Peptide-Based Therapeutics in Autoimmune Diseases: Restoring Immune Balance Through Precision

Autoimmune diseases arise from the loss of antigen-specific tolerance, leading to chronic inflammation and tissue damage. Peptide-based therapeutics provide a precise strategy to restore immune balance by targeting autoreactive lymphocytes and antigen-presenting cells in tolerogenic contexts. These therapies induce regulatory T cells, modulate APC phenotypes, and can interfere with proinflammatory signaling. Advances in delivery technologies, including nanoparticles, lipid nanoparticles, hydrogels, and conjugates, improve peptide stability, co-deliver tolerogenic cues, and enable targeted antigen presentation. mRNA lipid nanoparticle platforms permit in situ expression of peptides or immunomodulatory molecules. Preclinical studies in models of type 1 diabetes, multiple sclerosis, and lupus demonstrate robust antigen-specific tolerance, while early-phase clinical trials show safety and mechanistic engagement. Insights from approved peptide therapies in allergy and other fields underscore the importance of epitope selection, delivery context, and biomarker-guided development. Collectively, these strategies suggest that rationally formulated, precisely targeted peptide therapeutics hold promise for achieving durable immune tolerance in autoimmune disease.