Protection of montelukast on OVA-induced eosinophilic gastroenteritis via modulating IL-5, eotaxin-1 and MBP expression

Abstract

The aim of this study was to further explore the possible mechanisms of montelukast on oral mice ovalbumin-induced eosinophilic gastroenteritis in a mouse model. The results indicated that montelukast could prevent levels of eotaxin-1 and interleukin-5 in intestinal mucosa homogenate when compared with model group. Interestingly, the increase of major basic protein expression in jejunal tissue also was attenuated by treated with montelukast.     

Sodium cromoglycate in the treatment of eosinophilic gastroenteritis

Two patients suffering from eosinophilic gastroenteritis (EG) were treated with sodium cromoglycate (SCG). Before treatment they showed enteric and cutaneous symptoms, such as abdominal pain, nausea, vomiting, diarrhoea and recurrent urticaria and angioedema. The histological findings were a notable amount of eosinophilic infiltration in the lamina propria and gastric glands, a villous shortening and thickening and weak eosinophilic inflammation in the duodenum. The patients were treated with 300 mg SCG, 4 times daily, for 4/5 months. During treatment, the clinical symptoms disappeared and at the end of treatment a reduced inflammation with an almost complete decrease of eosinophilic infiltration was observed. The results provide evidence of SCG efficacy in the treatment of EG and suggest its employment as an alternative to the steroids commonly used in EG.     

Rebound eosinophilia after treatment of hypereosinophilic syndrome and eosinophilic gastroenteritis with monoclonal anti-IL-5 antibody SCH55700

BACKGROUND: Hypereosinophilic syndrome and eosinophilic gastroenteritis with peripheral eosinophilia are characterized by sustained eosinophilia and eosinophil-mediated tissue damage. Although treatment with the humanized monoclonal anti-IL-5 antibody SCH55700 resulted in improvement of eosinophilia and clinical symptoms in 6 of 8 of patients with hypereosinophilic syndrome or eosinophilic gastroenteritis with peripheral eosinophilia for as long as 12 weeks, eosinophil counts subsequently rose above baseline levels, accompanied by an exacerbation of symptoms. OBJECTIVE: To identify the mechanism underlying this rebound eosinophilia. METHODS: Purified eosinophils from patients or normal donors were cultured with IL-5, patient serum, and/or anticytokine antibodies, and eosinophil survival was assessed by flow cytometry. Serum and intracellular cytokine levels were measured by multiplex sandwich ELISA and flow cytometry, respectively. RESULTS: Before treatment with SCH55700, in vitro eosinophil survival in media and in response to recombinant IL-5 was similar in patients and normal donors. At 1 month posttreatment, the eosinophil survival curves were unchanged in 4 of 5 patients in media and in all 5 patients in response to recombinant IL-5. Normal eosinophil survival was prolonged in cultures containing posttreatment but not pretreatment sera (pretreatment vs posttreatment, 10.74% vs 73.02% live cells; P = .01). This posttreatment serum effect on eosinophil survival was reversed by the addition of the monoclonal anti-IL-5 antibody TRFK5. Although increased levels of serum IL-5 were observed at 1 month compared with 2 to 3 days posttreatment in 5 of 6 patients ( P = .04), intracellular cytokine analysis did not reveal increased production of IL-5 by peripheral blood mononuclear cells. CONCLUSIONS: The rebound eosinophilia after SCH55700 treatment is a result of a serum factor that enhances eosinophil survival. Reversal of this effect by the addition of antibody to IL-5 suggests that this factor may be IL-5 itself.     

IgE antibodies against bovine serum albumin in a case of eosinophilic gastroenteritis

Eosinophilic gastroenteritis is a disease characterized histologically by an eosinophilic infiltration of the gut. The cause of this disease remains unclear, although both food allergy and food intolerance have been implicated in its pathogenesis. We report the case of a 22-year-old man in whom gastrointestinal symptoms first appeared in childhood, with involvement of mucosa and muscularis layers of stomach and bowel. He presented high IgE blood levels, and his prick test was positive to bovine, pig, and lamb sera. Immunoblots from calf, pig, and lamb sera, incubated with the patient's serum and revealed by autoradiography, demonstrated the presence of a 65-kDa protein band that was recognized by IgE antibodies but not by IgG. This band corresponded to bovine serum albumin, while IgE did not show reactivity with human albumin. These data suggest a possible role for IgE-mediated hypersensitivity mechanisms in the pathogenesis of eosinophilic gastroenteritis.     

