Quantitation of superoxide production in human polymorphonuclear leukocytes from normals and 3 types of chronic granulomatous disease

Infusion of Hypertonic Saline (7.5%) Does Not Change Neutrophil Oxidative Burst or Expression of Endothelial Adhesion Molecules After Abdominal Hysterectomy

BACKGROUND

Previous studies found hypertonicity to affect neutrophils in intact laboratory animals and in human blood cell cultures. We investigated whether infusion of hypertonic saline in a clinical relevant dose before hysterectomy affected peripheral blood neutrophils and their response to surgery.

METHODS

Fifteen women scheduled for open abdominal hysterectomy were randomized double-blindly to infusion of 4 mL/kg 7.5% NaCl, 4 mL/kg 0.9% NaCl, or 32 mL/kg 0.9% NaCl over 20 minutes. Blood was collected at baseline, after infusion, 1, 4, and 24 hours postoperatively for the determination of leukocyte and differential count, neutrophil membrane expression of endothelial adhesion molecules by flow cytometry, and O2- -generation by superoxide dismutase-inhibitable reduction of cytochrome C.

RESULTS

Surgery induced well-known changes in the number and distribution of white blood cells, reduced the expression of adhesion molecules, and halved the superoxide production unrelated to the tonicity or volume of the infused fluids.

CONCLUSION

Infusion of a clinically relevant dose of hypertonic saline has no detectable effect on the membrane expression of endothelial adhesion molecules or O2- -generation in circulating neutrophils after elective abdominal hysterectomy.

Omeprazole treatment diminishes intra- and extracellular neutrophil reactive oxygen production and bactericidal activity

OBJECTIVE

Neutrophils play a crucial role in host defense against infectious disease. The objective was to analyze the effect of omeprazole treatment on indexes of neutrophil function in healthy subjects.

DESIGN

Open.

SETTING

University hospital.

SUBJECTS

Ten healthy subjects.

INTERVENTION

Analysis of blood samples before and after omeprazole administration.

MEASUREMENTS AND MAIN RESULTS

Neutrophil Escherichia coli phagocytosis was assessed by microscopy and flow cytometry. Intracellular production of reactive oxygen intermediates was measured by flow cytometry. Extracellular reactive oxygen intermediate production was assessed with a cytochrome c reduction assay. Neutrophil bactericidal capacity and intracellular concentrations of Ca2+ were determined by fluorometry. Four hours after a single 40-mg dose of omeprazole, intra- and extracellular reactive oxygen intermediate production by neutrophils was significantly reduced compared with pretreatment values: -30% (24% to 42%) (median and range) and -22% (21% to 68%; p <.05 for both). The intracellular Ca2+ concentrations in resting neutrophils were significantly increased (+33%, 21% to 39%, compared with pretreatment concentrations, p <.001) and neutrophilic bactericidal activity was decreased (-30%, 19% to 47%, compared with pretreatment concentrations, p <.0001). Intracellular Ca2+ concentrations correlated with intracellular reactive oxygen intermediate production and neutrophilic bactericidal capacity (r =.730 and r =.618, p <.05 for both, respectively). In contrast, phagocytosis rates were not impaired by omeprazole.

CONCLUSIONS

Our results imply that omeprazole impairs production of reactive oxygen intermediates by neutrophils. Whether specific impairments of neutrophil host defenses occur in vivo remains uncertain. Reduced bactericidal activity is associated with an increase of intracellular Ca2+ concentrations in resting neutrophils.

