RESUMEN
We report the identification of three structurally diverse compounds - compound 4, GC376, and MAC-5576 - as inhibitors of the SARS-CoV-2 3CL protease. Structures of each of these compounds in complex with the protease revealed strategies for further development, as well as general principles for designing SARS-CoV-2 3CL protease inhibitors. These compounds may therefore serve as leads for the basis of building effective SARS-CoV-2 3CL protease inhibitors.
Asunto(s)
Tratamiento Farmacológico de COVID-19 , Proteasas 3C de Coronavirus/antagonistas & inhibidores , SARS-CoV-2/efectos de los fármacos , Replicación Viral/efectos de los fármacos , Cristalografía por Rayos X , Evaluación Preclínica de Medicamentos , Humanos , Pirrolidinas/farmacología , Ácidos SulfónicosRESUMEN
There is an urgent need to create novel models using human disease-relevant cells to study severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) biology and to facilitate drug screening. Here, as SARS-CoV-2 primarily infects the respiratory tract, we developed a lung organoid model using human pluripotent stem cells (hPSC-LOs). The hPSC-LOs (particularly alveolar type-II-like cells) are permissive to SARS-CoV-2 infection, and showed robust induction of chemokines following SARS-CoV-2 infection, similar to what is seen in patients with COVID-19. Nearly 25% of these patients also have gastrointestinal manifestations, which are associated with worse COVID-19 outcomes1. We therefore also generated complementary hPSC-derived colonic organoids (hPSC-COs) to explore the response of colonic cells to SARS-CoV-2 infection. We found that multiple colonic cell types, especially enterocytes, express ACE2 and are permissive to SARS-CoV-2 infection. Using hPSC-LOs, we performed a high-throughput screen of drugs approved by the FDA (US Food and Drug Administration) and identified entry inhibitors of SARS-CoV-2, including imatinib, mycophenolic acid and quinacrine dihydrochloride. Treatment at physiologically relevant levels of these drugs significantly inhibited SARS-CoV-2 infection of both hPSC-LOs and hPSC-COs. Together, these data demonstrate that hPSC-LOs and hPSC-COs infected by SARS-CoV-2 can serve as disease models to study SARS-CoV-2 infection and provide a valuable resource for drug screening to identify candidate COVID-19 therapeutics.
Asunto(s)
Antivirales/farmacología , COVID-19/virología , Colon/citología , Evaluación Preclínica de Medicamentos/métodos , Pulmón/citología , Organoides/efectos de los fármacos , Organoides/virología , SARS-CoV-2/efectos de los fármacos , Animales , COVID-19/prevención & control , Colon/efectos de los fármacos , Colon/virología , Aprobación de Drogas , Femenino , Xenoinjertos/efectos de los fármacos , Humanos , Técnicas In Vitro , Pulmón/efectos de los fármacos , Pulmón/virología , Masculino , Ratones , Organoides/citología , Organoides/metabolismo , SARS-CoV-2/genética , Estados Unidos , United States Food and Drug Administration , Tropismo Viral , Internalización del Virus/efectos de los fármacos , Tratamiento Farmacológico de COVID-19RESUMEN
The rapid genetic drift of influenza virus hemagglutinin is an obstacle to vaccine efficacy. Previously, we found that the consensus hemagglutinin DNA vaccine (pCHA5) can only elicit moderate neutralization activities toward the H5N1 clade 2.1 and clade 2.3 viruses. Two approaches were thus taken to improve the protection broadness of CHA5. The first one was to include certain surface amino acids that are characteristic of clade 2.3 viruses to improve the protection profiles. When we immunized mice with CHA5 harboring individual mutations, the antibodies elicited by CHA5 containing P157S elicited higher neutralizing activity against the clade 2.3 viruses. Likewise, the viruses pseudotyped with hemagglutinin containing 157S became more susceptible to neutralization. The second approach was to update the consensus sequence with more recent H5N1 strains, generating a second-generation DNA vaccine pCHA5II. We showed that pCHA5II was able to elicit higher cross-neutralization activities against all H5N1 viruses. Comparison of the neutralization profiles of CHA5 and CHA5II, and the animal challenge studies, revealed that CHA5II induced the broadest protection profile. We concluded that CHA5II combined with electroporation delivery is a promising strategy to induce antibodies with broad cross-reactivities against divergent H5N1 influenza viruses.