Chemiluminescence by polymorphonuclear leukocytes adhering to surfaces

Increase in granulocyte-macrophage-colony-stimulating factor secretion and the respiratory burst with decreased L-selectin expression in hyper-IgE syndrome patients

BACKGROUND

The hyper-IgE syndrome is a primary immunodeficiency characterized by severe recurrent abscesses, pneumonia with pneumatocele formation, and elevated serum IgE. Eosinophilia, neutrophil chemotactic defects, and marked tissue damage are frequently present in this syndrome.

OBJECTIVE

To study whether functional changes in cytokines, adhesion molecules, and neutrophils might help explain these clinical observations.

METHODS

The following functions were analyzed in patients with the hyper-IgE syndrome and in controls: (1) production of granulocyte-macrophage-colony-stimulating factor by peripheral blood mononuclear cells by ELISA; (2) respiratory burst and reactive oxygen intermediates production by peripheral neutrophils using the luminol-enhanced chemiluminescense technique; and (3) expression of L-selectin on granulocytes and lymphocytes by flow cytometry.

RESULTS

Patients with hyper-IgE syndrome had significantly increased production of granulocyte-macrophage-colony-stimulating factor by resting or stimulated mononuclear cells, increased generation of reactive oxygen intermediates by neutrophils treated with opsonized zymosan, and reduced L-selectin expression on quiescent and activated granulocytes and lymphocytes.

CONCLUSIONS

Our results suggest that an important feature of the hyper-IgE syndrome is the increased production of granulocyte-macrophage-colony-stimulating factor, which may explain the reduced L-selectin expression, decreased chemotaxis, and increased oxygen radical production and tissue damage in this disease.

A study of granulocyte respiratory burst in patients with allergic bronchial asthma

The respiratory burst of phagocytes plays an important role in the tissue damage that accompanies the inflammatory response. One of these conditions is allergic bronchial asthma, therefore, to evaluate the activation state of peripheral granulocytes the generation of reactive oxygen metabolites was evaluated using Luminol-enhanced chemiluminescence (LCL) and reduction of cytochrome C by superoxide. The resting granulocytes of the asthmatic patients under crisis showed a higher LCL compared to the noncrisis patients and control subjects. The granulocytes stimulated with PMA presented a significant increase in the respiratory burst in both groups of asthmatics. The granulocytes of noncrisis asthmatics challenged with Ops-Zym and with fMLP + Ops-Zym showed a higher metabolic activity, whereas the asthmatics under crisis presented no difference between reactive oxygen generation and that of the control group. The quantitative analysis of superoxide generation by granulocytes of the same patients did not show differences among the groups. Our findings suggest that the granulocytes of crisis and noncrisis asthmatics seem to be in a hyperreactive state and with a higher metabolic response when compared to the control group. However, the patients present a different behavior depending on stimulus used to activate cells. This could indicate that in peripheral blood exist different granulocyte populations depending on the inflammatory response taking place in the respiratory tract.

Luminol enhanced Fc-receptor dependent chemiluminescence from peripheral PMN cells. A methodological study

Maximal luminol enhanced chemiluminescence (CL) of PMN cells after Fc-gamma-receptor stimulation is a way to study the cell activity in connection with phagocytic function. Optimal conditions for such a method were elaborated for practical clinical use. After blood sampling and gentle mixing the blood sample was allowed to stand at +20 degrees C for not more than 1 h. The PMN cells prepared at +20 degrees C were washed at +4 degrees C with a phosphate buffer containing human serum albumin. A gentle lysis of the red blood cells with NH4Cl solution reduced the number of red cells sufficiently not to interfere with the CL. Important factors for the precision of the method were reproducible amounts of bacteria and a reproducible mixing of the particles during the CL analysis. The method had a variation (CV) of 10-15% in healthy individuals.

Immunochemical characterization and biological properties of a cell surface antigen extracted from encapsulated Staphylococcus epidermidis strain SE-10

Protection inducing antigen (PIA) was mechanically extracted from Staphylococcus epidermidis (encapsulated strain SE-10) and purified by DEAE-Sephadex A 25 (C1- form) ion exchange chromatography. Major carbohydrate constituents of PIA were galactose, glucose, and N-acetylglucosamine at the molar ratio 1.00:0.96:0.78. Antigenic activity was considerably reduced after sodium metaperiodate oxidation, however, pronase digestion was not effective. N-acetylglucosamine residues were shown to be closely related to the antigenic determinant. No cross reactivity to PIAs from other encapsulated strains of S. epidermidis was found which indicates type specificity. Protection of mice after immunization and enhancement of human granulocyte function suggests that PIA might be considered to be a biological response modifying substance.

