PROTRACTED, RELAPSING AND DEMYELINATING EXPERIMENTAL AUTOIMMUNE ENCEPHALOMYELITIS IN DA RATS IMMUNIZED WITH SYNGENEIC SPINAL-CORD AND INCOMPLETE FREUNDS-ADJUVANT

Experimental autoimmune encephalomyelitis (EAE) is a model for multipl e sclerosis (MS). However, MS is a chronic, relapsing and demyelinatin g disease, whereas EAE in rats is typically a brief and monophasic dis order showing little demyelination. We demonstrate here that DA rats d evelop severe, protracted and relapsing EAE (SPR-EAE) after a subcutan eous immunization at the tail base with syngeneic spinal cord and inco mplete Freund's adjuvant (IFA). The neurological deficits were accompa nied by demyelinating inflammatory lesions in the spinal cord, with in filtrating T lymphocytes and perivascular deposition of immunoglobulin s and complement. The induction of SPR-EAE was associated with humoral autoreactivity to myelin oligodendrocyte glycoprotein (MOG) and cellu lar autoreactivity to the rat myelin basic protein (MBP) peptides 69-8 7 and 87-101. These two peptides, as well as whole rat MBP, were encep halitogenic. In conclusion, we believe that the presently described de myelinating SPR-EAE represents a useful model for MS.