Eotaxin-3 and a uniquely conserved gene-expression profile in eosinophilic esophagitis

Ablation of type I hypersensitivity in experimental allergic conjunctivitis by eotaxin-1/CCR3 blockade

The immune response is regulated, in part, by effector cells whose activation requires multiple signals. For example, T cells require signals emanating from the T cell antigen receptor and co-stimulatory molecules for full activation. Here, we present evidence indicating that IgE-mediated hypersensitivity reactions in vivo also require cognate signals to activate mast cells. Immediate hypersensitivity reactions in the conjunctiva are ablated in mice deficient in eotaxin-1, despite normal numbers of tissue mast cells and levels of IgE. To further define the co-stimulatory signals mediated by chemokine receptor 3 (CCR3), an eotaxin-1 receptor, effects of CCR3 blockade were tested with an allergic conjunctivitis model and in ex vivo isolated connective tissue-type mast cells. Our results show that CCR3 blockade significantly suppresses allergen-mediated hypersensitivity reactions as well as IgE-mediated mast cell degranulation. We propose that a co-stimulatory axis by CCR3, mainly stimulated by eotaxin-1, is pivotal in mast cell-mediated hypersensitivity reactions.

Biology of the eosinophil

In this review, we aim to put in perspective the biology of a multifunctional leukocyte, the eosinophil, by placing it in the context of innate and adaptive immune responses. Eosinophils have a unique contribution in initiating inflammatory and adaptive responses, due to their bidirectional interactions with dendritic cells and T cells, as well as their large panel of secreted cytokines and soluble mediators. The mechanisms and consequences of eosinophil responses in experimental inflammatory models and human diseases are discussed.

Intestinal macrophage/epithelial cell-derived CCL11/eotaxin-1 mediates eosinophil recruitment and function in pediatric ulcerative colitis

Clinical studies have demonstrated a link between the eosinophil-selective chemokines, eotaxins (eotaxin-1/CCL11 and eotaxin-2/CCL24), eosinophils, and the inflammatory bowel diseases, Crohn's disease and ulcerative colitis (UC). However, the cellular source and individual contribution of the eotaxins to colonic eosinophilic accumulation in inflammatory bowel diseases remain unclear. In this study we demonstrate, by gene array and quantitative PCR, elevated levels of eotaxin-1 mRNA in the rectosigmoid colon of pediatric UC patients. We show that elevated levels of eotaxin-1 mRNA positively correlated with rectosigmoid eosinophil numbers. Further, colonic eosinophils appeared to be degranulating, and the levels positively correlated with disease severity. Using the dextran sodium sulfate (DSS)-induced intestinal epithelial injury model, we show that DSS treatment of mice strongly induced colonic eotaxin-1 and eotaxin-2 expression and eosinophil levels. Analysis of eosinophil-deficient mice defined an effector role for eosinophils in disease pathology. DSS treatment of eotaxin-2(-/-) and eotaxin-1/2(-/-) mice demonstrated that eosinophil recruitment was dependent on eotaxin-1. In situ and immunofluorescence analysis-identified eotaxin-1 expression was restricted to intestinal F4/80(+)CD11b(+) macrophages in DSS-induced epithelial injury and to CD68(+) intestinal macrophages and the basolateral compartment of intestinal epithelial cells in pediatric UC. These data demonstrate that intestinal macrophage and epithelial cell-derived eotaxin-1 plays a critical role in the regulation of eosinophil recruitment in colonic eosinophilic disease such as pediatric UC and provides a basis for targeting the eosinophil/eotaxin-1 axis in UC.

Eosinophilic esophagitis

Eosinophilic esophagitis (EoE) is a disease based on a clinicopathologic diagnosis that involves a localized eosinophilic inflammation of the esophagus. A significant increase in the diagnosis of pediatric EoE has occurred over the past 10 years not only due to a greater recognition of the disease among gastroenterologists, allergists, and pathologists but also secondary to an increased incidence of the disease. EoE is defined by the presence of 15 or more esophageal eosinophils per high-power field isolated to the esophagus associated with clinical symptoms that do not respond to acid suppression therapy. Although the exact mechanism of EoE is unknown, food allergens are thought to have an important role. Effective treatment options include dietary restrictions and various steroid formulations.

Moving targets: cell migration inhibitors as new anti-inflammatory therapies

The pharmaceutical industry has targeted various types of molecules to subdue inflammatory diseases. Drugs that disrupt cell migration appear particularly promising in clinical trials and in many animal models of inflammatory disease. Cell migration inhibitors not only interfere with migration of cells to a tissue, but also can affect other necessary processes such as mediator release and angiogenesis. However, the question is whether drugs that target adhesion molecules or chemoattractant receptors will prove superior to drugs that target other molecular types. This review proclaims the virtues of targeting cell migration-related molecules for development of new anti-inflammatory and anti-tumor based drugs. It is likely that cell migration inhibitors will transform the way in which many human inflammatory diseases and cancers are treated.

