Luminol-amplified chemiluminescence: a sensitive method for detecting the carrier state in chronic granulomatous disease

Peritoneal Defense Using Icodextrin Or Glucose for Daytime Dwell in Ccpd Patients

Objective

To investigate peritoneal defense during icodextrin use in continuous cyclic peritoneal dialysis (CCPD).

Design

In an open, prospective, 2-year follow-up study, CCPD patients were randomized to either glucose (Glu) or icodextrin (Ico) for their long daytime dwell.

Setting

University hospital and teaching hospital.

Patients

Both established and patients new to CCPD were included. A life expectancy of more than 2 years, a stable clinical condition, and written informed consent were necessary before entry. Patients aged under 18 years, those who had peritonitis in the previous month, and women of childbearing potential, unless taking adequate contraceptive precautions, were excluded. Thirty-eight patients (19 Glu, 19 Ico) started the study. The median follow-up was 16 and 17 months for Glu and Ico respectively (range 0.5 – 25 months and 5 – 25 months, respectively).

Outcome Measures

Peritoneal defense characteristics and peritoneal dialysis-related infections were recorded every 3 months.

Results

Total peritoneal white cell count tended to decrease over time in both groups. After 1 year, absolute numbers and percentages of effluent peritoneal macrophages (PMΦs) were significantly higher in Ico than in Glu patients; this difference in the percentage persisted after 2 years. Percentage of mesothelial cells increased over time in Ico patients. The phagocytic capacity of PMΦs decreased over time, resulting in a borderline significant difference for coagulase-negative staphylococci ( p = 0.05) and a significant difference for Escherichia coli ( p < 0.05) phagocytosis in favor of Ico patients. PMΦ oxidative metabolism remained stable over time without a difference between the groups. PMΦ cytokine production and effluent opsonic capacity also remained stable over time. Finally, 16 peritonitis episodes in Glu and 14 in Ico patients occurred. Glucose patients had 37 and Ico patients 32 exit-site infections during the study.

Conclusion

CCPD patients using Ico did equally as well as Glu-treated patients with respect to clinical infections and most peritoneal defense characteristics. However, in a few peritoneal defense tests, Ico-treated patients did better.

Posthuma N, Ter Wee PM, Donker AJM, Oe PL, Peers EM, Verbrugh HA. Assessment of the Effectiveness, Safety, and Biocompatibility of Icodextrin in Automated Peritoneal Dialysis

Objective

Our study assessed the efficacy, safety, and biocompatibility of icodextrin (I) solution compared to glucose (G) solution as the daytime dwell in continuous cycling peritoneal dialysis (CCPD).

Design

In a randomized, open, prospective, parallel group study of two years’ duration, either I or G was used for the long daytime dwell in CCPD patients.

Method

The study was carried out in a university hospital and teaching hospital. Established CCPD patients and patients new to the modality were both included. Clinic visits were made at three-month intervals. In all patients, clinical data were gathered; ultrafiltration (UF) was recorded; and serum, urine, and dialysate samples and effluents were collected. Peritoneal defense characteristics and mesothelial markers were determined. Every six months, peritoneal kinetics studies were performed, and serum samples for icodextrin metabolites were taken.

Results

Thirty-eight patients (19 G, 19 I) started the study. The median follow-up was 16 months and 17 months respectively (range: 0.5 – 26 months and 3 – 26 months, respectively). Daytime UF volumes increased significantly (p < 0.001), and 24-hour UF tended to increase from baseline in the I group. Dialysate creatinine clearance increased non significantly in both groups over time. In I patients, serum disaccharides (maltose) concentration increased from 0.05 ± 0.01 mg/mL [mean ± standard error of mean (SEM)] at baseline, to an average concentration in the follow-up visits of 1.15 ± 0.04 mg/mL (p < 0.001). At the same time, serum sodium levels decreased from 138.1 ± 0.7 mmol/L to an average concentration in the follow-up visits of 135.9 ± 0.8 mmol/L (p < 0.05). At 12 months, the serum sodium concentration increased to a non significant difference from baseline. Serum osmolality increased, but did not differ significantly from G users at any visit. During peritonitis (P), daytime dwell UF decreased significantly compared to non peritonitis (NP) episodes in G patients (p < 0.001), but remained stable in I patients. Total 24-hour UF also decreased in G patients (p < 0.001), but not in I patients. In these I patients, serum disaccharides increased from 0.05 ± 0.01 mg/mL to 1.26 ± 0.2 mg/mL during follow-up. During peritonitis, serum disaccharides concentration did not increase further (1.47 ± 0.2 mg/mL, p = 0.56). Thirty P episodes occurred during follow-up: 16 in G patients and 14 in I patients (1 per 17.6 months and 1 per 21.9 months, respectively). After one year, absolute number and percentage of effluent peritoneal macrophages (PMΦs) were significantly higher in I patients than in G patients. The difference in percentage persisted after two years. The phagocytic capacity of PMΦs decreased over time, resulting in a borderline significant difference for coagulase-negative staphylococci phagocytosis (p = 0.05) and a significant difference for E. coli phagocytosis (p < 0.05) in favor of I patients. PMΦ oxidative metabolism, PMΦ cytokine production, and effluent opsonic capacity remained stable over time with no difference between the groups. Mass transfer area coefficients (MTACs) and clearances were stable and appeared unaffected by G or I treatment. Effluent cancer antigen 125 (CA125) was stable in G users and tended to decrease in I users. Effluent interleukin-8 (IL-8), carboxy-terminal propeptide of type I procollagen (PICP), and amino-terminal propeptide of type III procollagen (PIIINP) did not change over time and did not differ between the groups.

