Views:3 Author:Site Editor Publish Time: 2020-04-08 Origin:Site
Since January 2020, the State Drug Administration has approved 7 companies' new coronavirus nucleic acid detection kits to be listed in accordance with the Medical Device Emergency Approval Procedure. Recently, many companies have designed and developed new coronavirus antigen / antibody detection reagents. These reagents are different from the previously approved nucleic acid detection reagents in terms of inspection principles, test methods, and intended uses. The following is a brief introduction.
What is an antigen detection reagent?
The new coronavirus gene encodes multiple structural proteins, such as N protein, E protein, and S protein. These proteins include multiple epitopes. Using the principle of specific binding of antigen and antibody, the presence of antigen can be detected by antibody, thereby directly Prove that the sample contains a new coronavirus. The applicable sample types of antigen detection reagents are generally samples of infected sites, such as pharyngeal swabs.
What are antibody detection reagents?
The above-mentioned antigen of the new coronavirus can be used as an immunogen. After the virus infects the human body, it stimulates the plasma cells to produce specific antibodies. Using the principle of specific binding of the antigen and the antibody, the presence of the antibody can be detected by the antigen, thereby indirectly proving that the human body is infected New coronavirus. The applicable sample types of antibody detection reagents are generally blood, including serum, plasma and whole blood.
The detected antibodies are mainly divided into IgM and IgG. There is currently no systematic study on the production and duration of these two types of antibodies against new coronaviruses. Normally, IgM antibodies are produced early. Once infected, they are produced quickly, with a short maintenance time, and disappear quickly. A positive test in the blood can be used as an indicator of early infection. IgG antibodies are produced late, maintained for a long time, and disappeared slowly. A positive test in the blood can be used as an indicator of infection and previous infection.