Role of nuclear lamins in nuclear segmentation of human neutrophils

Nuclear breakdown leading to the formation of apoptotic bodies has been postulated to involve degradation of nuclear structural proteins, such as lamins A/C and B. Although nuclear segmentation occurs during the maturation of polymorphonuclear leukocytes (neutrophils), its mechanism is not known. We found that human neutrophils have lamin B but lack lamins A/C while mononuclear cells possess all three types of lamin as assessed by immunoblotting. Differentiation of human promyelocytic HL-60 cells into neutrophil-like cells was also accompanied by the down-regulation of lamins A/C but not of lamin B. Moreover, when compared with normal cells, neutrophils with the Pelger-Hu?t anomaly of nuclear hyposegmentation exhibited significantly lower activity of caspase-6, a lamin A/C-cleaving enzyme. Differentiated HL-60 cells showed higher activity of caspase-6 than that of untreated cells. These observations allow us to speculate that remodeling of nuclear lamins might underlie the mechanism for nuclear segmentation of neutrophils.     

Characteristics of cardiac rhythm and the peroxidase activity of blood in patients with ischemic heart disease treated by hyperbaric oxygenation]

The myeloperoxidase of peripheral blood neutrophils revealed by the cytochemical method was investigated in a group of patients with ischemic heart disease (24 men, mean age--51) treated with HBO (10 sessions, under 1.5-1.7 ata, for 60 min) prior to and after each HBO session. The ECG monitoring was performed during these sessions as well. A correlation analysis of the peroxidase index (mean enzyme content in 100 cells), total peroxidase activity and tension index (obtained by computer analysis of cardiac rhythm changes) was carried out in that group of patients. A close correlation was found between the total peroxidase activity and tension index.     

Cytogenetic findings in a prospective series of patients with DiGeorge anomaly.

High-resolution cytogenetics analysis of peripheral blood lymphocytes was done prospectively on 27 of 28 patients with features of DiGeorge anomaly. Twenty-two patients (81%) had normal chromosome studies with no detectable deletion in chromosome 22. Five patients (18%) had demonstrable chromosome abnormalities. Three patients had monosomy 22q11, one due to a 4q;22q translocation, one due to a 20q;22q translocation, and one due to an interstitial deletion of 22q11. One patient had monosomy 10p13, and one patient had monosomy 18q21.33, although the latter had subsequent resolution of T-cell defects. These findings are consistent with the heterogeneity of DiGeorge anomaly but confirm the association with monosomy 22q11 in some cases. However, monosomy 10p13 may also lead to this phenotype. Because of these associated chromosome findings, cytogenetic analyses should be done on patients with suspected DiGeorge anomaly. This is particularly important since many of the abnormalities involving chromosome 22 are translocations that can be familial with a higher recurrence risk. Since only one subtle, interstitial deletion of chromosome 22 was observed, it is not clear whether high-resolution cytogenetic analysis is cost beneficial for all such patients.     

Subpopulations of neutrophils with increased oxidative product formation in blood of patients with infection