Allergy and eosinophil-associated gastrointestinal disorders (EGID)

Eosinophil-associated gastrointestinal disorders (EGIDs) are characterized by an inappropriate accumulation of eosinophils within the gastrointestinal tract. The underlying etiology and pathophysiology that lead to the development of EGID are far from elucidated. However, there is growing evidence to support the role of aeroallergens and food allergens in the pathogenesis of these disorders. Recent advances have highlighted the role of Th2-driven cytokines in the development of EGID, and clinical studies have verified that children and adults with EGID often have positive skin testing to food allergens. The most common form of EGID, eosinophilic esophagitis (EE), has garnered intense investigation following an increased recognition over the past decade. Recently, there have been several important studies providing insight into both the cellular mechanisms governing EE and clinical therapies directed toward the treatment of EE. In the article herein, we will review the most recent scientific advances influencing our understanding of EGID with special emphasis on the role of allergens in the pathogenesis of EGID.

Treatment with topical steroids downregulates IL-5, eotaxin-1/CCL11, and eotaxin-3/CCL26 gene expression in eosinophilic esophagitis

OBJECTIVES

Our aim was to evaluate the changes induced by topical steroid treatment to the esophageal epithelial inflammatory eosinophilic and T-cell infiltrate and to IL-5, eotaxin-1/CCL11, and eotaxin-3/CCL26 esophageal gene expression levels in patients with eosinophilic esophagitis (EE).

METHODS

Esophageal biopsies were taken from eight adult patients at the moment of diagnosis and after 3-month treatment with fluticasone propionate. Eosinophils, CD8, and CD4 T cells were examined by immunohistochemistry. IL-5, eotaxin-1/CCL11, and eotaxin-3/CCL26 gene expression levels were measured by real-time PCR. Eight control samples were also analyzed.

RESULTS

A significant decrease in the eosinophil infiltrate and in CD8(+) T-cell density was observed in the esophageal epithelium from the patients upon steroid treatment. IL-5 was not detected in control samples, and expression levels were variably downregulated after treatment in six of the patients. Gene expression of eotaxin-1/CCL11 showed relevant downregulation in four cases and a modest twofold decrease in three of the patients studied. Mean CCL11 expression values upon steroid treatment were similar to control samples (19.4 +/- 28.6 vs 8.42 +/- 5, P= 0.7). Eotaxin-3/CCL26 gene expression levels were significantly increased in EE. Although they were significantly downregulated upon steroid treatment, control expression levels were not reached in any of the cases analyzed (580.9 +/- 943.9 vs 1.45 +/- 1.0, P= 0.001).

CONCLUSIONS

Our results confirm that eotaxin-3/CCL26 is significantly increased in EE esophageal samples. However, the individual analysis of IL-5, CCL11, and CCL26 expression data suggests that several cytokines and chemokines could participate in the physiopathology of EE in humans.

Eosinophilic oesophagitis and other non-reflux inflammatory conditions of the oesophagus: diagnostic imaging and management

Non-reflux inflammatory conditions of the oesophagus are at present rarely encountered in routine clinical practice. However there has been a recent increase in their diagnosis notably due to heightened awareness of their existence and because of the emergence of a number of immunological diseases and deficiencies. Of all the non-reflux conditions, most interest and literature is emerging on the natural history, pathophysiology, endoscopic pattern and management of eosinophilic oesophagitis. This condition, which until five years ago was unknown to most physicians has now been studied worldwide and although the true prevalence remains unclear, the incidence is increasing annually. In this paper we discuss diagnostic imaging and management of non-reflux inflammatory disorders of the oesophagus with particular reference to eosinophilic oesophagitis and Crohn's disease, both conditions of probable over active immunology, to other conditions associated with immune deficiency such as infective oesophagitis (candida, CMV, HSV, HIV) and tuberculous oesophagitis, as well as drug induced oesophageal injury.

2007 E. Mead Johnson award: scientific pursuit of the allergy problem

My research has focused on elucidating the allergy problem over the past two decades. The primary approach has been to uncover critical mechanisms of allergic inflammation, with particular focus on eosinophils, a hallmark cellular constituent of allergic responses. Molecular processes that bridge T helper cell type 2 (TH2) immunity with eosinophilia and key checkpoints for regulating eosinophilia have been uncovered. Notably, interleukin (IL)-5 (derived from TH2 cells) has been identified as the chief hematopoietin responsible for eosinophil expansion in the circulation. Pathways for selective eosinophil mobilization from the blood stream to the tissue have been uncovered by defining the role of the eotaxin subfamily of chemokines in eosinophil chemoattraction and activation. Finally, TH2 cell derived IL-4 and IL-13 have been defined as chief inducers of the eotaxins, and upstream orchestrators of eosinophilic inflammation. These translational studies have formulated novel therapeutic strategies (currently being tested) for a variety of eosinophilic conditions, with particular attention on hypereosinophilic syndromes and eosinophil-associated gastrointestinal disorders such as eosinophilic esophagitis.