Eosinophilic gastroenteritis and Anisakis

Background The differential diagnosis of eosinophilic gastroenteritis (EG) includes, among other diseases, parasitic infections such as anisakiasis, which has acquired worldwide importance.
Methods We reviewed all patients referred to our allergy service who had been diagnosed as having primary EG to determine the possible role of Anisakis simplex in the etiopathology of the disease. All patients (n= 10) were studied and diagnosed as having primary EG between 1989 and 1996, inclusive. Two different groups of subjects were used as controls: group A (149 subjects without digestive disorder) and group B (10 subjects with digestive disorder different from EG). Cutaneous prick tests were performed with the main foods, aeroallergens, and commercial extract of A. simplex. Total and specific serum IgE was measured in all patients. Gastric or gut histologic specimens were re-examined in five cases.
Results Peripheral eosinophilia was detected in 40% of the patients with EG, and sensitization to A. simplex was detected in 80% of these. In both control groups, the rate of sensitization to A. simplex was 10%. Sensitization to A. simplex in EG patients with respect to control groups A and B showed odds ratios (OR) of 36 and 40, respectively. In one case, serialization of the histologic section allowed us to observe a whole Anisakis larva.
Conclusions Immunologic methods to detect specific antibodies against Anisakis should be used routinely before diagnosing EG as primary disorder. Preventive measures are of capital importance.     

Major basic protein, but not eosinophil cationic protein or eosinophil protein X, is related to atopy in cystic fibrosis.

Increased eosinophil granule proteins have been described in serum and sputum samples of patients with cystic fibrosis (CF). It has been assumed that eosinophil degranulation is enhanced in atopic subjects - as in asthmatics. Since in CF no differences in eosinophil cationic protein (ECP), eosinophil protein X (EPX), and eosinophil peroxidase between atopic and nonatopic subjects have been detected, we investigated whether major basic protein (MBP) is increased in serum and sputum samples derived from atopic (n = 14) compared with nonatopic CF subjects (n = 26). In CF patients, high mean serum (sputum) levels of ECP 29.7 microg/l (2.7 mg/l), EPX 53.7 microg/l (7.9 mg/l), and MBP 984.6 microg/l but low sputum MBP levels (57.4 microg/l) were measured. In addition, in serum and in sputum samples, a significant correlation between MBP and ECP (P<0.03 and P<0.0001, respectively) or EPX (P<0.05 and P<0.0004, respectively) was detected. By subdivision of the patients into allergic and nonallergic subjects, significant differences were found for serum MBP values only(mean 1382.2 microg/l vs. 770.5 microg/l; P<0.0001), but not for ECP or EPX serum levels or for eosinophil proteins in sputum. Although no differences between atopic and nonatopic CF patients in ECP and EPX were found, serum MBP levels were higher in patients sensitized to inhalant allergens than in nonsensitized subjects. These results indicate differential release of eosinophil granule proteins in peripheral blood from eosinophils, and they also indicate that MBP in serum likely is to be a better discriminator of atopy in CF.     

Participation of eosinophils in the toxic oil syndrome.

The participation of eosinophils in the Spanish toxic oil syndrome (TOS) was investigated. Eosinophil infiltration and degranulation in tissues from 52 patients with the TOS were examined by immunofluorescence staining for the eosinophil granule major basic protein (MBP). Serum MBP levels were determined in sera from 323 patients. Eosinophil infiltration and degranulation were found in several tissues, especially during the acute phase of the TOS, and serum MBP was significantly elevated during all phases of the disease, suggesting that eosinophils play a role in the pathogenesis of the TOS.     

Cytochemical characterization of eosinophilic leukocytes circulating in the blood of the turtle (Chrysemys dorbignih)

Eosinophils and neutrophils are granulocytic leukocytes that are present in the blood of most vertebrates. Studies have been performed on lower vertebrates to understand the biological roles of the cells in defense mechanisms and to establish phylogenetic studies and new experimental models. Whether these 2 cell types exist in reptiles is a matter of controversy. In the blood of turtles there are 2 types of granulocytes that exhibit eosinophilia, one of them with round cytoplasmic granules and the other with elongated cytoplasmic granules. It has been suggested that these cells may be eosinophils in different stages of maturation but they also may be distinct cell types, i.e. eosinophils and neutrophils. In the present study, we characterized the 2 types of granulocytes that are present in the blood of Chrysemys dorbignih, using cytochemical techniques. Type I eosinophils showed activity of nonspecific esterase, peroxidase activity that is resistant to KCN, and basic proteins. Type II eosinophils exhibited activity of trimetaphosphatase, alkaline phosphatase, nonspecific esterase, peroxidase that is sensitive to KCN, and basic proteins. These observations indicate the existence of 2 distinct cell types in the blood of Chrysemys dorbignih, type I and type II eosinophils, that correspond to eosinophils and heterophils (neutrophils) of mammals and other vertebrates.     