Different influences of cytochalasin B on the activation of human neurophils settled onto petri dishes displayed by simultaneously detected native and luminol-dependent luminescence

Cytochalasin B (CB) is known to interfere reversibly with the cytoplasmic contractile filamental network of mammalian cells. The role of the microfilament system in the mechanism of the reactive oxygen intermediates release of polymorphonuclear leukocytes (PMNL) was studied for different kinds of stimuli. PMNL from fresh human blood were treated with CB and stimulated by adherence on plastic surfaces, by opsonized zymosan, by phorbol myristate acetate and by N-formylmethionyl-phenylalaline. The production of reactive oxygen species were monitored by simultaneous detection of native, luminol-independent, luminescence (NL) and luminol-dependent luminescence (LDL) using a method of spectral discrimination. Different influences of CB on NL with respect to LDL as well stimuli-dependent influences of CB on the luminescence response of PMNL were observed. Especially phagocytosis-associated activation of PMNL was strongly inhibited by CB, whereas LDL was reduced to a much greater extent in comparison with NL. A firm involvement of the microfilament system is indicated, but it depends on the kind of stimulus engaged.

A continuous alveolar macrophage cell line: comparisons with freshly derived alveolar macrophages

Responses of a recently developed rat alveolar macrophage cell (NR8383.1) line were compared to those of freshly derived alveolar macrophages in vitro. Marked inter- and intraspecies heterogeneity in levels of phagocytosis of unopsonized Pseudomonas aeruginosa or zymosan was noted among freshly derived alveolar macrophages from rats, rabbits, and baboons. In contrast, phagocytic responses of alveolar macrophage cell line were predictable and highly reproducible. Similar results were obtained in measuring oxidative burst, as indicated by the production of H2O2 and luminol-enhanced chemiluminescence. Responses were again highly variable in freshly derived alveolar macrophages stimulated with zymosan or phorbol myristic acetate; moreover, freshly derived alveolar macrophages exhibited a wide range of chemiluminescence activity in unstimulated cultures. Results strongly suggest that data derived from the continuous alveolar macrophage culture NR8383.1 can be extrapolated to freshly derived alveolar macrophages of various species, and in many experiments will be useful in avoiding the significant animal-to-animal variance observed among freshly derived cell preparations.

Resistance of mucoid Pseudomonas aeruginosa to nonopsonic phagocytosis by alveolar macrophages in vitro

A unique, recently described rat alveolar macrophage cell line (NR8383) was used to study the interaction of the pulmonary immune system with a mucoid cystic fibrosis isolate of Pseudomonas aeruginosa (SRM-3), its nonmucoid revertant (SRM-3R), and a non-cystic fibrosis isolate (PAO-1). Strain SRM-3 was cultivated in a chemostat system to allow maintenance of an entirely mucoid population. The alveolar macrophage response to the mucoid and nonmucoid strains of P. aeruginosa was determined by visually quantitating phagocytosis in acridine orange-stained monolayers and measuring the induction of an oxidative burst as indicated by chemiluminescence and H2O2 production. In all experiments, fewer than 2% of the NR8383 cells engulfed the mucoid SRM-3 isolate, while SRM-3R and PAO-1 were phagocytized by 15 and 41%, respectively. Opsonization by normal serum (complement) provided minimal phagocytic enhancement of these strains, whereas specific anti-P. aeruginosa antibody slightly elevated phagocytic responses to strains with nonmucoid phenotypes while providing a sevenfold increase in uptake of SRM-3. Chemiluminescent and H2O2 responses were comparable with the levels of phagocytosis observed, with very little or no response to the mucoid strain SRM-3. The data indicate that the strains with mucoid phenotypes are refractile to ingestion and that studies which describe ingestion of mucoid strains were likely measuring ingestion of revertants. Alginic acid (2 mg/ml) was found to inhibit stimulation of macrophage response to the opsonized and unopsonized nonmucoid strain PAO-1.

Regulatory aspects of low intensity photon emission

Photon emission from unicellular and multicellular organisms has been a subject of study for many decennia. In contrast to the well-known phenomenon of bioluminescence originating in luciferin-luciferase reactions, low intensity emission in the visible region of the electromagnetic spectrum has been found in almost every species studied so far. At present, the nomenclature of this phenomenon has not crystallized and it is referred to by a variety of names, such as mitogenetic radiation 29, dark luminescence 7, low-level chemiluminescence 20,36, and biophotons 57. Particular attention has been focussed on the relationship between photon emission and the regulation of various aspects of cellular metabolism, although in many cases quantitative data are still lacking. Throughout the history of this field of research the question of a functional biological role of the low intensity emission has been repeatedly raised; this is reflected, for instance, in the heterogeneity of the terms used to describe it. The discussion concerns the possible participation of photons of low intensity in intra- and intercellular communication. This paper reviews literature on the metabolic regulation of low intensity emission, as well as the regulation of photon emission initiated by external light. Furthermore, recent data are discussed with respect to a possible biocommunicative function of low intensity photon emission.

