Preparation of viral stocks for clinical isolates of the SARS-CoV-2 Omicron variants. Severe acute respiratory syndrome coronavirus 2

To compare the virological properties of the SARS-CoV-2 variants, Omicron BA.1, BA.2, and BA.5, we performed experiments using clinical isolates of BA.1 (EPI_ISL_7418017), BA.2 (EPI_ISL_9595859), BA.5 (EPI_ISL_12812500), and the ancestral variant B.1.1 (EPI_ISL_479681). To verify the genome sequence of the working virus, we performed viral RNA-sequencing of the viral stock before the experiments.