Analysis of auto-antibodies in schizophrenia

Objectives: Schizophrenia is a neuropsychiatric disorder with a complex etiology and pathogenesis. While symptomatic treatment is available, there are no treatments that target the biological disease mechanisms. Recently, autoantibodies to neuronal cell surface antigens have been identified in patients with schizophrenia. Autoimmunity is affecting nearly 10% of the general population and its clinical spectrum varies from endocrine, musculoskeletal to neuropsychiatric syndromes. Since autoimmune patients frequently suffer from more than one autoimmune disease, we analyzed common autoantibodies as disease markers (or risk factors) to test the hypothesis that schizophrenia is correlated to autoimmunity. Methods: We tested sera from 232 schizophrenia, bipolar disorder and myasthenia gravis patients and healthy controls for the presence of autoantibodies by ELISA and immunofluorescence. The assays included: anti-nuclear antibodies (ANA), double-stranded DNA (dsDNA), and ribosomal P protein (RPP). ANA IFA screening was performed on ImmunGlo HEp-2 slides and the acquisition of images and interpretation of patterns was performed on the Immco i-Sight automated imaging system. Results: Prevalence of anti-dsDNA autoantibodies was found to be overall relatively high and to significantly differ between disease and control groups. Schizoaffective patients had highest titers of anti-dsDNA autoantibodies. The autoantibody titer anti-RPP differs significantly between the groups. Paranoid and disorganized patients had highest titers of anti-RPP autoantibodies. No significant difference was detected in the presence of ANA autoantibodies in the different study groups. Conclusions: We confirmed that a subgroup of schizophrenia patients had increased levels of autoantibodies. These findings are the first step to improve diagnosis and possibly treatment of schizophrenic patients with autoimmune etiology. Currently, control sera are being tested to match the sample size and the age and sex distribution of the disease group.