Mast cells have existed long before the development of adaptive immunity, although they have been given different names. Thus, in the marine urochordate Styela plicata, they have been designated as test cells. However, based on their morphological characteristics (including prominent cytoplasmic granules) and mediator content (including heparin, histamine, and neutral proteases), test cells are thought to represent members of the lineage known in vertebrates as mast cells. So this lineage presumably had important functions that preceded the development of antibodies, including IgE. Yet mast cells are best known, in humans, as key sources of mediators responsible for acute allergic reactions, notably including anaphylaxis, a severe and potentially fatal IgE-dependent immediate hypersensitivity reaction to apparently harmless antigens, including many found in foods and medicines. In this review, we briefly describe the origins of tissue mast cells and outline evidence that these cells can have beneficial as well as detrimental functions, both innately and as participants in adaptive immune responses. We also discuss aspects of mast cell heterogeneity and comment on how the plasticity of this lineage may provide insight into its roles in health and disease. Finally, we consider some currently open questions that are yet unresolved.

中文翻译：

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炎症和疾病中的肥大细胞：最新进展和持续关注。

肥大细胞早在适应性免疫发展之前就已经存在，尽管它们被赋予了不同的名称。因此，在海洋尿脊索动物 Styela plicata 中，它们被指定为测试细胞。然而，基于它们的形态特征（包括突出的细胞质颗粒）和介质含量（包括肝素、组胺和中性蛋白酶），测试细胞被认为代表了脊椎动物中称为肥大细胞的谱系成员。因此，该谱系可能具有先于抗体（包括 IgE）开发的重要功能。然而，肥大细胞在人类中最为人所知，它是导致急性过敏反应的介质的主要来源，特别是包括过敏反应，一种严重且可能致命的 IgE 依赖性即时超敏反应，对明显无害的抗原，包括许多存在于食品和药物中。在这篇综述中，我们简要描述了组织肥大细胞的起源，并概述了这些细胞可以具有有益和有害功能的证据，无论是先天的还是作为适应性免疫反应的参与者。我们还讨论了肥大细胞异质性的各个方面，并评论了该谱系的可塑性如何可以深入了解其在健康和疾病中的作用。最后，我们考虑一些目前尚未解决的悬而未决的问题。我们还讨论了肥大细胞异质性的各个方面，并评论了该谱系的可塑性如何可以深入了解其在健康和疾病中的作用。最后，我们考虑一些目前尚未解决的悬而未决的问题。我们还讨论了肥大细胞异质性的各个方面，并评论了该谱系的可塑性如何可以深入了解其在健康和疾病中的作用。最后，我们考虑一些目前尚未解决的悬而未决的问题。