{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,8]],"date-time":"2026-07-08T05:17:18Z","timestamp":1783487838867,"version":"3.55.0"},"reference-count":49,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,7,8]],"date-time":"2026-07-08T00:00:00Z","timestamp":1783468800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Immunol."],"abstract":"<jats:p>Eosinophils have traditionally been viewed as terminal effector cells in allergic rhinitis (AR), driving tissue damage through the release of cytotoxic granule proteins and pro-inflammatory mediators. However, accumulating evidence over the past two decades has challenged this paradigm, revealing that eosinophils harbor a substantial immunoregulatory repertoire. This Mini Review synthesizes emerging findings on four underappreciated dimensions of eosinophil immunoregulatory function in the context of AR: (i) the capacity of eosinophils to produce interleukin-10 (IL-10) and engage in functional crosstalk with Foxp3+ regulatory T cells (Tregs); (ii) the dual role of eosinophil-derived transforming growth factor-beta (TGF-\u03b2) in both tissue remodeling and mucosal tolerance; (iii) eosinophil lipid mediator class-switching from pro-inflammatory cysteinyl leukotrienes (CysLTs) to specialized pro-resolving mediators (SPMs); and (iv) the functional heterogeneity between tissue-resident and inflammatory eosinophil subsets. We further discuss the clinical implications of these findings, including the paradoxical outcomes of anti-IL-5 therapies in AR and the potential of immunoregulatory eosinophil markers as biomarkers for allergen-specific immunotherapy (AIT). A deeper understanding of the context-dependent immunoregulatory functions of eosinophils in the nasal mucosa may inform precision therapeutic strategies that selectively target pro-inflammatory eosinophil subsets while preserving their homeostatic and tolerogenic roles.<\/jats:p>","DOI":"10.3389\/fimmu.2026.1888525","type":"journal-article","created":{"date-parts":[[2026,7,8]],"date-time":"2026-07-08T04:50:06Z","timestamp":1783486206000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Eosinophils as immunoregulatory players in allergic rhinitis: beyond cytotoxicity"],"prefix":"10.3389","volume":"17","author":[{"given":"Xinyu","family":"Han","sequence":"first","affiliation":[{"name":"The First Affiliated Hospital of Guangzhou University of Chinese Medicine","place":["Guangzhou, Guangdong, China"]},{"name":"ShenShan Hospital, The First Affiliated Hospital of Guangzhou University of Chinese 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