Inhibition of luminol-dependent luminescence and simultaneous generation of native luminescence of activated human polymorphonuclear leukocytes by addition of albumin

Luminol-dependent luminescence (LDL) and luminol-independent, native luminescence (NL) of polymorphonuclear leukocytes were investigated with respect to the effects generated by the addition of albumin to the reaction medium. The cells were activated: (1) by simple surface attachment to a hydrophilic plastic, (2) by opsonized zymosan, (3) by phorbol myristate acetate, (4) by formylmethionyl-leucyl-phenylalaline. Both kinds of emissions were recorded simultaneously using a method of spectral discrimination. The addition of albumin resulted in an inhibition of LDL, which coincided with a generation of NL. The extent of the inhibition of LDL depended on the type of stimulus used. Maximum inhibition occurred with cells activated by attachment to plastic surfaces and minimum inhibition was observed with cells stimulated by opsonized zymosan. Different contributions of extracellularly released reactive oxygen-species may be responsible for this. It appears possible to discriminate between intra- and extracellular sites of oxygen-metabolites production using albumin simultaneously as extracellular quencher of LDL and as luminescent probe for NL.

Oxidative response of human neutrophils, monocytes, and alveolar macrophages induced by unopsonized surface-adherent Staphylococcus aureus

In contrast to results with bacterial suspensions, phagocytosis of unopsonized bacteria readily occurs when bacteria are adhered to glass or plastic surfaces. However, in contrast to neutrophils, alveolar macrophages produced much less DNA denaturation as measured by acridine orange metachromasia of phagocytized Staphylococcus aureus. We have studied the phagocytosis of unopsonized surface-adherent S. aureus and the subsequent production of reactive oxygen species by peripheral blood neutrophils, monocytes, and alveolar macrophages. Phagocyte-free systems were then used to show the relationship of the reactive oxygen species produced by neutrophils and alveolar macrophages and the denaturation of unopsonized S. aureus DNA with acridine orange. Peripheral blood neutrophils, monocytes, and alveolar macrophages from normal human volunteers were added to vials with adherent S. aureus without opsonin. Bacterial uptake and luminol- and lucigenin-dependent chemiluminescence were measured. Neutrophils developed much greater luminol-dependent chemiluminescence than monocytes or alveolar macrophages. Compared with neutrophils and monocytes, alveolar macrophages developed significantly greater concentrations of superoxide, as measured by lucigenin-dependent chemiluminescence and ferricytochrome c reduction. These findings suggested that products of the myeloperoxidase-hydrogen peroxide-halide pathway were generated when peripheral blood neutrophils were stimulated and that alveolar macrophages primarily produced superoxide. When these reactive oxygen species were generated in phagocyte-free systems containing S. aureus, products of the myeloperoxidase-hydrogen peroxide-halide pathway produced denaturation of S. aureus DNA, whereas superoxide did not. Thus, differences in reactive oxygen species produced during phagocytosis may be related to the different capacities of neutrophils and alveolar macrophages to denature unopsonized adherent S. aureus DNA.

Inhibition of human neutrophil function by 6-aminonicotinamide: the role of the hexose monophosphate shunt in cell activation

Stimulation of polymorphonuclear leukocytes with phorbol myristate acetate (PMA) or chemotactic factors such as f-Met-Leu-Phe (fMLP) activates a membrane oxidase which results in the generation of the superoxide anion (O2-) and the oxidation of NADPH to NADP+. The subsequent reduction of NADP+ to NADPH is believed to be directly dependent upon activation of the hexose monophosphate shunt (HMPS). To further understand the role of the HMPS in the oxidative burst, we examined the kinetics of HMPS activation by fMLP and PMA. Both of these agents stimulate an increase in HMPS activity that parallels their production of O2-. To examine the role of the HMPS in cell activation, we treated polymorphonuclear leukocytes with the specific HMPS inhibitor, 6-aminonicotinamide. This pretreatment inhibited fMLP- and PMA-stimulated HMPS activity and O2- release by 80% and 60% respectively with a 50% inhibitory dose (ID50) of 5 X l0(-7)M. Measurement of reduced NADPH using 350 nm ultraviolet light-stimulated fluorescence and flow cytometry indicated that 6-aminonicotinamide had no effect on resting levels of NADPH fluorescence but significant inhibited the fluorescence recovery following stimulation with fMLP or PMA. In contrast, PMA- and fMLP-stimulated membrane depolarization measured with the carbocyanine dye 3,3'-dihexyloxacarbocyanine iodide and chemotaxis to fMLP were unaffected by 6-aminonicotinamide treatment. On the contrary, fMLP- or PMA-stimulated myeloperoxidase release by fMLP or PMA was enhanced by 30% and 150%, respectively, following treatment with 6-aminonicotinamide, suggesting a decreased oxidative inactivation of myeloperoxidase.(ABSTRACT TRUNCATED AT 250 WORDS)

