Changes in Macrophage Subpopulations in Rat Liver at Different Stages of Experimental Fibrosis

The number, phenotypic composition, and functional properties of macrophages in the liver of Wistar rats change depending on the stages of fibrosis induced by thioacetamide. In the sinusoidal capillaries of the liver of control rats, CD68⁺ wing-shaped cells were mainly detected. The number of CD68⁺ cells at the stages of fibrosis before the process of its transformation into cirrhosis was 2-fold higher (p=0.0000) than in the control. At later terms of the experiment, no significant differences were found. Immunohistochemical method revealed two morphologically different groups of CD68⁺ cells differing in shape and localization. At all stages of the experiment, round and elongated CD206⁺ cells of were detected in the sinusoidal capillaries. At the stage of cirrhosis (13 weeks), the number of CD206⁺ cells was higher than during the third week of the experiment by 3.21 times (p=0.0000). Later, a decrease in the number of CD206⁺ cells was observed. At the same time, in the portal zones and connective tissue septa around the false hepatic lobules, round CX3CR1⁺ cells were noted. By the end of the experiment (17 weeks), their number exceeded that on the third week of the experiment by 5.66 times (p=0.0000).