Periostin facilitates eosinophil tissue infiltration in allergic lung and esophageal responses

Periostin is an extracellular matrix protein that has been primarily studied in the context of the heart, where it has been shown to promote cardiac repair and remodeling. In this study, we focused on the role of periostin in an allergic eosinophilic inflammatory disease (eosinophilic esophagitis (EE)) known to involve extensive tissue remodeling. Periostin was indeed markedly overexpressed (35-fold) in the esophagus of EE patients, particularly in the papillae, compared with control individuals. Periostin expression was downstream from transforming growth factor-beta and interleukin-13, as these cytokines were elevated in EE esophageal samples and markedly induced periostin production by primary esophageal fibroblasts (107- and 295-fold, respectively, at 10 ng ml(-1)). A functional role for periostin in eliciting esophageal eosinophilia was demonstrated, as periostin-null mice had a specific defect in allergen-induced eosinophil recruitment to the lungs and esophagus (66 and 72% decrease, respectively). Mechanistic analyses revealed that periostin increased (5.8-fold) eosinophil adhesion to fibronectin. As such, these findings extend the involvement of periostin to esophagitis and uncover a novel role for periostin in directly regulating leukocyte (eosinophil) accumulation in T helper type 2-associated mucosal inflammation in both mice and humans.

Eosinophilic oesophagitis: a common cause of dysphagia in young adults?

Eosinophilic oesophagitis (EO) is an increasingly recognised chronic, relapsing inflammatory condition of the oesophagus. There has been a mini-epidemic of EO in the last decade. The incidence of this condition is higher in children and is commoner in males. There is either a family or personal history of atopic conditions present in a significant number of patients and can also be familial in up to 10%. The classical symptom in an adult is chronic, intermittent solid-food dysphagia and food impaction, often necessitating emergency endoscopic removal. Despite the history of dysphagia for a number of years, patients remain well with no weight loss, which can mislead clinicians to diagnose a functional problem with a resulting delay in the diagnosis. There are various endoscopic features of EO; commonly multiple rings and linear furrows, though these can be subtle and the mucosa may be macroscopically normal. The hallmark of this condition is the histological presence of > or =15 eosinophils/high power field (HPF) in the oesophageal mucosa. Therapeutic options include avoidance of dietary allergens, topical or systemic steroids, Montelukast, Mepolizumab (anti-IL-5 antibody) and endoscopic dilation of strictures unresponsive to medical therapy.

Idiopathic eosinophilic gastrointestinal diseases in adults

This review focuses on the latest cognitions, diagnosis and treatment strategies of the three main representatives of the eosinophilic gastrointestinal disorders (EGID): idiopathic eosinophilic oesophagitis (EE), idiopathic eosinophilic gastroenteritis (EGE) and idiopathic hypereosinophilic syndromes (HES) with gastrointestinal involvement. These disorders share important similarities: their origin is unknown and their pathogenesis is due to a histological inflammatory response characterised by eosinophilic tissue infiltration. In spite of these parallels, the courses and prognoses of the diseases differ radically: EE is restricted to the oesophagus, and though it may significantly decrease the patient's quality of life, it has a favourable long-term prognosis. In EGE, the inflammatory process involves several segments of the gastrointestinal tract but this chronic inflammation may also be considered a benign disorder. In contrast, HES is primarily a multisystem disorder that may involve several organs, including the digestive tract, and often has a fatal outcome.

Eosinophilic esophagitis in adults

Eosinophilic esophagitis in adults is a disease characterized by eosinophilic infiltration of the esophageal mucosa and symptoms of long-standing solid food dysphagia and food impactions. First described in 1978, this syndrome is being recognized increasingly in the developed world, with multiple case series reported from the United States, Europe, and Australia during the past decade. Diagnosis requires the presence of greater than or equal to 15 eosinophils/high-power field on esophageal biopsies. Successful treatment in adults has been reported with the use of systemic and topical swallowed steroids. Endoscopic treatment has been associated with increased an risk for tears and perforations.

