Antibody-like proteins that capture and neutralize SARS-CoV-2

To combat severe acute respiratory syndrome-related coronavirus 2 (SARS-CoV-2) and any unknown emerging pathogens in the future, the development of a rapid and effective method to generate high-affinity antibodies or antibody-like proteins is of critical importance. We here report high-speed in vitro selection of multiple high-affinity antibody-like proteins against various targets including the SARS-CoV-2 spike protein. The sequences of monobodies against the SARS-CoV-2 spike protein were successfully procured within only 4 days. Furthermore, the obtained monobody efficiently captured SARS-CoV-2 particles from the nasal swab samples of patients and exhibited a high neutralizing activity against SARS-CoV-2 infection (half-maximal inhibitory concentration, 0.5 nanomolar). High-speed in vitro selection of antibody-like proteins is a promising method for rapid development of a detection method for, and of a neutralizing protein against, a virus responsible for an ongoing, and possibly a future, pandemic.

Does the concomitant intra-arterial injection of asialoerythropoietin and edaravone mitigate ischaemic mucosal damage after acute superior mesenteric artery thromboembolism in a rabbit autologous fibrin clot model?

To increase the survival rate of patients with acute superior mesenteric artery thromboembolism (ASMAT) treated by catheter thrombolysis, we examined the effects of delivering edaravone and asialoerythropoietin, agents with tissue-protective activities, using a rabbit autologous fibrin clot ASMAT model. Japanese white rabbits (n=32) were randomly separated into four equal groups. 45 min after introducing autologous fibrin clot, Group U received urokinase and heparin; Group E received urokinase and heparin plus edaravone; Group A received urokinase and heparin plus asialoerythropoietin; and Group EA received urokinase, heparin and edaravone plus asialoerythropoietin via a catheter. The intestines were removed 6 h later and intestinal mucosal damage was scored using the Park's injury score. Survival time was assessed. Average mucosal injury was 5.78+/-1.52 (Group U), 2.88+/-0.72 (Group E), 1.90+/-1.23 (Group A) and 1.18+/-1.25 (Group EA). The degree of mucosal injury was significantly lower in Group EA than in Groups U and E (p<0.05). Conversely, there was no significant difference between Group A and Group EA, or between Group A and Group E. The survival times were 31.50+/-13.30 h (Group U), 51.00+/-24.74 h (Group E), 48.00+/-16.97 h (Group A) and 82+/-51.07 h (Group EA); the difference among the four groups was not significant. In conclusion, the concomitant administration of asialoerythropoietin and edaravone reduced mucosal membrane injury significantly compared with edaravone alone. However, to improve the survival of ASMAT rabbit models, the delivery of an appropriate dose of asialoerythropoietin is required, together with the development of methods to assess peripheral recanalisation.