Stimulated human polymorphonuclear leukocytes (PMNL) have a marked increase in oxidative metabolism, producing reduced oxygen species (e.g., H2O2) that mediate bacterial killing. Previously, quantitation of metabolic responses of PMNL from patients with acute infections employed assays that measure mean activity of the entire PMNL population; such studies reported a modest and highly variable increase in oxidative metabolic responses of such "toxic" PMNL compared with normal cells. To assess metabolic capability of PMNL from 51 patients with acute bacterial infection, we employed a quantitative flow cytometric assay of H2O2-dependent oxidative product formation, the intracellular oxidation of 2',7'-dichlorofluorescin (DCFH). After stimulation by phorbol myristate acetate, the PMNL of patients demonstrated an increase in mean DCFH oxidation (315 +/- 14 and 180 +/- 4.5 amol/cell, patients and controls). Hexose monophosphate shunt activation was similarly increased in stimulated PMNL from bacteremic patients. These data are comparable with previous studies of mean metabolic activities of toxic PMNL. However, these mean values underestimate the quantitative responses of the hyperresponsive ("primed") PMNL within a mixture of normal and primed PMNL in the patients' blood. The flow cytometric assay demonstrated that the PMNL of the patients were composed of two populations. One population of PMNL had normal oxidative responses; the other "primed" population had up to 4.6 times the oxidative product formation of normal cells. Similar priming of circulating PMNL was caused by infection with gram-positive or gram-negative staining bacteria or by Candida species. The proportion and oxidative ability of the primed PMNL occurred independently of the number of juvenile neutrophil forms and independently of "toxic" morphologic changes of Wright's-stained PMNL. On the average, 40% of the PMNL of patients were primed, but the size of the primed PMNL population varied widely between patients (range 0 to 80%). This variable subpopulation may explain the variability of mean responsiveness of the PMNL of patients reported previously. Moreover, the marked increase in oxidative metabolic capability of the primed PMNL may be a significant component of the host response to acute infection. It could also contribute to the damage to host tissues such as pulmonary vascular endothelium during bacteremia.     

Cytochemical and ultracytochemical studies of peroxidase activity in rabbit blood granulocytes under hydrocortisone effect

Cytochemically peroxidase activity has been examined on the light optical and ultrastructural levels in blood granulocytes of the rabbits after a single (5 mg/kg) and multiple (1 and 5 mg/kg every 24 hrs during 4 weeks) administrations of hydrocortisone. Under electron microscope peroxidase activity was detected in the blood of intact rabbits into typical primary granules (TPG) and small polymorphic granules (SPG) of neutrophils as well as into specific granules of basophils sometimes in perinuclear space and GER channels. 6 h after hydrocortisone injection peroxidase activity in neutrophils increased, the reaction product in both kinds of cytoplasmic granules was electron denser than in the controls. After multiple hydrocortisone (1 mg/kg) administrations peroxidase general activity in granulocytes has not considerably changed, but the number of TPGs and SPGs was decreased in neutrophils. Multiple administrations of a higher dose of hydrocortisone (5 mg/kg) have induced peroxidase activity decreasing in neutrophils and a decrease in the number and electron density of TPGs and SPGs in them. In basophils there was a significant accumulation of the reaction product of high electron density in perinuclear space, in specific granules and GER channels. The conclusions has been drawn that a short-term raising of hydrocortisone level stimulates and prolonged hypercorticism inhibits peroxidase activity in neutrophils and, consequently, their function.     

Sulforaphane Restores Cellular Glutathione Levels and Reduces Chronic Periodontitis Neutrophil Hyperactivity In Vitro

The production of high levels of reactive oxygen species by neutrophils is associated with the local and systemic destructive phenotype found in the chronic inflammatory disease periodontitis. In the present study, we investigated the ability of sulforaphane (SFN) to restore cellular glutathione levels and reduce the hyperactivity of circulating neutrophils associated with chronic periodontitis. Using differentiated HL60 cells as a neutrophil model, here we show that generation of extracellular O₂ ^{. -} by the nicotinamide adenine dinucleotide (NADPH) oxidase complex is increased by intracellular glutathione depletion. This may be attributed to the upregulation of thiol regulated acid sphingomyelinase driven lipid raft formation. Intracellular glutathione was also lower in primary neutrophils from periodontitis patients and, consistent with our previous findings, patients neutrophils were hyper-reactive to stimuli. The activity of nuclear factor erythroid-2-related factor 2 (Nrf2), a master regulator of the antioxidant response, is impaired in circulating neutrophils from chronic periodontitis patients. Although patients’ neutrophils exhibit a low reduced glutathione (GSH)/oxidised glutathione (GSSG) ratio and a higher total Nrf2 level, the DNA-binding activity of nuclear Nrf2 remained unchanged relative to healthy controls and had reduced expression of glutamate cysteine ligase catalytic (GCLC), and modifier (GCLM) subunit mRNAs, compared to periodontally healthy subjects neutrophils. Pre-treatment with SFN increased expression of GCLC and GCM, improved intracellular GSH/GSSG ratios and reduced agonist-activated extracellular O₂ ^{. -} production in both dHL60 and primary neutrophils from patients with periodontitis and controls. These findings suggest that a deficiency in Nrf2-dependent pathways may underpin susceptibility to hyper-reactivity in circulating primary neutrophils during chronic periodontitis.     