Conclusions

The use of I for the long daytime dwell in CCPD led to an increase in total UF of at least 261 mL per day, which was maintained over at least 24 months. During I treatment, serum I metabolites increased significantly and serum sodium concentrations decreased initially. As a result, serum osmolality increased slightly. Clinical adverse effects did not accompany these findings. The UF gain in the I patients was even higher during P, without a further increase in serum I metabolites. CCPD patients using I did equally well as G-treated patients with regard to clinical infections and most peritoneal defense characteristics. However, in a few peritoneal defense tests, I-treated patients did better. Peritoneal transport variables did not change over time. Peritoneal membrane markers did not change throughout the study and did not differ between the groups.

Protective role of carbon dioxide (CO2) in generation of reactive oxygen species

The results testify to the fact that CO2 is a powerful inhibitor of reactive oxygen species (ROS) generation by cells (blood phagocytes and alveolar macrophages of 96 people and cells of inner organs and tissue phagocytes (of liver, brain, myocardium, lungs, kidneys, stomach, and skeleton muscles), as well as by mitochondria of the liver of 186 white mice and human tissues. Generation of ROS was determined using various methods with CO2 directly acting on the cells and bioptates and indirectly on the organism as a whole. CO2 in the concentration of 5.1% (P = 37.5 mmHg), 8.2% (P = 60.0 mmHg), and 20% (P = 146.0 mmHg) in a mixture with air (total pressure = 730 mmHg) inhibits the basal ROS generation by phagocytes on the average by 3.52, 5.69, and 10.03 times, respectively (p < 0.05), and the stimulated by corpuscular particles: (a) zymosan by 3.24, 4.43, and 7.95 times; (b)SiO2: by 2.99, 3.24, and 5.76 times (p < 0.05). This is confirmed by the feet that CO2, along with inhibiting the O2 (-) generation by cells of the various organs, including the liver, as a rule, by 2.19-4.7 times, p < 0.01 or <0.001 induces simultaneously a decrease in the O2 (-) generation by mitochondria isolated from the liver (by 1.91-3.2 times, p < 0.001). The mechanism of CO2 influence is realized, in part, by inhibition of NADPH-oxidase activity. Taken into consideration proven role of CO2 in different pathophysiological conditions, (such as endoarteritis, bronchial asthma, and infectious diseases), present findings may be of clinical interest in terms of potential implementation of CO2 donors as adjuvant therapeutics in these diseases.

Particle-induced myeloperoxidase release in serially diluted whole blood quantifies the number and the phagocytic activity of blood neutrophils and opsonization capacity of plasma

Luminol-amplified chemiluminescence (CL) from phagocytes has previously been shown to be almost completely dependent on the release of myeloperoxidase (MPO) from azurophilic granules. We measured the luminol-amplified chemiluminescence response (WBCL) by using serially diluted whole blood. In these experiments, non-opsonized and serum-opsonized zymosan (NWBCL and OWBCL, respectively) were used concurrently as phagocytosable particles. We found two whole-blood dilution ranges with clinical significance: first, <0.04% of whole blood in the reaction volume, where MPO released by the zymosan-activated leukocyte population came almost totally from neutrophils and the OWBCL response could be exploited as a measure of a neutrophil count in a given blood specimen, despite the pathophysiological state of the host. In contrast, the NWBCL response was two-fold in blood samples from bacterial infection patients compared to those of controls and patients with viral infection, suggesting the use of NWBCL for the differential diagnosis of bacterial infections from viral infections; second, 0.16-1.2% of whole blood in the reaction volume, where the opsonization capacity of plasma (OC(50)) can be determined. We also found that at whole blood content >0.04%, erythrocytes quickly start to absorb chemiluminescence light, and that at whole blood content >1.2%, plasma proteins, most probably albumin and fibrinogen, start to inhibit MPO release.

Granulocyte function disorders: aspects of development, genetics and management

The field of phagocytic disorders has attained major biologic and clinical significance in the past 40 years. The development of exciting new techniques in molecular biology and the cellular physiology of signal transduction have made it possible to identify the genetic defects involved in many of these disorders. Moreover through immunopharmacologic intervention, bone marrow or peripheral or cord blood stem cell transplantation along with the prospect of gene therapy, we have begun attempts to at least partially correct genetic defects in cell development and activation pathways in the entire spectrum of phagocyte disorders. Carrier detection and prenatal diagnosis employing with chain reaction techniques or direct nucleotide sequencing in fetal blood have made these diseases potentially preventable or treatable in utero or shortly after birth.

