Synthetic heparan sulfate mimics based on chitosan derivatives show broad-spectrum antiviral activity.

Enveloped viruses enter cells by binding to receptors present on host cell membranes, which trigger internalization and membrane fusion. For many viruses, this either directly or indirectly involves interaction with membrane-anchored carbohydrates, such as heparan sulfate, providing a potential target for a broad-spectrum antiviral approach. Based on this hypothesis, we screened a library of functionalized chitosan sulfates that mimic heparan sulfate in cellular membranes for inhibition of SARS-CoV-2 and respiratory syncytial virus (RSV) entry.