Inhibition by BN 52021 (ginkgolide B) of the binding of [3H]-platelet-activating factor to human neutrophil granulocytes

The inhibitory effect of BN 52021, a specific antagonist of platelet-activating factor (PAF) on PAF-induced activation of human polymorphonuclear granulocytes (PMNL) and on the binding of [3H]-PAF to neutrophils were examined. BN 52021 over the range of 10(-9)-10(-4) M inhibited PAF-induced degranulation and superoxide production of PMNLs in a dose-dependent manner with Kd values of 0.6 +/- 0.1 x 10(-6) M and 0.4 +/- 0.1 x 10(-6) M, respectively. BN 52021 (up to 1 mM) did not show any agonistic activity and it did not affect neutrophil responses to N-formyl-methionyl-leucyl-phenylalanine or leukotriene B4. The Ki value of BN 52021 for the specific binding of [3H]-PAF to neutrophils was 1.3 +/- 0.5 x 10(-6) M versus a Ki of 1.1 +/- 0.3 x 10(-7) M for PAF itself. BN 52021 did not affect metabolism of PAF by PMNL. These studies indicate that BN 52021 inhibits neutrophil responses to PAF by inhibiting binding of PAF to its specific PMNL receptor.     

Extract of Perilla frutescens enriched for rosmarinic acid, a polyphenolic phytochemical, inhibits seasonal allergic rhinoconjunctivitis in humans

Extract of Perilla frutescens enriched for rosmarinic acid, a polyphenolic phytochemical, suppresses allergic immunoglobulin responses and inflammation caused by polymorphonuclear leukocytes (PMNL) in mice. However, few placebo-controlled clinical trials have examined the efficacy and safety of polyphenolic phytochemicals for treatment of allergic inflammatory diseases in humans. The present study determined whether oral supplementation with rosmarinic acid is an effective intervention for patients with seasonal allergic rhinoconjunctivitis (SAR). In this 21-day, randomized, double-blind, age-matched, placebo-controlled parallel group study, patients with mild SAR were treated daily with extract of Perilla frutescens enriched for rosmarinic acid (200 mg [n=10] or 50 mg [n=9]) or placebo (n=10). Patients recorded symptoms daily in a diary. Profiles of infiltrating cells and concentrations of eotaxin, IL-1beta, IL-8, and histamine were measured in nasal lavage fluid. Serum IgE concentrations and routine blood tests were also examined. As compared with placebo supplementation, supplementation with extract of Perilla frutescens enriched for rosmarinic acid resulted in a significant increase in responder rates for itchy nose, watery eyes, itchy eyes, and total symptoms (P<0.05). Active treatment significantly decreased the numbers of neutrophils and eosinophils in nasal lavage fluid (P<0.05 vs. placebo). Patients reported no adverse events, and no significant abnormalities were detected in routine blood tests. In conclusion, extract of Perilla frutescens enriched for rosmarinic acid can be an effective intervention for mild SAR at least partly through inhibition of PMNL infiltration into the nostrils. Use of this alternative treatment for SAR might reduce treatment costs for allergic diseases.     

Polycythemia vera: electron microscopy of the bone marrow in 10 non-treated patients. A thin section and freeze-fracture study.

