Coronavirus disease 2019 (COVID-19) is an infectious disease caused by SARS-CoV-2, a newly discovered coronavirus that exhibits many similarities with the severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS) coronaviruses (SARS-CoV and MERS-CoV, respectively). The definite pathogenesis and immunological influences of SARS-CoV-2 have not been fully elucidated. Therefore, we constructed a brief summary comparison of SARS-CoV-2, SARS-CoV, and MERS-CoV infections regarding their immunological changes. In addition, we further investigated the immunological differences between severe and nonsevere COVID-19 cases, and we searched for possible immunological predictors of the patient outcome by reviewing case series studies to date. Possible immunological predictors of a poor outcome are leukocytosis, neutrophilia, lymphopenia (both CD4 and CD8 T cells), an increased neutrophil-to-lymphocyte ratio (NLR), and increased levels of pro-inflammatory cytokines (IL-6 and TNF-α), Th1 cytokines (IL-2 and IFN-γ), regulatory T cell cytokines (IL-10) and Th17 cytokines (IL-17). A more precise immunological map needs to be established, which may assist in diagnosing this disease and facilitate immunological precision medicine treatment.

冠状病毒病 2019 (COVID-19) 是由 SARS-CoV-2 引起的传染病，SARS-CoV-2 是一种新发现的冠状病毒，与严重急性呼吸综合征 (SARS) 和中东呼吸综合征 (MERS) 冠状病毒 (SARS-CoV) 有许多相似之处和中东呼吸综合征冠状病毒）。SARS-CoV-2 的确切发病机制和免疫学影响尚未完全阐明。因此，我们对 SARS-CoV-2、SARS-CoV 和 MERS-CoV 感染的免疫学变化进行了简要总结比较。此外，我们进一步调查了重症和非重症 COVID-19 病例之间的免疫学差异，并通过回顾迄今为止的病例系列研究来寻找患者预后的可能免疫学预测因子。不良结果的可能免疫学预测因子是白细胞增多、中性粒细胞增多、淋巴细胞减少（CD4 和 CD8 T 细胞）、中性粒细胞与淋巴细胞比率 (NLR) 增加以及促炎细胞因子（IL-6 和 TNF-α）、Th1 细胞因子（IL-2 和 IFN-γ）水平升高)、调节性 T 细胞因子 (IL-10) 和 Th17 细胞因子 (IL-17)。需要建立更精确的免疫学图谱，这可能有助于诊断该疾病并促进免疫学精准医学治疗。