Aim. To review the most significant data concerning the immunological system importance in the pathogenesis and treatment of schizophrenia and depression.
Review: There are three aspects of the immunological system role in the pathogenesis of schizophrenia: contribution of the autoimmune process, cytokine regulation disturbances, and a pathogenic effect of viral infections. The studies carried out in depressed patients in the 1980s reported a reduction in the immunological system activity (particularly of cellular immunity). On the other hand, research findings obtained in the 1990s indicate a pathological activation of this system, with probably a major role of the cytokine system disturbances, especially of the so-called pro-inflammatory cytokines. Both experimental and clinical studies suggest an antiviral and immunomodulatory action of lithium salts. In the review some data are also presented pertaining to neuroimmunological aspects of the action of neuroleptic and antidepressant drugs, as well as their possible therapeutic effects in schizophrenia and depression via the immunological system.