Quantification Of Eosinophils Research Articles

Quantification of eosinophils in the lower gastrointestinal tract of adults: a review of surgical specimens with normal histology from the Free State province, South Africa.

Eosinophils are normal residents of the gastrointestinal tract (GIT). They are noted in small numbers with significant variation between anatomic locations. An idiopathic increase of eosinophils is known as eosinophilic gastrointestinal disease (EGID). EGIDs are a heterologous group of disorders that produce a range of enteric and colonic syndromes. Their incidence has been increasing worldwide. Our study aimed to quantify eosinophils in each segment of the GIT in surgical specimens with normal histology to facilitate the histological diagnosis of EGID. Similarly, we aimed to describe the effect of race and gender on gastrointestinal eosinophil numbers. A retrospective, quantitative comparative study was performed. We assessed 360 surgical specimens with normal histology from the lower gastrointestinal tract of African and Caucasian adults from the Free State Province, South Africa. The number of eosinophils per mm² was counted. Overall, comparable eosinophil values were noted for both males and females, and African and Caucasian South Africans. However, Caucasians recorded a higher concentration of eosinophils in the appendix and the left colon. Eosinophils were most numerous in the lamina propria, with only small numbers present in the epithelium. Our results show that the South African population has similar eosinophil distribution trends to international studies. However, South Africans had far fewer eosinophils than Japanese and North American adults in each segment. Specific eosinophil reference ranges were formulated to quantify reference ranges of eosinophils in the lower GIT, allowing for the accurate diagnosis of EGIDs in our population in future.

Redefining Histological Cell Counts Using a Standardized Method: The Leuven Intestinal Counting Protocol.

The diagnosis of eosinophilic gastrointestinal diseases is largely based on mucosal eosinophil counts, but thresholds and normal ranges beyond the esophagus are debated, calling for much-needed methodological standardization. We aimed to develop a standardized workflow for duodenal cell quantification and estimate duodenal eosinophil and mast cell numbers in healthy controls. Software-based histological cell quantification using free-sized or fixed-sized regions was developed and applied to digitized hematoxylin and eosin (H&E)-stained slides from 58 individuals (healthy controls [HCs] and patients with functional dyspepsia). Intraclass correlation coefficients (ICCs) compared inter-rater reliability between software-based and microscopic quantification. Reproducibility of the software-based method was validated in an independent cohort of 37 control and functional dyspepsia subjects. Eosinophil identification on H&E staining was compared to immunohistochemistry (IHC). Normal eosinophil (H&E) and mast cell (cKit) ranges were determined in 70 adult HCs. Eosinophil quantification on digitized slides demonstrated excellent (ICC = 0.909) and significantly improved reproducibility over microscopic evaluation (ICC = 0.796, P = 0.0014), validated in an independent cohort (ICC = 0.910). Duodenal eosinophils were more abundant around crypts than in villi ( P < 0.0001), while counts were similar on matched H&E- and IHC-stained slides ( P = 0.55). Mean ± SD (95th percentile) duodenal eosinophils and mast cells in HC were 228.8/mm 2 ± 94.7 (402.8/mm 2 ) and 419.5/mm 2 ± 132.2 (707.6/mm 2 ), respectively. We developed and validated a standardized approach to duodenal histological cell quantification, generalizable to various mucosal cell types. Implementation of software-based quantification identified 400 eosinophils/mm 2 and 700 mast cells/mm 2 as thresholds for abnormal duodenal infiltration.

Multiple instance learning for eosinophil quantification of sinonasal histopathology images: A hierarchical determination on whole slide images.

We proposed a hierarchical framework including an unsupervised candidate image selection and a weakly supervised patch image detection based on multiple instance learning (MIL) to effectively estimate eosinophil quantities in tissue samples from whole slide images. MIL is an innovative approach that can help deal with the variability in cell distribution detection and enable automated eosinophil quantification from sinonasal histopathological images with a high degree of accuracy. The study lays the foundation for further research and development in the field of automated histopathological image analysis, and validation on more extensive and diverse datasets will contribute to real-world application.

