Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “EOSINOPHILS”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 289 records · Page 16Linked to original sources
PubMed2005

Immunohistochemical differentiation of eosinophilic heart diseases using antibodies against eosinophil activation markers.

AIMS: Eosinophilic heart syndromes are rare in Western countries and include endocarditis parietalis fibroplastica (EPF) and hypersensitivity myocarditis (HM). There are striking differences in natural history and morphological findings. Since diagnosis can be difficult when analysing small myocardial biopsies lacking the characteristic histological features, we studied a set of immunohistochemical markers in order to characterize the activation status of the infiltrating eosinophils to distinguish between these two entities. METHODS AND RESULTS: This study is based on the investigation of seven explanted hearts and one left ventricular specimen collected during implantation of a left ventricular assist device from a total of seven patients with HM. Also investigated were three right and three left ventricular specimens from five patients with EPF. We used antibodies (Ab) against EG1, and EG2, CD44, and CD69 which have been described as markers to distinguish between resting and activated eosinophils. The EG1 to EG2 ratio of eosinophils and the immunoreactivity against CD44 showed no differences between the two entities. However, eosinophils in the EPF were completely negative for CD69, whereas eosinophils reacted positively within the HM group. CONCLUSION: The immunohistochemical investigation of eosinophilic heart diseases using antibodies against CD69 can be a useful tool to distinguish between hypersensitivity myocarditis and endocarditis parietalis fibroplastica.

Aged↗
PubMed1991

Eosinophil-larval-interaction in onchocerciasis: heterogeneity of in vitro adherence of eosinophils to infective third and fourth stage larvae and microfilariae of Onchocerca volvulus.

Adherence of eosinophilic granulocytes from patients with onchocerciasis to microfilariae (Mf), third (L3) and fourth (L4) stage larvae of Onchocerca volvulus was studied in vitro. Native and heat-inactivated sera from patients with onchocerciasis (OS), from endemic controls without signs of the disease (ECS), from healthy Caucasians (NS) or foetal calf serum (FCS) served as sources for adherence mediating factors. In FCS-supplemented medium eosinophils did not adhere to any larvae. None of the sera mediated the adherence of eosinophils to L4. Eosinophils adhered to L3 in the presence of OS, ECS and NS, whereas OS exclusively mediated adherence to Mf. Reduced adherence rates of eosinophils to L3 occurred in heat-inactivated or zymosan-activated OS, ECS or CS. Eosinophils bound to the L3 cuticle of moulting stage but not to the newly exposed L4 cuticle. A single adherent layer of effector cells was found around cast L3 cuticle, multiple layers were found around intact L3 leading to subsequent paralysis of the larvae and to an amplification of the toxic effector potential by homotypic intereosinophilic adhesion. Our experiments document heterogeneity of in vitro effector cell adherence to the three larval stages of O. volvulus and indicate that complement-dependent as well as independent mechanisms are operative in eosinophil-larval-interaction. The results emphasize the importance of the invading infective larval stages of O. volvulus as possible targets for vaccine production.

Animals↗
PubMed1999

Eosinophilic myocarditis associated with dense deposits of eosinophil cationic protein (ECP) in endomyocardium with high serum ECP.

A case of eosinophilic myocarditis following high serum levels of eosinophil cationic protein (ECP) is described. A 27 year old woman was admitted with New York Heart Association (NYHA) class III congestive heart failure. A haematological study showed hypereosinophilia with degranulation and vacuoles; the total eosinophil count was 7980/ml and the ECP serum concentration was noticeably high at 150 ng/ml. Endomyocardial biopsy from the right ventricle showed infiltration of eosinophils and dense deposits of ECP in the endocardium as well as the myocardium. Steroid treatment returned the total eosinophil count and serum ECP to normal, with satisfactory improvement in clinical features. Eosinophilia may cause cardiac damage, and this report confirms that eosinophil degranulation is toxic. Thus, serum ECP seems to be a reliable indicator for diagnosis and for determining treatment parameters of eosinophilic myocarditis.

Adult↗
PubMed1999

Interleukin (IL)-5 downregulates tumor necrosis factor (TNF)-induced eotaxin messenger RNA (mRNA) expression in eosinophils. Induction of eotaxin mRNA by TNF and IL-5 in eosinophils.