Functional gastrointestinal disorders and the potential role of eosinophils

The eosinophil-mast cell-neural pathway may be important in the pathophysiology of functional gastrointestinal disorders characterized by unexplained abdominal pain, disordered defecation, or meal-related discomfort. There is evidence that duodenal eosinophils are increased in functional dyspepsia, whereas mast cells are increased in the lower gut in irritable bowel syndrome, directly supporting a role for a hypersensitivity-type reaction in these disorders. The trigger may be a pathogen, food, or other allergen in the gut mucosa. This trigger may evoke eosinophils, mast cells, and other components to cascade to up-regulate serotonin release, with modulation of the enteric and central nervous systems, creating a vicious cycle. If correct, this theory suggests treatment should specifically target the eosinophil-mast cell pathway.

Clinical, pathologic, and molecular characterization of familial eosinophilic esophagitis compared with sporadic cases

BACKGROUND & AIMS

Eosinophilic esophagitis (EE) occurs in families.

METHODS

Record review confirmed patient kinship and provided clinical information. Slide review confirmed the diagnosis (threshold peak number > or = 24 eosinophils/high-power field).

RESULTS

Fifty-nine members (41 males, 18 females) of 26 families were 3 months to 47 years of age (mean age, 10.3 y) at diagnosis. The only recorded race was Caucasian. In 4 families a parent of an affected male had EE. The most common complaint at diagnosis was dysphagia (68% of patients). Endoscopy showed esophageal mucosal furrows (93% of patients) and exudates (44%). Fifty-one percent had asthma. Skin prick tests to food and aeroallergens were positive in 76% and 71%, respectively. Familial EE characteristics (clinical, endoscopic, pathologic, and global esophageal transcript expression profile analysis) were similar to sporadic EE, except among patients with mucosal furrows: familial patients had lower peak eosinophil counts in the distal esophagus (P = .03) compared with sporadic patients. The basic characteristics of EE (eg, eosinophil levels, rate of atopy) did not vary with patient age. By using genome-wide microarray analysis, no significant differences (P < .05, false-discovery rate) were observed between familial and sporadic EE. Among all patients, chest pain was more common in females (P = .02), and thickened mucosa was more common in males (P = .006).

CONCLUSIONS

These data support a familial pattern of inheritance of EE and a pathogenesis shared with sporadic EE. EE should be considered in symptomatic family members of patients who have EE.

Idiopathic eosinophilic disorders of the gastrointestinal tract in children

Over the last decade, eosinophilic gastrointestinal diseases have emerged as increasingly recognised diseases affecting both adults and children. While the exact morbidity is uncertain, it has become evident that they carry a significant cost to affected patients. Recent investigations shed light on basic mechanisms of eosinophilic recruitment and inflammation, and suggest a critical role for Th2 cytokines, such as eotaxin, and allergen exposure in their pathogenesis. Eosinophilic oesophagitis (EO) is the best characterised of these diseases, and improved understanding of its basic biology stimulated development of new treatment regimens. Current evidence supports the use of elemental diets and systemic or topical corticosteroids to treat EO. A major clinical problem is the fact that most patients relapse when medical treatment is discontinued, thus making nutritional management an attractive long term option. Many areas remain unanswered in the management of patients with EGIDs, including identification of optimal treatment protocol, development of appropriate non-invasive monitoring, and choice of appropriate therapeutic endpoints.

Eosinophilic esophagitis in children: clinical manifestations

During the past decade, the increasing number of recognized cases of eosinophilic esophagitis in children and adults has resulted in a dramatic expansion of the medical literature surrounding it. Clinical and basic research has contributed to a better, but still incomplete, body of knowledge regarding its clinical and histologic manifestations, as well as its immunologic and genetic pathogenesis. This article provides a broad framework for recognizing the remarkable variety of clinical manifestations of eosinophilic esophagitis in children, which must be considered as part of the differential diagnosis in many different clinical situations.

General laboratory diagnostics of eosinophilic GI diseases

Eosinophils and gastrointestinal tract interact in an intimate and enigmatic relationship. Under inflammatory conditions, eosinophil infiltration in the gastrointestinal tract is a common feature of numerous eosinophilic gastrointestinal disorders (EGIDs). EGIDs are disorders, for which the diagnosis is relatively difficult. Nevertheless, some common laboratory techniques are currently used for their diagnosis and disease monitoring. Besides eosinophils, mast cells and T cells have also been suggested to play a role in the pathogenesis of these disorders. Here, we review the pathogenesis and common laboratory approaches applied for their diagnosis, in particular eosinophil and mast cell markers.

