CD81 and infection: This revealed, as expected, that infectious Jc1_mScarlet-2A was not able to spread in CD81-negative Huh7.5 cells (Figure 2A, left) whereas non-infectious Jc1_NS5A-mScarlet and Jc1_E2-mScarlet failed to induce spreading infection in both, control as well as CD81KO Huh7.5, confirming their loss of infectivity (Figure 2A, middle and right panel).