Effects of omeprazole on neutrophil chemotaxis, super oxide production, degranulation, and translocation of cytochrome b-245

The effects of omeprazole on polymorphonuclear neutrophil (PMN) chemotaxis, superoxide generation, degranulation and translocation of cytochrome b-245 were investigated. Omeprazole (10(-6) - 5 x 10(-3) mol/l) reduced chemotaxis under agarose in a dose dependent manner, and the effect was irreversible. Superoxide anion generation was inhibited 50% at a concentration of 2.5 x 10(-5) mol/l and completely abolished at 5 x 10(-3) mol/l. Acid degraded omeprazole also inhibited O2- generation. Omeprazole did not scavenge O2- generated in a cell free xanthin-xanthine oxidase system. Degranulation by PMNs was inhibited only by omeprazole in concentrations above 10(-4) mol/l. Translocation of cytochrome b-245, essential for generation of O2-, was not affected by omeprazole. In conclusion, the anti-ulcer agent omeprazole in concentrations obtained during intravenous administration may inhibit the function of PMNs in vitro.

Cytochrome b positive X-linked chronic granulomatous disease: a normal cell surface expression of cytochrome b

The polymorphonuclear (PMN) cells from a patient with cytochrome b positive X-linked chronic granulomatous disease (Xb+ CGD) were studied using flow cytometry. Both the cell surface expression of monoclonal antibody defined cytochrome b and the superoxide production (intracellular 2',7'-Dichlorofluorescin Diacetate oxidation) were investigated at a single cell level. Flow cytometry clearly demonstrated the complete absence of superoxide production in the patient's PMN cells, the mosaicism in his mother's PMN cells and also indicated the normal cell surface expression of cytochrome b. The results obtained by Western blot analysis and reduced-minus-oxidized spectra confirmed the presence of functional and normal amounts of cytochrome b. We concluded that this is a case of Xb+ CGD with a normal cell surface expression of cytochrome b.

Effects of sulphasalazine and its metabolites on neutrophil chemotaxis, superoxide production, degranulation and translocation of cytochrome b-245

This study describes effects of sulphasalazine, 5-amino-salicylic acid (5-ASA) and sulphapyridine on polymorphonuclear neutrophils. Chemotaxis by polymorphonuclear neutrophils incubated with 5-ASA was reduced in a concentration dependent fashion (10(-5)-10(-4) M). Degranulation and release of lysozyme and beta-glucuronidase by activated polymorphonuclear neutrophils was inhibited by sulphasalazine but inhibited by sulphasalazine (IC50: 2 x 10(-4) M) and to a lesser extent by 5-ASA (IC50: 10(-3) M). Using a cell-free system sulphasalazine was found to be a strong scavenger and 5-ASA and sulphapyridine had only weak effects. Superoxide anion production requires translocation of a cytochrome b-245 and this translocation was reduced by sulphasalazine (P less than 0.01) but not by 5-ASA or sulphapyridine. In conclusion, the intact sulphasalazine molecule has an action of its own and marked differences exist between the action of sulphasalazine and 5-ASA, which may be important for the clinical activity.

Neutrophil beta-2 microglobulin: an inflammatory mediator

Beta-2 microglobulin (beta 2m) constitutes the light invariant chain of HLA class I antigen, and is a constituent of mobilizable compartments of neutrophils. Two forms of beta 2m exist: native beta 2m and proteolytically modified beta 2m (Des-Lys58-beta 2m), which shows alpha mobility in crossed radioimmuno-electrophoresis. The modification of native beta 2m can be executed by membrane-associated activity of mononuclear cells, and Des-Lys58-beta 2m augments the production of interleukin 2. In this study we present evidence that human neutrophils contain native beta 2m in specific granules, secretory vesicles, and plasma membrane. Beta 2m was released in the native form from neutrophils in response to stimulation with chemotactic stimuli and phorbol ester. The results of experiments designed to study the modification of native beta 2m by neutrophils indicated that neutrophils do not participate in the proteolysis of beta 2m. However, we demonstrated that native beta 2m following degranulation may be transformed to Des-Lys58-beta 2m by lymphocytes. We suggest that neutrophil beta 2m following exocytosis may be transformed to Des-Lys58-beta 2m, acting as an extracellular messenger between granulocytes and lymphocytes in the inflammatory focus.

