Previous HIV-1 studies with lectin-derived entry inhibitor constructs have demonstrated irreversible inactivation of pseudovirus by lysis and membrane disruption , prompting similar evaluations here with the most active lectin, CV-N. SARS-CoV-2 pseudovirus was incubated with serial dilutions of CV-N, pelleted, and the supernatant tested for p24 released from lysed pseudovirus. Detected leakage was limited and dose-dependent (Supplemental Figure ). Of note, in previous studies where HIV-1 lysis was observed, p24 release occurred as an apparent result of disturbing the metastable structure of the HIV-1 Env spike, and causing conformational rearrangement and irreversible inactivation of spike before target cell encounter . We therefore explored this latter possibility for SARS-CoV-2 by examining the viruses after stringent washouts following lectin exposure, before target cell infection. Indeed, we observed that CV-N-treatment irreversibly inactivates SARS-CoV-2 pseudovirus, with an IC 50 of 242.2±191.6 nM (Figure ). Briefly, pseudovirus and serial dilutions of CV-N were coincubated for 2 hours at 37 °C, then separated from lectin (Figure ) by repeated resuspension and filtration through a 100 kDa centrifugal concentrator (10 wash cycles) before addition of the virus to HEK293T ACE2 cells. Samples from each wash were saved and evaluated by Western Blot to determine the extent of residual CV-N after washes. Although the wash flowthroughs indicated that all unbound lectin was removed from the virus, small amounts of residual lectin were observed in both the washed virus sample and washed spike-negative virus-like particles (Supplemental Figure ).