An eotaxin is a chemoattractant specific for eosinophils that are known to play a role in helminth infection and allergic responses. Although several cellular sources have been reported to produce eotaxin, it would be interesting to know whether eosinophils are able to produce their own eotaxin and participate in recruitment of themselves in response to inflammation. To this end, a cloned eotaxin complementary DNA was transcribed in vitro to use as a probe for detecting eotaxin messenger RNA (mRNA), and eotaxin protein levels were determined by enzyme-linked immunosorbent assay. Eotaxin mRNA was, as analyzed by in situ hybridization, rarely detectable in unstimulated eosinophils, but was strongly induced in eosinophils when stimulated with tumor necrosis factor (TNF). Interleukin (IL)-5, which is known to be a major factor of eosinophil survival in vivo and in vitro, was also able to induce a modest level of eotaxin mRNA but inhibited TNF-induced eotaxin mRNA expression in a dose-response manner. Dexamethasone inhibited TNF-induced eotaxin mRNA expression. This result was consistent with that from reverse transcription/polymerase chain reaction followed by Southern blot analysis. Unlike the little expression of eotaxin mRNA in the absence of stimuli, the measurement of eotaxin protein revealed that a considerable amount of eotaxin protein was constitutively produced in unstimulated eosinophils. Its expression was upregulated by TNF and IL-5 as well. However, the inhibitory effect of IL-5 on TNF-mediated eotaxin protein production was not as pronounced as that on eotaxin mRNA induction. Collectively, these data reflect the complex physiology of eosinophils in the expression of eotaxin gene upon the exposure to their survival and/or death factors.

Chemokine CCL11↗
PubMed1996

Increased respiratory burst and phosphodiesterase activity in alveolar eosinophils in chronic eosinophilic pneumonia.

A 43 year old woman presented with chronic eosinophilic pneumonia characterised by a high alveolar eosinophilic count, which allowed biochemical study of these cells. Alveolar eosinophils spontaneously produced high amounts of oxygen free radicals and exhibited an increased level of cyclic adenosine monophosphate (cAMP) phosphodiesterase (PDE) activity compared to blood eosinophils from control or allergic subjects. This activity was preferentially located in the plasma membrane, whilst the PDE activity of blood eosinophils from asthmatics or controls predominated in the cytosol. Because of the potential role of phosphodiesterase during eosinophil activation and recruitment, phosphodiesterase inhibitors may be useful in the treatment of eosinophilic pneumonia.

3',5'-Cyclic-AMP Phosphodiesterases↗
PubMed2004

2-arachidonoylglycerol, an endogenous cannabinoid receptor ligand, induces the migration of EoL-1 human eosinophilic leukemia cells and human peripheral blood eosinophils.

2-arachidonoylglycerol (2-AG) is an endogenous cannabinoid receptor ligand. To date, two types of cannabinoid receptors have been identified: the CB1 receptor, abundantly expressed in the brain, and the CB2 receptor, expressed in various lymphoid tissues such as the spleen. The CB1 receptor has been assumed to play an important role in the regulation of synaptic transmission, whereas the physiological roles of the CB2 receptor remain obscure. In this study, we examined whether the CB2 receptor is present in human eosinophils and found that the CB2 receptor is expressed in human peripheral blood eosinophils. In contrast, human neutrophils do not contain a significant amount of the CB2 receptor. We then examined the effect of 2-AG on the motility of eosinophils. We found that 2-AG induces the migration of human eosinophilic leukemia EoL-1 cells. The migration evoked by 2-AG was abolished in the presence of SR144528, a CB2 receptor antagonist, or by pretreatment of the cells with pertussis toxin, suggesting that the CB2 receptor and Gi/o are involved in the 2-AG-induced migration. The migration of EoL-1 cells induced by 2-AG was suggested to be a result of chemotaxis. In contrast to 2-AG, neither anandamide nor free arachidonic acid elicited the migration. Finally, we examined the effect of 2-AG on human peripheral blood eosinophils and neutrophils and found that 2-AG induces migration of eosinophils but not neutrophils. These results suggest that the CB2 receptor and its endogenous ligand 2-AG may be closely involved in allergic inflammation accompanied by the infiltration of eosinophils.

