Hepatitis B virus antigens (HBV antigens)

Hepatitis B virus (HBV) antigens, primarily the surface antigen (HBsAg), core antigen (HBcAg), and e antigen (HBeAg), are the fundamental targets for the host immune system during infection (Liang, 2009, Hepatology). These proteins contain specific B-cell epitopes that elicit neutralizing antibodies, which prevent the virus from entering new hepatocytes, and T-cell epitopes that are recognized by CD4+ and CD8+ T cells to coordinate the destruction of infected cells (Bertoletti & Ferrari, 2012, Gut). In chronic HBV infection, the high viral load and persistent antigen exposure often lead to T-cell exhaustion, where the immune system fails to clear the virus (Seeger & Mason, 2000, Microbiol Mol Biol Rev). Therapeutic strategies focus on these epitopes to restore immune control, utilizing monoclonal antibodies like VIR-3434 to clear HBsAg or therapeutic vaccines like VTP-300 to stimulate T-cell responses (Lau et al., 2005, NEJM). The successful targeting of these epitopes is considered essential for achieving a functional cure, defined by the loss of HBsAg and long-term suppression of HBV DNA (WHO, 2023).

Other names

Hepatitis B virus proteinsHBV epitopesHBsAgHBcAgHBeAgHBV PolHBx

Induction of neutralizing antibodies by B-cell epitopes and activation of CD4+ and CD8+ T-cells by T-cell epitopes to clear infected hepatocytes and neutralize free virions.