopolysaccharide (LPS) (0.5 mg/kg) induced early (3 h) accumulation of polymorphonuclear leukocytes (PMNL) in rat liver followed by later (30 h) greater extravasation of mononuclear phagocytes (MNP) (E. B. Rodriguez de Turco and J. A. Spitzer, J. Leukocyte Biol. 48:488-494, 1990). Nonparenchymal liver cells from rats treated for 3 and 30 h with LPS were recovered by centrifugal elutriation, yielding a 23-ml/min fraction (endothelial cells) and a 45-ml/min fraction (PMNL, Kupffer cells, and MNP), and compared for their capacity for basal and agonist-stimulated superoxide (O2-) production. Stimulation with phorbol myristate acetate and opsonized zymosan caused a dose-dependent release of O2- from the 45-ml/min fraction derived from rats treated for 3 h with saline, but not from the 23-ml/min fraction. Further purification of the 45-ml/min fraction by discontinuous density gradient centrifugation into a Kupffer and a PMNL fraction revealed that most of the agonist-induced O2- release was generated by infiltrating PMNL at this early time point of LPS infusion. By 30 h of LPS infusion, although enhancement of the phorbol-12-myristate-13-acetate- and opsonized zymosan-stimulated release of O2- was observed in the 45-ml/min fraction, but not in the 23-ml/min fraction, the maximum release of O2- was smaller than that observed in the rats treated for 3 h. Our results support the following conclusions: (i) after a 3-h LPS infusion, PMNL found in the liver in increased numbers are also highly primed for agonist-stimulated release of O2-, while Kupffer cell priming is of a lesser extent; (ii) after a 30-h infusion of LPS, infiltrating MNP found in the liver in increased numbers are primed for agonist-induced O2- release, while priming of PMNL has diminished; (iii) at both 3 and 30 h of LPS infusion, liver endothelial cells are not significantly primed for agonist-stimulated O2- release; and (iv) in vivo priming by LPS infusion at both 3 and 30 h was not reversed by the experimental method used for cell recovery (ca. 3 h), thus suggesting that in vivo LPS priming of O2- release may ultimately lead to severe impairment of liver function and metabolism observed during endotoxemia and sepsis if not therapeutically blocked at an early time point. PMID:1657786

Mayer, A M; Spitzer, J A

1991-01-01

108

The ontogeny of a 57-Kd cationic antimicrobial protein of human polymorphonuclear leukocytes: localization to a novel granule population.  

PubMed

The ontogeny of a 57-Kd cationic antimicrobial protein (CAP57) that has substantial similarities to bactericidal permeability increasing protein (BPI) has been determined immunocytochemically. CAP57 was detected in the granules of mature peripheral blood neutrophils. However, it was absent from other cells of the peripheral blood: eosinophils, red blood cells (RBCs), and mononuclear cells. In human bone marrow, CAP57 was confined to the neutrophilic series. The earliest stage of development of the myeloid cells at which CAP57 was demonstrated was the promyelocyte. Double immunofluorescent labeling showed that CAP57 was detected in cells positive for myeloperoxidase. The absence of lactoferrin in certain cells (promyelocytes) containing CAP57 indicated that CAP57 was synthesized and packaged in a population of granules prior to the development of granules that contain lactoferrin. CAP57 could not be demonstrated in HL60 cells either by enzyme-linked immunosorbent assay (ELISA) or by immunocytochemistry. However, the presence of another granule-associated cationic antimicrobial protein of molecular weight 37 Kd (CAP37) was readily detected in undifferentiated HL60 cells. Amino acid sequence analysis showed that CAP57 and BPI were identical. Further indication of the identity between CAP57 and BPI was that monoclonal anti-CAP57 antibodies cross reacted with BPI. Sucrose density-gradient centrifugations showed CAP57 was confined to a granule population that exhibited a buoyant density intermediate of the previously described light and heavy azurophil granules. Further resolution of the individual azurophil granule populations by Percoll density-gradient centrifugation revealed that CAP57 was most concentrated in the density range of 1.093 to 1.100 g/cc. These results strongly suggest the unique finding that CAP57 may be associated with a heretofore unreported granule type. PMID:2200540

Pereira, H A; Spitznagel, J K; Winton, E F; Shafer, W M; Martin, L E; Guzman, G S; Pohl, J; Scott, R W; Marra, M N; Kinkade, J M

1990-08-15

109

Evaluation of antitularaemia immunity via whole human blood leukocyte cytofluorometric analysis  

NASA Astrophysics Data System (ADS)

Tularaemia is followed by development of a long-lasting protective immunity. Peripheral blood leukocytes of vaccinated individuals partially lysed in vitro after exposure to killed Francisella tularensis cells and this leukocytolis reaction is used for evaluation of antitularaemia immunity. Here, results from cytofluorometric characterization of human whole blood leukocyte response following exposure to F. tularensis are reported. Leukocytes were stained in whole blood by acridine orange. The green (nuclear chromatin) and red (lysosomal granules) fluorescent signals from individual cells were measured by flow cytometry to detect the decrease of leukocyte concentration in whole human blood (the leukocytolis intensity) and to calculate the damaged leukocytes with changed chromatin structure and lysosomal granules per cell content. Our data indicate that flow cytometry offers a rapid and more informative technique for evaluation of human antitularaemia immunity in vitro.

Firstova, Victoria V.; Kravtsov, Alexander L.; Schmelkova, Tatyana P.; Shchukovskaya, Tatyana N.

2005-06-01

110

Variation in sister chromatid exchange frequencies between human and pig whole blood, plasma leukocyte, and mononuclear leukocyte cultures  

Microsoft Academic Search

Sister chromatid exchange (SCE) induction by ultraviolet (UV) light was studied in both human and pig whole blood cultures (WBC) and plasma leukocyte cultures (PLC). No variation in SCE frequency was observed between pig WBC and PLC in control as well as in treated cells. Conversely, SCE frequencies of human PLC were consistently higher than those of WBC in control

Marcelo L. Larramendy; Miguel A. Reigosa

1986-01-01

111

Seasonal variation of peripheral blood leukocyte telomere length in Costa Rica: a population based observational study  

PubMed Central

Objectives Peripheral blood leukocyte telomere length is increasingly being used as a biomarker of aging, but its natural variation in human populations is not well understood. Several other biomarkers show seasonal variation, as do several determinants of leukocyte telomere length. We examined whether there was monthly variation in leukocyte telomere length in Costa Rica, a country with strong seasonal differences in precipitation and infection. Methods We examined a longitudinal population based cohort of 581 Costa Rican adults age 60 and above, from which blood samples were drawn between October 2006 and July 2008. Leukocyte telomere length was assayed from these samples using the quantitative PCR method. Multivariate regression models were used to examine correlations between month of blood draw and leukocyte telomere length. Results Telomere length from peripheral blood leukocytes varied by as much as 200 base pairs depending on month of blood draw, and this difference is not likely to be due to random variation. A moderate proportion of this association is statistically accounted for by month and region specific average rainfall. We found shorter telomere length associated with greater rainfall. Conclusions There are two possible explanations of our findings. First, there could be relatively rapid month-to-month changes in leukocyte telomere length. This conclusion would have implications for understanding the natural population dynamics of telomere length. Second, there could be seasonal differences in constituent cell populations. This conclusion would suggest that future studies of leukocyte telomere length use methods to account for the potential impact of constituent cell type. PMID:24615938

Rehkopf, David H; Dow, William H; Rosero-Bixby, Luis; Lin, Jue; Epel, Elissa S; Blackburn, Elizabeth H

2014-01-01

112

Human leukocyte elastase is an endogenous ligand for the integrin CR3 (CD11b/CD18, Mac-1, alpha M beta 2) and modulates polymorphonuclear leukocyte adhesion  

PubMed Central

Integrin CR3 (CD11b/CD18, Mac-1, alpha M beta 2) mediates the transient adhesion of polymorphonuclear leukocytes (PMN) to surfaces coated with fibrinogen, C3bi, ICAM-1, and other ligands. Recent studies (Cai, T.- Q., and S.D. Wright 1995. J. Biol. Chem. 270:14358) suggest that adhesion may be favored by stimulus-dependent changes in the kinetics of ligand binding by CR3. Cell detachment, on the other hand, must occur by a different mechanism because binding kinetics cannot affect cell adhesion after binding of ligand has occurred. We have sought a mechanism that would reverse binding of ligand to CR3 and report here that lysates of PMN contain an endogenous ligand that binds CR3 and competes the binding of C3bi. Purification and sequence analysis identified the structurally homologous azurophilic granule proteins, elastase, protease 3, and azurocidin as candidates. Studies with purified elastase and azurocidin showed that each bound specifically to purified, immobilized CR3. Elastase may play a role in modulating integrin-mediated cell adhesion because it is expressed at the cell surface, and the expression level is inversely proportional to cell adhesivity. Furthermore, a monoclonal antibody against elastase prevented detachment of PMN from fibrinogen-coated surfaces and blocked chemotaxis, confirming a role for this protein in regulating integrin- mediated adhesion. These studies suggest a model for release of integrin-mediated cell adhesion in which endogenous ligands such as elastase may release adhesion by "'eluting" substrate-bound ligand. A role for the proteolytic activity of elastase appears likely but is not demonstrated in this study. PMID:8879192

1996-01-01

113

DNA damage in peripheral blood leukocytes in tobacco users  

PubMed Central

Aim: To Quantify the DNA single-stranded breaks in the peripheral blood leukocytes (PBLs) of tobacco-habituated individuals with clinically normal mucosa and patients with oral carcinoma. Objectives: To evaluate DNA damage levels in PBLs of tobacco-habituated individuals with clinically normal mucosa and patients with oral carcinoma and compare with a control group of healthy volunteers. To evaluate the extent of DNA damage in PBLs using Single Cell Gel Electrophoresis (SCGE) in the above groups. Materials and Methods: Patients who were attending the outpatient department were enrolled in this study. A control group of 30 healthy volunteers included in Group I were selected from various age groups who are not tobacco users in any form. Thirty patients with tobacco habituation but with clinically normal mucosa were included in Group II, while 30 tobacco-habituated patients with oral squamous carcinoma were included in Group III. A biopsy was taken from the representative area and confirmed histologically. Intravenous blood samples were collected from all the groups for evaluation of the extent of DNA damage using ethidium bromide-stained slides under fluorescent microscope. The DNA tail length was calculated by subtracting the diameter from the total length. Twenty-five randomly selected cells per slide were analyzed and mean calculated. Results: The mean DNA damage levels in patients with tobacco habits were compared with that of the control group and the results were found to be statistically significant. The mean DNA damage level in PBLs between tobacco-habituated patients with normal mucosa and oral cancer patients was found to be statistically significant. The DNA damage in cancer patients was compared with the control group and the results were found to be statistically significant. Conclusion: DNA damage evaluation in PBLs by SCGE technique is a sensitive and reliable indicator of tobacco insult. PMID:25364170

Guttikonda, Venkateswara Rao; Patil, Rekha; Kumar, GS

2014-01-01

114

Leukocytes are primed in peripheral blood for activation during term and preterm labour†  

PubMed Central

We hypothesized that the priming and activation of maternal leukocytes in peripheral blood is a key component of parturition, and that inappropriate preterm priming of leukocytes might initiate preterm labour and delivery. The purpose of this study was to characterize peripheral blood leukocyte activation during human term and preterm labour. We obtained blood samples from pregnant women at term and preterm, both in labour and not in labour. Leukocytes were characterized according to cell subtype and cell surface marker expression. Additionally, we quantified leukocyte cytokine mRNA production, migratory ability and reactive oxygen species production of neutrophils and macrophages. We found that both term and preterm labour were associated with an increase in monocyte and neutrophil proportion or number—neutrophil migratory ability and cell surface marker expression indicating activation. Messenger RNA expression of IL-1? and IL-8, MCP-1 and TLR-2 was also increased. We conclude that leukocytes in peripheral blood are primed in preparation for activation during term and preterm labour, and that this may contribute to the pathophysiological events of parturition. These data may lead to novel therapies and diagnostic tools for the prevention and/or diagnosis of preterm birth. PMID:19628509

Yuan, M.; Jordan, F.; McInnes, I.B.; Harnett, M.M.; Norman, J.E.

2009-01-01

115

Microfluidic aqueous two phase system for leukocyte concentration from whole blood.  

PubMed

Leukocytes from a whole blood sample were concentrated using a microfluidic aqueous two phase system (microATPS). Whole blood was simultaneously exposed to polyethylene glycol (PEG) and dextran (Dex) phase streams and cells were partitioned based on their differential affinity for the streams. The laminar flow characteristic of microfluidic devices was used to create zero, one, and two stable interfaces between the polymer streams. Three different patterns of three polymer streams each were evaluated for their effectiveness in concentrating leukocytes: immiscible PEG-PEG-Dex, immiscible Dex-PEG-Dex, and miscible PEG-PBS-Dex. The most effective configuration was the Dex-PEG-Dex stream pattern which on average increased the ratio of leukocytes to erythrocytes by a factor of 9.13 over unconcentrated blood. PMID:18937070

Soohoo, Jeffrey R; Walker, Glenn M

2009-04-01

116

Blood bank leukocyte infusions as remission induction therapy in a case of acute lymphoblastic leukemia.  

PubMed

A 15-year-old female with pre-pre B ALL in third relapse was treated with administration of eight blood bank leukocyte concentrates per day for 5 days. The total number of mononuclear cells per kilogram of weight was 4.89 x 10(8). On the fifth day of infusions the patient was in complete remission (CR), asymptomatic and with a normal CBC. No secondary effects were found. The patient remained in CR without treatment for 10 weeks before relapsing again. The possibility of reaching a short-lived, clinically relevant response, using blood bank leukocyte infusions, is a promising new approach for the treatment of leukemia. PMID:9383238

Borbolla, J R; López, M A; Alvarado, M; Guzman, L; DeDiego, J; Trueba, E; González, M; Anaya, I

1997-10-01

117

Differential leukocyte counting and immunophenotyping in cryopreserved ex vivo whole blood.  

PubMed

Absolute cell counts are typically measured in fresh samples, but this is impractical in large field studies. We compared quantification of leukocyte proportions and absolute counts using reference real-time methods (stain and lyse/no-wash (LNW) or hematology analyser) with a novel assay that allows long-term cryopreservation of fixed leukocytes for later counting (DLC-ICE: differential leukocyte count and immunophenotype in cryopreserved ex vivo whole blood). For the LNW method, whole blood (WB) was stained with fluorescent antibodies, then erythrocytes were lysed, and leukocytes fixed prior to flow cytometry. Alternatively, our novel DLC-ICE method entailed erythrocyte lysis and leukocyte fixation, cryopreservation and later staining of permeabilized cells prior to flow cytometry. Outcomes were proportions and absolute counts of granulocytes, lymphocytes, monocytes, T cells, B cells, and activated T cells within the leukocyte population. We also compared leukocyte subset counts in fresh WB from 51 healthy infants measured by hematology analyser at a rural clinical site or by DLC-ICE method after 2 years of cryopreservation. We observed excellent agreement and strong correlations between absolute counts or cell proportions measured by the LNW and DLC-ICE methods on fresh WB from 10 healthy adults. Compared to LNW, DLC-ICE yielded similar or brighter staining even after cryopreservation. Duration of cryopreservation, assessed monthly for 1 year, had little effect on cell enumeration: median coefficients of variation were below 15% for all outcomes. Under field site conditions, we observed strong correlations between infant leukocyte numbers measured in fresh samples by hematology analyser and those measured by DLC-ICE up to 2 years of cryopreservation. Our novel DLC-ICE method allows accurate flow cytometric quantification of cell subsets from fixed WB even after long-term cryopreservation. This method is ideal for batched, retrospective analysis of samples from large field studies, or when advanced flow cytometry equipment is not available for clinical research purposes. © 2014 International Society for Advancement of Cytometry. PMID:25515205

Nemes, Elisa; Kagina, Benjamin M N; Smit, Erica; Africa, Hadn; Steyn, Marcia; Hanekom, Willem A; Scriba, Thomas J

2015-02-01

118

Selection of the best features for leukocytes classification in blood smear microscopic images  

NASA Astrophysics Data System (ADS)

Automatic differential counting of leukocytes provides invaluable information to pathologist for diagnosis and treatment of many diseases. The main objective of this paper is to detect leukocytes from a blood smear microscopic image and classify them into their types: Neutrophil, Eosinophil, Basophil, Lymphocyte and Monocyte using features that pathologists consider to differentiate leukocytes. Features contain color, geometric and texture features. Colors of nucleus and cytoplasm vary among the leukocytes. Lymphocytes have single, large, round or oval and Monocytes have singular convoluted shape nucleus. Nucleus of Eosinophils is divided into 2 segments and nucleus of Neutrophils into 2 to 5 segments. Lymphocytes often have no granules, Monocytes have tiny granules, Neutrophils have fine granules and Eosinophils have large granules in cytoplasm. Six color features is extracted from both nucleus and cytoplasm, 6 geometric features only from nucleus and 6 statistical features and 7 moment invariants features only from cytoplasm of leukocytes. These features are fed to support vector machine (SVM) classifiers with one to one architecture. The results obtained by applying the proposed method on blood smear microscopic image of 10 patients including 149 white blood cells (WBCs) indicate that correct rate for all classifiers are above 93% which is in a higher level in comparison with previous literatures.

Sarrafzadeh, Omid; Rabbani, Hossein; Talebi, Ardeshir; Banaem, Hossein Usefi

2014-03-01

119

Comparative glycomics of leukocyte glycosaminoglycans.  

PubMed

Glycosaminoglycans (GAGs) vary widely in disaccharide and oligosaccharide content in a tissue-specific manner. Nonetheless, there are common structural features, such as the presence of highly sulfated non-reducing end domains on heparan sulfate (HS) chains. Less clear are the patterns of expression of GAGs on specific cell types. Leukocytes are known to express GAGs primarily of the chondroitin sulfate (CS) type. However, little is known regarding the properties and structures of the GAG chains, their variability among normal subjects, and changes in structure associated with disease conditions. We isolated peripheral blood leukocyte populations from four human donors and extracted GAGs. We determined the relative and absolute disaccharide abundances for HS and CS GAGs classes using size exclusion chromatography-mass spectrometry (SEC-MS). We found that all leukocytes express HS chains with a level of sulfation that is more similar to heparin than to organ-derived HS. The levels of HS expression follows the trend T cells/B cells > monocytes/natural killer cells > polymorphonuclear leukocytes (PMNs). In addition, CS abundances were considerably higher than total HS but varied considerably in a leukocyte cell type-specific manner. Levels of CS were higher for myeloid lineage cells (PMNs and monocytes) than for lymphoid cells (B, T and natural killer (NK) cells). This information establishes the range of GAG structures expressed on normal leukocytes and is necessary for subsequent inquiry into disease conditions. PMID:23480678

Shao, Chun; Shi, Xiaofeng; White, Mitchell; Huang, Yu; Hartshorn, Kevan; Zaia, Joseph

2013-05-01

120

Modulation of Adhesion Molecule Profiles on Alveolar Macrophages and Blood Leukocytes  

Microsoft Academic Search

Background: Cell adhesion molecules are believed to be essential for blood cell recruitment to the lung and for the movement of alveolar macrophages (AM) within the lung. Objective: To investigate the expression pattern of L-selectin and ?2 integrins on blood leukocytes and AM, including AM of various maturity. Methods: Flow cytometry was used to study the expression of L-selectin (CD62L)

T. S. Haugen; O. H. Skjønsberg; B. Nakstad; T. Lyberg

1999-01-01

121

DIFFERENCES IN ENZYME CONTENT OF AZUROPHIL AND SPECIFIC GRANULES OF POLYMORPHONUCLEAR LEUKOCYTES: II. Cytochemistry and Electron Microscopy of Bone Marrow Cells  

Microsoft Academic Search

In the previous paper we presented findings which indicated that enzyme heterogeneity exists among PMN leukocyte granules. From histochemical staining of bone marrow smears, we obtained evidence that azurophil and specific granules differ in their enzyme content. Moreover, a given enzyme appeared to be restricted to one of the two types. Clear results were obtained with alkaline phosphatase, but those

D. F. Bainton; MARILYN G. FARQUHAR

1968-01-01

122

Altered expression of adhesion molecules on peripheral blood leukocytes in feline infectious peritonitis.  

PubMed

Feline infectious peritonitis (FIP) is a fatal, coronavirus-induced systemic disease in domestic and wild felids. The pathology associated with FIP (multifocal granulomatous vasculitis) is considered to be elicited by exaggerated activation and subsequent extravasation of leukocytes. As changes in the expression of adhesion molecules on circulating leukocytes precede their margination and emigration, we reasoned that the expression of leukocyte adhesion molecules may be altered in FIP. In present study, the expression of principal adhesion molecules involved in leukocyte transmigration (CD15s, CD11a, CD11b, CD18, CD49d, and CD54) on peripheral blood leukocytes from cats with naturally occurring FIP (n=15) and controls (n=12) was quantified by flow cytometry using a formaldehyde-based rapid leukocyte preparation technique. T- and B-lymphocytes from FIP patients exhibit higher expression of both subunits (CD11a and CD18) composing the ?2 integrin lymphocyte function-associated antigen (LFA)-1. In addition, the expression of the ?4 subunit (CD49d) of the ?1 integrin very late antigen (VLA)-4 was elevated on B-lymphocytes from FIP patients. The expression of CD11b and CD18, that combine to form the ?2 integrin macrophage-1 antigen (Mac-1), was elevated on monocytes, whereas the density of CD49d was reduced on this population in FIP. Granulocytes of FIP cats displayed an increased expression of the ? chain of Mac-1 (CD11b). These observations suggest that leukocytes from FIP patients show signs of systemic activation causing them to extravasate into surrounding tissues and ultimately contribute to pyogranuloma formation seen in FIP. PMID:23910523

Olyslaegers, Dominique A J; Dedeurwaerder, Annelike; Desmarets, Lowiese M B; Vermeulen, Ben L; Dewerchin, Hannah L; Nauwynck, Hans J

2013-10-25

123

Forces on a Wall-Bound Leukocyte in a Small Vessel Due to Red Cells in the Blood Stream  

E-print Network

Forces on a Wall-Bound Leukocyte in a Small Vessel Due to Red Cells in the Blood Stream Amir H. G at Urbana-Champaign, Urbana, Illinois ABSTRACT As part of the inflammation response, white blood cells character of blood, especially in small vessels where the red blood cells must substantially deform to pass

Freund, Jonathan B.

124

Leukocyte recovery from umbilical cord blood by poligeline  

Microsoft Academic Search

Umbilical cord blood (UCB) collected at delivery is a source of transplantable stem\\/progenitor cells; it represents an alternative to bone marrow to restore hematopoiesis in patients affected by malignant and non-malignant disease. Therefore, large-scale UCB banks would be a natural complement to bone marrow donor registries. Storage of unmanipulated whole UCB units requires a great number of liquid nitrogen containers.

P. Perutelli; S. Catellani

1999-01-01

125

Evidence for overdispersion in the distribution of malaria parasites and leukocytes in thick blood smears  

PubMed Central

Background Microscopic examination of stained thick blood smears (TBS) is the gold standard for routine malaria diagnosis. Parasites and leukocytes are counted in a predetermined number of high power fields (HPFs). Data on parasite and leukocyte counts per HPF are of broad scientific value. However, in published studies, most of the information on parasite density (PD) is presented as summary statistics (e.g. PD per microlitre, prevalence, absolute/assumed white blood cell counts), but original data sets are not readily available. Besides, the number of parasites and the number of leukocytes per HPF are assumed to be Poisson-distributed. However, count data rarely fit the restrictive assumptions of the Poisson distribution. The violation of these assumptions commonly results in overdispersion. The objectives of this paper are to investigate and handle overdispersion in field-collected data. Methods The data comprise the records of three TBSs of 12-month-old children from a field study of Plasmodium falciparum malaria in Tori Bossito, Benin. All HPFs were examined systemically by visually scanning the film horizontally from edge to edge. The numbers of parasites and leukocytes per HPF were recorded and formed the first dataset on parasite and leukocyte counts per HPF. The full dataset is published in this study. Two sources of overdispersion in data are investigated: latent heterogeneity and spatial dependence. Unobserved heterogeneity in data is accounted for by considering more flexible models that allow for overdispersion. Of particular interest were the negative binomial model (NB) and mixture models. The dependent structure in data was modelled with hidden Markov models (HMMs). Results The Poisson assumptions are inconsistent with parasite and leukocyte distributions per HPF. Among simple parametric models, the NB model is the closest to the unknown distribution that generates the data. On the basis of model selection criteria AIC and BIC, HMMs provided a better fit to data than mixtures. Ordinary pseudo-residuals confirmed the validity of HMMs. Conclusion Failure to take overdispersion into account in parasite and leukocyte counts may entail important misleading inferences when these data are related to other explanatory variables (malariometric or environmental). Its detection is therefore essential. In addition, an alternative PD estimation method that accounts for heterogeneity and spatial dependence should be seriously considered in epidemiological studies with field-collected parasite and leukocyte data. PMID:24195469

2013-01-01

126

In vitro evaluation of feline leukocytes radiolabeled in whole blood with 99mTc stannous colloid.  

PubMed

Technetium-99m stannous colloid (9mTcSnC) has been used to radiolabel human leukocytes to investigate various inflammatory disorders. We investigated the in vitro behavior of feline leukocytes labeled in whole blood with 99mTcSnC. Heparinized blood samples were collected from healthy cats and divided into control and test aliquots. The latter were labeled with 99mTcSnC using a standard procedure. Leukocyte viability was determined for each sample using a trypan blue exclusion test. Labeling efficiency was determined for test aliquots. Test aliquots were layered onto Histopaque-1077 and centrifuged before measurement of radioactivity of the blood components. Leukocytes from radiolabeled and control samples were washed and incubated with opsonized zymosan particles to allow assessment of phagocytic function. Aliquots were taken from radiolabeled feline leukocyte samples at 1, 3, 4, and 7 h postlabelling. After centrifugation of each aliquot, radioactivity of the supernatant and pellet was measured and the labeling retention determined. Leukocyte viability in both radiolabeled and control samples was > 98%. The labeling efficiency was 95.2 +/- 0.14%. The distribution of radioactivity in feline blood was found to be 3.4 +/- 0.18% in plasma, 39.0 +/- 0.37% in erythrocytes, and 57.6 +/- 0.38% in leukocytes. Labeled feline leukocytes had phagocytic activity of 90.9 +/- 0.18% (control 91.3 +/- 0.15%). The radiolabeled leukocytes retained 93.4 +/- 0.19% of the radioactivity up to 7h postlabeling. 99TcSnC efficiently labeled feline leukocytes with no effect on viability and minimal effect on phagocytic function. The percentage retention of radioactivity by the leukocytes was still high at 7h postlabeling. PMID:19788042

Abushhiwa, Mohamed H; Salehi, Nouria S; Whitton, Robert C; Charles, Jennifer A; Finnin, Peter J; Lording, Peter M; Parry, Bruce W

2009-01-01

127

Selection against mutant alleles in blood leukocytes is a consistent feature in Incontinentia Pigmenti type 2  

Microsoft Academic Search

Incontinentia Pigmenti 2 (IP2) is an X-linked dominant disorder with male lethality. Affected females display a characteristic skin eruption that evolves through four classic stages, frequently accompanied by dental and retinal abnormalities. Non-random (skewed) X-inactivation in peripheral blood leukocytes and in fibroblasts has been observed in females with IP2; however, sample sizes have been small and methods of analysis varied.

Julia E. Parrish; Angela E. Scheuerle; Richard A. Lewis; Moise L. Levy; David L. Nelson

1996-01-01

128

Observations on the technique for the study of human chromosomes by the culture of leukocytes from peripheral blood.  

PubMed

A critical analysis of the various features of blood leukocyte culture for the study of human chromosomes was carried out. The following observations were made: (1) Fasting blood was essential for effective separation of leukocytes. (2) These cells are easily obtained by differential centrifugation and RBC sedimentation. (3) Non-specific agglutination of leukocytes was prevented by the use of Eagle's medium for suspension cultures. (4) No contamination occurred in a series of 50 leukocyte cultures to which antibiotics were not added. (5) Addition of an experimental Phaseolus vulgaris extract at concentration of 1 x 10(-4) to cultures resulted in a 12 to 15% mitotic index. (6) Desacetyl-methyl-colchicine (Colcemid) had optimal effect at concentration of 0.1 mug./ml. (7) Distilled water added to cell suspension in culture medium (5: 1) was an effective hypotonic agent.A simplified technique of leukocyte culture for chromosome preparations is proposed. PMID:13947140

GENEST, P; AUGER, C

1963-02-01

129

Shorter telomere length in peripheral blood leukocytes is associated with childhood autism.  

PubMed

Telomeres are protective chromosomal structures that play a key role in preserving genomic stability. Epidemiologic studies have shown that the abnormal telomere length in leukocytes is associated with some mental disorders and age-related diseases. However, the association between leukocyte telomere length and autism has not been investigated. Here we investigated the possible association between relative telomere length (RTL) in peripheral blood leukocytes and childhood autism by using an established real-time polymerase chain reaction method. We observed significantly shorter RTL in patients with childhood autism than in controls (p = 0.006). Individuals with shorter RTL had a significantly increased presence of childhood autism compared with those who had long RTL. In patients, we found that family training interventions have a significant effect on telomere length (P = 0.012), but no correlations between RTL and clinical features (paternal age, maternal age, age of onset, illness of duration, CARS score and ABC score) were observed in this study. These results provided the first evidence that shorter leukocytes telomere length is significantly associated with childhood autism. The molecular mechanism underlying telomere length may be implicated in the development of autism. PMID:25399515

Li, Zongchang; Tang, Jinsong; Li, Hong; Chen, Shan; He, Ying; Liao, Yanhui; Wei, Zhen; Wan, Guobin; Xiang, Xi; Xia, Kun; Chen, Xiaogang

2014-01-01

130

Shorter telomere length in peripheral blood leukocytes is associated with childhood autism  

PubMed Central

Telomeres are protective chromosomal structures that play a key role in preserving genomic stability. Epidemiologic studies have shown that the abnormal telomere length in leukocytes is associated with some mental disorders and age-related diseases. However, the association between leukocyte telomere length and autism has not been investigated. Here we investigated the possible association between relative telomere length (RTL) in peripheral blood leukocytes and childhood autism by using an established real-time polymerase chain reaction method. We observed significantly shorter RTL in patients with childhood autism than in controls (p = 0.006). Individuals with shorter RTL had a significantly increased presence of childhood autism compared with those who had long RTL. In patients, we found that family training interventions have a significant effect on telomere length (P = 0.012), but no correlations between RTL and clinical features (paternal age, maternal age, age of onset, illness of duration, CARS score and ABC score) were observed in this study. These results provided the first evidence that shorter leukocytes telomere length is significantly associated with childhood autism. The molecular mechanism underlying telomere length may be implicated in the development of autism. PMID:25399515

Li, Zongchang; Tang, Jinsong; Li, Hong; Chen, Shan; He, Ying; Liao, Yanhui; Wei, Zhen; Wan, Guobin; Xiang, Xi; Xia, Kun; Chen, Xiaogang

2014-01-01

131

Flow cytofluorometric assay of human whole blood leukocyte DNA degradation in response to Yersinia pestis and Staphylococcus aureus  

NASA Astrophysics Data System (ADS)

Human leukocytes containing less than 2C DNA per cell (damaged or dead cells) were detected and quantified by flow cytometry and DNA-specific staining with ethidium bromide and mithramycin in whole blood infected with Staphylococcus aureus or Yersinia pestis. Addition of live S. aureus to the blood (100 microbe cells per one leukocyte) resulted in rapid degradation of leukocyte DNA within 3 to 6 hours of incubation at 37 degree(s)C. However, only about 50 percent cells were damaged and the leukocytes with the intact genetic apparatus could be found in the blood for a period up to 24 hours. The leukocyte injury was preceded by an increase of DNA per cell content (as compared to the normal one) that was likely to be connected with the active phagocytosis of S. aureus by granulocytes (2C DNA of diploid phagocytes plus the all bacterial DNA absorbed). In response to the same dose of actively growing (at 37 degree(s)C) virulent Y. pestis cells, no increase in DNA content per cell could be observed in the human blood leukocytes. The process of the leukocyte DNA degradation started after a 6-hour incubation, and between 18 to 24 hours of incubation about 90 percent leukocytes (phagocytes and lymphocytes) lost their specific DNA fluorescence. These results demonstrated a high potential of flow cytometry in comparative analysis in vitro of the leukocyte DNA degradation process in human blood in response to bacteria with various pathogenic properties. They agree with the modern idea of an apoptotic mechanism of immunosuppression in plague.

Kravtsov, Alexander L.; Grebenyukova, Tatyana P.; Bobyleva, Elena V.; Golovko, Elena M.; Malyukova, Tatyana A.; Lyapin, Mikhail N.; Kostyukova, Tatyana A.; Yezhov, Igor N.; Kuznetsov, Oleg S.

2001-05-01

132

Biophysical Description of Multiple Events Contributing Blood Leukocyte Arrest on Endothelium  

PubMed Central

Blood leukocytes have a remarkable capacity to bind to and stop on specific blood vessel areas. Many studies have disclosed a key role of integrin structural changes following the interaction of rolling leukocytes with surface-bound chemoattractants. However, the functional significance of structural data and mechanisms of cell arrest are incompletely understood. Recent experiments revealed the unexpected complexity of several key steps of cell-surface interaction: (i) ligand-receptor binding requires a minimum amount of time to proceed and this is influenced by forces. (ii) Also, molecular interactions at interfaces are not fully accounted for by the interaction properties of soluble molecules. (iii) Cell arrest depends on nanoscale topography and mechanical properties of the cell membrane, and these properties are highly dynamic. Here, we summarize these results and we discuss their relevance to recent functional studies of integrin-receptor association in cells from a patient with type III leukocyte adhesion deficiency. It is concluded that an accurate understanding of all physical events listed in this review is needed to unravel the precise role of the multiple molecules and biochemical pathway involved in arrest triggering. PMID:23750158

Robert, Philippe; Touchard, Dominique; Bongrand, Pierre; Pierres, Anne

2013-01-01

133

A three-dimensional atlas of human dermal leukocytes, lymphatics, and blood vessels.  

PubMed

Dendritic cells (DCs), macrophages (M?), and T cells are major components of the skin immune system, but their interstitial spatial organization is poorly characterized. Using four-channel whole-mount immunofluorescence staining of the human dermis, we demonstrated the three-dimensional distribution of CD31(+) blood capillaries, LYVE-1(+) lymphatics, discrete populations of CD11c(+) myeloid DCs, FXIIIa(+) M?, and lymphocytes. We showed phenotypic and morphological differences in situ between DCs and M?. DCs formed the first dermal cellular layer (0-20 ?m beneath the dermoepidermal junction), M? were located deeper (40-60 ?m), and CD3(+) lymphocytes were observed throughout (0-60 ?m). Below this level, DCs, T cells, and the majority of M? formed stable perivascular sheaths. Whole-mount imaging revealed the true extent of dermal leukocytes previously underestimated from cross-section views. The total area of apical dermis (0-30 ?m) contained approximately 10-fold more myeloid DCs than the entire blood volume of an average individual. Surprisingly, <1% of dermal DCs occupied lymphatics in freshly isolated skin. Dermal DCs rapidly accumulated within lymphatics, but M? remained fixed in skin explants cultured ex vivo. The leukocyte architecture observed in normal skin was distorted in inflammation and disease. These studies illustrate the micro-anatomy of dermal leukocytes and provide further insights into their functional organization. PMID:24352044

Wang, Xiao-Nong; McGovern, Naomi; Gunawan, Merry; Richardson, Connor; Windebank, Martin; Siah, Tee-Wei; Lim, Hwee-Ying; Fink, Katja; Li, Jackson L Yao; Ng, Lai G; Ginhoux, Florent; Angeli, Veronique; Collin, Matthew; Haniffa, Muzlifah

2014-04-01

134

Quantitation of cytomegalovirus (CMV) DNA in leukocytes of human immunodeficiency virus-infected subjects with and without CMV disease by using PCR and the SHARP Signal Detection System.  

PubMed

We report the development of a simple and rapid PCR assay for quantitation of the cytomegalovirus (CMV) DNA load in polymorphonuclear leukocytes. Using this system, a very good correlation was found between a high number of CMV copies in the blood and the presence of CMV disease in subjects with AIDS. PMID:9003635

Boivin, G; Handfield, J; Murray, G; Toma, E; Lalonde, R; Lazar, J G; Bergeron, M G

1997-02-01

135

Leukocyte-epithelial interactions.  

PubMed

As a 'double-edged sword', neutrophil (polymorphonuclear leukocyte) migration across epithelial-lined organs is an important component of host defense, but it also results in epithelial pathophysiology and disease symptoms. There have been significant advances in better understanding the mechanisms of how leukocytes cross the vascular endothelium to exit the bloodstream; however, many of the mechanisms that govern polymorphonuclear leukocyte transepithelial migration are different and we are only just beginning to understand them. Recent findings include new junctional adhesion molecules and carbohydrate moieties as receptors for migrating neutrophils. In addition, new insights into leukocyte-epithelial signaling events have emerged that are beginning to shed light on the role of SIRP-CD47 interactions in regulating the rate of neutrophil transepithelial migration and how neutrophils modulate epithelial barrier function. PMID:14519390

Zen, Ke; Parkos, Charles A

2003-10-01

136

TNF{alpha} release from peripheral blood leukocytes depends on a CRM1-mediated nuclear export  

SciTech Connect

Tumor necrosis factor-{alpha} (TNF{alpha}) is a potent pro-inflammatory cytokine that plays a major role in the pathogenesis of acute and chronic inflammatory disorders such as septic shock and arthritis, respectively. Leukocytes stimulated with inflammatory signals such as lipopolysaccharide (LPS) are the predominant producers of TNF{alpha}, and thus control of TNF{alpha} release from stimulated leukocytes represents a potential therapeutic target. Here, we report that leptomycin B (LMB), a specific inhibitor of CRM1-dependent nuclear protein export, inhibits TNF{alpha} release from LPS-stimulated human peripheral blood neutrophils and mononuclear cells. In addition, immunofluorescence confocal microscopy and immunoblotting analysis indicate that TNF{alpha} is localized in the nucleus of human neutrophils and mononuclear cells. This study demonstrates that the cellular release of TNF{alpha} from stimulated leukocytes is mediated by the CRM1-dependent nuclear export mechanism. Inhibition of CRM1-dependent cellular release of TNF{alpha} could thus provide a novel therapeutic approach for disorders involving excessive TNF{alpha} release.

Miskolci, Veronika [Department of Biology, St. John's University, NY 11439 (United States); Department of Pediatrics, Feinstein Institute for Medical Research at the North Shore-Long Island Jewish Health System, New Hyde Park, NY 11040 (United States); Ghosh, Chandra C. [Department of Biology, St. John's University, NY 11439 (United States); Rollins, Janet [Department of Biology, St. John's University, NY 11439 (United States); Romero, Carlos [Department of Biology, St. John's University, NY 11439 (United States); Vu, Hai-Yen [Department of Biology, St. John's University, NY 11439 (United States); Robinson, Staci [Department of Biology, St. John's University, NY 11439 (United States); Davidson, Dennis [Department of Pediatrics, Feinstein Institute for Medical Research at the North Shore-Long Island Jewish Health System, New Hyde Park, NY 11040 (United States); Vancurova, Ivana [Department of Biology, St. John's University, NY 11439 (United States) and Department of Pediatrics, Feinstein Institute for Medical Research at the North Shore-Long Island Jewish Health System, New Hyde Park, NY 11040 (United States)]. E-mail: vancuroi@stjohns.edu

2006-12-15

137

Dietary beta-carotene is taken up by blood plasma and leukocytes in dogs.  

PubMed

beta-Carotene uptake by blood plasma and leukocytes was studied in mature beagle dogs. In expt. 1, dogs were fed once orally with 0, 50, 100 or 200 mg of beta-carotene and their blood was sampled at 0, 1. 5, 3, 6, 10, 18 and 24 h. Plasma beta-carotene concentrations increased dose-dependently to peak at 6 h postfeeding. Concentrations decreased rapidly thereafter, showing a half-life of 3 to 4 h. In expt. 2, dogs were given daily doses for seven consecutive days with 0, 12.5, 25, 50 or 100 mg beta-carotene. Plasma beta-carotene concentrations increased dose-dependently; concentrations after the last dose were two- to fourfold higher than after the first dose. In expt. 3, dogs were fed 0, 50 or 100 mg beta-carotene daily for 30 d. beta-Carotene was elevated in lymphocytes and neutrophils in supplemented dogs. Furthermore, beta-carotene was taken up by the cytosol, mitochondria, microsomes (lymphocytes and neutrophils) and nuclei (lymphocytes only), proving that dogs can absorb beta-carotene. beta-Carotene is taken up by subcellular organelles of blood lymphocytes and neutrophils and in the plasma and leukocytes beta-carotene may have physiological importance as it relates to immunity in dogs. Uptake kinetics indicated that dogs are not an appropriate animal model for studying beta-carotene absorption and metabolism in humans. PMID:10867051

Chew, B P; Park, J S; Weng, B C; Wong, T S; Hayek, M G; Reinhart, G A

2000-07-01

138

Modulatory effect of visible light on chemiluminescence of stimulated and nonstimulated blood leukocytes of carp (Cyprinus carpio, L)  

NASA Astrophysics Data System (ADS)

Irradiation of carp blood leukocytes with a non-laser visible light resulted in a significant inhibition of the spontaneous luminol-dependent chemiluminescence in the cells of a part of the fish. Those leukocytes that were sensitive to the visible light, showed a shorter time-to-peak than the non sensitive, following their stimulation with Ca ionophore. Because a shorter time-to-peak correlates with inflammation, it could be suggested that the visible light susceptible leukocyte reflect a pre-inflammatory state of their donors.

Belotsky, Sandro; Avtalion, Ramy R.; Friedmann, Harry; Lubart, Rachel

1998-12-01

139

Rate of manual leukocyte differentials in dog, cat and horse blood samples using ADVIA 120 cytograms  

PubMed Central

Background Modern automated haematology instruments are capable of performing leukocyte differentials faster, cheaper and with a higher precision than the traditional 100-cell manual differential count. Thus, in human laboratories, criteria are defined for performing a manual review of the blood smear resulting in a marked reduction of manual differential counts. While common in human laboratories, this approach to reducing the number of manual differentials in veterinary laboratories is still not commonly performed. Thus, our aim was to determine the rate and causes of manual leukocyte differentials in a university clinical pathology laboratory using the automated laser-based haematology analyser ADVIA 120. Overall, 14,953 complete blood cell counts from dogs, cats and horses were reviewed. Manual leukocyte differentials were requested if abnormal ADVIA peroxidase and baso cytograms were detected (i.e. suspicion of left shift or atypical lymphocytes/blasts, inappropriate separation of cell populations). Results In 21% of canine, 32% of feline and 20% of equine samples, a manual differential was requested. Indistinct separation of the cell population was present in 10% to 15% of the cases. Depending on the species, atypical lymphocytes were suspected in 2% to 12%, left shift in 13% to 25% and suspicion of blasts was present in less than 0.4% of the cases. Conclusions The obtained results are comparable to those published for human medicine and the rate of manual differentiation could be markedly reduced in veterinary laboratories if microscopic examination was used as a validation procedure rather than as a reflexive substitute for automated differentiation. PMID:24903909

2014-01-01

140

Leukocyte-derived matrix metalloproteinase-9 mediates blood-brain barrier breakdown and is proinflammatory after transient focal cerebral ischemia.  

PubMed

Results of recent studies reveal vascular and neuroprotective effects of matrix metalloproteinase-9 (MMP-9) inhibition and MMP-9 gene deletion in experimental stroke. However, the cellular source of MMP-9 produced in the ischemic brain and the mechanistic basis of MMP-9-mediated brain injury require elucidation. In the present study, we used MMP-9-/- mice and chimeric knockouts lacking either MMP-9 in leukocytes or in resident brain cells to test the hypothesis that MMP-9 released from leukocytes recruited to the brain during postischemic reperfusion contributes to this injury phenotype. We also tested the hypothesis that MMP-9 promotes leukocyte recruitment to the ischemic brain and thus is proinflammatory. The extent of blood-brain barrier (BBB) breakdown, the neurological deficit, and the volume of infarction resulting from transient focal stroke were abrogated to a similar extent in MMP-9-/- mice and in chimeras lacking leukocytic MMP-9 but not in chimeras with MMP-9-containing leukocytes. Zymography and Western blot analysis from these chimeras confirmed that the elevated MMP-9 expression in the brain at 24 h of reperfusion is derived largely from leukocytes. MMP-9-/- mice exhibited a reduction in leukocyte-endothelial adherence and a reduction in the number of neutrophils plugging capillaries and infiltrating the ischemic brain during reperfusion; microvessel immunopositivity for collagen IV was also preserved in these animals. These latter results document proinflammatory actions of MMP-9 in the ischemic brain. Overall, our findings implicate leukocytes, most likely neutrophils, as a key cellular source of MMP-9, which, in turn, promotes leukocyte recruitment, causes BBB breakdown secondary to microvascular basal lamina proteolysis, and ultimately contributes to neuronal injury after transient focal stroke. PMID:15764676

Gidday, Jeffrey M; Gasche, Yvan G; Copin, Jean-C; Shah, Aarti R; Perez, Ronald S; Shapiro, Steven D; Chan, Pak H; Park, T S

2005-08-01

141

Role of nitric oxide in tumor microcirculation. Blood flow, vascular permeability, and leukocyte-endothelial interactions.  