Eosinophil chemoattractants in the middle ear of patients with eosinophilic otitis media

BACKGROUND: Patients with intractable otitis media associated with bronchial asthma have an extensive accumulation of eosinophils in the effusion and mucosa of the middle ear; this condition is called eosinophilic otitis media (EOM). It remained to be determined how eosinophils accumulate in the middle ear. OBJECTIVES: To clarify the pathogenesis of middle ear diseases, we measured the concentration of eosinophil chemoattractants in middle ear effusion (MEE), and carried out immunohistochemical studies of middle ear mucosa specimens to demonstrate the expression of eosinophil chemoattractants. METHODS: Middle ear effusion samples were obtained from 15 EOM patients with bronchial asthma and from six controls for the measurement of eosinophil cationic protein (ECP), IL-5, eotaxin and regulated on activation, normal T expressed and secreted concentrations. Middle ear mucosa samples were also taken from 14 EOM patients and 16 controls for immunohistochemical study. In 10 EOM patients, the numbers of immunoreactive cells as well as apoptotic cells were determined before and after the topical application of triamcinolone acetonide into the middle ear. RESULTS: In EOM, significantly higher ECP and IL-5 concentrations were detected in MEE than in serum, and ECP, IL-5 and eotaxin concentrations in MEE were higher in the EOM patients than in the controls. ECP concentration positively correlated with that of IL-5. Immunohistochemically, the numbers of cells positive for EG2 and ecalectin were significantly higher in the EOM patients than in the controls. After the topical application of triamcinolone acetonide, the numbers of infiltrating cells and immunoreactive cells distinctly decreased, whereas the number of apoptotic cells significantly increased. CONCLUSION: In EOM, locally produced IL-5 may play a crucial role in the accumulation of eosinophils in the middle ear. Chemokines such as ecalectin and eotaxin are also produced in the middle ear, and help activate and enhance the survival of eosinophils to induce the intractable condition in the middle ear. The topical application of triamcinolone acetonide induces the apoptosis of not only eosinophils but also eosinophil chemoattractant-producing cells, thereby improving the middle ear condition.     

Eosinophilic gastroenteritis

Eosinophilic gastroenteritis is an uncommon condition affecting one or more segments of the gastrointestinal tract, mainly the stomach and small bowell, the principal changes being a variable degree of both oedema and eosinophilic infiltration. Occurring at any age it is commonest in the third decade, is often associated with abdominal pain and peripheral blood eosinophilia, and responds to steroids: allergy or asthma occurs in some 25% of patients. The oedema and eosinophilia involve the submucosa generally but any layer of the gut may be affected. The aetiology is discussed: no allergic or other cause has been determined and it is probable that further knowledge of the role of the eosinophil may be necessary before the precise nature of the lesion can be understood. An association of eosinophilic gastroenteritis with malabsorptive or protein-losing enteropathies is noted.     

The pathology and causes of tissue eosinophilia in the gastrointestinal tract

Eosinophilic inflammation in the gastrointestinal tract may occur as a primary eosinophilic disorder or as a secondary response with other causes. Primary eosinophilic gastrointestinal disorders (EGIDs) are Th2‐mediated allergic diseases that overlap pathogenetically with atopic conditions involving other organs. The pathological diagnosis of primary EGIDs can be challenging, as the quantity of eosinophils considered to be ‘abnormal’ is difficult to define, and the diagnosis, by definition, requires exclusion of the far more common secondary causes. Our understanding of the basic biology and natural history of eosinophilic oesophagitis has advanced considerably over the last decade, whereas other EGIDs have proven more difficult to characterize; nonetheless, some recent advances have been made. This review summarizes current knowledge regarding the clinical presentation, diagnosis, natural history and treatment of EGIDs, including eosinophilic oesophagitis. We also draw attention to the numerous secondary causes of tissue eosinophilia in the gastrointestinal tract, and suggest a practical approach to the histological assessment, diagnosis and reporting of EGIDs.     