Evaluation of immunomodulatory effects of nisin-containing diets on mice

The effect of nisin on the immune response of mice was studied. Nisin (in the form of the commercial preparation Nisaplin) was incorporated in the diet of experimental mice which were fed for 30, 75 or 100 days. Short-term administration of diets containing Nisaplin induced an increase of both CD4 and CD8 T-lymphocyte cell counts and also a decrease of B-lymphocyte counts. After prolonged diet administration, T-cell counts returned to control levels. Normal levels of B-lymphocytes were also reached after prolonged administration of the lower (but not the higher) Nisaplin concentration. The macrophage/monocyte fraction isolated from peripheral blood became significantly increased after long-term administration (100 days) of Nisaplin-containing diets in a concentration-dependent way. Although the number of peritoneal cells was not affected by the diets, the phagocytic activity of peritoneal cells decreased after prolonged administration of low (but not high) Nisaplin doses.

Inhibitory effects of resveratrol analogs on unopsonized zymosan-induced oxygen radical production

Resveratrol, a natural hydroxystilbene, has been reported to have anti-inflammatory and anticarcinogenic activities. Inhibitory effects of resveratrol and its analogs on reactive oxygen species (ROS) production in unopsonized zymosan-stimulated murine macrophage Raw264.7 cells, human monocytes, and neutrophils were analyzed to investigate if the anti-inflammatory and anticarcinogenic activities of resveratrol are related to the inhibition of ROS production. Resveratrol was a potent inhibitor of ROS production in both unopsonized zymosan-stimulated Raw264.7 cells and human monocytes and neutrophils. Resveratrol exhibited 50% inhibition values (IC50) of 17 microM in activated Raw264.7 cells, 18 microM in human monocytes, and 23 microM in human neutrophils. 3,5-Dihydroxy-4'-methoxystilbene or 3,4'-dimethoxy-5-hydroxystilbene exhibited IC50 values of 63 or 73 microM in Raw264.7 cells, 51 or >100 microM in human monocytes, and 10 or 37 microM in human neutrophils, respectively. Trimethylresveratrol, piceid, and 3,5-dihydroxy-4'-methoxystilbene-3-O-beta-D-glucoside were weak inhibitors of ROS production. Thus, resveratrol was identified as a potent inhibitor of ROS production, which might be one biochemical mechanism related to its anti-inflammatory and anticarcinogenic activities. The number and position of hydroxy substituents in resveratrol analogs seem to play an important role in the inhibitory potency of ROS production.

Effects of in vivo administration of G-CSF on neutrophil functions in healthy volunteers

The aim of the present study was to investigate the in vivo effects of granulocyte colony-stimulating factor (G-CSF) on neutrophil (PMN) function. G-CSF was administered once daily as s.c. injection for 6 d (d1-6) to healthy male volunteers. PMN migration (modified Boyden chamber), chemiluminescence (CL), adherence to nylon fibers and phagocytosis of IgG- and IgG-C3-coated particles were investigated before (d1), during (d2, d5) and 3 wk after G-CSF 7.5-10 micrograms/kg/d (n = 12). PMN surface expression of adhesion- and Fc gamma-receptors was measured on d1, d5, d8 and 3 wk after G-CSF 3-5 micrograms/kg (n = 12). Results obtained after G-CSF were compared to baseline using Wilcoxon's signed rank test. G-CSF induced PMNs showed a significantly (p < 0.05) decreased chemokinetic response (d5) as well as a reduced chemotaxis towards zymosan activated serum, FMLP and IL-8, respectively. Chemotaxis was reduced both at d2 and d5. Neutrophil adherence, phagocytosis and luminol-enhanced CL increased, whereas G-CSF had no effect on lucigenin-enhanced CL. G-CSF (3-5 micrograms/kg) caused an enhanced expression of CD11b, CD18, CD35, CD64 (Fc gamma RI) and CD32 (Fc gamma RII), respectively. We conclude that neutrophils produced in response to G-CSF have a reduced chemotaxis but an enhanced adherence and phagocytic capacity. G-CSF in vivo does not stimulate the respiratory burst.

Determination of the rate of superoxide generation from biological systems by spin trapping: use of rapid oxygen depletion to measure the decay rate of spin adducts

A method was developed to measure the superoxide generation rate from biological systems using the spin trapping method. Kinetic treatment of the decay rate of the superoxide adduct of 5,5-dimethylpyrroline N-oxide (DMPO) revealed that the EPR signal intensity of the system is proportional to the superoxide generation rate. Rapid depletion of oxygen in the sample was utilized to terminate superoxide generation so that the decay rate of the DMPO superoxide adduct (DMPO-OOH) could be determined. For this decay measurement, a controlled atmosphere EPR cavity was developed and was used with an open-air sample cell. Superoxide generation rates determined with this method for stimulated neutrophils and for the hypoxanthine-xanthine oxidase system were comparable to those obtained with the cytochrome c reduction method. This method is specifically applicable to the system in which dissolved oxygen supplied from the gas phase is utilized as a source of superoxide.