Electron microscopy (thin sections and freeze-fracture replicas) was performed on the bone marrow of ten patients with Polycythemia vera prior to any treatment. In addition to a hyperplasia of all three cell lineages and the sinuses, atypias were observed in the maturing erythroblasts. These aberrations of normal development consisted mainly of deep invaginations of the nuclear envelope in proerythroblasts and conspicuous nuclear clefts in erythro- and normoblasts. In comparison with similar changes in dyserythropoietic and aplastic anemia as well as leukemia these alterations are discussed in connection with disturbances of DNA synthesis. Further atypias involved megakaryopoiesis which displayed microforms probably as an evidence for maturation arrest. These ultrastructural abnormalities and their morphological features of a neoplastic proliferation of all three cell lineages in Polycythemia vera are in good agreement with the new concept of a transformation of a pluripotent stem cell with clonal character.     

Antimicrobial immunity in patients with acute epiglottitis

Fifty-three patients with catarrhal epiglottitis and 31 patients with epiglottic abscess aged 16-60 years were examined. It was determined that development of epiglottitis is tightly related to abnormalities in reactivity of phagocytic and humoral arms of immunity. Decreased affinity of produced antibodies, opsonizing properties of serum as well as phagocytic and biocide activity of neutrophils were revealed in patients. In patients with catarrhal and necrotic epiglottitis similar abnormalities of immunoreactivity were observed although in patientswith necrotic epiglottitis they were more pronounced.     

Ultrastructural and histological study of degenerative changes in the antennal glands, hepatopancreas, and midgut of grass shrimp exposed to two dithiocarbamate biocides

The histological and ultrastructural alterations observed in the antennal glands, hepatopancreas, and midgut of grass shrimp exposed to either a 50% potassium dimethyldithiocarbamate biocide (Busan-85; 5–60 ppb) for 14 days, or to a different biocide, composed of 15% sodium dimethyldithiocarbamate and 15% disodium ethylene bisdithiocarbamate (Aquatreat DNM-30), for 3–4 days (60–140 ppb) and 28–35 days (40–120 ppb), were compared and contrasted with the normal morphological features in control shrimp. Only those experimental shrimp that exhibited various degrees of branchial abnormality were examined. Although the alterations in Busan-exposed shrimp were generally more pronounced, the antennal glands of 32 out of 36 experimental shrimp exhibited abnormalities that were manifested primarily as increased secretory activity by the labyrinth cells. In dithiocarbamate-exposed shrimp with “black gills”, the labyrinth epithelium exhibited moderate nuclear hypertrophy, apparent cell sloughing, intense secretory activity, and occasional melanized lesions; alterations in the antennal gland coelomosac included nuclear pyknosis, a general deterioration of podocyte organization, and an unusual increase in hemolymph density adjacent to affected tissues. Although there was an apparent increase in mitotic activity in the hepatopancreatic tubules of shrimp exposed to Aquatreat for 28–35 days, degenerative changes were most frequent and extensive in the hepatopancreas and midgut of dithiocarbamate-exposed shrimp with “black gills”. These observed changes included the diminution of the basal midgut and hepatopancreatic tubular system, moderate midgut hypertrophy, pronounced activity by the hepatopancreatic fixed phagocytes, development of mitochondrial inclusions and megamitochondria, loss of cytoplasmic density, hepatopancreatic nuclear pyknosis, and irreversible degeneration of hepatopancreatic tubule apices. This study suggests that some of the observed abnormal/pathological changes are the indirect consequence of branchial degeneration. A number of possible defensive reactions to dithiocarbamate poisoning, including heterostasis, phagocytosis, encapsulation, and the possible participation of reserve inclusion cells are proposed.     