Abstract 2352: Development of an AI-based algorithm to quantify eosinophils in H&amp;E images from colorectal cancer (CRC) tissue sections guided by biomarker staining using multiplex immunofluorescence imaging

Abstract Background: Eosinophils are innate immune granulocytes that migrate to areas of inflammation to combat against infection and disease. Best known for their detrimental role in asthma and allergic disorders, there is growing interest in the involvement of eosinophils in cancer. Eosinophils are routinely observed in the tumor microenvironment (TME) and, depending on the cancer type, have been shown to drive other immune cells to either suppress or promote tumor growth - In colorectal cancer (CRC), eosinophil infiltration into the TME has been linked to a favorable prognosis. However, the behavior of eosinophils and their effect on associated immune mediators in the TME remains poorly understood. Currently, eosinophils are primarily identified from H&amp;E stained tissue sections based on morphological features by a pathologist, but it can be challenging to reliably and efficiently identify all eosinophils based on morphology alone. Here, we present a novel image analysis workflow that established an AI-based cell classifier which can accurately quantify eosinophils in H&amp;E stained CRC tissue sections by leveraging biomarker staining of eosinophils using multiplex immunofluorescence (mIF) imaging in conjunction with the morphological characteristics of eosinophils observed by H&amp;E. Methods: CRC tissue sections were labeled with a 5plex panel of eosinophil-specific markers and imaged by mIF using the PhenoImager HT platform (Akoya). Biomarker fluorescence was then quenched, sections stained by H&amp;E, and reimaged using the PhenoImager. mIF and H&amp;E images were then imported into the HALO® platform for algorithm development. Halo AI cell classification of eosinophils was trained on the morphological features of eosinophil staining in H&amp;E images, guided by eosinophil-specific labeling in the 5plex mIF images. H&amp;E staining was also performed on a serial section of each specimen. Morphological identification of eosinophils in H&amp;E images was performed by a pathologist. Results: Correlation analysis was performed to evaluate the relationship, per high power field (HPF), between manual eosinophil counts by a pathologist and AI algorithm derived eosinophils counts. The results showed the two methods are highly correlated, demonstrating reliable algorithm performance. Conclusion: The AI-based eosinophil detection algorithm established here enables high-throughput analysis and quantification of eosinophils from H&amp;E stained CRC tissue specimens and facilitates morphology diagnosis. Citation Format: Arezoo Hanifi, Elizabeth Blain, James Hargrove, Jeff Lock, Nam Tran, Vladislav Chizhevsky, Qingyan Au. Development of an AI-based algorithm to quantify eosinophils in H&amp;E images from colorectal cancer (CRC) tissue sections guided by biomarker staining using multiplex immunofluorescence imaging [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 2352.

Metabolomics combined with network pharmacology reveals anti-asthmatic effects of Nepeta bracteata on allergic asthma rats

ObjectiveTo investigate the mechanisms that underlie the anti-asthmatic effects of Nepeta bracteata (DBJJ, Dabao Jingjie in Chinese) in rats by integrating metabolomics and network pharmacology. MethodsIn this study, the rat model of asthma was induced by ovalbumin (OVA), and the rats were treated with a decoction of N. bracteata. Pathological changes in lung tissue were observed, and the quantification of eosinophils (EOS) and white blood cells (WBC) in bronchoalveolar lavage fluid was performed. Furthermore, the serum levels of asthma-related factors induced by OVA were assessed. 1H NMR spectroscopy serum metabolomics method was utilized to identify differential metabolites and their associated metabolic pathways. UPLC-QE-MS/MS combined with network pharmacology was employed to predict the core targets and pathways of DBJJ in its action against asthma. The anti-asthmatic properties of DBJJ were investigated using an integrated approach of metabolomics and network pharmacology. The findings were validated through molecular docking and Western blotting analysis of the key targets. ResultsThe administration of DBJJ effectively alleviated OVA-induced lung histopathological changes and decreased the number of EOS and WBC in BALF. Additionally, DBJJ inhibited the OVA-induced elevation of TNF-α, IL-18, Ig-E, EOS, IL-1β, MDA, VEGF-A, and TGF-β1. A total of 21 biomarkers and 10 pathways were found by metabolomics analysis. A total of 29 compounds were identified by UPLC-QE-MS/MS, in which 13 active components were screened by oral availability and Caco-2 cell permeability, the 120 targets and 173 KEGG pathways were predicted. The integration of metabolomics and network pharmacological analysis revealed that DBJJ's main constituents, including ferulic acid and ursolic acid, exerted their effects on four targets, namely DAO and NOS2, as well as their associated metabolites and pathways. The active constituents of DBJJ demonstrated a high binding affinity towards DAO and NOS2. Furthermore, DBJJ was observed to decrease the protein expression and phosphorylation levels of NOS2, MAPK, and STAT3. ConclusionThe administration of DBJJ demonstrates notable anti-asthma properties in rats with allergic asthma. This effect can be attributed to the modulation of various targets, including NOS2, MAPK, and STAT3, by primary constituents such as ferulic acid and ursolic acid.