Ethanol stimulates chemiluminescence from neutrophils in the liver

The production of free radicals in tissues can be continually monitored by measurement of low-level chemiluminescence. In these experiments the effects of ethanol on luminol (1 microM)-enhanced chemiluminescence were recorded in isolated perfused livers from control rats, and from rats that had undergone a 30-min period of ischemia, followed by 3 h of reinstitution of blood flow. Our previous experiments showed considerable neutrophil accumulation at this time. A routine concentration of 100 mM ethanol added after 20 min of perfusion with Krebs-Henseleit solution caused an increase in chemiluminescence of about 2000 cpm above the resting level (1600 cpm) in both control livers and livers from rats after 3 h of ischemia reperfusion in vivo. However, if ethanol was added to the perfusing medium of the isolated liver after at least 1 h of in vitro perfusion, then the magnitude of the response was very much greater (peak approximately 27000 cpm) in livers that had undergone ischemia reperfusion than in control livers (peak approximately 7000 cpm). Experiments combining addition of ethanol and the potent neutrophil stimulator, phorbol myristate acetate (PMA), plus the use of rat antineutrophil serum have shown conclusively that the very large chemiluminescent response to ethanol after prolonged in vitro perfusion is due to stimulation of neutrophil radical production.

Chemiluminescent response to PMA in isolated rat liver after in situ ischemia-reperfusion

The median and left lateral lobes of rat liver in situ were rendered ischemic for 30 min, then blood flow reinstituted. After 1, 3, 6, 24, or 48 h, livers were removed and set up for isolated perfused organ study. Luminol enhanced chemiluminescence (LEC) was recorded from the surface of the median and left lateral lobes before and for 90 min following phorbol myristate acetate (PMA, 1.6 x 10(-8) M) perfusion. An increase in PMA induced LEC was evident at 1 h and continued to increase up to 6 h. By 24 h the magnitude of the PMA response had returned to within control values. This indicates that a large influx of inflammatory cells had occurred in the liver following the in vivo ischemia-reperfusion insult and that these cells were well fixed in the tissue and capable of mounting a very large and sustained burst of radical production on stimulation with PMA. This combined in vivo/in vitro technique is ideally suited for the assessment of interventions designed to ameliorate damage following oxidative stress.

Biocompatibility of a glucose-polymer-containing peritoneal dialysis fluid

The currently available glucose-containing peritoneal dialysis fluids (PDF), which are all hyperosmolar, are toxic to the cells present in the peritoneal cavity. However, glucose-polymer solutions, being isosmolar, may have improved biocompatibility in this respect. We therefore compared in vitro the effects of PDF containing glucose-polymers with that of glucose solutions on the function of donor granulocytes and monocytes (MN), and on the viability of mesothelial cells. In addition, the function of peritoneal macrophages (PMO) of eight patients was studied in a randomized cross-over setting following intraperitoneal exposure to glucose-polymer-versus glucose-monomer-containing fluid of comparable ultrafiltration capacity. Donor granulocytes, as well as MN, showed significantly better phagocytosis of both Staphylococcus epidermidis and Escherichia coli after incubation in the glucose-polymer solution as compared with the 3.86% glucose-containing fluid. Their oxidative metabolism, as measured by chemiluminescence, also showed that the glucose-polymer solution was less inhibitory than fluids containing 2.27 or 3.86% glucose. Patient-derived PMO showed a significantly better phagocytic capacity for S epidermidis and E coli, a significantly higher killing of E coli, and a significantly higher chemiluminescence response after intraperitoneal exposure to the glucose-polymer solution as compared with the glucose-monomer-based fluid. Increasing the osmolality of the glucose-polymer solution to that of the respective glucose solutions blunted the favorable effect on phagocyte function, suggesting the beneficial effect to be osmolality-mediated. However, no major difference was observed between the glucose-polymer solution and the glucose-based fluid in their effects on mesothelial viability.(ABSTRACT TRUNCATED AT 250 WORDS)

Photon emission of phagocytes in relation to stress and disease

Phagocytes, the first-line cells of the body's defence mechanisms against invading pathogens, kill microorganisms by means of lysosomal degradative enzymes and highly toxic reactive oxygen intermediates. The reactive oxygen compounds are produced, in a process called the 'respiratory burst', by the NADPH oxidase complex in plasma membranes, and by myeloperoxidase in phagolysosomes after degranulation. These processes generate electronically excited states which, on relaxation, emit photons, giving rise to phagocyte chemiluminescence (CL). This paper describes the conditions for the measurement of CL, and reviews the activity of phagocytes from individuals undergoing stress or disease. The capability of phagocytes to emit photons reflects remarkably well the pathophysiological state of the host. In many cases even the magnitude of the stress, the presence of a pathogen in the body, or the activity of the disease can be estimated. Physiological changes, e.g. in the reproductive cycle, can also be predicted.