The influence of age and sex on phagocyte chemiluminescence

The process of ageing is associated with increased susceptibility to infection. Phagocytes form the primary defence mechanism against infecting microorganisms, but the influence of ageing on phagocyte function remains controversial. In this study we have applied a microtitre plate phagocyte chemiluminescence (CL) assay suitable for clinical use to compare phagocyte oxidative metabolism in younger healthy subjects (age 20–60 years) and healthy older (60–70 years) subjects. Polymorphonuclear leukocytes (PMNL) and monocytes were stimulated using phorbol myristate acetate (PMA), serum opsonized zymosan (SOZ), and non-opsonized zymosan (ZYM) in the presence of both lucigenin and luminol. Monocytes showed a higher luminolenhanced CL response to PMA in males compared with females in the younger age group. No PMNL differences were observed between the sexes. Although no difference were found in relation to age when cells were stimulated with PMA and SOZ, significantly lower background (unstimulated) CL was obtained from PMNL with luminol. PMNL luminol-enhanced CL responses were also lower in response to ZYM. The findings suggest a reduced response of PMNL from older subjects to minimal stimulation. This could be related to abnormalities in the triggering of the respiratory burst or myeloperoxidase release due to ageing. The influence of age and sex should be taken into account in clinical studies of phagocyte CL.     

The dynamics of the T-lymphocyte subpopulations and the peroxidase activity of the neutrophils in children immunized with a live mumps vaccine

The amount of T-helpers and T-suppressors and the T-helper/T-suppressor ratio were determined in 30 practically healthy children aged 1.5-2 years, immunized with live parotitis vaccine prepared from strain -3. One immunization dose of the vaccine contained 7,950 HADU50. In all children peroxidase activity in the cytoplasm of neutrophils was studied. This investigation revealed that in all examined children the formation of immune response to immunization with live parotitis vaccine was accompanied by the development of an imbalance of immunoregulatory T-cell subpopulations and by functional changes in neutrophils, characterized by the inhibition of peroxidase activity. The changes revealed in this study were most pronounced in children with a high level of antibody formation.     

Annexin 1 localisation in tissue eosinophils as detected by electron microscopy

BACKGROUND: Human and rodent leukocytes express high levels of the glucocorticoid-inducible protein annexin 1 (ANXA1) (previously referred to as lipocortin 1). Neutrophils and monocytes have abundant ANXA1 levels. AIM: We have investigated, for the first time, ANXA1 ultrastructural expression in rat eosinophils and compared it with that of extravasated neutrophils. The effect of inflammation (carrageenin peritonitis) was also monitored. METHODS: Electron microscopy was used to define the sub-cellular localisation of ANXA1 in rat eosinophils and neutrophils extravasated in the mesenteric tissue. A pair of antibodies raised against the ANXA1 N-terminus (i.e. able to recognise intact ANXA1, termed LCPS1) or the whole protein (termed LCS3) was used to perform the ultrastructural analysis. RESULTS: The majority of ANXA1 was localised in the eosinophil cytosol (approximately 60%) and nucleus (30-40%), whereas a small percentage was found on the plasma membrane (< 10%). Within the cytosol, the protein was equally distributed in the matrix and in the granules, including those containing the typical crystalloid. The two anti-ANXA1 antibodies gave similar results, with the exception that LCPS1 gave a lower degree of immunoreactivity in the plasma membrane. Inflammation (i.e. carrageenin injection) produced a modest increase in eosinophil-associated ANXA1 reactivity (significant only in the cytoplasm compartment). Extravasated neutrophils, used for comparative purposes, displayed a much higher degree of immunoreactivity for the protein. CONCLUSION: We describe for the first time ANXA1 distribution in rat eosinophil by ultrastructural analysis, and report a different protein mobilisation from extravasated neutrophils, at least in this acute model of peritonitis.     

