The invention features methods for the prevention or treatment of autoimmune disorders in humans. The methods include administering an autoantigen in combination with an oil-based carrier. Included are methods for the prevention and treatment of diabetes mellitus which include treating a patient with a diabetes type 1 autoantigen, e.g., human insulin B-chain or GAD65, and an oil-based carrier approved for human use. Also included are vaccines and kits for the treatment of diabetes mellitus.