Confirmation of eosinophilic sialodochitis by terminal duct biopsy.

To analyse the histopathological features of eosinophilic sialodochitis by using terminal duct biopsy. Sixty-five patients with suspected eosinophilic sialodochitis and four with chronic obstructive sialadenitis were prospectively enrolled. Clinical features, laboratory tests and sialograms were comparatively analysed. Terminal duct biopsy of the parotid or submandibular glands was performed concomitantly with endoscopy-assisted duct dilatation to determine the histopathological features of eosinophilic sialodochitis. Based on eosinophil quantification, the samples of suspected patients were scored as 'definite', 'highly suspected' and 'negative' in 26 (40%), 15 (23.1%) and 24 (36.9%) cases, respectively. Gland types and peripheral blood eosinophil counts were significantly different among these three groups. The proportions of itching glands, mucus plug exudations and elevated immunoglobulin E levels were higher in the 'definite' group than in the other two groups; however, the intergroup differences were insignificant. The primary pathological features of eosinophilic sialodochitis were abundant eosinophils and lymphocytes infiltrated around the duct, degranulation of eosinophils, extensive fibrosis and scattered mastocytes. Periductal eosinophils were not found in cases of chronic obstructive sialadenitis. Our findings suggest that terminal duct biopsy is safe and valuable for the pathological confirmation of eosinophilic sialodochitis, and can be used simultaneously with endoscopy-assisted duct dilatation.

Multi-instance learning for eosinophil quantification of sinonasal histopathology images

Multi-instance learning for eosinophil quantification of sinonasal histopathology images

A mouse model of allergic conjunctivitis permitting tear eosinophil quantification

IntroductionAllergic conjunctivitis is an immune-mediated inflammatory disease of the conjunctiva that is induced by antigens. Allergic conjunctivitis can cause various symptoms such as ocular itching, hyperemia and edema. Developing experimental animal models that show clinical symptoms and methods for quantitative and objective evaluation is important for understanding allergic conjunctivitis. Therefore, this study aimed to develop an ovalbumin (OVA)-induced mouse model of allergic conjunctivitis and a useful method for evaluating symptoms of allergic conjunctivitis. MethodsICR mice were sensitized by an intraperitoneal injection of OVA in PBS containing alum on days 0 and 5. Subsequently, local sensitization was then performed once daily from days 14 to 28, by instilling OVA in PBS into the both eyes. Drug treatment was administered once daily from days 14 to 28. Mice were randomly assigned topical treatment groups: Group 1, 0.1% betamethasone; Group 2, 0.025% levocabastine; Group 3 PBS (control). ResultsMice showed marked eye scratching behavior, hyperemia, edema, infiltration of eosinophils into tears and increased antigen-specific immunoglobulin E antibody levels in tears and the serum. These symptoms were inhibited by instillation of levocabastine and betamethasone, which are used clinically for the treatment of allergic conjunctivitis. DiscussionThis method may be useful for evaluation of the symptoms of allergic conjunctivitis in experimental and clinical settings. In particular, the developed method, which measures the number of eosinophils in tears collected with phenol red threads, may enable the quantitative, objective, and noninvasive evaluation of the severity of allergic conjunctivitis.

Histological Identification and Quantification of Eosinophils and Ascites in Leghorn Chickens Treated with High Oral Concentrations of NaCl-Pilot Study.

