<prompt> A 40-year-old man complains of having yellow skin and sclerae, abdominal tenderness, and dark urine. Physical examination reveals jaundice and mild hepatomegaly Laboratory studies demonstrate elevated serum bilirubin 3.1 mgdL, decreased serum albumin 2.5 gdL, and prolonged prothrombin time 17 seconds. Serologic tests reveal antibodies to hepatitis B core antigen IgG anti-HBcAg. The serum is also positive for HBsAg and HBeAg. What glycoprotein on virally infected hepatocytes provides a target for cell-mediated cytotoxicity in the patient?CD4CD8Class I HLA moleculesClass II HLA molecules  <response>: Class I HLA molecules. Class I molecules of the major histocompatibility complex present foreign peptides and are recognized by cytotoxic T lymphocytes during graft rejection or during cell-mediated killing of virus-infected cells. All tissues express class I molecules, whereas class II molecules choice D are displayed primarily on macrophages and B lymphocytes. CD4 and CD8 choices A and B are cell surface markers of helper and killer T lymphocytes, respectively. GlyCAM-1 choice E facilitates lymphocyte recirculation by providing a receptor for leukocyte attachment to high endothelial venules.Diagnosis: Chronic hepatitis B 