In the early stage of hepatitis B infection, HBsAg appears first, followed by surface antibody (HBsAb). For neutralizing the antigen, an antigen-antibody immune complex is formed. Anti- HBs is an antibody against the antigen on the HBV shell surface, which can prevent HBV from crossing the cell membrane and entering new liver cells and neutralize HBV infection, thereby protecting the body. Therefore, the presence of hepatitis B surface antibody proves that immunity is developed in the body. Hepatitis B surface antibody may be produced after natural HBV infection or hepatitis B vaccination. The concentration of hepatitis B surface antibody reflects the antibody titer. In case of too low level of hepatitis B surface antibody titer (less than 10 mIU/mL), the antibody would lose its protective effect, followed by infection with hepatitis B virus. A titer of hepatitis B surface antibody greater than 10 mIU/mL indicates that there are protective antibodies in the body, which means the ability to prevent infection with hepatitis B virus. The higher the hepatitis B surface antibody titer, the better the protective effect, and the longer the protection lasts
Intended Use
This kit is used to quantitatively detect the antibody to hepatitis B virus surface antigen (HBsAb) in human serum and plasma.
Principle
This reagent is based on the double-antigen sandwich principle. The magnetic microparticles are coated with recombinant hepatitis B surface antigen. With the sample to be tested, the reaction diluent and the magnetic microparticles pooled, if the sample contains anti-HBs, the HBsAb in the incubated sample specifically recognizes and binds to HBsAg to form a solidified complex of “magnetic microparticles-antigen-antibody”. The unbound antibody is removed by washing, and then acridinium ester labeled HBsAg is added to form a sandwich complex of antigen-antibody-antigen with labeling; pre-trigger solution and trigger solution are added to the reaction complex, and acridinium ester catalyzes chemiluminescence to generate a light signal. The concentration of anti-HBs in the sample is proportional to the luminescence value measured by the luminometer. The HBsAb content in the sample is calculated by the calibration curve.
Storage
The kit should be stored upright, not upside down or horizontally. Store at 2–8°C with a validity period of 12 months.