Fibrin degradation products in post mortem brain tissue of schizophrenics: A possible marker for underlying inflammatory processes

Alterations in protein composition are often present in diseases of the central nervous system (CNS). Inflammatory processes causing these alterations have been suggested by many authors to underlie the cerebral disturbance in some cases of schizophrenia. In a previous study, two disease-associated additional polypeptides P1 and P2 could be detected in the cerebrospinal fluid (CSF) of 60 out of 123 (49%) schizophrenic patients. These polypeptides were identified as cleavage products of the beta-chain of fibrin(ogen), an acute-phase protein which is increased in inflammatory processes. Because investigations of brain tissue might better reflect the disease process than cerebrospinal fluid, we examined 6 post mortem brains (3 schizophrenics, 3 normal controls) for the presence of fibrin(ogen) and its cleavage products by two dimensional gel electrophoresis followed by immunoblotting. We detected fibrin(ogen) and its degradation products P1 and P2 in all schizophrenic brain tissue samples, but not in that from controls. These results are consistent with previous CSF observations and suggest that a CNS inflammatory process may be occurring in a subgroup of schizophrenic patients.