Arachidonic Acid↗
PubMed2001

Functional expression of IL-12 receptor by human eosinophils: IL-12 promotes eosinophil apoptosis.

In murine models of allergic inflammation, IL-12 has been shown to decrease tissue eosinophilia, but the underlying mechanisms are not known. We evaluated the expression of IL-12R and the effect of IL-12 on eosinophil survival. In situ hybridization demonstrated the presence of mRNA and immunoreactivity for IL-12Rbeta1 and -beta2 subunits in human peripheral blood eosinophils. Surface expression of IL-12Rbeta1 and -beta2 subunits on freshly isolated human eosinophils was optimally expressed after incubation with PMA. To determine the functional significance of IL-12R studies, we studied cell viability and apoptosis. Morphological analysis and propidium iodide staining for cell cycle demonstrated that recombinant human IL-12 increased in vitro human eosinophil apoptosis in a dose-dependent manner. Addition of IL-5 together with IL-12 abrogated eosinophil apoptosis, suggesting that IL-12 and IL-5 have antagonistic effects. Our findings provide evidence for a novel role for IL-12 in regulating eosinophil function by increasing eosinophil apoptosis.

Apoptosis↗
PubMed1991

[The inhibitory effect of oxatomide on oxygen radical products from human eosinophils and an eosinophilic cell line].

Recently, much attention has been paid to the role played by the allergic inflammatory reaction in the role of asthma. Eosinophils are considered to be major inflammatory cells in bronchial asthma. Therefore, in this study, eosinophil-mediated oxygen radicals were examined by means of luminol-dependent chemiluminescence. Also, the effect of oxatomide, an anti-allergic agent, which has an inhibitory effect on eosinophil-mediated natural cytotoxicity against bronchial epithelial cells, on the production of oxygen radicals from eosinophils was studied. The results revealed the inhibitory effects of oxatomide on eosinophil-mediated oxygen radicals products. Furthermore, the inhibitory effect of this agent on oxygen radical products from eosinophilic cell-line named EoL-3, which has been established recently, was observed. We concluded from these results that oxatomide not only has anti-allergic activity but also anti-inflammatory properties for eosinophils.

Anti-Inflammatory Agents↗
PubMed1988

Ultrastructural study of eosinophils from patients with the hypereosinophilic syndrome: a morphological basis of hypodense eosinophils.

We investigated the ultrastructural characteristics and the granule major basic protein (MBP) content of hypodense eosinophils from patients with the hypereosinophilic syndrome who had at least 90% hypodense eosinophils in their peripheral blood and compared these cells to normodense eosinophils from normal persons. The hypodense cells (density less than 1.082) contained significantly less MBP than normodense (density greater than 1.082) eosinophils (P less than .001) as measured by radioimmunoassay (RIA). Electron microscopic examination demonstrated a mean of 25.0 +/- 4.4 (X +/- 1 SD) granules per hypodense cell, compared to 30.6 +/- 8.4 granules per cell in the normodense group (P less than .1). The most striking difference between the hypodense and normodense eosinophils was the small individual granule size (X = .14 +/- .05 v .26 +/- .05 micron 2, respectively, P less than .001), and the smaller total granule area (3.2 +/- 1.8 vs 7.7 +/- 3.1 micron 2, respectively, P less than .001). Because the cytoplasmic areas were similar in the two groups, the mean percent area of cytoplasm occupied by granules was significantly lower in the hypodense group (P less than .001). The finding of consistently smaller granules in the presence of equal or fewer granules per cell in the hypodense eosinophils may explain the lower MBP content and thus provide a morphologic basis for the low density of eosinophils in patients with the hypereosinophilic syndrome.

Densitometry↗
PubMed1986

The effects of eosinophil activating factor on IgG-dependent sulphidopeptide leukotriene generation by human eosinophils.