PubMed Central

The present study was designed to define the role of nitric oxide (NO) in tumor microcirculation, through the direct intravital microcirculatory observations after administration of NO synthase (NOS) inhibitor and NO donor both regionally and systemically. More specifically, we tested the following hypotheses: 1) endogenous NO derived from tumor vascular endothelium and/or tumor cells increases and/or maintains tumor blood flow, decreases leukocyte-endothelial interactions, and increases vascular permeability, 2) exogenous NO can increase tumor blood flow via vessel dilatation and decrease leukocyte-endothelial interactions, and 3) NO production and tissue responses to NO are tumor dependent. To this end, a murine mammary adenocarcinoma (MCaIV) and a human colon adenocarcinoma (LS174T) were implanted in the dorsal skinfold chamber in C3H and severe combined immunodeficient mice, respectively, and observed by means of intravital fluorescence microscopy. Both regional and systemic inhibition of endogenous NO by N omega-nitro-L-arginine methyl ester (L-NAME; 100 mumol/L superfusion or 10 mg/kg intravenously) significantly decreased vessel diameter and local blood flow rate. The diameter change was dominant on the arteriolar side. Superfusion of NO donor (spermine NO, 100 mumol/L) increased tumor vessel diameter and flow rate, whereas systemic injection of spermine NO (2.62 mg/kg) had no significant effect on these parameters. Rolling and stable adhesion of leukocytes were significantly increased by intravenous injection of L-NAME. In untreated animals, both MCaIV and LS174T tumor vessels were leaky to albumin. Systemic NO inhibition significantly attenuated tumor vascular permeability of MCaIV but not of LS174T tumor. Immunohistochemical studies, using polyclonal antibodies to endothelial NOS and inducible NOS, revealed a diffuse pattern of positive labeling in both MCaIV and LS174T tumors. Nitrite and nitrate levels in tumor interstitial fluid of MCaIV but not of LS174T were significantly higher than that in normal subcutaneous interstitial fluid. These results support our hypotheses regarding the microcirculatory response to NO in tumors. Modulation of NO level in tumors is a potential strategy for altering tumor hemodynamics and thus improving oxygen, drug, gene vector, and effector cell delivery to solid tumors. Images Figure 5 PMID:9033284

Fukumura, D.; Yuan, F.; Endo, M.; Jain, R. K.

1997-01-01

142

Isoprinosine and levamisole as stimulators of interferon production in blood leukocytes of patients with alcoholic liver cirrhosis.  

PubMed

Blood leukocytes of 16 patients with alcoholic liver cirrhosis and 18 healthy controls were induced for interferon (IFN) production by phytohemagglutinin (PHA) and concanavalin A (ConA) in the presence or absence of isoprinosine and levamisole at concentrations of 10 micrograms/ml and 1 ng/ml. This interferon was neutralized in 87-95% by anti-HuIFN-gamma monoclonal antibodies. In the presence of the drugs the IFN-gamma production was enhanced, however, IFN-gamma titers yielded from leukocytes of cirrhotic patients were still below the titers observed in stimulated and unstimulated blood leukocytes of healthy controls. For example, IFN titers induced by PHA in the presence of levamisole (1 ng/ml) in cirrhotic patients were 2.5 times lower (20.2 +/- 11.1 U/ml) in comparison to healthy subjects (50.6 +/- 27.3 U/ml). PMID:9597085

Daniluk, J; Kandefer-Szersze?, M

1997-01-01

143

RNA-seq Transcriptional Profiling of Peripheral Blood Leukocytes from Cattle Infected with Mycobacterium bovis  

PubMed Central

Bovine tuberculosis, caused by infection with Mycobacterium bovis, is a major endemic disease affecting cattle populations worldwide, despite the implementation of stringent surveillance and control programs in many countries. The development of high-throughput functional genomics technologies, including gene expression microarrays and RNA-sequencing (RNA-seq), has enabled detailed analysis of the host transcriptome to M. bovis infection, particularly at the macrophage and peripheral blood level. In the present study, we have analyzed the peripheral blood leukocyte (PBL) transcriptome of eight natural M. bovis-infected and eight age- and sex-matched non-infected control Holstein-Friesian animals using RNA-seq. In addition, we compared gene expression profiles generated using RNA-seq with those previously generated using the high-density Affymetrix® GeneChip® Bovine Genome Array platform from the same PBL-extracted RNA. A total of 3,250 differentially expressed (DE) annotated genes were detected in the M. bovis-infected samples relative to the controls (adjusted P-value ?0.05), with the number of genes displaying decreased relative expression (1,671) exceeding those with increased relative expression (1,579). Ingenuity® Systems Pathway Analysis (IPA) of all DE genes revealed enrichment for genes with immune function. Notably, transcriptional suppression was observed among several of the top-ranking canonical pathways including Leukocyte Extravasation Signaling. Comparative platform analysis demonstrated that RNA-seq detected a larger number of annotated DE genes (3,250) relative to the microarray (1,398), of which 917 genes were common to both technologies and displayed the same direction of expression. Finally, we show that RNA-seq had an increased dynamic range compared to the microarray for estimating differential gene expression. PMID:25206354

McLoughlin, Kirsten E.; Nalpas, Nicolas C.; Rue-Albrecht, Kévin; Browne, John A.; Magee, David A.; Killick, Kate E.; Park, Stephen D. E.; Hokamp, Karsten; Meade, Kieran G.; O’Farrelly, Cliona; Gormley, Eamonn; Gordon, Stephen V.; MacHugh, David E.

2014-01-01

144

Latency of bovine herpesvirus type 5 (BoHV-5) in tonsils and peripheral blood leukocytes.  

PubMed

Bovine herpesvirus types 1 (BoHV-1) and 5 (BoHV-5) can both establish latency in the trigeminal ganglion. Non-neural sites of latency have been described for BoHV-1 but not for BoHV-5. The aim of this study was to determine whether peripheral blood leukocytes and tonsils are targets for BoHV-5 infection and to establish whether all stages of that virus's infectious cycle can occur in those cell types. Comparisons with BoHV-1 infection of these tissues were also made in order to better understand the pathogenesis of both viruses. BoHV-1 and BoHV-5 were isolated from tonsils of acutely-infected calves. BoHV-5 was also isolated from a tonsil homogenate after dexamethasone-induced reactivation. During latency, infectious virus was recovered from a tonsil explant of one BoHV-5-infected calf. The genomes of BoHV-5 and BoHV-1 were detected in tonsils from acutely-infected calves although were not detected in tonsils from latently-infected calves or from calves treated with dexamethasone. Virus DNA was intermittently detected in leukocytes. The study has shown that BoHV-5 can establish latency in bovine tonsils and peripheral white blood cells, and that it can be reactivated from latently-infected tonsils, which might contribute to viral transmission. The titres of BoHV-1 and BoHV-5 in tonsils were similar, suggesting that replication at this site is a common feature for both viruses. PMID:25155304

Favier, P A; Marin, M S; Morán, P E; Odeón, A C; Verna, A E; Pérez, S E

2014-10-01

145

Virus-specific antibodies interfere with avian influenza infection in peripheral blood mononuclear leukocytes from young or aged chickens  

Technology Transfer Automated Retrieval System (TEKTRAN)

Avian influenza virus (AIV) infection was examined in peripheral blood mononuclear leukocyte cultures (PBMC) that were collected from 1-day-old chicks or from 52-week-old chickens. Virus-specific antibodies were incubated with AIV to model maternal antibody interference in vitro. Interferon-alpha (I...

146

Effects of spaceflight on rat peripheral blood leukocytes and bone marrow progenitor cells  

NASA Technical Reports Server (NTRS)

The white blood cell (WBC) elements and the bone marrow myeloid progenitor cell populations were analyzed to ascertain adaptation to micro-gravity and subsequent readaptation to 1 G in rats flown on the 14-day Spacelab Life Sciences-2 (SLS-2) mission. Bone marrow cells were harvested from one group of rats killed inflight (FD13) and blood was drawn from three other groups at various times. The WBC level was normal on FD14 with the exception of neutrophilia. On FD13, numbers of colony-forming units-granulocyte (CFU-G), CFU-GM, and CFU-M from flight animals were decreased compared with ground controls when incubated with recombinant rat interleukin-3 (rrIL-3) alone or in combination with recombinant human erythropoietin (rhEpo). On recovery (R + 0), flight rats had decreased numbers of total leukocytes and absolute numbers of lymphocytes and monocytes with elevated neutrophils compared with control rats. They had lower numbers of CD4, CD8, CD2, CD3, and B cells in the peripheral blood but no differences in spleen lymphocytes.

Ichiki, A. T.; Gibson, L. A.; Jago, T. L.; Strickland, K. M.; Johnson, D. L.; Lange, R. D.; Allebban, Z.

1996-01-01

147

Red blood cells are a sink for interleukin 8, a leukocyte chemotaxin.  

PubMed Central

IL-8 (also known as neutrophil-activating peptide 1) is recognized as a potent effector of neutrophil functions. Several different cell types that contact blood, namely T lymphocytes, monocytes, and endothelial cells, secrete this polypeptide following stimulation by cytokines, or lipopolysaccharide. Here we show that when IL-8 is added to blood it rapidly partitions from the plasma fluid to the blood cells and that erythrocytes account for the vast majority of this binding. Analysis of 125I-IL-8 binding [( ala-IL-8]77 form) to human red cells indicates a single, 5 nM Kd affinity class of binding sites, present at approximately 2,000 per red cell representing approximately 15 nmol of red cell IL-8 binding sites per liter of blood. These sites are protease sensitive. Their binding of IL-8 is rapidly reversible and does not result in receptor internalization, although bound IL-8 is resistant to extraction by pH 3 buffer at 5 degrees C. 125I-IL-8 binding to red cells was not inhibited by epidermal growth factor or interleukin 1, but was inhibited by monocyte chemotactic peptide-1, which is not a neutrophil chemotaxin, but is a member of the same family of polypeptides as IL-8. FACS analysis of IL-8-mediated mobilization of Ca2+ in neutrophils indicates that the IL-8 bound to red cells is incapable of stimulating neutrophils. Thus, red cell absorption of IL-8 may function to limit stimulation of leukocytes by IL-8 released into blood. Images PMID:1918386

Darbonne, W C; Rice, G C; Mohler, M A; Apple, T; Hébert, C A; Valente, A J; Baker, J B

1991-01-01

148

EXPERIMENTAL MASTITIS WITH ESCHERICHIA COLI: SEQUENTIAL RESPONSE OF LEUKOCYTES AND OPSONIC ACTIVITY  

E-print Network

EXPERIMENTAL MASTITIS WITH ESCHERICHIA COLI: SEQUENTIAL RESPONSE OF LEUKOCYTES AND OPSONIC ACTIVITY infusion of bacteria (Hill, 1979); b) opsonic activity is required in milk to enable polymorphonuclear

Paris-Sud XI, Université de

149

Flow cytometric detection of hepatitis C virus antigens in infected peripheral blood leukocytes: Binding and entry  

PubMed Central

AIM: We designed two synthetic-core-specific peptides core 1 (C1) and core 2 (C2), and an E1-specific peptide (E1). We produced specific polyclonal antibodies against these peptides and used the antibodies for detection of HCV antigens on surface and within infected peripheral blood leukocytes. METHODS: Peripheral blood from a healthy individual who tested negative for HCV RNA was incubated with HCV type 4 infected serum for 1 h and 24 h at 37 °C. Cells were stained by direct and indirect immunofluorescence and measured by flow cytometry. RESULTS: After 1 h of incubation, antibodies against C1, C2, and E1 detected HCV antigens on the surface of 27%, 26% and 73% of monocytes respectively, while 10%, 5% and 9% of lymphocytes were positive with anti-C1, anti-C2 and anti-E1 respectively. Only 1-3% of granulocytes showed positive staining with anti-C1, anti-C2 and anti E1 antibodies. After 24 h of incubation, we found no surface staining with anti-C1, anti-C2 or anti-E1. Direct immunostaining using anti-C2 could not detect intracellular HCV antigens, after 1 h of incubation with the virus, while after 24 h of incubation, 28% of infected cells showed positive staining. Only plus strand RNA was detectable intracellularly as early as 1 h after incubation, and remained detectable throughout 48 h post-infection. Interestingly, minus RNA strand could not be detected after 1 h, but became strongly detectable intracellularly after 24 h post-infection. CONCLUSION: Monocytes and lymphocytes are the preferred target cells for HCV infection in peripheral blood leukocytes. Our specific anti-core and anti-E1 antibodies are valuable reagents for demonstration of HCV cell cycle. Also, HCV is capable of infecting and replicating in peripheral blood mononuclear cells as confirmed by detection of minus strand HCV RNA as well as intracellular staining of core HCV antigen. PMID:16127753

El-Awady, Mostafa K; Tabll, Ashraf A; Redwan, El-Rashdy M; Youssef, Samar; Omran, Moataza H; Thakeb, Fouad; El-Demellawy, Maha

2005-01-01

150

Forces on a Wall-Bound Leukocyte in a Small Vessel Due to Red Cells in the Blood Stream  

PubMed Central

As part of the inflammation response, white blood cells (leukocytes) are well known to bind nearly statically to the vessel walls, where they must resist the force exerted by the flowing blood. This force is particularly difficult to estimate due to the particulate character of blood, especially in small vessels where the red blood cells must substantially deform to pass an adhered leukocyte. An efficient simulation tool with realistically flexible red blood cells is used to estimate these forces. At these length scales, it is found that the red cells significantly augment the streamwise forces that must be resisted by the binding. However, interactions with the red cells are also found to cause an average wall-directed force, which can be anticipated to enhance binding. These forces increase significantly as hematocrit values approach 25% and decrease significantly as the leukocyte is made flatter on the wall. For a tube hematocrit of 25% and a spherical protrusion with a diameter three-quarters that of the vessel, the average forces are increased by ?40% and the local forces are more than double those estimated with an effective-viscosity-homogenized blood. Both the enhanced streamwise and wall-ward forces and their unsteady character are potentially important in regard to binding mechanisms. PMID:23062353

Isfahani, Amir H.G.; Freund, Jonathan B.

2012-01-01

151

Flow cytometric assay for analysis of cytotoxic effects of potential drugs on human peripheral blood leukocytes  

NASA Astrophysics Data System (ADS)

Toxicity test of new chemicals belongs to the first steps in the drug screening, using different cultured cell lines. However, primary human cells represent the human organism better than cultured tumor derived cell lines. We developed a very gentle toxicity assay for isolation and incubation of human peripheral blood leukocytes (PBL) and tested it using different bioactive oligopeptides (OP). Effects of different PBL isolation methods (red blood cell lysis; Histopaque isolation among others), different incubation tubes (e.g. FACS tubes), anticoagulants and blood sources on PBL viability were tested using propidium iodide-exclusion as viability measure (incubation time: 60 min, 36°C) and flow cytometry. Toxicity concentration and time-depended effects (10-60 min, 36 °C, 0-100 ?g /ml of OP) on human PBL were analyzed. Erythrocyte lysis by hypotonic shock (dH2O) was the fastest PBL isolation method with highest viability (>85%) compared to NH4Cl-Lysis (49%). Density gradient centrifugation led to neutrophil granulocyte cell loss. Heparin anticoagulation resulted in higher viability than EDTA. Conical 1.5 mL and 2 mL micro-reaction tubes (both polypropylene (PP)) had the highest viability (99% and 97%) compared to other tubes, i.e. three types of 5.0 mL round-bottom tubes PP (opaque-60%), PP (blue-62%), Polystyrene (PS-64%). Viability of PBL did not differ between venous and capillary blood. A gentle reproducible preparation and analytical toxicity-assay for human PBL was developed and evaluated. Using our assay toxicity, time-course, dose-dependence and aggregate formation by OP could be clearly differentiated and quantified. This novel assay enables for rapid and cost effective multiparametric toxicological screening and pharmacological testing on primary human PBL and can be adapted to high-throughput-screening.°z

Nieschke, Kathleen; Mittag, Anja; Golab, Karolina; Bocsi, Jozsef; Pierzchalski, Arkadiusz; Kamysz, Wojciech; Tarnok, Attila

2014-03-01

152

Correlation of adrenomedullin gene expression in peripheral blood leukocytes with severity of ischemic stroke.  

PubMed

Human adrenomedullin (ADM), a 52-amino acid peptide, belongs to the calcitonin/calcitonin gene-related peptide (CGRP)/amylin peptide family. ADM acts as a multifunctional regulatory peptide and is upregulated in response to hypoxia. Previous microarray studies have found increased ADM gene (ADM) expression in peripheral blood cells of patients with stroke, however, it is unknown if an increased ADM level is correlated with severity of human ischemic stroke. This study investigated ADM expression in peripheral blood leukocytes (PBL) of healthy controls and subjects at day 1, week 1 and week 3 postacute ischemic stroke using rtPCR methodology. We found that ADM expression was significantly upregulated on the first day of stroke compared to the healthy subjects and the disease controls; the levels remained elevated for up to week 3. Further, ADM expression at day 1 was correlated with stroke severity measured by the National Institute of Healthy Stroke Scale (NIHSS), the modified Barthel Index (mBI) and the modified Rankin Scale (mRS). This could indicate that ADM expression level is related to the severity of tissue damage. We suggest that increased ADM expression in PBL after acute ischemic stroke is most likely to indicate that these cells have been subjected to hypoxia and that the magnitude of expression is likely to be related to the volume of hypoxic tissue. Hypoxia can affect lymphocytes function and could affect the immune response to stroke. The correlation of ADM expression level with the measures of stroke severity implicates ADM--a potential blood bio-marker in studies of ischemic stroke. PMID:23968191

Liu, Jia; Yan, Jun; Greer, Judith M; Read, Stephen J; Henderson, Robert D; Rose, Stephen E; Coulthard, Alan; McCombe, Pamela A

2014-04-01

153

Tumor necrosis factor and interferon production by peripheral blood leukocytes of patients with alcoholic cirrhosis.  

PubMed

Sixteen male and female patients with alcoholic cirrhosis and 13 healthy controls were included in the study. The level of interferon (IFN) and tumor necrosis factor (TNF) activity was examined in the sera and also in cultures in peripheral blood leukocytes (PBL) after in vitro stimulation with the cytokine inducers. In sera of patients with alcoholic cirrhosis higher IFN and TNF levels were detected than in controls. However, after induction with Newcastle disease virus (NDV), phytohemagglutinin M (PHA) and lipopolysaccharide from E. coli (LPS), PBL from cirrhotic patients produced lower IFN levels in comparison to controls. In contrast to depressed ability to produce IFNs, TNF production was higher in PBL of cirrhotic patients induced by PHA and a low dose of LPS (1 microgram/ml). NDV induced comparable levels of TNF in both groups. It appears likely that cells of cirrhotic patients were suppressed by an unknown factor or were hyporeactive for IFN production, but synthesis and release of TNF was enhanced, suggesting that cells producing TNF were preactivated in vivo. Mechanism of such preactivation is discussed. PMID:8915512

Daniluk, J; Kandefer-Szerszen, M; Borowska, L

1996-01-01

154

Genome Wide Peripheral Blood Leukocyte DNA Methylation Microarrays Identified a Single Association with Inflammatory Bowel Diseases  

PubMed Central

Background Crohn disease (CD) and ulcerative colitis (UC) are common forms of inflammatory bowel diseases (IBD). Monozygotic (MZ) twin discordance rates and epidemiologic data implicate that environmental changes and epigenetic factors may play a pathogenic role in IBD. DNA methylation (the methylation of cytosines within CpG dinucleotides) is an epigenetic modification, which can respond to environmental influences. We investigated whether DNA methylation might be connected with IBD in peripheral blood leukocyte (PBL) DNA by utilizing genome-wide microarrays. Methods Two different high-throughput microarray based methods for genome wide DNA methylation analysis were employed. First, DNA isolated from MZ twin pairs concordant (CD: 4; UC: 3) and discordant (CD: 4; UC: 7) for IBD was interrogated by a custom made methylation specific amplification microarray (MSAM). Second, the recently developed Illumina Infinium HumanMethylation450 BeadChip arrays were used on 48 samples of PBL DNA from discordant MZ twin pairs (CD:3; UC:3) and treatment naive pediatric cases of IBD (CD:14; UC:8), as well as controls (n=14). The microarrays were validated with bisulfite pyrosequencing. Results The Methylation BeadChip approach identified a single DNA methylation association of IBD at TEPP (testis, prostate and placenta-expressed protein) when DNA isolated selectively from peripheral blood mononuclear cells was analyzed (8.6% increase in methylation between CD and control, FDR=0.0065). Conclusions Microarray interrogation of IBD dependent DNA methylation from PBLs appears to have limited ability to detect significant disease associations. More detailed and/or selective approaches may be useful for the elucidation of connections between the DNA methylome and IBD in the future. PMID:22467598

Harris, R. Alan.; Nagy-Szakal, Dorottya; Pedersen, Natalia; Opekun, Antone; Bronsky, Jiri; Munkholm, Pia; Jespersgaard, Cathrine; Andersen, Paal Skytt; Melegh, Bela; Ferry, George; Jess, Tine; Kellermayer, Richard

2012-01-01

155

Leukocyte orchestration in blood and tumour tissue following interleukin-2 based immunotherapy in metastatic renal cell carcinoma  

Microsoft Academic Search

With the objective of evaluating leukocyte orchestration in situ, serial blood samples and tumour tissue core needle biopsies were obtained at baseline and repeated after 1 month of therapy, among 49 consecutive single-institution patients with metastatic renal cell carcinoma (mRCC). Patients were treated with outpatient low-dose subcutaneous interleukin 2 (IL-2) and interferon a (IFN-a) alone ( n=23) or in combination with

Frede Donskov; Karen Marie Bennedsgaard; Marianne Hokland; Niels Marcussen; Rune Fisker; Hans Henrik Torp Madsen; Kirsten Fode; Hans von der Maase

2004-01-01

156

Activation of human leukocytes on tantalum trabecular metal in comparison to commonly used orthopedic metal implant materials.  

PubMed

We analyzed leukocyte functions and cytokine response of human leukocytes toward porous tantalum foam biomaterial (Trabecular Metaltrade mark, TM) in comparison to equally sized solid orthopedic metal implant materials (pure titanium, titanium alloy, stainless steel, pure tantalum, and tantalum coated stainless steel). Isolated peripheral blood mononuclear cells (PBMC) and polymorphonuclear neutrophil leukocytes (PMN) were cocultured with equally sized metallic test discs for 24 h. Supernatants were analyzed for cytokine content by enzyme-linked immunosorbent assay. Compared to the other used test materials there was a significant increase in the release of IL (interleukin)-1ra and IL-8 from PMN, and of IL-1ra, IL-6, and TNF-alpha from PBMC in response to the TM material. The cytokine release correlated with surface roughness of the materials. In contrast, the release of IL-2 was not induced showing that mainly myeloid leukocytes were activated. In addition, supernatants of these leukocyte/material interaction (conditioned media, CM) were subjected to whole blood cell function assays (phagocytosis, chemotaxis, bacterial killing). There was a significant increase in the phagocytotic capacity of leukocytes in the presence of TM-conditioned media. The chemotactic response of leukocytes toward TM-conditioned media was significantly higher compared to CM obtained from other test materials. Furthermore, the bactericidal capacity of whole blood was enhanced in the presence of TM-conditioned media. These results indicate that leukocyte activation at the surface of TM material induces a microenvironment, which may enhance local host defense mechanisms. PMID:18286637

Schildhauer, T A; Peter, E; Muhr, G; Köller, M

2009-02-01

157

Is the mean blood leukocyte telomere length a predictor for sporadic thoracic aortic aneurysm? Data from a preliminary study.  

PubMed

Telomeres have been postulated as a universal clock that shortens in parallel with cellular aging. They are specialized DNA-protein structures at the ends of chromosome with remarkable functions--preventing their recognition as double-stranded DNA breaks, protecting their recombination and degradation, and avoiding a DNA damage cellular response. Telomere shortening is currently considered the best aging marker, but is also a predictor for age-related diseases, including cardiovascular diseases. Biological age clearly seems to be a better predictor of vascular risk rather than chronological age. This concept is supported by key assumptions that peripheral blood leukocyte telomere content accurately reflects that of the vascular wall and its decrease is associated with premature vascular disease. Thus, we are analyzing whether the mean of blood leukocyte telomere length might also be a predictor for sporadic thoracic aortic aneurysm (S-TAA). The preliminary results seem to be promising. Shorter telomeres were detected in patients than in controls. Thus, mean of blood leukocyte telomere length could contribute to identify individuals at S-TAA risk. PMID:22533425

Balistreri, Carmela Rita; Pisano, Calogera; Merlo, Daniele; Fattouch, Khalil; Caruso, Marco; Incalcaterra, Egle; Colonna-Romano, Giuseppina; Candore, Giuseppina

2012-04-01

158

Effect of gold nanoparticles on production of reactive oxygen species by human peripheral blood leukocytes stimulated with opsonized zymosan.  

PubMed

We studied the effect of gold nanoparticles on ROS production by leukocytes. ROS production was detected by luminol-dependent chemiluminescence (LDCL) of human peripheral blood leukocytes stimulated with opsonized zymosan. Nanoparticle size was 5, 10 and 30 nm. Simultaneous addition of nanoparticles and opsonized zymosan showed that 5-nm nanoparticles inhibited LDCL intensity in comparison with the control, when LDCL recording was conducted in the presence of opsonized zymosan. Increasing nanoparticle size from 5 up to 30 nm enhanced LDCL intensity. Preincubation of gold nanoparticles with autologous blood plasma increased LDCL intensity. In the control (without gold nanoparticles), blood plasma produced no activating effect on LDCL. We found that the effect of gold nanoparticles on leukocyte LDCL depended on nanoparticle size: 10- and 30-nm nanoparticles inhibited LDCL intensity in comparison with the control (incubation in the absence of nanoparticles) irrespective of the duration of incubation, while 5-nm gold nanoparticles had no effect on LDCL intensity. Incubation of gold nanoparticles with autologous plasma increased LDCL intensity if nanoparticle size was 30 and 10 nm. PMID:24319701

Piryazev, A P; Azizova, O A; Aseichev, A V; Dudnik, L B; Sergienko, V I

2013-11-01

159

Effects of protected fish oil in the diet of periparturient dairy goats on phenotypic variation in blood and milk leukocytes.  

PubMed

The goal of this study was to evaluate the effects of dietary protected fish oil (FO) on phenotypic variation in blood, milk leukocytes, and some productive and metabolic parameters in periparturient dairy goats. About 12 Alpine goats, selected from a larger group of second-parity animals, were fed from 15 days before kidding until the 15th day of lactation with the same basal diet that had been supplemented with either 47 g/head per day of FO or 47 g/head per day hydrogenated palm oil (PO). Dry matter intake, live body weight (LBW), body condition score (BCS), and productive performance were evaluated in 2 weeks after kidding. On days 15, 7, and 2 before kidding and days 2, 7, and 15 after kidding, plasma samples were collected for evaluation of alanine aminotransferase, aspartate aminotransferase, non-esterified fatty acids, glucose, beta-hydroxybutyrate, cholesterol, and urea levels. White blood cell and blood leukocyte subsets were counted in whole blood samples on the kidding day, as well as at 1, 4, and 15 days after kidding. In addition, milk somatic cell count, intramammary infection (IMI), and milk leukocyte subsets were evaluated on days 4 and 15 after kidding. No differences were observed in dry matter intake and BCS, while LBW was higher in FO-fed animals. Milk production and composition, plasma metabolites, and liver enzymes were similar in both experimental groups. Blood CD4 positive cells increased constantly (P = 0.05) in FO-fed group, while CD8 and CD14 cell counts significantly increased 4 days after kidding (P < 0.01). Milk leukocyte subsets showed a significant (P < 0.01) decrease in PO-fed group and a non-significant increase (P = 0.34) in FO-fed group, despite the presence of coagulase negative staphylococci IMI. The results of the productive performance evaluation agreed with those of many other studies, which did not find any significant differences between dairy goats fed diets enriched with FO or PO supplements. The administration of FO to dairy goats in transition appeared to affect the variation in blood leukocytes with a constant increase in CD4- and CD8-positive cells in comparison with a PO fat-supplemented diet. PMID:22444697

Bronzo, V; Puricelli, M; Agazzi, A; Invernizzi, G; Ferroni, M; Moroni, P; Savoini, G

2010-09-01

160

[Effect of high doses of shark liver oil supplementation on T cell polarization and peripheral blood polymorphonuclear cell function].  

PubMed

Fish oils supplementation has been recently widely used in prevention and treatment of the diseases in humans. Fish oil beneficial effects have been investigated in a number of animal disease models as well as human studies. Here, we examined clinical, immunological and biochemical effects of shark liver oil supplementation in high doses in 13 volunteers. The experiment was based on the consumption of 3.6 g of squalene, 3.6 g of alkylglycerols and 750 mg of n-3 polyunsaturated fatty acids (PUFA) per day for 4 weeks. We have shown the increased response of neutrophils towards bacteria, the increased level of C4 component of complement in blood, the rise of total antioxidant status of serum, and the predominance of Type I cytokine IFN-gamma, TNF-alpha and IL-2 production by peripheral blood mononuclear cells after shark liver oil intake. Moreover, shark liver oil supplementation markedly affect lipid metabolism and cholesterol balance. The increase of total cholesterol level from 182.92 +/- 29.290 mg/dl before oil consumption to 224.46 +/- 62.198 mg/dl after diet rich in oil, and the decrease of HDL fraction were noted. However, metabolism of lipids normalised spontaneously after the end of the experiment in all the individuals. The results of the present study have shown, that the main effects of shark liver oil are the result of the biological activity of squalene and 1-O-alkylglycerols, which dominate in the composition of the oil quantitatively. On the contrary, anti-inflammatory effects of n-3 PUFA do not manifest, when taking together with high doses of squalene and alkylglycerols. On the bases of these observations, we propose that shark liver oil supplementation in high doses is beneficial in bacterial, viral and fungal infections, whereas patients with atherosclerosis or autoimmune diseases should avoid the consumption of high amounts of shark liver oil. PMID:16124384

Lewkowicz, Przemys?aw; Banasik, Ma?gorzata; G?owacka, Ewa; Lewkowicz, Natalia; Tchórzewski, Henryk

2005-06-01

161

Age-Related Changes following In Vitro Stimulation with Rhodococcus equi of Peripheral Blood Leukocytes from Neonatal Foals  

PubMed Central

Rhodococcus equi is an intracellular bacterium primarily known as an equine pathogen that infects young foals causing a pyogranulomatuous pneumonia. The molecular mechanisms mediating the immune response of foals to R. equi are not fully elucidated. Hence, global genomic high-throughput tools like gene expression microarrays might identify age-related gene expression signatures and molecular pathways that contribute to the immune mechanisms underlying the inherent susceptibility of foals to disease caused by R. equi. The objectives of this study were 2-fold: 1) to compare the expression profiles at specific ages of blood leukocytes from foals stimulated with virulent R. equi with those of unstimulated leukocytes; and, 2) to characterize the age-related changes in the gene expression profile associated with blood leukocytes in response to stimulation with virulent R. equi. Peripheral blood leukocytes were obtained from 6 foals within 24 hours (h) of birth (day 1) and 2, 4, and 8 weeks after birth. The samples were split, such that half were stimulated with live virulent R. equi, and the other half served as unstimulated control. RNA was extracted and the generated cDNA was labeled with fluorescent dyes for microarray hybridizations using an equine microarray. Our findings suggest that there is age-related differential expression of genes involved in host immune response and immunity. We found induction of genes critical for host immunity against pathogens (MHC class II) only at the later time-points (compared to birth). While it appears that foals up to 8-weeks of age are able to initiate a protective inflammatory response against the bacteria, relatively decreased expression of various other immune-related genes points toward inherent diminished immune responses closer to birth. These genes and pathways may contribute to disease susceptibility in foals if infected early in life, and might thus be targeted for developing preventative or therapeutic strategies. PMID:23690962

Kachroo, Priyanka; Ivanov, Ivan; Seabury, Ashley G.; Liu, Mei; Chowdhary, Bhanu P.; Cohen, Noah D.

2013-01-01

162

Maitake beta-glucan promotes recovery of leukocytes and myeloid cell function in peripheral blood from paclitaxel hematotoxicity.  

PubMed

Bone marrow myelotoxicity is a major limitation of chemotherapy. While granulocyte colony stimulating factor (G-CSF) treatment is effective, alternative approaches to support hematopoietic recovery are sought. We previously found that a beta-glucan extract from maitake mushroom Grifola frondosa (MBG) enhanced colony forming unit-granulocyte monocyte (CFU-GM) activity of mouse bone marrow and human hematopoietic progenitor cells (HPC), stimulated G-CSF production and spared HPC from doxorubicin toxicity in vitro. This investigation assessed the effects of MBG on leukocyte recovery and granulocyte/monocyte function in vivo after dose intensive paclitaxel (Ptx) in a normal mouse. After a cumulative dose of Ptx (90-120 mg/kg) given to B6D2F1mice, daily oral MBG (4 or 6 mg/kg), intravenous G-CSF (80 microg/kg) or Ptx alone were compared for effects on the dynamics of leukocyte recovery in blood, CFU-GM activity in bone marrow and spleen, and granulocyte/monocyte production of reactive oxygen species (ROS). Leukocyte counts declined less in Ptx + MBG mice compared to Ptx-alone (p = 0.024) or Ptx + G-CSF treatment (p = 0.031). Lymphocyte levels were higher after Ptx + MBG but not Ptx + G-CSF treatment compared to Ptx alone (p < 0.01). MBG increased CFU-GM activity in bone marrow and spleen (p < 0.001, p = 0.002) 2 days after Ptx. After two additional days (Ptx post-day 4), MBG restored granulocyte/monocyte ROS response to normal levels compared to Ptx-alone and increased ROS response compared to Ptx-alone or Ptx + G-CSF (p < 0.01, both). The studies indicate that oral MBG promoted maturation of HPC to become functionally active myeloid cells and enhanced peripheral blood leukocyte recovery after chemotoxic bone marrow injury. PMID:20140432

Lin, Hong; de Stanchina, Elisa; Zhou, Xi Kathy; Hong, Feng; Seidman, Andrew; Fornier, Monica; Xiao, Wei-Lie; Kennelly, Edward J; Wesa, Kathleen; Cassileth, Barrie R; Cunningham-Rundles, Susanna

2010-06-01

163

Maitake beta-glucan promotes recovery of leukocytes and myeloid cell function in peripheral blood from paclitaxel hematotoxicity  

PubMed Central

Bone marrow myelotoxicity is a major limitation of chemotherapy. While granulocyte colony stimulating factor (G-CSF) treatment is effective, alternative approaches to support hematopoietic recovery are sought. We previously found that a beta-glucan extract from maitake mushroom Grifola frondosa (MBG) enhanced colony forming unit-granulocyte monocyte (CFU-GM) activity of mouse bone marrow and human hematopoietic progenitor cells (HPC), stimulated G-CSF production and spared HPC from doxorubicin toxicity in vitro. This investigation assessed the effects of MBG on leukocyte recovery and granulocyte/monocyte function in vivo after dose intensive paclitaxel (Ptx) in a normal mouse. After a cumulative dose of Ptx (90–120 mg/kg) given to B6D2F1 mice, daily oral MBG (4 or 6 mg/kg), intravenous G-CSF (80 ?g/kg) or Ptx alone were compared for effects on the dynamics of leukocyte recovery in blood, CFU-GM activity in bone marrow and spleen, and granulocyte/monocyte production of reactive oxygen species (ROS). Leukocyte counts declined less in Ptx + MBG mice compared to Ptx-alone (p = 0.024) or Ptx + G-CSF treatment (p = 0.031). Lymphocyte levels were higher after Ptx + MBG but not Ptx + G-CSF treatment compared to Ptx alone (p < 0.01). MBG increased CFU-GM activity in bone marrow and spleen (p < 0.001, p = 0.002) 2 days after Ptx. After two additional days (Ptx post-day 4), MBG restored granulocyte/monocyte ROS response to normal levels compared to Ptx-alone and increased ROS response compared to Ptx-alone or Ptx + G-CSF (p < 0.01, both). The studies indicate that oral MBG promoted maturation of HPC to become functionally active myeloid cells and enhanced peripheral blood leukocyte recovery after chemotoxic bone marrow injury. PMID:20140432

Lin, Hong; de Stanchina, Elisa; Zhou, Xi Kathy; Hong, Feng; Seidman, Andrew; Fornier, Monica; Xiao, Wei-Lie; Kennelly, Edward J.; Wesa, Kathleen; Cassileth, Barrie R.

2011-01-01

164

White blood cell counts, leukocyte ratios, and eosinophils as inflammatory markers in patients with coronary artery disease.  

PubMed

Inflammation is a key feature of atherosclerosis and its clinical manifestations. The leukocyte count has emerged as a marker of inflammation that is widely available in clinical practice. Since inflammation plays a key role in atherosclerosis and its end results, discovering new biomarkers of inflammation becomes important in order to help diagnostic accuracy and provide prognostic information about coronary cardiac disease. In acute coronary syndromes and percutaneous coronary intervention, elevated levels of almost all subtypes of white blood cell counts, including eosinophils, monocytes, neutrophils, and lymphocytes, and neutrophil-lymphocyte ratio and eosinophil-leukocyte ratio constitute independent predictors of adverse outcomes. Eosinophil count and eosinophil-leukocyte ratio, in particular, emerge as novel biomarkers for risk stratification in patients with coronary artery disease. Since the presence of eosinophils denotes hypersensitivity inflammation and hypersensitivity associated with Kounis syndrome, this reality is essential for elucidating the etiology of inflammation in order to consider predictive and preventive measures and to apply the appropriate therapeutic methods. PMID:24770327

Kounis, Nicholas G; Soufras, George D; Tsigkas, Grigorios; Hahalis, George

2015-03-01

165

Microchannel array flow analyzer for measurement of whole blood rheology and flow characteristics of leukocytes activated by bacterial stimulation  

NASA Astrophysics Data System (ADS)

Microgrooves (width 6, 7, and 8 micrometer, each with length 20, 30, and 40 micrometers, respectively; depth 4.5 micrometers; number 4704 in parallel of one size per chip; chip dimensions 12 multiplied by 12 mm) photofabricated in the surface of a single-crystal silicon substrate were converted to leak-proof microchannels by tightly covering them with an optically flat glass plate. Using the microchannels as a model of physiological capillaries, total flow rate of heparinized whole blood taken from healthy subjects was determined under a constant suction of 20 cmH2O, while flow behavior of blood cells through individual channels was microscopically observed. The apparent viscosity (ratio to that of saline) of whole blood was obtained as 4.7 plus or minus 0.5, 3.7 plus or minus 0.3, and 3.4 plus or minus 0.2 (mean plus or minus SD, n equals 4) for 6, 7, and 8 micrometer width channels, respectively. Normal leukocytes passed, showing a round shape, through the channels much more slowly then erythrocytes, but caused no appreciable interference with passage of erythrocytes. Meanwhile, cells exposed to the chemotactic peptide FMLP (1 - 10 nM) and bacterial cells (Escherichia coli K 12; 6 multiplied by 106/ml) slowed further greatly, showing very irregular shapes, and eventually blocked the channels. Such a response of leukocytes took place immediately after the exposure to FMLP, but it appeared gradually with time after the exposure to the cells.

Kikuchi, Yuji; Fujieda, Sadao; Kikuchi, Hiroko E.

1997-03-01

166

Inhibition of peripheral blood neutrophil oxidative burst in periodontitis patients with a homeopathic medication Traumeel S  

PubMed Central

Summary Background The anti-inflammatory effects of a homeopathic remedy, Traumeel S, have been observed in experimental and clinical studies; however, its antioxidant properties have not been elucidated. The aim of the present study was to evaluate the antioxidant effects of Traumeel S on peripheral blood neutrophils in patients with periodontitis. Material/Methods The study was performed using venous blood of 22 individuals with chronic periodontitis and 21 healthy subjects. The antioxidant effects of Traumeel S on the production of reactive oxygen species by unstimulated and stimulated with unopsonized E. coli neutrophils were investigated using luminol- and lucigenin-dependent chemiluminescence (CL). Results Polymorphonuclear leukocytes of periodontitis patients produced higher levels (p<0.01) of light output of lucigenin-dependent chemiluminescence and significantly reduced (p<0.01) light output of luminol-dependent chemiluminescence than analogous cells of healthy subjects. Highly diluted (10?4 of the stem solution) Traumeel S significantly (by approximately 50%) reduced superoxide-induced oxidation of lucigenin by unstimulated and stimulated with unopsonized E. coli polymorphonuclear leukocytes of periodontitis patients and had a tendency to intensify luminol-dependent chemiluminescence. Preincubation of the unstimulated and stimulated with unopsonized E. coli polymorphonuclear leukocytes of healthy subjects with Traumeel S exerts no inhibitory action on the luminol- and lucigenin-dependent chemiluminescence of the above-mentioned cells. Conclusions This study indicates that Traumeel S may significantly reduce production of superoxide anion by unstimulated and stimulated peripheral blood polymorphonuclear neutrophils of periodontitis patients. PMID:21525811

žilinskas, Juozas; žekonis, Jonas; žekonis, Gediminas; Šadzevi?ien?, Renata; Sapragonien?, Marija; Navickait?, Justina; Barzdžiukait?, Ingrida

2011-01-01

167

Development of methods to examine the effects of atmospheric particulate matter (PM) on human peripheral blood leukocytes  

NASA Astrophysics Data System (ADS)

In vitro methods to study the effect of atmospheric particulate matter (PM) on leukocyte function using human peripheral blood were developed. These methods were demonstrated using the blood of 1-5 individuals and National Institute of Standards and Technology (NIST) urban PM #1648, diesel PM #1650, silica PM, and a locally collected PM sample (New Jersey PM10). For the blood samples analyzed in this study NIST urban PM and New Jersey PM10 treatment mediated the release of granule contents from peripheral blood leukocytes and induced structural changes associated with degranulation. Flow cytometry revealed PM-induced changes in phagocytosis and cell structure associated with degranulation. Transmission electron microscopy confirmed NIST urban PM-induced cell structure changes were associated with PM internalization. Colorametric and electrophoretic methods showed no PM-induced release of primary granules and a slight PM-induced release of secondary granules associated with only NIST urban PM. Enzyme Immunosorbent Assays detected increased histamine release from basophils treated with NIST urban PM, a locally collected PM, and the soluble and insoluble components of these particles. NIST urban PM was found to be a potent inducer of histamine release in 4 out of 6 individuals tested. Fractionation studies revealed that soluble (aqueous) and insoluble fractions of NIST urban PM contain histamine-releasing activity. This was also demonstrated for the New Jersey PM10 sample for which the soluble fraction exhibited the most activity. Complementary studies with inhibitors of IgE-mediated histamine release conducted on one test subject suggest that PM-induced histamine release was partially mediated by IgE. A new hypothesis has been formed, suggesting that particle toxicity is related to PM-induced histamine release. Due to the bioactive nature of histamine and its association with many cardiopulmonary responses, the PM- mediated release of histamine should be investigated further.

Zussman, Lisa Ann

168

Analysis of the thiol status of peripheral blood leukocytes in rheumatoid arthritis patients  

Microsoft Academic Search

Although the exact etiology of rheuma- toid arthritis (RA) remains unknown, there is in- creasing evidence that reactive oxygen species and a pro-oxidant\\/antioxidant imbalance are an impor- tant part of the pathogenesis of joint tissue injury. Flow cytometry was used to evaluate the thiol sta- tus (surface-thiols and intracellular glutathione (iGSH)) of leukocytes from RA patients and con- trols. Levels

Robert B. Zurier; David A. Lawrence

2007-01-01

169

Synergistic effects of high blood cholesterol and hypertension on leukocyte and platelet recruitment in the cerebral microcirculation.  

PubMed

Hypertension or hypercholesterolemia can induce a proinflammatory and prothrombogenic phenotype in the microcirculation of the brain; however, less is known about how the combination of these risk factors affects the vasculature. We recently reported that a moderate (60%) increase in plasma cholesterol blunts the recruitment of leukocytes and platelets in the cerebral microvessels elicited by hypertension. In this study, we examined whether larger increments in blood cholesterol (4-fold) exerts a similar modulating influence on the vasculature in the presence of hypertension. Apolipoprotein E-knockout mice with deoxycorticosterone acetate salt-induced hypertension were placed on a high-cholesterol diet and exhibited exaggerated leukocyte and platelet adhesion responses in cerebral microvessels. Intermittent feeding (every fourth day) with high-cholesterol diet yielded similar phenotypic changes in the vasculature. Once the mice were placed on high-cholesterol diet, 4 days on normal diet (ND) were needed to revert to a normal vascular phenotype. Angiotensin II type 1 receptors and reactive oxygen species seem to contribute to the vascular responses induced by hypercholesterolemia and hypertension. Our findings indicate that the combination of hypertension and large increases in plasma cholesterol concentration results in a severe, but reversible, inflammatory and thrombogenic phenotype in the cerebral microvasculature. PMID:24379186

Rodrigues, Stephen F; Almeida-Paula, Lidiana D; Granger, Daniel N

2014-04-01

170

Leukocyte Mitochondrial DNA Copy Number in Blood Is Not Associated with Major Depressive Disorder in Young Adults  

PubMed Central

Background Major depressive disorder (MDD) is the leading cause of disability worldwide, and has significant genetic predisposition. Mitochondria may have a role in MDD and so mitochondrial DNA (mtDNA) has been suggested as a possible biomarker for this disease. We aimed to test whether the mtDNA copy number of peripheral blood leukocytes is related to MDD in young adults. Methods A case-control study was conducted with 210 MDD patients and 217 healthy controls (HC). The mtDNA copy number was measured by quantitative polymerase chain reaction (qPCR) method. Depression severity was assessed by the Hamilton-17 Depression Rating Scale (HDRS-17). Results We found no significant differences in mtDNA copy number between MDD patients and HC, though the power analysis showed that our sample size has enough power to detect the difference. There were also no significant correlations between mtDNA copy number and the clinical characteristics (such as age, age of onset, episodes, Hamilton Depression Rating Scale (HDRS) score and Global Assessment of Function Scale (GAF) score) in MDD patients. Conclusion Our study suggests that leukocyte mtDNA copy number is unlikely to contribute to MDD, but it doesn’t mean that we can exclude the possibility of involvement of mitochondria in the disease. Further studies are required to elucidate whether mtDNA can be a biomarker of MDD. PMID:24809340

He, Ying; Tang, Jinsong; Li, Zongchang; Li, Hong; Liao, Yanhui; Tang, Yanqing; Tan, Liwen; Chen, Jindong; Xia, Kun; Chen, Xiaogang

2014-01-01

171

Quantitative analysis of the suppressors of cytokine signaling 1 and 3 in peripheral blood leukocytes of patients with multiple sclerosis.  

