Hepatitis B surface antigen-specific adaptive immune response

The Hepatitis B surface antigen-specific adaptive immune response denotes the processes by which the host immune system—primarily T cells and B cells—recognizes and mounts a defense against the Hepatitis B surface antigen (HBsAg), an outer envelope protein of HBV[2][4][8]. This response is critical for controlling virus propagation, clearing infected hepatocytes, and generating long-term immunological memory. CD8+ cytotoxic T lymphocytes mediate killing of infected cells, while CD4+ helper T cells and B cells orchestrate antibody production and immune modulation[2][4][6][8]. Anti-HBsAg antibodies (HBsAb) neutralize circulating virus particles, forming the basis for effective vaccine and serological protection[1][8]. Dysregulation of this response can lead to chronic infection, immune tolerance, and hepatitis B-associated liver pathology[3][6][8].

Antibody generation binds HBsAg, neutralizing and eliminating free virus. Effector T cell cytolytic response destroys HBV-infected cells. T cell-derived cytokines promote antiviral states and recruitment of other immune cells.