Per SARS CoV, various cleaved and uncleaved varieties of the SARS-CoV-2 spike protein. Notably, the cleavage pattern towards the the SARS spike positive Command from Calu3 cells, a respiratory cell line, may differ somewhat and will signal differences involving proteolytic cleavage on the spike proteins among the two viruses on https://www.pinterest.com/pin/993958580252569164/