Diagnostic Tests

CLINICAL ASSOCIATIONS

Mitogen’s NMDA (NR1) Receptor assay is an autoimmune diagnostic test that detects autoantibodies to glutamate receptor (type NMDA). NMDA Receptor (N-methyl-D-aspartate receptor or NMDAR), is a protein found in nerve cells and it acts as both a glutamate receptor and ion channel protein. When NMDAR is bound by its target (glutamate and glycine) it becomes activated which then allows positively charged ions to flow through the cell membrane. This is a critical process for controlling synaptic plasticity, memory and learning, and the general development of the central nervous system.

Autoantibodies against glutamate receptors (type NMDA) are specific markers for anti-glutamate receptor (type NMDA) encephalitis, an inflammatory encephalopathic autoimmune disease. The antibodies are directed against an extracellular epitope of the receptor subunit NR1 and can be detected in serum or CSF. It is highly recommended to test paired CSF and serum samples. Typically CSF is tested first because of higher sensitivity. Rarely antibodies are detected in serum when CSF testing is negative.

Reference: H. E. Peery, G. S. Day, S. Dunn, M. J. Fritzler, H. Pruss, Souza C. De, A. Doja, K. Mossman, L. Resch, C. Xia, B. Sakic, L. Belbeck, and W. G. Foster. Anti-NMDA receptor encephalitis. The disorder, the diagnosis and the immunobiology. Autoimmun.Rev. 11:863-872, 2012.