Severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) is an emerging coronavirus that belongs to the β‐genus, causing the outbreak of coronavirus disease 19 (COVID‐19). SARS‐CoV‐2 infection can stimulate a pronounced immune response in the host, which embodies in the decrease of lymphocytes and aberrant increase of cytokines in COVID‐19 patients. SARS‐CoV‐2 RNA and proteins interact with various pattern recognition receptors that switch on antiviral immune responses to regulate viral replication and spreading within the host in vivo. However, overactive and impaired immune responses also cause immune damage and subsequent tissue inflammation. This article focuses on the dual roles of immune system during SARS‐CoV‐2 infection, providing a theoretical basic for identifying therapeutic targets in a situation with an unfavourable immune reaction.

中文翻译：

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SARS-CoV-2 感染诱导的免疫反应：朋友还是敌人？

严重急性呼吸综合征冠状病毒 2 (SARS-CoV-2) 是一种新出现的冠状病毒，属于 β 属，导致冠状病毒病 19 (COVID-19) 的爆发。SARS-CoV-2 感染可刺激宿主产生明显的免疫反应，表现为 COVID-19 患者淋巴细胞减少和细胞因子异常增加。SARS-CoV-2 RNA 和蛋白质与各种模式识别受体相互作用，这些受体开启抗病毒免疫反应，以调节病毒在体内的复制和传播。然而，过度活跃和受损的免疫反应也会导致免疫损伤和随后的组织炎症。本文重点关注免疫系统在 SARS-CoV-2 感染过程中的双重作用，