Peritoneal defense in continuous ambulatory versus continuous cyclic peritoneal dialysis

Several centers have reported a lower rate of peritonitis among adult patients on continuous cyclic peritoneal dialysis (CCPD) as compared to those undergoing continuous ambulatory peritoneal dialysis (CAPD). Preliminary results of our ongoing prospective randomized study comparing CAPD-Y with CCPD also suggest a lower peritonitis incidence among CCPD-treated patients. To investigate whether the two dialysis regimens could result in differences in local host defense, we studied peritoneal macrophage (PMO) function and effluent opsonic activity in eight patients established on CAPD-Y matched with eight chronic CCPD patients. Since short and long dwell times are inherent to both dialysis modalities, and we previously found that dwell time has an impact on PMO function and effluent opsonic activity, patients were studied after both a short (4 hr) and a long (15 hr) dwell time. In both groups PMO phagocytic capacity increased significantly with dwell time (39 +/- 3.3% at 4 hr vs. 58 +/- 4.2% at 15 hr in CAPD patients, and 40 +/- 3.9 vs. 72 +/- 3.3% in CCPD patients; P less than 0.01), as did PMO peak chemiluminescence response (31 +/- 4.9 vs. 77 +/- 7.2 counts.min-1/10(4) cells in CAPD, and 22 +/- 3.9 vs. 109 +/- 21.2 counts.min-1/10(4) cells in CCPD; P less than 0.01) and effluent opsonic activity (41 +/- 7.6 vs. 73 +/- 5.8% in CAPD and 39 +/- 6.2 vs. 70 +/- 5.9% in CCPD; P less than 0.01). However, no significant difference was found in either variable between CAPD and CCPD patients when dwell times were equal.(ABSTRACT TRUNCATED AT 250 WORDS)

On radical production by PMA-stimulated neutrophils as monitored by luminol-amplified chemiluminescence

The means by which neutrophils within the body ward off infectious and neoplastic processes by the activation of molecular oxygen, as well as how such mechanisms dysfunction, is the subject of extensive ongoing research. Most previous studies of neutrophil activation indicate that there is a transient production of reactive oxygen species. Luminol-amplified chemiluminescence surveillance of O2-. and H2O2 supported these general findings. Yet, recent studies showed that production of reactive oxygen species by PMA-stimulated neutrophils is not transient but persistent; however, luminol-dependent methods do not corroborate such findings. The kinetics of O2-. production by human neutrophils were studied using luminol-amplified chemiluminescence (CL), spin trapping combined with electron spin resonance detection, and ferricytochrome c reduction. The effects of pH and O2 level on luminol-amplified CL were determined using hypoxanthine/xanthine oxidase to produce O2-. and H2O2 in cell-free systems. As we have found by electron spin resonance and ferricytochrome c reduction, stimulated neutrophils continued to generate O2-. for several hours, yet when luminol-amplified CL was used to continuously follow radical production, CL was shortly lost. Similar loss of CL was observed with continuous enzymatic formation of O2-. and H2O2. The failure of the CL assay to report O2-. and H2O2 formation results from some luminol reaction product which interferes with the light reaction. Our results show that the cells are operative for long periods indicating that cell exposure to prolonged O2-. fluxes does not terminate radical production, and even when pH, [O2], and reagents are optimized, the use of luminol-amplified CL is not a valid assay for continuous monitoring of O2-. and H2O2 generated by either stimulated neutrophils or in cell-free systems.

Correlation between neutrophil superoxide formation, luminol-augmented chemiluminescence and intracellular Ca2+ levels upon stimulation with leukotriene B4, formylpeptide and phorbolester

When neutrophils were stimulated with leukotriene B4 (LTB4) .O2- -production and elevation of intracellular Ca2+ were initiated more rapidly than after stimulation with N-formyl-methionyl-leucyl-phenylalanine. Phorbol myristate acetate (PMA) induced a substantially more protracted superoxide (.O-2) production. Luminol augmented chemiluminescence (LCL) reflected the kinetic characteristics accurately. The primary distinguishing attribute of LTB4-induced responses were an initial high rate of activation and a rapid termination. Thus, LTB4-induced neutrophil Ca2+-inflow and .O2- -formation may be initiated by mechanisms similar in part to those for formylpeptides; however it does not possess the ability to maintain this activation. The kinetic properties of neutrophil activation may be studied with LCL, irrespective of the exact nature of the LCL-generating oxidants formed by neutrophils.

Heterogeneity in opsonic requirements of Staphylococcus epidermidis: relative importance of surface hydrophobicity, capsules and slime

The opsonic requirements of 65 strains of Staphylococcus epidermidis were compared in fresh and in heated normal human serum. The strains were isolated from patients with CAPD peritonitis (n = 26), neonatal septicaemia (n = 24) and nasal cultures (n = 15). A wide variation was observed in opsonic requirements between the different strains, both with fresh and with heated serum. Opsonization in heated serum proceeded less efficiently and higher concentrations (mean three-fold compared to fresh serum) were needed for adequate phagocytosis. However, a highly significant correlation was found between the minimal opsonic concentrations of fresh and of heated serum (r = 0.84, P less than 0.0005). In addition, S. epidermidis can become opsonized in agammaglobulinaemic serum. Thus, opsonization of S. epidermidis can be mediated by antibodies alone and by complement alone. Slime-producing strains and encapsulated strains did not require higher concentrations of serum to become opsonized. Opsonic requirements were highly significantly correlated with surface hydrophobicity. Enzymatic treatment rendered the strains more hydrophilic and decreased their opsonic requirements. Isolates from nasal cultures required significantly higher concentrations of both fresh and heated serum to become adequately phagocytozed, whereas isolates from CAPD peritonitis required higher concentrations of heated serum only compared to blood isolates. The uptake of S. epidermidis preopsonized in heated serum as determined in our direct phagocytosis assay did not result in a comparable chemiluminescence response.

