MRI Estimation of Sub-Clinical Disease in Japanese Macaque Encephalomyelitis

William D. Rooney¹, Steven G. Kohama, Paul Wang, Jeffrey M. Njus, Scott W. Wong, Lawrence S. Sherman, Michael K. Axthelm, Gail H. Marracci, Dennis N. Bourdette

A spontaneously occurring demyelinating disease has recently been characterized in Japanese macaques (Macaca fuscata) at the Oregon National Regional Primate Center (ONPRC); the disease has been named "Japanese macaque encephalomyelitis" (JME). JME bears many similarities to human multiple sclerosis (MS) but has a much greater incidence. Typically, JME has an acute onset with rapid progression and is readily detected in affected individuals as impaired ambulation or motor skills during routine observation. The major finding of this study suggests that JME occurs with an even higher incidence that previously appreciated and with a disease severity that ranges from benign to fulminant. These observations have important implications for the development of a non-human primate model of MS based on a naturally occurring disease.