The purpose of this pilot study was to determine the role played by eosinophils in NaCl poisoning and right cardiac hypertrophy (ascitic syndrome) in Leghorn chickens, as well as the histological findings in the central nervous system (CNS), liver, and kidney. Moreover, the hypertrophy of the right ventricle index (HRVI) as an indicator of ascites was evaluated. Male SPF Leghorn birds at 28 days of age were submitted to two experiments. Food and water (FW) experiment: birds were treated with food plus 3.3% NaCl for the next 27 days and 1% NaCl in their drinking water from days 22 to 27. Water experiment (W): birds were treated with 1% NaCl in their drinking water for 5 days. In both experiments, the chickens exhibited loss of appetite, diuresis, and watery, green diarrhea during treatment days; at 24–27 td-FW and experiment W, the birds showed nervous signology (prostration, running movements, tremors, and comatose state). In the leukogram at 28 td-FW, an increase (p < 0.05) in heterophiles and basophils was observed. CNS eosinophilia was not observed in birds intoxicated with NaCl, though they did present demyelination in the brain and spinal cord, hepatic degeneration, mesangial proliferative glomerulopathy, and acute proximal renotubular necrosis.

S1453 Systematic Collection of Biopsies and Quantification of Eosinophils in Multiple High-Power Fields Is Required for Diagnosis of Eosinophilic Gastritis and/or Duodenitis

S1453 Systematic Collection of Biopsies and Quantification of Eosinophils in Multiple High-Power Fields Is Required for Diagnosis of Eosinophilic Gastritis and/or Duodenitis

Prognostic assessment of different methods for eosinophils detection in oral tongue cancer

AbstractBackgroundTATE has been proposed as a prognostic factor in oral cancer staging; however, the controversial literature data limit its application in the routine diagnosis. The aim of this study was to evaluate the prognostic value of TATE in patients with oral tongue cancer. The second aim was to identify any difference in the methods of eosinophil quantification or in the cutoff values reported in literature.MethodsClinic‐pathological data of 204 patients treated at “Ospedali Riuniti” Hospital, Ancona, Italy, were collected. Evaluation of TATE was performed on hematoxylin‐and‐eosin‐stained slides and correlation with survival outcomes was evaluated. The number of eosinophils per square millimeter was evaluated by using two methods, namely density (TATE‐1) and classical (TATE‐2) methods. For each of the 2 methods tested, patients were stratified into two or three groups, according to the most used cutoff values reported in literature.ResultsRegardless of the method of eosinophil quantification or the cutoff values used, patients with high TATE had a significantly better disease‐specific survival. The density method (TATE‐1) showed a better predictive performance, in particular when applying a single cutoff of 67 eosinophils/mm2, two cutoffs of 10 and 100 eosinophils/mm2, or two cutoffs of 50 and 120 eosinophils/mm2.ConclusionThe evaluation of TATE is simple, cost‐effective, and easy to implement in daily practice with the aim of improving risk stratification of patients affected by oral tongue cancer. Results of prognostic performance analysis suggest using density (TATE‐1) method as the standard approach to evaluate TATE in future studies, enhancing replicability.

Validation of the diagnosis of eosinophilic esophagitis based on histopathology reports in Sweden.

BackgroundEosinophilic esophagitis (EoE) is a relatively new diagnosis, where until recently a specific international classification of disease code was missing. One way to identify patients with EoE is to use histopathology codes. We validated the clinicopathological EoE diagnosis based on histopathology reports and patient charts to establish these data sources as the basis for a nationwide EoE patient cohort.MethodsThrough the Epidemiology Strengthened by histoPathology Reports in Sweden (ESPRESSO) study, we randomly selected 165 patients from five Swedish health care regions with a histopathologic diagnosis of EoE. Patients were assigned a histopathology diagnosis of EoE if they had ≥15 eosinophils per high-power field or, in the absence of eosinophil quantification, the pathologist interpreted the biopsy as consistent with EoE. Patient charts were scrutinized to see if the other diagnostic criteria were fulfilled. Of the 131 received patient charts, 111 (85%) had sufficient information to be included in the study.ResultsOf the 111 validated patients, 99 had EoE, corresponding to a positive predictive value of 89% (95% confidence interval = 82–94%). Dysphagia was the most common symptom (n = 78, 70%), followed by food impaction (n = 64, 58%) and feeding difficulties (n = 37, 33%). Twelve patients had coexisting asthma (11%) and 16 allergic rhinitis (14%). Seventeen patients underwent esophageal dilatation (15%), of which seven had more than one dilatation. Ninety-seven (87%) patients had a proton-pump inhibitor treatment ≤2 years before or after the diagnosis. Forty-two patients (38%) had been prescribed inhalation steroids and 64 (58%) had undergone esophageal radiology.ConclusionHistopathology reports from the ESPRESSO cohort with esophageal eosinophilic inflammation are suggestive of EoE.

