Hepatitis B virus core antigen and surface antigen (HBcAg and HBsAg)

Hepatitis B virus core antigen (HBcAg) and hepatitis B virus surface antigen (HBsAg) are structural proteins of the hepatitis B virus (HBV). HBcAg forms the nucleocapsid, which houses the viral genome, and is critical for capsid assembly and genome packaging. HBsAg is an integral membrane glycoprotein forming the viral envelope and mediates attachment and entry into hepatocytes via the sodium taurocholate co-transporting polypeptide (NTCP) receptor[1][2][4]. HBsAg is secreted abundantly as non-infectious subviral particles, acting as decoys to evade immune detection. Both proteins are key diagnostic markers in clinical hepatitis B management: HBsAg indicates current infection, while HBcAg elicits a strong immune response, producing detectable antibodies. Therapeutically, these antigens are important vaccine and drug targets, but are typically referenced and targeted separately due to distinct structures, genetics, and clinical implications[1][2][3][4].\n\nNote:\n- is_incorrect is true because "Hepatitis B virus core antigen and surface antigen" combines two distinct molecular entities (core antigen and surface antigen) typically treated individually for biomedical and clinical purposes. Each plays a different role in the virus life cycle, immune recognition, and as a drug or vaccine target. Their merger in a single record is non-standard in biomedical nomenclature[1][2][4].

Other names

HBcAg (Hepatitis B core antigen)HBsAg (Hepatitis B surface antigen)Small/Medium/Large HBsAg (S-HBsAg, M-HBsAg, L-HBsAg)Hepatitis B capsid protein (for HBcAg)Surface antigen of hepatitis B virus (for HBsAg)

Inhibition of HBV DNA synthesis indirectly reduces HBcAg and HBsAg production; Immune modulation leads to enhanced clearance of HBsAg and HBcAg expressing cells.