Using a reverse genetic system, researchers mapped SARS-CoV-2 infection.

DOI:reverse genetic system in virology, usually refers to the cloning of the virus's full-length genome cDNA to the vector and the replication of modified sub-viruses in the cell, so as to achieve the goal of modifying the genetic characteristics of the virusBaric team is the ancestor of the development of coronavirus reverse technologyIn the latest study, they built an infectious clone of SARS-CoV-2 and a recombinant new coronavirus that expresses nano-luciferase (nLucerase), establishing a high-throughput, accurate neutralizing antibody detection methodspecifically, the researchers used different SARS-CoV-2 isolates to see how they effectively infected cultured cells in different parts of the human respiratory tractThey found a significant pattern of continuous change , SARS-CoV-2 , which showed a decreasing rate of infection in the human respiratory tract from the nasal cavity to the endothelial cells of the alveoliresearchers also found that ACE2 (the cell surface receptor used by the virus to enter cells) was expressed higher in the nasal epithelial cells, significantly higher than the throat, trachea, bronchial, end bronchial, and alveoli epithelial levelsThis difference may at least partly explain why the nasal epithelial cells are more susceptible to infectionresearchers further tested tmPRSS2 and Furin, two protein lysis enzymesThese enzymes are present in human cells, and SARS-CoV-2 uses them to reshape the necessary viral proteins and enter human cells for infectionIt turns out that when the levels of these enzymes rise, the ability to infect cells and replicate increasesthe epithelial cells of the nasal cavity in a person whoexpress the new coronavirus infection of GFP
CoVID-19 patients autopsied the new coronavirus and cilia cells, mucus secretion cells dye
the team mapped several cases of lung infection in patients who died of COVID-19 and found that even though SARS-CoV-2 had about 75% of the sequence ionity of SARS-CoV, previously described neutralizing antibodies against MERS-CoV and SARS-CoV would not neutraliseHowever, serum in two of the five SARS patients in 2002 showed low levels of serum but had significant ability to contract SARS-CoV-2 infection in neutralized and cultured cellsThese data suggest that people who have been exposed to other coronaviruses may carry other types of antibodies in their blood that can at least partially protect them from SARS-CoV-2 infection the summary of the cross-reaction of serum samples in SARS and COVID-19 patients, the study found that the recombinant virus prepared by reverse genetics was consistent with the replication level of wild virus in the cell line, and verified that protease TMPRSS2 and Furin had an enhanced effect on the replication of SARS-CoV-2 In addition, SARS-CoV-2 has a decreasing rate of infection in human respiratory tract sepsis from the nasal cavity to the endoscopic epithelial cells Cross-neutralized the production of ANTIbodies to SARS-CoV may be a low-probability event in people infected with the new crown virus these findings open up new directions for future research on SARS-CoV-2, which could guide drug development and reduce THE spread of COVID-19 References: The reverse viral genetic system explores SARS-CoV-2 respiratory habits and antibody neutralizing reactions.