Validation of the diagnosis of eosinophilic esophagitis based on histopathology reports in Sweden

Background: Eosinophilic esophagitis (EoE) is a relatively new diagnosis, where until recently a specific international classification of disease code was missing. One way to identify patients with EoE is to use histopathology codes. We validated the clinicopathological EoE diagnosis based on histopathology reports and patient charts to establish these data sources as the basis for a nationwide EoE patient cohort.&#x0D; Methods: Through the Epidemiology Strengthened by histoPathology Reports in Sweden (ESPRESSO) study, we randomly selected 165 patients from five Swedish health care regions with a histopathologic diagnosis of EoE. Patients were assigned a histopathology diagnosis of EoE if they had ≥15 eosinophils per high-power field or, in the absence of eosinophil quantification, the pathologist interpreted the biopsy as consistent with EoE. Patient charts were scrutinized to see if the other diagnostic criteria were fulfilled. Of the 131 received patient charts, 111 (85%) had sufficient information to be included in the study.&#x0D; Results: Of the 111 validated patients, 99 had EoE, corresponding to a positive predictive value of 89% (95% confidence interval = 82–94%). Dysphagia was the most common symptom (n = 78, 70%), followed by food impaction (n = 64, 58%) and feeding difficulties (n = 37, 33%). Twelve patients had coexisting asthma (11%) and 16 allergic rhinitis (14%). Seventeen patients underwent esophageal dilatation (15%), of which seven had more than one dilatation. Ninety-seven (87%) patients had a proton-pump inhibitor treatment ≤2 years before or after the diagnosis. Forty-two patients (38%) had been prescribed inhalation steroids and 64 (58%) had undergone esophageal radiology.&#x0D; Conclusion: Histopathology reports from the ESPRESSO cohort with esophageal eosinophilic inflammation are suggestive of EoE.

Superior turbinate eosinophilia predicts olfactory decline in patients with chronic rhinosinusitis

BackgroundPredicting postoperative olfactory decline in patients with chronic rhinosinusitis (CRS) remains a considerable challenge. ObjectiveTo evaluate patterns of postoperative olfactory function in patients with CRS and explore potential predictors of postoperative olfactory decline. MethodsA total of 76 patients with CRS electing endoscopic sinus surgery (ESS) were enrolled in this prospective study. Olfaction was assessed with Sniffin’ Sticks preoperatively and 3 months postoperatively. Preoperative peripheral venous blood and superior turbinate at surgery were collected for eosinophil quantification. Olfactory cleft was evaluated by computed tomography and endoscopy. Postoperative olfactory decline was defined by a decrease in threshold-discrimination-identification (TDI) score more than 0 point. Multivariable logistic regression analysis was conducted to identify potential predictors associated with postoperative olfactory decline in TDI score. ResultsA total of 30.26% of patients with CRS (23/76) presented with olfactory decline 3 months post-ESS. Patients with CRS with olfactory decline showed significantly higher preoperative tissue eosinophils (P < .001), blood eosinophil count (P = .002), blood eosinophil percentage (P = .009), and preoperative TDI scores (P = .017) than patients with CRS without olfactory decline. After adjusting for patient demographics and comorbidities, the preoperative tissue eosinophilia was significantly associated with patients with CRS with postoperative olfactory decline (odds ratio = 1.103; P = .038). An absolute count of 23.5 eosinophils per high-power field in superior turbinate was the best predictor of olfactory decline with the highest area under the receiver operating characteristic curve of 0.901. ConclusionSuperior turbinate eosinophilia is highly associated with olfactory decline in patients with CRS 3 months after ESS.

Eosinophils in the gastrointestinal tract: how much is normal?