PubMed

Multiple sclerosis (MS) is an autoimmune disease characterized by a triad of inflammation, demyelination and gliosis. Because the suppressors of cytokine signaling (Socs) regulate the immune response, we quantified SOCS1 and SOCS3 transcription in peripheral blood leukocytes of patients with MS. SOCS1 transcription decreased significantly in MS patients compared with neurologically healthy persons (0.08±0.02 vs. 1.02±0.23; p=0.0001); while SOCS3 transcription increased in MS patients compared with controls (2.76±0.66 vs. 1.03±0.27; p=0.0008). Our results showed an imbalance of SOCS1 and SOCS3 transcription in MS patients, and a moderated negative correlation between them (Spearman's r=-0.57; p=0.0003). PMID:24951315

Sedeño-Monge, Virginia; Arcega-Revilla, Raúl; Rojas-Morales, Emmanuel; Santos-López, Gerardo; Perez-García, Juan Carlos; Sosa-Jurado, Francisca; Vallejo-Ruiz, Verónica; Solis-Morales, Casandra Lucrecia; Aguilar-Rosas, Salvador; Reyes-Leyva, Julio

2014-08-15

172

The effects of oil exposure on peripheral blood leukocytes and splenic melano-macrophage centers of Gulf of Mexico fishes.  

PubMed

In August and November 2010 we collected and examined peripheral blood and tissues from three species of Gulf of Mexico fish. Findings were compared to non-exposed control fish. The leukocyte counts of exposed alligator gar were not significantly different from controls, while exposed Gulf killifish and sea trout had significantly decreased lymphocyte counts. Liver ethoxyresorufin-O-deethylase (EROD) values from sea trout were significantly greater than control sea trout EROD values, suggesting poly aromatic hydrocarbon exposure. Splenic melano-macrophage centers (MMCs) from exposed sea trout and Gulf killifish showed a significant increase in number compared to non-exposed fish. Sea trout splenic MMCs were also significantly greater in size. These findings suggest that Gulf fish sampled were exposed to crude oil from the Macondo well and were in a lymphopenic or immuno-compromised state. PMID:24405733

Ali, Ahmad Omar; Hohn, Claudia; Allen, Peter J; Ford, Lorelei; Dail, Mary Beth; Pruett, Stephen; Petrie-Hanson, Lora

2014-02-15

173

Surface activation leukocyte markers and humoral factors in cord blood of newborns at risk of early infection.  

PubMed

Due to immaturity of both specific and non-specific immune mechanisms, neonates are at risk of serious infections. The risk group definition is vague, clinical signs are non-specific and common laboratory markers are not as useful as in later ages, especially due to delayed reactions. In an attempt to find early, sensitive and specific markers, we assessed a defined set of surface leukocyte markers and humoral factors in cord blood. Several differences were noted--children in the risk group had a higher proportion of CD19+/23+, CD16+/64+, CD45RO cells and higher levels of IL-6. We find it promising that already at birth there are notable signs of reaction to infection and that a follow-up of a set of infectious markers could be useful to identify the children in need of antibiotic treatment and for diminishing unnecessary treatment. PMID:18290545

Rozsíval, Pavel; Parízková, Eva; Vokurková, Doris; Buriánková, Bozena; Andrýs, Ctira

2007-01-01

174

Rho-Kinase Inhibition Reduces Early Microvascular Leukocyte Accumulation in the Rat Kidney following Ischemia-Reperfusion Injury: Roles of Nitric Oxide and Blood Flow  

Microsoft Academic Search

Aim: To study whether microvascular leukocyte accumulation after rat renal ischemia and reperfusion (IR) is decreased by Rho kinase inhibition, independently of effects upon nitric oxide (NO) and renal blood flow. Methods: Male Wistar rats were subjected to 60 min of ischemia by bilateral clamping and 60 min of reperfusion of the renal arteries, or a sham procedure. Haemodynamics were

Amanda M. G. Versteilen; Nick Blaauw; Francesco Di Maggio; A. B. Johan Groeneveld; Pieter Sipkema; René J. P. Musters; Geert-Jan Tangelder

2011-01-01

175

A METHOD FOR THE RAPID SEPARATION OF LEUKOCYTES AND NUCLEATED ERYTHROCYTES FROM BLOOD OR MARROW WITH A PHYTOHEMAGGLUTININ FROM RED BEANS (PHASEOLUS VULGARIS)  

Microsoft Academic Search

A TECHNICALLY simple and rapid method for separating living leukocytes and nucleated erythrocytes from whole blood or marrow with a high degree of efficiency, large net yield and negligible admixture with mature erythrocytes or other contaminants is needed for chemical, metabolic or cultural studies of these cells. The method presented in this paper describes a technic for accelerating the sedimentation

JONAH G. Li; EDWIN E. OSGOOD

176

PrPSc Is Not Detected in Peripheral Blood Leukocytes of Scrapie-Infected Sheep: Determining the Limit of Sensitivity by Immunohistochemistry  

Technology Transfer Automated Retrieval System (TEKTRAN)

Peripheral blood leukocytes (PBL) from scrapie-infected sheep were evaluated for the presence of PrPSc using dissociated retropharyngeal lymph node cells (DRLN) and immunohistochemistry (IHC). PrPSc positive cells were detected in 2.05% with a variance of .28% of 3,000,000DRLN cells but were not de...

177

[Frequency of different infectious agents persistence in mononuclear leukocytes of blood and synovial fluid in patients with rheumatoid arthritis].  

PubMed

The study of persistence in mononuclear leukocytes (ML) of blood and synovial fluid of 218 patients with rheumatoid arthritis (RA) Cytornegalovirus (CMV), the 1-st and 2-nd types of Herpes virus simplex (VH), Epstain-Barr virus (VEB), Mycoplasma arthritidis (Ma), Mycoplasma fermentans (Mf), Ureaplasma urealiticum (U), Chlamidia trachomatis (Ct), viruses of Hepatitis B and C was carry out by direct and indirect immunofruorescence, immunoenzymatic analysis and polymerase chain reaction. An increased frequency of contamination of blood ML with infectious agents in patients with RA was established (57,4% compared with 16,7% in control group). The following infectious agents were revieled more frequently: in ML of blood and synovial fluid the Ma (relatively 20,5% and 15,9%), Mf (15,6% and 13,2%), Ct (18,4% and 13,2%), VH (27,1% and 10,5%), VEB (12,7% and 5,3%) and CMV (11,2% and 7,9%). Types of frequency dynamics of ML contamination with these infectious agents in different time phases of RA were determined. PMID:16396287

Petrov, A V

2005-01-01

178

Complement Activation During Storage of Blood Under Normal Blood Bank Conditions. Effects of Proteinase Inhibitors and Leukocyte Depletion  

Microsoft Academic Search

ONG-TERM STORAGE at 4°C of whole blood and of L red blood cell components is a widely used routine procedure that has proven essential to meet the needs of modern medicine. The metabolism and the functional integrity of the cellular components of blood have been extensively studied during and after long-term Much less is known about variations of soluble plasma

Michael Schleuning; Michael Schmid-Haslbeck; Heike Utz; Marianne Jochum; Marcel Heim; Wolfgang Mempel; Wolfgang Wilmanns

1992-01-01

179

Cytogenetic observations in human peripheral blood leukocytes following in vitro exposure to THz radiation: a pilot study.  

PubMed

Emerging technologies are considering the possible use of Terahertz radiation in different fields ranging from telecommunications to biology and biomedicine. The study of the potential effects of Terahertz radiation on biological systems is therefore an important issue in order to safely develop a variety of applications. This paper describes a pilot study devoted to determine if Terahertz radiation could induce genotoxic effects in human peripheral blood leukocytes. For this purpose, human whole blood samples from healthy donors were exposed for 20 min to Terahertz radiation. Since, to our knowledge, this is the first study devoted to the evaluation of possible genotoxic effects of such radiation, different electromagnetic conditions were considered. In particular, the frequencies of 120 and 130 GHz were chosen: the first one was tested at a specific absorption rate (SAR) of 0.4 mW g-1, while the second one was tested at SAR levels of 0.24, 1.4, and 2 mW g-1. Chromosomal damage was evaluated by means of the cytokinesis block micronucleus technique, which also gives information on cell cycle kinetics. Moreover, human whole blood samples exposed to 130 GHz at SAR levels of 1.4 and 2 mW g-1 were also tested for primary DNA damage by applying the alkaline comet assay immediately after exposure. The results obtained indicate that THz exposure, in the explored electromagnetic conditions, is not able to induce either genotoxicity or alteration of cell cycle kinetics in human blood cells from healthy subjects. PMID:17351499

Zeni, O; Gallerano, G P; Perrotta, A; Romanò, M; Sannino, A; Sarti, M; D'Arienzo, M; Doria, A; Giovenale, E; Lai, A; Messina, G; Scarfì, M R

2007-04-01

180

Red Blood Cell Size Is Inversely Associated with Leukocyte Telomere Length in a Large Multi-Ethnic Population  

PubMed Central

Although mutations in the genes encoding either the protein or RNA component of telomerase have been found in patients with various blood disorders, the impact of telomere length on hematopoiesis is less well understood for subjects from the general population. Here we have measured telomere lengths of genomic DNA isolated from circulating leukocytes of 3157 subjects, ranging from 18 to 85 years of age, enrolled in a large multiethnic population based study, the Dallas Heart Study 2. Shorter telomere lengths are marginally associated with lower red blood cell counts in this cohort, but are significantly associated with larger mean red blood cell size (as measured by the MCV), increased red blood cell distribution width (RDW), higher hemoglobin levels and lower platelet counts, even after correction for age, gender and ethnicity (p-values of <0.0001, <0.0001, 0.0009 and 0.0016, respectively). In a multiple regression model we find that telomere length is a significant covariate of MCV (p?=?7.6×10?8), independent of age, ethnicity, BMI, current smoking, alcohol consumption, iron or homocysteine levels. The effect of telomere length on MCV variation is comparable to the effect of smoking or alcohol consumption and is more significant in older individuals (p?=?9.2×10?7 for >50 years vs. p?=?0.0006 for <50 years of age). To our knowledge, this is the first report of an association between telomere length and red cell size in a large urban US population and suggests a biologic mechanism for macrocytosis of aging. PMID:23226558

Kozlitina, Julia; Garcia, Christine Kim

2012-01-01

181

Degeneration and atrophy of the thymus of lethally irradiated dogs, rescued by transfusion of cryopreserved autologous blood leukocytes  

SciTech Connect

Dogs exposed to a fatal radiation dose of 12 Gy were rescued by transfusion of autologous blood leukocytes. A severe acute and long-lasting damage to the thymus was observed. The acute damage, as observed on the tenth day, consisted of a marked reduction in the number of lymphocytes, degeneration of Hassall's bodies, and hemorrhage. Long-term effects, observed several months after irradiation, were partial to total atrophy of the thymus. Regeneration, when it occurred, was limited to a few small isolated areas in which lymphopoiesis was supported by epithelial reticular cells. In contrast, the lymph nodes of all dogs had abundant cortical lymphopoiesis. The abundant hemopoiesis present in the marrow from the tenth day after irradiation until the end of the observation period should have provided sufficient circulating precursor cells to seed the thymus and regenerate the organ to the same extent as that observed in the other blood-forming organs. The impairment of lymphopoietic regeneration in the thymus seems to be due, therefore, to damage caused by irradiation on the specific stroma of the organ, which is not able to support such activity.

Calvo, W.; Fliedner, T.M.; Herbst, E.W.; Huegl, E.B.; Boedey, B.

1987-12-01

182

Leukocyte count affects expression of reference genes in canine whole blood samples  

PubMed Central

Background The dog is frequently used as a model for hematologic human diseases. In this study the suitability of nine potential reference genes for quantitative RT-PCR studies in canine whole blood was investigated. Findings The expression of these genes was measured in whole blood samples of 263 individual dogs, representing 73 different breeds and a group of 40 mixed breed dogs, categorized into healthy dogs and dogs with internal and hematological diseases, and dogs that underwent a surgical procedure. GeNorm analysis revealed that a combination of 5 to 6 of the most stably expressed genes constituted a stable normalizing factor. Evaluation of the expression revealed different ranking of reference genes in Normfinder and GeNorm. The disease category and the white blood cell count significantly affected reference gene expression. Conclusions The discrepancy between the ranking of reference genes in this study by Normfinder and Genorm can be explained by differences between the experimental groups such as "disease category" and "WBC count". This stresses the importance of assessing the expression stability of potential reference genes for gene experiments in canine whole blood anew for each specific experimental condition. PMID:21303565

2011-01-01

183

Effects of immunoglobulin binding on signal transduction in bovine polymorphonuclear neutrophils  

Technology Transfer Automated Retrieval System (TEKTRAN)

Immunoglobulins are major molecules that mediate humoral immune responses. Their functional effects on leukocytes are mediated by the cell surface receptors for the Fc domain of immunoglobulins (FcR). Ligation of FcR on human polymorphonuclear neutrophils (PMN) is capable of triggering a wide rang...

184

An extended convection diffusion model for red blood cell-enhanced transport of thrombocytes and leukocytes  

NASA Astrophysics Data System (ADS)

Transport phenomena of platelets and white blood cells (WBCs) are fundamental to the processes of vascular disease and thrombosis. Unfortunately, the dilute volume occupied by these cells is not amenable to fluid-continuum modeling, and yet the cell count is large enough that modeling each individual cell is impractical for most applications. The most feasible option is to treat them as dilute species governed by convection and diffusion; however, this is further complicated by the role of the red blood cell (RBC) phase on the transport of these cells. We therefore propose an extended convection-diffusion (ECD) model based on the diffusive balance of a fictitious field potential, ?, that accounts for the gradients of both the dilute phase and the local hematocrit. The ECD model was applied to the flow of blood in a tube and between parallel plates in which a profile for the RBC concentration field was imposed and the resulting platelet concentration field predicted. Compared to prevailing enhanced-diffusion models that dispersed the platelet concentration field, the ECD model was able to simulate a near-wall platelet excess, as observed experimentally. The extension of the ECD model depends only on the ability to prescribe the hematocrit distribution, and therefore may be applied to a wide variety of geometries to investigate platelet-mediated vascular disease and device-related thrombosis.

Hund, S. J.; Antaki, J. F.

2009-10-01

185

Selective Activation of Cannabinoid Receptor 2 in Leukocytes Suppresses Their Engagement of the Brain Endothelium and Protects the Blood-Brain Barrier  

PubMed Central

Cannabinoid receptor 2 (CB2) is highly expressed in immune cells and stimulation decreases inflammatory responses. We tested the idea that selective CB2 activation in human monocytes suppresses their ability to engage the brain endothelium and migrate across the blood-brain barrier (BBB), preventing consequent injury. Intravital videomicroscopy was used to quantify adhesion of leukocytes to cortical vessels in lipopolysaccharide-induced neuroinflammation, after injection of ex vivo CB2–activated leukocytes into mice; CB2 agonists markedly decreased adhesion of ex vivo labeled cells in vivo. In an in vitro BBB model, CB2 activation in monocytes largely attenuated adhesion to and migration across monolayers of primary human brain microvascular endothelial cells and diminished BBB damage. CB2 stimulation in monocytes down-regulated active forms of integrins, lymphocyte function-associated antigen 1 (LFA-1), and very late antigen 4 (VLA-4). Cells treated with CB2 agonists exhibited increased phosphorylation levels of inhibitory sites of the actin-binding proteins cofilin and VASP, which are upstream regulators of conformational integrin changes. Up-regulated by relevant stimuli, Rac1 and RhoA were suppressed by CB2 agonists in monocytes. CB2 stimulation decreased formation of lamellipodia, which play a key role in monocyte migration. These results indicate that selective CB2 activation in leukocytes decreases key steps in monocyte–BBB engagement, thus suppressing inflammatory leukocyte responses and preventing neuroinflammation. PMID:24055259

Rom, Slava; Zuluaga-Ramirez, Viviana; Dykstra, Holly; Reichenbach, Nancy L.; Pacher, Pal; Persidsky, Yuri

2014-01-01

186

Critical role of nitric oxide during the apoptosis of peripheral blood leukocytes from patients with AIDS.  

PubMed Central

BACKGROUND: Highly active antiretroviral therapies (HAART) increase the CD4(+) cell count, but complete normalization of this parameter has not been obtained in some patients. As oxidative stress plays an important role during human immunodeficiency virus type 1 (HIV-1)-associated dementia and lymphocyte apoptosis, we asked whether the nitric oxide (NO) pathway plays a role in the in vitro survival of peripheral blood mononuclear cells (PBMC) from HIV-1(+) patients and how it correlates with peripheral CD4(+) cell levels. MATERIALS AND METHODS: PBMC were isolated from patients with AIDS and assayed for apoptosis and proliferation in the presence of various chemicals, including agonists or antagonists of the NO pathway. Data were then compared with several in vivo parameters from the same patients. RESULTS: Apoptosis of PBMC in the presence of exogenous NO is significantly higher in patients with low peripheral CD4(+) cell levels than in patients with high CD4(+) cell numbers or seronegative individuals. In addition, endogenous NO inhibition rescues cells from apoptosis in AIDS patients with low circulating CD4(+) cell numbers and helps recovery of the T cell proliferative response. NO-mediated apoptosis does not require cGMP but involves peroxynitrite generation, PARP activation, and NAD(+) depletion. CONCLUSIONS: Taken together, the data suggest the involvement of NO during the apoptosis and functional impairment of lymphocytes in patients with AIDS. PMID:10666481

Mossalayi, M. D.; Becherel, P. A.; Debré, P.

1999-01-01

187

Systemic suppression of human peripheral blood phagocytic leukocytes after whole-body UVB irradiation.  

PubMed

We examined systemic effects of whole-body UVB irradiation on human peripheral blood phagocytes. We found that 24 h after a single erythemal dose of UVB radiation two phagocyte functions, adhesion and phagocytosis, were reduced by 50%. This functional suppression was accompanied by a significant decrease in the expression of complement receptors (CR1 and CR3) and IgG Fc receptors (FcRII and FcRIII). The greatest reduction (47%) was observed in CR3, which is important for both adhesion and phagocytosis. A kinetic analysis showed that both CR1 and CR3 levels started to decrease 15 min after the UVB exposure, reaching the lowest levels at 4.5- and 24-h time points, respectively. The down-modulation of CRs after whole-body UVB exposure was not due to a defective receptor synthesis or translocation from internal stores to plasma membrane because the maximal CR levels in stimulated cells were not affected by UVB. No change in the serum soluble ICAM-1 was detected after UVB, which rules out CD1 1b epitope masking by sICAM-1. UVB did not release low-receptor-density myeloid progenitor cells from storage pools into circulation. Interleukin 10, a mediator of UVB-induced immunosuppression, was unable to modulate CR expression in vitro. When seven suberythemal whole-body UVB exposures were given repeatedly within 2 weeks, a significant decrease in CR expression was seen, which was greatest after three irradiations. Our data suggest that an exposure to UVB has systemic effects in humans which, possibly due to the down-modulation of preexisting cell-surface receptors, suppress some important functions of circulating phagocytic cells. PMID:10331484

Leino, L; Saarinen, K; Kivistö, K; Koulu, L; Jansen, C T; Punnonen, K

1999-05-01

188

Peripheral blood leukocytes and serum nested polymerase chain reaction are complementary methods for monitoring active cytomegalovirus infection in transplant patients  

PubMed Central

BACKGROUND: Human cytomegalovirus is an important cause of morbidity and mortality in immunocompromised patients. Qualitative polymerase chain reaction (PCR) has proven to be a sensitive and effective technique in defining active cytomegalovirus infection, in addition to having low cost and being a useful test for situations in which there is no need for quantification. Real-time PCR has the advantage of quantification; however, the high cost of this methodology makes it impractical for routine use. OBJECTIVE: To apply a nested PCR assay to serum (sPCR) and to evaluate its efficiency to diagnose active cytomegalovirus infection compared with PCR of peripheral blood leukocytes (L-PCR). METHODS: Samples of 37 patients were prospectively evaluated. An internal control was created and applied to sPCR to exclude false-negative results. RESULTS: In total, 21 patients (57%) developed active cytomegalovirus infection. After analyzing the two methods for the diagnosis of active infection, higher sensitivity and negative predictive value of the L-PCR versus sPCR (100% versus 62%), and higher specificity and positive predictive value of sPCR versus L-PCR (81% versus 50% and 72%, respectively) were observed. Discordant results were observed in 11 patients who were L-PCR-positive but sPCR-negative for active cytomegalovirus infection, five of whom developed clinical symptoms of cytomegalovirus. Clinical symptoms were observed in 14 patients, 12 of whom were diagnosed with active infection by nested L-PCR (P=0.007) and seven by nested sPCR (P=0.02). Higher specificity and a positive predictive value for sPCR were observed. CONCLUSION: Nested L-PCR and sPCR were considered to be complementary methods for the diagnosis and management of symptomatic cytomegalovirus infection. PMID:24421834

Andrade, PD; Fioravanti, MT; Anjos, EBV; De Oliveira, C; Albuquerque, DM; Costa, SCB

2013-01-01

189

Comprehensive analysis of commercially available mouse antichicken monoclonal antibodies for cross-reactivity with peripheral blood leukocytes from commercial turkeys.  

PubMed

In the United States, turkey production contributes approximately $14.4 billion to the US economy; however, the number of reagents specifically developed to study the immune system of this economically important species is limited. To compensate for this, laboratories focused on the turkey system have each empirically tested various chicken-specific reagents for cross-reactivity with turkeys. The result is a patchwork of reports using different genetic lines and different ages, and in many cases, leading to inconsistent conclusions about the cross-reactivity of the reagents tested. In the current study, we investigated a large panel of commercially available monoclonal antibodies specific for chicken leukocyte markers for their ability to specifically recognize the turkey homolog of their respective ligand using 2 different genetic lines of commercial turkeys. The results of these studies identify 8 chicken-specific monoclonal antibodies (F21-21, F21-2, CT4, EP96, 3-298, AV7, c264, and AV6) as demonstrating strong evidence for cross-reactivity with turkey peripheral blood mononuclear cells from both commercial lines, 3 of which (F21-2, EP96, and c264), to our knowledge, have not previously been reported. In addition, characterization of the anti-CD8? monoclonal antibody 3-298 provides evidence that turkeys, like chickens, have a relatively high percentage of CD4CD8 double-positive T-cells in circulation and have at least 5 alleles of the CD8? gene. Collectively, the results from these experiments strengthen our understanding of the turkey immune system, its relative level of conservation with the chicken system, and adds to the list of reagents that can be reliably used to assess immune responses in commercial turkeys. PMID:22252352

Meyerhoff, R R; Ali, R A; Liu, K; Huang, G-Q; Koci, M D

2012-02-01

190

DNA extraction for short tandem repeat typing from mixed samples using anti-human leukocyte CD45 and ABO blood group antibodies.  

PubMed

DNA testing from mixed cell samples can be difficult to use successfully in criminal investigations. Here, we present a method for the extraction of DNA from mixed bloodstains involving plural contributors, after antibody-microbead captured cell separation. This method, together with the multiplex short tandem repeat typing presented, has proven highly successful in the recovery of DNA profiles corresponding to the ABO blood type. Methodological steps include magnetic separation using leukocyte specific CD45 antibody-coated microbeads and centrifugal separation of leukocyte agglutination by ABO antibody. The detection results of variable mixed ratio showed that the target DNA was detected accurately as low as 1:512 mixed ratio, regardless of the large amount of the background DNA present. The method presented here is applicable to PCR-based identification for various kinds of mixed samples. PMID:24680125

Yano, Shizue; Honda, Katsuya; Kaminiwa, Junko; Nishi, Takeki; Iwabuchi, Yayoi; Sugano, Yukiko; Kurosu, Akira; Suzuki, Yasuhito

2014-05-01

191

Interleukin-1 activation of vascular endothelium. Effects on procoagulant activity and leukocyte adhesion.  

PubMed Central

Interleukin-1 (IL-1), an inflammatory/immune mediator, acts directly and selectively on cultured human vascular endothelial cells to alter two important functional properties. First, IL-1 induces endothelial cell biosynthesis and surface expression of a tissue factor-like procoagulant activity. Second, IL-1 dramatically increases the adhesiveness of the endothelial cell surface for human peripheral blood polymorphonuclear leukocytes (6-42-fold increase) and monocytes (2-5-fold increase), as well as the related leukocyte cell lines HL-60 and U937. These IL-1 effects are concentration-dependent (maximum, 5-10 U/ml), time-dependent (peak 4-6 hours), and reversible. Cycloheximide and actinomycin D block these IL-1 actions on endothelium, which suggests the requirement for de novo protein synthesis. Human-monocyte-derived IL-1, cell-line--derived IL-1, and recombinant IL-1 exhibited comparable biologic activities in our assays, whereas two other mediators, IL-2 and immune interferon, were without effect. IL-1 stimulated procoagulant activity and leukocyte adhesion in human endothelial cells cultured from both umbilical veins and adult saphenous veins but not in other cultured cell types, including SV-40-transformed human endothelial cells and human dermal fibroblasts. Similar actions of IL-1 on vascular endothelium in vivo may contribute to the development of intravascular coagulation and enhanced leukocyte--vessel wall adhesion at sites of inflammation. Images Figure 2 PMID:3878084

Bevilacqua, M. P.; Pober, J. S.; Wheeler, M. E.; Cotran, R. S.; Gimbrone, M. A.

1985-01-01

192

Mononuclear Leukocyte Infiltrate in Extraplacental Membranes and Preterm Delivery  

PubMed Central

Large numbers of polymorphonuclear leukocytes in the amnion and chorion define histological chorioamnionitis (HCA), a condition linked to spontaneous preterm delivery (PTD). Less is known about placental patterns of mononuclear leukocyte (MNL) density and PTD. In this prospective study (1998–2004), women were sampled from 52 clinics in 5 Michigan communities and enrolled at 16–27 weeks’ gestation. HCA and MNL distributions in delivered placentas were evaluated microscopically in a subcohort (290 preterm, 823 term). Midpregnancy biomarkers from maternal blood (i.e., C-reactive protein (CRP), corticotropin-releasing hormone, and cytokines) were compared among term and PTD subjects grouped by presence/absence of HCA and high MNL density. A density of more than 10 MNLs per high-power field in the chorion of the membrane roll, referred to as MNL-CMR, was associated with medically indicated PTD (odds ratio = 2.2, 95% confidence interval: 1.3, 3.6) and spontaneous PTD (odds ratio = 2.5, 95% confidence interval: 1.7, 3.7). Associations persisted after removal of women with HCA-positive placentas, abruption, hypertensive disorders, or obesity. HCA-associated PTD showed higher CRP and cytokine levels. MNL-CMR-associated PTD showed higher CRP and corticotropin-releasing hormone levels. These data suggest that an MNL infiltrate in the chorion of the membrane roll marks PTD pathways that are distinct from HCA and not entirely explained by pregnancy complications. PMID:23429723

Holzman, Claudia; Senagore, Patricia K.; Wang, Jianling

2013-01-01

193

The alpha 4-integrin supports leukocyte rolling and adhesion in chronically inflamed postcapillary venules in vivo  

PubMed Central

A role for the alpha 4-integrin (alpha 4 beta 1 or alpha 4 beta 7), has been implicated in the recruitment of peripheral blood mononuclear cells (PBMCs) to sites of inflammation. However, the adhesive interactions (i.e., tethering, rolling, and adhesion) mediated by the alpha 4-integrin have not been characterized in vivo. The objective of this study was to establish a model wherein postcapillary venules were chronically inflamed, and then use intravital microscopy to identify the adhesive interactions mediated by the alpha 4-integrin in vivo. Between 4 and 20 d after immunization with Mycobacterium butyricum, animals developed a systemic vasculitis characterized by large increases in the numbers of rolling and adhering leukocytes within mesenteric venules. The selectins could only account for approximately 50% of the leukocyte rolling whereas the remaining cells rolled exclusively via the alpha 4-integrin. Anti-alpha 4 therapy also eliminated the increase in leukocyte adhesion observed in this model, whereas selectin therapies and an anti-CD18 (beta 2-integrin) monoclonal antibody (mAb) did not reduce adhesion. A serum against polymorphonuclear leukocytes (PMNs) was used to confirm that a significant proportion of rolling cells, and most of the adhering cells were PBMCs. Sequential treatment with anti-PMN serum and the anti-alpha 4 mAb demonstrated that alpha 4-dependent rolling was distinct from PMN rolling populations. Initial leukocyte tethering via the alpha 4- integrin could not be demonstrated in this model, whereas L-selectin did support leukocyte tethering. These data suggest that the alpha 4- integrin can mediate both rolling and adhesion in the multistep recruitment of PMBCs in vivo, and these interactions occur independently of the selectins and beta 2-integrins. PMID:8642310

1996-01-01

194

Hesperidin Displays Relevant Role in the Nutrigenomic Effect of Orange Juice on Blood Leukocytes in Human Volunteers: A Randomized Controlled Cross-Over Study  

PubMed Central

Background We previously showed, in healthy, middle-aged, moderately overweight men, that orange juice decreases diastolic blood pressure and significantly improves postprandial microvascular endothelial reactivity and that hesperidin could be causally linked to the observed beneficial effect of orange juice. The objective was to determine the effect of chronic consumption of orange juice on the gene expression profile of leukocytes in healthy volunteers and to assess to what extent hesperidin is involved in the effect of orange juice. Methodology/Principal Findings Volunteers were included in a randomized, controlled, crossover study. Throughout three 4-week periods, volunteers consumed daily: 500 ml orange juice, 500 ml control drink plus hesperidin or 500 ml control drink and placebo. Blood samplings were performed on 10 overnight-fasted subjects after the 4-week treatment period. Global gene expression profiles were determined using human whole genome cDNA microarrays. Both orange juice and hesperidin consumption significantly affected leukocyte gene expression. Orange juice consumption induced changes in expression of, 3,422 genes, while hesperidin intake modulated the expression of 1,819 genes. Between the orange juice and hesperidin consumption groups, 1,582 regulated genes were in common. Many of these genes are implicated in chemotaxis, adhesion, infiltration and lipid transport, which is suggestive of lower recruitment and infiltration of circulating cells to vascular wall and lower lipid accumulation. Conclusions This study shows that regular consumption of orange juice for 4 weeks alters leukocyte gene expression to an anti-inflammatory and anti-atherogenic profile, and hesperidin displays a relevant role in the genomic effect of this beverage. Trial Registration ClinicalTrials.gov NCT 00983086 PMID:22110589

Milenkovic, Dragan; Deval, Christiane; Dubray, Claude; Mazur, Andrzej; Morand, Christine

2011-01-01

195

Sour cherry (Prunus cerasus) seed extract increases heme oxygenase-1 expression and decreases proinflammatory signaling in peripheral blood human leukocytes from rheumatoid arthritis patients.  

PubMed

Sour cherry seed extract (SCE) was evaluated for its capacity to inhibit lipopolysaccharide-treated human peripheral blood T cells expressing tumor necrosis factor-alpha, and the chemokine interleukin-8. Both proteins are diagnostic biomarkers for inflammatory pathologies. Peripheral blood leukocytes from 11 rheumatoid arthritis (RA) patients and 8 healthy control subjects were co-cultured for 24h in lipopolysaccharide and the extract, then evaluated by flow cytometry for T cell activation and by enzyme-linked immunoassay for lymphocyte-associated heme oxygenase-1 (HO-1) expression. There was a dose-dependent decrease in expression of the immunophenotypes: CD3+TNF-?+, and CD3+IL8+ in cultures from RA patients to a greater extent than in cells from healthy participants. These results suggest that the extract may have a modulatory roll in RA and other inflammatory disorders via the induction of HO-1, thus abating oxidative stress and strengthening regulation of pro-inflammatory signaling pathways. PMID:24631368

Mahmoud, Fadia; Haines, David; Al-Awadhi, Rana; Dashti, Ali A; Al-Awadhi, Adel; Ibrahim, Basel; Al-Zayer, Bashayer; Juhasz, Bela; Tosaki, Arpad

2014-05-01

196

Force as a Facilitator of Integrin Conformational Changes during Leukocyte Arrest on Blood Vessels and Antigen-Presenting Cells  

Microsoft Academic Search

Integrins comprise a large family of cell-cell and cell-matrix adhesion receptors that rapidly modulate their adhesiveness. The arrest of leukocyte integrins on target vascular beds involves instantaneous conformational switches generating shear-resistant adhesions. Structural data suggest that these integrins are maintained in low-affinity conformations and must rapidly undergo conformational switches transduced via cytoplasmic changes (''inside-out'' signaling) and simultaneous ligand- induced rearrangements

Ronen Alon; Michael L. Dustin

2007-01-01

197

Enhanced Chemotactic and Phagocytic Activities of Leukocytes in Psoriasis Vulgaris  

Microsoft Academic Search

Leukocytes derived from the peripheral blood of peripheral patients demonstrated an enhanced chemotactic response compared with leukocytes from healthy subjects. No significant difference was detected between the chemotactic response of leukocytes from patients with minimal or no skin involvement and those from patients with extensive lesions. Psoriatic leukocytes also had a significantly higher capacity to engulf 125I labeled Shigella flexneri

A. Wahba; H. A. Cohen; M. Bar-Eli; R. Gallily

1978-01-01

198

Leukocyte and /sup 67/Ga-citrate dynamics in experimental subcutaneous Streptococcus faecalis infections  

SciTech Connect

The dynamics of white blood cell (WBC) and /sup 67/Ga-citrate accumulation were studied in rabbits with subcutaneous polyethylene chambers. Uninfected chamber fluid (CF) contained less than 1,000 WBCs/mm3, most of which were mononuclear. After /sup 67/Ga injection, radioactivity increased slowly in uninfected fluid, peaked between 24 and 48 hours, and then gradually decreased. /sup 67/Ga scans showed no uptake in excess of background levels around the uninfected chambers. After injection of Streptococcus faecalis directly into the chambers, bacterial concentrations initially decreased, increased by 4-24 hours, and then decreased slightly. WBCs began to increase 4 hours after infection due to influx of polymorphonuclear leukocytes. /sup 67/Ga localized in infected chambers before the increase in WBCs. Use of the subcutaneous chamber model could help elucidate the mechanism(s) of /sup 67/Ga accumulation at sites of inflammation.

Tight, R.R.; Siddiqui, A.R.

1981-07-01

199

Leukocyte and /sup 67/Ga-citrate dynamics in experimental subcutaneous Streptococcus faecalis infections. [Rabbits  

SciTech Connect

The dynamics of white blood cell (WBC) and /sup 67/Ga-citrate accumulation were studied in rabbits with subcutaneous polyethylene chambers. Uninfected chamber fluid (CF) contained <1000 WBCs/mm/sup 3/, most of which were mononuclear. After /sup 67/Ga injection, radioactivity increased slowly in uninfected fluid, peaked between 24 and 48 hours, and then gradually decreased. /sup 67/Ga scans showed no uptake in excess of background levels around the uninfected chambers. After injection of Streptococcus faecalis directly into the chambers, bacterial concentrations initially decreased, increased by 4 to 24 hours, and then decreased slightly. WBCs began to increase 4 hours after infection due to influx of polymorphonuclear leukocytes. /sup 67/Ga localized in infected chambers before the increase in WBCs. Use of the subcutaneous chamber model could help elucidate the mechanism(s) of /sup 67/Ga accumulation at sites of in flammation.

Tight, R.R.; Siddiqui, A.R.

1981-07-01

200

Label-free in vivo imaging of human leukocytes using two-photon excited endogenous fluorescence  

NASA Astrophysics Data System (ADS)

We demonstrate that two-photon excited endogenous fluorescence enables label-free morphological and functional imaging of various human blood cells. Specifically, we achieved distinctive morphological contrast to visualize morphology of important leukocytes, such as polymorphonuclear structure of granulocyte and mononuclear feature of agranulocyte, through the employment of the reduced nicotinamide adenine dinucleotide (NADH) fluorescence signals. In addition, NADH fluorescence images clearly reveal the morphological transformation process of neutrophils during disease-causing bacterial infection. Our findings also show that time-resolved NADH fluorescence can be potentially used for functional imaging of the phagocytosis of pathogens by leukocytes (neutrophils) in vivo. In particular, we found that free-to-bound NADH ratios measured in infected neutrophils increased significantly, which is consistent with a previous study that the energy consumed in the phagocytosis of neutrophils is mainly generated through the glycolysis pathway that leads to the accumulation of free NADH. Future work will focus on further developing and applying label-free imaging technology to investigate leukocyte-related diseases and disorders.

Zeng, Yan; Yan, Bo; Sun, Qiqi; Teh, Seng Khoon; Zhang, Wei; Wen, Zilong; Qu, Jianan Y.

2013-04-01

201

Leukocyte hydrogen peroxide production in a surgical wound in mice. The effects of an amide local anaesthetic  

Microsoft Academic Search

The oxygen metabolism of polymorphonuclear leukocytes (PMN) is of importance in local tissue repair processes. Amide local anaesthetics are commonly used to relieve surgical wound pain. The cellular effects of local anaesthetics in vivo is poorly described in the literature. However, interactions between amide local anaesthetics and the oxygen metabolism of leukocytes have been reported. To extend that knowledge, this

Anders S. Eriksson; Robert Sinclair

1996-01-01

202

Blood leukocyte microarrays to diagnose systemic onset juvenile idiopathic arthritis and follow the response to IL-1 blockade  

PubMed Central

Systemic onset juvenile idiopathic arthritis (SoJIA) represents up to 20% of juvenile idiopathic arthritis. We recently reported that interleukin (IL) 1 is an important mediator of this disease and that IL-1 blockade induces clinical remission. However, lack of specificity of the initial systemic manifestations leads to delays in diagnosis and initiation of therapy. To develop a specific diagnostic test, we analyzed leukocyte gene expression profiles of 44 pediatric SoJIA patients, 94 pediatric patients with acute viral and bacterial infections, 38 pediatric patients with systemic lupus erythematosus (SLE), 6 patients with PAPA syndrome, and 39 healthy children. Statistical group comparison and class prediction identified genes differentially expressed in SoJIA patients compared with healthy children. These genes, however, were also changed in patients with acute infections and SLE. An analysis of significance across all diagnostic groups identified 88 SoJIA-specific genes, 12 of which accurately classified an independent set of SoJIA patients with systemic disease. Transcripts that changed significantly in patients undergoing IL-1 blockade were also identified. Thus, leukocyte transcriptional signatures can be used to distinguish SoJIA from other febrile illnesses and to assess response to therapy. Availability of early diagnostic markers may allow prompt initiation of therapy and prevention of disabilities. PMID:17724127

Allantaz, Florence; Chaussabel, Damien; Stichweh, Dorothee; Bennett, Lynda; Allman, Windy; Mejias, Asuncion; Ardura, Monica; Chung, Wendy; Wise, Carol; Palucka, Karolina; Ramilo, Octavio; Punaro, Marilynn; Banchereau, Jacques; Pascual, Virginia

2007-01-01

203

Estradiol enhances leukocyte binding to tumor necrosis factor (TNF)-stimulated endothelial cells via an increase in TNF-induced adhesion molecules E-selectin, intercellular adhesion molecule type 1, and vascular cell adhesion molecule type 1.  

PubMed Central

Adhesion of leukocytes to endothelial cells is a critical step in the development of acute and chronic inflammatory lesions. We report here that estradiol treatment of cultured human umbilical vein endothelial cells stimulated up to a twofold increase in TNF-induced adhesion of both polymorphonuclear leukocytes and PMA-activated peripheral blood mononuclear cells. This effect was more evident (threefold increase) when endothelial cells were cultured on the basement membrane glycoprotein laminin. Progesterone, but not testosterone, had a similar stimulatory effect. Estradiol also promoted a slight increase in interferon gamma-stimulated endothelial cell adherence for peripheral blood mononuclear cells, but no effect of estradiol was observed when adhesion of leukocytes to endothelial cells was stimulated with IL-1 or IL-4. The estradiol-induced increase in leukocyte binding to human umbilical vein endothelial cells was partially blocked by antibodies to the adhesion molecules E-selectin, intercellular adhesion molecule type 1 (ICAM-1), and vascular cell adhesion molecule type 1 (VCAM-1). Indirect immunofluorescence techniques showed that estradiol produces an increase in TNF-induced cell surface expression of these molecules. Northern blot analysis demonstrated a transient increase in TNF-induced expression of mRNA for E-selectin, ICAM-1, and VCAM-1 in endothelial cells treated with estradiol. Our data demonstrate that estradiol has important regulatory functions in promoting leukocyte-endothelial cell interactions that might contribute to the observed predominance in females of some autoimmune inflammatory diseases. Images PMID:7506711

Cid, M C; Kleinman, H K; Grant, D S; Schnaper, H W; Fauci, A S; Hoffman, G S

1994-01-01

204

Effect of infection with BHV-1 on peripheral blood leukocytes and lymphocyte subpopulations in calves with subclinical BVD.  

PubMed

Bovine viral diarrhea virus (BVDV) and bovine herpesvirus-1 (BHV-1) are important cattle pathogens that induce a broad immunosuppression on cell-mediated immune response on its own participating in the bovine respiratory disease complex (BRDC). The aim of our study was to evaluate the quantitative changes in immunocompetent cells in healthy calves and calves with subclinical bovine viral diarrhea (BVD), both inoculated with BHV-1. Total leukocyte counts exhibited changes mainly in neutrophils and lymphocytes that can contribute to the BVDV immunosuppression, thus accounting for some of the intergroup differences. Monocytes did not display numerical changes in either group. Regarding lymphocyte subpopulations, even though CD4+ T lymphocytes and B cells were depleted around 4 dpi in both infected groups, the main difference observed between both groups was in CD8+ T cells which displayed an earlier depletion in BVDV inoculated calves that can promote a greater BHV-1 dissemination, thus aggravating the course of the disease. PMID:23541923

Molina, V; Risalde, M A; Sánchez-Cordón, P J; Pedrera, M; Romero-Palomo, F; Luzzago, C; Gómez-Villamandos, J C

2013-08-01

205

Biocompatibility of Cellulosic and Synthetic Membranes Assessed by Leukocyte Activation  

Microsoft Academic Search

Background\\/Aims: The contact of blood with artificial surfaces may activate blood leukocytes and platelets and initiate the leukocyte inflammatory response. We have investigated the effect of a hemodialysis (HD) with a cellulosic- and a synthetic-based membrane on circulating leukocyte activation. Methods: Samples were obtained from patients with ESRD at baseline, and at 15 and 120 min of a hemodialysis session

Maria Rosa Hernández; Ana Maria Galán; Aleix Cases; Jose Lopez-Pedret; Arturo Pereira; Raul Tonda; Jordi Bozzo; Gines Escolar; Antonio Ordinas

2004-01-01

206

Modification of radiation-induced DNA double strand break repair pathways by chemicals extracted from Podophyllum hexandrum: an in vitro study in human blood leukocytes.  

PubMed

Radiation exposure is a serious threat to biomolecules, particularly DNA, proteins and lipids. Various exogenous substances have been reported to protect these biomolecules. In this study we explored the effect of pre-treatment with G-002M, a mixture of three active derivatives isolated from the rhizomes of Podophyllum hexandrum, on DNA damage response in irradiated human blood leukocytes. Blood was collected from healthy male volunteers, preincubated with G-002M and then irradiated with various doses of radiation. Samples were analyzed using flow cytometry to quantify DNA double strand break (DSB) biomarkers including ?-H2AX, P53BP1 and levels of ligase IV. Blood samples were irradiated in vitro and processed to determine time and dose-dependent kinetics. Semiquantitative RT-PCR was performed at various time points to measure gene expression of DNA-PKcs, Ku80, ATM, and 53BP1; each of these genes is involved in DNA repair signaling. Pre-treatment of blood with G-002M resulted in reduction of ?-H2AX and P53BP1 biomarkers levels and elevated ligase IV levels relative to non-G-002M-treated irradiated cells. These results confirm suppression in radiation-induced DNA DSBs. Samples pre-treated with G-002M and then irradiated also showed significant up-regulation of DNA-PKcs and Ku80 and downregulation of ATM and 53BP1 gene expressions, suggesting that G-002M plays a protective role against DNA damage. The protective effect of G-002M may be due to its ability to scavange radiation-induced free radicals or assist in DNA repair. Further studies are needed to decipher the role of G-002M on signaling molecules involved in radiation-induced DNA damage repair pathways. PMID:24500925

Srivastava, Nitya N; Shukla, Sandeep K; Yashavarddhan, M H; Devi, Memita; Tripathi, Rajendra P; Gupta, Manju L

2014-06-01

207

Cytokine profiles of cord and adult blood leukocytes: differences in expression are due to differences in expression and activation of transcription factors  

PubMed Central

Background Stem cell transplantation as therapy for hematological disorders is often hampered by severe graft-versus-host-disease. This may be reduced by umbilical cord blood transplantation, an effect that has been attributed to qualitative differences between neonatal and adult T cells. We compared levels of secreted proteins and cytokine mRNA induced in cord blood leukocytes (CBL) and adult blood leukocytes (ABL) by various stimuli. Results While interleukin-2 (IL-2) levels were similar in CBL and ABL, there was less induction of the Th1 cytokine interferon-? in CBL. Production of the Th2 cytokines IL-4, IL-5, and IL-13 and the hematopoietic cytokine IL-3 was much lower in CBL versus ABL after T-cell receptor-mediated stimulation, whereas production of GM-CSF was comparable in the 2 cell types. The lower levels of Th1 and Th2 cytokines were maintained in CBL during a 4-day time-course study, while after 12 hours IL-3 and GM-CSF reached in CBL levels similar to those in ABL. For all cytokines except IFN?, the IC50 values for inhibition by cyclosporin A were similar in ABL and CBL. In contrast, there was less expression and activation of transcription factors in CBL. Activation of NF-?B by TPA/ionomycin was detected in ABL but not CBL. Furthermore, there was less expression of the Th subset-specific transcription factors T-bet and c-maf in CBL versus ABL, whereas GATA-3 expression was similar. Expression of T-bet and c-maf correlated with expression of the Th1 and Th2 cytokines, respectively. Time course experiments revealed that T-bet expression was stimulated in both cell types, whereas c-maf and GATA-3 were induced only in ABL. Conclusion The diminished capability of CBL to synthesize cytokines is probably due to decreased activation of NF-?B, whereas differences in Th subsets are due to differences in regulation of Th lineage-specific transcriptions factors. We propose that the reduced incidence and severity of GvHD after allogeneic transplantation of umbilical CB cells is due to lesser activation of specific transcription factors and a subsequent reduction in production of certain cytokines. PMID:17764543

Nitsche, Andreas; Zhang, Meixia; Clauss, Theresa; Siegert, Wolfgang; Brune, Kay; Pahl, Andreas

2007-01-01

208

Leukocyte telomeres are longer in African Americans than in whites: the National Heart, Lung, and Blood Institute Family Heart Study and the Bogalusa Heart Study  

PubMed Central

Leukocyte telomere length (LTL) is ostensibly a bio-indicator of human aging. Here we report that African Americans have longer LTL than whites. We studied cross-sectionally 2453 individuals from the National Heart, Lung, and Blood Institute (NHLBI) Family Heart Study (age = 30–93 years) and the Bogalusa Heart Study (age = 19–37 years), comprising 1742 whites and 711 African Americans. We measured LTL by Southern blots of the terminal restriction fragments length. In 234 participants, telomere repeats were also measured by quantitative polymerase chain reaction (qPCR). Adjusted for age and body mass index (BMI), the respective leukocyte telomere lengths (mean ± SEM) were considerably longer in African Americans than in whites both in the Family Heart Study (7.004 ± 0.033 kb vs. 6.735 ± 0.024 kb, p < 0.0001) and the Bogalusa Heart Study (7.923 ± 0.063 kb vs. 7.296 ± 0.039 kb, p < 0.0001). We confirmed the racial effect on LTL by qPCR (3.038 ± 0.565 T/S units for African Americans vs. 2.714 ± 0.487 T/S units for whites, p < 0.001). Cross-sectionally, sex- and BMI-adjusted LTL became shorter with age (range 19–93 years) at a steeper slope in African Americans than in whites (0.029 kb year?1 vs. 0.020 kb year?1, respectively, p = 0.0001). We suggest that racial difference in LTL arises from a host of interacting biological factors, including replication rates of hematopoietic stem cells. PMID:18462274

Hunt, Steven C; Chen, Wei; Gardner, Jeffrey P; Kimura, Masayuki; Srinivasan, Sathanur R; Eckfeldt, John H; Berenson, Gerald S; Aviv, Abraham

2008-01-01

209

Expression of the cell adhesion molecules on leukocytes that demarginate during acute maximal exercise.  

