Hepatitis A virus antigens (HAV antigens)

Hepatitis A virus (HAV) antigens, specifically the capsid proteins VP1, VP2, and VP3, serve as the primary targets for the host's adaptive immune system (StatPearls, 2023). These antigens are part of the HAV polyprotein, which is processed into structural proteins that form the viral capsid and non-structural proteins involved in replication (UniProt, P03300). The adaptive immune response to these antigens involves the generation of neutralizing antibodies and the activation of CD8+ T-cells, which are essential for viral clearance and long-term immunity (CDC, 2023). Vaccines against HAV utilize inactivated viral particles to present these antigens to the immune system, stimulating the production of protective IgG antibodies (WHO, 2022). In cases of recent exposure, passive immunization with human immune globulin provides immediate protection by supplying pre-formed antibodies against these viral antigens (Mayo Clinic, 2023). The interaction between these antigens and the immune system is the basis for diagnostic serology, where the presence of IgM or IgG antibodies indicates acute or past infection, respectively (NIH, 2023). Therapeutic strategies focus on prevention rather than direct antiviral treatment, as the immune system typically clears the infection spontaneously (StatPearls, 2023).

Other names

Hepatitis A virus polyproteinHAV capsid proteinsVP1VP2VP3VP4HAV structural proteins

Induction of active immunity through the production of neutralizing antibodies and T-cell activation following exposure to inactivated viral antigens; or provision of passive immunity via administration of exogenous antibodies.