An Association of Hepatitis B (Australia) Antigen with Platelets

Hepatitis B surface antigen (HBsAg, Australia antigen) was detected by radioimmunoassay in freeze-thaw lysates of washed platelets from HBsAg carriers. Incubation of platelets from an HBsAg-negative person with medium containing HBsAg resulted in the platelets becoming positive for HBsAg. We suggest that platelets may phagocytize HBsAg-coated particles, and this may be an important transport mechanism for the hepatitis B agent.