Increased expression of intercellular adhesion molecule-1 and mucosal adhesion molecule alpha4beta7 integrin in small intestinal mucosa of adult patients with food allergy

T and B Lymphocyte Transcriptional States Differentiate between Sensitized and Unsensitized Individuals in Alpha-Gal Syndrome

The mechanisms of pathogenesis driving alpha-gal syndrome (AGS) are not fully understood. Differences in immune gene expression between AGS individuals and non-allergic controls may illuminate molecular pathways and targets critical for AGS development. We performed immune expression profiling with RNA from the peripheral blood mononuclear cells (PBMCs) of seven controls, 15 AGS participants, and two participants sensitized but not allergic to alpha-gal using the NanoString nCounter PanCancer immune profiling panel, which includes 770 genes from 14 different cell types. The top differentially expressed genes (DEG) between AGS subjects and controls included transcription factors regulating immune gene expression, such as the NFκB pathway (NFKBIA, NFKB2, REL), antigen presentation molecules, type 2/allergic immune responses, itch, and allergic dermatitis. The differential expression of genes linked to T and B cell function was also identified, including transcription factor BCL-6, markers of antigen experience (CD44) and memory (CD27), chemokine receptors (CXCR3, CXCR6), and regulators of B-cell proliferation, cell cycle entry and immunoglobulin production (CD70). The PBMCs from AGS subjects also had increased TNF and IFN-gamma mRNA expression compared to controls. AGS is associated with a distinct gene expression profile in circulating PBMCs. DEGs related to antigen presentation, antigen-experienced T-cells, and type 2 immune responses may promote the development of alpha-gal specific IgE and the maintenance of AGS.

Macrophages in food allergy: an enigma

Macrophages, the characteristic cell type in inflammatory reactions, participate in a variety of immunological events in humans and other mammals. They act as regulatory switches for both innate and acquired arms of immune system and play a vital role in tissue repair. Recent studies have shown the possible role of macrophages in food allergic reactions. Since, there is involvement of alveolar as well as peritoneal macrophages in the pathogenesis of several food allergies, the present review covers the relevance of macrophage related immunological response in food allergic reactions.

Anti-acids lead to immunological and morphological changes in the intestine of BALB/c mice similar to human food allergy

We have shown that anti-acid medication for treating dyspeptic disorders can block protein digestion and induce a higher risk for food sensitization. This mechanism was confirmed in human and animal studies on the humoral as well as the cellular level. Here we aimed to investigate the outcome of the treatment with the anti-acid drug sucralfate on the intestine in our murine model, assuming that morphological and immunological changes will occur. BALB/c mice were fed codfish extract plus sucralfate. Antibodies were examined in ELISA, RBL assay and Western blot. Quantitative morphological analysis of the intestine was performed by design-based stereology, focussing on epithelium, lamina propria, smooth muscle, eosinophils and CD3(+) cells. Histological analyses were performed after H&E-, PAS- and Congo red-staining, while immune histochemistry was done for detection of CD3(+) cells. Codfish-specific IgE and its activity in RBL assay confirmed the Th2-response after treatment with sucralfate. The reactivity pattern of murine IgE in Western blot was similar to allergic patients' IgE. Histological examination showed more slender villi in the duodenum, and increased goblet cell mucus in the cecum after sucralfate treatment. Stereological analyses of the intestine revealed higher eosinophil/CD3(+) ratios, decreased mean thickness of the epithelium of duodenum and cecum, and thinner smooth muscle cell layer in the colon of food allergic mice. Anti-acid treatment with sucralfate induces changes in the structure of epithelium and villi, and an increase in eosinophils and mucus-producing cells in the intestine. Therefore, this medication leads to sensitization against food with changes typical for food allergy also in the intestine.

The laboratory diagnosis of food allergies

A dolgozat bemutatja a leggyakoribb hazai allergéneket, az ételallergiák különböző formáit, diagnosztikájuk módjait, különös tekintettel az in vitro laboratóriumi diagnosztika lehetőségeire. A megfogalmazott gondolatok összhangban vannak a European Academy of Allergology and Clinical Immunology és a Klinikai Immunológiai és Allergológiai Szakmai Kollégium ajánlásaival.

