Fig. 4: CD163⁺ macrophage density was increased in high inflammation schizophrenia and ICAM1 correlated with peripheral immune cell marker expression.

A–F Examples of CD163 immunostaining (brown) from each inflammatory subgroup with Nissl counterstaining (blue). CD163⁺ macrophages surrounded blood vessels (black arrows) and were also found in the SEZ parenchyma (red arrows). The lateral ventricle and ependymal cell layer are on the left of each image. G CD163⁺ macrophage numbers per mm² were significantly increased in high inflammation schizophrenia compared to low inflammation controls. H ICAM1 mRNA expression positively correlated with all immune cell markers. Data are plotted relative to the mean of the low inflammation control group (100%) ± standard error of the mean. High inflammation controls are displayed as grey points but were not used in statistical analyses. BPD bipolar disorder, CTRL control, High high inflammation, Low low inflammation, LV lateral ventricle, SCZ schizophrenia, sr semi-partial correlation coefficient. *p < 0.05. Scale bar = 50 μm.