PubMed

The pulmonary vascular bed is an important reservoir for the marginated pool of leukocytes that can be mobilized by exercise or catecholamines. This study was designed to determine the phenotypic characteristics of leukocytes that are mobilized into the circulation during exercise. Twenty healthy volunteers performed incremental exercise to exhaustion [maximal O2 consumption (VO2 max)] on a cycle ergometer. Blood was collected at baseline, at 3-min intervals during exercise, at VO2 max, and 30 min after exercise. Total white cell, polymorphonuclear leukocyte (PMN), and lymphocyte counts increased with exercise to VO2 max (P < 0.05). Flow cytometric analysis showed that the mean fluorescence intensity of L-selectin on PMN (from 14.9 +/- 1 at baseline to 9.5 +/- 1.6 at VO2 max, P < 0.05) and lymphocytes (from 11.7 +/- 1.2 at baseline to 8 +/- 0.8 at VO2 max, P < 0.05) decreased with exercise. Mean fluorescence intensity of CD11b on PMN increased with exercise (from 10.2 +/- 0.6 at baseline to 25 +/- 2.5 at VO2 max, P < 0.002) but remained unchanged on lymphocytes. Myeloperoxidase levels in PMN did not change with exercise. In vitro studies showed that neither catecholamines nor plasma collected at VO2 max during exercise changed leukocyte L-selectin or CD11b levels. We conclude that PMN released from the marginated pool during exercise express low levels of L-selectin and high levels of CD11b. PMID:10066712

van Eeden, S F; Granton, J; Hards, J M; Moore, B; Hogg, J C

1999-03-01

210

Biosynthesis of eoxin C4 by porcine leukocytes.  

PubMed

Human 15-lipoxygenase-1 (LO) possesses mainly 15-lipoxygenase activity whereas the animal ortholog 12/15-LO possesses mainly 12-lipoxygenase activity. These findings have raised the question if studies on animals can predict the function of 15-LO-1 in human. In this study we have characterized the arachidonic acid metabolites formed by porcine 12/15-LO. Mini pigs were infected with a parasite to increase the number of blood eosinophils, which highly express 12/15-LO. Isolated porcine polymorphonuclear leukocytes (PMNL) were incubated with arachidonic acid and the produced metabolites were analysed with HPLC and mass spectrometry (MS). The cells were found to produce 15-hydroxyeicosatetraenoic acid (HETE) and 12-HETE at a ratio of 1:5. Furthermore 8,15-dihydroxyeicosatetraenoic acids (DiHETEs) and 14,15-DiHETE were formed. Based on HPLC, UV-spectroscopy and MS analysis it was found that porcine PMNL also produced eoxin (EX) C4. These results demonstrate that although porcine 12/15-LO possesses primarily 12-lipoxygenase activity, the enzyme can catalyse the formation of EXC(4). PMID:22921794

Brunnström, Åsa; Backman, Linda; Tryselius, Ylva; Claesson, Hans-Erik

2012-01-01

211

Alterations in leukocyte oxidative metabolism in cigarette smokers.  

PubMed

The polymorphonuclear leukocyte (PMN) may play an important role in the pathogenesis of lung disease associated with cigarette smoking. To investigate its potential for oxidant-mediated lung injury in cigarette smokers, we studied PMN oxidative metabolism in asymptomatic cigarette smokers and nonsmoking control subjects. We found a marked increase in oxidant release in a group of cigarette smokers. After stimulation by phorbol myristate acetate, release of superoxide anion (O-2) by PMN in smokers with white blood counts (WBC) greater than 9,000 was 50% greater than in nonsmokers with similar WBC or smokers and nonsmokers with WBC less than 9,000. Abstinence from smoking did not affect the alterations in O-2 release nor did a serum factor appear responsible. The changes appeared to be part of a generalized increase in oxidative metabolism, as there was greater oxidation of glucose (1-14C) and chemiluminescence by PMN from smokers with WBC greater than 9,000. A further estimate of lung oxidant load was determined by evaluating the marginated pool of PMN. Smokers with WBC greater than 9,000 showed a 70% increase in WBC after epinephrine, and PMN oxidative metabolism remained increased in this group. This study demonstrates that cigarette smokers with elevated WBC have increased release of potentially toxic oxygen metabolites. These cigarette smokers also demonstrated increased oxidant release from the marginated PMN pool. Because leukocyte-generated oxygen metabolites are highly reactive and can cause tissue injury, these findings may have important implications in the pathogenesis of smoking-related lung disease. PMID:6295222

Ludwig, P W; Hoidal, J R

1982-12-01

212

Detection of CFTR protein in human leukocytes by flow cytometry.  

PubMed

Leukocytes have previously been shown to express detectable levels of the protein cystic fibrosis transmembrane conductance regulator (CFTR). This study aims to evaluate the application of flow cytometric (FC) analysis to detect CFTR expression, and changes thereof, in these cells. Aliquots (200 ?L) of peripheral whole blood from 12 healthy control volunteers (CTRLs), 12 carriers of a CFTR mutation (CFC), and 40 patients with cystic fibrosis (CF) carrying various combinations of CFTR mutations were incubated with specific fluorescent probes recognizing CFTR protein expressed on the plasma membrane of leukocytes. FC was applied to analyze CFTR expression in monocytes, lymphocytes, and polymorphonuclear (PMN) cells. CFTR protein was detected in monocytes and lymphocytes, whereas inconclusive results were obtained from the analysis of PMN cells. Mean fluorescence intensity (MFI) ratio value and %CFTR-positive cells above a selected threshold were the two parameters selected to quantify CFTR expression in cells. Lowest variability and the highest reproducibility were obtained when analyzing monocytes. ANOVA results indicated that both parameters were able to discriminate monocytes of healthy controls and CF individuals according to CFTR mutation classes with high accuracy. Significantly increased MFI ratio values were recorded in CFTR-defective cells that were also able to improve CFTR function after ex vivo treatment with PTC124 (Ataluren), an investigative drug designed to permit the ribosome to read through nonsense CFTR mutations. The method described is minimally invasive and may be used in the monitoring of responses to drugs whose efficacy can depend on increased CFTR protein expression levels. © 2014 International Society for Advancement of Cytometry. PMID:24623386

Johansson, Jan; Vezzalini, Marzia; Verzè, Genny; Caldrer, Sara; Bolognin, Silvia; Buffelli, Mario; Bellisola, Giuseppe; Tridello, Gloria; Assael, Baroukh Maurice; Melotti, Paola; Sorio, Claudio

2014-07-01

213

Improved chemotactic ability of neonatal polymorphonuclear cells induced by mild membrane rigidification.  

PubMed

Membrane lipid fluidity of peripheral blood polymorphonuclear cells (PMNs) of 24 newborn infants, 2-4 days after birth, was determined by steady-state fluorescence polarization with 1,6-diphenyl 1,3,5-hexatriene (DPH) as a probe and compared with that of PMNs from 23 adults. Measurements with intact cells, which correspond to all cellular lipid domains, did not display any statistically significant difference between PMNs of the two groups. However, application of bixinoyl glucosamine, a membrane-impermeable fluorescence quencher, revealed that the PMN plasma membrane of the newborn is about 23% more fluid than that of the adult. Total cholesterol-to-phospholipid ratio of newborn PMNs was found to be lower by about 10% than that of the adult, which could account for the difference in their plasma membrane fluidity. The possible implication of this finding for the deficit in chemotactic ability of leukocytes from newborns was tested with neonatal PMNs that have incorporated cholesteryl hemisuccinate (CHS), an efficient plasma membrane rigidifier. In all neonatal PMNs tested a mild incorporation of CHS (0.5-1 min incubation in 50 micrograms/ml dispersion) caused a significant improvement in their net chemotaxis, from an average value of 28 +/- 7 to 43 +/- 11. Longer incubations with CHS caused a gradual decrease in chemotactic ability that approached the basal level after about 5 min incubation. The net chemotaxis in adult PMNs was significantly higher than that of neonatal PMNs (72 +/- 13) and was gradually inhibited by incorporation of CHS without any initial augmentation. Based on these results it was estimated that about 27% of the chemotactic deficit of neonatal PMNs is mediated by their immature fluid membrane. PMID:1564397

Wolach, B; Ben Dor, M; Chomsky, O; Gavrieli, R; Shinitzky, M

1992-04-01

214

Cloning and expression of recombinant equine interleukin-3 and its effect on sulfidoleukotriene and cytokine production by equine peripheral blood leukocytes.  

PubMed

Interleukin-3 is a growth and differentiation factor for various hematopoietic cells. IL-3 also enhances stimulus-dependent release of mediators and cytokine production by mature basophils. Function of IL-3 has not been studied in horses because of lack of horse-specific reagents. Our aim was to produce recombinant equine IL-3 and test its effect on sulfidoleukotriene and cytokine production by equine peripheral blood leukocytes (PBL). Equine IL-3 was cloned, expressed in E. coli and purified. PBL of 19 healthy and 20 insect bite hypersensitivity (IBH)-affected horses were stimulated with Culicoides nubeculosus extract with or without IL-3. Sulfidoleukotriene (sLT) production was measured in supernatants by ELISA and mRNA expression of IL-4, IL-13 and thymic stromal lymphopoietin (TSLP) assessed in cell lysate by quantitative real-time PCR. Recombinant equine IL-3 (req-IL-3) had a dose dependent effect on sLT production by stimulated equine PBL and significantly increased IL-4, IL-13 and TSLP expression compared to non-primed cells. IL-3 priming significantly increased Culicoides-induced sLT production in IBH-affected but not in non-affected horses and was particularly effective in young IBH-affected horses (?3 years). A functionally active recombinant equine IL-3 has been produced which will be useful for future immunological studies in horses. It will also allow improving the sensitivity of cellular in vitro tests for allergy diagnosis in horses. PMID:25530476

Janda, Jozef; Lehmann, Melissa; Luttmann, Werner; Marti, Eliane

2015-02-15

215

The effects of stress on the enzymes of peripheral leukocytes  

NASA Technical Reports Server (NTRS)

Previous work showed an early response of rabbit and human leukocyte enzymes to the stress of bacterial infection. Since these represented a mixed population of leukocytes and since polymorphonuclear leukocytes (PMN) increased in these preparations, it was necessary to establish whether the observed increase in lactate dehydrenase (LDH) and protein was the result of an increase in any one particular cell type or in all cells. The need for the development of a simple reproducible method for the differential separation of peripheral leukocytes for the furtherance of our own studies was apparent. It was also becoming increasingly apparent that morphologically similar cells, such as small lymphocytes (L) and macrophages, were capable of different biological functions. A dextran gradient centrifugation method was developed which has provided an easily reproducible technique for separating L from PMN. During the course of this work, in which over 250 rabbits were examined, the pattern of daily leukocyte protein and enzyme variation became increasingly more apparent. This information could have some impact on future work with leukocyte enzymes, by our group and by other workers. The differences in normal protein and enzyme levels maintained by some individuals, and some inbred strains, were evaluated and reported separately. It has been shown that one type of leukocyte may react more to a given stress than other leukocytes.

Leise, E. M.; Gray, I.

1973-01-01

216

Roles of p38 Mitogen-Activated Protein Kinase, NF B, and Protein Kinase C in Proinflammatory Cytokine mRNA Expression by Human Peripheral Blood Leukocytes, Monocytes, and Neutrophils in Response to Anaplasma phagocytophila  

Microsoft Academic Search

Anaplasma phagocytophila, an obligately intracellular bacterium of granulocytes, causes human granulocytic ehrlichiosis. Within 2 h after addition of A. phagocytophila, interleukin-1 (IL-1), tumor necrosis factor alpha (TNF-), and IL-6 mRNAs are induced in human peripheral blood leukocytes (PBLs) or monocytes in vitro. However, neutrophils generate only IL-1 mRNA. In the present study, signaling pathways for induction of these three cytokines

Hyung-Yong Kim; Yasuko Rikihisa

2002-01-01

217

Measurement and characterization of membrane-bound and soluble epoxide hydrolase activities in resting mononuclear leukocytes from human blood.  

PubMed

Membrane-bound and soluble epoxide hydrolase activities in the mononuclear cell fraction from human blood have been characterized using cis- and trans-stilbene oxides as substrates, respectively. Because of the low activities in these cells, it was necessary to modify assay procedures developed for rat and mouse liver in the following ways: (a) the substrates were relatively highly labeled (2 Ci/mmol) and carefully purified; (b) the incubation time was extended to 45 to 60 min, during which period the activities were linear; (c) as many as 6 million cells were used for a single assay, which was also within the linear range of the procedure. The membrane-bound epoxide hydrolase characterized in this manner has an apparent Vmax of 7.26 pmol product formed per min per 10(7) cells and an apparent Km of 9.96 microM. The pH optimum was observed to be around 9.8. The dependence of this activity on temperature showed its optimum at 40 degrees. The soluble epoxide hydrolase activity has an apparent Vmax of about 8.26 pmol product formed per min per 10(7) cells, an apparent Km of 1.63 microM, a pH optimum of 6.2 to 6.8, and a temperature optimum at 60 degrees. Using these techniques, these activities have also been determined in other blood components, i.e., lymphocytes, monocytes, granulocytes, erythrocytes, platelets, and plasma. Lymphocytes account for most of the epoxide hydrolase activity towards cis-stilbene oxide, and all of the activity towards trans-stilbene oxide is in the human mononuclear cell fractions. Different substances known to affect rodent epoxide hydrolases were tested for their effects on the human mononuclear blood cell activities. Interestingly, 1,1,1-trichloropropane 2,3-epoxide, a potent inhibitor of liver microsomal epoxide hydrolase in different species including rat, mouse, and human, had little or no effect on the membrane-bound activity measured here. However, cyclohexene oxide inhibits this membrane-bound activity 60%. The soluble epoxide hydrolase is inhibited to 90% of control levels by chalcone epoxide. The membrane-bound and soluble epoxide hydrolase activities determined in 27 subjects varied from 8.2 to 18.5 and from 3.5 to 17.0 pmol product formed per min per 10(7) cells, respectively. The mean coefficient of intraindividual variation, determined with three subjects measured four times each over the course of 18 days, was approximately 10% for both enzyme activities. PMID:6744285

Seidegård, J; DePierre, J W; Pero, R W

1984-09-01

218

Assessing immune function by profiling cytokine release from stimulated blood leukocytes and the risk of infection in rheumatoid arthritis.  

PubMed

Persons with rheumatoid arthritis (RA) suffer a high burden of infections, but currently no biomarkers are available to identify individuals at greatest risk. A prospective longitudinal study was therefore conducted to determine the association between the responsiveness of ex vivo cytokine production and 6-month risk of infections. Infections were identified by billing codes and validated by medical record review. At baseline, the release of 17 cytokines by peripheral blood mononuclear cells in response to stimulation, or media alone, was measured using multiplexed cytokine analysis. Production of IL-2, IL-8, IL-10, IL-17, TNF-?, IFN-?, and GM-CSF, induced by various conditions, was significantly associated with the occurrence of infections. A multivariable prediction model based on these data provided new information on the risk of infection beyond standard assessments of disease activity, severity, and treatment. Future studies could utilize this information to devise new biomarkers for the prediction of infection in patients with RA. PMID:21703930

Krause, Megan L; Davis, John M; Knutson, Keith L; Strausbauch, Michael A; Strausbach, Michael A; Crowson, Cynthia S; Therneau, Terry M; Wettstein, Peter J; Matteson, Eric L; Gabriel, Sherine E

2011-10-01

219

Determination of acid alpha-naphthyl acetate esterase enzyme activity in peripheral blood leukocytes of gazelles (Gazella subgutturosa).  

PubMed

We examined gazelle peripheral blood leucocytes using the alpha-Naphthyl acetate esterase (ANAE) staining technique (pH 5.8). Our purpose was to determine the percentage of ANAE positive lymphocytes. The proportion of ANAE positive T-lymphocytes was 72%. T-lymphocytes showed an ANAE positive reaction, but eosinophilic granulocytes and monocytes also showed a positive reaction. By contrast, no reaction was detected in B-lymphocytes, neutrophil granulocytes or platelets. The reaction observed in T-lymphocytes was a red-brown coloration, usually 1-2 granules, but enough granules to fill the cytoplasm were detected rarely. As a result of ANAE enzyme staining, we concluded that the staining technique can be used as a cytochemical marker for gazelle T-lymphocytes. PMID:19085516

Altunay, H; Harem, I S; Harem, M K; Asti, R N; Kurtdede, N

2008-12-01

220

A melanoma helper peptide vaccine increases Th1 cytokine production by leukocytes in peripheral blood and immunized lymph nodes  

PubMed Central

Background Cancers produce soluble and cell-associated molecules that can suppress or alter antitumor immunity. Preclinical studies suggest the disease burden may alter the cytokine profile of helper T cell responses to cancer antigens. We studied cytokine production by helper T cells responding to vaccination with 6 melanoma helper peptides (6MHP) in blood and lymph nodes. Methods Twenty-three patients with stage IIIB-IV melanoma received a 6MHP vaccine. Antigen-reactive T cells from blood and draining lymph nodes were cultured, exposed to antigen, and then supernatants (days 2 and 5) were assayed for Th1 and Th2 cytokines. Results from 4 time points were compared to pre-vaccine levels. Results Cytokine responses to vaccinating peptides were observed in 83% of patients. Th1 favoring responses were most common (17 of 19 responders). The most abundant cytokines produced were IFN-? and IL-5 in the PBMC’s. IL-2 responses predominated in cells obtained from draining lymph nodes in 2-day culture but not in 5-day cultures. Patients with clinically measurable disease produced similar levels of total cytokine and similar degree of Th1 polarization as patients with no evidence of disease (NED). Conclusions The MHC class II-associated peptides used in this study induced helper T cells with a Th1-biased cytokine response in both PBMC and sentinel immunized nodes. Most patients can mount a Th1 dominant response to these peptides. Future studies are needed to test newer vaccine adjuvants in combination with these peptides. Trial registration CDR0000378171, Clinicaltrials: NCT00089219. PMID:25126421

2014-01-01

221

Gamma interferon reverses inhibition of leukocyte bactericidal activity by a 25-kilodalton fraction from Mycobacterium tuberculosis.  

PubMed Central

In this study we examined the effects of Mycobacterium tuberculosis cell extracts on the phagocytic activity of polymorphonuclear leukocytes and cultured peripheral blood monocytes. M. tuberculosis cell extracts were fractionated on Sephacryl S-200 columns, and a 25-kilodalton glycolipoprotein was shown to inhibit the intracellular killing ability of these leukocytes but had no effect on their phagocytic potential. This same fraction inhibited fusion of phagosomes with lysosomes, as assessed by noting the transfer of acridine orange from lysosomes to phagosomes. This fraction was shown to have a maximal inhibitory effect when it was in the form of an intact carbohydrate-lipid-protein complex. Gamma interferon (IFN-gamma), but not IFN-alpha, reversed the inhibitory effect of the mycobacterial component on bactericidal activity and on fusion of phagosomes and lysosomes. Thus, this 25-kilodalton fraction of M. tuberculosis cell extract may be important in protecting organisms against phagocytic degradation, an effect which can be reversed by IFN-gamma. PMID:3117692

Wadee, A A; Cohen, J D; Rabson, A R

1987-01-01

222

Effect of intravenously injected killed pneumococci on leukocytes, complement, and phagocytosis in rabbits.  

PubMed Central

A pneumococcal infection may be lethal in the absence of overwhelming pulmonary involvement, and death may occur even after the organisms have been killed with antibiotics. The mechanism of death is not understood but may be related to circulating pneumococcal products. For investigating the effects of nonviable pneumococci on several host defense mechanisms, rabbits were injected intravenously with 4 X 10(8) colony-forming units of killed sonified type 13 or type 29 pneumococci. Blood was sampled periodically for the next 24 h, and the following were measured: (i) circulating levels of leukocytes; (ii) activity of the classical and alternate complement pathways; and (iii) ability of the serum to opsonize pneumococci for ingestion and killing by polymorphonuclear leukocytes. Saline-injected control rabbits showed no change in any of the functions. Nonimmune rabbits injected with either pneumococcal serotype showed progressive and profound leukopenia, no change or an increase in classical and alternate complement pathway activity, and a profound reduction in the serum-opsonizing capcity for pneumococci of the same serotype as that used in the injection. The opsonizing capacity remained normal for the other serotype. When a previously immunized animal was injected, the opsonizing capacity for the homologous organism remained intact, but leukopenia nervertheless occurred. PMID:7429626

Reed, W P; Jaffee, P; Albright, E L; Williams, R C

1980-01-01

223

The Genome of Polymorphonuclear Neutrophils Maintains Normal Coding Sequences  

PubMed Central

Genetic studies often use genomic DNA from whole blood cells, of which the majority are the polymorphonuclear myeloid cells. Those cells undergo dramatic change of nuclear morphology following cellular differentiation. It remains elusive if the nuclear morphological change accompanies sequence alternations from the intact genome. If such event exists, it will cause a serious problem in using such type of genomic DNA for genetic study as the sequences will not represent the intact genome in the host individuals. Using exome sequencing, we compared the coding regions between neutrophil, which is the major type of polymorphonuclear cells, and CD4+ T cell, which has an intact genome, from the same individual. The results show that exon sequences between the two cell types are essentially the same. The minor differences represented by the missed exons and base changes between the two cell types were validated to be mainly caused by experimental errors. Our study concludes that genomic DNA from whole blood cells can be safely used for genetic studies. PMID:24250807

Wen, Hongxiu; Luo, Jiangtao; Chen, Peixian; Cowan, Kenneth; Wang, San Ming

2013-01-01

224

Genome-wide transcriptional profiling of peripheral blood leukocytes from cattle infected with Mycobacterium bovis reveals suppression of host immune genes  

PubMed Central

Background Mycobacterium bovis is the causative agent of bovine tuberculosis (BTB), a pathological infection with significant economic impact. Recent studies have highlighted the role of functional genomics to better understand the molecular mechanisms governing the host immune response to M. bovis infection. Furthermore, these studies may enable the identification of novel transcriptional markers of BTB that can augment current diagnostic tests and surveillance programmes. In the present study, we have analysed the transcriptome of peripheral blood leukocytes (PBL) from eight M. bovis-infected and eight control non-infected age-matched and sex-matched Holstein-Friesian cattle using the Affymetrix® GeneChip® Bovine Genome Array with 24,072 gene probe sets representing more than 23,000 gene transcripts. Results Control and infected animals had similar mean white blood cell counts. However, the mean number of lymphocytes was significantly increased in the infected group relative to the control group (P = 0.001), while the mean number of monocytes was significantly decreased in the BTB group (P = 0.002). Hierarchical clustering analysis using gene expression data from all 5,388 detectable mRNA transcripts unambiguously partitioned the animals according to their disease status. In total, 2,960 gene transcripts were differentially expressed (DE) between the infected and control animal groups (adjusted P-value threshold ? 0.05); with the number of gene transcripts showing decreased relative expression (1,563) exceeding those displaying increased relative expression (1,397). Systems analysis using the Ingenuity® Systems Pathway Analysis (IPA) Knowledge Base revealed an over-representation of DE genes involved in the immune response functional category. More specifically, 64.5% of genes in the affects immune response subcategory displayed decreased relative expression levels in the infected animals compared to the control group. Conclusions This study demonstrates that genome-wide transcriptional profiling of PBL can distinguish active M. bovis-infected animals from control non-infected animals. Furthermore, the results obtained support previous investigations demonstrating that mycobacterial infection is associated with host transcriptional suppression. These data support the use of transcriptomic technologies to enable the identification of robust, reliable transcriptional markers of active M. bovis infection. PMID:22182502

2011-01-01

225

Polymorphonuclear leucocyte function in Behçet's disease  

Microsoft Academic Search

Polymorphonuclear leucocyte function was investigated in 19 patients with active Behçet's disease. Spontaneous free leucocyte migration was found to be significantly reduced, yet after stimulation the leucocyte's chemotactic activity was considerably increase (p less than 0-05) when compared to control leucocytes. Control leucocytes migrated more rapidly when incubated in serum taken from patients with Behçet's disease (p less than 0-005).

J D Sobel; S Haim; N Obedeanu; T Meshulam; D Merzbach

1977-01-01

226

Development of leukocyte cell lines from the channel catfish ( Ictalurus punctatus )  

Microsoft Academic Search

Summary Techniques are described for the generation of channel catfish long term leukocyte cell lines. These techniques include the isolation of peripheral blood leukocytes, purification of B cells by anti-immunoglobulin panning, mitogen stimulation, and in vitro maintenance and cloning of leukocyte cultures. Once stimulated in vitro, channel catfish leukocytes proliferate continuously without the need for exogenous growth factors or feeder

Norman W. Miller; V. Gregory Chinchar; L. William Clem

1994-01-01

227

LACTOFERRIN, AN IRON-BINBING PROTEIN NI NEUTROPHILIC LEUKOCYTES  

PubMed Central

Lactoferrin, an iron-binding protein previously shown to occur in many external secretions, is identified as one of the major proteins present in human and guinea pig neutrophilic polymorphonuclear leukocytes. The identification of this protein in leukocyte extracts was based upon a comparison of its electrophoretic, antigenic, and iron-combining properties with the corresponding properties of the same protein isolated from human and guinea pig milk. Immunochemical quantitations showed that lactoferrin occurs in human neutrophilic leukocytes at the concentration of 3 µg per 106 cells. Tissue cultures from guinea pig bone marrow and spleen actively synthesized the protein, as shown both by net production of lactoferrin and incorporation of labeled amino acids into the protein. Immunohistochemical data indicate that lactoferrin first appears in myeloid cells at the stage of the promyelocyte. PMID:4979954

Masson, P. L.; Heremans, J. F.; Schonne, E.

1969-01-01

228

Substitution of aspartate for glycine 1018 in the type III procollagen (COL3A1) gene causes type IV Ehlers-Danlos syndrome: the mutated allele is present in most blood leukocytes of the asymptomatic and mosaic mother.  

PubMed Central

A proband with arterial ruptures and skin changes characteristic of the type IV variant of Ehlers-Danlos syndrome was found to have a single-base mutation in the type III procollagen gene, which converted the codon for glycine at amino acid position 1018 to a codon for aspartate. (Amino acid positions are numbered by the standard convention in which the first glycine of the triple-helical domain of an alpha chain is number 1. The numbers of positions in the alpha 1(III) chains can be converted to positions in the human pro alpha(III) chain by adding 167.) Nucleotide sequencing of overlapping PCR products in which the two alleles were distinguished demonstrated that the mutation of glycine 1018 was the only mutation that changed the primary structure of type III procollagen. The glycine substitution markedly decreased the amount of type III procollagen secreted into the medium by cultured skin fibroblasts from the proband. It is surprising that the same mutation was found in about 94% of the peripheral blood leukocytes from the proband's asymptomatic 72-year-old mother. Other tissues from the mother contained the mutated allele; it was present in 0%-100% of different samples of hair cells and in about 40% of cells from the oral epithelium. Therefore, the mother was a mosaic for the mutation. Since the mutated allele was present in cells derived from all three germ layers, the results indicated that the mutation arose by the late blastocyst stage of development. The results also indicate that assays of blood leukocytes do not always reveal mosaicism or predict phenotypic involvement of tissues, such as blood vessels, that are derived from the same embryonic cells as are leukocytes. Images Figure 5 Figure 2 Figure 3 Figure 4 PMID:1496983

Kontusaari, S; Tromp, G; Kuivaniemi, H; Stolle, C; Pope, F M; Prockop, D J

1992-01-01

229

Surface modification of polymeric materials and its effect on blood compatibility  

SciTech Connect

The surfaces of commercially available polymeric materials have been modified through the chemical infusion process and physical vapor deposition. The surfaces of poly(methylmethacrylate) (PMMA) have been modified through a chemical infusion process by treatment of the sample with a solution containing varying amounts of titanium(IV)isopropoxide and polyvinylpyrrolidone (PVP). The surfaces of silicone rubber samples have been coated with a thin coating of titanium dioxide with an ion beam sputtering technique. The treated samples were characterized by scanning electron microscopy, optical microscopy, and neutron activation analysis. The infused samples were evaluated for blood compatibility using two biological assays: an adherence assay in which the adherence of human polymorphonuclear leukocytes to the samples was determined, and a hemolysis assay using rat blood erythrocytes to determine the hemolytic activity of the samples. Based on the results of these assays, the PMMA samples treated with PVP alone resulted in an improvement in reactivity with the blood cells. 16 refs., 4 figs.

Wrobleski, D.A.; Cash, D.L.; Archuleta, T.; Barthell, B.L.; Kossowsky, R.; London, J.E.; Lehnert, B.E.; Duchane, D.V.

1987-01-01

230

The Effect of Hypertonic Saline on mRNA of Proinflammatory Cytokines in Lipopolysaccharide-Stimulated Polymorphonuclear Cells  

PubMed Central

Background Hypertonic saline is often used to resuscitate patients experiencing shock. In such conditions, polymorphonuclear cells and Toll-like receptors (TLRs) form an essential part of early induced innate immunity. Objective To investigate the immunomodulatory effect of hypertonic saline on polymorphonuclear cells by evaluating the changes in TLR-4 receptors and proinflammatory cytokines. Methods Polymorphonuclear cells were isolated from whole blood using Polymorphprep (Axis-Shield, Oslo, Norway). The isolated polymorphonuclear cells were plated at a density of 1 × 106 cells/mL in 6-well flat-bottomed culture plates and were stimulated with 1 ?g/mL lipopolysaccharide or N-formyl-methionyl-leucyl-phenylalanine. The stimulated polymorphonuclear cells were cultured in hypertonic saline at 10, 20, or 40 mmol/L above isotonicity. After that, the changes in TLR-4 and cytokines were measured by quantitative real-time polymerase chain reaction and flow cytometry. Results The level of TLR-4 mRNA expression decreased after stimulation with N-formyl-methionyl-leucyl-phenylalanine, but hypertonic saline did not affect the TLR-4 mRNA expression. TLR-4 mRNA expression was clearly induced upon stimulation with lipopolysaccharide, and the addition of hypertonic saline restored TLR-4 mRNA expression in polymorphonuclear cells. The interleukin-1? mRNA expression was decreased in the hypertonic environment. On the other hand, the tumor necrosis factor-? value was not influenced by the addition of hypertonic saline. Conclusions Hypertonic saline has an immunomodulatory effect on polymorphonuclear cells through the TLR-4 pathway, and the interleukin–1?-associated pathway is influenced more by hypertonic saline than is the tumor necrosis factor–?-associated pathway. PMID:25067987

Choi, Sung-Hyuk; Yoon, Young-Hoon; Kim, Jung-Youn; Moon, Sung-Woo; Cho, Young-Duck; Yeom, Ji-Won

2014-01-01

231

Presence of high levels of leukocyte-associated interleukin-8 upon cell activation and in patients with sepsis syndrome.  

PubMed

In inflammatory and infectious diseases, the presence of circulating cytokines in plasma strongly suggests, following their exacerbated production, that saturation of specific binding sites has occurred or that an equilibrium between receptor-bound and free cytokines has been reached. In this report, we demonstrate that in addition to circulating interleukin-8 (IL-8), high levels of cell-associated IL-8 were detected in blood samples from patients with sepsis syndrome. The following analysis will reveal that in addition to erythrocytes, which have been dubbed a "sink" for IL-8, peripheral blood mononuclear cells (PBMC) and polymorphonuclear cells (PMN) contributed to the detection of cell-associated IL-8. On a per cell basis, 2,000 to 7,000 times the amount of IL-8 was found associated with PMN than with erythrocytes. In addition, circulating cells may well be the source of the leukocyte-associated form of IL-8. Similarly, in vitro experiments, such as whole-blood stimulation assays or the addition of exogenous IL-8 in blood samples, demonstrated that a large proportion of the IL-8 was associated with leukocytes. This suggests that the trapping of free cytokines onto the cell surface and the internalization of the IL-8 bound to its receptor, occurring both in vitro and in vivo, allows the detection of this cell-associated form. This analysis of cell-associated cytokines was extended to IL-1ra, another component of the inflammatory response, which, in contrast to IL-8, has been demonstrated to exist as an intracellular form. Indeed, cell-associated IL-1ra was also detected in septic patients. The measurement of cell-associated proinflammatory and anti-inflammatory cytokines in patients is clearly a more reliable reflection of their production than is the simple measurement in plasma and may provide useful indication to further understand the inflammatory process. PMID:9038289

Marie, C; Fitting, C; Cheval, C; Losser, M R; Carlet, J; Payen, D; Foster, K; Cavaillon, J M

1997-03-01

232

Feature selection and classification of leukocytes using random forest.  

PubMed

In automatic segmentation of leukocytes from the complex morphological background of tissue section images, a vast number of artifacts/noise are also extracted causing large amount of multivariate data generation. This multivariate data degrades the performance of a classifier to discriminate between leukocytes and artifacts/noise. However, the selection of prominent features plays an important role in reducing the computational complexity and increasing the performance of the classifier as compared to a high-dimensional features space. Therefore, this paper introduces a novel Gini importance-based binary random forest feature selection method. Moreover, the random forest classifier is used to classify the extracted objects into artifacts, mononuclear cells, and polymorphonuclear cells. The experimental results establish that the proposed method effectively eliminates the irrelevant features, maintaining the high classification accuracy as compared to other feature reduction methods. PMID:25284218

Saraswat, Mukesh; Arya, K V

2014-12-01

233

Tumor cell lysis by activated human neutrophils: Analysis of neutrophil-delivered oxidative attack and role of leukocyte function-associated antigen 1  

Microsoft Academic Search

The lysis of tumor cells, and other nucleated mammalian cells, by neutrophilic polymorphonuclear leukocytes (PMNs) triggered by phorbol myristate acetate (PMA) represents a widely used model system to dissect the PMN cytolytic armamentarium, potentially responsible for the cell damage at tissue sites of PMN activation. Although oxidants are generally considered to be instrumental in the target lysis by PMNs, the

Franco Dallegri; Luciano Ottonello; Alberto Ballestrero; Patrizia Dapino; Fabio Ferrando; Franco Patrone; Carlo Sacchetti

1991-01-01

234

Platelet-Activating Factor May Act as a Second Messenger in the Release of Icosanoids and Superoxide Anions from Leukocytes and Endothelial Cells  

Microsoft Academic Search

Platelet-activating factor (PAF) is generated by endothelial cells, polymorphonuclear leukocytes, and macrophages after activation by appropriate receptor agonists, but much of the PAF remains intracellular. We have investigated whether PAF formation is important for the subsequent generation of icosanoids and superoxide anions by these cells. The generation of prostacyclin and leukotriene B_4 were measured by radioimmunoassay, superoxide anion was measured

Alastair G. Stewart; Philip N. Dubbin; Trudi Harris; Gregory J. Dusting

1990-01-01

235

Transfer of human leukocytes into double-knockout Pfp-/-Rag2-/- mice grafted with human skin: increased accumulation of neutrophils in human dermal microvessels.  

PubMed

Severe combined immunodeficient mice reconstituted with human leukocytes have been useful to model parts of the human immune system, including some of its diseases (e.g., AIDS). Because no human polymorphonuclear leukocytes (huPMN) develop in these xenograft models, diseases such as several forms of vasculitis cannot be modeled using this approach. To provide such a model for vasculitis, human skin patches were grafted onto double-knockout Pfp(-/-)Rag2(-/-) mice, which not only lack functional T and B cells but which are also devoid of natural killer cells. After intravenous injection, a high proportion of huPMNs survived within the circulation and accumulated in the human blood vessels. The accumulation increased considerably after the endothelium of the skin patches had been stimulated by tumor necrosis factor-alpha. Alpha mild perivascular neutrophilic infiltration and vascular necrosis was observed in the microvessels of the skin patches. Thus, a xenograft model of vasculitis with predominant huPMNs infiltration has been established for the first time. PMID:15599322

Ullrich, Sebastian; Schumacher, Udo; Ai, Maixing; Tiemann, Bastian; Gay, Steffen; Schechner, Jeffery S; Pober, Jordan S; Gross, Wolfgang L; Csernok, Elena

2004-11-27

236

Endometrial leukocytes and menstruation  

Microsoft Academic Search

This review examines evidence supporting the concept that menstruation occurs as a result of an inflammatory process. In the endometrium, leukocyte numbers rise in the late secretory phase following the fall in serum progesterone concentrations. It is postulated that products released following activation of these leukocytes are critically important for menstruation. Mast cells, eosinophils, neutrophils and macrophages in particular are

Lois A. Salamonsen; Louise J. Lathbury

2000-01-01

237

Microhemodynamics and leukocyte sequestration after pulmonary ischemia and reperfusion in rabbits  

Microsoft Academic Search

Objective: Investigation of leukocyte sequestration in alveolar capillaries and of microhemodynamic changes after pulmonary ischemia\\/reperfusion injury. Methods: The kinetics of leukocyte passage and the hemodynamics in pulmonary microcirculation were investigated in 16 rabbits by intravital microscopy. Mean red blood cell velocity and the number of sticking leukocytes were measured in pulmonary arterioles, venules, and capillaries after 1 hour of tourniquet

Gerhard E. H. Kuhnle; Hermann Reichenspurner; Thomas Lange; Florian Wagner; Joachim Groh; Konrad Messmer; Alwin E. Goetz

1998-01-01

238

Leukocyte depletion results in improved lung function and reduced inflammatory response after cardiac surgery  

Microsoft Academic Search

Leukocyte depletion during cardiopulmonary bypass has been demonstrated in animal experiments to improve pulmonary function. Conflicting results have been reported, however, with clinical depletion by arterial line filter of leukocytes at the beginning of cardiopulmonary bypass. In this study, we examined whether leukocyte depletion from the residual heart-lung machine blood at the end of cardiopulmonary bypass would improve lung function

Y. J. Gu; A. J. deVries; P. W. Boonstra; W. van Oeveren

1996-01-01

239

Oxygen radical production by avian leukocytes.  

PubMed Central

Oxygen radical production by heterophils of red-tailed hawks and chickens, and by neutrophils of calves, was evaluated in a chemiluminescence microassay. Leukocytes were isolated by centrifugation of blood in capillary tubes and then challenged with opsonized zymosan in the presence of luminol. Avian heterophils produced significantly fewer oxygen radicals than did bovine neutrophils. PMID:1884301

Conlon, P; Smith, D; Gowlett, T

1991-01-01

240

Coupled Flow-Structure-Biochemistry Simulations of Dynamic Systems of Blood Cells Using an Adaptive Surface Tracking Method  

PubMed Central

A method for the computation of low Reynolds number dynamic blood cell systems is presented. The specific system of interest here is interaction between cancer cells and white blood cells in an experimental flow system. Fluid dynamics, structural mechanics, six-degree-of freedom motion control and surface biochemistry analysis components are coupled in the context of adaptive octree-based grid generation. Analytical and numerical verification of the quasi-steady assumption for the fluid mechanics is presented. The capabilities of the technique are demonstrated by presenting several three-dimensional cell system simulations, including the collision/interaction between a cancer cell and an endothelium adherent polymorphonuclear leukocyte (PMN) cell in a shear flow. PMID:20160939

Hoskins, M.H.; Kunz, R.F.; Bistline, J.E.; Dong, C.

2009-01-01

241

Blood  

MedlinePLUS

... mysterious, life-sustaining fluid called blood. What Is Blood and What Does It Do? Two types of ... mixture of blood cells and plasma. Continue Red Blood Cells Red blood cells (RBCs, and also called ...

242

Blood  

MedlinePLUS

... solid part of your blood contains red blood cells, white blood cells, and platelets. Red blood cells deliver oxygen from your lungs to your tissues and organs. White blood cells fight infection and are part of your body's ...

243

Comparison of leukocyte count and function in smoking and nonsmoking young men.  

PubMed Central

Leukocyte function and other hematological measurements were tested in 14 smoking and 13 nonsmoking young men free of intercurrent or chronic diseases. Leukocyte chemotaxis was depressed in smoking subjects when compared to the same subjects abstaining from cigarettes or to the nonsmokers. Smoking did not affect the whole blood bactericidal capacity of leukocytes and serum for Staphyloccus aureus or Klebsiella pneumoniae. Total leukocyte counts, hematocritis, and monocyte counts were higher in the smoking subjects when compared to the nonsmokers. PMID:1100522

Noble, R C; Penny, B B

1975-01-01

244

Electrophoretic detection of protein p53 in human leukocytes  

SciTech Connect

The authors have found an acid-soluble protein with mol. wt. of about 53 kD in peripheral blood leukocytes of persons with Down's syndrome. It was present in different quantities in all 20 patients tested, but was virtually not discovered in 12 healthy blood donors. This paper determines the possible identity of this protein with protein p53 from mouse ascites carcinoma by comparing their electrophoretic mobilities, because the accuracy of electrophoretic determination of the molecular weight of proteins is not sufficient to identify them. The paper also describes experiments to detect a protein with electrophoretic mobility identical with that of a protein in the leukocytes of patients with Down's syndrome in leukocytes of patients with leukemia. To discover if protein p53 is involved in cell proliferation, the protein composition of leukocytes from healthy blood donors, cultured in the presence and absence of phytohemagglutinin (PHA), was compared. Increased incorporation of H 3-thymidine by leukocytes of patients with Down's syndrome is explained by the presence of a population of immature leukocytes actively synthesizing DNA in the peripheral blood of these patients, and this can also explain the presence of protein p53 in the leukocytes of these patients.

Paponov, V.D.; Kupsik, E.G.; Shcheglova, E.G.; Yarullin, N.N.

1986-01-01

245

Endogenous Tetrapyrroles Influence Leukocyte Responses to Lipopolysaccharide in Human Blood: Pre-Clinical Evidence Demonstrating the Anti-Inflammatory Potential of Biliverdin  

PubMed Central

Sepsis is associated with abnormal host immune function in response to pathogen exposure, including endotoxin (lipopolysaccharide; LPS). Cytokines play crucial roles in the induction and resolution of inflammation in sepsis. Therefore, the primary aim of this study was to investigate the effects of endogenous tetrapyrroles, including biliverdin (BV) and unconjugated bilirubin (UCB) on LPS-induced cytokines in human blood. Biliverdin and UCB are by products of haem catabolism and have strong cytoprotective, antioxidant and anti-inflammatory effects. In the present study, whole human blood supplemented with BV and without was incubated in the presence or absence of LPS for 4 and 8 hours. Thereafter, whole blood was analysed for gene and protein expression of cytokines, including IL-1?, IL-6, TNF, IFN-?, IL-1Ra and IL-8. Biliverdin (50 ?M) significantly decreased the LPS-mediated gene expression of IL-1?, IL-6, IFN-?, IL-1Ra and IL-8 (P<0.05). Furthermore, BV significantly decreased LPS-induced secretion of IL-1? and IL-8 (P<0.05). Serum samples from human subjects and, wild type and hyperbilirubinaemic Gunn rats were also used to assess the relationship between circulating bilirubin and cytokine expression/production. Significant positive correlations between baseline UCB concentrations in human blood and LPS-mediated gene expression of IL-1? (R=0.929), IFN-? (R=0.809), IL-1Ra (R=0.786) and IL-8 (R=0.857) were observed in blood samples (all P<0.05). These data were supported by increased baseline IL-1? concentrations in hyperbilirubinaemic Gunn rats (P<0.05). Blood samples were also investigated for complement receptor-5 (C5aR) expression. Stimulation of blood with LPS decreased gene expression of C5aR (P<0.05). Treatment of blood with BV alone and in the presence of LPS tended to decrease C5aR expression (P=0.08). These data indicate that supplemented BV inhibits the ex vivo response of human blood to LPS. Surprisingly, however, baseline UCB was associated with heighted inflammatory response to LPS. This is the first study to explore the effects of BV in a preclinical human model of inflammation and suggests that BV could represent an anti-inflammatory target for the prevention of LPS mediated inflammation in vivo. PMID:25177524

Bisht, Kavita; Tampe, Jens; Shing, Cecilia; Bakrania, Bhavisha; Winearls, James; Fraser, John; Wagner, Karl-Heinz; Bulmer, Andrew C.