A study on the role of protein kinase C and intracellular calcium in the activation of superoxide generation

Accumulating evidence indicates that protein kinase C plays an essential role in the activation of NADPH oxidase. In the present study, the correlation between superoxide generation, intracellular calcium, activation of purified protein kinase C and stabilized membrane-bound protein kinase C was studied. Phorbol 12-myristate 13-acetate (PMA) and 1-deacyl-2-acetyl-rac-glycerol (OAG) were found to induce equal activation of purified protein kinase C and translocation of protein kinase C to the membrane fraction, but differed significantly in their ability to induce superoxide generation. Intracellular calcium was varied using calcium ionophores and increasing the intracellular calcium concentration to more than 1 microM was found to induce increased superoxide generation in maximally OAG-stimulated cells; this contrasted to maximally PMA-stimulated leukocytes. Ionomycin and A23187 were both found to induce a translocation of protein kinase C to the membrane fraction. This translocation was highly dependent upon extracellular calcium. In contrast, PMA- and OAG-induced translocation of protein kinase C was not dependent upon extracellular calcium. In conclusion, our results indicate that although PMA, OAG and calcium ionophores seem to activate protein kinase C in human polymorphonuclear leukocytes these activators differ in their ability to induce superoxide generation.

Polymorphonuclear leucocyte dysfunction during short term metabolic changes from normo- to hyperglycemia in type 1 (insulin dependent) diabetic patients

Polymorphonuclear leucocyte (PMN) ingestion of particles coated with lipopolysaccharide (LPS) from Escherichia coli was compared to other PMN functions in seven patients with insulin dependent diabetes mellitus (IDDM) during short-term controlled metabolic changes from normo- to hyperglycemia without ketoacidosis. Factors known to interfere with PMN functions were excluded. PMN ingestion of particles coated with both LPS and bovine serum albumin became reduced from normo- to hyperglycemia. PMN motility was impaired in IDDM, but did not seem to be affected by short-term changes in metabolic control. PMN metabolism did not change from normo-to hyperglycemia. Particle-uptake by diabetic PMN is impaired after short term hyperglycemia in the range normally occurring in diabetics in every-day life.

Free radicals, immunoglobulins and complement as mediators of inflammation

There is evidence for both oxygen-centred free radicals and products of complement activation acting as mediators of inflammation. Evidence for the generation and reaction of free radicals at sites of inflammation can only be indirect and circumstantial due to their very transient nature. Evidence for complement activation in several inflammatory conditions, including rheumatoid arthritis is strong. These mediator classes individually possess a range of potential proinflammatory activities. Their effects may be linked through the formation of immune complexes and the activation of polymorphonuclear leukocytes. Their actions will also be linked with and modulated by the activities of other mediators mentioned only briefly in this chapter. The relative importance of the different mediators in any particular inflammatory condition is difficult to ascertain. The importance of free radicals and complement will be better understood when drugs specifically and unequivocally aimed at their control are identified. This potential for therapeutic advances in the treatment of inflammatory disorders has yet to be realized.

Ca2+ and phorbol ester activation of protein kinase C at intracellular Ca2+ concentrations and the effect of TMB-8

A calcium-activated, phospholipid-dependent protein kinase (protein kinase C) was purified to near homogeneity from human polymorphonuclear leukocytes and shown to be identical to bovine protein kinase C. The Ca2+ activation of the enzyme was studied and the Ca2+ concentrations required to activate the enzyme were compared to free cytosolic Ca2+ concentrations in resting and activated polymorphonuclear leukocytes. The free calcium concentrations in the cytosol and in the enzyme assay mixture were determined using the calcium indicator quin 2. The enzyme activity was almost totally dependent upon phosphatidylserine and could be strongly activated by Ca2+ concentrations in the micromolar range, but was not activated by phosphatidylserine at Ca2+ concentrations corresponding to the intracellular free Ca2+ concentration under resting conditions. However, at similar Ca2+ concentrations (less than 2.5 X 10(-7) M) the enzyme was highly activated by phorbol 12-myristate 13-acetate (PMA) or diolein in the presence of phosphatidylserine. It was demonstrated that PMA stimulation of human polymorphonuclear leukocytes did not induce any increase in the level of the intracellular free calcium concentration. It was concluded that PMA activation of protein kinase C occurred independently of a rise in the intracellular Ca2+ concentration. K0.5 (half-maximal activation) for the PMA activation of purified protein kinase C was shown to be equivalent to the K0.5 for PMA stimulation of superoxide (O-2) production in human polymorphonuclear leukocytes, suggesting that protein kinase C is involved in activation of the NADPH oxidase. The presumed intracellular Ca2+ antagonist TMB-8 inhibited the PMA-induced superoxide production, but neither by an intracellular Ca2+ antagonism nor by a direct inhibition of protein kinase C activity.

