Project description:Cutaneous exposure to food antigen through impaired skin barrier has been shown to induce epicutaneous sensitization, and thereby cause IgE-mediated food allergy. We examined whether skin barrier impairment deteriorated food allergy symptoms in epicutaneously sensitized mice. To clarify the association between skin inflammation and food allergy symptoms, we analyzed gene expression at skin lesions using a GeneChip.
Project description:Genome wide DNA methylation profiling study of PBMC from 71 unique primary patient blood samples. The Illumina Human Methylation 450k array was used. 29 challenge proven food allergy, 29 sensitized but oral tolerant, 13 non food allergics Mixture of food allergy phenotypes (egg allergic (15), peanut allergic (14)), food sensitization phenotypes (egg sensitized (14), peanut sensitized (15)). 4 samples had technical replicate hybridzations. Bisulphite converted DNA from the 75 samples were hybridised to the Illumina Infinium 450k Human Methylation Beadchip v1.2. Technical replicates were combined during processing, resulting in normalized Beta values for 71 unique primary patient blood samples.
Project description:This study investigated the impact of a high cellulose diet (HCD) on intestinal homeostasis and food allergy development in BALB/c mice. While soluble fibers are known to mitigate FA via short-chain fatty acid (SCFA) production, the role of insoluble fibers like cellulose remains unclear. Mice fed HCD exhibited gut dysbiosis, characterized by increased Proteobacteria, decreased tight junction protein expression, and intestinal barrier impairment, despite unchanged SCFA levels. RNA sequencing revealed HCD-induced upregulation of immune pathways, including the positive regulation of B and T cells differentiation and antigen receptor-mediated signaling pathway. Following ovalbumin (OVA) sensitization, HCD-fed mice displayed exacerbated allergic symptoms, including elevated OVA-specific IgE, IgG, histamine, and mMCP-1 levels. Gut microbiota analysis highlighted enrichment of potentially pathogenic taxa in HCD+OVA groups. Fecal microbiota transplantation (FMT) from HCD donors to antibiotic-treated recipients showed severe food allergy responses, confirming microbiota-mediated effects. These findings demonstrate that HCD exacerbates food allergy through gut microbial dysbiosis, intestinal barrier disruption, and intestinal immune disorder.
Project description:It has been reported that T follicular regulatory (TFR) cells promote IgE in a food allergy model but suppress IgE in a house dust mite (HDM)-induced airway inflammation model. To understand the differential roles of TFR cells in different models, mice were sensitized with peanut plus cholera toxin (PCT) (i.g.) or challenged with HDM (i.n.). TFR cells were sorted from these mice, total RNA was extracted and used for RNA-seq. Naive mice were used as additional control.
Project description:Experimental IgE-mediated food allergy depends on intestinal anaphylaxis driven by interleukin (IL)-9. However, the primary cellular source of IL-9 and the mechanisms underlying the susceptibility to food-induced intestinal anaphylaxis remain unclear. Herein, we have reported the identification of multifunctional IL-9-producing mucosal mast cells (MMC9s) that can secrete prodigious amounts of IL-9 and IL-13 in response to IL-33, and mast cell protease-1 (MCPt-1) in response to antigen and IgE complex crosslinking, respectively. Repeated intragastric antigen challenge induced MMC9 development that required T cells, IL-4, and STAT6 transcription factor, but not IL-9 signals. Mice ablated of MMC9 induction failed to develop intestinal mastocytosis, which resulted in decreased food allergy symptoms that could be restored by adoptively transferred MMC9s. Finally, atopic patients that developed food allergy displayed increased intestinal expression of Il9 and MC-specific transcripts. Thus, the induction of MMC9s is a pivotal step to acquire the susceptibility to IgE-mediated food allergy. dUTP mRNA-Seq profiles of indicated hematopoietic cell lineages were generated on Illumina HiSeq2500. Hematopoietic cells were isolated from Balb/C mice that developed food allergy and bone marrow-derived mast cells were generated from naïve Balb/C mice
Project description:Experimental IgE-mediated food allergy depends on intestinal anaphylaxis driven by interleukin (IL)-9. However, the primary cellular source of IL-9 and the mechanisms underlying the susceptibility to food-induced intestinal anaphylaxis remain unclear. Herein, we have reported the identification of multifunctional IL-9-producing mucosal mast cells (MMC9s) that can secrete prodigious amounts of IL-9 and IL-13 in response to IL-33, and mast cell protease-1 (MCPt-1) in response to antigen and IgE complex crosslinking, respectively. Repeated intragastric antigen challenge induced MMC9 development that required T cells, IL-4, and STAT6 transcription factor, but not IL-9 signals. Mice ablated of MMC9 induction failed to develop intestinal mastocytosis, which resulted in decreased food allergy symptoms that could be restored by adoptively transferred MMC9s. Finally, atopic patients that developed food allergy displayed increased intestinal expression of Il9 and MC-specific transcripts. Thus, the induction of MMC9s is a pivotal step to acquire the susceptibility to IgE-mediated food allergy.