What primarily causes the killing of liver cells infected with hepatitis B virus?

The killing of liver cells infected with hepatitis B virus is primarily due to the immune response, particularly the actions of cytotoxic T lymphocytes (CTLs). When hepatocytes are infected by the hepatitis B virus, they present viral antigens on their surface using major histocompatibility complex (MHC) class I molecules. Cytotoxic T lymphocytes recognize these viral antigens as foreign, leading them to target and destroy the infected liver cells.

While other processes might contribute to cell injury during a viral infection, the direct killing mechanism involving CTLs is critical in controlling the hepatitis B virus infection. The shut-off of cellular protein synthesis and intracytoplasmic accumulation of antigens are associated with the virus's biological activity but do not directly account for the death of the infected cells. Similarly, virus-induced chromosome changes may occur as a result of viral infection but are not the primary cause of cell death. The main driving force in eliminating infected cells is indeed the specific immune response, especially the cytotoxic T lymphocytes responding to the viral infection.