Cell Culture Protocols for SARS-CoV-2 Research

Vero E6 cells (Cercopithecus aethiops-derived epithelial kidney cells, ATCC) were grown in Dulbecco’s modified Eagle’s medium (DMEM; Gibco, catalog no. 41965039) supplemented with 2.5% heat-inactivated fetal calf serum (FCS; Gibco, catalog no. 10270106), 100 units/ml penicillin, 100 μg/ml streptomycin (Thermo Fisher, catalog no. 15140122), 2 mM l-glutamine, 1 mM sodium pyruvate (Pan Biotech, catalog no. P04-8010), and 1× nonessential amino acids (Sigma, catalog no. M7145). Caco-2 cells (human epithelial colorectal adenocarcinoma cells, kindly provided by H. Barth, Ulm University) were grown in the same media but with supplementation of 10% FCS. Calu-3 cells (human epithelial lung adenocarcinoma cells, kindly provided by M. Frick, Ulm University) were cultured in minimum essential Eagle medium (MEM; Sigma, catalog no. M4655) supplemented with 10% FCS (during viral infection) or 20% FCS (at all other times), 100 units/ml penicillin, 100 μg/ml streptomycin, 1 mM sodium pyruvate, and 1× nonessential amino acids. NHLF cells (primary human lung fibroblasts; Lonza), HEK293T ZAP KO cells (10 (link)), and A549 cells (adenocarcinoma human alveolar basal epithelial cells; ATCC) were cultured in DMEM supplemented with 10% FCS, 2 mM μg/ml l-glutamine, 100 units/ml penicillin, and 100 μg/ml streptomycin.