Eosinophils and allergic diseases of the gastrointestinal tract

The association between increased tissue eosinophilia and allergic disease is particularly striking in the case of the gastrointestinal tract. About 80% of individuals with eosinophilic gastrointestinal disorders (EGIDs) are atopic, while half of the patients with gastrointestinal allergy show tissue eosinophilia. The function of eosinophils in gastrointestinal allergic disorders is unclear; however, a proinflammatory action is most likely. Cytokines (interleukins 5 and 3, granulocyte-monocyte colony-stimulating factor) and chemokines (eotaxin, RANTES, etc.) released by Th2 lymphocytes, mast cells and other tissue cells have been identified as major regulators of eosinophil chemotaxis and activation, but a convincing mechanism by which eosinophils are activated in an allergen-dependent manner is still lacking. The diagnostic approach comprises both histological and laboratory methods to assess eosinophilia and eosinophil activation, as well as tools to assess the allergic disease while excluding other gastrointestinal diseases such as food intolerances, infections and tumours. Treatment of allergic EGIDs includes elimination or elemental diets and drug therapy using classical anti-allergic agents such as topical corticosteroids and new approaches such as LTD4 receptor antagonists or antibodies against IL-5 or eotaxin.

Eosinophilic esophagitis: a prevalent disease in the United States that affects all age groups

BACKGROUND & AIMS

Most reports on eosinophilic esophagitis (EE) are limited to small series from single institutions. This study describes features of EE in a broader population.

METHODS

A national pathology database (Caris Diagnostics, Irving, TX) was used to identify EE cases from a cohort of upper endoscopies. Slides from potential cases were reviewed by pathologists. Study inclusion required a mean of (1) 20 eosinophils or more in 5 high-power fields, or (2) 30 eosinophils in 2-4 high-power fields. Endoscopists provided demographic and clinical information.

RESULTS

There were 363 cases identified from 74,162 patients and 26 states. EE had a male predominance (odds ratio, 3.0; 95% confidence interval, 2.4-3.8). Ages ranged from 1 to 98 years, including 42 children and 321 adults. The most common endoscopy indications in adults were dysphagia (70.1%) and gastroesophageal reflux disease (GERD)/heartburn (27.1%). Children most frequently reported GERD/heartburn (38.1%) and abdominal pain/dyspepsia (31.0%). A total of 25.1% of cases had a peak mucosal eosinophil count of 20-59, 29.2% had a peak mucosal eosinophil count of 60-100, and 45.7% had a peak mucosal eosinophil count of more than 100. There was no difference in the peak counts between age groups or sexes, but patients with dysphagia had higher counts (P < .001). The prevalence of EE increased during the study period (P < .001).

CONCLUSIONS

EE is a national disease found in all age groups, more frequently in males. Dysphagia and GERD symptoms are common indications for endoscopy. The degree of eosinophilic infiltration is high throughout all ages and may be related to patients' symptoms. Our series highlights important elements of this disease, the prevalence and/or recognition of which is increasing.

Oesophagitis in children: reflux or allergy?

The prevalence of eosinophilic oesophagitis appears to be increasing in many countries, sometimes rapidly, although this may be partly due to increased disease recognition. Histological methods of assessment and diagnostic criteria vary considerably between major clinical centres. Oesophagitis with over 20 intraepithelial eosinophils per high power field is more likely to be due to allergy than gastro-oesophageal reflux induced acid-peptic mucosal injury. Typical eosinophilic oesophagitis shows involvement of the entire oesophagus, with basal cell proliferation occupying more than 50% of the thickness of the surface epithelium, and high numbers of intraepithelial eosinophils, sometimes concentrated on the surface or as contiguous clusters. Ulceration and prominent neutrophils are atypical and should suggest an alternative or co-existent disease. On endoscopy, the oesophagus may display the typical 'corrugated' mucosal appearance. Clinically, dysphagia or food impaction are the most characteristic symptoms. There is a strong association with other atopic diseases, especially asthma and eczema. To date no evidence has emerged of an increased malignancy risk. Patients with eosinophilic oesophagitis typically fail to respond to acid suppressive medications but respond well to either elemental/elimination diets or aerosolised swallowed corticosteroids. Long-term uncontrolled oesophageal eosinophilic inflammation may lead to progressive subepithelial fibrosis, potentially resulting in strictures or oesophageal narrowing.

Clinical and pathological features of eosinophilic oesophagitis: a review

Eosinophilic oesophagitis (EOE) is a newly described clinicopathological entity that is being diagnosed with increasing frequency both in children and in adults. It is presumed to be an atopic disease involving both immediate and delayed-type hypersensitivity to inhaled and ingested allergens. Because of the reflux-type symptomatology, it is commonly misdiagnosed and treated as severe gastro-oesophageal reflux disease (GORD) before an appropriate diagnosis is made. Pathologically, EOE is an inflammatory disorder with a predominantly eosinophilic infiltrate that is unresponsive to acid suppression therapy. The diagnosis of this disease requires histological confirmation with oesophageal biopsy specimens showing an intense eosinophilic infiltration. Although precise criteria or a specific cutoff point for the diagnosis of eosinophilic oesophagitis have not been established, many authors suggest that one high-power field with >20 eosinophils or multiple high-power fields with >15 eosinophils, together with clinical and endoscopic findings, should be sufficient for diagnosis. Recognition of EOE and differentiation from GORD are important, since allergen elimination or anti-inflammatory therapy appears to be more effective than acid suppression in these patients. This review focuses on clinicopathological features and diagnosis of EOE in adults and children.

