An epitope from Acanthamoeba castellanii that cross-react with proteolipid protein 139-151-reactive T cells induces autoimmune encephalomyelitis in SJL mice.

We report here that an epitope (aa, 83-95) derived from Acanthamoeba castellanii (ACA) induces clinical signs of experimental autoimmune encephalomyelitis (EAE) in SJL/J mice reminiscent of the disease induced with myelin proteolipid protein (PLP) 139-151. By using IA(s)/tetramers, we demonstrate that both ACA 83-95 and PLP 139-151 generate antigen-specific cross-reactive CD4 T cells and the T cells secrete identical patterns of cytokines and induce EAE with a similar severity. These results may provide insights into the pathogenesis of multiple sclerosis and ACA-induced granulomatous encephalitis.