2014-01-01

246

Simvastatin inhibits Staphylococcus aureus alpha toxin mediated polymorphonuclear leukocyte-induced vasocontraction and endothelial dysfunction  

Microsoft Academic Search

Zusammenfassung Simvastatin, ein HMG-CoA-Reduktase-Inhibitor, wird im klinischen Alltag zur Senkung des Cholesterin-Spiegels eingesetzt. Darüber hinaus berichteten aktuelle Studien über protektive Eigenschaften von Statinen unter inflammatorischen Bedingungen. In dieser Studie wurden die Effekte von Simvastatin auf die Leukozyten-vermittelte Schädigung nach Stimulation mit Staphylococcus aureus alpha-Toxin untersucht. Aortale Gefäßsegmente von Ratten, vorbehandelt mit NaCl oder Simvastatin (100 µg\\/kg) intraperitoneal appliziert, wurden isoliert.

U. Buerke; M. Ruß; H. Schmidt; R. Prondzinsky; U. Sibelius; U. Grandel; F. Grimminger; W. Seeger; K. Werdan; M. Buerke

2005-01-01

247

Fate of surface proteins of rabbit polymorphonuclear leukocytes during phagocytosis. I. Identification of surface proteins  

PubMed Central

To study the fate of external membrane proteins during phagocytosis, rabbit peritoneal neutrophils were labeled by enzymatic iodination. Iodine was incorporated into at least 13 proteins ranging in size from approximately 250,000 to 18,000 daltons as judged from autoradiography of gels after SDS-polyacrylamide gel electrophoresis of labeled cells. The major contractile proteins of neutrophils, actin and myosin, were not labeled when intact cells were iodinated but were labeled when homogenates of these cells were iodinated. Nine of the iodinated proteins were released by mild protease treatment of intact cells. A plasma membrane-rich fraction was isolated by density centrifugation. This fraction was enriched at least 10-fold for lactoperoxidase-labeled acid-insoluble proteins. It was enriched to the same extent for the presence of iodinated wheat germ agglutinin that had been bound to intact cells at 4 degrees C before homogenization. Analysis of SDS- polyacrylamide gel electrophoresis revealed that the proteins of this fraction were predominantly of high molecular weight. However, only 8 of the 13 proteins iodinated on intact cells were found in this fraction. The remaining five were enriched in a dense fraction containing nuclei, intact cells, and membranous vesicles, and may represent a specialized segment of the neutrophil cell surface. PMID:479301

1979-01-01

248

Micron-scale positioning of features influences the rate of polymorphonuclear leukocyte migration.  

PubMed Central

Microfabrication technology was used to create regular arrays of micron-size holes (2 microm x 2 microm x 210 nm) on fused quartz and photosensitive polyimide surfaces. The patterned surfaces, which possessed a basic structural element of a three-dimensional (3-D) network (i.e., spatially separated mechanical edges), were used as a model system for studying the effect of substrate microgeometry on neutrophil migration. The edge-to-edge spacing between features was systematically varied from 6 microm to 14 microm with an increment of 2 microm. In addition, collagen was used to coat the patterned quartz surfaces in an attempt to change the adhesive properties of the surfaces. A radial flow detachment assay revealed that cell adhesion was the strongest on the quartz surface (approximately 50% cell attached), whereas it was relatively weaker on polyimide and collagen-coated quartz (approximately 25% cell attached). Cell adhesion to each substrate was not affected either by the presence of holes or by the spacing between holes. A direct visualization assay showed that neutrophil migration on each patterned surface could be characterized as a persistent random walk; the dependence of the random motility coefficient (mu) as a function of spacing was biphasic with the optimal spacing at approximately 10 microm on each substrate. The presence of evenly distributed holes at the optimal spacing of 10 microm enhanced mu by a factor of 2 on polyimide, a factor of 2.5 on collagen-coated quartz, and a factor of 10 on uncoated quartz. The biphasic dependence on the mechanical edges of neutrophil migration on 2-D patterned substrate was strikingly similar to that previously observed during neutrophil migration within 3-D networks, suggesting that microfabricated materials provide relevant models of 3-D structures with precisely defined physical characteristics. In addition, our results demonstrate that the microgeometry of a substrate, when considered separately from adhesion, can play a significant role in cell migration. PMID:11606271

Tan, J; Shen, H; Saltzman, W M

2001-01-01

249

Comparison of granule proteins from human polymorphonuclear leukocytes which are bactericidal toward Pseudomonas aeruginosa.  

PubMed Central

Killing of Pseudomonas aeruginosa by a 55-kDa bactericidal protein (BP 55), a 30-kDa protein (BP 30), cathepsin G, elastase, and proteinase 3 has been compared. P. aeruginosa was resistant to killing by elastase and proteinase 3. BP 55 at a 50% lethal dose (LD50) of 0.23 micrograms of protein per 5 x 10(6) bacteria per ml killed P. aeruginosa and was far more active than BP 30 and cathepsin G. The LD50s of BP 30 and cathepsin G were 16.9 and 28.3 micrograms of protein per 5 x 10(6) bacteria per ml, respectively. Preincubation of BP 55 or BP 30 with lipopolysaccharide (LPS) from P. aeruginosa inhibited bactericidal activity. The N-terminal amino acid sequence of BP 55 and BP 30 revealed no relationship between the two proteins. However, a monoclonal antibody (AHN-15) reacted with both proteins by Western immunoblot. The bactericidal activity of cathepsin G toward P. aeruginosa appeared to be dependent on the availability of the active site of the enzyme; bactericidal activity was inhibited by phenylmethylsulfonyl fluoride (PMSF) and by the specific cathepsin G inhibitor, Z-Gly-Leu-Phe-CH2Cl. The enzyme and bactericidal activities of cathepsin G were also inhibited by LPS from P. aeruginosa. LPS from P. aeruginosa was shown to be a competitive inhibitor of the enzyme activity of cathepsin G. Elastase enzyme activity was also inhibited noncompetitively by LPS, but the enzyme was not bactericidal. We have concluded that all three bactericidal proteins (BP 55, BP 30, and cathepsin G) may bind to the LPS of the outer membrane of P. aeruginosa. It appears that the enzyme active site must be available for cathepsin G to kill P. aeruginosa and that the active site may be involved in the binding of cathepsin G to P. aeruginosa. Images PMID:1937776

Wasiluk, K R; Skubitz, K M; Gray, B H

1991-01-01

250

Preliminary Characterization of a Polymorphonuclear Leukocyte Stimulant Isolated From Alkali-Treated Collagen  

Microsoft Academic Search

This study reports the preliminary characterization of a stimulant released from alkali-treated colla- gen which activates the respiratory burst of PMNs. The supernatant fraction from alkali-treated collagen (SATC) was precipitated with ammonium sulfate, resuspended, and centrifuged through a sucrose gradient (10-30%, W\\/V). Proteins were detected throughout the gradient but PMN stimula- tory activity was found mainly in fractions 1 and

Roswell R. Pfister; Jeffrey L. Haddox; Kwok-Wai Lam; Kimberly M. Lank

1988-01-01

251

Complement Activation by Myeloperoxidase Products Released from Stimulated Human Polymorphonuclear Leukocytes  

Microsoft Academic Search

Purified human myeloperoxidase (MPO) converted human C5 to an activated form, i. e. the C5 protein adopted a configuration expressing a binding site for C6; the resulting C56 complex then reacted with C7, C8 and C9 forming a hemolytic C5-9 complex. For the activation by myeloperoxidase chloride and hydrogen peroxide were essential. This indicates that the peroxidase acted through the

Walther Vogt

1996-01-01

252

Recommendations for Donor Human Leukocyte Antigen Assessment and Matching for Allogeneic Stem Cell Transplantation: Consensus Opinion of the Blood and Marrow Transplant Clinical Trials Network (BMT CTN).  

PubMed

The Blood and Marrow Transplant Clinical Trials Network (BMT CTN) conducts large, multi-institutional clinical trials with the goal of improving the outcomes of hematopoietic cell transplantation (HCT) for patients with life-threatening disorders. Well-designed HCT trials benefit from standardized criteria for defining diagnoses, treatment plans, and graft source selection. In this perspective, we summarize evidence supporting criteria for the selection of related and unrelated adult volunteer progenitor cell donors or umbilical cord blood units. These standardized criteria for graft source selection have been adopted by the BMT CTN to enhance the interpretation of clinical findings within and among future clinical protocols. PMID:25278457

Howard, C Alan; Fernandez-Vina, Marcelo A; Appelbaum, Frederick R; Confer, Dennis L; Devine, Steven M; Horowitz, Mary M; Mendizabal, Adam; Laport, Ginna G; Pasquini, Marcelo C; Spellman, Stephen R

2015-01-01

253

Leukocyte adhesion to the vascular endothelium (the layer of cells that lines the blood vessel walls) plays a central role in  

E-print Network

walls) plays a central role in normal and pathological inflammation (e.g., host response to infection a cascade of adhesive events commonly referred to as initial tethering, rolling, firm adhesion may detach back into the free stream or begin to roll in the direction of the blood flow. This rolling

Tees, David F.J.

254

Acridine orange leukocyte fluorography in mice.  

PubMed

Simultaneous non-invasive visualization of blood vessels and nerves in patients can be obtained in the eye. The retinal vasculature is a target of many retinopathies. Inflammation, readily manifest by leukocyte adhesion to the endothelial lining, is a key pathophysiological mechanism of many retinopathies, making it a valuable and ubiquitous target for disease research. Leukocyte fluorography has been extensively used in the past twenty years; however, fluorescent markers, visualization techniques, and recording methods have differed between studies. The lack of detailed protocol papers regarding leukocyte fluorography, coupled with lack of uniformity between studies, has led to a paucity of standards for leukocyte transit (velocity, adherence, extravasation) in the retina. Here, we give a detailed description of a convenient method using acridine orange (AO) and a commercially available scanning laser ophthalmoscope (SLO, HRA-OCT Spectralis) to view leukocyte behavior in the mouse retina. Normal mice are compared to mice with acute and chronic inflammation. This method can be readily adopted in many research labs. PMID:24333760

Cahoon, Judd M; Olson, Paul R; Nielson, Spencer; Miya, Tadashi R; Bankhead, Peter; McGeown, J Graham; Curtis, Timothy M; Ambati, Balamurali K

2014-03-01

255

Bovine leukocyte adhesion deficiency: in vitro assessment of neutrophil function and leukocyte integrin expression.  

PubMed Central

Bovine leukocyte adhesion deficiency (BLAD) was identified in a two-month-old Holstein heifer calf using DNA-polymerase chain reaction analysis of the affected calf and other clinical parameters. Neutrophil integrin expression (CD18, CD11a, CD11c), aggregation, and transendothelial migration were studied in vitro. Neutrophils were isolated from the affected calf and from normal, healthy, age-matched control Holstein calves. Neutrophils isolated from the affected BLAD calf had decreased expression of leukocyte integrins on their cell surface, decreased ability to aggregate in response to chemotactic stimuli, and decreased ability to migrate across bovine endothelial cell monolayers in vitro. Transendothelial migration of neutrophils from normal calves was reduced to levels comparable to the BLAD neutrophils by treatment with an anti-CD18 monoclonal antibody (MAb 60.3). Peripheral-blood lymphocytes from the BLAD calf also expressed negligible levels of leukocyte integrins, similar to their neutrophil counterparts. Our experimental findings in vitro correlate well with the clinical observations of decreased leukocyte trafficking and diminished host defense in leukocyte adhesion-deficient animals. The syndrome of BLAD may be a suitable model for one of the human leukocyte adhesion deficiency disorders. Images Fig. 4. PMID:7911733

Olchowy, T W; Bochsler, P N; Neilsen, N R; Welborn, M G; Slauson, D O

1994-01-01

256

Effects of the Tumor-Leukocyte Microenvironment on Melanoma–Neutrophil Adhesion to the Endothelium in a Shear Flow  

PubMed Central

The primary cause of cancer mortality is not attributed to primary tumor formation, but rather to the growth of metastases at distant organ sites. Tumor cell adhesion to blood vessel endothelium (EC) and subsequent transendothelial migration within the circulation are critical components of the metastasis cascade. Previous studies have shown polymorphonuclear neutrophils (PMNs) may facilitate melanoma cell adhesion to the EC and subsequent extravasation under flow conditions. The melanoma cell–PMN interactions are found to be mediated by the binding between intercellular adhesion molecule-1 (ICAM-1) on melanoma cells and ?2 integrin on PMNs and by endogenously secreted interleukin 8 (IL-8) within the tumor-leukocyte microenvironment. In this study, the effects of fluid convection on the IL-8-mediated activation of PMNs and the binding kinetics between PMNs and melanoma cells were investigated. Results indicate that the shear rate dependence of PMN–melanoma cell adhesion and melanoma cell extravasation is due, at least partly, to the convection of tumor-secreted proinflammatory cytokine IL-8. PMID:19865613

Liang, Shile; Hoskins, Meghan; Khanna, Payal; Kunz, Robert F.; Dong, Cheng

2009-01-01

257

Hypomethylation of the IL17RC Promoter in Peripheral Blood Leukocytes is Not A Hallmark of Age-Related Macular Degeneration  

PubMed Central

SUMMARY Age-related macular degeneration (AMD) is a leading cause of visual impairment worldwide. Aberrant DNA methylation within the promoter of IL17RC in peripheral blood mononuclear cells has recently been reported in AMD. To validate this association, we examined DNA methylation of the IL17RC promoter in peripheral blood. First, we used Illumina Human Methylation450 Bead Arrays, a widely-accepted platform for measuring global DNA methylation. Second, methylation status at multiple sites within the IL17RC promoter was determined by bisulfite pyrosequencing in two cohorts. Third, a methylation-sensitive QPCR-based assay was performed on a subset of samples. In contrast to previous findings, we did not find evidence of differential methylation between AMD cases and age-matched controls. We conclude that hypomethylation within the IL17RC gene promoter in peripheral blood is not suitable for use as a clinical biomarker of AMD. This study highlights the need for considerable replication of epigenetic association studies prior to clinical application. PMID:24373284

Oliver, Verity F; Franchina, Maria; Jaffe, Andrew E; Branham, Kari E; Othman, Mohammad; Heckenlively, John R; Swaroop, Anand; Campochiaro, Betsy; Vote, Brendan J; Craig, Jamie E; Saffery, Richard; Mackey, David A; Qian, Jiang; Zack, Donald J; Hewitt, Alex W; Merbs, Shannath L

2014-01-01

258

Effects of DHA- Rich n-3 Fatty Acid Supplementation on Gene Expression in Blood Mononuclear Leukocytes: The OmegAD Study  

PubMed Central

Background Dietary fish oil, rich in n-3 fatty acids (n-3 FAs), e.g. docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), regulate inflammatory reactions by various mechanisms, e.g. gene activation. However, the effects of long-term treatment with DHA and EPA in humans, using genome wide techniques, are poorly described. Hence, our aim was to determine the effects of 6 mo of dietary supplementation with an n-3 FA preparation rich in DHA on global gene expression in peripheral blood mononuclear cells. Methods and Findings In the present study, blood samples were obtained from a subgroup of 16 patients originating from the randomized double-blind, placebo-controlled OmegAD study, where 174 Alzheimer disease (AD) patients received daily either 1.7 g of DHA and 0.6 g EPA or placebo for 6 months. In blood samples obtained from 11 patients receiving n-3 FA and five placebo, expressions of approximately 8000 genes were assessed by gene array. Significant changes were confirmed by real-time PCR. At 6 months, the n-3 FAs group displayed significant rises of DHA and EPA plasma concentrations, as well as up- and down-regulation of nine and ten genes, respectively, was noticed. Many of these genes are involved in inflammation regulation and neurodegeneration, e.g. CD63, MAN2A1, CASP4, LOC399491, NAIP, and SORL1 and in ubiqutination processes, e.g. ANAPC5 and UBE2V1. Down-regulations of ANAPC5 and RHOB correlated to increases of plasma DHA and EPA levels. Conclusions We suggest that 6 months of dietary n-3 FA supplementation affected expression of genes that might influence inflammatory processes and could be of significance for AD. Trial Registration ClinicalTrials.gov NCT00211159 PMID:22545106

Vedin, Inger; Cederholm, Tommy; Freund-Levi, Yvonne; Basun, Hans; Garlind, Anita; Irving, Gerd Faxén; Eriksdotter-Jönhagen, Maria; Wahlund, Lars-Olof; Dahlman, Ingrid; Palmblad, Jan

2012-01-01

259

Inhibition of PMN leukocytes chemotaxis by thalidomide  

Microsoft Academic Search

The effects of thalidomide on chemotaxis of normal human peripheral blood PMN leukocytes have been studied in vitro. The chemotaxis factor was generated by interacting normal human serum with bovine gamma globulin-antibovine-gamma globulin immune complexes. At concentrations of 1, 10, and 100 µg\\/ml, thalidomide failed to inhibit the chemotactic factor. At the same concentrations, erythromycin caused a marked inhibition of

Michel Faure; Jean Thivolet; Martine Gaucherand

1980-01-01

260

Leukocyte extravasation: chemokine transport and presentation by the endothelium  

Microsoft Academic Search

At sites of inflammation and in normal immune surveillance, chemokines direct leukocyte migration across the endothelium. Many cell types that are extravascular can produce chemokines, and for these\\u000d\\u000amediators to directly elicit leukocyte migration from the blood, they would need to reach the luminal surface of the endothelium. This article reviews the evidence that endothelial cells are active in transcytosing

Angela Patterson; Caroline Schmutz; Brian Ashton

2002-01-01

261

Fusobacterium necrophorum Leukotoxin Induces Activation and Apoptosis of Bovine Leukocytes  

Microsoft Academic Search

Fusobacterium necrophorum, a gram-negative, rod-shaped, anaerobic bacterium, is a primary or secondary etiological agent in a variety of necrotic, purulent infections in humans and animals. Its major virulence factor is leukotoxin, a high-molecular-weight secreted protein, primarily toxic to ruminant leukocytes. In this study, bovine peripheral blood leukocytes were exposed to various concentrations of immunoaffinity-purified leuko- toxin and the cytotoxicity was

Sanjeevkumar Narayanan; George C. Stewart; M. M. Chengappa; Lloyd Willard; Wilma Shuman; Melinda Wilkerson; T. G. Nagaraja

2002-01-01

262

Ontogenetic regulation of leukocyte recruitment in mouse yolk sac vessels  

PubMed Central

In adult mammals, leukocyte recruitment follows a well-defined cascade of adhesion events enabling leukocytes to leave the circulatory system and transmigrate into tissue. Currently, it is unclear whether leukocyte recruitment proceeds in a similar fashion during fetal development. Considering the fact that the incidence of neonatal sepsis increases dramatically with decreasing gestational age in humans, we hypothesized that leukocyte recruitment may be acquired only late during fetal ontogeny. To test this, we developed a fetal intravital microscopy model in pregnant mice and, using LysEGFP (neutrophil reporter) mice, investigated leukocyte recruitment during fetal development. We show that fetal blood neutrophils acquire the ability to roll and adhere on inflamed yolk sac vessels during late fetal development, whereas at earlier embryonic stages (before day E15), rolling and adhesion were essentially absent. Accordingly, flow chamber experiments showed that fetal EGFP+ blood cells underwent efficient adhesion only when they were harvested on or after E15. Fluorescence-activated cell sorter analysis on EGFP+ fetal blood cells revealed that surface expression of CXCR2 and less pronounced P-selectin glycoprotein ligand-1 (PSGL-1) begin to increase only late in fetal life. Taken together, our findings demonstrate that inflammation-induced leukocyte recruitment is ontogenetically regulated and enables efficient neutrophil trafficking only during late fetal life. PMID:23525796

Quackenbush, Elizabeth J.; Sushkova, Natalia; Altstätter, Johannes; Nussbaum, Claudia; Schmid, Stephan; Pruenster, Monika; Kurz, Angela; Margraf, Andreas; Steppner, Alina; Schweiger, Natalie; Borsig, Lubor; Boros, Ildiko; Krajewski, Nele; Genzel-Boroviczeny, Orsolya; Jeschke, Udo; Frommhold, David

2013-01-01

263

C-type natriuretic peptide inhibits leukocyte recruitment and platelet-leukocyte interactions via suppression of P-selectin expression  

NASA Astrophysics Data System (ADS)

The multifaceted process of immune cell recruitment to sites of tissue injury is key to the development of an inflammatory response and involved in the pathogenesis of numerous cardiovascular disorders. We recently identified C-type natriuretic peptide (CNP) as an important endothelium-derived mediator that regulates vascular tone and protects against myocardial ischemia/reperfusion injury. Herein, we investigated whether CNP inhibits leukocyte recruitment and platelet aggregation and thereby exerts a potential antiinflammatory influence on the blood vessel wall. We assessed the effects of CNP on leukocyte-endothelial cell interactions in mouse mesenteric postcapillary venules in vivo in animals with high basal leukocyte activation (endothelial nitric oxide synthase knockout mice, eNOS-/-) or under acute inflammatory conditions (induced by interleukin-1 or histamine). CNP suppressed basal leukocyte rolling in eNOS-/- mice in a rapid, reversible, and concentration-dependent manner. These effects of CNP were mimicked by the selective natriuretic peptide receptor-C agonist cANF4-23. CNP also suppressed leukocyte rolling induced by IL-1 or histamine, inhibited platelet-leukocyte interactions, and prevented thrombin-induced platelet aggregation of human blood. Furthermore, analysis of human umbilical vein endothelial cells, leukocytes, and platelets revealed that CNP selectively attenuates expression of P-selectin. Thus, CNP is a modulator of acute inflammation in the blood vessel wall characterized by leukocyte and platelet activation. These antiinflammatory effects appear to be mediated, at least in part, via suppression of P-selectin expression. These observations suggest that endothelial CNP might maintain an anti-atherogenic influence on the blood vessel wall and represent a target for therapeutic intervention in inflammatory cardiovascular disorders. endothelium | natriuretic peptide receptor type C | atherosclerosis | thrombosis

Scotland, Ramona S.; Cohen, Marc; Foster, Paul; Lovell, Matthew; Mathur, Anthony; Ahluwalia, Amrita; Hobbs, Adrian J.

2005-10-01

264

In Vitro Expression of Adhesion Receptors and Diapedesis by Polymorphonuclear Neutrophils during Experimentally Induced Streptococcus uberis Mastitis  

PubMed Central

The expression of adhesion receptors and diapedesis by polymorphonuclear neutrophils (PMN) were studied before and during experimentally induced Streptococcus uberis mastitis. Both quarters of the left half of the udders of five midlactation cows were inoculated with a suspension containing approximately 500 CFU of S. uberis 0140J. Clinical signs of an inflammatory reaction and leukocyte influx were observed 24 h after challenge. The expression of CD11b/CD18 adhesion receptors, determined by flow cytometry, was upregulated 24 h after challenge. A confluent monolayer of bovine secretory mammary epithelial cells on collagen-coated inserts was used to study PMN diapedesis. Bovine C5a was used as the chemoattractant. An 80% decrease in PMN diapedesis was observed 24 h after challenge. The decrease in diapedesis continued for 3 weeks after challenge. PMID:9596712

Smits, Elke; Burvenich, Christian; Guidry, Albert J.; Roets, Eddy

1998-01-01

265

Labeling autologous leukocytes with indium-111 oxine  

SciTech Connect

A method is described for labeling autologous leukocytes with indium-111 oxine, which is used for localizing inflammatory processes. To an aqueous solution of indium-111 chloride was added sodium acetate buffer, pH 5.0, and then a freshly prepared solution of oxine (8-hydroxyquinoline) in ethanol. After 3-5 minutes of incubation at room temperature, the chelated indium-111 oxine was extracted with chloroform, evaporated to dryness, redissolved in ethanol, and diluted with 0.9% saline. Leukocytes were isolated from venous blood by centrifugation at 300-350 g and resuspended in 0.9% saline. The cells were labeled by adding the indium-111 oxine solution to the leukocyte suspension. Clinical results have shown indium-111-labeled leukocytes to be highly specific for abscess localization. Indium-111 is useful for imaging because its gamma emissions are suitable for external detection and its half-life of 67 hours allows studies to be performed over several days without presenting an excessive radiation dose to the patient.

Beightol, R.W.; Baker, W.J.

1980-06-01

266

Thermal injury induces impaired function in polymorphonuclear neutrophil granulocytes and reduced control of burn wound infection  

PubMed Central

Severe thermal injury induces immunosuppression, involving all parts of the immune system, especially when large fractions of the total body surface area are affected. An animal model was established to characterize the burn-induced immunosuppression. In our novel mouse model a 6% third-degree burn injury was induced in mice with a hot-air blower. The third-degree burn was confirmed histologically. The mice were allocated into five groups: control, shave, burn, infection and burn infection group. At 48 h, a decline in the concentration of peripheral blood leucocytes was observed in the group of mice with burn wound. The reduction was ascribed to the decline in concentration of polymorphonuclear neutrophil leucocytes and monocytes. When infecting the skin with Pseudomonas aeruginosa, a dissemination of bacteria was observed only in the burn wound group. Histological characterization of the skin showed a more polymorphonuclear neutrophil granulocytes (PMNs)-dominated inflammation in the group of mice with infected burn wound compared with the with burn wound group. In contrast, a higher degree of inflammation was observed in the burn wound group compared with the group of mice with infected burn wound. Furthermore, the oxidative burst and the phagocytic capacity of the PMNs were reduced in the group of mice with burn wound. Using this novel mouse model of thermal injury a decline of peripheral leucocytes was observed, whereas the increased local inflammatory response at the site of infection showed reduced capacity to contain and eliminate the infection. PMID:19210518

Calum, H; Moser, C; Jensen, P Ø; Christophersen, L; Maling, D S; van Gennip, M; Bjarnsholt, T; Hougen, H P; Givskov, M; Jacobsen, G K; Høiby, N

2009-01-01

267

Changes in apoptosis of human polymorphonuclear granulocytes with aging  

Microsoft Academic Search

Many alterations with aging occur at the cellular and organic levels in the immune system ultimately leading to a decrease in the immune response. Our aim in the present work was to study apoptosis of polymorphonuclear granulocytes (PMN) with aging under various stimulations since apoptosis might play an important role in several pathologies encountered with aging. The PMN of healthy

T Fülöp Jr; C Fouquet; P Allaire; N Perrin; G Lacombe; J Stankova; M Rola-Pleszczynski; D Gagné; J. R Wagner; A Khalil; G Dupuis

1997-01-01

268

Mixed chimeric hematopoietic stem cell transplant reverses the disease phenotype in canine leukocyte adhesion deficiency.  

PubMed

The genetic disease canine leukocyte adhesion deficiency (CLAD) is characterized by recurrent, severe bacterial infections, typically culminating in death by 6 months of age. CLAD is due to a mutation in the leukocyte integrin CD18 subunit, which prevents surface expression of the CD11/CD18 leukocyte integrin complex. We demonstrate that stable mixed donor:host hematopoietic chimerism, achieved by a non-myeloablative bone marrow transplant from a histocompatible littermate, reverses the disease phenotype in CLAD. Donor chimerism following the transplant was demonstrated both by flow cytometric detection of donor-derived CD18-positive leukocytes in the peripheral blood of the recipient, and by the demonstration of donor-derived DNA microsatellite repeats in the peripheral blood leukocytes of the recipient. These results indicate that mixed hematopoietic chimerism reverses the clinical phenotype in CLAD and represents a potential therapeutic approach for the human disease leukocyte adhesion deficiency. PMID:12963272

Creevy, Kate E; Bauer, Thomas R; Tuschong, Laura M; Embree, Lisa J; Silverstone, Andrew M; Bacher, John D; Romines, Chris; Garnier, Julie; Thomas, Marvin L; Colenda, Lyn; Hickstein, Dennis D

2003-10-15

269

Platelet-activating factor may participate in signal transduction processes in rabbit leukocytes  

Microsoft Academic Search

The bacterial chemotactic peptide, formyl-methionyl-leucyl-phenylalanine (fMLP), induces the generation of platelet-activating\\u000a factor (PAF), the mobilization of arachidonic acid and generation of superoxide anion (O2\\u000a ?) in rabbit polymorphonuclear leukocytes (PMNs). The PAF receptor antagonists, WEB 2086 (10–100 ?M) and CV 6209 (1–10 ?M),\\u000a reduced the mobilization of arachidonic acid and the O2\\u000a ? generation in response to fMLP but not

Alastair G. Stewart; Trudi Harris

1991-01-01

270

High-density lipoproteins limit neutrophil-induced damage to the blood–brain barrier in vitro  

PubMed Central

Breakdown of the blood–brain barrier (BBB) is a key step associated with ischemic stroke and its increased permeability causes extravasation of plasma proteins and circulating leukocytes. Polymorphonuclear neutrophil (PMN) proteases may participate in BBB breakdown. We investigated the role of PMNs in ischemic conditions by testing their effects on a model of BBB in vitro, under oxygen-glucose deprivation (OGD) to mimic ischemia, supplemented or not with high-density lipoproteins (HDLs) to assess their potential protective effects. Human cerebral endothelial cells cultured on transwells were incubated for 4?hours under OGD conditions with or without PMNs and supplemented or not with HDLs or alpha-1 antitrypsin (AAT, an elastase inhibitor). The integrity of the BBB was then assessed and the effect of HDLs on PMN-induced proteolysis of extracellular matrix proteins was evaluated. The release of myeloperoxidase and matrix metalloproteinase 9 (MMP-9) by PMNs was quantified. Polymorphonuclear neutrophils significantly increased BBB permeability under OGD conditions via proteolysis of extracellular matrix proteins. This was associated with PMN degranulation. Addition of HDLs or AAT limited the proteolysis and associated increased permeability by inhibiting PMN activation. Our results suggest a deleterious, elastase-mediated role of activated PMNs under OGD conditions leading to BBB disruption that could be inhibited by HDLs. PMID:23299241

Bao Dang, Quoc; Lapergue, Bertrand; Tran-Dinh, Alexy; Diallo, Devy; Moreno, Juan-Antonio; Mazighi, Mikael; Romero, Ignacio A; Weksler, Babette; Michel, Jean-Baptiste; Amarenco, Pierre; Meilhac, Olivier

2013-01-01

271

Activated polymorphonuclear cells promote injury and excitability of dorsal root ganglia neurons.  

PubMed

Therapies aimed at depleting or blocking the migration of polymorphonuclear leukocytes (PMN or neutrophils) are partially successful in the treatment of neuroinflammatory conditions and in attenuating pain following peripheral nerve injury or subcutaneous inflammation. However, the functional effects of PMN on peripheral sensory neurons such as dorsal root ganglia (DRG) neurons are largely unknown. We hypothesized that PMN are detrimental to neuronal viability in culture and increase neuronal activity and excitability. We demonstrate that isolated peripheral PMN are initially in a relatively resting state but undergo internal oxidative burst and activation by an unknown mechanism within 10 min of co-culture with dissociated DRG cells. Co-culture for 24 h decreases neuronal count at a threshold<0.4:1 PMN:DRG cell ratio and increases the number of injured and apoptotic neurons. Within 3 min of PMN addition, fluorometric calcium imaging reveals intracellular calcium transients in small size (<25 microm diam) and large size (>25 microm diam) neurons, as well as in capsaicin-sensitive neurons. Furthermore, small size isolectin B4-labeled neurons undergo hyperexcitability manifested as decreased current threshold and increased firing frequency. Although co-culture of PMN and DRG cells does not perfectly model neuroinflammatory conditions in vivo, these findings suggest that activated PMN can potentially aggravate neuronal injury and cause functional changes to peripheral sensory neurons. Distinguishing the beneficial from the detrimental effects of PMN on neurons may aid in the development of more effective drug therapies for neurological disorders involving neuroinflammation, including painful neuropathies. PMID:18201702

Shaw, S K; Owolabi, S A; Bagley, J; Morin, N; Cheng, E; LeBlanc, B W; Kim, M; Harty, P; Waxman, S G; Saab, C Y

2008-04-01

272

Getting Leukocytes to the Site of Inflammation  

PubMed Central

There is no “response” in either the innate or adaptive immune response unless leukocytes cross blood vessels. They do this through the process of diapedesis, in which the leukocyte moves in ameboid fashion through tightly apposed endothelial borders (paracellular transmigration) and in some cases through the endothelial cell itself (transcellular migration). This review summarizes the steps leading up to diapedesis, then focuses on the molecules and mechanisms responsible for transendothelial migration. Surprisingly, many of the same molecules and mechanisms that regulate paracellular migration also control transcellular migration, including a major role for membrane from the recently described lateral border recycling compartment. A hypothesis that integrates the various known mechanisms of transmigration is proposed. PMID:23345459

Muller, W. A.

2013-01-01

273

Leukocyte margination in alveolar capillaries: interrelationship with functional capillary geometry and microhemodynamics.  

PubMed

The pulmonary capillary microvasculature harbors a large pool of intravascularly marginated leukocytes. In this study, we investigated the interrelationship of leukocyte margination with characteristics of functional capillary geometry and microhemodynamics in alveolar capillary networks. In 22 anesthetized rabbits we assessed functional capillary density, average capillary length, red blood cell velocity and leukocyte kinetics in alveolar capillary networks in vivo by intravital fluorescence microscopy. In alveolar wall areas of 12,800 +/- 1,800 microm(2), we detected 3.6 +/- 0.5 sticking leukocytes and 21.0 +/- 1.9 functional capillary segments with an average capillary length of 35.7 +/- 2.1 microm. We calculated that approximately 15% of functional capillary segments are blocked by marginated leukocytes. Leukocyte margination was predominantly observed in capillary networks characterized by a high functional capillary density, short capillary segments and low red blood cell velocities. The multitude of interconnected capillary channels in these networks may allow alveolar blood flow to bypass marginated leukocytes. Hence, this interrelationship may be relevant for maintenance of adequate alveolar perfusion and low capillary network resistance despite excessive leukocyte margination in the pulmonary microvasculature. Local microhemodynamic factors may play a regulatory role in the spatial distribution of leukocyte margination. PMID:10474041

Kuebler, W M; Kuhnle, G E; Goetz, A E

1999-01-01

274

Leukocyte Profiles in Wild House Finches with and without Mycoplasmal Conjunctivitis, a Recently Emerged Bacterial Disease  

Microsoft Academic Search

Leukocyte profiles (relative numbers of white blood cell types) have been used by a growing number of ecological studies to assess immune function and stress in wild birds. House Finches ( Carpodacus mexicanus) in eastern North America are susceptible to an eye disease caused by the bacterium Mycoplasma gallisepticum, providing the opportunity to examine whether leukocyte profiles are associated with

Andrew K. Davis; Katherine C. Cook; Sonia Altizer

2004-01-01

275

COMPARATIVE CHARACTERISTICS OF THE LEUKOCYTIC AND TEMPERATURE REACTION OF ANIMALS TO THE RADIATION EFFECT  

Microsoft Academic Search

The natare of body temperature changes and peripheral blood composition, ; observed shortly after single total irradiation of rabbits (1500 r), shows that ; the temperature and leukocytic reactions become manifest simultaneously and ; irrespective of each other. During subsequent periods (24, 45, and 72 hours ; after irradiation) the leukocyte count changes with time following the ; irradiation and

Volokhova

1961-01-01

276

Quantitative gene expression of cytokines in peripheral blood leukocytes stimulated in vitro: modulation by the anti-tumor nerosis factor-alpha antibody infliximab and comparison with the mucosal cytokine expression in patients with ulcerative colitis.  

PubMed

Emerging data indicate that alterations in cytokine synthesis play a role in inflammatory bowel disease (IBD) pathogenesis. In this study, we quantified mRNA expression of the main acute-phase cytokines and T-cell cytokines in biopsies from patients with established ulcerative colitis (UC) and compared it with that obtained in biopsies from normal controls. Quantification of cytokine gene expression was also evaluated in in vitro phytohemagglutinin (PHA)-treated peripheral blood leukocytes (PBLs) at the RNA and protein levels. The in vitro influence of the anti-tumor necrosis factor-alpha (TNF-alpha) antibody infliximab (INFL) on PHA-treated PBLs was also evaluated. Analyzing inflamed specimens from UC patients compared with control samples, interleukin (IL)-6 was sharply the most induced cytokine. Interestingly, similar results were found in activated PBLs, where acute-phase cytokines were more abundantly expressed compared with T-cell cytokines. IL-6 was confirmed to be the most induced with a maximum increase of 1110-fold after 4 h of PHA stimulation, followed by TNF-alpha and IL-1beta as well as interferon-gamma (IFN-gamma). Surprisingly, analyzing cytokine-mRNA expression from activated PBLs, the time kinetics and quantity of IFN-gamma was more similar to that of the acute-phase proteins than to that of the T-cell cytokines, which were upregulated after 1 h. The upregulation of cytokine-mRNA was translated into protein as demonstrated by enzyme-linked immunosorbent assay. IFN-gamma was also strongly expressed in the RNA from UC biopsies. TNF-alpha protein was not detectable at all in INFL-treated cultures. INFL did not induce a reduction of TNF-alpha-mRNA nor of IL-1beta-mRNA, but it reduced IFN-gamma- mRNA and, to a lesser extent, IL-6-mRNA; it also reduced the T-cell-derived cytokine IL-2. The in vitro model of PHA-stimulated PBLs may mimic inflammation processes observed in vivo. INFL may reduce inflammation in vivo through inhibition of both monocyte and T-cell activation. PMID:17900510

Moriconi, Federico; Raddatz, Dirk; Ho, Ngoc Anh Huy; Yeruva, Sunil; Dudas, Jozsef; Ramadori, Giuliano

2007-10-01

277

Telomeric DNA in normal and leukemic blood cells.  

PubMed Central

We studied telomeric DNA in leukemic cells as well as in normal T cells, B cells, monocytes, polymorphonuclear leukocytes, and bone marrow hematopoietic progenitor cells. No marked differences were observed in the sizes of the telomeric repeats in the various populations of normal blood cells obtained from donors in their twenties to sixties, and the telomere length ranged between 8.5 and 9.0 kb. The leukemic cells of 12 patients with acute leukemia (seven with myeloid and five with lymphoid leukemia) showed a variable reduction in the length of telomeric DNA, ranging from 2.7 to 6.4 kb. The average telomere length was 4.8 and 4.7 kb in myeloid and lymphoid leukemia, respectively, while the telomere length in peripheral blood mononuclear cells obtained from the same patients during complete remission was 8.5 and 7.9 kb, respectively. When the same Southern blots were hybridized with Alu or alphoid sequences, no marked changes in the sizes of the repetitive DNA sequences were observed, indicating that the DNA abnormality in the leukemic cells was specific to the telomere region. Investigation of telomeric DNA changes may be helpful in determining the biological properties of leukemic cells. Images PMID:7883960

Yamada, O; Oshimi, K; Motoji, T; Mizoguchi, H

1995-01-01

278

Local Oxidative and Nitrosative Stress Increases in the Microcirculation during Leukocytes-Endothelial Cell Interactions  

PubMed Central

Leukocyte-endothelial cell interactions and leukocyte activation are important factors for vascular diseases including nephropathy, retinopathy and angiopathy. In addition, endothelial cell dysfunction is reported in vascular disease condition. Endothelial dysfunction is characterized by increased superoxide (O2•?) production from endothelium and reduction in NO bioavailability. Experimental studies have suggested a possible role for leukocyte-endothelial cell interaction in the vessel NO and peroxynitrite levels and their role in vascular disorders in the arterial side of microcirculation. However, anti-adhesion therapies for preventing leukocyte-endothelial cell interaction related vascular disorders showed limited success. The endothelial dysfunction related changes in vessel NO and peroxynitrite levels, leukocyte-endothelial cell interaction and leukocyte activation are not completely understood in vascular disorders. The objective of this study was to investigate the role of endothelial dysfunction extent, leukocyte-endothelial interaction, leukocyte activation and superoxide dismutase therapy on the transport and interactions of NO, O2•? and peroxynitrite in the microcirculation. We developed a biotransport model of NO, O2•? and peroxynitrite in the arteriolar microcirculation and incorporated leukocytes-endothelial cell interactions. The concentration profiles of NO, O2•? and peroxynitrite within blood vessel and leukocytes are presented at multiple levels of endothelial oxidative stress with leukocyte activation and increased superoxide dismutase accounted for in certain cases. The results showed that the maximum concentrations of NO decreased ?0.6 fold, O2•? increased ?27 fold and peroxynitrite increased ?30 fold in the endothelial and smooth muscle region in severe oxidative stress condition as compared to that of normal physiologic conditions. The results show that the onset of endothelial oxidative stress can cause an increase in O2•? and peroxynitrite concentration in the lumen. The increased O2•? and peroxynitrite can cause leukocytes priming through peroxynitrite and leukocytes activation through secondary stimuli of O2•? in bloodstream without endothelial interaction. This finding supports that leukocyte rolling/adhesion and activation are independent events. PMID:22719984

Kar, Saptarshi; Kavdia, Mahendra

2012-01-01

279

Quantitative analysis of human herpesvirus-6 and human cytomegalovirus in blood and saliva from patients with acute leukemia.  

PubMed

Human herpesvirus-6 (HHV-6) and human cytomegalovirus (HCMV) DNAs were quantified by real-time PCR assays in blood and saliva obtained from 50 patients with acute leukemia at the time of diagnosis (50 of each matrix), aplasia (65 of each matrix), remission (55 of each matrix), and relapse (20 of each matrix) to evaluate which biological matrix was more suitable to identify a viral reactivation, search for a possible link between HHV-6 and HCMV reactivations, and evaluate the relations between viral loads and count of different leukocyte types in blood. The median HHV-6 loads were 136; 219; 226, and 75 copies/million cells in blood at diagnosis, aplasia, remission and relapse, respectively. The HCMV loads were 193 and 317 copies/million cells in blood at diagnosis and remission. In the saliva samples, the HHV-6 loads were 22,165; 15,238; 30,214, and 17,454 copies/million cells at diagnosis, aplasia, remission, and relapse, respectively. The HCMV loads were 8,991; 1,461; 2,980, and 4,283 copies/million cells at diagnosis, aplasia, remission, and relapse, respectively. The HHV-6 load in the blood was correlated to the counts of polymorphonuclear leukocytes (R(2) ?=?0.5; P?blood in the detection of HHV-6 or HCMV reactivations. The HHV-6 and HCMV reactivations were linked only in saliva. J. Med. Virol. 87:451-460, 2015. © 2014 Wiley Periodicals, Inc. PMID:25163462

Nefzi, Faten; Ben Salem, Nabil Abid; Khelif, Abderrahim; Feki, Salma; Aouni, Mahjoub; Gautheret-Dejean, Agnès

2015-03-01

280

Analysis of SLC11A1 gene expression in healthy water buffalo (Bubalus bubalis) blood cells using qPCR.  

PubMed

SLC11A1 (solute carrier family 11 member 1 protein) gene influences the initial phase of bacterial cellular infections through macrophage activation. Recent literature on buffalo has attempted to associate the genotype of the polymorphic microsatellite located in the 3'untranslated region (3'UTR) of the gene, with either susceptibility to brucellosis or with improved macrophage function. Carriers of the (GT)16 allele have been reported to be resistant to brucellosis. In this study we analyzed the steady-state level of SLC11A1 expression in a serologically negative herd of 26 animals differing by the number of (GT)n microsatellite repeats by using a reverse transcriptase quantitative real-time polymerase chain reaction approach. We evaluated five different reference genes, which had not been reported previously, for use in gene expression experiments in buffalo blood. However, we did not find any significant difference between buffalo carriers of the different microsatellite alleles, with respect to SLC11A1 expression in whole blood or in blood fractions [peripheral blood mononuclear cells (PBMC) and polymorphonuclear leukocytes/granulocytes (PMN/G)]. Conversely, there was a difference between the blood fractions in their SLC11A1 expression levels, with the PMN/G fraction having a higher expression level than the PBMC fraction (P < 0.015). PMID:24391044

Crisà, A; De Matteis, G; Scatà, M C; Moioli, B

2013-01-01

281

Red blood cells serve as intravascular carriers of myeloperoxidase.  

PubMed

Myeloperoxidase (MPO) is a heme enzyme abundantly expressed in polymorphonuclear neutrophils. MPO is enzymatically capable of catalyzing the generation of reactive oxygen species (ROS) and the consumption of nitric oxide (NO). Thus MPO has both potent microbicidal and, upon binding to the vessel wall, pro-inflammatory properties. Interestingly, MPO - a highly cationic protein - has been shown to bind to both endothelial cells and leukocyte membranes. Given the anionic surface charge of red blood cells, we investigated binding of MPO to erythrocytes. Red blood cells (RBCs) derived from patients with elevated MPO plasma levels showed significantly higher amounts of MPO by flow cytometry and ELISA than healthy controls. Heparin-induced MPO-release from patient-derived RBCs was significantly increased compared to controls. Ex vivo experiments revealed dose and time dependency for MPO-RBC binding, and immunofluorescence staining as well as confocal microscopy localized MPO-RBC interaction to the erythrocyte plasma membrane. NO-consumption by RBC-membrane fragments (erythrocyte "ghosts") increased with incrementally greater concentrations of MPO during incubation, indicating preserved catalytic MPO activity. In vivo infusion of MPO-loaded RBCs into C57BL/6J mice increased local MPO tissue concentrations in liver, spleen, lung, and heart tissue as well as within the cardiac vasculature. Further, NO-dependent relaxation of aortic rings was altered by RBC bound-MPO and systemic vascular resistance significantly increased after infusion of MPO-loaded RBCs into mice. In summary, we find that MPO binds to RBC membranes in vitro and in vivo, is transported by RBCs to remote sites in mice, and affects endothelial function as well as systemic vascular resistance. RBCs may avidly bind circulating MPO, and act as carriers of this leukocyte-derived enzyme. PMID:24976018

Adam, Matti; Gajdova, Silvie; Kolarova, Hana; Kubala, Lukas; Lau, Denise; Geisler, Anne; Ravekes, Thorben; Rudolph, Volker; Tsao, Philip S; Blankenberg, Stefan; Baldus, Stephan; Klinke, Anna

2014-09-01

282

Kinetics of reversible-sequestration of leukocytes by the isolated perfused rat lung  

SciTech Connect

The kinetics and morphology of sequestration and margination of rat leukocytes were studied using an isolated perfused and ventilated rat lung preparation. Whole rat blood, bone marrow suspension, or leukocyte suspensions, were used to perfuse the isolated rat lung. The lung was also perfused with latex particle suspensions and the passage of particles through the lung capillaries was studied. When a leukocyte suspension was perfused through the lung in the single-pass mode, the rate of sequestration decreased as more cells were perfused. In contrast, latex particles of a size comparable to that of leukocytes were totally stopped by the lung. When the leukocyte suspension was recirculated through the lung, cells were rapidly removed from circulation until a steady state was reached, after which no net removal of cells by the lung occurred. These results indicate that leukocytes are reversibly sequestered from circulation. The sequestered cells marginated and attached to the luminal surface of the endothelium of post-capillary venules and veins. A mathematical model was developed based on the assumption that the attachment and detachment of leukocytes to blood vessel walls follows first-order kinetics. The model correctly predicts the following characteristics of the system: (a) the kinetics of the sequestration of leukocytes by the lung; (b) the existence of a steady state when a suspension of leukocytes is recirculated through the lung; and (c) the independence of the fraction of cells remaining in circulation from the starting concentration for all values of starting concentration. (ERB)

Goliaei, B.

