Effective antigen-specific immunotherapy in the marmoset model of multiplesclerosis

Mature T cells initially respond to Ag by activation and expansion, but hig h and repeated doses of Ag cause programmed cell death and can suppress T c ell-mediated diseases in rodents, We evaluated repeated systemic Ag adminis tration In a marmoset model of experimental allergic encephalomyelitis that closely resembles the human disease multiple sclerosis, We found that trea tment with MP4, a chimeric, recombinant polypeptide containing human myelin basic protein and human proteolipid protein epitopes, prevented clinical s ymptoms and did not exacerbate disease, CNS lesions were also reduced as as sessed in vivo by magnetic resonance imaging, Thus, specific Ag-directed th erapy can be effective and nontoxic in primates.