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Biomedical subjects

G J Gleich

Publications and source records attributed to G J Gleich.

At least 19 recordsLinked to original sources

Eosinophil-derived neurotoxin and human liver ribonuclease. Identity of structure and linkage of neurotoxicity to nuclease activity.

Eosinophil-derived neurotoxin (EDN) and human liver RNase were found to be indistinguishable from each other but distinct from the pancreatic ribonucleases in their nucleolytic activity on polynucleotides or small defined substrates. Antibodies to EDN and liver RNase showed identical cross-reactivities in assays of nuclease inhibition and in a radioimmunoassay. In each instance, EDN and liver RNase were easily distinguished from bovine or human pancreatic RNase. When injected intrathecally into rabbits, 5-10 micrograms of EDN or liver RNase each was neurotoxic as judged by induction of the Gordon phenomenon. Human pancreatic RNase was less neurotoxic, and up to 20-fold higher levels of bovine pancreatic RNase showed no effect. Treatment of EDN, liver RNase, and eosinophil cationic protein with iodoacetic acid at pH 5.5 resulted in inactivation of their RNase activity and also destroyed their neurotoxicity. EDN conformation was not greatly affected by iodoacetate treatment since interaction of the modified protein with antibodies was only slightly altered. We conclude that RNase activity is necessary but not sufficient to induce neurotoxic action.

Amino Acid Sequence

Release of granule proteins from eosinophils cultured with IL-5.

Eosinophils isolated from normal individuals were cultured in the presence of human rIL-5 (hrIL-5) for up to 14 days, and the effects of this exposure were determined. First, the hrIL-5-cultured eosinophils were activated and degranulated more readily than freshly isolated eosinophils. For example, eosinophils cultured for 7 days with hrIL-5 released 30 and 10% of granule eosinophil-derived neurotoxin (EDN) when exposed to Sepharose 4B beads coupled to secretory IgA and IgG, respectively, whereas freshly isolated eosinophils released only 19 and 4%, respectively, of their EDN in response to the same stimuli. Degranulation of hrIL-5-cultured eosinophils was not augmented by further exposure to hrIL-5, whereas degranulation of freshly isolated cells to secretory IgA and IgG beads was increased by exposure to hrIL-5. Second, eosinophils cultured with hrIL-5 had prolonged viability in vitro. For example, after four days of culture with 50 U/ml of hrIL-5, 86% of eosinophils were viable compared to 12% in medium alone. Third, hrIL-5-cultured eosinophils became hypodense, and electron microscopy showed that they contained granules with core and matrix lucency and with evidence of granule fusion. Fourth, hrIL-5-cultured eosinophils spontaneously lost 30 to 60% of their EDN, eosinophil cationic protein, and eosinophil peroxidase and about 50% of their eosinophil granule major basic protein content compared to freshly isolated eosinophils, and all four of the granule proteins were released into the culture medium. Fifth, detailed studies of eosinophils cultured in hrIL-5 showed that 89 +/- 10% of the starting quantity of EDN could be recovered at 7 days. Whereas 99 +/- 1% of the EDN at day 0 was cell associated, by 7 days 60 +/- 9% was in the cell supernatants. Thus, hrIL-5 activates eosinophils, increases their viability, decreases their density, and their content of granule proteins and causes release of the granule proteins into culture fluids. The striking loss of granule proteins during culture with hrIL-5 may be an important mechanism for deposition of these cationic toxins in various diseases where IL-5 plays a role.

Blood Proteins

Eosinophil granule cationic proteins regulate complement. I. Activity on the alternative pathway.

Eosinophil granules contain several cationic proteins that mediate tissue damage in allergic disease. The present study examined the capacity and mechanisms by which these cationic proteins regulate activity of the alternative pathway of C. Eosinophil peroxidase and eosinophil cationic protein inhibited formation of cell-bound alternative pathway C3 convertase, causing 50% inhibition of lysis at about 0.19 and 0.75 microgram/10(7) cellular intermediates, respectively. Major basic protein inhibited alternative pathway C3 activity by only 19% at 1.5 micrograms/10(7) cellular intermediates. Eosinophil-derived neurotoxin had no activity on the alternative pathway. The eosinophil granule proteins were examined for the mechanism by which they inhibited alternative pathway activity. Eosinophil peroxidase and major basic protein inhibited fluid phase factor B consumption in a reaction mixture that also contained factors D and C3b, eosinophil-derived neurotoxin had no activity on factor B consumption, and eosinophil cationic protein consumed factor B in the absence of C3b and factor D. Both eosinophil cationic protein and eosinophil peroxidase enhanced the decay of preformed alternative pathway convertase. Lysis of EAC4b,3b cellular intermediates formed to contain a low surface amount of C3b was more inhibited than was lysis of cells formed with a standard amount of C3b on the surface. This suggests that these eosinophil proteins acted predominantly on C3b to regulate alternative pathway activity. We also found that none of the eosinophil granule cationic proteins had any effect on later events after the formation of the C3 convertase. We conclude that although eosinophil-derived neurotoxin (isoelectric pH value (pI) = 8.9) does not regulate alternative pathway activity, the more highly charged eosinophil granule cationic proteins--major basic protein (pI = 10.9), eosinophil cationic protein (pI = 10.8), and eosinophil peroxidase (pI = 10.8)--do share the capacity to regulate C activity and may exert this activity in vivo.

