Therapeutic effects of dipyridamole on COVID-19 patients with coagulation dysfunction

The human coronavirus HCoV-19 infection can cause acute respiratory distress syndrome (ARDS), hypercoagulability, hypertension, extrapulmonary multiorgan dysfunction. Effective antiviral and anti-coagulation agents with safe clinical profiles are urgently needed to improve the overall prognosis. We screened an FDA approved drug library and found that an anticoagulant agent dipyridamole (DIP) suppressed HCoV-19 replication at an EC50 of 100 nM in vitro. It also elicited potent type I interferon responses and ameliorated lung pathology in a viral pneumonia model. In analysis of twelve HCoV-19 infected patients with prophylactic anti-coagulation therapy, we found that DIP supplementation was associated with significantly increased platelet and lymphocyte counts and decreased D-dimer levels in comparison to control patients. Two weeks after initiation of DIP treatment, 3 of the 6 severe cases (60%) and all 4 of the mild cases (100%) were discharged from the hospital. One critically ill patient with extremely high levels of D-dimer and lymphopenia at the time of receiving DIP passed away. All other patients were in clinical remission. In summary, HCoV-19 infected patients could potentially benefit from DIP adjunctive therapy by reducing viral replication, suppressing hypercoagulability and enhancing immune recovery. Larger scale clinical trials of DIP are needed to validate these therapeutic effects.

ACE2 expression by colonic epithelial cells is associated with viral infection, immunity and energy metabolism

Respiratory disease caused by the 2019 novel coronavirus (2019-nCoV) pneumonia first emerged in Wuhan, Hubei Province, China, in December 2019 and spread rapidly to other provinces and other countries. Angiotensin-converting enzyme 2 (ACE2) is the receptor for SARS-CoV and has been suggested to be also the receptor for 2019-nCoV. Paradoxically, ACE2 expression in the lung protects mice from SARS-CoV spike protein induced lung injury by attenuating the renin-angiotensin system. In the intestine, ACE2 also suppresses intestinal inflammation by maintaining amino acid homeostasis, antimicrobial peptide expression and ecology of the gut microbiome. Upon analysis of single cell-RNA sequencing data from control subjects and those with colitis or inflammatory bowel disease (IBD), we found that ACE2 expression in the colonocytes was positively associated with genes regulating viral infection, innate and cellular immunity, but was negatively associated with viral transcription, protein translation, humoral immunity, phagocytosis and complement activation. In summary, we suggest that ACE2 may play dual roles in mediating the susceptibility and immunity of 2019-nCoV infection.

Characterization of Synonymous Codon Usage Bias in the Pseudorabies Virus US1 Gene / 中国病毒学·英文版

In the present study,we examined the codon usage bias between pseudorabies virus (PRV) US1 gene and the US1-like genes of 20 reference alphaherpesviruses.Comparative analysis showed noticeable disparities of the synonymous codon usage bias in the 21 alphaherpesviruses,indicated by codon adaptation index,effective number of codons (ENc) and GC3s value.The codon usage pattern of PRV US1 gene was phylogenetically conserved and similar to that of the US1-like genes of the genus Varicellovirus of alphaherpesvirus,with a strong bias towards the codons with C and G at the third codon position.Cluster analysis of codon usage pattern of PRV US1 gene with its reference alphaherpesviruses demonstrated that the codon usage bias of US1-like genes of 21 alphaherpesviruses had a very close relation with their gene functions.ENc-plot revealed that the genetic heterogeneity in PRV US1 gene and the 20 reference alphaherpesviruses was constrained by G+C content,as well as the gene length.In addition,comparison of codon preferences in the US1 gene of PRV with those of E.coli,yeast and human revealed that there were 50 codons showing distinct usage differences between PRV and yeast,49 between PRV and human,but 48 between PRV and E.coli.Although there were slightly fewer differences in codon usages between E.coli and PRV,the difference is unlikely to be statistically significant,and experimental studies are necessary to establish the most suitable expression system for PRV US1.In conclusion,these results may improve our understanding of the evolution,pathogenesis and functional studies of PRV,as well as contributing to the area of herpesvirus research or even studies with other viruses.