Forming the outer body barrier, our skin is permanently exposed to pathogens and environmental hazards. Therefore, skin diseases are among the most common disorders. In many of them, the immune system plays a crucial pathogenetic role. For didactic and therapeutic reasons, classification of such immune-mediated skin diseases according to the underlying dominant immune mechanism rather than to their clinical manifestation appears to be reasonable. Immune-mediated skin diseases may be mediated mainly by T cells, by the humoral immune system, or by uncontrolled unspecific inflammation. According to the involved T cell subpopulation, T cell–mediated diseases may be further subdivided into T1 cell–dominated (e.g., vitiligo), T2 cell–dominated (e.g., acute atopic dermatitis), T17/T22 cell–dominated (e.g., psoriasis), and Treg cell–dominated (e.g., melanoma) responses. Moreover, T cell–dependent and -independent responses may occur simultaneously in selected diseases (e.g., hidradenitis suppurativa). The effector mechanisms of the respective T cell subpopulations determine the molecular changes in the local tissue cells, leading to specific microscopic and macroscopic skin alterations. In this article, we show how the increasing knowledge of the T cell biology has been comprehensively translated into the pathogenetic understanding of respective model skin diseases and, based thereon, has revolutionized their daily clinical management.

中文翻译：

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皮肤炎症中的 T 细胞病理学。


我们的皮肤形成外部身体屏障，永久暴露于病原体和环境危害中。因此，皮肤病是最常见的疾病之一。在其中许多疾病中，免疫系统起着至关重要的致病作用。出于教学和治疗的原因，根据潜在的主导免疫机制而不是其临床表现对此类免疫介导的皮肤病进行分类似乎是合理的。免疫介导的皮肤病可能主要由 T 细胞、体液免疫系统或不受控制的非特异性炎症介导。根据所涉及的T细胞亚群，T细胞介导的疾病可进一步细分为T1细胞主导的（例如白癜风）、T2细胞主导的（例如急性特应性皮炎）、T17/T22细胞主导的（例如银屑病） ）和 Treg 细胞主导的反应（例如黑色素瘤）。此外，在某些疾病（例如化脓性汗腺炎）中，T 细胞依赖性和非依赖性反应可能同时发生。各个T细胞亚群的效应机制决定了局部组织细胞的分子变化，导致特定的微观和宏观皮肤变化。在本文中，我们展示了如何将日益增长的 T 细胞生物学知识全面转化为对各种模型皮肤病的发病机制的理解，并在此基础上彻底改变了日常临床管理。