Project description:Peanut allergy reaction severity correlates with increased intestinal epithelial cell (IEC) barrier permeability. CC027/GeniUnc mice develop peanut allergy by intragastric administration of peanut proteins without adjuvant. We report that peanut-allergic CC027/GeniUnc mice showed increased IEC barrier permeability and systemic peanut allergen Ara h 2 after challenge. Jejunal epithelial cell transcriptomics showed effects of peanut allergy on IEC proliferation, survival, and metabolism, and revealed IEC-predominant angiopoietin like-4 (Angptl4) as a unique feature of CC027/GeniUnc peanut allergy. Peanut-allergic pediatric patients demonstrated significantly higher serum ANGPTL4 compared to non-peanut-allergic but atopic patients, highlighting its potential as a biomarker of peanut allergy.
Project description:Peanut protein is a remarkably potent food allergen in susceptible individuals. The frequency of peanut allergy is approximately 1% in the US population. Peanut allergy often presents with severe symptoms, and it is seldom outgrown. We sought to understand how peanut protein activates human dendritic cells, which are crucial in promoting the activation and differentiation of pathogenic peanut-specific Th2 cells that drive allergic responses.
Project description:Peanut allergy is increasingly prevalent among children in the United States and other industrialized countries and is now estimated to affect approximately 2% of children. While there are currently no approved treatment options, peanut allergy usually persists into adulthood, can be life-threatening, and accounts for most deaths related to food allergy. Here, we track peanut-reactive CD4+ T effector (pTeff) cells using the CD154 up-regulation assay. We found that CRTH2+ pTeff cells and CCR6+ pTeff cells represent two mutually exclusive, non-overlapping cellular and molecular entities involved in food allergic diseases.
Project description:Bone marrow plasma cells (BMPCs) produce durable, infection-resistant IgM, IgG, and IgA antibodies, but in some cases, pro-allergic IgE. Despite this, BMPC sources are unclear. We charted single BMPC transcriptional and clonal heterogeneity in peanut-allergic and non-allergic humans across CD19 protein expression—due to CD19’s inverse correlation to BMPC longevity. Transcriptional and clonal diversity revealed distinct functional modules. Additionally, distributions of somatic hypermutation and intraclonal antibody sequence variance suggest CD19low and CD19high BMPCs arise from recalled memory and germinal center B cells, respectively. Most IgE BMPCs were from peanut-allergic individuals; some bound peanut and potently prevented peanut-driven anaphylaxis in a mouse model. These findings shed light on BMPC origins and identify the bone marrow as a likely source for long-lived pathogenic IgE in peanut allergy.
Project description:This study profiled the epigenomes and transcriptomes of total B cell populations from adolescents with peanut-only (single food allergy- SA) and multi-food allergy (MA).
