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: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).
Project description:This study profiled the epigenomes and transcriptomes of total nCD4T cell populations from adolescents with peanut-only (single food allergy- SA) and multi-food allergy (MA) at quiescence and following activation with anti-CD3/antiCD28
Project description:This study profiled the epigenomes and transcriptomes of total nCD4T cell populations from adolescents with peanut-only (single food allergy- SA) and multi-food allergy (MA) at quiescence and following activation with anti-CD3/antiCD28
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: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). We found distinct epigenetic and transcriptomic differences between food allergic patients and controls, in addition to SA- and MA- group specific signatures, with
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:MS/MS analysis of the peanut protein extract (PPE) confirmed the presence of the four major peanut allergens and identified the presence of Ara h 1 isotypes, Ara h 2 isotypes, Ara h 3 isotypes, Ara h 6 isotypes and Ara h 7 isotypes. Allergen-specific immunotherapy (IT) is emerging as a viable option for treatment of peanut allergy. Yet, prophylactic IT remains unexplored despite early introduction of peanut in infancy was shown to prevent allergy. There is a need to understand how allergens interact with the immune system depending on the route of administration, and how different dosages of allergen may protect from sensitisation and a clinical active allergy. Here we compared peanut allergen delivery via the oral, sublingual (SL), intragastric (IG) and subcutaneous (SC) routes for the prevention of peanut allergy in Brown Norway (BN) rats. BN rats were administered PBS or three different doses of PPE via either oral IT (OIT), SLIT, IGIT and SCIT followed by intraperitoneal (IP) injections of PPE to assess the protection from peanut sensitisation. The development of IgE and IgG1 responses to PPE and the major peanut allergens were evaluated by ELISAs. The clinical response to PPE was assessed by an ear swelling test (EST) and proliferation was assessed by stimulating splenocytes with PPE. Low and medium dose OIT (1 and 10 mg) and all doses of SCIT (1, 10, 100 µg) induced sensitisation to PPE, whereas high dose OIT (100 mg), SLIT (10, 100 or 1000 µg) or IGIT (1, 10 and 100 mg) did not. High dose OIT and SLIT as well as high and medium dose IGIT prevented sensitisation from the following IP injections of PPE and suppressed PPE-specific IgE levels in a dose-dependent manner. Hence, administration of peanut protein via different routes confers different risks for sensitisation and protection from peanut allergy development. Overall, the IgE levels toward the individual major peanut allergens followed the PPE-specific IgE levels. Collectively, this study showed that the preventive effect of allergen-specific IT is determined by the interplay between the specific site of PPE delivery for presentation to the immune system, and the allergen quantity, and that targeting and modulating tolerance mechanisms at specific mucosal sites may be a prophylactic strategy for prevention of peanut allergy.
Project description:Food allergy affects an estimated 8% of children in the US, with increasing severity and global prevalence. Using single-cell RNA sequencing and paired TCR sequencing, we assessed the transcriptomes of CD154+ and CD137+ peanut-reactive T helper cells from 12 peanut-allergic patients longitudinally throughout peanut oral immunotherapy. These results demonstrate a differential response to OIT among subsets of peanut-reactive T helper cells, and indicate that non-Th2 activation signatures may be associated with clinical outcomes.