Hepatitis B virus epitope-specific CD4-positive and CD8-positive T cells (HBV-specific T cells)

Hepatitis B virus (HBV) epitope-specific CD4-positive and CD8-positive T cells are the primary mediators of the adaptive immune response against HBV infection (Bertoletti & Ferrari, 2012, Nature Reviews Gastroenterology & Hepatology). CD8+ T cells, or cytotoxic T lymphocytes (CTLs), recognize viral epitopes presented on the surface of infected hepatocytes via MHC class I molecules and induce apoptosis or non-cytolytic viral clearance through cytokine secretion (Maini & Pallett, 2018, Journal of Hepatology). CD4+ T cells provide essential help by secreting cytokines like IL-2 and IFN-gamma, which are necessary for the maintenance of CD8+ T cell memory and the induction of high-affinity antibody responses by B cells (Gehring & Protzer, 2019, Gastroenterology). In chronic hepatitis B (CHB), these T cells typically exhibit an exhausted phenotype characterized by poor proliferative capacity, diminished cytokine production, and high expression of inhibitory receptors such as PD-1, CTLA-4, and TIM-3 (Ye et al., 2015, Nature Communications). Therapeutic interventions, including therapeutic vaccines (e.g., VTP-300, BRII-179), checkpoint inhibitors, and adoptive T-cell transfers, are designed to restore or supplement these T-cell populations to achieve functional cure, defined by the loss of hepatitis B surface antigen (HBsAg) (Yuen et al., 2021, Journal of Hepatology). A significant challenge in targeting these cells is the risk of immune-mediated liver injury, as the destruction of a large number of infected hepatocytes can lead to severe alanine aminotransferase (ALT) flares and potential liver failure (Bertoletti & Le Bert, 2020, Journal of Hepatology).

Other names

HBV-specific T lymphocytesHepatitis B virus-specific T cellsHBV-reactive T cellsHBV-specific CD4+ and CD8+ T cells

Enhancement of viral-specific immune surveillance through the induction, expansion, or rejuvenation of T cells capable of recognizing HBV-infected cells and secreting antiviral cytokines.