Mechanisms for luminol-augmented chemiluminescence from neutrophils induced by leukotriene B4 and N-formyl-methionyl-leucyl-phenylalanine

Neutrophils stimulated with formyl-methionyl-leucyl-phenylalanine (fMLP) or leukotriene B4 (LTB4) generated kinetically distinctive luminol augmented chemiluminescence (LCL). Inhibitors of .O2- [superoxide-dismutase (SOD) or tiron], H2O2 (catalase), myeloperoxidase, MPO, (NaN3), HOCl (taurine) and .OH (mannitol) hampered LCL dose-dependently with similar characteristics for both stimuli. In cell free systems it was found that .O2- (generated in the xanthine/xanthine-oxidase reaction) or H2O2 produced LCL. Superoxide dismutase inhibited .O2- -induced LCL dose dependently. The MPO + H2O2 system, which generated more pronounced LCL than either component alone, was inhibited by catalase and taurine but not by SOD. When neutrophils, treated with luminol, but where extracellular luminol had been removed, were stimulated with fMLP or LTB4, they produced less than 2% of the LCL where luminol was present in the medium. When neutrophil LCL and superoxide formation by the cytochrome C method were assessed in parallel experiments, in all instances the peak LCL response coincided with the linear phase in that response. Thus, LCL, induced by LTB4 and the corresponding fMLP peak, are extracellular events with similar chemical backgrounds, closely related to generation of reactive oxygen species. Consequently, the kinetical differences in LCL between fMLP and LTB4 suggest that LTB4, by yet unknown mechanisms, activates the NADPH oxidase more rapidly than fMLP.

Effect of granulocyte-macrophage colony-stimulating factor on chemiluminescence of human neutrophils

We investigated the capacity of recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF) to enhance the function of neutrophils. Neutrophil function was measured in terms of N-formyl-methionyl-leucyl-phenylalanine (fMLP)-induced luminol-dependent chemiluminescence (LDCL). LDCL of fMLP-stimulated neutrophils was enhanced up to 4.5 fold following preincubation with rhGM-CSF. This enhancement depended on the length of preincubation, reaching an optimal level at 120 min. The dose-response relationship for fMLP-induced LDCL of neutrophils preincubated with rhGM-CSF revealed that half-maximum enhancement was achieved at an approximately 20-fold higher concentration than that of colony-forming units in culture-derived colony formation. These results suggest that differences in dose dependency may be explained by differences in the distribution of receptor(s) for GM-CSF. This may also enable GM-CSF to affect the hematopoietic system, which contains cells at various levels of differentiation, thus mediating the host-defense mechanism.

A reference procedure to study chemiluminescence induced in polymorphonuclear leukocytes by Neisseria meningitidis

Luminol-enhanced chemiluminescence (CL) was used to study the ability of various strains of Neisseria meningitidis (MC) to induce oxidative metabolism of polymorphonuclear leukocytes (PMNL); an indirect measure of phagocytic activity. To circumvent variations related to different PMNL donors, a MC serogroup X strain was used as a control for indexing the CL responses induced by other MC strains. This procedure, with pooled serum from healthy blood donors to standardize opsonising conditions, gave reproducible and comparable results, irrespective of PMNL donors. Under these conditions, there was a highly significant difference between pathogenic and non-pathogenic MC strains as regards their ability to induce CL responses (p less than 0.001). The results indicated that the differences were due partly to opsonizing antibodies, partly to other differences related to pathogenicity of tested MC strains. These differences in leukocyte/MC interaction were also confirmed by phagocytic-killing experiments. The index procedure of CL measurements may be a suitable method to study the appearance of natural immunity to MC disease, as well as the pathogenicity of particular MC strains.

Dialysis fluids and local host resistance in patients on continuous ambulatory peritoneal dialysis

The ability of polymorphonuclear leukocytes, monocytes and peritoneal macrophages to mount a respiratory burst in continuous ambulatory peritoneal dialysis (CAPD) fluids was tested in a phorbol-myristate acetate stimulated chemiluminescence assay. Fresh CAPD fluids depressed the chemiluminescence response of all three types of phagocytes tested to less than 18% of their chemiluminescence response in control buffer. When tested in spent CAPD fluids the suppression of chemiluminescence was 30-32%. Oxygen consumption of polymorphonuclear leukocytes was depressed in fresh CAPD fluids to below 40%. Both phagocytosis of Escherichia coli by and bactericidal capacity of polymorphonuclear leukocytes and monocytes were suppressed in fresh CAPD fluids but not in spent effluents. The influence of acidic pH and hyperosmolality on phagocytic functions were studied separately by modifying the acidity or the glucose content of the control buffer. pH values below 6.0 significantly inhibited chemiluminescence but not phagocytosis. Under hypertonic conditions, both phagocytosis and chemiluminescence were inhibited. We conclude that the currently available CAPD solutions are beyond the limits of acid and osmotic tolerance of human phagocytic cells, and may thus compromise the peritoneal defenses of CAPD patients.