Cow's milk allergy: a complex disorder

Cow's milk allergy (CMA) is a complex disorder. Numerous milk proteins have been implicated in allergic responses and most of these have been shown to contain multiple allergenic epitopes. There is considerable heterogeneity amongst allergic individuals for the particular proteins and epitopes to which they react, and to further complicate matters, allergic reactions to cow's milk are driven by more than one immunological mechanism. Finally, the incidence and dominant allergic mechanisms change with age, with IgE-mediated reactions common in infancy and non-IgE-mediated reactions dominating in adults. The complexity of CMA has lead to many public misconceptions about this disorder, including confusion with lactose intolerance and frequent self-misdiagnosis. Indeed, the prevalence of self-diagnosed CMA in the community is 10-fold higher than the clinically proven incidence, suggesting a sizable population is unnecessarily eschewing dairy products. Avoidance of dairy foods, whether for true or perceived CMA, carries with it nutritional consequences and the provision of appropriate nutritional advice is important. In this review, the epidemiology and natural course of CMA is discussed along with our current understanding of its triggers and immunological mechanisms. We examine current strategies for the primary and secondary prevention of allergic sensitization and the ongoing search for effective therapies to ultimately cure CMA.

Bioassay detects soluble MAdCAM-1 in body fluids

Mucosal addressin cell adhesion molecule (MAdCAM-1) is a key player in mediating the infiltration of leucocytes into chronically inflamed tissues. Five anti-MAdCAM-1 monoclonal antibodies (mAb), designated 17F5, 201F7, 314G8, 377D10 and 355G8, were generated by fusion of P3 x 63Ag8.653 myeloma cells with spleen cells from BALB/c mice immunized with recombinant human MAdCAM-1-Fc. The latter four mAb recognize the ligand-binding first Ig domain, and block T -cell adhesion to MAdCAM-1. The non-blocking mAb 17F5 recognizes the mucin domain. Extensive analysis of a large panel of paraffin-embedded human tissues revealed that the 314G8 mAb detected MAdCAM-1 on venules in the spleen and small intestine. MAdCAM-1 was strongly expressed in the synovium of osteoarthritis patients, predominantly on the endothelial lining of blood vessels, but also within the vessel lumen. An ELISA, based on mAb 377D10 and 355G8, was developed to determine whether soluble MAdCAM-1 was present in body fluids, and to measure the levels present. The assay detected soluble MAdCAM-1 in the serum and urine of healthy donors, at levels similar to those of soluble forms of the related CAM, ICAM-1 and VCAM-1. The anti-MAdCAM-1 antibodies and assay developed here may be useful therapeutically in the treatment of inflammation in humans. Similarly, they may be useful diagnostically to monitor the presence and levels of MAdCAM-1.

Chronic allergy to dietary ovalbumin induces lymphocyte migration to rat small intestinal mucosa that is inhibited by MAdCAM-1

Few models have described a chronic food allergy with morphological changes in the intestinal mucosa. Here we established an ovalbumin (OVA)-induced, cell-mediated, allergic rat model and examined lymphocyte migration in the gut. Brown Norway rats were intraperitoneally sensitized to OVA and then given 10 mg OVA/day by gastric intubation for 6 wk. Lymphocyte subsets and adhesion molecules were examined immunohistochemically, and the migration of T lymphocytes to microvessels of Peyer's patches and villus mucosa was observed by using an intravital microscope. Serum OVA-specific IgG and IgE levels were increased in animals repeatedly exposed to OVA. Significant villus atrophy and increased crypt depth was accompanied by increased infiltration of T lymphocytes in the small intestinal mucosa of the group given OVA. Expression of rat mast cell protease II and of mucosal addressin cell adhesion molecule-1 (MAdCAM-1) was also increased in these groups. The administration of anti-MAdCAM-1 antibody significantly attenuated the OVA-induced changes in the mucosal architecture and in CD4 T lymphocyte infiltration. Intravital observation demonstrated that in rats with a chronic allergy, T lymphocytes significantly accumulated in villus microvessels as well as in Peyer's patches via a MAdCAM-1-dependent process. Our model of chronic food allergy revealed that lymphocyte migration was increased with MAdCAM-1 upregulation.