The normal density of eosinophils in the digestive mucosa of children has been rarely addressed despite being important to provide baseline counts for the diagnosis of eosinophilic gastrointestinal disorders (EGID). Histopathological criteria for EGID remain undefined and there has been little consistency of results in different populations. We aimed to establish the eosinophil density of the normal digestive mucosa in a paediatric population submitted to endoscopic procedures with normal histological features. Biopsies from endoscopies of 33 patients were evaluated. Quantification of eosinophils was performed manually. Review of the pathology reports confirmed absence of abnormality in the biopsy specimens. Counts were expressed in eosinophils per high power field and per mm2. Oesophagus (n = 33): eosinophils were uniformly absent in all biopsies. Stomach: counting was performed, separately, in the superficial and deep lamina propria of the fundus (n = 13), corpus (n = 13) and antrum (n = 16). Mean eosinophilic density was higher in the deep lamina propria. Small intestine: eosinophil counts revealed 18.1 ± 17.0, 14.4 ± 12.0, and 51.5 ± 35.3 in the lamina propria of the bulb (n = 13), D2 (n = 13), and ileum (n = 16), respectively. Large intestine: the highest peak count was observed in the caecum (125 mm2; n = 16) with a mean of 51.8 ± 33.5. The eosinophil counts were lower in the ascending (n = 16; 40.9 ± 27.4), transverse (n = 14; 34.3 ± 21.9), descending (n = 15; 40.0 ± 26.6), and sigmoid (n = 17; 25.8 ± 17.8) colon and in the rectum (n = 17; 13.9 ± 10.1). These data provide a baseline count and distribution of eosinophils in the gastrointestinal tract of paediatric patients with normal mucosa, thus expanding the scarce published data.

Repeatability of nasal allergen challenge results: Further validation of the allergic rhinitis clinical investigator collaborative protocols

BackgroundNasal allergen challenge (NAC) models have been used to study allergic rhinitis and new therapies. Symptoms and biological samples can be evaluated at time points after allergen exposure. ObjectiveTo verify protocol repeatability and adequate interval between allergen exposures. MethodsTen ragweed allergic participants were exposed to incrementally increasing dosages of ragweed allergen intranasally until they achieved a total nasal symptom score (TNSS) of 8 of 12 and a peak nasal inspiratory flow (PNIF) of 50% reduction or more from baseline. Three weeks later, participants were challenged with a cumulative dose equal to the sum of all the allergen doses received at screening. TNSS and PNIF were recorded at regular intervals, including a 24-hour assessment. A subsequent visit was conducted after a further 3 weeks. Nasal secretion samples were collected for cytokine and eosinophil quantification. ResultsNine participants completed all visits. TNSS and PNIF responses followed previous patterns, with an initial peak at 30 minutes followed by a gradual decline. Most participants reported similar patterns at both NAC visits, although some did not demonstrate the same phenotype at both visits. Some experienced a secondary symptom increase 24 hours after NAC. Eosinophil and cytokine sections followed a similar pattern at both NAC visits. ConclusionNAC is an adequate method for modeling AR in humans, demonstrating appropriate repeatability of symptoms, nasal mucosal eosinophil, and cytokines. The 24-hour time point, previously not studied in our model, may be beneficial in evaluation of long-acting medications. This three-week interval NAC model will be beneficial for studies in which before and after treatment comparisons are desired.

Value of an Additional Review for Eosinophil Quantification in Esophageal Biopsies

Eosinophilic esophagitis (EoE) requires a peak count of 15 eosinophils per high-power field (hpf). Herein, the peak eosinophil count specified by a pathologist was compared with the second review of a research assistant. Of 477 biopsies, 106 had a peak count between 1 and 14 eosinophils/hpf cited in the pathology report, and 23/106 (22%) had ≥15 eosinophils/hpf on second review. The pathology report detected potential EoE with 99% specificity, but 80% sensitivity. As such, an additional review of esophageal biopsies yields higher eosinophil counts in ∼5% of cases. We propose that biopsies with a count between 1 and 14 eosinophils/hpf require further investigation because ∼22% may yield a potential EoE diagnosis.

Fetal exposure to bisphenol A as a risk factor for the development of childhood asthma: an animal model study

