Automated Immunohistochemical Analysis of the Orbitofrontal Cortex in Patients with Schizophrenia, Bipolar Disorder and Major Depressive Disorde

Previous studies have found evidence for orbitofrontal cortex (OFC) pathology in major depressive disorder (MDD), bipolar disorder (BP) and to a lesser extent schizophrenia (SCZ). However, given that the OFC is a large heterogeneous area, it is difficult to assess how findings from small subareas translate to the entire region. The aim of this thesis is to analyze the entire OFC in patients with MDD, BP and SCZ. Using a novel approach with layer-specific immunohistochemical markers and an automated counting protocol, we were able to analyze the cortical width, cell density, cell area and distance from pia in the entire OFC of 60 post-mortem brain samples (15 control, 15 MDD, 15 BP, 15 SCZ). We did not find strongly significant differences between patients and control subjects. Our findings suggest that inconsistencies in the literature may arise from sampling only small areas of the cortex in a limited number of subjects.