Acute FPIES reactions are associated with an IL-17 inflammatory signature
Journal of Allergy and Clinical Immunology, 2021
Berin M., Lozano-Ojalvo D., Agashe C., Baker M., Bird J., Nowak-Wegrzyn A.
| Disease area | Application area | Sample type | Products |
|---|---|---|---|
Immunological & Inflammatory Diseases | Pathophysiology |
Abstract
Background
Food protein–induced enterocolitis syndrome (FPIES) is a non–IgE-mediated food allergy characterized by profuse vomiting within hours of ingestion of the causative food. We have previously reported that FPIES is associated with systemic innate immune activation in the absence of a detectable antigen-specific antibody or T-cell response. The mechanism of specific food recognition by the immune system remains unclear.
Objective
Our aim was to identify immune mechanisms underlying FPIES reactions by proteomic and flow cytometric analysis of peripheral blood.
Methods
Children with a history of FPIES underwent supervised oral food challenge. Blood samples were taken at baseline, at symptom onset, and 4 hours after symptom onset. We analyzed samples from 23 children (11 reactors and 12 outgrown). A total of 184 protein markers were analyzed by proximity ligation assay and verified by multiplex immunoassay. Analysis of cell subset activation was performed by mass cytometry and spectral cytometry.
Results
Symptomatic FPIES challenge results were associated with significant elevation of levels of cytokines and chemokines, including IL-17 family markers (IL-17A, IL-22, IL-17C, and CCL20) and T-cell activation (IL-2), and innate inflammatory markers (IL-8, oncostatin M, leukemia inhibitory factor, TNF-α, IL-10, and IL-6). The level of the mucosal damage marker regenerating family member 1 alpha (REG1A) was also significantly increased. These biomarkers were not increased in asymptomatic challenges or IgE-mediated allergy. The level of phospho-STAT3 was significantly elevated in myeloid and T cells after challenge in individuals with symptoms. Mass cytometry indicated preferential activation of nonconventional T-cell populations, including γδ T cells and CD3+CD4–CD8–CD161+ cells; however, the potential sources of IL-17 in PBMCs were primarily CD4+ TH17 cells.
Conclusions
These results demonstrate a unique IL-17 signature and activation of innate lymphocytes in FPIES.