1980-08-01

283

Transmigration of polymorphnuclear neutrophils and monocytes through the human blood-cerebrospinal fluid barrier after bacterial infection in vitro  

PubMed Central

Background Bacterial invasion through the blood-cerebrospinal fluid barrier (BCSFB) during bacterial meningitis causes secretion of proinflammatory cytokines/chemokines followed by the recruitment of leukocytes into the CNS. In this study, we analyzed the cellular and molecular mechanisms of polymorphonuclear neutrophil (PMN) and monocyte transepithelial transmigration (TM) across the BCSFB after bacterial infection. Methods Using an inverted transwell filter system of human choroid plexus papilloma cells (HIBCPP), we studied leukocyte TM rates, the migration route by immunofluorescence, transmission electron microscopy and focused ion beam/scanning electron microscopy, the secretion of cytokines/chemokines by cytokine bead array and posttranslational modification of the signal regulatory protein (SIRP) ? via western blot. Results PMNs showed a significantly increased TM across HIBCPP after infection with wild-type Neisseria meningitidis (MC58). In contrast, a significantly decreased monocyte transmigration rate after bacterial infection of HIBCPP could be observed. Interestingly, in co-culture experiments with PMNs and monocytes, TM of monocytes was significantly enhanced. Analysis of paracellular permeability and transepithelial electrical resistance confirmed an intact barrier function during leukocyte TM. With the help of the different imaging techniques we could provide evidence for para- as well as for transcellular migrating leukocytes. Further analysis of secreted cytokines/chemokines showed a distinct pattern after stimulation and transmigration of PMNs and monocytes. Moreover, the transmembrane glycoprotein SIRP? was deglycosylated in monocytes, but not in PMNs, after bacterial infection. Conclusions Our findings demonstrate that PMNs and monoctyes differentially migrate in a human BCSFB model after bacterial infection. Cytokines and chemokines as well as transmembrane proteins such as SIRP? may be involved in this process. PMID:23448224

2013-01-01

284

Leukocyte response to eastern equine encephalomyelitis virus in a wild passerine bird.  

PubMed

Leukocyte counts are frequently used to assess the immunologic status of animals; however, few studies have directly looked at the predictive value of leukocyte counts and an animal's ability to respond to an infection with a pathogen. Understanding how an animal's leukocyte profile is altered by an active infection can assist with interpretation of leukocyte profiles in animals for which infection status is not known. In this study we examine the leukocyte counts of gray catbirds (Dumetella carolinensis) infected with eastern equine encephalomyelitis virus (EEEV). Blood smears were collected from infected catbirds on -4, 2, 5, and 14 days postinoculation (dpi) with EEEV, and from a corresponding uninfected control group, to monitor leukocyte counts. Although we found that preinfection leukocyte counts were not a reliable predictive of a catbird's viremia, we did find that infected catbirds exhibited significant hematologic changes in response to EEEV infection. We observed a significant drop in all subpopulations of leukocytes (i.e., lymphocytes, monocytes, and granulocytes) following infection. Lymphocytes and granulocytes still had not recovered to preinfection levels at 14 dpi. Uninfected catbirds also exhibited statistically significant changes in leukocyte counts, but this was due to a slight increase at 14 dpi and was not considered biologically relevant. Studies such as this can provide important information for field ecoimmunologists that use leukocyte counts to assess immunocompetence in free-living animals. PMID:24597116

Owen, J C; Cornelius, E A; Arsnoe, D A; Garvin, M C

2013-12-01

285

Postnatal episodic ozone results in persistent attenuation of pulmonary and peripheral blood responses to LPS challenge  

PubMed Central

Early life is a dynamic period of growth for the lung and immune system. We hypothesized that ambient ozone exposure during postnatal development can affect the innate immune response to other environmental challenges in a persistent fashion. To test this hypothesis, we exposed infant rhesus macaque monkeys to a regimen of 11 ozone cycles between 30 days and 6 mo of age; each cycle consisted of ozone for 5 days (0.5 parts per million at 8 h/day) followed by 9 days of filtered air. Animals were subsequently housed in filtered air conditions and challenged with a single dose of inhaled LPS at 1 yr of age. After completion of the ozone exposure regimen at 6 mo of age, total peripheral blood leukocyte and polymorphonuclear leukocyte (PMN) numbers were reduced, whereas eosinophil counts increased. In lavage, total cell numbers at 6 mo were not affected by ozone, however, there was a significant reduction in lymphocytes and increased eosinophils. Following an additional 6 mo of filtered air housing, only monocytes were increased in blood and lavage in previously exposed animals. In response to LPS challenge, animals with a prior history of ozone showed an attenuated peripheral blood and lavage PMN response compared with controls. In vitro stimulation of peripheral blood mononuclear cells with LPS resulted in reduced secretion of IL-6 and IL-8 protein in association with prior ozone exposure. Collectively, our findings suggest that ozone exposure during infancy can result in a persistent effect on both pulmonary and systemic innate immune responses later in life. PMID:21131396

Maniar-Hew, Kinjal; Postlethwait, Edward M.; Fanucchi, Michelle V.; Ballinger, Carol A.; Evans, Michael J.; Harkema, Jack R.; Carey, Stephan A.; McDonald, Ruth J.; Bartolucci, Alfred A.

2011-01-01

286

Leukocyte behavior in atherosclerosis, myocardial infarction, and heart failure  

PubMed Central

Cardiovascular diseases claim more lives worldwide than any other. Etiologically, the dominant trajectory involves atherosclerosis, a chronic inflammatory process of lipid-rich lesion growth in the vascular wall that can cause life-threatening myocardial infarction (MI). Those who survive MI can develop congestive heart failure, a chronic condition of inadequate pump activity that is frequently fatal. Leukocytes – white blood cells – are important participants at the various stages of cardiovascular disease progression and complication. This review will discuss leukocyte function in atherosclerosis, myocardial infarction, and heart failure. PMID:23307733

Swirski, Filip K.; Nahrendorf, Matthias

2013-01-01

287

Impact of ambient air pollution on the differential white blood cell count in patients with chronic pulmonary disease.  

PubMed

Epidemiologic studies report associations between particulate air pollution and increased mortality from pulmonary diseases. This study was performed to examine whether the exposure to ambient gaseous and particulate air pollution leads to an alteration of the differential white blood cell count in patients with chronic pulmonary diseases like chronic bronchitis, chronic obstructive pulmonary disease, and asthma. A prospective panel study was conducted in Erfurt, Eastern Germany, with 12 repeated differential white blood cell counts in 38 males with chronic pulmonary diseases. Hourly particulate and gaseous air pollutants and meteorological data were acquired. Mixed models with a random intercept adjusting for trend, meteorology, weekday, and other risk variables were used. In this explorative analysis, we found an immediate decrease of polymorphonuclear leukocytes in response to an increase of most gaseous and particulate pollutants. Lymphocytes increased within 24 h in association with all gaseous pollutants but showed only minor effects in regard to particulate air pollution. Monocytes showed an increase associated with ultrafine particles, and nitrogen monoxide. The effect had two peaks in time, one 0-23 h before blood withdrawal and a second one with a time lag of 48-71 h. The increase of particulate and gaseous air pollution was associated with multiple changes in the differential white blood cell count in patients with chronic pulmonary diseases. PMID:20064088

Brüske, Irene; Hampel, Regina; Socher, Martin M; Rückerl, Regina; Schneider, Alexandra; Heinrich, Joachim; Oberdörster, Günter; Wichmann, H-Erich; Peters, Annette

2010-02-01

288

Phospholipase A activity associated with membranes of human polymorphonuclear leucocytes.  

PubMed

Homogenates of human polymorphonuclear leucocytes (granulocytes) contain a Ca2+-dependent phospholipase A with optimal activity pH7.0. This enzyme is membrane-bound and is enriched in crude cytoplasmic-granule fraction. Ratezonal centrifugation of the cytoplasmic-granule fraction demonstrates that the phospholipase A is associated not only with specific- and azurophilic-granule populations but also with an 'empty' vesicular fraction containing 85% of the total alkaline phosphatase activity of whole homogenate. Thus this phospholipase is associated with granule as well as with other cellular membranes of human granulocytes. PMID:23768

Franson, R; Weiss, J; Martin, L; Spitznagel, J K; Elsbach, P

1977-12-01

289

Microfluidic Leukocyte Isolation for Gene Expression Analysis in Critically Ill Hospitalized Patients  

PubMed Central

BACKGROUND Microarray technology is becoming a powerful tool for diagnostic, therapeutic, and prognostic applications. There is at present no consensus regarding the optimal technique to isolate nucleic acids from blood leukocyte populations for subsequent expression analyses. Current collection and processing techniques pose significant challenges in the clinical setting. Here, we report the clinical validation of a novel microfluidic leukocyte nucleic acid isolation technique for gene expression analysis from critically ill, hospitalized patients that can be readily used on small volumes of blood. METHODS We processed whole blood from hospitalized patients after burn injury and severe blunt trauma according to the microfluidic and standard macroscale leukocyte isolation protocol. Side-by-side comparison of RNA quantity, quality, and genome-wide expression patterns was used to clinically validate the microfluidic technique. RESULTS When the microfluidic protocol was used for processing, sufficient amounts of total RNA were obtained for genome-wide expression analysis from 0.5 mL whole blood. We found that the leukocyte expression patterns from samples processed using the 2 protocols were concordant, and there was less variability introduced as a result of harvesting method than there existed between individuals. CONCLUSIONS The novel microfluidic approach achieves leukocyte isolation in <25 min, and the quality of nucleic acids and genome expression analysis is equivalent to or surpasses that obtained from macroscale approaches. Microfluidics can significantly improve the isolation of blood leukocytes for genomic analyses in the clinical setting. PMID:18375483

Russom, Aman; Sethu, Palaniappan; Irimia, Daniel; Mindrinos, Michael N.; Calvano, Steve E.; Garcia, Iris; Finnerty, Celeste; Tannahill, Cynthia; Abouhamze, Amer; Wilhelmy, Julie; López, M. Cecilia; Baker, Henry V.; Herndon, David N.; Lowry, Stephen F.; Maier, Ronald V.; Davis, Ronald W.; Moldawer, Lyle L.; Tompkins, Ronald G.; Toner, Mehmet

2014-01-01

290

Extravasation of leukocytes in comparison to tumor cells  

PubMed Central

The multi-step process of the emigration of cells from the blood stream through the vascular endothelium into the tissue has been termed extravasation. The extravasation of leukocytes is fairly well characterized down to the molecular level, and has been reviewed in several aspects. Comparatively little is known about the extravasation of tumor cells, which is part of the hematogenic metastasis formation. Although the steps of the process are basically the same in leukocytes and tumor cells, i.e. rolling, adhesion, transmigration (diapedesis), the molecules that are involved are different. A further important difference is that leukocyte interaction with the endothelium changes the endothelial integrity only temporarily, whereas tumor cell interaction leads to an irreversible damage of the endothelial architecture. Moreover, tumor cells utilize leukocytes for their extravasation as linkers to the endothelium. Thus, metastasis formation is indirectly susceptible to localization signals that are literally specific for the immune system. We herein compare the extravasation of leukocytes and tumor cells with regard to the involved receptors and the localization signals that direct the cells to certain organs and sites of the body. PMID:19055814

Strell, Carina; Entschladen, Frank

2008-01-01

291

Initial blood storage experiment  

NASA Technical Reports Server (NTRS)

The possibility of conducting experiments with the formed elements of the blood under conditions of microgravity opens up important opportunities to improve the understanding of basic formed element physiology, as well as, contribution to improved preservation of the formed elements for use in transfusion. The physiological, biochemical, and physical changes of the membrane of the erythrocyte, platelet, and leukocyte was studied during storage under two specific conditions: standard blood bank conditions and microgravity, utilizing three FDA approved plastic bags. Storage lesions; red cell storage on Earth; platelet storage on Earth; and leukocyte storage Earth were examined. The interaction of biomaterials and blood cells was studied during storage.

Surgenor, Douglas MACN.

1988-01-01

292

Altered Mitochondrial Function and Oxidative Stress in Leukocytes of Anorexia Nervosa Patients  

PubMed Central

Context Anorexia nervosa is a common illness among adolescents and is characterised by oxidative stress. Objective The effects of anorexia on mitochondrial function and redox state in leukocytes from anorexic subjects were evaluated. Design and setting A multi-centre, cross-sectional case-control study was performed. Patients Our study population consisted of 20 anorexic patients and 20 age-matched controls, all of which were Caucasian women. Main outcome measures Anthropometric and metabolic parameters were evaluated in the study population. To assess whether anorexia nervosa affects mitochondrial function and redox state in leukocytes of anorexic patients, we measured mitochondrial oxygen consumption, membrane potential, reactive oxygen species production, glutathione levels, mitochondrial mass, and complex I and III activity in polymorphonuclear cells. Results Mitochondrial function was impaired in the leukocytes of the anorexic patients. This was evident in a decrease in mitochondrial O2 consumption (P<0.05), mitochondrial membrane potential (P<0.01) and GSH levels (P<0.05), and an increase in ROS production (P<0.05) with respect to control subjects. Furthermore, a reduction of mitochondrial mass was detected in leukocytes of the anorexic patients (P<0.05), while the activity of mitochondrial complex I (P<0.001), but not that of complex III, was found to be inhibited in the same population. Conclusions Oxidative stress is produced in the leukocytes of anorexic patients and is closely related to mitochondrial dysfunction. Our results lead us to propose that the oxidative stress that occurs in anorexia takes place at mitochondrial complex I. Future research concerning mitochondrial dysfunction and oxidative stress should aim to determine the physiological mechanism involved in this effect and the physiological impact of anorexia. PMID:25254642

Victor, Victor M.; Rovira-Llopis, Susana; Saiz-Alarcon, Vanessa; Sangüesa, Maria C.; Rojo-Bofill, Luis; Bañuls, Celia; Falcón, Rosa; Castelló, Raquel; Rojo, Luis; Rocha, Milagros; Hernández-Mijares, Antonio

2014-01-01

293

An evaluation of the role of leukocytes in the pathogenesis of experimentally induced corneal vascularization.  

PubMed Central

Studies of corneal explants in the hamster cheek pouch chamber have demonstrated that blood vessels invade the cornea only if the tissue is first infiltrated by leukocytes. In view of this observation, a comparative study of the events that precede and accompany corneal vascularization was undertaken in various experimental models. A variety of established methods were used to induce corneal vascularization, including exposure of the cornea to noxious agents, intracorneal injection of antigens into sensitized animals, as well as maintaining animals on diets deficient in vitamin A or riboflavin. In all models studied, the corneal vascularization was a manifestation of the reparative phase of the inflammatory response. A conspicuous leukocytic infiltrate of the cornea preceded and accompanied the corneal vascularization in all of the models. Although the lesions varied in several respects in the different models, all models displayed three phases with regard to vascularization: an early prevascular phase of leukocytic infiltration, a second phase where blood vessels persisted in the cornea in the absence of leukocytes. The latent period that preceded vascularization was directly related to the time of the initial leukocytic infiltration. The models in which a delay occurred in the leukocytic invasion displayed a subsequent delay in the vascular ingrowth. Conversely, in experiments where there was a rapid and extensive leukocytic invasion, there was also an early and enhanced corneal vasoproliferative response. In the various modesl investigated, the sites of the leukocytic infiltration and subsequent vascular ingrowth into the cornea paralleled each other. The data further support the hypotheses that leukocytes are a prerequisite to corneal vascularization and that leukocytes produce one or more factors which stimulate directional vascular growth. Images Fig 10 Fig 11 Fig 12 Fig 1 Fig 2 Fig 3 Fig 4 Fig 5 Fig 6 Fig 7 Fig 8 Fig 9 PMID:1137003

Fromer, C. H.; Klintworth, G. K.

1975-01-01

294

Borrelia burgdorferi Organisms Lacking Plasmids 25 and 28-1 Are Internalized by Human Blood Phagocytes at a Rate Identical to That of the Wild-Type Strain  

Microsoft Academic Search

Lyme borreliosis caused by Borrelia burgdorferi is a persistent infection capable of withstanding the host's vigorous immune response. Several reports have shown that the spirochete's linear plasmids 25 and 28-1 are essential for its infectivity. In this context, it was proposed that Borrelia burgdorferi organisms control their uptake by macrophages and polymorphonuclear leukocytes (PMNs) through plasmid-encoded proteins and that this

Samiya Al-Robaiy; Jens Knauer; Reinhard K. Straubinger

2005-01-01

295

Kinetics of fusion of the cytoplasmic granules with phagocytic vacuoles in human polymorphonuclear leukocytes. Biochemical and morphological studies  

PubMed Central

This study on human neutrophils was conducted to measure the kinetics of degranulation of the different cytoplasmic granules into phagocytic vacuoles, and to relate the timing of these events to the burst of respiration that accompanies phagocytosis by these cells. Purified neutrophils were incubated with latex particles opsonized with human immunoglobulin (Ig)G, and phagocytosis was stopped at timed intervals. The cells were examined by electron microscopy to document the sequence of degranulation of the cytoplasmic granules. The azurophil granules and lyosomes were identified by histochemical staining for peroxidase and acid phosphatase, respectively. Phagocytic vacuoles were separated from cell homogenates by floatation on sucrose gradients and assayed for contained lactoferrin, myeloperoxidase, and acid hydrolases. The conclusions drawn from the biochemical and morphological studies were in agreement and indicated: particle uptake and vacuole closure can be completed within 20 s; both the specific and azurophil granules fuse with the phagocytic vacuole much earlier than is generally appreciated, with half-saturation times of 39 s (99% confidence limits, 15-72); oxygen consumption has kinetics similar to those of the fusion of these granules with the phagosome; degranulation of the acid hydrolases beta- glucuronidase, N-acetyl-beta-glucosaminidase (biochemical assays), and acid phosphatase (biochemical assay and electron microscopic cytochemistry) have kinetics of degranulation that are similar to each other but totally different from and much slower than that of myeloperoxidase with half-saturation times of between 354 and 682 s (99% confidence limits, 246-883). This suggests that the acid hydrolases are not co-located with myeloperoxidase in the azurophil granule but are contained in distinct lysosomes, or "tertiary granules". PMID:7364874

1980-01-01

296

A role for lactate dehydrogenases in the survival of Neisseria gonorrhoeae in human polymorphonuclear leukocytes and cervical epithelial cells.  

PubMed

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

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

2014-10-15

297

A second pathway of leukotriene biosynthesis in porcine leukocytes.  

PubMed Central

Incubation of suspensions containing polymorphonuclear and eosinophilic leukocytes with arachidonic acid led to the formation of two pairs of diastereomeric 8,(15S)-dihydroxy-5,9,11,13-icosatetraenoic acids and two erythro-14,15-dihydroxy-5,8,10,12-icosatetraenoic acids. The structures were elucidated by ultraviolet spectroscopy and gas chromatography--mass spectrometric analysis of several derivatives of each compound, catalytic hydrogenation, oxidative ozonolysis with steric analysis of alcohols, and comparison to reference compounds prepared by chemical synthesis. Experiments with 18O2 and H218O indicated that in all six compounds the hydroxyl group at C-15 was derived from molecular oxygen. Two of the diastereomeric 8,15-dihydroxy acids incorporated H218O at C-8, while the other two 8,15-dihydroxy products (also diastereomers) and the 14,15-dihydroxy compounds (geometric isomers) incorporated 18O2 at C-8 and C-14, respectively, in addition to C-15. Two of the 8,15-dihydroxy acids are formed by reaction of water with an unstable allylic epoxide intermediate, (14S,15S)-oxido-5,8,10,12-icosatetraenoic acid; the two 14,15-dihydroxy acids are proposed to be formed by reaction of activated molecular oxygen with the same epoxide, which in turn originates via 15S oxygenation of arachidonic acid. PMID:6272308

Maas, R L; Brash, A R; Oates, J A

1981-01-01

298

Rapid Accumulation of Polymorphonuclear Neutrophils in the Corpus luteum during Prostaglandin F2?-Induced Luteolysis in the Cow  

PubMed Central

Prostaglandin F2? (PGF2?) induces luteolysis within a few days in cows, and immune cells increase in number in the regressing corpus luteum (CL), implying that luteolysis is an inflammatory-like immune response. We investigated the rapid change in polymorphonuclear neutrophil (PMN) numbers in response to PGF2? administration as the first cells recruited to inflammatory sites, together with mRNA of interleukin-8 (IL-8: neutrophil chemoattractant) and P-selectin (leukocyte adhesion molecule) in the bovine CL. CLs were collected by ovariectomy at various times after PGF2? injection. The number of PMNs was increased at 5 min after PGF2? administration, whereas IL-8 and P-selectin mRNA increased at 30 min and 2 h, respectively. PGF2? directly stimulated P-selectin protein expression at 5–30 min in luteal endothelial cells (LECs). Moreover, PGF2? enhanced PMN adhesion to LECs, and this enhancement by PGF2? was inhibited by anti-P-selectin antibody, suggesting that P-selectin expression by PGF2? is crucial in PMN migration. In conclusion, PGF2? rapidly induces the accumulation of PMNs into the bovine CL at 5 min and enhances PMN adhesion via P-selectin expression in LECs. It is suggested that luteolytic cascade by PGF2? may involve an acute inflammatory-like response due to rapidly infiltrated PMNs. PMID:22235260

Shirasuna, Koumei; Jiemtaweeboon, Sineenard; Raddatz, Sybille; Nitta, Akane; Schuberth, Hans-Joachim; Bollwein, Heinrich; Shimizu, Takashi; Miyamoto, Akio

2012-01-01

299

A multiscale SPH particle model of the near-wall dynamics of leukocytes in flow.  

PubMed

A novel multiscale Lagrangian particle solver based on SPH is developed with the intended application of leukocyte transport in large arteries. In such arteries, the transport of leukocytes and red blood cells can be divided into two distinct regions: the bulk flow and the near-wall region. In the bulk flow, the transport can be modeled on a continuum basis as the transport of passive scalar concentrations. Whereas in the near-wall region, specific particle tracking of the leukocytes is required and lubrication forces need to be separately taken into account. Because of large separation of spatio-temporal scales involved in the problem, simulations of red blood cells and leukocytes are handled separately. In order to take the exchange of leukocytes between the bulk fluid and the near-wall region into account, solutions are communicated through coupling of conserved quantities at the interface between these regions. Because the particle tracking is limited to those leukocytes lying in the near-wall region only, our approach brings considerable speedup to the simulation of leukocyte circulation in a test geometry of a backward-facing step, which encompasses many flow features observed in vivo. PMID:24009138

Gholami, Babak; Comerford, Andrew; Ellero, Marco

2014-01-01

300

Chemotaxis for polymorphonuclear leucocytes induced by soluble antigen- antibody complexes.  

PubMed Central

Guinea-pig soluble immune complexes formed either by simply mixing antibody and antigen in excess or by redissolving a washed immune precipitate with antigen, after incubation with fresh serum, could induce a migration of polymorphonuclear leucocytes in vitro. This chemotactic effect of soluble complexes, although less than that of insoluble complexes, persisted despite experimental changes in the specificity, the dose and the class of antibodies. Soluble complexes of various molecular compositions induced chemotaxis but the most efficient complex was of Ab 1 Ag 1 formula. Unlike larger complexes, the Ab 1 Ag 1 complexes induced little or no complement fixation. Another source of chemotactic mediators was needed, apparently related to the esterases of the contact system of coagulation. PMID:591003

Leung-Tack, J; Maillard, J; Voisin, G A

1977-01-01

301

Rapid in vitro biocompatibility assay of endovascular stents by flow cytometry using platelet activation and platelet-leukocyte aggregation.  

PubMed

Clinical studies suggest that stent design and surface texture are responsible for differences in biocompatibility of metallic endovascular stents. A simple in vitro experimental setup was established to test stent-induced degree of platelet and leukocyte activation and platelet-leukocyte aggregation by flow cytometry. Heparin-coated tantalum stents and gold-coated and uncoated stainless steel stents were tested. Stents were implanted into silicone tubes and exposed to blood from healthy volunteers. Platelet and leukocyte activation and percentage of leukocyte-platelet aggregates were determined in a whole-blood assay by subsequent staining for activation-associated antigens (CD41a, CD42b, CD62p, and fibrinogen binding) and leukocyte antigens (CD14 and CD45) and flow cytometric analysis. Blood taken directly after venous puncture or exposed to the silicone tube alone was used as negative controls. Positive control was in vitro stimulation with thrombin receptor activating peptide (TRAP-6). Low degree of platelet activation and significant increase in monocyte- and neutrophil-platelet aggregation were observed in blood exposed to stents (P < 0.05). In addition, leukocyte activation was induced as measured by increased CD45 and CD14 expression. Heparin coated stents continuously induced less platelet activation and leukocyte-platelet aggregation than uncoated stainless steel stents of the same length and shorter stents of the same structure. Stent surface coating and texture plays a role in platelet and leukocyte activation and leukocyte-platelet aggregation. Using this simple in vitro assay and whole blood and flow cytometry, it seems possible to differentiate stents by their potency to activate platelets and/or leukocytes. This assay could be applied for improving the biocompatibility of coronary stents. PMID:10088974

Tárnok, A; Mahnke, A; Müller, M; Zotz, R J

1999-02-15

302

Sulfur dioxide attenuates LPS-induced acute lung injury via enhancing polymorphonuclear neutrophil apoptosis  

PubMed Central

Aim: We speculated that the enhanced apoptosis of polymorphonuclear neutrophil (PMN) might be responsible for the inhibition of PMN infiltration in the lung. This study was designed to investigate the effects of sulfur dioxide (SO2) on PMN apoptosis in vivo and in vitro, which may mediate the protective action of SO2 on pulmonary diseases. Methods: Acute lung injury (ALI) was induced by intratracheally instillation of lipopolysaccharide (LPS, 100 ?g/100 g, in 200 ?L saline) in adult male SD rats. SO2 solution (25 ?mol/kg) was administered intraperitoneally 30 min before LPS treatment. The rats were killed 6 h after LPS treatment. Lung tissues were collected for histopathologic study and SO2 concentration assay. Bronchoalveolar lavage fluid (BALF) was collected for the measurement of PMN apoptosis. For in vitro experiments, rat peripheral blood PMNs were cultured and treated with LPS (30 mg/L) and SO2 (10, 20 and 30 ?mol/L) for 6 h, and apoptosis-related protein expression was detected by Western blotting, and apoptosis rate was measured with flow cytometry. Results: LPS treatment significantly reduced the SO2 concentrations in the lung tissue and peripheral blood, as compared with the control group. Pretreatment with SO2 prevented LPS-induced reduction of the SO2 concentration in the lung tissue and peripheral blood. LPS treatment significantly reduced PMN apoptosis both in vivo and in vitro, which could be prevented by the pretreatment with SO2. The protein levels of Caspase-3 and Bax was significantly increased, but Bcl-2 was decreased by the pretreatment with SO2, as compared with LPS administration alone. Conclusion: SO2 plays an important role as the modulator of PMN apoptosis during LPS-induced ALI, which might be one of the mechanisms underlying the protective action of SO2 on pulmonary diseases. PMID:22796764

Ma, Hui-jie; Huang, Xin-li; Liu, Yan; Fan, Ya-min

2012-01-01

303

Exogenous Application of Platelet-Leukocyte Gel during Open Subacromial Decompression Contributes to Improved Patient Outcome  

Microsoft Academic Search

Background: Platelet-leukocyte gel (PLG) is being used during various surgical procedures in an attempt to enhance the healing process. We studied the effects of PLG on postoperative recovery of patients undergoing open subacromial decompression (OSD). Methods: PLG was produced from platelet-leukocyte-rich plasma (P-LRP), prepared from a unit of whole blood. Forty patients were included in the study. Self-assessed evaluations, using

P. A. Everts; R. J. J. Devilee; C. Brown Mahoney; A. van Erp; C. J. M. Oosterbos; M. Stellenboom; J. T. A. Knape; A. van Zundert

2008-01-01

304

Leukocyte glucocorticoid receptor expression and immunoregulation in veterans with and without post-traumatic stress disorder  

Microsoft Academic Search

Post-traumatic stress disorder (PTSD) is associated with a dysregulation of the hypothalamus–pituitary–adrenal axis (HPA axis). In addition, there is evidence for altered glucocorticoid receptor (GR) expression and function in peripheral blood mononuclear cells. The aim of the present study was to differentiate between the effect of trauma exposure and PTSD on leukocyte GR expression and glucocorticoid immune regulation. Leukocyte GR

C S de Kloet; E Vermetten; A Bikker; E Meulman; E Geuze; A Kavelaars; H G M Westenberg; C J Heijnen; CS de Kloet

2007-01-01

305

Fluorescently Activated Cell Sorting Followed by Microarray Profiling of Helper T Cell Subtypes from Human Peripheral Blood  

PubMed Central

Background Peripheral blood samples have been subjected to comprehensive gene expression profiling to identify biomarkers for a wide range of diseases. However, blood samples include red blood cells, white blood cells, and platelets. White blood cells comprise polymorphonuclear leukocytes, monocytes, and various types of lymphocytes. Blood is not distinguishable, irrespective of whether the expression profiles reflect alterations in (a) gene expression patterns in each cell type or (b) the proportion of cell types in blood. CD4+ Th cells are classified into two functionally distinct subclasses, namely Th1 and Th2 cells, on the basis of the unique characteristics of their secreted cytokines and their roles in the immune system. Th1 and Th2 cells play an important role not only in the pathogenesis of human inflammatory, allergic, and autoimmune diseases, but also in diseases that are not considered to be immune or inflammatory disorders. However, analyses of minor cellular components such as CD4+ cell subpopulations have not been performed, partly because of the limited number of these cells in collected samples. Methodology/Principal Findings We describe fluorescently activated cell sorting followed by microarray (FACS–array) technology as a useful experimental strategy for characterizing the expression profiles of specific immune cells in the circulation. We performed reproducible gene expression profiling of Th1 and Th2, respectively. Our data suggest that this procedure provides reliable information on the gene expression profiles of certain small immune cell populations. Moreover, our data suggest that GZMK, GZMH, EOMES, IGFBP3, and STOM may be novel markers for distinguishing Th1 cells from Th2 cells, whereas IL17RB and CNTNAP1 can be Th2-specific markers. Conclusions/Significance Our approach may help in identifying aberrations and novel therapeutic or diagnostic targets for diseases that affect Th1 or Th2 responses and elucidating the involvement of a subpopulation of immune cells in some diseases. PMID:25379667

Ono, Chiaki; Yu, Zhiqian; Kasahara, Yoshiyuki; Kikuchi, Yoshie; Ishii, Naoto; Tomita, Hiroaki

2014-01-01

306

METABOLIC AND MORPHOLOGICAL OBSERVATIONS ON THE EFFECT OF SURFACE-ACTIVE AGENTS ON LEUKOCYTES  

PubMed Central

Morphological and metabolic observations have been made on the effects of endotoxin, deoxycholate, and digitonin (at less than 50 µg/ml) on polymorphonuclear leukocytes and mononuclear cells. The agents stimulate the respiration and glucose oxidation of these cells in a manner similar to that seen during phagocytosis. Electron microscopy revealed no morphological changes with the first two agents, but dramatic membrane changes were seen in the case of digitonin. Here tubular projections of characteristic size and shape formed on and split off the membrane. All the agents stimulated uptake of inulin, but efforts to demonstrate increased pinocytosis by electron microscopy have not so far succeeded, probably due to limitations in present experimental techniques. PMID:6034482

Graham, R. C.; Karnovsky, M. J.; Shafer, A. W.; Glass, E. A.; Karnovsky, Manfred L.

1967-01-01

307

AVIAN POLYMORPHONUCLEAR CELLS CONTRIBUTE TO A DIFFERENTIAL INNATE IMMUNE RESPONSE IN GENETICALLY DEFINED CHICKENS  

Technology Transfer Automated Retrieval System (TEKTRAN)

Heterophils, the primary polymorphonuclear cell (PMN) in chickens, are the avian counterpart to mammalian neutrophils. Heterophils modulate acute innate responses through phagocytosis, respiratory burst, and degranulation. We have been characterizing the heterophil-mediated innate immune response ...

308

Gene Expression Profile of Endotoxin-stimulated Leukocytes of the Term New Born: Control of Cytokine Gene Expression by Interleukin-10  

PubMed Central

Introduction Increasing evidence now supports the association between the fetal inflammatory response syndrome (FIRS) with the pathogenesis of preterm labor, intraventricular hemorrhage and bronchopulmonary dysplasia. Polymorphonuclear leukocyte (PMNs) and mononuclear cell (MONOs) infiltration of the placenta is associated with these disorders. The aim of this study was to reveal cell-specific differences in gene expression and cytokine release in response to endotoxin that would elucidate inflammatory control mechanisms in the newly born. Methods PMNs and MONOs were separately isolated from the same cord blood sample. A genome-wide microarray screened for gene expression and related pathways at 4 h of LPS stimulation (n?=?5). RT-qPCR and ELISA were performed for selected cytokines at 4 h and 18 h of LPS stimulation. Results Compared to PMNs, MONOs had a greater diversity and more robust gene expression that included pro-inflammatory (PI) cytokines, chemokines and growth factors at 4 h. Only MONOs had genes changing expression (all up regulated including interleukin-10) that were clustered in the JAK/STAT pathway. Pre-incubation with IL-10 antibody, for LPS-stimulated MONOs, led to up regulated PI and IL-10 gene expression and release of PI cytokines after 4 h. Discussion The present study suggests a dominant role of MONO gene expression in control of the fetal inflammatory response syndrome at 4 hrs of LPS stimulation. LPS-stimulated MONOs but not PMNs of the newborn have the ability to inhibit PI cytokine gene expression by latent IL-10 release. PMID:23326478

Davidson, Dennis; Zaytseva, Alla; Miskolci, Veronika; Castro-Alcaraz, Susana; Vancurova, Ivana; Patel, Hardik

2013-01-01

309

Leukocyte driven-decidual angiogenesis in early pregnancy  

PubMed Central

Successful pregnancy and long-term, post-natal maternal and offspring cardiac, vascular and metabolic health require key maternal cardiovascular adaptations over gestation. Within the pregnant decidualizing uterus, coordinated vascular, immunological and stromal cell changes occur. Considerable attention has been given to the roles of uterine natural killer (uNK) cells in initiating decidual spiral arterial remodeling, a process normally completed by mid-gestation in mice and in humans. However, leukocyte roles in much earlier, region specific, decidual vascular remodeling are now being defined. Interest in immune cell-promoted vascular remodeling is driven by vascular aberrations that are reported in human gestational complications such as infertility, recurrent spontaneous abortion, preeclampsia (PE) and fetal growth restriction. Appropriate maternal cardiovascular responses during pregnancy protect mothers and their children from later cardiovascular disease risk elevation. One of the earliest uterine responses to pregnancy in species with hemochorial placentation is stromal cell decidualization, which creates unique niches for angiogenesis and leukocyte recruitment. In early decidua basalis, the aspect of the implantation site that will cradle the developing placenta and provide the major blood vessels to support mature placental functions, leukocytes are greatly enriched and display specialized properties. UNK cells, the most abundant leukocyte subset in early decidua basalis, have angiogenic abilities and are essential for normal early decidual angiogenesis. The regulation of uNK cells and their roles in determining maternal and progeny cardiovascular health over pregnancy and postpartum are discussed. PMID:25066422

Lima, Patricia DA; Zhang, Jianhong; Dunk, Caroline; Lye, Stephen J; Anne Croy, B

2014-01-01

310

18F-FDG labelling of human leukocytes.  

PubMed

Radiolabelled leukocytes are useful for the imaging of inflammation and infection, and 18F-fluorodeoxyglucose (18F-FDG) is known to concentrate in metabolically active cells. We evaluated the feasibility of leukocyte labelling with 18F-FDG using ACD and heparin anticoagulants at 20 degrees C and 37 degrees C, with and without gentle mixing during incubation. With leukocytes (WBC) harvested from 20 ml blood, studies were performed using 18F-FDG in concentrations of 3.7-74 MBq (0.1-2.0 mCi). 18F-FDG WBC stability in platelet-poor plasma was assessed at 1-4 h. Satisfactory labelling efficiency was achieved with incubation in heparin-saline at 37 degrees C for 30 min (62.7+/-1.6%), and was further enhanced by mixing during incubation (78.1+/-3.9%). Cell labelling was predominantly of granulocytes (78.5+/-1.4%). 18F-FDG WBC was relatively stable in platelet-poor plasma for up to 4 h, and no cell staining was observed in viability studies using trypan blue. These results indicate the feasibility of leukocyte labelling with 18F-FDG, providing an approach that may be useful in PET imaging of inflammation and infection. PMID:10994674

Forstrom, L A; Mullan, B P; Hung, J C; Lowe, V J; Thorson, L M

2000-07-01

311

Leukocyte margination at arteriole shear rate  

PubMed Central

Abstract We numerically investigated margination of leukocytes at arteriole shear rate in straight circular channels with diameters ranging from 10 to 22 ?m. Our results demonstrated that passing motion of RBCs effectively induces leukocyte margination not only in small channels but also in large channels. A longer time is needed for margination to occur in a larger channel, but once a leukocyte has marginated, passing motion of RBCs occurs continuously independent of the channel diameter, and leukocyte margination is sustained for a long duration. We also show that leukocytes rarely approach the wall surface to within a microvillus length at arteriole shear rate. PMID:24907300

Takeishi, Naoki; Imai, Yohsuke; Nakaaki, Keita; Yamaguchi, Takami; Ishikawa, Takuji

2014-01-01

312

A model of canine leukocyte telomere dynamics.  

PubMed

Recent studies have found associations of leukocyte telomere length (TL) with diseases of aging and with longevity. However, it is unknown whether birth leukocyte TL or its age-dependent attrition--the two factors that determine leukocyte TL dynamics--explains these associations because acquiring this information entails monitoring individuals over their entire life course. We tested in dogs a model of leukocyte TL dynamics, based on the following premises: (i) TL is synchronized among somatic tissues; (ii) TL in skeletal muscle, which is largely postmitotic, is a measure of TL in early development; and (iii) the difference between TL in leukocytes and muscle (?LMTL) is the extent of leukocyte TL shortening since early development. Using this model, we observed in 83 dogs (ages, 4-42 months) no significant change with age in TLs of skeletal muscle and a shorter TL in leukocytes than in skeletal muscle (P<0.0001). Age explained 43% of the variation in ?LMTL (P<0.00001), but only 6% of the variation in leukocyte TL (P=0.035) among dogs. Accordingly, muscle TL and ?LMTL provide the two essential factors of leukocyte TL dynamics in the individual dog. When applied to humans, the partition of the contribution of leukocyte TL during early development vs. telomere shortening afterward might provide information about whether the individual's longevity is calibrated to either one or both factors that define leukocyte TL dynamics. PMID:21917112

Benetos, Athanase; Kimura, Masayuki; Labat, Carlos; Buchoff, Gerald M; Huber, Shell; Labat, Laura; Lu, Xiaobin; Aviv, Abraham

2011-12-01

313

The effect of citrus-derived oil on bovine blood neutrophil function and gene expression in vitro.  

PubMed

Research on the use of natural products to treat or prevent microbial invasion as alternatives to antibiotic use is growing. Polymorphonuclear leukocytes (PMNL) play a vital role with regard to the innate immune response that affects severity or duration of mastitis. To our knowledge, effect of cold-pressed terpeneless Valencia orange oil (TCO) on bovine PMNL function has not been elucidated. Therefore, the objective of this study was to investigate the effect of TCO on bovine blood PMNL chemotaxis and phagocytosis capabilities and the expression of genes involved in inflammatory response in vitro. Polymorphonuclear leukocytes were isolated from jugular blood of 12 Holstein cows in mid-lactation and were incubated with 0.0 or 0.01% TCO for 120min at 37°C and 5% CO2, and phagocytosis (2×10(6) PMNL) and chemotaxis (6×10(6) PMNL) assays were then performed in vitro. For gene expression, RNA was extracted from incubated PMNL (6×10(6) PMNL), and gene expression was analyzed using quantitative PCR. The supernatant was stored at -80°C for analysis of tumor necrosis factor-?. Data were analyzed using a general linear mixed model with cow and treatment (i.e., control or TCO) in the model statement. In vitro supplementation of 0.01% of TCO increased the chemotactic ability to IL-8 by 47%; however, migration of PMNL to complement 5a was not altered. Treatment did not affect the production of tumor necrosis factor-? by PMNL. Expression of proinflammatory genes (i.e., SELL, TLR4, IRAK1, TRAF6, and LYZ) coding for proteins was not altered by incubation of PMNL with TCO. However, downregulation of TLR2 [fold change (FC=treatment/control)=-2.14], NFKBIA (FC=1.82), IL1B (FC=-2.16), TNFA (FC=-9.43), and SOD2 (FC=-1.57) was observed for PMNL incubated with TCO when compared with controls. Interestingly, expression of IL10, a well-known antiinflammatory cytokine, was also downregulated (FC=-3.78), whereas expression of IL8 (FC=1.93), a gene coding for the cytokine IL-8 known for its chemotactic function, tended to be upregulated in PMNL incubated with TCO. Incubation of PMNL with TCO enhanced PMNL chemotaxis in vitro. The expression of genes involved in the inflammatory response was primarily downregulated. Results showed that 0.01% TCO did not impair the function of PMNL in vitro. Future studies investigating the use of TCO as an alternative therapy for treatment of mastitis, including dose and duration, for cows during lactation are warranted. PMID:25434342

Garcia, M; Elsasser, T H; Biswas, D; Moyes, K M

2015-02-01

314

Role of leukocyte elastase in preventing cellular re-colonization of the mural thrombus.  

PubMed

To explore possible mechanisms responsible for the absence of cell re-colonization of mural thrombi in aneurysms, we analyzed the release and storage of leukocyte proteases in the most luminal layer versus intermediate and abluminal layers of 10 mural thrombi of human abdominal aortic aneurysms. The luminal layer contained many polymorphonuclear leukocytes (PMNs), which released pro-matrix metalloproteinase (MMP)-9 and MMP-8. Leukocyte elastase was also stored and released by the luminal layer (immunohistochemistry, activity on synthetic substrates, and casein zymography). Acid buffer allowed extraction of leukocyte elastase from the luminal layer, which was inhibited by elastase inhibitors. Casein zymography of luminal extracts and conditioned medium from formyl-methionyl-leucyl-phenylalanine (fMLP)-stimulated PMNs exhibited a similar lysis pattern, corresponding to elastase activity. Smooth muscle cell (SMC) seeding resulted in colonization of the intermediate thrombus layer ex vivo but not of the luminal layer. Extracts of the luminal layer induced loss of anchorage of both cultured human smooth muscle cells and stromal cells of bone marrow origin (anoikis). This anoikis was prevented by preincubation of the extracts with serine protease inhibitors. Moreover, adhesion of human SMCs and stromal bone marrow cells on fibrin gels was strongly inhibited when the gel was preincubated with pure elastase, medium of fMLP-stimulated PMNs, or extracts of luminal layers of mural thrombi. This loss of cell anchorage was prevented by the preincubation of the medium or extracts with alpha(1)-antitrypsin, but not when alpha(1)-antitrypsin was added after binding of elastase to the fibrin gel. In conclusion, elastase released by PMNs trapped within the mural thrombus impairs the spontaneous anchorage of mesenchymal cells to a fibrin matrix. This phenomenon could be one mechanism by which cellular healing of the mural thrombus in aneurysms is prevented. PMID:15161642

Fontaine, Vincent; Touat, Ziad; Mtairag, El Mostafa; Vranckx, Roger; Louedec, Liliane; Houard, Xavier; Andreassian, Bernard; Sebbag, Uriel; Palombi, Tonino; Jacob, Marie-Paule; Meilhac, Olivier; Michel, Jean-Baptiste

2004-06-01

315

Concanavalin A as a probe for studying the mechanism of metabolic stimulation of leukocytes.  