Blood Proteins

Repeated coronary artery spasm in a young woman with the eosinophilia-myalgia syndrome.

We report a case of repeated coronary artery spasm with myocardial injury in a 37-year-old woman with the eosinophilia-myalgia syndrome. This patient did not have a medical history of cardiac-related illness or risk factors for coronary artery disease. The presence of eosinophil granule major basic protein in otherwise normal-appearing myocardial tissue, along with normal plasma levels of tryptophan metabolites, suggests that the mechanism of vasospasm in this patient might involve toxic eosinophil proteins or focal myocardial lesions, but not the production of excess tryptophan metabolites.

Adult

Elevated serum levels of interleukin-5 in patients with the syndrome of episodic angioedema and eosinophilia.

The syndrome of episodic angioedema and eosinophilia is characterized by cyclic edema, marked peripheral blood eosinophilia, and eosinophil degranulation in the dermis. Using a sensitive immunoenzymetric method, we measured serum interleukin (IL)-5 levels in four patients with this syndrome. We also determined the percentage of activated T cells in the peripheral blood of a new patient before and during an attack. In the patient presented, IL-5 levels peaked several days before maximal eosinophilia and then declined. This patient's lymphocytes showed an increased percentage, 28% (normal 2% to 3%), of activated T cells staining for both CD3 and HLA-DR 10 days before maximal eosinophilia, but no increase at the time of peak eosinophilia. In serum from three previously reported cases, elevated serum IL-5 levels were found during attacks. After glucocorticoid administration, IL-5 levels became undetectable in three of the four patients. Production of IL-5 is likely an important determinant of the pathophysiology of this syndrome.

Adult

Granule-associated flavin adenine dinucleotide (FAD) is responsible for eosinophil autofluorescence.

Unstained human eosinophils exhibit marked autofluorescence in comparison to other leukocytes due to a granule-associated fluorescent substance. Fluorescence spectroscopy of granule extracts reveals excitation maxima at approximately 380 and approximately 450 nm with a single emission at approximately 520, characteristic of flavins. The fluorescent material from eosinophil granule extracts was characterized by fluorescence, high-performance liquid chromatographic, and enzymatic analyses. First, acidification to pH 2.6 resulted in increased fluorescence, indicative of flavin adenine dinucleotide (FAD). Second, because flavin mononucleotide (FMN) and riboflavin cannot be distinguished by acidification, high-performance liquid chromatography was performed and revealed a predominance of FAD and smaller amounts (< 15%) of both FMN and riboflavin. Third, the presence of FAD was clearly demonstrated by reconstitution of the activity of D-amino acid oxidase, a FAD-dependent enzyme, when granule extracts were added to the apoenzyme. Thus, we have identified FAD as the predominant fluorophore in eosinophil granules. The small amounts of FMN and riboflavin detected may result from the hydrolysis of FAD under the acidic conditions of granule extraction. Because fluorescent material is deposited onto target cells by eosinophils, it is possible that granule-associated flavoproteins may act as a source of hydrogen peroxide and/or superoxide, which, in conjunction with eosinophil peroxidase, could yield potent cytotoxic agents.

Chromatography, High Pressure Liquid

Eosinophil granule proteins in peripheral blood granulocytes.

Eosinophils contain four principal cationic proteins, major basic protein (MBP), eosinophil-derived neurotoxin (EDN), eosinophil cationic protein (ECP), and eosinophil peroxidase (EPO). To determine the quantities of these proteins in granulocytes and whether they are specific to eosinophils, their concentrations in lysates of human granulocytes were measured using specific radioimmunoassays. The effect of different methods for eosinophil lysis on the recovery of the proteins was also studied. Maximal recovery occurred at pH 2 for MBP and pH 5.6 for the other granule proteins. The proteins cosedimented with eosinophils and their concentrations (mean +/- SEM) in ng/10(6) eosinophils (and in nM/10(6) eosinophils) were: MBP, 8,982 +/- 611 (641.6); EDN, 3,283 +/- 116 (178.4); ECP, 5,269 +/- 283 (250.9); and EPO, 12,174 +/- 859 (171.5). Basophils from a normal person contained (in ng/10(6) cells) MBP, 2,374; EDN, 214; ECP, 77; and EPO, 17. Highly purified neutrophils contained (in ng/10(6) cells) MBP, 3 +/- 0.5; EDN, 72 +/- 9; and ECP, 50 +/- 12. Therefore we conclude that these proteins are mainly expressed in eosinophils, but that certain ones are present in basophils and neutrophils.

