Recombinant human β-galactoside binding lectin suppresses clinical and histological signs of experimental autoimmune encephalomyelitis

Abstract Human placental tissue contains regulatory molecules that may prevent allo-sensitization. Recently, a 14 kDa β-galactoside binding protein with demonstrated immunoregulatory properties has been cloned using cDNA from human placenta and expressed in Escherichia coli . The present study assesses the ability of this r ecombinant i mmuno m odulatory l ectin (rIML-1), to prevent experimental autoimmune encephalomyelitis (EAE), a paralytic T cell-mediated disease directed against myelin basic protein (BP). Injection or rIML-1 into Lewis rats inhibited the induction of both clinical and histological signs of EAE, apparently by blocking sensitization of encephalitogenic BP-specific T cells and inducing BP-dependent suppressor cells. Because it is neither immunogenic nor toxic, rIML-1 may have application in humans, and would have distinct advantages over unselective cytotoxic immunosuppressive agents used currently in the treatment of autoimmune diseases and transplantation.