The effect of preoperative nutrition on the immune system

In many surgical departments it has been common practice to give patients with weight loss pre-operative parenteral nutrition before major surgery. The purpose of the present study was to elucidate the value of intravenous pre-operative nutrition in relation to the immune system. The study comprised 10 patients undergoing total gastrectomy. All patients had a weight loss of 15% of body weight or more within 6 months or 10% within 3 months. Before operation they all received parenteral nutrition for 1 week. They all had 1.5 g of protein per kg per day and energy corresponding to the basal metabolic rate + 50% as Vamin, Intralipid, and carbohydrate solutions. Before and after this treatment blood samples were taken to estimate neutrophil function (the rate of oxygen consumption and superoxide liberation, phagocytosis and intracellular lysis of Candida albicans, the concentration and consumption rate of ATP during phagocytosis, and chemotaxis) and immune globulins (IgG, IgM, & IgA). Cellular immunity (CMI) was estimated by intradermal application of seven different antigens. We found a significant increase in response to the intradermal antigens (p < 0.01) but no difference in any of the parameters expressing leukocyte function or immune globulins.

Respiratory burst oxidase from human neutrophils: purification and some properties

The respiratory burst oxidase of human neutrophils was purified by "dye-affinity" chromatography over a red agarose column. Electrophoresis of the purified enzyme on NaDodSO4 gel showed a single major band at 64,000-66,000 daltons, together with some minor contaminants. On a nondenaturing gel, the enzyme ran as two closely spaced bands, the faster of which contained flavin. When these two bands were rerun separately on a NaDodSO4 gel, they gave identical patterns, each showing a major band at ca. 65,000 daltons. The specific activity (mean +/- SEM) of the purified enzyme was 8.8 +/- 3.5 mumol of O-2 per min/mg of protein.

Chronic granulomatous disease associated with chronic glomerulonephritis

A boy with chronic granulomatous disease (CGD) developed glomerulonephritis at the age of 12 years. The glomerulonephritis progressed to terminal uraemia at age 15 when maintenance haemodialysis was started. The clinical course was complicated by pulmonary aspergillosis and Pseudomonas septicaemia from which he eventually died. The glomerulonephritis was of unknown origin, and a possible relationship between CGD and glomerulonephritis is discussed.

Proton secretion by stimulated neutrophils. Significance of hexose monophosphate shunt activity as source of electrons and protons for the respiratory burst

Phagocytosis by neutrophils is accompanied by a burst in O2 consumption and activation of the hexose monophosphate shunt (HMPS). Proton secretion equal to the amount of O2 consumed is an additional feature of the respiratory burst, but its source has not been identified, nor has the source of all electrons donated to O2 in the respiratory burst. We chemically quantitated total CO2 generation in human neutrophils and found that proton secretion elicited by phagocytosis was accompanied by a stoichiometric increase in CO2 generation. Addition of carbonic anhydrase and its inhibitors had no effect on either the quantities of CO2 measured or the quantities of protons secreted. Therefore, the CO2 generated in the respiratory burst of stimulated neutrophils is hydrated to form H2CO3, which then dissociates, accounting for the observed proton secretion. Furthermore, the CO2 generated corresponds to the O2 consumed with a respiratory quotient of nearly 1. We conclude on the basis of this and previous studies that the HMPS activity is the source of both the electrons for the NADPH oxidase and of protons secreted in association with the respiratory burst.

