Figure EV1. SARS‐Cov‐2 Spike subunit S1 protein causes a significant increase in the expression of a panel of cytokines in myeloid cells.

• A
  Plot showing dose‐dependent increase in IL‐1b expression in THP1‐derived macrophages in response to S1 protein.
• B
  S1 RBD domain does not activate THP1 cells. THP1 cells were stimulated with indicated protein (1 µg/ml) or PBS for 24 h. Gene expression was measured by qPCR.
• C
  SARS‐Cov‐2 spike protein activates mouse macrophages in vitro. Plots showing changes in the expression of cytokines in mouse Raw264.7 macrophages upon treatment with different domains of S1 subunit at 1 µg/ml for 24 h. Right, a schematic showing domain structure of full‐length S1 protein and RBD only.
• D
  The NTD is more divergent than the RBD of SARS‐Cov‐2. Plot shows sequence homology of NTD and RBD region of the SARS‐Cov‐2 spike protein with other coronaviruses.
• E
  Spike protein from endemic viruses does not activate THP1‐derived macrophages. THP1 cells were stimulated with indicated protein (1 µg/ml) or PBS for 24 h. Cytokine release was measured by Luminex.

Data information: in (A‐C, E), data are presented as means of 3 technical replicates. Error bars denote SEM.