The aim of this study was to evaluate the sensitivity of the bioluminescence enzyme immunoassay for the detection of hepatitis B surface antigen (BLEIA®EIKEN HBsAg) and to compare the sensitivity with microparticle enzyme immunoassay (MEIA). Samples were collected during the early infection phase from six chimpanzees infected with hepatitis B virus (HBV) genotype A or genotype C. In the early infection phase, there was a direct correlation between HBV DNA and HBsAg until the appearance of anti-HBc and anti-HBs. The cut off value of BLEIA, 0.005 IU/mL, was estimated to correspond to 400 copies/mL. BLEIA detected HBsAg earlier than other methods. Therefore, the measurement of HBsAg by BLEIA is suggested to be useful for the investigation of HBV infection.