Subcellular localization of the b-cytochrome component of the human neutrophil microbicidal oxidase: translocation during activation

We describe a new method for subcellular fractionation of human neutrophils. Neutrophils were disrupted by nitrogen cavitation and the nuclei removed by centrifugation. The postnuclear supernatant was applied on top of a discontinuous Percoll density gradient. Centrifugation for 15 min at 48,000 g resulted in complete separation of plasma membranes, azurophil granules, and specific granules. As determined by ultrastructure and the distribution of biochemical markers of these organelles, approximately 90% of the b-cytochrome in unstimulated cells was recovered from the band containing the specific granules and was shown to be in or tightly associated with the membrane. During stimulation of intact neutrophils with phorbol myristate acetate or the ionophore A23187, we observed translocation of 40-75% of the b-cytochrome to the plasma membrane. The extent of this translocation closely paralleled release of the specific granule marker, vitamin B12-binding protein. These data indicate that the b-cytochrome is in the membrane of the specific granules of unstimulated neutrophils and that stimulus-induced fusion of these granules with the plasma membrane results in a translocation of the cytochrome. Our observations provide a basis for the assembly of the microbicidal oxidase of the human neutrophil.

A variant form of X-linked chronic granulomatous disease with normal nitroblue tetrazolium slide test and cytochrome b

Chronic granulomatous disease was diagnosed in a boy who suffered from severe generalized infections. Family investigations revealed the inheritance of the disease to be X-linked. However, unlike other cases of X-linked chronic granulomatous disease, the membrane oxidase of the neutrophils from this patient was not totally defective and sufficient activity was left to result in a normal phorbol myristate acetate-stimulated nitroblue tetrazolium slide test. Also, unlike the usual findings in X-linked chronic granulomatous disease, cytochrome b was present in normal amounts in the neutrophils from this patient. The cytochrome was normal, judged from its midpoint potential of -245 mV and its ability to bind CO. It is thus apparent that X-linked chronic granulomatous disease may result from at least two different defects and that the phorbol myristate acetate stimulated nitroblue tetrazolium slide test fails to detect some cases.

On the mechanism of enhanced monocyte and neutrophil cytotoxicity in severe psoriasis

Monocyte and neutrophil function assessed as antibody-dependent cell-mediated cytotoxicity (ADCC) using IgG-sensitizing human erythrocytes as target cells was enhanced in patients with severe psoriasis when compared to healthy controls. We found significant correlation between increased monocyte ADCC and increased neutrophil ADCC, No differences in basal cAMP levels and cAMP responses during initiation of the ADCC reaction was observed between psoriatics and normals. Also degranulation determined as lysozyme release during ADCC was normal. In contrast, the increase in ADCC was significantly correlated to an enhanced hexose monophosphate shunt activation in the effector cells during the cytotoxic reaction. Activity of enzymes responsible for the respiratory burst was not altered in psoriasis since superoxide production after stimulation with phorbol myristate acetate was normal. Likewise, oxygen consumption and degranulation following phagocytosis of opsonized zymosan particles in neutrophils was found normal in psoriasis. Since monocytes showed increased binding of IgG-sensitized erythrocytes these data indicate that the enhanced monocyte and neutrophil ADCC is caused by an enhancement of the respiratory burst possibly induced by increased Fc receptor activity.