Eosinophilic esophagitis: management and pharmacotherapy

Eosinophilic esophagitis represents the most debated disease of the last 10 years, too often speculated or overestimated and certainly well known and examined. The aim of this study was to summarize the recent therapeutic trends in order to show persistent doubts regarding several debated therapies. The study combined the most recent international literature and the authors' daily experience to define the scope of the review, with limits caused by a lack of available randomized studies between dietetic and pharmacological treatment. It was concluded that eosinophilic esophagitis is an immunoallergic disease that is generally caused by identifiable food and environmental allergens although, in a minority of cases, the etiological trigger remains undetermined. Therapy usually fights the responsible agents, but sometimes they are not resolved. A need for more pathogenetically driven treatments is invoked.

Eosinophils: biological properties and role in health and disease

Eosinophils are pleiotropic multifunctional leukocytes involved in initiation and propagation of diverse inflammatory responses, as well as modulators of innate and adaptive immunity. In this review, the biology of eosinophils is summarized, focusing on transcriptional regulation of eosinophil differentiation, characterization of the growing properties of eosinophil granule proteins, surface proteins and pleiotropic mediators, and molecular mechanisms of eosinophil degranulation. New views on the role of eosinophils in homeostatic function are examined, including developmental biology and innate and adaptive immunity (as well as their interaction with mast cells and T cells) and their proposed role in disease processes including infections, asthma, and gastrointestinal disorders. Finally, strategies for targeted therapeutic intervention in eosinophil-mediated mucosal diseases are conceptualized.

[Eosinophilic esophagitis : a cause of dysphagia]

BACKGROUND

Eosinophilic esophagitis (EE) is a chronic, interleukin-5-driven inflammatory disease of the esophagus, causing dysphagia and esophageal food impactions. We analyzed the diagnostic results of patients with suspected or proven EE and in this article discuss the relevant aspects of this disease.

PATIENTS AND METHODS

Sixteen patients suffering from dysphagia or recurrent esophageal food impactions underwent rigid esophagoscopy to exclude EE. In six patients, 24-h pH monitoring was performed to exclude laryngopharyngeal reflux (LPR).

RESULTS

EE was diagnosed in only one patient, a boy with a history of peanut allergy and recurrent esophageal food impactions. In six patients, histological examination of biopsies revealed reflux esophagitis indicating gastroesophageal reflux disease (GERD). Using 24-h pH monitoring, LPR was diagnosed in four of six patients.

CONCLUSIONS

Even in patients presenting with typical symptoms of EE, this disease is rarely found. However, in male patients with asthma, allergies, or a history of recurrent esophageal food impactions, EE must be excluded. The most important differential diagnoses of EE are GERD and LPR.

Computed tomographic scan-diagnosed chronic obstructive pulmonary disease-emphysema: eotaxin-1 is associated with bronchodilator response and extent of emphysema

BACKGROUND

Bronchodilator responses are a hallmark of asthma and a subset of chronic obstructive pulmonary disease (COPD). We evaluated subjects with COPD and computed tomographic (CT) scan evidence of emphysema to determine the biomarker profile associated with a bronchodilator response.

OBJECTIVE

We investigated whether subjects with COPD and a bronchodilator response had increased levels of bronchoalveolar lavage (BAL) fluid eosinophil biomarkers, T(H)2 cytokines, CC chemokines, and serum allergen-specific IgE.

METHODS

All patients with COPD and control subjects (n = 31) had chest CT scans to detect emphysema and subsequent pulmonary function studies, BAL for biomarkers, and serum IgE measurements.

RESULTS

CT scan score, FEV(1), carbon monoxide single-breath diffusion capacity, and BAL fluid neutrophil biomarker levels were similar in subjects with COPD who had or did not have a bronchodilator response of greater than 12%. In contrast, levels of BAL fluid eosinophil biomarkers (eosinophil cationic protein [ECP] and eotaxin-1) were greater in patients with COPD with a bronchodilator response, whereas T(H)2 cytokines were not detectable in any patients with COPD. BAL fluid ECP and eotaxin-1 levels correlated with CT scan extent of emphysema. Immunostaining of COPD lung sections from a separate cohort of subjects with COPD and healthy subjects demonstrated epithelial expression of eotaxin-1 but no lung expression of IL-4 or IL-5.

CONCLUSION

Subjects with COPD diagnosed on the basis of the presence of emphysema on CT scan who have a bronchodilator response have increased levels of BAL ECP and eotaxin-1 but not T(H)2 cytokines.

