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The Frustrations of Being NMO AQP4 Negative

The symptoms that we now recognize as NMO were first described more than 100 years ago. However, without the right technology and testing, it was hard to separate NMO from other similar conditions, such as multiple sclerosis (MS).1

These diseases were originally thought to be one underlying condition with varying symptoms and severity. However, advancements in diagnosis and testing have allowed experts to find what makes NMO unique. One of these factors is the presence of specific antibodies. These are called AQP4 antibodies and MOG antibodies.1-4

What is AQP4?

AQP4 stands for aquaporin-4. It is a protein on the outside of certain brain cells. It controls water balance. Specifically, it controls how water moves in and out of cells. AQP4 can be found on cells in the brain, spinal cord, and along the nerve that controls vision (optic nerve).1,2,5,6

In the brain, AQP4 is found on cells called astrocytes. These play an important role in creating and maintaining the blood-brain barrier. This barrier protects the brain and spinal cord from many germs and toxins. Astrocytes also play a role in supporting nerve cells and communication between nerves. They help repair damage in the brain and provide nutrients. Astrocytes are the support cells of the central nervous system.5,6

Why it's frustrating

Without the presence of AQP4 antibodies, the diagnosis and treatment of NMO can be more complex. Aldelly explains her experiences in this video.


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