An antigen-less pro-vaccine for treating autoimmunity.

We have designed the first antigen-less pro-vaccine, named 8206, for treating autoimmune diseases. Composed of dexamethasone, rapamycin, and R848 at a mass ratio of 8:20:6, 8206 is a complete tolerogenic adjuvant that acts systemically to form an active vaccine in situ with endogenous pathogenic autoantigens. This active vaccine suppresses autoimmunity by expanding antigen-specific Treg cells in affected tissues. In a mouse model of atherosclerosis, 8206 successfully targeted all three analyzed pathogenic autoantigens (ApoB, HSP60, and HMGB1) and inhibited disease progression. These findings suggest that 8206 can potentially serve as a universal treatment vaccine for autoimmune diseases by eliminating the need for exogenous immunogens, with implications for broad applications in immunotherapy.