Eosinophil activating factor (EAF) is a 40 kD protein released from cultured, unstimulated human monocytes which enhances the IgG-dependent eosinophil-mediated cytotoxicity of helminthic larvae. We have recently shown that eosinophils elaborate substantial quantities of leukotriene C4 (LTC4) during incubation with IgG-coated particles and now report that EAF, partially purified by sequential chromatography on Sephacryl S-200 and DEAE-cellulose, enhanced this IgG-dependent LTC4 production by human eosinophils in a dose- and time-dependent fashion. LTC4 production by normal density eosinophils, separated on discontinuous metrizamide gradients, was significantly increased after incubation with several dilutions of EAF (P less than 0.05), although an increase was not seen with low density cells. The enhancement was similar in degree to that seen when normal density eosinophils were activated with the bacterial analogue, f-met-leu-phe (fMLP). EAF produced a time-dependent increase in LTC4 which was significantly greater (P less than 0.01) than the control. Sulphidopeptide leukotriene (LT) generation was validated by reverse phase high pressure liquid chromatography (RP-HPLC). These results indicate that there is a firm association between monocytes, eosinophils and LTC4; an observation which may be of relevance to mechanisms in chronic asthma and related disorders, and in immune reactions against migrating helminthic larvae.

Dose-Response Relationship, Drug↗
PubMed1978

Anisakis and eosinophil. I. Detection of a soluble factor selectively chemotactic for eosinophils in the extract from Anisakis larvae.

Studies were undertaken in order to determine if Anisakis larva itself has the ability to attract eosinophils. Extracts from Anisakis larvae were examined for both neutrophil and eosinophil chemotactic activities with both in vivo and in vitro assay systems. When the soluble extract was injected intradermally into normal guinea pigs, a profound accumulation of eosinophils was observed at the injection site. The cells started to accumulate at the site within 1 hr and the number of eosinophils at the site reached its peak at 8 hr after the injection of the extract. Such eosinophilic accumulation was enhanced in a dose-response fashion over the range of 0.5 to 50 micrograms protein. The strong chemotatic activity of the Anisakis extract for eosinophils was confirmed when in vitro chemotaxis assays were performed with Boyden chemotatic chambers. Interestingly, no chemotactic activity for neutrophils was found at those concentrations of the extract with which the eosinophil effect was observed. These results indicate that the factor described here, in addition to the various known immunologic factors, may play an important role in the development of eosinophilia in anisakiasis.

Animals↗
PubMed1993

Corticosteroid resistance in eosinophilic gastritis--relation to in vitro eosinophil survival and interleukin 5.

Eosinophilic gastritis is usually responsive to corticosteroid therapy. In some cases, large doses and protracted treatment are required. This report describes a case of eosinophilic gastritis that was partially corticosteroid resistant. To determine mechanisms that explain this patient's incomplete response to corticosteroid therapy, peripheral blood eosinophils and serum were isolated from the patient. We found the in vitro survival of the patient's eosinophils was prolonged. In addition, his serum both promoted in vitro eosinophil survival and nullified the survival inhibiting of effect of hydrocortisone (10 microM). Furthermore, antibody against interleukin 5 (IL5) partially inhibited the enhanced eosinophil survival produced by the patient's serum and completely blocked the decrease in survival resulting from hydrocortisone. These observations indicate that elevated circulating levels of IL5 may contribute to the peripheral eosinophilia and corticosteroid resistance in some patients with eosinophilic gastritis.

Adrenal Cortex Hormones↗
PubMed1988

Eosinophil granule cationic proteins: major basic protein is distinct from the smaller subunit of eosinophil peroxidase.

Major basic protein and eosinophil peroxidase are predominant cationic proteins in the cytoplasmic granules of human eosinophilic leukocytes. Each of these proteins has been purified, and major basic protein and the lower molecular weight subunit of eosinophil peroxidase have been found to comigrate on polyacrylamide gel electrophoresis in sodium dodecyl sulfate with similar apparent molecular weights of about 14,700. Because previous molecular weight estimates for these proteins have not recognized the similar molecular weights of these two cationic eosinophil granule constituents, we have evaluated the possible relatedness of these proteins. Upon protein sequence analyses, it was found that the N-terminal 20 amino acid residues of each of these two purified polypeptides differed. These findings established that major basic protein and the smaller subunit of eosinophil peroxidase, although of comparable molecular weights, are two distinct proteins within the cytoplasmic granules of human eosinophils.

Amino Acid Sequence↗
PubMed1989

Major basic protein and eosinophil-derived neurotoxin concentrations in nasal-lavage fluid after antigen challenge: effect of systemic corticosteroids and relationship to eosinophil influx.