A rat model of hypereosinophilic syndrome

Hypereosinophilia-occurring rats without chemical and antigen treatment have been maintained in our laboratory. The rat, Matsumoto Eosinophilia Shinshu (mes), showed hypereosinophilia at the age of 9 weeks or older and developed eosinophil-related inflammatory lesions in many organs. These lesions included: aortitis, granulomatous lesion in the mesenteric lymph node, inflammatory fibroid polyp of the stomach and pulmonary vasculitis with septal infiltration. These lesions were involved with cellular infiltration of eosinophils and macrophages, and deposition of eosinophilic crystals which immunohistologically showed major basic protein and eosinophilic peroxidase derived from eosinophilic lysosomal constituents. Although the distribution of lesions in mes is a little different from that of hypereosinophilic syndrome (HES) in humans, in that endomyocardial fibrosis appears in HES while aortitis appears in mes, mes is probably comparable with HES. The present paper describes the pathological aspects of the lesions in mes and discusses the pathogenesis of tissue injury related to eosinophilic infiltration.     

Clinical value of serum eosinophilic cationic protein assessment in children with inflammatory bowel disease

Introduction

Eosinophils contribute to the pathogenesis of inflammatory bowel disease (IBD) in the intestine. Eosinophilic cationic protein (ECP) is one of the most important eosinophilic specific mediators released during activation. The aim of the study was to evaluate the clinical value of serum ECP determination in children with active and inactive IBD and its correlation with disease activity.

Material and methods

There were 125 children with IBD (63 with Crohn''s disease – CD, 44 with ulcerative colitis – UC, 18 indeterminate colitis – IC) enrolled in the study. Among them 83 children were in the active phase of the disease, while the remaining 42 were in remission. The control group consisted of 56 healthy children. The ECP was assessed three times in children with active IBD, at baseline and after 2 and 6 weeks of treatment and once in children with inactive IBD and controls using fluoroenzymeimmunoassays.

Results

We found elevated ECP at baseline in the total active IBD group when compared to the inactive IBD and control groups, decreasing during treatment. Serum ECP was also elevated in the active UC and CD groups when compared to the inactive UC and CD groups, and correlated with clinical UC and CD activity (R = 0.57 and R = 0.52, p < 0.05, respectively) and duration of the clinical manifestation in UC (R = 0.62, p < 0.05) but not with the disease location in the gastrointestinal tract, or endoscopic and histopathological activity.

Conclusions

Evaluation of serum ECP in children with IBD may be useful in disease activity assessment at onset and during the treatment.     

Presence of eosinophilic precursors in the human thymus: Evidence for intra-thymic differentiation of cells in eosinophilic lineage

The distribution of myeloid cells in the human thymus was investigated by light and electron microscopy, immuno-histochemistry, andlor flow cytometry. A series of 74 thymic samples, from newborn to 37 year old patients, were studied. By light microscopy, aggregates of mononuclear cells were frequently present in intralobular septa and outer medulla. Among those cells, eosinophilic precursors (promyelocyte, myelocytes and metamyelocytes) were readily identified. These immature granular cells were present in all pre-invo-lutional thymi, and were particularly frequent in the thymi of patients who were younger than 5 years of age. The cells made up 30–50% of the total eosinophilic population and were frequently observed asagroupof cells at variousstages of differentiation, suggesting that they differentiate from preexisting precursors in the thymus. These eosinophilic precursors were mostly located in the intralobular septa and f ibroreticular network at the corticomedullary junction, while mature eosinophils were scattered throughout the thymus. Flow cytometric analyses, using stem cellenriched preparations, showed that cells expressing CD33 or CD34 constituted on average 2.55% and 3.33% (0.09% and 0.12% of the total cells), respectively. CD33+/CD34+ coexpressors were also identified, and they constituted 0.36% of the analyzed cells (0.01% of the total cells). No statistical difference in the proportions of CD33+ andlor 34' cells was noted between any age groups. It is concluded that eosinophilic precursors present in the thymus differentiate into cells in the eosinophilic lineage in particular areas such as the intralobular septa and f ibroreticular network of the outer medulla in pt'ein-volutional human thymi.