Department of Medicine, University of Massachusetts Chan Medical School, Worcester, MA 01655, USA.
Diabetes Center of Excellence and Program in Molecular Medicine, University of Massachusetts Chan Medical School, Worcester, MA 01655, USA.
Viruses. 2022 Jun 23;14(7):1369. doi: 10.3390/v14071369.
New variants of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) continue to emerge, causing surges, breakthrough infections, and devastating losses-underscoring the importance of identifying SARS-CoV-2 antivirals. A simple, accessible human cell culture model permissive to SARS-CoV-2 variants is critical for identifying and assessing antivirals in a high-throughput manner. Although human alveolar A549 cells are a valuable model for studying respiratory virus infections, they lack two essential host factors for SARS-CoV-2 infection: angiotensin-converting enzyme 2 (ACE2) and transmembrane serine protease 2 (TMPRSS2). SARS-CoV-2 uses the ACE2 receptor for viral entry and TMPRSS2 to prime the SARS-CoV-2 spike protein, both of which are negligibly expressed in A549 cells. Here, we report the generation of a suitable human cell line for SARS-CoV-2 studies by transducing human and into A549 cells. We show that subclones highly expressing ACE2 and TMPRSS2 ("ACE2plus" and the subclone "ACE2plusC3") are susceptible to infection with SARS-CoV-2, including the delta and omicron variants. These subclones express more ACE2 and TMPRSS2 transcripts than existing commercial A549 cells engineered to express ACE2 and TMPRSS2. Additionally, the antiviral drugs EIDD-1931, remdesivir, nirmatrelvir, and nelfinavir strongly inhibit SARS-CoV-2 variants in our infection model. Our data show that ACE2plusC3 cells are highly permissive to SARS-CoV-2 infection and can be used to identify anti-SARS-CoV-2 drugs.
新型严重急性呼吸综合征冠状病毒 2（SARS-CoV-2）不断出现新变体，导致疫情激增、突破性感染和毁灭性损失——这凸显了确定 SARS-CoV-2 抗病毒药物的重要性。一种简单、易于获取且对 SARS-CoV-2 变体具有易感性的人类细胞培养模型，对于以高通量方式识别和评估抗病毒药物至关重要。尽管人肺泡 A549 细胞是研究呼吸道病毒感染的有价值模型，但它们缺乏 SARS-CoV-2 感染的两个重要宿主因子：血管紧张素转换酶 2（ACE2）和跨膜丝氨酸蛋白酶 2（TMPRSS2）。SARS-CoV-2 利用 ACE2 受体进入病毒，利用 TMPRSS2 对 SARS-CoV-2 刺突蛋白进行前体处理，而这两种蛋白在 A549 细胞中表达水平极低。在此，我们通过转导人类 和 到 A549 细胞中，报告了一种适合 SARS-CoV-2 研究的人类细胞系的产生。我们表明，高表达 ACE2 和 TMPRSS2 的亚克隆（“ACE2plus”和亚克隆“ACE2plusC3”）易感染 SARS-CoV-2，包括德尔塔和奥密克戎变体。这些亚克隆表达的 ACE2 和 TMPRSS2 转录本多于现有商业 A549 细胞中表达的 ACE2 和 TMPRSS2。此外，抗病毒药物 EIDD-1931、瑞德西韦、奈玛特韦和奈非那韦在我们的感染模型中强烈抑制 SARS-CoV-2 变体。我们的数据表明，ACE2plusC3 细胞对 SARS-CoV-2 感染高度易感性，可用于鉴定抗 SARS-CoV-2 药物。
