TMPRSS2 and infection: The IC50 values varied depending on the form of infection and cell lines used, ranging from 1.4–5 μg/mL iota-carrageenan in the SSPL particles system to 2.1–10.3 μg/mL in A549-ACE2/TMPRSS2 cells, and 0.04–0.15 μg/mL in Calu-3 human lung cells infected with the SARS-CoV-2 variants.