Division of Allergic Diseases, Department of Internal Medicine, Mayo Clinic, Rochester, MN 55905, USA.
Immunol Rev. 2011 Jul;242(1):161-77. doi: 10.1111/j.1600-065X.2011.01026.x.
Eosinophils are leukocytes resident in mucosal tissues. During T-helper 2 (Th2)-type inflammation, eosinophils are recruited from bone marrow and blood to the sites of immune response. While eosinophils have been considered end-stage cells involved in host protection against parasite infection and immunopathology in hypersensitivity disease, recent studies changed this perspective. Eosinophils are now considered multifunctional leukocytes involved in tissue homeostasis, modulation of adaptive immune responses, and innate immunity to certain microbes. Eosinophils are capable of producing immunoregulatory cytokines and are actively involved in regulation of Th2-type immune responses. However, such new information does not preclude earlier observations showing that eosinophils, in particular human eosinophils, are also effector cells with proinflammatory and destructive capabilities. Eosinophils with activation phenotypes are observed in biological specimens from patients with disease, and deposition of eosinophil products is readily seen in the affected tissues from these patients. Therefore, it would be reasonable to consider the eosinophil a multifaceted leukocyte that contributes to various physiological and pathological processes depending on their location and activation status. This review summarizes the emerging concept of the multifaceted immunobiology of eosinophils and discusses the roles of eosinophils in health and disease and the challenges and perspectives in the field.
嗜酸性粒细胞是驻留在黏膜组织中的白细胞。在辅助性 T 细胞 2（Th2）型炎症期间，嗜酸性粒细胞从骨髓和血液中募集到免疫反应部位。虽然嗜酸性粒细胞被认为是参与宿主对寄生虫感染和过敏疾病中免疫病理学的保护性的终末细胞，但最近的研究改变了这一观点。嗜酸性粒细胞现在被认为是多功能白细胞，参与组织稳态、调节适应性免疫反应和对某些微生物的固有免疫。嗜酸性粒细胞能够产生免疫调节细胞因子，并积极参与调节 Th2 型免疫反应。然而，这种新信息并没有排除更早的观察结果，即嗜酸性粒细胞，特别是人类嗜酸性粒细胞，也是具有促炎和破坏性能力的效应细胞。在疾病患者的生物标本中观察到具有激活表型的嗜酸性粒细胞，并且在这些患者的受影响组织中容易看到嗜酸性粒细胞产物的沉积。因此，考虑到嗜酸性粒细胞是一种根据其位置和激活状态而有助于各种生理和病理过程的多面白细胞，这是合理的。本综述总结了嗜酸性粒细胞的多方面免疫生物学的新出现概念，并讨论了嗜酸性粒细胞在健康和疾病中的作用以及该领域的挑战和展望。