The late-phase response to nasal challenge with antigen is associated with a mixed inflammatory cell influx in which the eosinophil demonstrates the earliest and greatest proportionate rise. We investigated the evidence for activation of the eosinophil during the late response by measuring the concentration of the eosinophil-derived mediator major basic protein (MBP) and the eosinophil-derived neurotoxin (EDN) in nasal-lavage fluids before and for 11 hours after antigen challenge in 13 subjects with seasonal allergic rhinitis. The subjects received oral prednisone (20 mg three times daily) or placebo in a double-blind, crossover manner for 2 days before each of two antigen challenges. After placebo pretreatment, significant increases over diluent baseline (4.5 +/- 0.4 ng/ml) occurred in the levels of MBP in nasal-lavage fluid during the early (9.8 +/- 2.9 ng/ml; p less than 0.005) and late (15.3 +/- 4.8 ng/ml; p less than 0.01) responses to antigen challenge. Significant increases (p less than 0.05) in the concentration of EDN also occurred during the late response to antigen that correlated with the levels of MBP (r = 0.48; p less than 0.001). The cumulative late-phase increase in MBP correlated closely (rs = 0.96; p less than 0.005) with the total influx of eosinophils. Oral prednisone pretreatment significantly reduced the mean of each subject's peak late-phase concentration of both MBP (30.7 +/- 5.8 ng/ml versus 13.3 +/- 4.3 ng/ml; p = 0.005) and EDN (885 +/- 659 ng/ml versus 71 +/- 41 ng/ml; p less than 0.05). These data provide evidence for eosinophil degranulation during the late response and inhibition of this response by prednisone, supporting its pathogenetic role.

Blood Proteins↗
PubMed2000

Urinary eosinophil protein X and serum eosinophil cationic protein in infants and young children with atopic dermatitis: correlation with disease activity.

BACKGROUND: Eosinophil cationic protein (ECP) and eosinophil protein X (EPX) or eosinophil-derived neurotoxin (EDN) are released by eosinophil granulocytes in allergic diseases. Serum ECP (s-ECP) levels have been correlated with disease activity in atopic dermatitis (AD) in adults and young patients, and high urinary EPX (u-EPX) levels in asthmatic patients seem to reflect active disease. A relationship between AD severity and u-EPX concentration in young children has not been previously studied. OBJECTIVE: This study was performed to evaluate whether the severity of AD in infants and young children was correlated with s-ECP and u-EPX levels. METHODS: Fifty-four infants and children (mean age, 17.7 months; range, 4-48 months) with AD and without other allergic conditions were evaluated. The severity of AD was measured by using the SCORAD index. S-ECP, serum total IgE, serum-specific IgE for common allergens, and peripheral blood eosinophil counts (PBECs) were determined. In forty-two children u-EPX was also measured. Seven age-matched control patients underwent the same determinations. RESULTS: S-ECP and u-EPX were significantly higher in children with AD than in control children (mean, 23.9 vs 3.5 microg/dL [P <.001] and 57.7 vs 6.0 microg/mmol creatinine [P <.001]). A significant correlation was found between SCORAD and s-ECP (P =.002), u-EPX (P =.01), and PBECs (P =.01) and between symptom index and uEPX (P =.0004). PBECs were strongly correlated to s-ECP and u-EPX (P <.0001). However, 5 patients with moderate and severe AD (11.9%) showed low levels of s-ECP, u-EPX, and PBECs. CONCLUSION: S-ECP and u-EPX were useful markers of AD activity in infants and young children. When taken together, the two determinations could give more information about the clinical course of the illness. Some patients seemed to have clinical exacerbations without an involvement of eosinophils and their products.

Blood Proteins↗
PubMed1999

Intracellular expression and serum levels of eosinophil peroxidase (EPO) and eosinophil cationic protein in asthmatic children.