Selenium, glutathione and glutathione peroxidases in blood of patients with chronic liver diseases

Disturbances in the antioxidant system could play a role in pathogenesis of chronic liver disease. The aim of our study was to evaluate the levels/activities of antioxidants in blood of patients with chronic liver disease. We estimated selenium and glutathione concentrations and glutathione peroxidase activities in blood of 59 patients with chronic hepatitis B or C virus infection (group 1) and 64 patients with alcoholic, autoimmune or cryptogenic chronic liver disease (group 2). The results were compared with 50 healthy controls. Whole blood and plasma selenium and red cell glutathione concentrations were significantly lower in the patients compared with the controls. Red cell glutathione peroxidase activity was slightly reduced in both subgroups of group 1 and in group 2 with normal alanine aminotransferase values. Plasma glutathione peroxidase activity was slightly but significantly higher in patients with elevated aminotransferase values. The findings suggest that disturbances in antioxidant parameters in blood of patients with chronic liver disease may be the cause of the peroxidative damage of cells.     

Phagocytosis and peroxidase activity in neutrophils from peripheral blood of patients with malignant tumours of lung, stomach and large intestine

The phagocytic activity as revealed by latex ingestion and cytochemically demonstrated peroxidase activity of neutrophils from peripheral blood was investigated in 26 patients with pulmonary cancer, 22 patients with gastric cancer and 8 patients with tumours of large intestine and compared with results obtained in 40 healthy individuals. Statistically significant differences were found in case of both parameters between patients with pulmonary cancer and those with tumours of large intestine. The lowered phagocytic activity of neutrophils was accompanied by an enhanced peroxidase activity and vice versa. No statistically significant differences were observed, however, between the investigated groups of patients with cancer and the control group.     

Ultrastructural examination of the host inflammatory response within gills of netpen reared chinook salmon (Oncorhynchus tshawytscha) with Microsporidial Gill Disease

The sequence of host changes following the rupture of spore-laden xenomas of the microsporidian Loma salmonae during Microsporidial Gill Disease of Salmon was deduced from ultrastructural examination of the gills of naturally infected, moribund, chinook salmon from a commercial aquaculture site. The gills contained many stages of parasite development suggesting fish were chronically exposed to the parasite. Intact xenomas were generally found beneath the endothelium in arteries and arterioles and were encapsulated by a layer of collagen containing fibroblasts sometimes joined by desmosomes. Xenoma dissolution was characterized by neutrophil infiltration and loss of the xenoma plasma membrane and encapsulation. The inflammatory responses associated with ruptured xenomas ranged from acute lesions, denoted by a marked neutrophil infiltration and vascular thrombosis, to chronic lesions with a macrophage-rich infiltrate variously accompanied by neovascularization and vascular remodelling. Dendritic-like cells and plasma cells were characteristic throughout. Basement membrane damage of the primary filament epithelium and subsequent transepithelial expulsion of spores were associated with severe inflammation. An unusual previously undescribed multifocal change, in which epithelial cells invaded deeply beyond the normal boundaries of the basement membrane, affected areas of gill filament epithelium with basement membrane damage. Some neutrophils that contained L. salmonae spores, or spore polar tube, displayed morphological changes that included irregular cell shape, cytoplasmic darkening associated with an abundance of free ribosomes, lysis of neighbouring cells, and type II nuclear clefts. Fusion of apparently intact neutrophils occurred in other areas of the lesion, where close contacts between neighbouring cells were established and in some areas plasma membrane fusion occurred. Closely associated neutrophils with intact plasma membranes were observed to contain type II nuclear clefts, abundant granules and rough endoplasmic reticulum. Other neutrophils in the lesion displayed type I nuclear pockets, which is suspected to be an early stage of apoptosis.     

Photoaffinity labeling of the N-formyl peptide receptor of human polymorphonuclear leukocytes