Enhancement of human neutrophil function by platelets: effects of indomethacin

To characterize the influence of presence of platelets on human neutrophil function, neutrophil oxidative burst, chemotaxis, leukotriene B4 and prostacyclin generation were examined in the presence of physiologic concentration of platelets (40: 1). Presence of platelets significantly (P less than or equal to 0.05) increased all these neutrophil functions. To determine if cyclooxygenase products are involved in platelet-neutrophil interaction, neutrophils (+/- platelets) were incubated with indomethacin. Although high concentrations of indomethacin (10 microM) inhibited neutrophil (no platelets) chemotaxis and leukotriene B4 generation, these inhibitory effects of indomethacin were attenuated in the presence of platelets. Thus presence of platelets enhances neutrophil activity and overcomes the inhibitory effects of indomethacin on neutrophils.

Chemiluminescence of canine peripheral blood lymphocytes stimulated by mitogens

Luminol-dependent chemiluminescence of peripheral blood lymphocytes from dogs stimulated with concanavalin A (Con A) or phytohemagglutinin P (PHA) was measured with a Pico-Lite luminometer. 10 microliter of luminol gave optimal quantum yield from 1 X 10(6) lymphocytes sensitized with either 80 micrograms Con A or 160 micrograms PHA. Addition of superoxide dismutase did not influence the course of chemiluminescence. Whereas catalase produced 41% increase in quantum yield, mannitol caused a 51% inhibition of chemiluminescence. Lymphocytes exposed to varying doses of short term x-irradiation or lymphocytes isolated from dogs kept under continuous exposure through a gamma irradiation source showed dose-related depression of chemiluminescence. Membrane factors may be involved in lymphocyte stimulation to chemiluminescence as pulse experiments with Con A and PHA revealed. It is proposed that chemiluminescence measurements may be useful in monitoring early events in lymphocyte stimulation by antigens and mitogens.

Neuraminidase activity is not the cause of influenza virus-induced neutrophil dysfunction

Influenza viruses have been shown to decrease the ability of polymorphonuclear leukocytes (PMN) to respond to a variety of stimuli. This study was done to determine if viral neuraminidase was responsible for decreased PMN function. Treatment of human PMN with purified neuraminidases from influenza virus, Vibrio cholerae, or Clostridium perfringens did not significantly affect the ability of human PMN to respond to stimulation. Occasional virus preparations that lacked the ability to depress PMN function did not differ in neuraminidase activity from viruses capable of causing depression. These results demonstrate that neuraminidase activity is not the cause of influenza virus-induced PMN dysfunction.

Neutrophil chemi-luminescence and opsonic activities of young people with periodontitis in Thailand

The polymorphonuclear neutrophils (PMN) produced significantly-higher chemi-luminescence (CL) peak values than neutrophils of healthy-paired controls when each population of cells was challenged with zymosan pre-opsonized with autologous serum. This enhanced CL was not attributable to the metabolic activity of the cells, but was shown, by cross-over experiments and additional testing with a single source of cells, to be directly associated with the opsonizing capacity of the patient's serum. The results suggest that peripheral PMN from young periodontitis patients have oxidative metabolic activities similar to subjects free of this disease, and that the enhanced PMN metabolism of patients may be due to a corresponding increase of serum opsonins.

The chemiluminescent response of bovine polymorphonuclear leucocytes isolated from milk and blood

Polymorphonuclear leucocytes (PMN) were isolated from milk and blood of healthy cows, and the generation of reactive oxygen by the two cell populations was compared by measuring chemiluminescence (CL) after stimulation with zymosan. The ratio of milk to blood PMN CL was relatively constant in a given animal, but varied widely between different cows, ranging from 0.3 to 1.3. The relative contributions of various oxygen species to CL was studied by measuring quenching using different oxygen scavengers. While the relative contributions of H202, -02 and '02 seemed to be similar in both milk and blood PMN, the OH. radical was clearly more prominent in PMN isolated from milk than from blood. In addition, blood PMN CL was more dependent on the presence of glucose in the reaction medium than milk PMN CL. Furthermore, the CL response to phorbol myristate acetate, to the Ca ionophore A23187 and to Sendai virus was different in the two cell types. The results suggest that CL generation in milk PMN differs from that in blood PMN in quantitative as well as qualitative aspects.

Influence of subinhibitory concentrations of penicillin, cephalothin, and clindamycin on Staphylococcus aureus growth in human phagocytic cells

After an initial 2-h incubation with phagocytic cells, the growth of surviving intracellular Staphylococcus aureus was examined in the presence of subinhibitory concentrations of penicillin, cephalothin, and clindamycin. One-tenth of the minimal inhibitory concentrations of these antibiotics markedly reduced bacterial growth in normal polymorphonuclear leukocytes. In contrast, when human alveolar macrophages were studied, no inhibition of growth was seen. Subinhibitory concentrations of these antibiotics and polymorphonuclear leukocytes acted synergistically to reduce intracellular survival of S. aureus. This synergy did not appear to be dependent upon the microbicidal potential of the leukocyte respiratory burst, since no differences were found when polymorphonuclear leukocytes obtained from patients with chronic granulomatous disease were compared with those from normal donors.