Chemokines in eosinophil-associated gastrointestinal disorders

Eosinophil-associated gastrointestinal disorders (EGDs) are characterized by a pronounced cellular inflammation. Recent clinical and experimental investigations have implicated a family of molecules known as chemokines in the regulation of leukocyte recruitment in these diseases. The underlying cellular and molecular mechanisms involved in chemokine-mediated cellular infiltration are largely unknown. In this review, we describe the role of CD4+ T cells and eosinophils in the clinical manifestations of EGDs and discuss the current understanding of the role of chemokines in the recruitment of these cells in the expression of diseases.

Expression of intercellular adhesion molecules on circulating lymphocytes in relation to different manifestations of cow's milk allergy

BACKGROUND

The complex interactions between immune cells are partly mediated by different adhesion molecules, but little is known about their role in the systemic immunoinflammatory process following sensitization to food antigens in early infancy.

OBJECTIVE

The aim of this study was to investigate the expression of intercellular adhesion molecule-1 (ICAM-1or CD54) and the alpha subunits of its ligands' lymphocyte function-associated antigen-1 (LFA-1) (alphaL subunit or CD11a) and Mac-1 (alphaM subunit or CD11b) on peripheral blood leucocytes in infants with cow's milk allergy (CMA) and in healthy controls.

METHODS

Thirty-nine breastfed infants, aged from 0.6 to 8.3 months, and their lactating mothers were included in the study from delivery onwards. During follow-up, 25 infants developed CMA and 14 remained healthy. Expressions of CD54 and CD11b on peripheral blood leucocytes were evaluated by flow cytometry. In addition, the expression of CD11a on peripheral blood leucocytes was analysed by immunocytochemistry. Mothers' milk samples were collected and their leucocyte content was evaluated using a light microscope.

RESULTS

The frequency of ICAM-1 expressing peripheral blood lymphocytes was significantly higher in patients with CMA than in healthy infants (P=0.03, Mann-Whitney U-test). Furthermore, the high proportion of ICAM-1-expressing cells was associated with gastrointestinal and multiorgan symptoms in the CMA infants. There was no significant difference in the expression of Mac-1 alphaM on lymphocytes in our study groups, but the LFA-1 alphaL expression seemed to be higher in the IgE-mediated CMA.

CONCLUSION

We suggest that the high expression of ICAM-1 on peripheral blood lymphocytes may reflect enhanced stimulation of T cells in vivo and their migration to the effector tissues in an early-phase of developing CMA. Furthermore, high ICAM-1 expression may be associated with the presence of multiorgan manifestations of CMA, whereas high LFA-1 expression may reflect the IgE-mediated disease.

Cytokines and adhesion molecules in duodenal mucosa of children with delayed-type food allergy

OBJECTIVES

The aim was to investigate the expression of cytokines, adhesion molecules, and activation and proliferation markers in duodenal biopsies from children with delayed-type food allergy (FA).

METHODS

Seven children with untreated FA (uFA), seven children with treated FA (tFA) to cow milk and/or cereals, and five normal controls furnished duodenal biopsy specimens. Additionally, five pediatric patients with celiac disease were included, serving exclusively as positive controls for in situ hybridization. Interferon-gamma (IFN-gamma), interleukin-4 (IL-4), adhesion molecules, and activation markers were detected by immunohistochemistry, and expression of IFN-gamma and IL-4 messenger RNA was revealed by in situ hybridization.

RESULTS

uFA patients had a higher density of IFN-gamma positive cells in the lamina propria than did tFA patients and controls (P = 0.053 and P = 0.018). Moreover, the uFA patients exhibited a higher proportion of crypt cells in mitosis than did tFA patients (P = 0.026), and stronger staining of HLA-DR in the crypts and increased density of gammadelta-T cell receptor-positive intraepithelial lymphocytes than did controls (P = 0.048 and P = 0.010). The densities of alpha(4)beta(7) positive cells in the lamina propria tended to be higher in controls than in uFA or tFA patients (P = 0.106, P = 0.073). Expression of IL-4 mRNA was significantly higher in celiac patients than in the other study groups (uFA P = 0.006, tFA P = 0.010; controls P = 0.029), and celiac patients showed higher expression of IFN-gamma mRNA than did tFA patients or controls (P = 0.017 and P = 0.016).

CONCLUSIONS

As expected, Th1 dominance was present in the lamina propria of children with delayed-type FA. It may cause activation of epithelial cells and increase their turnover.