Modular mRNA platform for in vivo antigen-specific immune tolerance

Immune-mediated diseases such as autoimmunity and allergy arise from dysregulated antigen-specific responses, yet current therapies largely rely on broad immunosuppression and rarely re-establish durable, antigen-selective tolerance. Here we introduce Tol-mRNA, a modular tolerogenic mRNA platform designed to deliver multiple immune-regulatory signals in vivo to program antigen-specific tolerance. Tol-mRNA co-encodes an antigen together with two complementary regulatory cues, PD-L1 and TGF-{beta}, enabling coordinated antigen presentation and tolerogenic signaling that robustly induces antigen-specific Tregs and suppresses pathogenic effector responses. In murine disease models, Tol-mRNA conferred therapeutic benefit across distinct immune pathologies. In experimental autoimmune encephalomyelitis, Tol-mRNA ameliorated clinical disease and reduced inflammatory immune activation. In an ovalbumin-driven food allergy model, Tol-mRNA prevented allergic symptoms and dampened type 2 inflammation. Extending these findings to humans, Tol-mRNA demonstrated potent, antigen-dependent immunosuppressive activity and a strong capacity to promote antigen-specific Treg induction in human immune settings. Collectively, these results establish Tol-mRNA as a scalable and versatile approach to reprogram antigen-specific immunity and support its development as a next-generation therapeutic modality for immune-mediated diseases.