BackgroundThe prevalence of asthma in industrialized countries has been increasing dramatically and asthma is now the most common chronic disease of children in the United States. The rapidity of the increase strongly suggests that changes in environmental exposures are the likely cause of this epidemic. Further, the early onset of allergic manifestations suggests that these exposures may act on the prenatal development of the immune system. We have focused on the potential effects of bisphenol A (BPA), a chemical pollutant with one of the largest productions, on the development of childhood asthma. We have reported that perinatal BPA exposure promotes the development of allergic asthma in a mouse model. The current study was designed to identify a critical period of BPA exposure and to begin elucidating the mechanisms for this susceptibility.MethodsFemale BALB/c mice received 10 micro g/ml BPA in their drinking water from one week before pregnancy until the end of the study. Some of the pups were transferred in the first 48 h of life from their BPA-loaded mother to an unexposed mother, or vice versa. Half of the pups were sensitized with a low dose of the experimental allergen ovalbumin (OVA), the rest received PBS as an unsensitized controls. On day 22, the pups were challenged by inhalations of ovalbumin or PBS followed by quantification of eosinophils in and hyperreactivity of their airways, major indicators of experimental asthma in this classical mouse model. Hepatic expression of two isoforms of UDP-glucuronosyltransferase (Ugt) was quantified by quantitative RT-PCR at various ages.ResultsPups exposed to BPA in utero and through breast milk, or in utero only, displayed an asthma phenotype in response to their "suboptimal" allergic sensitization, whereas, pups only exposed to BPA postnatally from breast milk, did not. The expression of Ugt2b1, an isoform related to BPA clearance in rats, was not detectable in mouse fetuses and newborn pups, but increased by day 5 and approached adult levels by day 25.ConclusionsPrenatal exposures that produce environmentally relevant burdens of BPA, followed by postnatal allergic sensitization and challenges, promote the development of experimental allergic asthma. Delayed expression of BPA-metabolizing enzymes may explain, at least in part, the enhanced fetal susceptibility to this common environmental contaminant.

46. Increased eosinophils and mast cells in the irritable bowel syndrome

Background Irritable bowel syndrome is a functional bowel disorder, the aetiopathogenesis of which has been poorly understood. It appears to be multifactorial and to involve altered gastrointestinal motor function, enhanced perception of visceral stimuli and psychosocial factors. Only a few studies have analysed the involvement of inflammatory cells in this condition. The aim of this study was to determine whether eosinophils and mast cells were increased in the colonic mucosa in irritable bowel syndrome compared to controls. Method Slides of 20 colonic biopsy materials of patients with irritable bowel syndrome who had endoscopically and histologically normal colonic mucosa were analysed. Twenty normal controls that had random colonic biopsies with macroscopic and histologic normal colonic mucosa and no organic or functional bowel disease were enrolled. Quantification of eosinophils and mast cells was performed on three non-overlapping fields of lamina propria at ×40 magnification. Eosinophil degranulation was semi-quantitatively estimated assessing the extent of free granules within the lamina propria. Results Among the total of 20 tests and 20 controls, the majority were females (75% and 65%, respectively). Diarrhoea predominant irritable bowel syndrome was the most common mode of presentation. Eosinophil number, degranulation and mast cell count were significantly high in colonic biopsies obtained from irritable bowel syndrome compared to control. Comment Elevated mast cells have already been reported in the colonic and ileal biopsies and there were a few proposals predicting the involvement of eosinophils in the pathogenesis of the irritable bowel syndrome. This study supports this finding and explains the possible neural – mast cell – eosinophil interaction in generating the symptoms of functional gastrointestinal disorders including irritable bowel syndrome.

Eosinophiluria is common among patients after ileal conduit surgery

Urinary eosinophils are used to screen for acute interstitial nephritis (AIN). Technologists in the Mayo Clinic Renal Laboratory observed that patients with urinary diversion surgeries frequently had an unusually high number of urinary eosinophils. Urine samples from three cohorts of patients were studied (n=20 each): (1) urinalysis samples with a "stoma" source indicating a previous ileal conduit surgery; (2) urine samples clinically submitted for eosinophil quantification; (3) randomly selected urinalysis samples with a minimum of 1-3 white cells per high-powered field. Urinary eosinophils were quantified after Hansel staining as the mean of independent counts by four blinded technologists. Eosinophils composed an average 19% of the urinary white cells in the stoma group, even though none had a clinical suspicion of AIN. In contrast, only 3.5% and 4.6% of the urinary white cells were eosinophils among patients with clinically-ordered eosinophiluria testing and in a random sample of patients with pyuria, respectively (p<0.001 for each group vs. the stoma patients). Importantly, 90% (18 out of 20) of the stoma patients had >5% eosinophils, meeting the criterion for a positive test. Patients with a previous ileal conduit surgery have markedly elevated urinary eosinophils, far in excess of typical patients with pyuria or those with clinically-ordered eosinophiluria testing. Therefore, urinary eosinophils are not a useful screen for AIN in patients after ileal conduit surgery.