Antigen-specific adaptive immune response induction via in situ expression from self-replicating alphavirus-derived replicon RNA

The entry "Antigen-specific adaptive immune response induction via in situ expression from self-replicating alphavirus-derived replicon RNA" does not refer to a specific molecular target such as a defined receptor, enzyme, or transporter, but rather to a vaccine and gene delivery platform. Self-replicating alphavirus-derived replicon RNAs are synthetic, non-infectious RNAs based on alphavirus genomes that have been engineered to delete structural genes and encode therapeutic or immunogenic proteins of interest[1][4][5]. When delivered into cells, these replicons undergo RNA self-amplification and sustained expression of an encoded antigen, powerfully mimicking a viral infection and triggering both innate (type I interferon, cytokine production, antigen-presenting cell activation) and adaptive (antigen-specific antibodies and T cells) immune responses[4][5][6]. While they can be tailored to express different antigens and are investigated as platforms for infectious disease prophylaxis and cancer immunotherapy[3][4][5], they do not represent a single, canonically recognized biological “target” and should not be cataloged as such. Their main safety concerns involve vector immunity (limiting repeat administration), inflammatory reactogenicity, and manufacturing considerations. There is no conventional abbreviation, and this is not a specific molecular target but a platform technology or biological process[1][2][4][5][6].

Other names

Alphavirus replicon RNA vaccine platformSelf-amplifying RNA vaccine (saRNA)Alphavirus-derived self-replicating RNA

In situ protein antigen expression triggers innate immune sensors (e.g., Toll-like receptors, RIG-I); acts as its own adjuvant, inducing type I interferon and proinflammatory cytokine production; drives antigen presentation to T and B cells for adaptive immune induction; and prolonged antigen expression enhances humoral and cellular responses.