Fig. 2

Speculative etiology of anti-NMDA receptor encephalitis associated with tumors or viral infections. Tumors and viruses express NMDA receptors, leading to antigen uptake by antigen-presenting cells after cell death. Mature dendritic cells activate T cells, which induce B-cell differentiation into plasma cells, producing IgG autoantibodies. These autoantibodies damage neurons, mainly in the prefrontal cortex and hippocampus, affecting NMDA receptors. Autoantibodies alter receptor dynamics, impairing synaptic communication. This leads to reduced NMDA receptor density in synapses and decreased neuronal excitability