From these results, we may speculate that the lectin, CV-N, does not mimic ACE2. We further speculate that it instead may exert a conformational constraint on S-trimer structural dynamics (analogous to state-stabilizing inhibitors of HIV-1 ( )), and which may persist after repeated washing. As previously described, after 10 washes, both SARS-CoV-2 pseudovirus and spikenegative virus-like particles retained small amounts of residual CV-N (Supplemental Figure ). While this could represent lectin binding to non-spike glycoproteins inherited from producer cells, the possibility remains that remnant CV-N may stay bound to Spike on the Spikecontaining pseudoviruses and is at least partly responsible for the irreversible inactivation.