Anti-JC virus antibody test

John Cunningham virus (JCV) is a human polyomavirus, a common environmental virus that has been infected in approximately 39-58% of the population and is tested positive for anti-JC virus antibodies. However, if the host's immune system is defective or suppressed, it may cause JC virus mutation and activation, and then cross the blood brain barrier to infect brain oligocytes and astrocytes, resulting in progressive multi-part leukoencephalopathy

Aquaporin 4 antibody test (AQP4 autoantibody)

Neuromyelitis optica (NMO), also known as Devic's syndrome, is a rare autoimmune demyelinating disease that occurs in the central nervous system, characterized by recurrent inflammation of the optic nerve and spinal cord, often leading to blindness or limb disability, and a poor prognosis. NMO-IgG (also known as AQP4 antibody) is a specific protein expressed in NMO patients and can be used as a reference for clinical diagnosis.