CLINICAL IMPLICATIONS

Eosinophil biomarkers (ECP-1 and eotaxin-1) might identify a subset of subjects with COPD with emphysema on CT scans who have a bronchodilator response and an increased extent of emphysema on CT scanning.

IL-13 involvement in eosinophilic esophagitis: transcriptome analysis and reversibility with glucocorticoids

BACKGROUND

Eosinophilic esophagitis (EE) is an emerging worldwide disease that mimics gastroesophageal reflux disease. Early studies have established that esophageal eosinophilia occurs in association with T(H)2 allergic responses, and we recently identified an EE-specific esophageal transcriptome that included eotaxin-3.

OBJECTIVE

We sought to determine the mechanism by which this T(H)2 response leads to EE.

METHODS

Real-time PCR and microarray analysis were performed on RNA extracted from esophageal biopsy specimens and primary esophageal epithelial cell cultures stimulated with IL-13 (0-100 ng/mL). Transient transfections in esophageal cell lines were performed with plasmids containing the luciferase gene driven by eotaxin-3 promoter fragments and modified forms of signal transducer and activator of transcription 6.

RESULTS

The IL-13 mRNA level was markedly increased (16-fold) in esophageal biopsy specimens from patients with EE compared with those from healthy individuals. Furthermore, IL-13 treatment of primary esophageal epithelial cells was sufficient to induce a global-expression transcript profile that remarkably overlapped with the EE-specific esophageal transcriptome. In addition, esophageal epithelial cells markedly produce eotaxin-3 after IL-13 stimulation through a transcriptional mechanism dependent on signal transducer and activator of transcription 6. Lastly, increased IL-13 mRNA levels and the EE transcriptome were largely reversible with glucocorticoid treatment in vivo.

CONCLUSIONS

Taken together, we propose that the pathogenesis of EE is mediated by an IL-13-stimulated keratinocyte-derived transcriptome that is largely reversible with corticosteroid treatment. Furthermore, we identify an in vivo IL-13-induced transcriptome that has potential utility for target assessment after anti-IL-13 therapeutics.

CLINICAL IMPLICATIONS

IL-13-induced pathways and genes are fundamental processes in the cause and manifestations of EE; as such, therapeutic agents that interfere with IL-13 might be particularly useful for disease treatment.

Eosinophilic esophagitis in children: clinical manifestations

During the past decade, the increasing number of recognized cases of eosinophilic esophagitis in children and adults has resulted in a dramatic expansion of the medical literature surrounding it. Clinical and basic research has contributed to a better, but still incomplete, body of knowledge regarding its clinical and histologic manifestations, as well as its immunologic and genetic pathogenesis. This article provides a broad framework for recognizing the remarkable variety of clinical manifestations of eosinophilic esophagitis in children, which must be considered as part of the differential diagnosis in many different clinical situations.

Eosinophilic esophagitis: association with allergic disorders

Atopy has been linked to eosinophilic gastrointestinal disorders because of the role eosinophils play in atopic disorders. It has also been found that these disorders coexist. The goal of this article is to take a step back, and considering only eosinophilic esophagitis, attempt to determine from the available body of clinical and research literature: (1) Is the coexistence of these disorders attributable to a preconceived bias? If so, what is the source of the bias and how can it be removed? (2) Is there a cause and effect relationship? If so, can this relationship be harnessed for diagnostic and therapeutic modalities?

Translational research on the pathogenesis of eosinophilic esophagitis

Eosinophilic esophagitis (EE) is an inflammatory disease of the esophagus characterized by eosinophilic infiltration of the esophageal epithelium. EE is a relatively new disease from clinical and research standpoints. A recent surge in basic and translational studies has emerged to understand its pathogenesis since its recognition as a separate entity from acid-induced gastroesophageal reflux disease in 1995. Our understanding of this disease is still limited, however. In this article, available evidence from translational studies on EE is discussed, focusing on the allergic nature of the disease and highlighting the role of various inflammatory cells found in the esophagus of patients who have EE. Esophageal remodeling in EE is also discussed.

Origin, regulation and physiological function of intestinal oeosinophils

Oeosinophils are pleiotropic multi-functional leukocytes that are typically associated with the initiation and propagation of inflammatory responses, particularly helminth infection and allergic disease. However, expanding evidence supports a broader role for oeosinophils in homoeostatic function and organ development and modulation of local immune responses via interaction with other effector cells. In this review, the biology of oeosinophils in the healthy gut is summarised. In particular, the molecular steps involved in oeosinophil development and trafficking are described, with special attention to the important role of the transcription factor GATA-1, the oeosinophil-selective cytokine IL-5 and the eotaxin subfamily of chemokines. In addition, the regulation of oeosinophil survival by inhibitory and death receptors and the expanding role for oeosinophils in health and disease are reviewed.

