Hepatitis B core antibody (anti-HBc)

Hepatitis B core antibody (anti-HBc) is an immunoglobulin produced by the host immune system in response to the Hepatitis B core antigen (HBcAg), the protein making up the nucleocapsid of the Hepatitis B virus (HBV) (Liang, 2009, Hepatology). It is not a therapeutic target for pharmacological intervention but serves as a critical diagnostic biomarker for identifying current or past HBV infection (Mayo Clinic Laboratories). Total anti-HBc (IgM and IgG) typically appears at the onset of symptoms in acute hepatitis B and persists for life, making it a reliable indicator of viral exposure (Centers for Disease Control and Prevention). While it does not provide protective immunity—a role reserved for the surface antibody (anti-HBs)—its detection is vital for clinical decision-making. Specifically, the presence of anti-HBc is used to screen blood donors and to identify patients at risk of HBV reactivation when undergoing chemotherapy or treatment with B-cell depleting agents like rituximab (Perrillo et al., 2015, Hepatology). Although new drug classes such as capsid assembly modulators (CAMs) target the underlying core protein (HBcAg), the anti-HBc antibody itself remains a diagnostic tool rather than a site for drug action.

Other names

HBcAbHepatitis B virus core antibodyAnti-HBc IgGAnti-HBc IgM

Not applicable; anti-HBc is a diagnostic biomarker and host immune product, not a therapeutic target.