Basophils

Interaction of eosinophil granule major basic protein with synthetic lipid bilayers: a mechanism for toxicity.

Eosinophil granule major basic protein (MBP) is a potent toxin for mammalian cells and helminths, but the mechanism of its toxicity is not known. Here we tested whether MBP toxicity is exerted through its effect on the lipid bilayer of its targets. Liposomes prepared from synthetic phospholipids were used as targets for MBP and their properties examined by fluorescence and circular dichroism (CD) spectroscopy. MBP caused a change in the temperature transition profiles of acidic liposomes (1-palmitoyl-2-oleoyl-sn-glycero-3-phosphatidyl serine or an equimolar mixture of 1,2-dimyristoyl-sn-glycero-3-phosphocholine and 1,2-dimyristoyl-sn-glycero-3-phosphatidic acid) and induced their aggregation as shown by fluorescence resonance energy transfer experiments. The CD spectra and fluorescence characteristics of MBP itself were altered by its interaction with acidic lipids. Blue shifts in the emission maxima of the Trp, and of the dimethylaminonaphthyl moiety in acrylodan-labeled MBP, and a reduction in the effectiveness of quenching of Trp fluorescence by acrylamide were observed in the presence of acidic lipids. None of these effects were noted with zwitterionic lipids. This MBP: lipid bilayer interaction resulted in fusion and lysis of liposomes as indicated by the fluorescent indicator calcein. The results demonstrate that MBP associates with acidic lipids and that it disrupts, aggregates, fuses, and lyses liposomes prepared from such lipids. Such interaction might account for its wide range of toxicity.

Acrylamide

Deposition of eosinophil granule major basic protein in eosinophilic gastroenteritis and celiac disease.

Degrees of eosinophil infiltration and eosinophil degranulation, as evidenced by localization of the eosinophil granule major basic protein (MBP), were compared in patients with eosinophilic gastroenteritis, patients with celiac disease, and healthy controls using a specific indirect immunofluorescence technique for the localization of MBP. Formalin-fixed, paraffin-embedded biopsy specimens from the mucosa of the stomach and small intestine of 11 patients with eosinophilic gastroenteritis, from the small intestine of 4 patients with celiac disease, and from the stomach and/or upper small intestine of 18 healthy asymptomatic volunteers were tested. Degrees of eosinophil infiltration and extracellular deposition of MBP were graded by two blinded observers; each section was given a score from 0 (nil) to 4 (marked). In the small bowel biopsy specimens, both eosinophil infiltration and extracellular MBP deposition scores were significantly greater in patients with eosinophilic gastroenteritis and in patients with celiac disease than in controls. In the gastric biopsy specimens, extracellular MBP deposition scores were significantly increased in patients with eosinophilic gastroenteritis compared with controls even though eosinophil infiltration scores did not differ significantly at this site. The results support the hypothesis that the eosinophil, through toxic cationic proteins such as MBP, plays a role in the pathogenesis of these diseases.

Adolescent

Pregnancy-associated major basic protein in amniotic fluid.

The pregnancy-associated major basic protein, a protein elevated in the sera of all pregnant women, is virtually identical to the eosinophil granule major basic protein. To determine whether pregnancy-associated major basic protein is present in amniotic fluid, we examined samples from both early and late gestation by a double antibody radioimmunoassay. A total of 112 amniotic fluids were tested and all but three contained levels of pregnancy-associated major basic protein greater than 400 ng/ml. Amniotic fluid pregnancy-associated major basic protein antigenic activity was immunochemically identical to that of the eosinophil granule major basic protein and also had identical physicochemical properties such as heat stability and the need for reduction and alkylation. Although the majority of amniotic fluid samples (90 of 112) were obtained from healthy women with normal gestations, the remaining 21 amniotic fluid samples were from women with Rh sensitization and from one gestation complicated by intrauterine growth retardation.

Amniotic Fluid

Eosinophils 1992.

This report from a recent meeting* highlights some of the key developments in eosinophil research and assesses their impact on current views of the role of eosinophils in inflammation. Considerable progress has been made in defining the structure, constituents and properties of eosinophils in vitro and these new insights into eosinophil biology are summarized. A new era is beginning in which the roles of eosinophils can be assessed and defined in vivo.