PubMed

The disruption of the molecular organization of the plasma membrane of leukocytes by phagocytosable particles, or by agents such as surfactants, antibodies, phospholipase C, fatty acids and chemotactic factors, leads to a stimulation of the phagocyte oxidative metabolism. Concanavalin A (Con A) has been used as a tool to study the mechanism of this metabolic regulation. The binding of Con A to the surface of polymorphonuclear leukocytes (PMNL) or macrophages produces a rapid enhancement of oxygen uptake and glucose oxidation through the hexose monophosphate pathway (HMP). This is explained by an activation of the granular NADPH oxidase, the key enzyme in the metabolic stimulation. The effect of Con A is not due to endocytosed lectin, since Con A covalently coupled to large sepharose beads still acts as stimulant. The metabolic changes caused by Con A are reversible. If, after the onset of stimulation, sugars with high affinity for Con A are added to the leukocyte suspension, the activity of granular NADPH oxidase and the rate of respiration and glucose oxidation return to their resting values. The metabolic burst, while partially supressed by treatment of PMNL with iodoacetate, sodium flouride and cytochalasin B, is slightly increased by colchicine. Con A induces a selective release of granular enzymes (beta-glucuronidase, peroxidase, alkaline phosphatase) from PMNL, whereas no leakage of cytoplasmic enzymes is observed. The enzyme release is inhibited by iodoacetate and by drugs known to increase cell levels of cyclic AMP. Based on a current view of the mode of interaction between Con A and cell surfaces, a model of the metabolic disruption of leukocytes is presented. PMID:168745

Romeo, D; Zabucchi, G; Jug, M; Miani, N; Soranzo, M R

1975-01-01

316

Channel catfish (Ictalurus punctatus) leukocytes express estrogen receptor isoforms ER? and ER?2 and are functionally modulated by estrogens  

USGS Publications Warehouse

Estrogens are recognized as modulators of immune responses in mammals and teleosts. While it is known that the effects of estrogens are mediated via leukocyte-specific estrogen receptors (ERs) in humans and mice, leucocyte-specific estrogen receptor expression and the effects of estrogens on this cell population is less explored and poorly understood in teleosts. Here in, we verify that channel catfish (Ictalurus punctaus) leukocytes express ER? and ER?2. Transcripts of these isoforms were detected in tissue-associated leukocyte populations by PCR, but ER?2 was rarely detected in PBLs. Expression of these receptors was temporally regulated in PBLs following polyclonal activation by concanavalin A, lipopolysaccharide or alloantigen based on evaluation by quantitative and end-point PCR. Examination of long-term leukocyte cell lines demonstrated that these receptors are differentially expressed depending on leukocyte lineage and phenotype. Expression of ERs was also temporally dynamic in some leukocyte lineages and may reflect stage of cell maturity. Estrogens affect the responsiveness of channel catfish peripheral blood leukocytes (PBLs) to mitogens in vitro. Similarly, bactericidal activity and phorbol 12-myristate 13-acetate induced respiratory burst was modulated by 17?-estradiol. These actions were blocked by the pure ER antagonist ICI 182780 indicating that response is, in part, mediated via ER?. In summary, estrogen receptors are expressed in channel catfish leukocytes and participate in the regulation of the immune response. This is the first time leukocyte lineage expression has been reported in teleost cell lines.

Iwanowicz, Luke R.; Stafford, James L.; Patiño, Reynaldo; Bengten, Eva; Miller, Norman W.; Blazer, Vicki S.

2014-01-01

317

Channel catfish (Ictalurus punctatus) leukocytes express estrogen receptor isoforms ER? and ER?2 and are functionally modulated by estrogens.  

PubMed

Estrogens are recognized as modulators of immune responses in mammals and teleosts. While it is known that the effects of estrogens are mediated via leukocyte-specific estrogen receptors (ERs) in humans and mice, leucocyte-specific estrogen receptor expression and the effects of estrogens on this cell population is less explored and poorly understood in teleosts. Here in, we verify that channel catfish (Ictalurus punctaus) leukocytes express ER? and ER?2. Transcripts of these isoforms were detected in tissue-associated leukocyte populations by PCR, but ER?2 was rarely detected in PBLs. Expression of these receptors was temporally regulated in PBLs following polyclonal activation by concanavalin A, lipopolysaccharide or alloantigen based on evaluation by quantitative and end-point PCR. Examination of long-term leukocyte cell lines demonstrated that these receptors are differentially expressed depending on leukocyte lineage and phenotype. Expression of ERs was also temporally dynamic in some leukocyte lineages and may reflect stage of cell maturity. Estrogens affect the responsiveness of channel catfish peripheral blood leukocytes (PBLs) to mitogens in vitro. Similarly, bactericidal activity and phorbol 12-myristate 13-acetate induced respiratory burst was modulated by 17?-estradiol. These actions were blocked by the pure ER antagonist ICI 182780 indicating that response is, in part, mediated via ER?. In summary, estrogen receptors are expressed in channel catfish leukocytes and participate in the regulation of the immune response. This is the first time leukocyte lineage expression has been reported in teleost cell lines. PMID:24973517

Iwanowicz, Luke R; Stafford, James L; Patiño, Reynaldo; Bengten, Eva; Miller, Norman W; Blazer, Vicki S

2014-09-01

318

Comparison of the relative telomere length measured in leukocytes and eleven different human tissues.  

PubMed

The relative length of telomeres measured in peripheral blood leukocytes is a commonly used system marker for biological aging and can also be used as a biomarker of cardiovascular aging. However, to what extent the telomere length in peripheral leukocytes reflects telomere length in different organ tissues is still unclear. Therefore, we have measured relative telomere length (rTL) in twelve different human tissues (peripheral blood leukocytes, liver, kidney, heart, spleen, brain, skin, triceps, tongue mucosa, intercostal skeletal muscle, subcutaneous fat, and abdominal fat) from twelve cadavers (age range of 29 week of gestation to 88 years old). The highest rTL variability was observed in peripheral leukocytes, and the lowest variability was found in brain. We found a significant linear correlation between leukocyte rTL and both intercostal muscle (R=0.68, P<0.02) and liver rTL (R=0.60, P<0.05) only. High rTL variability was observed between different organs from one individual. Furthermore, we have shown that even slight DNA degradation (modeled by sonication of genomic DNA) leads to false rTL shortening. We conclude that the rTL in peripheral leukocytes is not strongly correlated with the rTL in different organs. PMID:25428739

Dlouha, D; Maluskova, J; Kralova Lesna, I; Lanska, V; Hubacek, J A

2014-01-01

319

[Changes of peripheral leukocyte-counts by electrically induced convulsion in rabbits (author's transl)].  

PubMed

Effects of electrically induced convulsion (EIC) in rabbits on peripheral leukocyte-count levels were studied. (1) Leukocyte-counts increased immediately after the EIC (phase-1) and 4 hours later (phase-2). In the examination of blood smear, phase-2 involved the shift to the left in neutrophils. This biphasic curve also showed by administration of convulsants. (2) Both phase-1 and the rise of transitory blood pressure disappeared by muscle relaxation. (3) Immediately after EIC, the circulating blood volume was significantly higher (about 7%, P less than .001) and the hematocrit was also higher. (4) Phase-1 was not affected by selective destruction of adrenergic nerve terminal with 6-hydroxydopamine (6-OHDA). Although, phase-2 was diminished by treatment with both 6-OHDA and reserpine. (5) An increase in leukocyte-counts occurred on the administration of serum obtained from rabbit during phase-2. These results seem to indicate that phase-1 occurs when circulating blood volume is higher due to convulsive muscle construction and thereby marginated granulocytes appear into the circulating blood. Aslo, it might be expected that phase-2 occurs chiefly by mobilizing of leukocytes from the storage pool in the bone marrow into the circulating blood by the humoral factor. PMID:1241866

Toyosawa, K

1975-01-01

320

Single and repeated moderate consumption of native or dealcoholized red wine show different effects on antioxidant parameters in blood and DNA strand breaks in peripheral leukocytes in healthy volunteers: a randomized controlled trial [ISRCTN68505294  

PubMed Central

Background Red wine (RW) is rich in antioxidant polyphenols that might protect from oxidative stress related diseases, such as cardiovascular disease and cancer. Antioxidant effects after single ingestion of RW or dealcoholized RW (DRW) have been observed in several studies, but results after regular consumption are contradictory. Thus, we examined if single or repeated consumption of moderate amounts of RW or DRW exert antioxidant activity in vivo. Methods Total phenolic content and concentration of other antioxidants in plasma/serum, total antioxidant capacity (TEAC) in plasma as well as DNA strand breaks in peripheral leukocytes were measured in healthy non-smokers A) before, 90 and 360 min after ingestion of one glass of RW, DRW or water; B) before and after consumption of one glass of RW or DRW daily for 6 weeks. DNA strand breaks (SB) were determined by single cell gel electrophoresis (Comet Assay) in untreated cells and after induction of oxidative stress ex vivo with H2O2 (300 ?M, 20 min). Results Both RW and DRW transiently increased total phenolic content in plasma after single consumption, but only RW lead to a sustained increase if consumed regularly. Plasma antioxidant capacity was not affected by single or regular consumption of RW or DRW. Effects of RW and DRW on DNA SB were conflicting. DNA strand breaks in untreated cells increased after a single dose of RW and DRW, whereas H2O2 induced SB were reduced after DRW. In contrast, regular RW consumption reduced SB in untreated cells but did not affect H2O2 induced SB. Conclusion The results suggest that consumption of both RW and DRW leads to an accumulation of phenolic compounds in plasma without increasing plasma antioxidant capacity. Red wine and DRW seem to affect the occurrence of DNA strand breaks, but this cannot be referred to antioxidant effects. PMID:16287499

Arendt, Bianca M; Ellinger, Sabine; Kekic, Klaudia; Geus, Leonie; Fimmers, Rolf; Spengler, Ulrich; Müller, Wolfgang-Ulrich; Goerlich, Roland

2005-01-01

321

Appearance of acute gouty arthritis on indium-111-labeled leukocyte scintigraphy  

SciTech Connect

Indium-111-labeled leukocyte scintigraphy was performed on a 66-yr-old male with polyarticular acute gouty arthritis. Images revealed intense labeled leukocyte accumulation in a pattern indistinguishable from septic arthritis, in both knees and ankles, and the metatarsophalangeal joint of both great toes, all of which were involved in the acute gouty attack. Joint aspirate as well as blood cultures were reported as no growth; the patient was treated with intravenous colchicine and ACTH for 10 days with dramatic improvement noted. Labeled leukocyte imaging, repeated 12 days after the initial study, revealed near total resolution of joint abnormalities, concordant with the patient's clinical improvement. This case demonstrates that while acute gouty arthritis is a potential pitfall in labeled leukocyte imaging, in the presence of known gout, it may provide a simple, objective, noninvasive method of evaluating patient response to therapy.

Palestro, C.J.; Vega, A.; Kim, C.K.; Swyer, A.J.; Goldsmith, S.J. (Mt. Sinai Medical Center, New York, NY (USA))

1990-05-01

322

Leukocyte chemoattractant receptors in human disease pathogenesis.  

PubMed

Combinations of leukocyte attractant ligands and cognate heptahelical receptors specify the systemic recruitment of circulating cells by triggering integrin-dependent adhesion to endothelial cells, supporting extravasation, and directing specific intratissue localization via gradient-driven chemotaxis. Chemoattractant receptors also control leukocyte egress from lymphoid organs and peripheral tissues. In this article, we summarize the fundamental mechanics of leukocyte trafficking, from the evolution of multistep models of leukocyte recruitment and navigation to the regulation of chemoattractant availability and function by atypical heptahelical receptors. To provide a more complete picture of the migratory circuits involved in leukocyte trafficking, we integrate a number of nonchemokine chemoattractant receptors into our discussion. Leukocyte chemoattractant receptors play key roles in the pathogenesis of autoimmune diseases, allergy, inflammatory disorders, and cancer. We review recent advances in our understanding of chemoattractant receptors in disease pathogenesis, with a focus on genome-wide association studies in humans and the translational implications of mechanistic studies in animal disease models. PMID:25387059

Zabel, Brian A; Rott, Alena; Butcher, Eugene C

2015-01-24

323

Postprandial leukocyte increase in healthy subjects  

Microsoft Academic Search

Atherosclerosis is an inflammatory disorder involving leukocytes and lipids. To study the relationship between leukocytes and lipids in vivo, leukocyte changes were determined in 14 healthy males (age, 23 [plusmn] 3 years; body mass index [BMI], 21.9 [plusmn] 1.5 kg\\/m2) after an 8-hour oral fat load (50 g\\/m2) and after water. The postprandial triglyceride (TG) increment after fat was paralleled

A. J. H. H. M. van Oostrom; T. P. Sijmonsma; T. J. Rabelink; B. S. van Asbeck; M. Castro Cabezas

2003-01-01

324

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

PubMed

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 IL1?, IL6, TNF?, IL12, IL10, IL4, TGF?1, 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 IL1? (p = 0.046) and TNF? (p = 0.016) were detected for the CaP surfaces compared to AB/AE surface only. The levels of IL4, IL10, and TGF?1 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 (IL1? and TNF?) on these surfaces. PMID:23598427

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

325

Mechanism underlying levofloxacin uptake by human polymorphonuclear neutrophils.  

PubMed

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 Ca(2+)-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

Vazifeh, D; Bryskier, A; Labro, M T

1999-02-01

326

Leukocyte-depleted reperfusion after long cardioplegic arrest attenuates ischemia–reperfusion injury of the coronary endothelium and myocardium in rabbit hearts  

Microsoft Academic Search

Objective: Cardiopulmonary bypass activates leukocytes, which should injure the coronary endothelium and myocardium during reperfusion especially after long cardioplegic arrest with long cardiopulmonary bypass time. The present study was designed to determine the protective efficacy of leukocyte-depleted reperfusion in blood-perfused parabiotic isolated rabbit hearts as a surgically relevant model with long cardioplegic arrest. Methods: Each isolated rabbit heart, with a

Yukio Okazaki; Zhi-Li Cao; Satoshi Ohtsubo; Masakatsu Hamada; Kozo Naito; Kazuhisa Rikitake; Masafumi Natsuaki; Tsuyoshi Itoh

2000-01-01

327

Spermadhesin PSP-I/PSP-II heterodimer induces migration of polymorphonuclear neutrophils into the uterine cavity of the sow.  

PubMed

Seminal plasma (SP) is a complex fluid which exerts biological actions in the female reproductive tract. In pigs, SP elicits endometrial inflammation and consequent immune changes after mating. This study tested whether heparin-binding spermadhesins (HBPs) and the heterodimer of porcine sperm adhesions I and II (PSP-I/PSP-II) in SP recruit different lymphocyte subsets (CD2(+), CD4(+) and CD8(+) T cells) or polymorphonuclear leukocytes (PMNs) to the superficial endometrium or luminal epithelium and lumen, respectively, of oestrous sows. In Experiment 1, endometrial biopsies were taken between 2 and 120 min after infusion of uterine horns with HBPs, PSP-I/PSP-II or saline and evaluated by immunohistochemistry or histology. In Experiment 2, the uterus of oestrous sows was infused with PSP-I/PSP-II or saline to assess PMN numbers in the uterine lumen 3h later. PSP-I/PSP-II elicited CD2+ T cell recruitment from 10 min, and CD8(+) T cells from 60 min after infusion, while HBPs increased CD4(+) T cell recruitment by 120 min. PSP-I/PSP-II but not HBPs induced PMN migration to the surface epithelium by 10 min. PMN numbers were elevated 5-fold by 30 min and 7-fold from 60 min, with PMNs detectable in the lumen from 30 min after infusion. Six-fold more PMNs were collected from the uterine lumen of PSP-I/PSP-II-infused sows compared to controls at 3h after infusion. These data show that PSP-I/PSP-II heterodimer in seminal plasma has a predominant role in triggering the recruitment of uterine PMNs and T cells after mating, initiating a cascade of transient and long-lasting immunological events. PMID:19948361

Rodriguez-Martinez, H; Saravia, F; Wallgren, M; Martinez, E A; Sanz, L; Roca, J; Vazquez, J M; Calvete, J J

2010-01-01

328

Exercise-induced leukocyte apoptosis.  

PubMed

Physical exercise is well known to affect leukocyte numbers and function. While regular exercise training has been shown to enhance specific immune functions, acute bouts of intensive exercise often lead to a pro-inflammatory response accompanied by a transient lymphocytopenia and neutrophilia. It can be assumed, that lymphocytopenia can be attributed at least partially to an enhanced lymphocyte apoptosis. In contrast, regulation of neutrophil apoptosis after exercise remains controversial since studies demonstrated both an up-regulation as well as a down-regulation of cell death. However, these discrepancies may be due to differences in exercise protocols, subjects' fitness levels, and to different methodological approaches. Two major signalling pathways of exercise induced apoptosis have been identified. First the external receptor mediated pathway using death receptors, and second the internal, oxidative-mediated pathway which encompasses the mitochondria. Potential apoptosis modulating mediators are reactive oxygen species (ROS), glucocorticoids and cytokines which are part of the systemic inflammatory response evoked after acute intensive exercise. Finally, the physiological impact and clinical relevance of leukocyte apoptosis will be discussed. On the one hand, exercise-induced apoptosis might be a mechanism to remove activated and potentially autoreactive immune cells. On the other hand, apoptosis might be a regulatory mechanism which is necessary for tissue reorganization and adaptational training processes. PMID:24974724

Krüger, Karsten; Mooren, Frank C

2014-01-01

329

Non-specific cytotoxic activity of teleost leukocytes.  

PubMed

The existence of lymphoid cells with "natural" killer activity in mammals and birds has been known for some time. Several previous reports have demonstrated similar activity in carp and catfish kidney leukocytes. However, the activity previously reported was directed towards established mammalian cell lines. In this report we confirm the existence of spontaneous killer activity in other species of teleosts, including salmonids. This spontaneous cytotoxic activity is directed towards several established teleost, as well as mammalian, cell lines. Cytotoxic activity appears to be optimal at 20 degrees C in an 8 hour 51Cr release assay. The RTG-2, AS, GS and EPC cell lines of teleost origin are susceptible to lysis by kidney, spleen, and blood leukocytes of Salmo salar, Salmo gairdneri, and Notemigonus crysoleucas. Furthermore, the susceptibility of the RTG-2 and AS teleost cell lines to killing by kidney leukocytes of both S. salar and S. gairdneri was significantly enhanced by preinfection of the target cells with infectious pancreatic necrosis virus. PMID:3996708

Moody, C E; Serreze, D V; Reno, P W

1985-01-01

330

Association of circulating leukocyte count with coronary atherosclerosis regression after pravastatin treatment.  

PubMed

Epidemiological studies have demonstrated that the peripheral blood leukocyte count could be used as a marker of the progression of atherosclerosis. Few data exist regarding the relationship between inhibition of the progression of coronary atherosclerosis and the anti-inflammatory effects of statins, especially the drugs' effects on the leukocyte count in patients with coronary artery disease. A 6-month prospective study was, therefore, conducted in 50 patients treated with pravastatin. The plaque volume, as assessed by volumetric analysis using intravascular ultrasound, reduced significantly by 14% (p<0.0001, vs. baseline) following the treatment, furthermore, a corresponding decrease of the leukocyte count (8.9%, p<0.01, vs. baseline) was also seen. No correlation was found between the change in the leukocyte count and any of the changes in the lipid levels; changes in either of these are known to be associated with the rate of progression of atherosclerosis. A multivariate regression analysis using other traditional risk factors and medications as covariates revealed that the decrease in the leukocyte count was an independent predictor of inhibition of the progression of coronary atherosclerosis. In conclusion, a reduction of the leukocyte count as one of the non-lipid-lowering effects of pravastatin may be a novel marker of regression of coronary atherosclerosis. PMID:18374337

Tani, Shigemasa; Nagao, Ken; Anazawa, Takeo; Kawamata, Hirofumi; Iida, Kiyoshi; Matsumoto, Michiaki; Sato, Yuichi; Hirayama, Atsushi

2008-06-01

331

Recoil and Stiffening by Adherent Leukocytes in Response to Fluid Shear?  

PubMed Central

Abstract Prolonged exposure to fluid shear stress alters leukocyte functions associated with the immune response. We examined the initial response of freshly isolated human leukocytes to fluid shear stress under high magnification. Adherent leukocytes exhibit a rapid biomechanical response to physiological levels of fluid shear stress. After passive displacement in the direction of a constant fluid shear stress, adherent leukocytes actively recoil back in the opposite direction of the fluid flow. Recoil is observed within seconds of the applied fluid shear stress. Simultaneously, fluid shear stress induces a stiffening of the cell. The immediate cell displacement in response to a step increase in fluid shear stress is greatly attenuated in subsequent steps compared to the initial fluid shear stress step. Recoil is not mediated by actin polymerization-dependent mechanisms, as cytochalasin D had no effect on this early response. However, stiffening was determined in part by an intact actin cytoskeleton. Inhibiting myosin force generation with ML-7 abolished the recoil and stiffening responses, implicating force generation by myosin as an important contributor to the early leukocyte response to fluid shear stress. This initial shear stress response may be particularly important in facilitating leukocyte attachment under sustained fluid shear stress by the flowing blood in the microcirculation. PMID:17921217

Coughlin, Mark F.; Sohn, David D.; Schmid-Schönbein, Geert W.

2008-01-01

332

How chemokines invite leukocytes to dance  

Microsoft Academic Search

A prominent activity of the chemokine system is the regulation of leukocyte trafficking. Here we summarize recent findings on the initial steps in chemokine receptor–induced signal transduction in leukocytes. In particular, we discuss the potential influences of the formation of oligomers of ligand and receptor and of coupling between chemokine signals and regulators of the cytoskeleton, such as small GTPases.

Marcus Thelen; Jens V Stein

2008-01-01

333

Isolation and Analysis of Brain-sequestered Leukocytes from Plasmodium berghei ANKA-infected Mice  

PubMed Central

We describe a method for isolation and characterization of adherent inflammatory cells from brain blood vessels of P. berghei ANKA-infected mice. Infection of susceptible mouse-strains with this parasite strain results in the induction of experimental cerebral malaria, a neurologic syndrome that recapitulates certain important aspects of Plasmodium falciparum-mediated severe malaria in humans 1,2 . Mature forms of blood-stage malaria express parasitic proteins on the surface of the infected erythrocyte, which allows them to bind to vascular endothelial cells. This process induces obstructions in blood flow, resulting in hypoxia and haemorrhages 3 and also stimulates the recruitment of inflammatory leukocytes to the site of parasite sequestration. Unlike other infections, i.e neutrotopic viruses4-6, both malaria-parasitized red blood cells (pRBC) as well as associated inflammatory leukocytes remain sequestered within blood vessels rather than infiltrating the brain parenchyma. Thus to avoid contamination of sequestered leukocytes with non-inflammatory circulating cells, extensive intracardial perfusion of infected-mice prior to organ extraction and tissue processing is required in this procedure to remove the blood compartment. After perfusion, brains are harvested and dissected in small pieces. The tissue structure is further disrupted by enzymatic treatment with Collagenase D and DNAse I. The resulting brain homogenate is then centrifuged on a Percoll gradient that allows separation of brain-sequestered leukocytes (BSL) from myelin and other tissue debris. Isolated cells are then washed, counted using a hemocytometer and stained with fluorescent antibodies for subsequent analysis by flow cytometry. This procedure allows comprehensive phenotypic characterization of inflammatory leukocytes migrating to the brain in response to various stimuli, including stroke as well as viral or parasitic infections. The method also provides a useful tool for assessment of novel anti-inflammatory treatments in pre-clinical animal models. PMID:23329000

Ryg-Cornejo, Victoria; Ioannidis, Lisa J.; Hansen, Diana S.

2013-01-01

334

Endogenous Thrombospondin-1 Regulates Leukocyte Recruitment and Activation and Accelerates Death from Systemic Candidiasis  

PubMed Central

Disseminated Candida albicans infection results in high morbidity and mortality despite treatment with existing antifungal drugs. Recent studies suggest that modulating the host immune response can improve survival, but specific host targets for accomplishing this goal remain to be identified. The extracellular matrix protein thrombospondin-1 is released at sites of tissue injury and modulates several immune functions, but its role in C. albicans pathogenesis has not been investigated. Here, we show that mice lacking thrombospondin-1 have an advantage in surviving disseminated candidiasis and more efficiently clear the initial colonization from kidneys despite exhibiting fewer infiltrating leukocytes. By examining local and systemic cytokine responses to C. albicans and other standard inflammatory stimuli, we identify a crucial function of phagocytes in this enhanced resistance. Subcutaneous air pouch and systemic candidiasis models demonstrated that endogenous thrombospondin-1 enhances the early innate immune response against C. albicans and promotes activation of inflammatory macrophages (inducible nitric oxide synthase+, IL-6high, TNF-?high, IL-10low), release of the chemokines MIP-2, JE, MIP-1?, and RANTES, and CXCR2-driven polymorphonuclear leukocytes recruitment. However, thrombospondin-1 inhibited the phagocytic capacity of inflammatory leukocytes in vivo and in vitro, resulting in increased fungal burden in the kidney and increased mortality in wild type mice. Thus, thrombospondin-1 enhances the pathogenesis of disseminated candidiasis by creating an imbalance in the host immune response that ultimately leads to reduced phagocytic function, impaired fungal clearance, and increased mortality. Conversely, inhibitors of thrombospondin-1 may be useful drugs to improve patient recovery from disseminated candidiasis. PMID:23144964

Martin-Manso, Gema; Navarathna, Dhammika H. M. L. P.; Galli, Susana; Soto-Pantoja, David R.; Kuznetsova, Svetlana A.; Tsokos, Maria; Roberts, David D.

2012-01-01

335

Changes in the Phagocytic Activity of Polyrnorphonuclear Leukocytes following Total Body X-Irradiation in the Rat  

Microsoft Academic Search

W HILE X-IRRADIATION ins sufficienst. dosage will depress the number of circulating leukocytes, little is kmsowns about its effect omsthe functions of those few leukocytes which constimsue to be formed amid delivered to the blood stream. Durimsg histologic studies ons the lymph msodes of rabbits exposed to 600 r or 800 r x-irradiatiots and sacrificed at instervals up to twensty-four

I. WILKINSON

336

Maternal circulating leukocytes display early chemotactic responsiveness during late gestation  

PubMed Central

Background Parturition has been widely described as an immunological response; however, it is unknown how this is triggered. We hypothesized that an early event in parturition is an increased responsiveness of peripheral leukocytes to chemotactic stimuli expressed by reproductive tissues, and this precedes expression of tissue chemotactic activity, uterine activation and the systemic progesterone/estradiol shift. Methods Tissues and blood were collected from pregnant Long-Evans rats on gestational days (GD) 17, 20 and 22 (term gestation). We employed a validated Boyden chamber assay, flow cytometry, quantitative real time-polymerase chain reaction, and enzyme-linked immunosorbent assays. Results We found that GD20 maternal peripheral leukocytes migrated more than those from GD17 when these were tested with GD22 uterus and cervix extracts. Leukocytes on GD20 also displayed a significant increase in chemokine (C-C motif) ligand 2 (Ccl2) gene expression and this correlated with an increase in peripheral granulocyte proportions and a decrease in B cell and monocyte proportions. Tissue chemotactic activity and specific chemokines (CCL2, chemokine (C-X-C motif) ligand 1/CXCL1, and CXCL10) were mostly unchanged from GD17 to GD20 and increased only on GD22. CXCL10 peaked on GD20 in cervical tissues. As expected, prostaglandin F2? receptor and oxytocin receptor gene expression increased dramatically between GD20 and 22. Progesterone concentrations fell and estradiol-17? concentrations increased in peripheral serum, cervical and uterine tissue extracts between GD20 and 22. Conclusion Maternal circulating leukocytes display early chemotactic responsiveness, which leads to their infiltration into the uterus where they may participate in the process of parturition. PMID:23445935

2013-01-01

337

Mechanics of Leukocyte Deformation and Adhesion to Endothelium in Shear Flow  

Microsoft Academic Search

The mechanics of leukocyte [white blood cell (WBC)] deformation and adhesion to endothelial cells (EC) in shear flow has been investigated. Experimental data on transient WBC–EC adhesion were obtained from in vivo measurements. Microscopic images of WBC–EC contact during incipient WBC rolling revealed that for a given wall shear stress, the contact area increases with time as new bonds are

Cheng Dong; Jian Cao; Erika J. Struble; Herbert H. Lipowsky

1999-01-01

338

A Genome-Wide Gene Expression Signature of Environmental Geography in Leukocytes of Moroccan Amazighs  

Microsoft Academic Search

The different environments that humans experience are likely to impact physiology and disease susceptibility. In order to estimate the magnitude of the impact of environment on transcript abundance, we examined gene expression in peripheral blood leukocyte samples from 46 desert nomadic, mountain agrarian and coastal urban Moroccan Amazigh individuals. Despite great expression heterogeneity in humans, as much as one third

Youssef Idaghdour; John D. Storey; Sami J. Jadallah; Greg Gibson

2008-01-01

339

Effect of Topical Nipradilol on Retinal Microvascular Leukocyte Adhesion in Diabetic Rats  

Microsoft Academic Search

Background: Retinal leukostasis plays an important role in the pathogenesis of diabetic retinopathy. Objectives: We studied the effects of nipradilol, a topical antiglaucoma ??-blocker and nitric oxide donor, on the retinal vascular leukocyte adhesion of rats with diabetes. Methods: Diabetes was induced in seven Brown-Norway rats by one intravenous injection (65 mg\\/kg) of streptozotocin and confirmed by blood glucose levels

Ryuichiro Ono; Akihiro Kakehashi; Yuka Ito; Norito Sugi; Shinji Makino; Eiji Kobayashi; Yoji Hakamada; Yasuhiro Takagi; Yusuke Kitazume; Masanobu Kawakami

2006-01-01

340

Dynamic changes in circulating leukocytes during the induction of equine laminitis with black walnut extract.  

PubMed

Administration of black walnut heartwood extract (BWHE) via nasogastric tube induces acute laminitis in horses. However, the processes responsible for the development of laminitis, including laminitis induced with BWHE, remain unclear. The results of recent studies indicate that administration of BWHE initiates an inflammatory response in the laminar tissues and that this response may be due to extravasation of activated leukocytes from the circulation. This study examines the effects of BWHE administration on the dynamics of circulating neutrophils and monocytes, and the capacity of blood leukocytes to produce radical oxygen species (ROS) over the time period from administration of BWHE to the development of lameness consistent with Obel grade I laminitis. Individual horses, free of pre-existing musculoskeletal disease, were administered either 6l of BWHE or an equal volume of water at time 0 (T=0). Blood samples were collected prior to dosing and at 1, 2, 3, 4, 6, 8, 10 and 12h after dosing, or until the onset of Obel grade I laminitis. For each sample, total leukocyte counts were determined followed by collection of buffy coats and removal of erythrocytes by hypotonic lysis. Leukocytes were either fixed for flow cytometric assessment of differential counts or maintained in culture to measure endogenous and phorbol ester-induced production of ROS. At each sample time, the number of cells recovered and the flow cytometric differential counts were compared with corresponding total leukocyte counts determined by the Clinical Pathology laboratory. Horses administered BWHE had a significant reduction in circulating leukocytes at 3-4 h relative to values for horses administered the same volume of water. Horses that developed Obel grade I laminitis had a significant reduction in circulating leukocytes when compared to values for horses administered BWHE that did not become lame. Flow cytometric analysis revealed a consistent decrease in the total number of monocytes obtained from horses that developed laminitis. In these same horses, the endogenous level of ROS production was significantly higher at T=0 than for horses that did not become lame. Furthermore, production of ROS by leukocytes from horses that developed laminitis increased significantly and coincided with the decrease in circulating leukocytes. Collectively, these findings support a role for systemic activation of leukocytes and induction of inflammation by BWHE as a factor in the early pathogenesis of acute laminitis. Because laminitis often develops as a sequel to diseases characterized by systemic inflammatory events, activation and emigration of neutrophils and monocytes may be important factors in the early pathogenesis of laminitis in clinical cases. PMID:16290066

Hurley, David J; Parks, Robert J; Reber, Adrian J; Donovan, Douglas C; Okinaga, Tatsuyuki; Vandenplas, Michel L; Peroni, John F; Moore, James N

2006-04-15

341

Optimizing Viable Leukocyte Sampling from the Female Genital Tract for Clinical Trials: An International Multi-Site Study  

PubMed Central

Background Functional analysis of mononuclear leukocytes in the female genital mucosa is essential for understanding the immunologic effects of HIV vaccines and microbicides at the site of HIV exposure. However, the best female genital tract sampling technique is unclear. Methods and Findings We enrolled women from four sites in Africa and the US to compare three genital leukocyte sampling methods: cervicovaginal lavages (CVL), endocervical cytobrushes, and ectocervical biopsies. Absolute yields of mononuclear leukocyte subpopulations were determined by flow cytometric bead-based cell counting. Of the non-invasive sampling types, two combined sequential cytobrushes yielded significantly more viable mononuclear leukocytes than a CVL (p<0.0001). In a subsequent comparison, two cytobrushes yielded as many leukocytes (?10,000) as one biopsy, with macrophages/monocytes being more prominent in cytobrushes and T lymphocytes in biopsies. Sample yields were consistent between sites. In a subgroup analysis, we observed significant reproducibility between replicate same-day biopsies (r?=?0.89, p?=?0.0123). Visible red blood cells in cytobrushes increased leukocyte yields more than three-fold (p?=?0.0078), but did not change their subpopulation profile, indicating that these leukocytes were still largely derived from the mucosa and not peripheral blood. We also confirmed that many CD4+ T cells in the female genital tract express the ?4?7 integrin, an HIV envelope-binding mucosal homing receptor. Conclusions CVL sampling recovered the lowest number of viable mononuclear leukocytes. Two cervical cytobrushes yielded comparable total numbers of viable leukocytes to one biopsy, but cytobrushes and biopsies were biased toward macrophages and T lymphocytes, respectively. Our study also established the feasibility of obtaining consistent flow cytometric analyses of isolated genital cells from four study sites in the US and Africa. These data represent an important step towards implementing mucosal cell sampling in international clinical trials of HIV prevention. PMID:24454917

De Rosa, Stephen C.; Martinson, Jeffrey A.; Plants, Jill; Brady, Kirsten E.; Gumbi, Pamela P.; Adams, Devin J.; Vojtech, Lucia; Galloway, Christine G.; Fialkow, Michael; Lentz, Gretchen; Gao, Dayong; Shu, Zhiquan; Nyanga, Billy; Izulla, Preston; Kimani, Joshua; Kimwaki, Steve; Bere, Alfred; Moodie, Zoe; Landay, Alan L.; Passmore, Jo-Ann S.; Kaul, Rupert; Novak, Richard M.; McElrath, M. Juliana; Hladik, Florian

2014-01-01

342

Sour cherry seed kernel extract increases heme oxygenase-1 expression and decreases representation of CD3+ TNF-?+ and CD3+IL-8+ subpopulations in peripheral blood leukocyte cultures from type 2 diabetes patients.  

PubMed

The present study evaluates a hypothesis that sour cherry (Prunus cerasus) seed extracts (SCE) modulate CD3+ T lymphocyte activity in ways predictive of potential for uses of SCE in management of inflammatory diseases. Peripheral blood mononuclear cells (PBMC) from 12 type 2 diabetes (T2DM) patients and eight healthy control subjects were cultured 24 h with 100 ng/ml lipopolysaccharide (LPS) to increase inflammatory signaling and co-incubated with 0.5-100 µg/ml SCE. Cultures were evaluated by two-color flow cytometry for percent representation of CD3+ IL8+ and CD3+TNF-? cells which express interleukin-8 (IL-8), and tumor necrosis factor-?, (TNF-?+) respectively, and by enzyme-linked immunoassay for lymphocyte-associated heme oxygenase-1 (HO-1, known to be induced by SCE). SCE dosage ranges of 0.5-100 µg/ml in cell cultures significantly suppressed LPS-increased CD3+TNF-?+ and CD3+IL8+ representation from all participants (p?

Mahmoud, Fadia F; Al-Awadhi, Rana; Haines, David D; Dashti, Ali; Dashti, Hussain; Al-Ozairi, Ebaa; Bak, Istvan; Tosaki, Arpad

2013-05-01

343

Cardiopulmonary Bypass during Cardiac Surgery Modulates Systemic Inflammation by Affecting Different Steps of the Leukocyte Recruitment Cascade  

PubMed Central

Background It is known that the use of a cardiopulmonary bypass (CPB) during cardiac surgery leads to leukocyte activation and may, among other causes, induce organ dysfunction due to increased leukocyte recruitment into different organs. Leukocyte extravasation occurs in a cascade-like fashion, including capturing, rolling, adhesion, and transmigration. However, the molecular mechanisms of increased leukocyte recruitment caused by CPB are not known. This clinical study was undertaken in order to investigate which steps of the leukocyte recruitment cascade are affected by the systemic inflammation during CPB. Methods We investigated the effects of CPB on the different steps of the leukocyte recruitment cascade in whole blood from healthy volunteers (n?=?9) and patients undergoing cardiac surgery with the use of cardiopulmonary bypass (n?=?7) or in off-pump coronary artery bypass-technique (OPCAB, n?=?9) by using flow chamber experiments, transmigration assays, and biochemical analysis. Results CPB abrogated selectin-induced slow leukocyte rolling on E-selectin/ICAM-1 and P-selectin/ICAM-1. In contrast, chemokine-induced arrest and transmigration was significantly increased by CPB. Mechanistically, the abolishment of slow leukocyte rolling was due to disturbances in intracellular signaling with reduced phosphorylation of phospholipase C (PLC) ?2, Akt, and p38 MAP kinase. Furthermore, CPB induced an elevated transmigration which was caused by upregulation of Mac-1 on neutrophils. Conclusion These data suggest that CPB abrogates selectin-mediated slow leukocyte rolling by disturbing intracellular signaling, but that the clinically observed increased leukocyte recruitment caused by CPB is due to increased chemokine-induced arrest and transmigration. A better understanding of the underlying molecular mechanisms causing systemic inflammation after CPB may aid in the development of new therapeutic approaches. PMID:23029213

Rossaint, Jan; Berger, Christian; Van Aken, Hugo; Scheld, Hans H.; Zahn, Peter K.; Rukosujew, Andreas; Zarbock, Alexander

2012-01-01

344

Cypermethrin alters the status of oxidative stress in the peripheral blood: relevance to Parkinsonism.  

PubMed

Parkinson's disease (PD) is a motor scarcity disorder characterized by the striatal dopamine deficiency owing to the selective degeneration of the nigrostriatal dopaminergic neurons. While oxidative stress is implicated in PD, prolonged exposure to moderate dose of cypermethrin induces Parkinsonism. The study aimed to investigate the status of oxidative stress indicators and antioxidant defence system of the polymorphonuclear leukocytes (PMNs), platelets and plasma to delineate the effect of Parkinsonian dose of cypermethrin in the peripheral blood of rats and its subsequent relevance to Parkinsonism. Nitrite content, lipid peroxidation (LPO) and activity of superoxide dismutase (SOD), catalase, glutathione reductase (GR) and glutathione-S-transferase (GST) were measured in the PMNs, platelets and plasma of control and cypermethrin-treated rats in the presence or absence of a microglial activation inhibitor, minocycline or a dopamine precursor containing the peripheral 3,4-dihydroxyphenylalanine decarboxylase inhibitor, named syndopa, employing the standard procedures. The striatal dopamine was measured to assess the degree of neurodegeneration/neuroprotection. Cypermethrin increased nitrite and LPO in the plasma, platelets and PMNs while it reduced the striatal dopamine content. Catalase and GST activity were increased in the PMNs and platelets; however, it was reduced in the plasma. Conversely, SOD and GR activities were reduced in the PMNs and platelets but increased in the plasma. Minocycline or syndopa reduced the cypermethrin-mediated changes towards normalcy. The results demonstrate that cypermethrin alters the status of oxidative stress indicators and impairs antioxidant defence system of the peripheral blood, which could be effectively salvaged by minocycline or syndopa. The results could be of value for predicting the nigrostriatal toxicity relevant to Parkinsonism. PMID:25270427

Tripathi, Pratibha; Singh, Ashish; Agrawal, Sonal; Prakash, Om; Singh, Mahendra Pratap

2014-12-01

345

The multiple faces of leukocyte interstitial migration  

PubMed Central

Spatiotemporal control of leukocyte dynamics within tissues is critical for successful innate and adaptive immune responses. Homeostatic trafficking and coordinated infiltration into and within sites of inflammation and infection rely on signaling in response to extracellular cues that in turn controls a variety of intracellular protein networks regulating leukocyte motility, migration, chemotaxis, positioning, and cell–cell interaction. In contrast to mesenchymal cells, leukocytes migrate in an amoeboid fashion by rapid cycles of actin polymerization and actomyosin contraction, and their migration in tissues is generally referred to as low adhesive and nonproteolytic. The interplay of actin network expansion, contraction, and adhesion shapes the exact mode of amoeboid migration, and in this review, we explore how leukocyte subsets potentially harness the same basic biomechanical mechanisms in a cell-type-specific manner. Most of our detailed understanding of these processes derives from in vitro migration studies in three-dimensional gels and confined spaces that mimic geometrical aspects of physiological tissues. We summarize these in vitro results and then critically compare them to data from intravital imaging of leukocyte interstitial migration in mouse tissues. We outline the technical challenges of obtaining conclusive mechanistic results from intravital studies, discuss leukocyte migration strategies in vivo, and present examples of mode switching during physiological interstitial migration. These findings are also placed in the context of leukocyte migration defects in primary immunodeficiencies. This overview of both in vitro and in vivo studies highlights recent progress in understanding the molecular and biophysical mechanisms that shape robust leukocyte migration responses in physiologically complex and heterogeneous environments. PMID:24573488

Lämmermann, Tim; Germain, Ronald N.

2014-01-01

346

Morphine inhibits migration of tumor-infiltrating leukocytes and suppresses angiogenesis associated with tumor growth in mice.  

PubMed

Tumor cells secrete factors that stimulate the migration of peripheral blood leukocytes and enhance tumor progression by affecting angiogenesis. In these studies, we investigated the effect of morphine, a known immunosuppressant, on leukocyte migration and recruitment to conditioned media derived from long-term cultures of mouse Lewis lung carcinoma cells. Our results indicate that morphine treatment reduced the migration and recruitment of tumor-infiltrating leukocytes into Matrigel plugs and polyvinyl alcohol sponges containing conditioned media derived from long-term cultures of mouse Lewis lung carcinoma cells when compared with placebo. A reciprocal increase in peripheral blood leukocytes was observed at the time of plug or sponge removal in morphine-treated mice. Decreased angiogenesis was observed in conditioned media derived from long-term cultures of mouse Lewis lung carcinoma cells Matrigel plugs taken from morphine-treated wild-type mice when compared with placebo but was abolished in morphine-treated ?-opioid receptor knockout mice. In addition, in vitro studies using trans-well and electric cell substrate impedance sensing system studies reveal for the first time morphine's inhibitory effects on leukocyte migration and their ability to transmigrate across an activated endothelial monolayer. Taken together, these studies indicate that morphine treatment can potentially decrease leukocyte transendothelial migration and reduce angiogenesis associated with tumor growth. The use of morphine for cancer pain management may be beneficial through its effects on angiogenesis. PMID:24495739

Koodie, Lisa; Yuan, Hongyan; Pumper, Jeffery A; Yu, Haidong; Charboneau, Richard; Ramkrishnan, Sundaram; Roy, Sabita

2014-04-01

347

Leukocyte analysis using monoclonal antibodies in human glomerulonephritis  

Microsoft Academic Search

Leukocyte analysis using monoclonal antibodies in human glomerulonephritis. The leukocyte subpopulations were analyzed within both the glomeruli and the interstitium in renal biopsies from 145 patients with various forms of glomerulonephritis. Cells were identified by monoclonal antibodies to leukocyte cell–surface antigens and immunoper-oxidase labelling. Leukocytes, as defined by a monoclonal antibody to the leukocyte common antigen (PHM1), were present in

David H Hooke; David C Gee; Robert C Atkins

1987-01-01

348

Exposure to sodium fluoride produces signs of apoptosis in rat leukocytes.  

PubMed

Fluoride is naturally present in the earth's crust and can be found in rocks, coal, and clay; thus, it can be found in small quantities in water, air, plants, and animals. Therefore, humans are exposed to fluoride through food, drinking water, and in the air they breathe. Flouride is essential to maintain bone strength and to protect against dental decay, but if it is absorbed too frequently, it can cause tooth decay, osteoporosis, and damage to kidneys, bones, nerves, and muscles. Therefore, the present work was aimed at determining the effect of intake of sodium fluoride (NaF) as an apoptosis inducer in leukocytes of rats treated for eight weeks with 1 or 50 parts per million (ppm) NaF. Expression of p53, bcl-2, and caspade-3 were used as apoptotic and general metabolism indicators of leukocyte-like indicators of the (INT) oxidation system. Male rats were exposed to NaF (1 and 500 ppm) for eight weeks, and then sacrificed weekly to obtain blood samples. Expression of p53, bcl-2, and caspase-3 were determined in leukocytes by Western blot, and general metabolism of leukocytes was analyzed with a commercial kit. We found changes in the expression of the proteins described, especially when the animals received 50 ppm of NaF. These results indicate that NaF intoxication can be an apoptosis inducer in rat leukocytes treated with the compound for eight weeks. PMID:20957113

Gutiérrez-Salinas, José; Morales-González, José A; Madrigal-Santillán, Eduardo; Esquivel-Soto, Jaime; Esquivel-Chirino, César; González-Rubio, Manuel García-Luna Y; Suástegui-Domínguez, Sigrit; Valadez-Vega, Carmen

2010-01-01

349

Exposure to Sodium Fluoride Produces Signs of Apoptosis in Rat Leukocytes  

PubMed Central

Fluoride is naturally present in the earth’s crust and can be found in rocks, coal, and clay; thus, it can be found in small quantities in water, air, plants, and animals. Therefore, humans are exposed to fluoride through food, drinking water, and in the air they breathe. Flouride is essential to maintain bone strength and to protect against dental decay, but if it is absorbed too frequently, it can cause tooth decay, osteoporosis, and damage to kidneys, bones, nerves, and muscles. Therefore, the present work was aimed at determining the effect of intake of sodium fluoride (NaF) as an apoptosis inducer in leukocytes of rats treated for eight weeks with 1 or 50 parts per million (ppm) NaF. Expression of p53, bcl-2, and caspade-3 were used as apoptotic and general metabolism indicators of leukocyte-like indicators of the (INT) oxidation system. Male rats were exposed to NaF (1 and 500 ppm) for eight weeks, and then sacrificed weekly to obtain blood samples. Expression of p53, bcl-2, and caspase-3 were determined in leukocytes by Western blot, and general metabolism of leukocytes was analyzed with a commercial kit. We found changes in the expression of the proteins described, especially when the animals received 50 ppm of NaF. These results indicate that NaF intoxication can be an apoptosis inducer in rat leukocytes treated with the compound for eight weeks. PMID:20957113

Gutiérrez-Salinas, José; Morales-González, José A.; Madrigal-Santillán, Eduardo; Esquivel-Soto, Jaime; Esquivel-Chirino, César; González-Rubio, Manuel García-Luna y; Suástegui-Domínguez, Sigrit; Valadez-Vega, Carmen

2010-01-01

350

L-selectin-deficient mice have impaired leukocyte recruitment into inflammatory sites  

PubMed Central

L-selectin, a cell surface adhesion molecule that is expressed by most leukocytes, mediates leukocyte rolling along vascular endothelium at sites of inflammation. The contribution of L-selectin to leukocyte migration in models of chronic inflammation was assessed by using mice that lack cell surface L-selectin expression. Significant inhibition of neutrophil (56-62%), lymphocyte (70-75%), and monocyte (72-78%) migration into an inflamed peritoneum was observed 24 and 48 h after administration of thioglycollate, an inflammatory stimulus. L-selectin- deficient mice were also significantly impaired in delayed-type hypersensitivity reactions. Footpad swelling in response to sheep red blood cell challenge was reduced 75% in L-selectin-deficient mice compared with wild-type mice. Ear swelling in a model of contact hypersensitivity induced by oxazolone challenge was also reduced by 69% compared to wild-type mice. Consistent with L-selectin-mediating leukocyte migration into diverse vascular beds during inflammation, L- selectin-deficient mice were significantly resistant to death resulting from lipopolysaccharide (LPS)-induced toxic shock. LPS administration resulted in a 90% mortality rate in control mice after 24 h, while there was a 90% survival rate in L-selectin-deficient mice. These results demonstrate that L-selectin plays a prominent role in leukocyte homing to nonlymphoid tissues during inflammation and that blocking this process can be beneficial during pathological inflammatory responses. PMID:7539045

1995-01-01

351

A novel mutation in leukocyte adhesion deficiency type II/CDGIIc.  