Quantitative analysis of ligand-occupied receptor interactions with elements of the cytoskeleton and with intracellular compartments requires a sensitive and simple method of identifying the receptor-ligand complex in living cells. Toward this goal, we have prepared a photoactivatable arylazide derivative of the chemotactic peptide N-formyl-Nle-Leu-Phe-Nle-Tyr-Lys, which can be radiolabeled to high specific activity with 125I. This derivative was biologically active as judged by its ability to elicit superoxide anion production by human PMNL at nanomolar concentrations (ED50 approximately 0.7 nM). When incubated at 0 degree C with whole PMNL, radioactive ligand became specifically and saturably associated with a 60-70,000-dalton species (as assessed by SDS-PAGE) after exposure to UV light. Addition of 10-100-fold excess of unlabeled parent or unlabeled azidopeptide derivative completely blocked uptake into this species. Approximately 20-40% of the available surface receptor-binding sites were covalently labeled under these conditions. Subcellular fractionation of the labeled cells on sucrose gradients after homogenization showed that the labeled species was primarily associated with plasma membrane-rich fractions. The labeled receptor could be completely solubilized with Triton X-100 in a form which eluted as a single species with a Stoke's radius of less than 50 A on Sepharose 4B columns. In addition, the solubilized receptor-ligand complex bound specifically to wheat germ agglutinin, indicating that it is probably a glycoprotein. The ability to label the receptor in living PMNL with a high efficiency should facilitate the study of receptor dynamics and receptor physiochemical properties in this system.     

Leukotriene production and inactivation by normal, chronic granulomatous disease and myeloperoxidase-deficient neutrophils

Appropriately stimulated neutrophils release peroxidase and undergo a respiratory burst to form hydrogen peroxide (H2O2) and hydroxyl radicals (OH). We report here that both the myeloperoxidase-H2O2-halide system and OH released in this way can degrade the leukotrienes (LT) formed by neutrophils. More LTB4 and LTC4 were recovered from the supernatants of chronic granulomatous disease neutrophils (which are unable to respond to stimulation with a respiratory burst) than from normal or myeloperoxidase-deficient neutrophils when stimulated with the calcium ionophore A23187. When radiolabeled LTC4 was added, 72% of the LTC4 was recovered from the chronic granulomatous disease cells in contrast to 0% from the myeloperoxidase-deficient and normal cells. Inhibitor studies using catalase, superoxide dismutase, azide, mannitol, or ethanol suggested that LTC4 degradation was mediated primarily by the myeloperoxidase system in normal cells and by OH in myeloperoxidase-deficient cells. LTC4 degradation by the cell-free myeloperoxidase-H2O2-halide system and the OH -generating acetaldehyde-xanthine oxidase-Fe2+ system had inhibitor profiles comparable to normal and myeloperoxidase-deficient neutrophils, respectively. LTC4 degradation products formed by the stimulated neutrophils and model systems included the 5-(S), 12-(R)- and 5-(S), 12-(S)-6-trans-isomers of LTB4. Thus phagocytes may modulate LT activity in inflammatory sites by the inactivation of these potent biologic mediators by at least two oxidative mechanisms.     

Analysis of human neutrophil granule protein composition in chronic myeloid leukaemia by immuno-electron microscopy

Summary In this study immuno-electron microscopy was used to assay, semi-quantitatively, the granule contents of elastase, lactoferrin, lysozyme and myeloperoxidase in human peripheral blood neutrophils from 13 chronic myeloid leukaemia patients in the chronic phase of the disease and from normal non-smoking donors. The fixation conditions that adequately preserved the antibody binding capacities of these antigens and reasonably preserved the ultrastructure of the neutrophils were selected by light-microscopic immunoperoxidase cytochemistry on cytospin smears. Immunogold cytochemistry on LR White resin sections localised elastase and myeloperoxidase to the primary granules, lactoferrin to the secondary granules and lysozyme to both types of granule. When applicable, peroxidase cytochemistry was combined with immunogold staining making it easier to distinguish the primary from the secondary granules. A comparison of the immunolabelling density values obtained for the leukaemic and normal states revealed no significant abnormalities in the immunoreactivity patterns for any of these neutrophil granule antigens in the leukaemic patients. All 13 patients gave normal immunostaining reactivities for these neutrophil granule proteins. Consequently the distribution patterns of these proteins, as shown in this study, cannot be used as indices in distinguishing chronic myeloid leukaemic neutrophils from normal neutrophils.