Serum TNF-α, IL-10 and IL-2 in schizophrenic patients before and after treatment with risperidone and clozapine

Schizophrenia is a disorder of the executive function of both sensory and central nervous system. Recent studies suggest that immune mechanisms play a role in the pathophysiology of this disease. The variations in cytokine concentrations have been associated with psychopathology and treatment of schizophrenia.

To investigate the changes in serum concentrations of TNF-α, IL-10, and IL-2 in schizophrenic patients before and 40 days after treatment.

In a case-control study, 26 schizophrenic patients and 26 healthy individuals as a control group were enrolled. PANSS scale questionnaire was used for diagnosis and assessing the severity of the disease. All patients were then treated with risperidone or clozapine for 40 days. Serum concentrations of TNF-α, IL-10 and IL-2 were measured by ELISA before and after treatment in both groups. Paired t-test and Independent t-test were used for comparison of data.

Comparison of TNF-α and IL-10 concentrations in patients before and after treatment revealed a significance decrease of TNF-α and increase of IL-10 concentrations (p=0.002, and p=0.008, respectively). Serum concentrations of IL-2 were lower than the detection limit of assay and were not detectable. In comparison with healthy controls, serum concentrations of TNF-α in schizophrenic patients were higher, while IL-10 concentrations were lower before treatment although the differences were not significant (p=0.291 and p=0.375, respectively). There was no correlation between cytokine concentrations and the positive and negative scale (PANSS). Also no significant difference in the admission, relapses, and duration of illness before and after treatment was observed.

Increase of TNF-α and decrease of IL-10 may have an important role in psychopathology of schizophrenia.