IN-VIVO ROLE OF B-LYMPHOCYTES IN SOMATIC TRANSGENE IMMUNIZATION

Immunity generated by in vivo inoculation of plasmid DNA is a straight forward and potentially valuable new approach to immunization. Little is known about the type of cells involved, the various immunological a spects, and the destiny of the transgene, In this report, me describe a system in which immunity is the result of in vivo targeting of B lym phocytes. This nas accomplished using plasmid DNA encoding an immunogl obulin heavy-chain gene under the control of immunoglobulin promoter a nd enhancer elements, We show persistence of the transgene in splenic B lymphocytes for at least 3 months, i.e., the average life span of lo ng-lived B lymphocytes in the mouse, The transgene could not be detect ed in any other lymphoid or nonlymphoid organs over a period of 6 mont hs, We also established that the transgene is integrated in the host D NA, These studies bring new understanding to the events underlying the lit viva use of plasmid DNA, Moreover, the characteristics of this ne w approach make somatic transgene immunization a model system to study the immunogenicity of endogenous antigens in adult animals.