Chemiluminescence of macrophages depends upon their differentiation stage: dissociation between phagocytosis and oxygen radical release

The in vitro differentiation and maturation of resident and activated mouse and human macrophages (M phi) from different anatomical sources was investigated with regard to their oxygen metabolism during zymosan phagocytosis. We found evidence that chemiluminescence (CL) of M phi depends upon their differentiation stage: a) In the absence of any phagocytic stimulus, the human M phi showed a lucigenin-dependent CL background that was approximately 10-fold higher than in mouse M phi and decreased to low levels in resident M phi (monocyte-derived human M phi). This background was reduced by SOD to about 50%. No relevant luminol-dependent background was observed in all mouse and human M phi during culture time. b) Resident and activated mouse and human M phi could be distinguished in terms of their lucigenin-dependent CL during zymosan phagocytosis, which was persistently high in activated M phi, but decreased to comparatively low levels in resident M phi during culture time. This zymosan-elicited CL was almost completely SOD-dependent during all culture time. c) A dissociation between phagocytosis and oxygen radical release is observed: the decrease of both minolul and lucigenin-dependent CL in resident phagocytizing M phi during maturation did not correspond to a decrease of their phagocytic activity. Phagocytosis occurred at a high rate also in the absence of a relevant CL-detectable generation of oxygen radicals. The oxygen radical release, as measured by SOD-inhibitable cytochrome c reduction, paralleled CL during zymosan phagocytosis and declined with maturation of monocytes into M phi. In contrast, the zymosan-induced nitro-blue-tetrazolium reduction increased in mature resident human M phi. Thus, it seems that different metabolic pathways are utilized during phagocytosis in young and mature M phi.

Interaction between human polymorphonuclear leucocytes and Staphylococcus aureus in the presence and absence of opsonins

Phagocytosis of Staphylococcus aureus by human polymorphonuclear leucocytes (PMN) in the presence and absence of opsonins was studied with an assay which allows interaction between PMN and bacteria on a surface. The kinetics of uptake, the activity of the metabolic burst, and the degranulation during phagocytosis of opsonized and unopsonized bacteria were compared. Uptake of unopsonized S. aureus proceeded at a slower rate, but unopsonized staphylococci induced metabolic activity and degranulation in the PMN to the same extent as opsonized bacteria. Treatment of PMN with a metabolic inhibitor (2-deoxy-D-glucose) or with an inhibitor of microfilament function (cytochalasin B) totally inhibited the capacity of PMN to ingest unopsonized S. aureus, whereas uptake of opsonized bacteria was much less affected. Treatment of the PMN with pronase prevented uptake of unopsonized bacteria, but had no effect on the uptake of opsonized bacteria. Uptake was not inhibited by mannose. Recognition of S. aureus by the PMN was not dependent on the presence of the cell wall components protein A or teichoic acid. The presence of a capsule inhibited uptake.

Polymorphonuclear leukocytes: dedicated professional phagocytes

Polymorphonuclear leukocytes are termed professional phagocytes because they are specially equipped to seek and destroy invading microorganisms. Polymorphonuclear leukocytes are formed in the bone marrow and released into the circulation, where they are transported to the tissues. At sites of tissue invasion by microorganisms, humoral factors are released that induce these cells to leave the bloodstream and enter the tissues. Chemotactic substances guide polymorphonuclear leukocytes to the infecting organisms. Antibody and complement can function as opsonins and enhance the ability of polymorphonuclear leukocytes to engulf microbes. Ingested organisms are killed by oxidative or nonoxidative systems. Defects in the various aspects of polymorphonuclear leukocyte function may be found in patients with recurrent, severe, or unusual infections. Evaluation of selected patients with recurrent infections should include tests of polymorphonuclear leukocyte function.

