AbstractTo induce oral tolerance in multiple sclerosis treatment, we proposed to use the predigested protein of pig spinal cord. The most biologically active composition was obtained from the hydrolysis of an undenaturated homogenate of proteins digested with pepsin. Feeding the rats with our preparation, before or after immunization with MS antigens, strongly reduced development of the experimental autoimmune encephalomyelitis (EAE). The biological results obtained in animals suggest that the developed method of induction of the oral tolerance should be effective in human treatment, at least as a support mechanism in combination with other treatment methods.