The group of patients with abscesses included 10 cases with abscess in the deep brain and 27 in the superficial brain. The samples were fixed with 10% neutral buffered formalin and further embedded in paraffin. Antigen retrieval was facilitated by heat and endogenous peroxidases were neutralized with 3% hydrogen peroxide in a routine fashion. Primary antibodies against CD68 (anti-CD68 antibody; 1:100; cat. no. ab125212; Abcam) were applied overnight at 4˚C. According to the manufacturer's protocol, the Poly-HRP Anti-Mouse/Rabbit IgG Detection System (cat. no. PV-9000; Zhongshan Goldenbridge-Bio) was employed with incubation for 30 min at 37˚C. The cutoff value was 10% for CD68. This approach was identical to that used in a previous study by our group (22 (link)).
The samples were examined using a Nanozoomer Digital Pathology (NDP; Hamamatsu Photonics; magnification, x100), which was used to identify five regions (hot spots) with the highest density of stained CD68+ macrophages or microglia. The number of stained macrophages or microglia was counted in every area at a higher magnification (magnification, x400). The average of the three highest values was used as the final value (23 (link),24 (link)).
The samples were examined using a Nanozoomer Digital Pathology (NDP; Hamamatsu Photonics; magnification, x100), which was used to identify five regions (hot spots) with the highest density of stained CD68+ macrophages or microglia. The number of stained macrophages or microglia was counted in every area at a higher magnification (magnification, x400). The average of the three highest values was used as the final value (23 (link),24 (link)).