Fig 1. Neutralization of SARS-CoV-2 pseudotyped lentivirus.

Neutralization assay with iota-carrageenan compared to neutralizing serum and negative serum. Approximately 7500 ACE2-HEK293 cells/well were infected with SARS-CoV-2 Spike pseudotyped lentivirus at an MOI of 0.1 (Luc reporter). Mock infected and mock treated infected cells served as negative control and positive control, respectively. 10 μg/ml iota-carrageenan and serum diluted 1:15 were incubated with the virus before infection. For infection, the virus/polymer or virus/serum inoculum was diluted with 5 volumes of medium. 48 hours after infection the infection efficiency was determined by measuring the luciferase activity. Luciferase data were corrected with metabolic data (Alamar blue) derived from a parallel plate with identical set-up. Data are normalized to % positive control and represent means of triplicates with standard deviation indicated.