Rare presence of autoantibodies targeting to NMDA and GABAA receptors in schizophrenia patients

Accumulating evidence suggests that the pathology of some psychiatric symptoms may relate to autoantibodies against various neuronal surface antigens, such as NMDA receptors (NMDARs) or inhibitory GABAA receptors (GABAARs). However, it is unclear whether the plasma of patients with schizophrenia contains autoantibodies targeting to NMDARs or GABAARs.Serum samples of 293 patients with schizophrenia were analyzed using a combination of live-cell-based assay (CBA) and immunostaining on primary neurons to quantify the positive rate of autoantibodies targeting NMDARs or GABAARs.Only one sample was found positive for anti-NMDAR autoantibodies, and no surface autoantibodies against GABAARs were found. No obvious difference in clinical manifestations was observed between the patients with positive and negative anti-NMDAR autoantibodies.Our results suggest that autoantibodies against NMDARs or GABAARs may affect only a small group of patients with schizophrenia, and the rates of these autoantibodies are lower than reported in prior work. It would be interesting to perform studies with psychotic disorder instead of schizophrenia to determine whether NMDAR or GABAAR autoantibody can be used as a biomarker to provide a new avenue for immunomodulatory therapy.