Epidemiology and etiology of eosinophilic esophagitis

Eosinophilic esophagitis (EE) is an inflammatory disease of the esophagus characterized by eosinophilic infiltration of the esophageal mucosa. Symptoms of EE are variable, and include gastroesophageal reflux symptoms, abdominal pain, growth failure, and dysphagia. Dysphagia is a more common presentation in adults and older children. Serious complications of EE consisting of esophageal food impactions necessitating urgent endoscopic removal of the food and esophageal strictures requiring endoscopic balloon dilatations are also seen. The potential severity of these symptoms points to the importance of proper recognition and management of the disease, especially given that EE has become more prevalent over the past decade. In this article, available evidence on the epidemiology and etiology of EE is discussed.

Basic pathogenesis of eosinophilic esophagitis

Eosinophilic esophagitis (EE) is a newly recognized disease, which has largely been called idiopathic EE, emphasizing the poor understanding of its pathogenesis. EE is a severe disease of the esophagus characterized by an accumulation of eosinophils in the esophageal mucosa, and is highly associated with atopic disease. Nevertheless, the nomenclature "eosinophilic esophagitis" describes only the tip of the iceberg of a complex disorder, as the pathogenesis of EE involves multiple tissues, cell types, and genes, and derives from complex genetic and environmental factors. This article defines the fundamental knowledge available to date that characterizes the mechanisms by which certain etiological factors cause EE, reviewing human studies, murine models, and recent knowledge regarding the involvement of environmental, cellular, molecular, and genetic factors in the development of EE.

Histopathologic features of eosinophilic esophagitis

The pathology of eosinophilic esophagitis (EE) when fully developed in humans is highly characteristic and readily discriminated from the histology of the normal esophagus. The histologic alterations are not pathognomonic for any of the multiple causes of EE, and the correct diagnosis can be made only if the histology is correlated with clinical findings. The histology of the normal esophagus is reviewed and contrasted with the findings in EE. The characteristic findings in EE are illustrated. Selected research in humans and animal models pertinent to EE are briefly reviewed.

Esophageal dysmotility in patients who have eosinophilic esophagitis

The understanding of esophageal motility alterations in patients who have eosinophilic esophagitis (EE) is in its infancy despite the common presenting complaint of dysphagia. A diversity of motility disorders has been reported in patients who have EE including achalasia, diffuse esophageal spasm, nutcracker esophagus, and nonspecific motility alterations including high-amplitude esophageal body contractions, tertiary contractions, abnormalities in lower esophageal sphincter pressure, and other peristaltic problems. Some evidence suggests that treatment of EE will improve motility. Technological advances such as high-resolution manometry and combined manometry with impedance may provide new insight into more subtle motility abnormalities.

Noninvasive markers of eosinophilic esophagitis

There has been an increasing awareness and recognition of eosinophilic esophagitis (EE), a chronic condition with periods of exacerbation and remission, over the last decade. The complex pathophysiology of EE and eosinophil physiology provide several candidate biomarkers that could be studied on various noninvasively obtained body specimens. This article reviews several potential noninvasive biomarkers of EE.

Integrated approach to treatment of children and adults with eosinophilic esophagitis

Over the last decade, treatment plans for eosinophilic esophagitis included the use of elemental formula, elimination diets, systemic corticosteroids, and the gavage of aerosolized steroids. Except for one placebo-controlled blinded prospective study, most decision making has been based on retrospective or uncontrolled studies and clinical experience. In this article, three authors from diverse backgrounds combine their resources to propose treatment paths with justification based on their clinical experience and interpretation of the literature.

Demographic data and symptoms of eosinophilic esophagitis in adults

The clinical presentation of eosinophilic esophagitis in adults is varied but most often starts with some form of dysphagia. These patients often may be diagnosed incorrectly as having gastroesophageal reflux disease or functional disease, given the paucity of objective endoscopy and radiographic findings in some patients, even though symptoms often are severe and persistent. A careful history with attention to detail and a compilation of compatible characteristics is key to the clinician's diagnosing eosinophilic esophagitis in an adult.

Mechanisms of eosinophilia in the pathogenesis of hypereosinophilic disorders

The increased numbers of activated eosinophils in the blood and tissues that typically accompany hypereosinophilic disorders result from a variety of mechanisms. Exciting advances in translating discoveries achieved from mouse models and molecular strategies to the clinic have led to a flurry of new therapeutics specifically designed to target eosinophil-associated diseases. So far, this form of hypothesis testing in humans in vivo through pharmacology generally has supported the paradigms generated in vitro and in animal models, raising hopes that a spectrum of novel therapies soon may become available to help those who have eosinophil-associated diseases.