During the past years, there has been a global outbreak of allergic diseases, presenting a considerable medical and socioeconomical burden. A large fraction of allergic diseases is characterized by a type 2 immune response involving Th2 cells, type 2 innate lymphoid cells, eosinophils, mast cells, and M2 macrophages. Biomarkers are valuable parameters for precision medicine as they provide information on the disease endotypes, clusters, precision diagnoses, identification of therapeutic targets, and monitoring of treatment efficacies. The availability of powerful omics technologies, together with integrated data analysis and network-based approaches can help the identification of clinically useful biomarkers. These biomarkers need to be accurately quantified using robust and reproducible methods, such as reliable and point-of-care systems. Ideally, samples should be collected using quick, cost-efficient and noninvasive methods. In recent years, a plethora of research has been directed toward finding novel biomarkers of allergic diseases. Promising biomarkers of type 2 allergic diseases include sputum eosinophils, serum periostin and exhaled nitric oxide. Several other biomarkers, such as pro-inflammatory mediators, miRNAs, eicosanoid molecules, epithelial barrier integrity, and microbiota changes are useful for diagnosis and monitoring of allergic diseases and can be quantified in serum, body fluids and exhaled air. Herein, we review recent studies on biomarkers for the diagnosis and treatment of asthma, chronic urticaria, atopic dermatitis, allergic rhinitis, chronic rhinosinusitis, food allergies, anaphylaxis, drug hypersensitivity and allergen immunotherapy. In addition, we discuss COVID-19 and allergic diseases within the perspective of biomarkers and recommendations on the management of allergic and asthmatic patients during the COVID-19 pandemic.

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过敏性疾病生物标志物研究进展与亮点

在过去的几年里，过敏性疾病在全球范围内爆发，带来了巨大的医疗和社会经济负担。大部分过敏性疾病的特征在于涉及 Th2 细胞、2 型先天淋巴细胞、嗜酸性粒细胞、肥大细胞和 M2 巨噬细胞的 2 型免疫反应。生物标志物是精准医学的重要参数，因为它们提供了有关疾病内型、集群、精准诊断、治疗靶点识别和治疗效果监测的信息。强大的组学技术的可用性，以及集成的数据分析和基于网络的方法可以帮助识别临床有用的生物标志物。这些生物标志物需要使用可靠且可重复的方法（例如可靠的即时护理系统）进行准确量化。理想情况下，应使用快速、经济高效和无创的方法收集样本。近年来，大量研究致力于寻找过敏性疾病的新生物标志物。2 型过敏性疾病的有希望的生物标志物包括痰嗜酸性粒细胞、血清骨膜素和呼出气一氧化氮。其他几种生物标志物，如促炎介质、miRNA、类花生酸分子、上皮屏障完整性和微生物群变化可用于过敏性疾病的诊断和监测，并且可以在血清、体液和呼出的空气中进行量化。在此，我们回顾了最近关于诊断和治疗哮喘、慢性荨麻疹、特应性皮炎、过敏性鼻炎、慢性鼻窦炎、食物过敏、过敏反应、药物超敏反应和过敏原免疫治疗的生物标志物的研究。此外，