NEO1 and Parkinson disease: While RGMa has previously been shown to be involved in the pathogenesis of neurological diseases, such as SCI (11, 12), MS (3, 13, 14), and PD (15, 16) through neuronal cell death, axonal damage, and inflammation promotion, the present study suggests that RGMa/NEO1 signaling is also altered in the spinal cord of patients with ALS and in animal models.