Animals

Maternal floor infarction: relationship to X cells, major basic protein, and adverse perinatal outcome.

OBJECTIVE: Maternal floor infarction of the placenta is characterized by gross placental abnormalities and histologic evidence of X-cell proliferation. Previously, pregnancy-associated major basic protein has been localized to the placental X cell and identified at elevated levels in serum and amniotic fluid in all normal pregnancies. Here we test the hypothesis that pregnancy-associated major basic protein is localized to the X cells in maternal floor infarction and that it contributes to the pathophysiologic features of pregnancies complicated by maternal floor infarction. STUDY DESIGN: Seven patients with eight pregnancies complicated by maternal floor infarction were evaluated. We analyzed placental tissue, serum, amniotic fluid, and placental cyst fluid for pregnancy-associated major basic protein. RESULTS: Placental tissue from pregnancies complicated by maternal floor infarction had increased numbers of X cells and fibrinoid material that occupied or surrounded degenerating villi and that stained intensely for pregnancy-associated major basic protein. Serum pregnancy-associated major basic protein levels were variable and likely cannot be used to predict the occurrence of maternal floor infarction. CONCLUSION: Pregnancy-associated major basic protein, a potent cytotoxin, is localized to X cells and is deposited in close proximity to chorionic villi in maternal floor infarction and may contribute to the pathophysiology of this disorder.

Adult

High synovial immunoglobulin E levels in eosinophilic synovitis.

Eosinophilic synovitis occurred in a 7-year-old boy. Synovial fluid leukocytes were mostly eosinophils; the peripheral blood showed only mild eosinophilia. The level of eosinophil-derived neurotoxin in the synovial fluid was higher than that in the serum, suggesting intraarticular eosinophil degranulation. The IgE level was also elevated in the synovial fluid (3854 ng/ml) but normal in the serum (408 ng/ml), suggesting a localized immediate hypersensitivity immune response.

Child

3-(Phenylamino)alanine, a novel aniline-derived amino acid associated with the eosinophilia-myalgia syndrome: a link to the toxic oil syndrome?

The eosinophilia-myalgia syndrome (EMS) is an inflammatory disease that occurred in epidemic proportions in the United States during 1989. Cases of EMS were also reported in Europe and elsewhere. Clinically, EMS resembles the Spanish toxic oil syndrome. EMS has been associated with ingestion of manufactured L-tryptophan and, more specifically, with lots of tryptophan that contained the trace contaminant 1,1'-ethylidenebis(tryptophan) (EBT). Another trace contaminant ("peak UV-5") has been reported, but the strength of its association with EMS has not been demonstrated. Herein we report independently that peak UV-5 is 3-(phenylamino)alanine (PAA). Patients with EMS ingested significantly greater amounts of both PAA and EBT than did control tryptophan users. PAA is chemically similar to 3-phenylamino-1,2-propanediol, an aniline derivative isolated from samples of oil that were consumed by persons in whom the toxic oil syndrome developed. The discovery of an aniline-derived contaminant in tryptophan raises the possibility that EMS and toxic oil syndrome may have a common etiologic trigger.

Alanine

Platelet activation in the lung after antigen challenge in a model of allergic asthma.

The purpose of this study was to investigate whether platelets are activated and release their products in the human lung after antigen challenge. Using subsegmental antigen challenge as a model of asthma, bronchoalveolar lavage fluids from ragweed-allergic asthmatic subjects were assayed for the alpha granule products, platelet factor 4 (PF4) and beta-thromboglobulin (beta-TG), prior to challenge (baseline) and at 5 min and 19 h after challenge with ragweed antigen. Airway segments challenged with normal saline were used as controls. Five minutes after antigen challenge, levels of platelet products in BAL fluid were not elevated from baseline or normal saline control levels. However, 19 h after antigen challenge, a 10-fold increase in platelet products in BAL fluids was found. The mean PF4 levels increased from baseline and saline control values of less than 1.0 to 7.2 ng/ml (p less than 0.05) 19 h after antigen challenge. beta-TG increased from baseline and control levels of less than 1.0 to 6.6 ng/ml (p less than 0.05). Elevations in PF4 and beta-TG were highly correlated with each other (r = 0.98, p less than 0.0001). Levels of platelet products during the 19-h response correlated with albumin, with kinins, with the prostaglandins 6-keto-PGF1 alpha, PGE2, and PGF2 alpha, and with the eosinophil-derived proteins, eosinophil-derived neurotoxin and eosinophil peroxidase. We conclude that platelet activation in the lung is a feature of the late inflammatory response to antigen challenge and that platelets may play an important role in allergic inflammation and asthma.

Adult