Intrinsic dichlorophenolindophenol reductase activity associated with the superoxide-generating oxidoreductase of human granulocytes

NADPH-dependent dichlorophenolindophenol (DCIP) reductase activity cosediments with NADPH-dependent O(2-)-generating activity in subcellular particulate fractions of zymosan-stimulated human polymorphonuclear leukocytes (PMN's). Subcellular fractions derived from unstimulated PMN's were devoid of both activities, as were fractions from zymosan-stimulated PMN's of a patient known to have chronic granulomatous disease. NADPH-dependent DCIP reduction associated with the oxidoreductase-rich subcellular fractions was unaffected by addition of excess superoxide dismutase sufficient to abolish all traces of O2- production as measured by conversion of ferricytochrome c to its ferrous form. Moreover, DCIP inhibited NADPH-dependent production of O2- in subcellular fractions derived from normal donors. In contrast to the subcellular studies, whole cell suspensions were ineffective in reducing extracellular DCIP despite their capacity to generate O2-, albeit at a lesser rate, in the presence of this electron-accepting dye. These results demonstrate that DCIP reductase activity is associated with the oxidoreductase complex and suggest that it is located on the inner side of the PMN's plasma membrane. The stability of the oxidoreductase complex is markedly improved by storage in glycerol. Both overall O(2-)-generating activity and DCIP reductase activity exhibit a similar pH optimum of 7.0. The Km of the oxidoreductase complex for DCIP is 33 micro M.

Current view of neutrophil dysfunction: an integrated clinical perspective

Normal neutrophil function is dependent on the integration of chemotaxis, phagocytosis, degranulation and oxidative metabolism. The availability of in vitro assays for the separate quantitative evaluation of each function has permitted the definition of specific congenital and acquired neutrophil abnormalities, which are associated with defective host resistance. The appreciation of complex and often adverse effects of certain systemic diseases and drugs on neutrophil function as well as the use of new approaches to therapy suggest the importance of assessing the role of the neutrophil in states of impaired host defense.

Monocyte alpha-naphtyl esterase deficiency in chronic granulomatous disease

Monocytes from five unrelated children (four boys and a girl) with chronic granulomatous disease were studied for their ability to reduce nitroblue tetrazolium dye after stimulation with zymosan, and for their alpha-naphtyl butyrate esterase activity. As expected, monocytes ingested zymosan particles but failed to reduce nitroblue tetrazolium dye. However, monocytes from two boys out of the five patients were alpha-naphtyl butyrate esterase-negative, whereas both their neutrophils and monocytes were positive for granular naphtol AS-D esterase activity.

Chemiluminescence and superoxide anion production by leukocytes from chronic hemodialysis patients

During phagocytosis or in response to a soluble stimulus, polymorphonuclear leukocytes (PMN) undergo a burst of oxidative metabolism involved intimately in antimicrobial activity. Superoxide anion produced during the burst is bactericidal either directly or as an intermediate metabolite. In addition, stimulated PMN's emit light or chemiluminescence (CL). CL is a sensitive measure of PMN oxidative potential and correlates with antimicrobial activity. Because of the increased susceptibility to infection observed in patients on chronic hemodialysis (CHD), we studied superoxide anion production and luminol-amplified CL in PMN's from CHD patients and in age-matched controls in the resting state and in response to phorbol myristate acetate (PMA). Studies in autologous serum showed higher CL resting values in PMN's from CHD patients, and crossincubation studies indicated that this is a result of factor(s) in the patients' serum. In response to PMA, PMN's from patients on CHD in autologous serum had significantly (P less than 0.05) less of an increase (phorbol-stimulated minus resting values) in CL as compared with controls (peak time values, 60 +/- 5 x 10(3) cpm for patients vs. 76 +/- 5 x 10(3) cpm for controls). With crossincubation studies, these differences persisted, suggesting that there is a defect intrinsic to the patient PMN. Studies done after dialysis showed a significant reduction in resting values. The decreased response to PMA stimulation remained, however. No difference in superoxide anion production (superoxide-dismutase-inhibitable ferricytochrome c reduction) was seen in PMN's from patients on CHD compared with controls. This along with other studies indicating normal nitroblue tetrazolium (NBT) reduction in PMN's from CHD patients indicates that the decreased CL is due to superoxide-anion-independent mechanisms. Because CL correlates well with antimicrobial activity, the reduced response to PMA observed in neutrophils from patients on CHD may explain, at least in part, the increased susceptibility to infection in these patients.