PubMed

Leukocyte adhesion deficiencies (LAD) are autosomal recessive immunodeficiency syndromes characterized by severe and recurrent bacterial infections, impaired wound healing and leukocytosis. Block in different steps in the leukocyte adhesion cascade causes different types of leukocyte adhesion deficiencies, LAD type I, II and III. In LAD type II, the rolling phase of the leukocyte adhesion cascade is affected due to mutations in the specific fucose transporter GFTP (GDP fucose transporter), causing defect in the biosynthesis of selectin ligands on leukocytes. Thus this syndrome is also called congenital disorder of glycosylation IIc (CGDIIc). LAD II/CGDIIc is very rare and has been diagnosed in nine children to date. Fever, leukocytosis, typical dysmorphic features, growth, psychomotor retardation and the Bombay blood group, are characteristic findings in patients. Here, we describe two Turkish siblings with a novel mutation in GFTP. They both have the characteristic features of the syndrome. The older sibling died of severe bacterial pneumonia at the age of 3 years. The younger sibling, diagnosed at the age of 3 months, responded to high dose oral fucose supplementation. Secundum atrial septal defect which was not described in previously reported patients, but present in both of our patients, may primarily related to the defect in fucosylation. PMID:25239688

Cagdas, Deniz; Yilmaz, Mustafa; Kandemir, Nurgün; Tezcan, Ilhan; Etzioni, Amos; Sanal, Özden

2014-11-01

352

A decrease in effective diameter of rat mesenteric venules due to leukocyte margination after a bolus injection of pentoxifylline--digital image analysis of an intravital microscopic observation.  

PubMed

The ability of leukocytes to adhere to endothelial cells (EC) and then to migrate out of the blood stream into tissues enable them to perform their surveillance functions. Adhesion of leukocytes to EC is, however, only possible if the cells have marginated as a result of rheological interaction with other blood cells in flow. Using Pentoxifylline (PTX), a rheologically active drug, to manipulate this interaction, we have imaged and quantified this margination phenomenon in vivo. A system has been developing to perform this imaging via an intravital microscope connected to an image processing system. Albino rats were anesthetized and cannulated for intravenous bolus injection (0.5 ml) of PTX (1.25 mg/ml) through the femoral vein. A longitudinal incision exposed the mesentery, part of which was observed under microscope to visualize microcirculation. The image of interest was then stored on computer hard drive. Individual leukocyte velocities were determined before and after PTX infusion. The leukocytes, marginating and sticking after PTX infusion either remained attached, constituting the peripheral marginating leukocyte pool in the postcapillary venules, or detached with different step velocities. The reduction in effective venular diameters as a result of leukocyte margination was estimated to be 32-44%. These results demonstrate the biological importance of hemodynamic displacement leading to docking, adhesion, rolling and migration processes of leukocytes in blood. PMID:15121449

Hussain, M A; Merchant, S N; Mombasawala, L S; Puniyani, R R

2004-05-01

353

Induced expression and functional effects of aquaporin-1 in human leukocytes in sepsis  

PubMed Central

Introduction Gene expression profiling was performed via DNA microarrays in leukocytes from critically ill trauma patients nonseptic upon admission to the ICU, who subsequently developed either sepsis (n = 2) or severe sepsis and acute respiratory distress syndrome (n = 3). By comparing our results with published expression profiling studies in animal models of sepsis and lung injury, we found aquaporin-1 to be differentially expressed across all studies. Our aim was to determine how the water channel aquaporin-1 is involved in regulating the immune response in critically ill patients during infection acquired in the ICU. Methods Following the results of the initial genetic screening study, we prospectively followed aquaporin-1 leukocyte expression patterns in patients with ICU-acquired sepsis who subsequently developed septic shock (n = 16) versus critically ill patients who were discharged without developing sepsis (n = 13). We additionally determined aquaporin-1 expression upon lipopolysaccharide (LPS) exposure and explored functional effects of aquaporin-1 induction in polymorphonuclear granulocytes (PMNs). Results Leukocyte aquaporin-1 expression was induced at the onset of sepsis (median 1.71-fold increase; interquartile range: 0.99 to 2.42, P = 0.012 from baseline) and was further increased upon septic shock (median 3.00-fold increase; interquartile range: 1.20 to 5.40, P = 0.023 from sepsis, Wilcoxon signed-rank test); no difference was observed between baseline and discharge in patients who did not develop sepsis. Stimulation of PMNs by LPS led to increased expression of aquaporin-1 in vitro, which could be abrogated by the NF-?B inhibitor EF-24. PMN hypotonic challenge resulted in a transient increase of the relative cell volume, which returned to baseline after 600 seconds, while incubation in the presence of LPS resulted in persistently increased cell volume. The latter could be abolished by blocking aquaporin-1 with mercury and restored by incubation in ?-mercaptoethanol, which abrogated the action of mercury inhibition. Conclusions Aquaporin-1 is induced in leukocytes of patients with ICU-acquired sepsis and exhibits higher expression in septic shock. This phenomenon may be due to LPS-triggered NF-?B activation that can also lead to alterations in plasma membrane permeability. PMID:24028651

2013-01-01

354

Current good manufacturing practices for blood and blood components: notification of consignees receiving blood and blood components at increased risk for transmitting HIV infection--FDA. Final rule.  

PubMed

The Food and Drug Administration (FDA) is amending the biologics regulations to require that blood establishments (including plasma establishments) prepare and follow written procedures for appropriate action when it is determined that Whole Blood, blood components (including recovered plasma), Source Plasma and Source Leukocytes at increased risk for transmitting human immunodeficiency virus (HIV) infection have been collected. This final rule requires that when a donor who previously donated blood is tested on a later donation in accordance with the regulations and tests repeatedly reactive for antibody to HIV, the blood establishment shall perform more specific testing using a licensed test, if available, and notify consignees who received Whole Blood, blood components, Source Plasma or Source Leukocytes from prior collections so that appropriate action is taken. Blood establishments and consignees are required to quarantine previously collected Whole Blood, blood components, Source Plasma and Source Leukocytes from such donors, and if appropriate, notify transfusion recipients. The Health Care Financing Administration (HCFA) is also issuing a final rule, published elsewhere in this Federal Register, which requires all transfusion services subject to HCFA's conditions of Medicare participation for hospitals to notify transfusion recipients who have received Whole Blood or blood components from a donor whose subsequent donation test results are positive for antibody to HIV (hereinafter referred to as HCFA's final rule). FDA is requiring transfusion services that do not participate in Medicare and are, therefore, not subject to HCFA's final rule, to take steps to notify transfusion recipients. FDA is taking this action to help ensure the continued safety of the blood supply, and to help ensure that information is provided to consignees of Whole Blood, blood components, Source Plasma and Source Leukocytes and to recipients of Whole Blood and blood components from a donor whose subsequent donation tests positive for antibody to HIV. PMID:10160337

1996-09-01

355

Indium-111-labeled leukocyte localization in hematomas: a pitfall in abscess detection  

SciTech Connect

Indium-111-labeled white-blood-cell scanning is a useful modality in abscess detection and has replaced gallium scanning in many institutions. Sensitivities of 72% to 90% and specificities of 90% to 100% have been reported. In searching for abscesses seven cases of indium-111-labeled leukocyte uptake were encountered in collections subsequently proved to be noninfected hematomas. Abundant red blood cells with few or no white blood cells, no bacteria, and a benign clinical course identified these noninfected hematomas. Five of the patients were being treated with hemodialysis and three were recent allograft recipients. The results indicate some limitation and nonspecificity in indium-111 scanning, despite its many benefits.

Wing, V.W.; vanSonnenberg, E.; Kipper, S.; Bieberstein, M.P.

1984-07-01

356

Viral replication and interferon production in fetal and adult ovine leukocytes and spleen cells.  

PubMed Central

Peripheral blood leukocyte and spleen cell cultures derived from adult sheep and from third-trimester (107 to 145 days of gestation) and second-trimester (70 to 98 days of gestation) fetal lambs were examined for their ability to support viral replication and to produce interferon. Bluetongue virus, Herpesvirus hominis type 2, and Chikungunya virus failed to replicate in either leukocyte or spleen cell cultures derived from adult ewes or in cultures from second- or third-trimester fetal lambs. Similarly, peripheral blood leukocytes from adult sheep or third-trimester fetal lambs did not support the replication of Semliki Forest virus, vesicular stomatitis virus, Newcastle disease virus, or vaccinia virus. No major differences were observed in the ability of fetal and adult leukocytes to produce interferon in response to viral infection. In contrast, mean interferon titers induced by bluetongue virus, H. hominis type 2, and Chikungunya virus in spleen cells from second-trimester fetuses were 4- to 10-fold greater than those induced in spleen cells from adult ewes. Variations in interferon levels induced on separate occasions with cells from the same donor age group were observed. The antiviral substance induced in both the fetal and adult cell cultures fulfilled the usual criteria for characterization as interferon. PMID:172452

Rinaldo, C R; Overall, J C; Glasgow, L A

1975-01-01

357

Administration of anesthetic and analgesic prevent the suppression of many leukocyte responses following surgical castration and physical dehorning.  

PubMed

The objectives of the current research were to determine the physiological effects and responses of many leukocytes following surgical castration and/(or) physical dehorning and the influence of anesthetics and analgesics in 3-month-old calves. Eighty 3-month-old Holstein bull calves were completely randomized to treatments in a 2 × 2 × 2 factorial arrangement with castration, dehorning, and anesthetic/analgesic as the main effects. Peripheral blood samples were collected just before (0) and 0.5, 1.5, 2.5, 4, 6, 24, and 72 h after the respective procedure(s) and analyzed for total leukocyte and differential counts, as well as plasma cortisol and haptoglobin concentrations. Blood from the 0, 0.5 and 24h collections were analyzed for many ex vivo leukocyte responses. Data were analyzed using a repeated measures analysis of variance with the fixed effects of treatment, time, and the interaction of treatment × time. Pre-planned contrasts were performed to determine the effect of (1) management procedure (castration and/(or) dehorning), (2) anesthetic/analgesic, and (3) were the management procedures additive. There were treatment × time interactions (P<0.05) on plasma cortisol and haptoglobin concentrations as well as for total leukocyte and neutrophil concentrations in blood. Castration and dehorning increased cortisol concentrations and the effect of the procedures was additive (P<0.02). Dehorning alone elicited a greater (P<0.05) cortisol response than castration alone. In contrast, the leukocytosis and neutrophilia was greater (P<0.01) among castrated calves. In addition, haptoglobin concentrations at 24h after castration were elevated (P<0.01) in calves that were castrated. Both castration and dehorning suppressed (P=0.04) many leukocyte responses including the secretion of tumor necrosis factor-? when whole blood cultures were stimulated with lipopolysaccharide, surface expression of L-selectin on peripheral blood neutrophils, and the oxidative burst intensity of peripheral blood neutrophils when co-cultured with an Escherichia coli. The effects of castration and dehorning on blood leukocyte counts or any of the leukocyte responses were not additive (P>0.23). Castration and dehorning effects of plasma haptoglobin concentrations tended (P=0.10) to be additive at 72 h after the procedure(s). Prior administration of local anesthetic and a systemic analgesic attenuated (P<0.001) the cortisol response and prevented (P=0.03) the observed leukocytosis, neutrophilia, and leukocyte suppression. These data suggest that calves should be castrated and dehorned on the same day rather than spreading them out across two days and calves should be administered pain relief prior to performing either procedure. PMID:23270586

Ballou, M A; Sutherland, M A; Brooks, T A; Hulbert, L E; Davis, B L; Cobb, C J

2013-02-15

358

Flow cytometric analysis of the effect of dithiothreitol on leukocyte surface markers.  

PubMed

Pretreatment with dithiothreitol (DTT) is necessary to dissolve mucus in samples of induced sputum prior to analysis. However, DTT may affect cell surface markers which are essential for lymphocyte subtyping. Therefore, the aim of this study was to evaluate the effect of DTT on an appropriate panel of surface markers. Peripheral blood leukocytes were used because these cells, in contrast to sputum cells, could be obtained without DTT treatment. Peripheral blood from healthy donors was incubated with either DTT according to standard sputum procedures or phosphate-buffered saline (PBS), washed and incubated with fluorochrome-labelled antibodies. After lysis of erythrocytes, analysis was performed using a calibrated flow cytometer. Leukocyte populations were identified by their light scattering properties. For analysis, fluorescence intensity was compared between DTT- and PBS-treated samples. After treatment with DTT, fluorescence intensity was significantly increased in CD16-positive granulocytes; it was reduced in CD2-positive lymphocytes, CD45-positive lymphocytes and CD14-positive monocytes (p < or = 0.001). These changes occurred in all samples. The fluorescence intensity of CD3-, CD4-, CD8-, CD19-, CD56- and histocompatibility leukocyte antigen DR-positive lymphocytes was not altered by DTT. However, there were statistically significant (p<0.001), although small, changes in the percentages of leukocytes. The present data demonstrate that, although dithiothreitol as used in sputum analysis affects some surface markers of peripheral blood leukocytes, comparability between samples concerning lymphocyte surface markers is preserved. Therefore, it is suggested that treatment of sputum samples with dithiothreitol does not invalidate the immunocytochemical analysis of lymphocytes. PMID:10968510

Loppow, D; Böttcher, M; Gercken, G; Magnussen, H; Jörres, R A

2000-08-01

359

Prednisolone inhibits phagocytosis by polymorphonuclear leucocytes via steroid receptor mediated events  

PubMed Central

Prednisolone, at concentrations between 2·78 × 10?6 M (1 ?g/ml) and 1·39 × 10?8 M (5 × 10?3 ?g/ml) exerts an inhibitory effect on the phagocytosis of latex particles by normal human polymorphonuclear leucocytes in vitro as assessed by electron microscopical analysis. This inhibition appears to be receptor-mediated, as it is dependent upon RNA and protein synthesis and is glucocorticoid specific. Images PMID:6830325

Jones, Carolyn J. P.; Morris, Karen J.; Jayson, Malcolm I. V.

1983-01-01

360

agr-Dependent Interactions of Staphylococcus aureus USA300 with Human Polymorphonuclear Neutrophils  

Microsoft Academic Search

The emergence of serious infections due to community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) has fueled interest in the contributions of specific staphylococcal virulence factors to clinical disease. To assess the contributions of agr-dependent factors to the fate of organisms in polymorphonuclear neutrophils (PMN), we examined the consequences for organism and host cells of feeding PMN with wild-type CA-MRSA (LAC) or CA-MRSA

Yun Yun Pang; Jamie Schwartz; Matthew Thoendel; Laynez W. Ackermann; Alexander R. Horswill; William M. Nauseef

2010-01-01

361

Physical Activity, Sedentary Behavior, and Leukocyte Telomere Length in Women  

PubMed Central

Leukocyte telomere length (LTL) is a potential indicator of cellular aging; however, its relation to physical activity and sedentary behavior is unclear. The authors examined cross-sectionally associations among activity, sedentary behavior, and LTL among 7,813 women aged 43–70 years in the Nurses’ Health Study. Participants self-reported activity by questionnaire in 1988 and 1992 and sedentary behavior in 1992. Telomere length in peripheral blood leukocytes, collected in 1989–1990, was measured by quantitative polymerase chain reaction. The least-squares mean telomere length (z-score) was calculated after adjustment for age and other potential confounders. For total activity, moderately or highly active women had a 0.07-standard deviation (SD) increase in LTL (2-sided Ptrend = 0.02) compared with those least active. Greater moderate- or vigorous-intensity activity was also associated with increased LTL (SD = 0.11 for 2–4 vs. <1 hour/week and 0.04 for ?7 vs. <1 hour/week; 2-sided Ptrend = 0.02). Specifically, calisthenics or aerobics was associated with increased LTL (SD = 0.10 for ?2.5 vs. 0 hours/week; 2-sided Ptrend = 0.04). Associations remained after adjustment for body mass index. Other specific activities and sitting were unassociated with LTL. Although associations were modest, these findings suggest that even moderate amounts of activity may be associated with longer telomeres, warranting further investigation in large prospective studies. PMID:22302075

Du, Mengmeng; Prescott, Jennifer; Kraft, Peter; Han, Jiali; Giovannucci, Edward; Hankinson, Susan E.; De Vivo, Immaculata

2012-01-01

362

Heterotropic modulation of selectin affinity by allosteric antibodies affects leukocyte rolling.  

PubMed

Selectins are a family of adhesion receptors designed for efficient leukocyte tethering to the endothelium under shear. As a key property to resist premature bond disruption, selectin adhesiveness is enhanced by tensile forces that promote the conversion of a bent into an extended conformation of the N-terminal lectin and epidermal growth factor-like domains. Conformation-specific Abs have been invaluable in deciphering the activation mechanism of integrins, but similar reagents are not available for selectins. In this study, we show that the anti-human L-selectin mAbs DREG-55 and LAM1-5 but not DREG-56, DREG-200, or LAM1-1 heterotropically modulate adhesion presumably by stabilizing the extended receptor conformation. Force-free affinity assays, flow chamber, and microkinetic studies reveal a ligand-specific modulation of L-selectin affinity by DREG-55 mAb, resulting in a dramatic decrease of rolling velocity under flow. Furthermore, secondary tethering of polymorphonuclear cells was blocked by DREG-200 but significantly boosted by DREG-55 mAb. The results emphasize the need for a new classification for selectin Abs and introduce the new concept of heterotropic modulation of receptor function. PMID:24431230

Riese, Sebastian B; Kuehne, Christian; Tedder, Thomas F; Hallmann, Rupert; Hohenester, Erhard; Buscher, Konrad

2014-02-15

363

In vivo degradation of gonococcal outer membrane proteins within human leukocyte phagolysosomes.  

PubMed

We previously showed in vitro hydrolysis of outer membrane proteins by lysosomal proteases and purified elastase. In this study we examined the in vivo relevance of the previous studies. Outer membranes were obtained from Neisseria gonorrhoeae type 3 (strain GC7) by LiCl2 extraction. Some preparations were labeled with 125I. Phagocytizable particles were prepared by coating latex beads with outer membranes, and polymorphonuclear leukocytes were allowed to phagocytize serum-opsonized particles. After homogenization of neutrophils, phagolysosomes were recovered by flotation through sucrose. Phagolysosomes were prepared for slab gel electrophoresis immediately or incubated further at 37 degrees C to allow continued degradation of outer membrane proteins. The principal protein (protein I) and minor proteins (proteins II) of outer membranes were hydrolyzed in whole neutrophils and in isolated phagolysosomes. Proteins II were more susceptible to hydrolysis than protein I. Hydrolytic products formed were nearly identical in vivo and in vitro. We also radiolabeled the surface-exposed proteins of live gonococci. Degradation of outer membrane proteins on the intact bacteria within neutrophil and monocyte phagolysosomes was shown. This indicates that our earlier in vitro model is relevant to in vivo hydrolysis of gonococcal outer membrane proteins. PMID:6417023

Eaton, L J; Rest, R F

1983-12-01

364

Modeling leukocyte-leukocyte non-contact interactions in a lymph node.  

PubMed

The interaction among leukocytes is at the basis of the innate and adaptive immune-response and it is largely ascribed to direct cell-cell contacts. However, the exchange of a number of chemical stimuli (chemokines) allows also non-contact interaction during the immunological response. We want here to evaluate the extent of the effect of the non-contact interactions on the observed leukocyte-leukocyte kinematics and their interaction duration. To this aim we adopt a simplified mean field description inspired by the Keller-Segel chemotaxis model, of which we report an analytical solution suited for slowly varying sources of chemokines. Since our focus is on the non-contact interactions, leukocyte-leukocyte contact interactions are simulated only by means of a space dependent friction coefficient of the cells. The analytical solution of the Keller-Segel model is then taken as the basis of numerical simulations of interactions between leukocytes and their duration. The mean field interaction force that we derive has a time-space separable form and depends on the chemotaxis sensitivity parameter as well as on the chemokines diffusion coefficient and their degradation rate. All these parameters affect the distribution of the interaction durations. We draw a successful qualitative comparison between simulated data and sets of experimental data for DC-NK cells interaction duration and other kinematic parameters. Remarkably, the predicted percentage of the leukocyte-leukocyte interactions falls in the experimental range and depends (~25% increase) upon the chemotactic parameter indicating a non-negligible direct effect of the non-contact interaction on the leukocyte interactions. PMID:24204669

Gritti, Nicola; Caccia, Michele; Sironi, Laura; Collini, Maddalena; D'Alfonso, Laura; Granucci, Francesca; Zanoni, Ivan; Chirico, Giuseppe

2013-01-01

365

Modeling Leukocyte-Leukocyte Non-Contact Interactions in a Lymph Node  

PubMed Central

The interaction among leukocytes is at the basis of the innate and adaptive immune-response and it is largely ascribed to direct cell-cell contacts. However, the exchange of a number of chemical stimuli (chemokines) allows also non-contact interaction during the immunological response. We want here to evaluate the extent of the effect of the non-contact interactions on the observed leukocyte-leukocyte kinematics and their interaction duration. To this aim we adopt a simplified mean field description inspired by the Keller-Segel chemotaxis model, of which we report an analytical solution suited for slowly varying sources of chemokines. Since our focus is on the non-contact interactions, leukocyte-leukocyte contact interactions are simulated only by means of a space dependent friction coefficient of the cells. The analytical solution of the Keller-Segel model is then taken as the basis of numerical simulations of interactions between leukocytes and their duration. The mean field interaction force that we derive has a time-space separable form and depends on the chemotaxis sensitivity parameter as well as on the chemokines diffusion coefficient and their degradation rate. All these parameters affect the distribution of the interaction durations. We draw a successful qualitative comparison between simulated data and sets of experimental data for DC-NK cells interaction duration and other kinematic parameters. Remarkably, the predicted percentage of the leukocyte-leukocyte interactions falls in the experimental range and depends (?25% increase) upon the chemotactic parameter indicating a non-negligible direct effect of the non-contact interaction on the leukocyte interactions. PMID:24204669

Gritti, Nicola; Caccia, Michele; Sironi, Laura; Collini, Maddalena; D'Alfonso, Laura; Granucci, Francesca; Zanoni, Ivan; Chirico, Giuseppe

2013-01-01

366

Triggering of leukocytes by phase contrast in imaging cytometry with scanning fluorescence microscope (SFM)  

NASA Astrophysics Data System (ADS)

Slide-based cytometry (SBC) leads to breakthrough in cytometry of cells in tissues, culture and suspension. Carl Zeiss Imaging Solutions' new automated SFM combines imaging with cytometry. A critical step in image analysis is selection of appropriate triggering signal to detect all objects. Without correct target cell definition analysis is hampered. DNA-staining is among the most common triggering signals. However, the majority of DNA-dyes yield massive spillover into other fluorescence channels limiting their application. By microscopy objects of >5?m diameter can be easily detected by phase-contrast signal (PCS) without any staining. Aim was to establish PCS - triggering for cell identification. Axio Imager.Z1 motorized SFM was used (high-resolution digital camera, AxioCam MRm; AxioVision software: automatic multi-channel scanning, analysis). Leukocytes were stained with FITC (CD4, CD8) and APC (CD3) labelled antibodies in combinations using whole blood method. Samples were scanned in three channels (PCS/FITC/APC). Exposition-times for PCS were set as low as possible; the detection efficiency was verified by fluorescence. CD45-stained leukocytes were counted and compared to the number of PCS detected events. Leukocyte subtyping was compared with other cytometers. In focus the PCS of cells showed ring-form that was not optimal for cell definition. Out of focus PCS allows more effective qualitative and quantitative cell analyses. PCS was an accurate triggering signal for leukocytes enabling cell counting and discrimination of leukocytes from platelets. Leukocyte subpopulation frequencies were comparable to those obtained by other cytometers. In conclusion PCS is a suitable trigger-signal not interfering with fluorescence detection.

Bocsi, József; Pierzchalski, Arkadiusz; Marecka, Monika; Malkusch, Wolf; Tárnok, Attila

2009-02-01

367

Initial Afferent Lymphatic Vessels Controlling Outbound Leukocyte Traffic from Skin to Lymph Nodes  

PubMed Central

Tissue drains fluid and macromolecules through lymphatic vessels (LVs), which are lined by a specialized endothelium that expresses peculiar differentiation proteins, not found in blood vessels (i.e., LYVE-1, Podoplanin, PROX-1, and VEGFR-3). Lymphatic capillaries are characteristically devoid of a continuous basal membrane and are anchored to the ECM by elastic fibers that act as pulling ropes which open the vessel to avoid edema if tissue volume increases, as it occurs upon inflammation. LVs are also crucial for the transit of T lymphocytes and antigen presenting cells from tissue to draining lymph nodes (LN). Importantly, cell traffic control across lymphatic endothelium is differently regulated under resting and inflammatory conditions. Under steady-state non-inflammatory conditions, leukocytes enter into the lymphatic capillaries through basal membrane gaps (portals). This entrance is integrin-independent and seems to be mainly guided by CCL21 chemokine gradients acting on leukocytes expressing CCR7. In contrast, inflammatory processes in lymphatic capillaries involve a plethora of cytokines, chemokines, leukocyte integrins, and other adhesion molecules. Importantly, under inflammation a role for integrins and their ligands becomes apparent and, as a consequence, the number of leukocytes entering the lymphatic capillaries multiplies several-fold. Enhancing transmigration of dendritic cells en route to LN is conceivably useful for vaccination and cancer immunotherapy, whereas interference with such key mechanisms may ameliorate autoimmunity or excessive inflammation. Recent findings illustrate how, transient cell-to-cell interactions between lymphatic endothelial cells and leukocytes contribute to shape the subsequent behavior of leukocytes and condition the LV for subsequent trans-migratory events. PMID:24368908

Teijeira, Alvaro; Rouzaut, Ana; Melero, Ignacio

2013-01-01

368

Endothelial gaps and adherent leukocytes in allergen-induced early- and late-phase plasma leakage in rat airways.  

PubMed

Exposure of sensitized individuals to antigen can induce allergic responses in the respiratory tract, manifested by early and late phases of vasodilatation, plasma leakage, leukocyte influx, and bronchoconstriction. Similar responses can occur in the skin, eye, and gastrointestinal tract. The early-phase response involves mast cell mediators and the late-phase response is leukocyte dependent, but the mechanism of leakage is not understood. We sought to identify the leaky blood vessels, to determine whether these vessels contained endothelial gaps, and to analyze the relationship of the gaps to adherent leukocytes, using biotinylated lectins or silver nitrate to stain the cells in situ and Monastral blue as a tracer to quantify plasma leakage. Most of the leakage occurred in postcapillary venules (< 40-microns diameter), whereas most of the leukocyte migration (predominantly neutrophils) occurred in collecting venules. Capillaries and arterioles did not leak. Endothelial gaps were found in the leaky venules, both by silver nitrate staining and by scanning electron microscopy, and 94% of the gaps were distinct from sites of leukocyte adhesion or migration. We conclude that endothelial gaps contribute to both early and late phases of plasma leakage induced by antigen, but most leakage occurs upstream to sites of leukocyte adhesion. PMID:9626051

Baluk, P; Bolton, P; Hirata, A; Thurston, G; McDonald, D M

1998-06-01

369

SIRPbeta1 is expressed as a disulfide-linked homodimer in leukocytes and positively regulates neutrophil transepithelial migration.  

PubMed

Signal regulatory proteins (SIRPs) comprise a family of cell surface signaling receptors differentially expressed in leukocytes and the central nervous system. Although the extracellular domains of SIRPs are highly similar, classical motifs in the cytoplasmic or transmembrane domains distinguish them as either activating (beta) or inhibitory (alpha) isoforms. We reported previously that human neutrophils (polymorphonuclear leukocytes (PMN)) express multiple SIRP isoforms and that SIRPalpha binding to its ligand CD47 regulates PMN transmigration. Here we further characterized the expression of PMN SIRPs, and we reported that the major SIRPalpha and SIRPbeta isoforms expressed in PMN include Bit/PTPNS-1 and SIRPbeta1, respectively. Furthermore, although SIRPalpha (Bit/PTPNS-1) is expressed as a monomer, we showed that SIRPbeta1 is expressed on the cell surface as a disulfide-linked homodimer with bond formation mediated by Cys-320 in the membrane-proximal Ig loop. Subcellular fractionation studies revealed a major pool of SIRPbeta1 within the plasma membrane fractions of PMN. In contrast, the majority of SIRPalpha (Bit/PTPNS-1) is present in fractions enriched in secondary granules and is translocated to the cell surface after chemoattractant (formylmethionylleucylphenylalanine) stimulation. Functional studies revealed that antibody-mediated ligation of SIRPbeta1 enhanced formylmethionylleucylphenylalanine-driven PMN transepithelial migration. Co-immunoprecipitation experiments to identify associated adaptor proteins revealed a 10-12-kDa protein associated with SIRPbeta1 that was tyrosine-phosphorylated after PMN stimulation and is not DAP10/12 or Fc receptor gamma chain. These results provide new insights into the structure and function of SIRPs in leukocytes and their potential role(s) in fine-tuning responses to inflammatory stimuli. PMID:16081415

Liu, Yuan; Soto, Ileana; Tong, Qiao; Chin, Alex; Bühring, Hans-Jörg; Wu, Tao; Zen, Ke; Parkos, Charles A

2005-10-28

370

3,4-di-deoxyglucosone-3-ene promotes leukocyte apoptosis  

Microsoft Academic Search

3,4-di-deoxyglucosone-3-ene promotes leukocyte apoptosis.BackgroundHeat-sterilized, single-chambered, glucose-containing peritoneal dialysis solutions promote neutrophil apoptosis and impair the peritoneal antibacterial response. It has been proposed that glucose degradation products may be responsible for this effect. However, the precise contribution of individual glucose degradation products had not been addressed.MethodsThe effect of individual glucose degradation products on apoptosis in cultured human neutrophils and peripheral blood

MARINA PENÉLOPE CATALAN; BEATRIZ SANTAMARÍA; ANA REYERO; ARTURO ORTIZ; JESÚS EGIDO; ALBERTO ORTIZ

2005-01-01

371

LINE1 Methylation Levels in Leukocyte DNA and Risk of Renal Cell Cancer  

Microsoft Academic Search

PurposeLeukocyte global DNA methylation levels are currently being considered as biomarkers of cancer susceptibility and have been associated with risk of several cancers. In this study, we aimed to examine the association between long interspersed nuclear elements (LINE-1) methylation levels, as a biomarker of global DNA methylation in blood cell DNA, and renal cell cancer risk.Experimental DesignLINE-1 methylation of bisulfite-converted

Linda M. Liao; Paul Brennan; Dana M. van Bemmel; David Zaridze; Vsevolod Matveev; Vladimir Janout; Hellena Kollarova; Vladimir Bencko; Marie Navratilova; Neonila Szeszenia-Dabrowska; Dana Mates; Nathaniel Rothman; Paolo Boffetta; Wong-Ho Chow; Lee E. Moore

2011-01-01

372

Altered chemokine receptor profile on circulating leukocytes in human heart failure  

Microsoft Academic Search

Chemokines and their receptors have been implicated in the pathogenesis of different forms of heart failure (HF). We examined\\u000a CC-and CXC-chemokine receptor expression in fresh peripheral blood leukocyte populations from 24 end-stage HF patients consisting\\u000a of coronary artery disease (CAD; n=6) and hypertrophic cardiomyopathy (HCM; n=7) or idiopathic dilated cardiomyopathy (IDCM; n=8) or valvular disease (VD; n=3) and compared the

Petros Athanassopoulos; Leonard M. B. Vaessen; Aggie H. M. M. Balk; Willem Weimar; Hari S. Sharma; Ad J. J. C. Bogers

2006-01-01

373

Human Monocytes Bind to Two Cytokine-Induced Adhesive Ligands on Cultured Human Endothelial Cells: Endothelial-Leukocyte Adhesion Molecule1 and Vascular Cell Adhesion Molecule1  

Microsoft Academic Search

Vascular cell adhesion molecule-1 (VCAM-1) and endothelial- leukocyte adhesion molecule-1 (ELAM-I) are adhesive pro- teins induced on endothelium by cytokines. We examined the contribution of these adhesive proteins to human peripheral blood monocyte adherence to endothelium using transfected Chinese hamster ovary (CHO) cells stably expressing these proteins and monoclonal antibodies (MoAbs) to ELAM-I, VCAM-1, or CD49d\\/CD29 (VLA-4). the leukocyte receptor

T. Carlos; N. Kovach; M. Rosa; E. Wayner; C. Benjamin; L. Osborn; R. Lobb; J. Harlan

1991-01-01

374

Boundary-precise segmentation of nucleus and plasma of leukocytes  

NASA Astrophysics Data System (ADS)

The exact segmentation of nucleus and plasma of a white blood cell (leukocyte) is the basis for the creation of an automatic, image based differential white blood cell count(WBC). In this contribution we present an approach for the according segmentation of leukocytes. For a valid classification of the different cell classes, a precise segmentation is essential. Especially concerning immature cells, which can be distinguished from their mature counterparts only by small differences in some features, a segmentation of nucleus and plasma has to be as precise as possible, to extract those differences. Also the problems with adjacent erythrocyte cells and the usage of a LED illumination are considered. The presented approach can be separated into several steps. After preprocessing by a Kuwahara-filter, the cell is localized by a simple thresholding operation, afterwards a fast-marching method for the localization of a rough cell boundary is defined. To retrieve the cell area a shortest-path-algorithm is applied next. The cell boundary found by the fast-marching approach is finally enhanced by a post-processing step. The concluding segmentation of the cell nucleus is done by a threshold operation. An evaluation of the presented method was done on a representative sample set of 80 images recorded with LED illumination and a 63-fold magnification dry objective. The automatically segmented cell images are compared to a manual segmentation of the same dataset using the Dice-coefficient as well as Hausdorff-distance. The results show that our approach is able to handle the different cell classes and that it improves the segmentation quality significantly.

Zerfaß, Thorsten; Rehn, Thomas; Wittenberg, Thomas

2008-03-01

375

Oxidative stress and reduced responsiveness of challenged circulating leukocytes following pulmonary instillation of metal-rich particulate matter in rats.  

PubMed

Welding fume is an exposure that consists of a mixture of metal-rich particulate matter with gases (ozone, carbon monoxide) and/or vapors (VOCs). Data suggests that welders are immune compromised. Given the inability of pulmonary leukocytes to properly respond to a secondary infection in animal models, the question arose whether the dysfunction persisted systemically. Our aim was to evaluate the circulating leukocyte population in terms of cellular activation, presence of oxidative stress, and functionality after a secondary challenge, following welding fume exposure. Rats were intratracheally instilled (ITI) with PBS or 2 mg of welding fume collected from a stainless steel weld. Rats were sacrificed 4 and 24 h post-exposure and whole blood was collected. Whole blood was used for cellular differential counts, RNA isolation with subsequent microarray and Ingenuity Pathway Analysis, and secondary stimulation with LPS utilizing TruCulture technology. In addition, mononuclear cells were isolated 24 h post-exposure to measure oxidative stress by flow cytometry and confocal microscopy. Welding fume exposure had rapid effects on the circulating leukocyte population as identified by relative mRNA expression changes. Instillation of welding fume reduced inflammatory protein production of circulating leukocytes when challenged with the secondary stimulus LPS. The effects were not related to transcription, but were observed in conjunction with oxidative stress. These findings support previous studies of an inadequate pulmonary immune response following a metal-rich exposure and extend those findings showing leukocyte dysfunction occurs systemically. PMID:25123171

Erdely, Aaron; Antonini, James M; Young, Shih-Houng; Kashon, Michael L; Gu, Ja K; Hulderman, Tracy; Salmen, Rebecca; Meighan, Terence; Roberts, Jenny R; Zeidler-Erdely, Patti C

2014-01-01

376

Human leukocyte antigens in tuberculosis and leprosy  

Microsoft Academic Search

Human mycobacterial infections are characterized by a spectrum of clinical and immunological manifestations. Specific human leukocyte antigen (HLA) factors are associated with the subtypes of leprosy that develop and the course of tuberculosis after infection. The identification of protective mycobacterial antigens presented by a broad variety of HLA molecules will have important implications for the design of vaccines.

Christian G Meyer; Jürgen May; Klaus Stark

1998-01-01

377

MICROWAVES, HYPERTHERMIA, AND HUMAN LEUKOCYTE FUNCTION  

EPA Science Inventory

The objective of this study is to determine whether exposure to microwaves (2450 MHz) affects the function of human leukocytes in the resting state and during antigenic or mitogenic challenge. This publication is a summary report of the construction and calibration of a waveguide...

378

Cultured human endothelial cells stimulated with cytokines or endotoxin produce an inhibitor of leukocyte adhesion.  

PubMed Central

Activation of cultured human endothelial cells (HEC) by inflammatory stimuli, such as interleukin 1 (IL-1), tumor necrosis factor (TNF), and bacterial endotoxin (lipopolysaccharide, LPS), increases their surface adhesiveness for blood leukocytes and related cell lines. We now report that activated HEC also generate a soluble leukocyte adhesion inhibitor (LAI), which accumulates in conditioned media from IL-1-, TNF-, or LPS-treated, but not sham-treated, HEC cultures. LAI significantly inhibits the adhesion of PMN and monocytes to activated, but not unactivated, HEC. In contrast, LAI has no effect on the adhesion of lymphocytes, the promyelocytic cell line HL-60 or the monocyte-like cell line U937 to HEC monolayers. LAI appears to act directly on the leukocyte, but does not inhibit either agonist-induced responses in PMN (membrane depolarization, changes in cytosolic calcium concentration, superoxide production) or PMN attachment to serum-coated plastic surfaces. Endothelial generation of LAI is blocked by actinomycin D but not by aspirin or indomethacin. Preliminary biochemical characterization indicates that LAI is a soluble, protein-containing molecule that is heat- and acid-stable. Fractionation by HPLC gel filtration yields a single peak of LAI activity (14,000 less than Mr greater than 24,000). Thus, in addition to proadhesive cell surface changes, the endothelium may also actively contribute to the regulation of endothelial-leukocyte interactions at sites of inflammation in vivo through the production of soluble adhesion inhibitors such as LAI. Images PMID:3049673

Wheeler, M E; Luscinskas, F W; Bevilacqua, M P; Gimbrone, M A

1988-01-01

379

ADAM9 is a novel product of polymorphonuclear neutrophils: regulation of expression and contributions to extracellular matrix protein degradation during acute lung injury.  

PubMed

A disintegrin and a metalloproteinase domain (ADAM) 9 is known to be expressed by monocytes and macrophages. In this study, we report that ADAM9 is also a product of human and murine polymorphonuclear neutrophils (PMNs). ADAM9 is not synthesized de novo by circulating PMNs. Rather, ADAM9 protein is stored in the gelatinase and specific granules and the secretory vesicles of human PMNs. Unstimulated PMNs express minimal quantities of surface ADAM9, but activation of PMNs with degranulating agonists rapidly (within 15 min) increases PMN surface ADAM9 levels. Human PMNs produce small quantities of soluble forms of ADAM9. Surprisingly, ADAM9 degrades several extracellular matrix (ECM) proteins, including fibronectin, entactin, laminin, and insoluble elastin, as potently as matrix metalloproteinase-9. However, ADAM9 does not degrade types I, III, or IV collagen or denatured collagens in vitro. To determine whether Adam9 regulates PMN recruitment or ECM protein turnover during inflammatory responses, we compared wild-type and Adam9(-/-) mice in bacterial LPS- and bleomycin-mediated acute lung injury (ALI). Adam9 lung levels increase 10-fold during LPS-mediated ALI in wild-type mice (due to increases in leukocyte-derived Adam9), but Adam9 does not regulate lung PMN (or macrophage) counts during ALI. Adam9 increases mortality, promotes lung injury, reduces lung compliance, and increases degradation of lung elastin during LPS- and/or bleomycin-mediated ALI. Adam9 does not regulate collagen accumulation in the bleomycin-treated lung. Thus, ADAM9 is expressed in an inducible fashion on PMN surfaces where it degrades some ECM proteins, and it promotes alveolar-capillary barrier injury during ALI in mice. PMID:25063875

Roychaudhuri, Robin; Hergrueter, Anja H; Polverino, Francesca; Laucho-Contreras, Maria E; Gupta, Kushagra; Borregaard, Niels; Owen, Caroline A

2014-09-01

380

Combined Effects of Gamma Radiation and High Dietary Iron on Peripheral Leukocyte Distribution and Function  

NASA Technical Reports Server (NTRS)

Both radiation and increased iron stores can independently increase oxidative damage, resulting in protein, lipid and DNA oxidation. Oxidative stress increases the risk of many health problems including cancer, cataracts, and heart disease. This study, a subset of a larger interdisciplinary investigation of the combined effect of iron overload on sensitivity to radiation injury, monitored immune parameters in the peripheral blood of rats subjected to gamma radiation, high dietary iron or both. Specific immune measures consisted of: (1) peripheral leukocyte distribution, (2) plasma cytokine levels and (3) cytokine production profiles following whole blood mitogenic stimulation

Crucian, Brian E.; Morgan, Jennifer L. L.; Quiriarte, Heather A.; Sams, Clarence F.; Smith, Scott M.; Zwart, Sara R.

2012-01-01

381

Comparison of four leukocyte differential methods with the National Committee for Clinical Laboratory Standards (NCCLS) reference method.  

PubMed

The authors compared four leukocyte differential counting methods with the National Committee for Clinical Laboratory Standards Reference Leukocyte Differential Method H20-T to determine the clinical sensitivity of the methods. The three-part differential performed by the Coulter Counter Model S-Plus IV and the Toa E-5000, when combined with instrument flags and defined laboratory checking limits for red blood cell and platelet values, are safe and efficacious screening methods for the presence of morphologic abnormalities. The Geometric Data Hematrak 590 proved comparable in clinical sensitivity to a random 100-cell eye-count differential. PMID:3812351

Pierre, R V; Payne, B A; Lee, W K; Hyma, B A; Melchert, L M; Scheidt, R M

1987-02-01

382

Inhibitory effects of plant secondary metabolites on cytotoxic activity of polymorphonuclear leucocytes.  

PubMed

The inhibitory effects of 151 natural products, representing most of the frequently occurring types, on the cytotoxicity to MM2 tumor cells of polymorphonuclear leucocytes (PMN) induced by TAK, a polysaccharide immunomodulator, were examined. Forty-two compounds inhibited the TAK-induced activation of PMN. Among them, some naturally occurring quinones and various alkaloids (nicotine, Cinchona alkaloids, isoquinoline alkaloids such as cepharanthine, and indole alkaloids such as ajmaline) exhibited potent inhibitory effects. Using the inhibition assay for monitoring, the extracts of Hydrangea Dulcis folium, Scopoliae rhizoma, Cinchona cortex, Magnoliae cortex, Stephania tuber, and Rauwolfia radix were analysed to characterize the active constituents. PMID:1529025

Kinoshita, K; Morikawa, K; Fujita, M; Natori, S

1992-04-01

383

Activation of polymorphonuclear leukocytes reduces their adhesion to P-selectin and causes redistribution of ligands for P-selectin on their surfaces.  

PubMed Central

In acute inflammatory responses, selectins mediate initial rolling of neutrophils (PMNs) along the endothelial surface. This is followed by tight adhesion that requires activation-dependent up-regulation of CD11/CD18 integrins on PMNs. For emigration to occur, the initial bonds that are established at the endothelial surface must be disengaged. We show that activation of PMNs results in their detachment from P-selectin, a glycoprotein expressed at the surface of inflamed endothelium that mediates initial tethering of PMNs. Loosening of the bond occurs when PMNs are activated by platelet-activating factor, which is coexpressed with P-selectin, or by other signaling molecules. The time course of reduced adhesion to P-selectin, when compared to up-regulation of CD11/CD18 integrins, suggests that "bond trading" may occur as activated PMNs transmigrate in vivo. Activation of PMNs did not alter binding of fluid-phase P-selectin, indicating that the ligand(s) for P-selectin is not shed or internalized. Using microspheres coated with P-selectin, we found that ligands for P-selectin were randomly distributed over the surfaces of rounded, unactivated PMNs. An antibody against P-selectin glycoprotein ligand-1 (PSGL-1) completely inhibited binding of P-selectin-coated beads suggesting that P-selectin glycoprotein ligand-1 is the critical binding site in this assay. In contrast to the dispersed pattern on unactivated PMNs, the ligands for P-selectin were localized on the uropods of activated, polarized cells. Pretreating PMNs with cytochalasin D before activation prevented the change in cell shape, the redistribution of binding sites for P-selectin-coated beads, and the decrease in cellular adhesiveness for P-selectin. These experimen