High Prevalence of Allergic Disorders but No Specific Immune Phenotype Pattern in Children Awaiting Transplantation
1University of Alberta, Edmonton, AB, Canada, 2Hospital for Sick Children, Toronto, ON, Canada, 3McGill University, Montreal, QC, Canada, 4University of British Columbia, Vancouver, BC, Canada, 5University of Calgary, Calgary, AB, Canada, 6University of Manitoba, Winnipeg, MB, Canada, 7Université de Montréal, Montreal, QC, Canada
Meeting: 2019 American Transplant Congress
Abstract number: B67
Keywords: Heart transplant patients, Lymphocytes, Outcome, Pediatric
Session Information
Session Name: Poster Session B: Biomarkers, Immune Monitoring and Outcomes
Session Type: Poster Session
Date: Sunday, June 2, 2019
Session Time: 6:00pm-7:00pm
Presentation Time: 6:00pm-7:00pm
Location: Hall C & D
*Purpose: Allergic disorders (AD) occur more frequently in children after transplantation (Tx) compared to healthy children, reflecting an imbalance of the immune system in the context of immunosuppression (including immune cell-depleting induction) that may also be favoured by heritable factors present before Tx. We previously found a lack of naïve regulatory T cells (Tregs) and other alterations of lymphocyte phenotypes associated with AD in children after heart Tx. We assessed whether these patterns are present pre-Tx by comparing immune profiles of children awaiting Tx with and without AD.
*Methods: This multicenter collaboration was conducted within the POSITIVE study, part of the Canadian National Transplant Research Program. Clinical data were collected into a REDCap database. Lymphocytes were isolated from pre-Tx blood via density gradient centrifugation and subtyped by flow cytometry with a focus on regulatory cells. Cell distributions were compared between patients with and without AD across kidney, heart and liver Tx groups (KTx, HTx, LTx) and in correlation to age.
*Results: Of the 114 patients, 33% experienced one or more AD pre-Tx, with prevalence of 40% in KTx-, 34% in HTx- and 21% in LTx-listed children. Of patients with one or more AD, 24% experienced asthma, 47% rhinitis and 47% eczema pre-Tx. Tregs, regulatory B cells, memory T cells and memory B cells were not significantly different between AD and non-AD groups. Within the HTx group, CD45RA+ naive Tregs were in trend less frequent in patients with AD than patients without AD (p = 0.079).
*Conclusions: AD are more common in children awaiting HTx, KTx, and LTx compared to the general population, with the lowest prevalence in LTx-listed children. The AD-associated immune phenotype alterations previously described were not present in these children, except in trend in HTx-listed children. This indicates that the AD-associated imbalance evolves or manifests with transplant and immune suppression.
To cite this abstract in AMA style:
Kim TB, Avitzur Y, Ionescu L, Allen U, Mital S, Foster B, Blydt-Hansen T, Hamiwka L, Birk P, Phan V, Urschel S. High Prevalence of Allergic Disorders but No Specific Immune Phenotype Pattern in Children Awaiting Transplantation [abstract]. Am J Transplant. 2019; 19 (suppl 3). https://atcmeetingabstracts.com/abstract/high-prevalence-of-allergic-disorders-but-no-specific-immune-phenotype-pattern-in-children-awaiting-transplantation/. Accessed December 10, 2024.« Back to 2019 American Transplant Congress