The Influence of Antipsychotic Treatment on the Activity of Abzymes Targeting Myelin and Levels of Inflammation Markers in Patients with Schizophrenia

Catalytic antibodies, or abzymes, are capable of not only binding but also hydrolyzing various proteins. Previously, an increase in the level of myelin basic protein (MBP)-hydrolyzing activity of antibodies was shown in patients with a number of neurological and mental disorders, including schizophrenia. Furthermore, antipsychotic therapy is known to induce a change in cytokine levels in patients with schizophrenia, which affects regulation of the immune response and inflammatory status. This study investigated the influence of typical and atypical antipsychotics on catalytic antibody activity and the 10 major pro- and anti-inflammatory serum cytokine levels. The study included 40 patients with schizophrenia: 15 treated with first-generation antipsychotics and 25 treated with atypical antipsychotics for 6 weeks. It was found that treatment with atypical antipsychotics changed the levels of some pro-inflammatory cytokines. Antipsychotic therapy also caused a significant decrease in MBP-hydrolyzing activity in patients with schizophrenia (p = 0.0002), and associations of catalytic activity with interleukins were observed.

Autoimmunity and immune system dysregulation in schizophrenia: IgGs from sera of patients hydrolyze myelin basic protein

Several different theories of schizophrenia (SCZ) were discussed; the causes of this disease are not yet clear. Using ELISA, it was shown that titers of autoantibodies against myelin basic protein (MBP) in SCZ patients are ~1.8-fold higher than in healthy individuals but 5.0-fold lower than in patients with multiple sclerosis. Several rigid criteria were checked to show that the MBP-hydrolyzing activity is an intrinsic property of SCZ IgGs. Approximately 82% electrophoretically homogeneous SCZ IgGs purified using several affinity sorbents including Sepharose with immobilized MBP hydrolyze specifically only MBP but not many other tested proteins. The average relative activity of IgGs from patients with negative symptoms was 2.5-fold higher than that of patients with positive symptoms of SCZ, and it increases with the duration of this pathology. It was shown that abzymes are the earliest statistically significant markers of many autoimmune pathologies. Our findings surmise that the immune systems of individual SCZ patients can generate a variety of anti-MBP abzymes with different catalytic properties, which can attack MBP of the myelin-proteolipid shell of axons. Therefore, autoimmune processes together with other mechanisms can play an important role in SCZ pathogenesis. MBP-hydrolyzing antibodies were previously detected in the blood of 80% to 90% of patients with systemic lupus erythematosus (SLE) and multiple sclerosis (MS). In addition, some similar neuropsychiatric indicators of disease common to SLE, MS, and SCZ were described in the literature. Thus, the destruction of the myelin sheath and the production of MBP-hydrolyzing antibodies can be a common phenomenon for some different diseases.