PROS1 and infection: When we tested three representative plasma samples for unspecific pseudovirus inhibition, they all uniformly inhibited the infection of lentiviruses pseudotyped by SARS-CoV-2 (Wuhan) spike, including two pseudotyped by vesicular stomatitis virus G protein (VSV-G) and murine leukemia virus envelope (MuLV), which are of zoonotic extraction (Supplementary Figure S1).