Influenza A virus-induced polymorphonuclear leukocyte dysfunction

Previous studies have shown that influenza A virus can activate the polymorphonuclear leukocyte (PMN) respiratory burst and that upon subsequent stimulation of the cell there is depressed metabolic function. We examined the mechanism by which influenza virus causes PMN dysfunction by measuring the effect upon the chemiluminescent activity of cells of varying the type of influenza virus used, the period of time that cells were exposed to virus, and the secondary stimulus that was used. The various types of intact influenza virus elicited different amounts of chemiluminescent activity, but when cells were subsequently stimulated with phorbol myristate acetate, each virus caused equivalent depression of the PMN response. Purified glycoproteins incorporated into a liposome structure similarly stimulated the PMN chemiluminescence, yet did not induce PMN dysfunction. Depressed PMN function was noted after as little as 5 min of incubation of cells with virus and occurred to both receptor-dependent (zymosan, N-formylmethionyl-leucyl-phenylalanine, and phorbol myristate acetate) and -independent (calcium ionophore A23187) stimuli.

Depression of monocyte and polymorphonuclear leukocyte oxidative metabolism and bactericidal capacity by influenza A virus

Decreased host defense against bacterial disease associated with influenza infection may be related to virus-induced changes in phagocytic cell function. Influenza A virus initiates the respiratory burst in peripheral blood monocytes and polymorphonuclear leukocytes, with a peak chemiluminescent response approximately 3 min after virus is added to the cells in vitro. Electron micrographs of phagocytic cells incubated with influenza virus demonstrated virus attached to the cell membrane and within phagocytic vacuoles. After 20 min of incubation of the virus with phagocytic cells, the chemiluminescent response to opsonized zymosan or phorbol myristate acetate was decreased by 30 to 90%. Phagocytic activity of monocytes and polymorphonuclear leukocytes incubate with influenza virus was normal, but the bactericidal activity was significantly depressed. Influenza A virus therefore stimulates an oxidative burst in monocytes as well as polymorphonuclear leukocytes, leading to a subsequent depression of the oxidative metabolic response and bactericidal capacity of the phagocytic cells.

Recurrent infections and delayed separation of the umbilical cord in an infant with abnormal phagocytic cell locomotion and oxidative response during particle phagocytosis

An 18-month-old infant with delayed separation of the umbilical cord and severe recurrent bacterial infections since the newborn period was found to have depressed polymorphonuclear leukocyte locomotion and oxidative metabolic response to particulate stimuli. Both her polymorphonuclear leukocytes and monocytes demonstrated a markedly delayed chemiluminescence response to zymosan, but there was a normal chemiluminescence response to soluble stimuli, phorbol myristate acetate and calcium ionophore A23187. The patient also had a marked delay in uptake of Staphylococcus aureus and Escherichia coli. The patient's polymorphonuclear leukocytes were normal morphologically, and myeloperoxidase was present in histochemical stains. The dichotomy between normal oxidative response to soluble stimuli and abnormal response to opsonized particulate stimuli, plus abnormal cell locomotion and phagocytosis, suggest an abnormality of cell membrane fluidity or contractility.

Abnormal responses of granulocytes in chronic granulomatous disease

Stimulation of normal granulocytes with chemotactic factor, phorbol myristate acetate, concanavalin A, and calcium ionophore results in rapid depolarization which precedes the 'respiratory burst'. Treatment of granulocytes in chronic granulomatous disease with these stimulants fails to generate chemiluminescence. This defect is associated with an absence of transmembrane potential shifts in response to treatment with chemotactic factor, phorbol myristate acetate, and concanavalin A while depolarization in response to A23187 is unaffected by this disease state.

Chemiluminescence by polymorphonuclear leukocytes adhering to surfaces

Stimulation of the plasma membranes of granulocytes results in an oxidative metabolic response. This response can be measured by measuring the reduction of oxidizable substrates, such as Nitro Blue Tetrazolium, as well as by measuring the energy released as light (chemiluminescence). While investigating the oxidative response of human granulocytes, we observed a marked variation in the chemiluminescence response when leukocytes were suspended in a balanced salt solution without gelatin or any other protein. We performed systematic study to investigate the role of protein in suspensions of human polymorphonuclear leukocytes. Final results were identical with human serum, albumin, fetal calf serum, and gelatin; gelatin was used as the protein source in most experiments. Polymorphonuclear leukocytes suspended in Hanks balanced salt solution without gelatin decreased in numbers during incubation at room temperature (approximately 50 percent after 60 min). Cell structures were observed on the walls of the tubes containing leukocyte suspensions without gelatin. Numbers of polymorphonuclear leukocytes were stable in suspensions containing gelatin. A chemiluminescence response which peaked at approximately 10 min and was sustained for at least 30 min was observed in suspensions of polymorphonuclear leukocytes without gelatin. This surface attachment-stimulated chemiluminescence occurred in the absence of either soluble or particulate stimuli. Chemiluminescence was inhibited by either superoxide dismutase or sodium azide and did not occur with suspensions of granulocytes from patients with chronic granulomatous disease. We postulate that both superoxide- and myeloperoxidase-dependent oxidative metabolic reactions are induced during the adherence of polymorphonuclear leukocytes to surfaces. Gelatin or other proteins in leukocyte suspending media are necessary when assays are performed to evaluate the metabolic responses of these cells to particulate or soluble stimuli.