BACKGROUND: Eosinophils are involved in the chronic inflammatory response in asthma and their basic proteins are thought to play a major pathophysiological role in this process. While serum levels of basic proteins have been used to monitor the ongoing allergic disease, little is known about the intracellular expression of these proteins in clinical situations. OBJECTIVE: The aim of the study was to determine the intracellular expression of eosinophil cationic protein (ECP) and eosinophil peroxidase (EPO) in asthmatic children and control subjects and relate it to serum levels of both proteins, lung function tests and immunoglobulin (Ig)E levels. METHODS: Serum ECP and EPO concentrations were determined by immunoassays in 13 asthmatic children (mean age: 9 +/- 1 years, mean FEV1: 92 +/- 10% predicted, geometric mean PC20 histamine 0.5 mg/mL) and 10 age-matched, healthy control subjects. A flow cytometric single cell assay was employed to detect intracellular ECP and EPO in peripheral blood eosinophils. RESULTS: While serum concentrations of both ECP (asthma: median 15.0 microg/L [range 3.6-57.7] vs control: 5.9 microg/L [2.7-9.1]; P = 0.02) and EPO (22.9 microg/L [5.2-82.5] vs 7. 2 microg/L [2.5-12.7]; P = 0.008) were significantly elevated in asthmatics, the intracellular expression of ECP and EPO (measured as mean fluorescence intensity) was decreased (EG1: 55.3 [17.7-120.8] vs 100.3 [46.5-264.4]; P = 0.01; EG2: 80.2 [24.1-135.3] vs 133.7 [32. 1-244.9]; P = 0.04 and EPO: 49.7 [23.1-155.8] vs 94.9 [28.8-115.2]; P = 0.03). In asthmatics there was a significant correlation of FEV1 with intracellular ECP and of bronchial hyperresponsiveness with serum EPO and ECP. Furthermore, total IgE levels were positively correlated with serum EPO only. CONCLUSION: We conclude that in asthmatics the intracellular content of ECP and EPO in peripheral eosinophils is reduced possibly due to degranulation. Epitope masking in activated eosinophils or a shift to early bone marrow-derived progenitors with less granule proteins are further possible explanations.

Asthma↗
PubMed1994

Inhibitors of chymotrypsin-like proteases inhibit eosinophil peroxidase release from activated human eosinophils.

Eosinophils contain many cytotoxic mediators including eosinophil peroxidase (EPO) in their granules; on degranulation, these mediators are released by various pathophysiological stimuli, resulting in severe tissue damage. However, little is known about inhibitors of degranulation. Here, we report that eosinophils isolated from patients with bronchial asthma have significant chymotrypsin-like serine protease activity in the high salt extract fraction. The protease partially purified and labeled with [3H]diisopropylfluorophosphate has an apparent molecular mass of 28 kDa on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The chymotrypsin-like protease was not immunoreactive with antibodies against chymase and atypical chymase from rat mast cells or with an antibody against cathepsin G from human neutrophils. Studies on the subcellular distribution of the chymotrypsin-like protease indicated that the enzyme is mainly localized with EPO in eosinophil granules. Chymostatin, an inhibitor of the chymotrypsin-like protease(s), but not an inhibitor of other types of proteases, markedly inhibited the EPO release from eosinophils that was induced by immunoglobulin G plus rIL-5 or platelet-activating factor, although it had no effect on the release of EPO induced by the calcium ionophore A23187. These results suggest that proteolytic activation by chymotrypsin-like serine protease(s) in eosinophils plays some role in the process of receptor-mediated EPO release from the granules.

Affinity Labels↗
PubMed1994

The role of eosinophils and eosinophil cationic protein in monitoring oral challenge tests in children with food-sensitive atopic dermatitis.

To investigate the role of peripheral blood eosinophils and eosinophil cationic protein as parameters in monitoring oral food challenges, we monitored 25 infants and children with atopic dermatitis for up to 48 hours after 47 placebo-controlled oral food challenges with cow's milk, hen's egg, cow's milk and hen's egg, or placebo for up to 48 hours. Six healthy young nonatopic adult volunteers served as control subjects. Compared with baseline values, peripheral blood eosinophils decreased significantly immediately after clinical reaction in positive challenges (p < 0.0004), independent of the kind of reaction. Eosinophil cationic protein increased significantly 8 hours after provocation, with a maximum at 24 hours (p < 0.03). This increase was predominantly related to eczematous reactions (p < 0.005). Blood sampling immediately after clinical reaction (for eosinophils) and at 24 hours (for eosinophil cationic protein) seems to be useful in monitoring oral food challenges in children with atopic dermatitis.

Adolescent↗