Fig 6. AXL knockout reduces viral loads and ablates inhibition by bemcentinib.

A) Flow cytometry histograms depicting AXL surface staining (black) and secondary only background (gray) on parental, Cas9 expressing H1650 cells or Cas9/guide RNA treated and cloned cells, demonstrating loss of AXL expression. H1650 AXL knockout cells were generated by lentiviral transduction of Cas9 and gRNA targeting AXL, followed by selection, enrichment, and biological cloning. B) H1650 AXL^neg and H1650 Cas9 (parental) lines were challenged with SARS-CoV-2 at indicated MOIs. At 24hpi, viral loads were assessed by RT-qPCR. C) H1650 parental and AXL^neg lines were treated with the indicated concentration of bemcentinib and challenged with SARS-CoV-2 (MOI = 0.5) and viral loads determine by RT-qPCR 24 hpi. Data are pooled from 3 independent experiments (B, C) or are representative of at least 3 experiments (A). Data represented as means ± SEM. Multiple t-tests; asterisks represent p < 0.05 (B). Student’s t-tests comparing Mock and 1μM; p values shown (C).