NOVEL PACKAGES OF VIRAL AND SELF-ANTIGENS ARE GENERATED DURING APOPTOSIS

Immune context is an essential determinant of the host response to pot ential autoantigens. The clustering of the autoantigens targeted in sy stemic lupus erythematosus within surface blebs of apoptotic cells gen erates high concentrations of autoantigen within discrete subcellular packages. We demonstrate here that when apoptosis is induced by Sindbi s virus infection, viral antigens and autoantigens cocluster exclusive ly in small surface blebs of apoptotic cells. The surface of these ble bs is rich in viral glycoproteins, and virions can be seen blebbing fr om their surface. We propose that these blebs of mixed foreign and sel f-origin define a novel immune context that may challenge self-toleran ce.