Platelet activating factor (PAF) induces the oxidative burst in macrophages

The response of guinea pig peritoneal macrophages to platelet activating factor (1-O-octadecyl-2-acetyl-sn-glycero-3-phosphoryl-choline) was examined. In Corynebacterium parvum induced macrophages, platelet activating factor, over a wide dose range (3.8 X 10(-5) to 3.8 X 10(-9)M) triggered the oxidative burst as indicated by increased luminol-dependent chemiluminescence and hydrogen peroxide release into culture supernatants. This effect of PAF was inhibited by superoxide dismutase and catalase. Resident macrophages exhibited only slight respiratory activity in response to platelet activating factor which could be increased by adding 1% gelatine to the medium. Activation of macrophages is a new biological effect exerted by platelet activating factor. In immuno-inflammatory reactions, cells capable of generating platelet activating factor may come into close contact with macrophages and by liberating this mediator cause them to release highly toxic oxygen species known to be microbicidal and cytocidal and able to produce vascular endothelial injury. Our findings lend further support to the view that platelet activating factor is a potent and rapid activator of physiological defence mechanisms.

Bacteria and zymosan opsonized with histone, dextran sulfate, and polyanetholesulfonate trigger intense chemiluminescence in human blood leukocytes and platelets and in mouse macrophages: modulation by metabolic inhibitors in relation to leukocyte-bacteria interactions in inflammatory sites

Human blood leukocytes and platelets and mouse peritoneal macrophages emit very rapid and very intense Luminol-dependent chemiluminescence (CL) signals when treated with streptococci, staphylococci, or with zymosan, which have been preopsonized with arginine-rich histone, dextran sulfate or polyanetholesulfonate (liquoid). Liquoid alone at 10-30 micrograms/2 X 10(5) leukocytes also triggers intense CL responses in the absence of a carrier. Strong CL can also be triggered, and at the same levels, when the various polyelectrolytes are simply mixed with the bacteria or zymosan and added to the leukocyte suspensions. The CL responses induced by the polyelectrolyte-bacteria complexes greatly exceed those triggered in leukocytes by antibody-complement-coated particles. Liquoid also shows a unique property of markedly augmenting CL signals which have already been induced by other ligand-coated bacteria or zymosan particles. Streptococci and staphylococci were found to be much superior to zymosan, Gram-positive bacilli, or E. coli as carriers for the various polyelectrolytes in the CL reaction. Neither protamine sulfate, lysozyme, myeloperoxidase, crystalline ribonuclease (all cationic in nature), chondroitin sulfate, heparin, nor alginate sulfate acted as ligands for triggering CL, when used to opsonize bacteria or zymosan. The induction of CL in blood leukocytes by the various ligand-coated bacteria is markedly inhibited by azide, KCN catalase, aminotriazole, and EDTA, agents known to inhibit the production of oxygen radicals following stimulation of leukocytes by opsonized bacteria. Two children diagnosed for chronic granulomatous diseases (CGD) of childhood and an apparently healthy sister of one of the male patients completely failed to respond with CL either to the polyelectrolyte-bacteria complexes, liquoid or antibody-coated bacteria and zymosan. It is proposed that liquoid be employed for the rapid screening of defects in certain oxygen-dependent metabolic processes in both PMNs and macrophages. It is also suggested that polyelectrolytes like the ones described in this study may markedly enhance the bactericidal properties of leukocytes and macrophages towards both extracellular and intracellular microorganisms and may perhaps also augment the tumoricidal effects of activated macrophages.

Non-specific resistance of mice to bacteria, induced by an acellular extract from Pseudomonas aeruginosa

Antibacterial activity of an acellular extract from Pseudomonas aeruginosa (AEP) was assessed in mice infected with bacteria including extracellular and intracellular bacteria. It was shown that AEP strongly increased resistance of mice to bacterial infections. The protective effect was maximal between days 2 and 5 after inoculation of AEP, and subcutaneous inoculation was most efficient. The ED90 of AEP was about 30 micrograms per mouse (i.e. about 10 times less than that of Corynebacterium parvum). AEP caused an increased in Listeria monocytogenes destruction in the spleen and liver. AEP-treated mice exhibited an early recruitment of phagocytes after bacterial challenge in the peritoneal cavity. Furthermore, phagocytosis and O2-dependent bactericidal systems were studied by measuring the chemiluminescence response from macrophages under exposure to L. monocytogenes and Staphylococcus aureus: the response was earlier and higher from AEP-stimulated macrophages than from controls. It was concluded that AEP induces an early recruitment of phagocytes and increases their bactericidal activity.