2019 Novel Coronavirus

How does SARS-CoV-2 Spread?

The virus is reportedly spreading from person-to-person in many parts of China and in some other countries by interacting with ACE2 from mucous membrane of eye, mouth and nose. On Jan. 30, the Centers for Disease Control and Prevention (CDC) identified the first case of person-to-person spread in the United States.

In terms of how one would catch the virus, the CDC says that human coronaviruses are most commonly spread between an infected person and others via:

• The air (from viral particles from a cough or sneeze);
• Close personal contact (touching or shaking hands);
• An object or surface with viral particles on it (then touching your mouth, nose or eyes before washing your hands);
• And rarely from fecal contamination.

The Latest Progression of SARS-CoV-2 Research

In this section, we collect several latest progression of SARS-CoV-2 research, including the mechanism of SARS-CoV-2 infection, the detection methods of SARS-CoV-2, the targets of SARS-CoV-2 invasion, etc.

• As you know, the SARS-CoV-2 uses an RNA-dependent RNA polymerase (RdRp) for the replication of its genome and the transcription of its genes. On April 27, 2020, researchers led by Patrick Cramer of the Max Planck Institute for Biophysical Chemistry in Göttingen, Germany published a study on the bioRxiv entitled “Structure of replicating SARS-CoV-2 polymerase”. They determined the three-dimensional structure of the SARS-CoV-2 polymerase. The results of this study will allow for a detailed analysis of the inhibitory mechanisms used by antivirals such as remdesivir, which is currently in clinical trials for the treatment of coronavirus disease 2019 (COVID-19).

• For the term of SARS-CoV-2-host interactome targets, except for ACE2 and TMPRSS2, on May 14, 2020, researchers from Central South University and China Agricultural University published a study entitled "The MERS-CoV receptor DPP4 as a candidate binding target of the SARS-CoV-2 spike" online on iScience. They revealed that SARS-CoV-2 spike (hereinafter referred to as SARS-CoV-2-S) receptor-binding domain (RBD) has a potentially high affinity to DPP4 by bioinformatics methods combining crystal structure-based human-viral interaction prediction and protein docking. And SARS-CoV-2-S/DPP4 binding shares key DPP4 residues with that of MERS-CoV-S/DPP4. In addition, compared with SARS-CoV-S, E484 insertion and adjacent substitutions are critical for the DPP4-binding ability of SARS-CoV-2-S. This potential utilization of DPP4 as a binding target for SARS-CoV-2 may provide new insights into the viral pathogenesis and help develop monitoring and treatment strategy for addressing the challenges of COVID-19.

• On May 26, 2020, two latest studies completed by Chinese scientists were published on Nature. The two studies are about isolated highly active neutralizing antibodies specific for SARS-CoV-2 from patients.

  One of the studies was completed in cooperation with the Institute of Microbiology, Chinese Academy of Sciences, Wuhan Institute of Virology, Chinese Academy of Sciences and Beijing Ditan Hospital and entitled "A human neutralizing antibody targets the receptor binding site of SARS-CoV-2", In this study, the researchers reported the isolation of two specific human monoclonal antibodies (MAbs) from a convalescent COVID-19 patient: CA1 and CB6. The researchers found that CA1 and CB6 showed strong SARS-CoV-2 specific neutralizing activity against SARS-CoV-2 in vitro. Moreover, structural studies have shown that CB6 can recognize epitopes that overlap with the ACE2 binding site in the SARS-CoV-2 receptor binding domain (RBD), thereby interfering through steric hindrance and direct interface-residue competition Virus/receptor interaction.

  Another study was completed in collaboration with multiple research teams at Tsinghua University and entitled "Human neutralizing antibodies elicited by SARS-CoV-2 infection". In this study, the researchers reported the isolation and identification of 206 RBD-specific monoclonal antibodies from single B cells of 8 SARS-CoV-2 infected individuals. And the researchers identified antibodies with potent anti-SARS-CoV-2 neutralizing activity that are related to ACE2's ability to compete with RBD.

• On June 6, 2020, researchers from multiple institutions in China jointly published a study titled "Development of an inactivated vaccine candidate, BBIBP-CorV, with potent protection against SARS-CoV-2" on Cell, including Beijing Biological Products Institute Co., Ltd., China Center for Disease Control and Prevention, Peking Union Medical College, National Food and Drug Administration and Tsinghua University. They reported the pilot-scale production of an inactivated SARS-CoV-2 vaccine candidate (BBIBP-CorV) that induces high levels of neutralizing antibodies titers in mice, rats, guinea pigs, rabbits and nonhuman primates to provide protection against SARS-CoV-2. In addition, BBIBP-CorV showed efficient productivity and good genetic stability in vaccine manufacture. These results support for the further evaluation of BBIBP-CorV to enter a clinical trial.