Medical Diagnosis Exams

Hepatitis B core antigen (HBcAg) is a non‑glycosylated protein (p22) which forms the nucleocapsid (virus core) of the hepatitis B virus.

During an infection with the hepatitis B virus, antibodies to HBcAg are generally formed, which often persist for life. Anti‑HBc appears shortly after the onset of infection with hepatitis B virus and can usually be detected in serum soon after the appearance of HBsAg.

IgM antibodies to HBcAg occur in serum during proliferation of active hepatitis B virus and can still be detected weeks to months after viral proliferation has ceased. High anti‑HBc IgM concentrations can be found in acute hepatitis B and in attacks during chronic hepatitis B.