Hepatitis B Virus Surface Antigen (HBsAg) EIA

The GS HBsAg EIA 3.0 is a qualitative enzyme immunoassay for detection of Hepatitis B Surface Antigen (HBsAg) in human serum and plasma. It is indicated as a screening test for specimens from individual human donors, including donors of whole blood, blood components, and source plasma, and from other living donors. It is also intended for use in testing plasma and serum specimens to screen organ donors when specimens are obtained while the donor's heart is still beating. The assay is not intended for use on cord blood specimens.

About Hepatitis B Surface Antigen

Hepatitis B virus (HBV) is a major public health problem worldwide, with significant transmission of the virus occurring through the use of contaminated donor blood and plasma. Also of concern is the transmission of HBV and other infectious diseases through tissue transplantation.¹ Because the presence of circulating Hepatitis B Surface Antigen (HBsAg) is used to detect potentially infectious blood and plasma.² Enzyme immunoassays to detect HBsAg have replaced relatively insensitive gel diffusion methods and have been reported to have equivalent sensitivity to radioimmunoassay methods.³ The application of monoclonal antibodies for the detection of HBsAg has been previously reported.^4.5 The GS HBsAg EIA 3.0 is a third generation enzyme immunoassay, which uses mouse monoclonal antibodies to detect HBsAg in human serum or plasma specimens.

Specimens that are non-reactive when tested with the GS HBsAg EIA 3.0 are considered negative for HBsAg and need not be tested further. Reactive specimens should be retested, in duplicate, using the GS HBsAg EIA 3.0 to determine whether they are repeatedly reactive. A repeatedly reactive specimen should be confirmed by a licensed neutralization procedure utilizing human anti-HBs (GS HBsAg Confirmatory Assay 3.0). If the HBsAg in the specimen can be neutralized by the confirmatory procedure, the specimen is considered positive for HBsAg and need not be tested further.

Wells of the microwell strip plates are coated with mouse monoclonal antibody to HBsAg (anti-HBs). Serum or plasma and appropriate controls are added to the wells, and incubated with the bound antibody. If HBsAg is present, it will bind to the antibody and not be removed by washing. The strips are washed to remove any unbound material. Washing is followed by the addition of Conjugate Solution (peroxidase-conjugated mouse monoclonal antibodies directed against HBsAg). The Conjugate Solution will bind to the antibody-HBsAg complex, if present. Unbound conjugate is removed by a wash step. Next, Working TMB Solution is added to the plate and allowed to incubate. A blue or blue-green color develops in proportion to the amount of HBsAg present in the sample. The enzyme reaction is stopped by the addition of acid, which changes the blue-green color to yellow. The optical absorbance of specimens and controls is determined with a spectrophotometer set at 450 nm wavelength. Test performed by VRL Eurofins,  6933 S. Revere Parkway, Centennial, CO 80112. This test has been cleared or approved for diagnostic use by the U.S. Food and Drug Administration. See package insert for more information.