Immunohistochemical Characteristics of the Wall of Coronary Arteries in Experimental Atherosclerosis

Atherosclerosis is a chronic progressive disease of the arteries of the elastic and muscular-elastic type, which includes the features of the inflammatory process and lipid metabolism disorders. One of the major cells taking part in the development of the atherosclerotic process are dendritic cells, the main function of which is the recognition and presentation of antigens to T-lymphocytes. There are several subpopulations of dendritic cells, depending on the degree of maturity. The purpose of the study was to establish the morphological features of dendritic cells of the coronary arteries wall at different stages of the experimental atherosclerosis. Material and methods. The research was conducted at 120 nonlinear rats of both sexes weighing 180-210 g on average. Animals were divided into 2 groups: I - control group (n = 40), who were administered by 0.1 ml of Freund's incomplete adjuvant intracutaneously, and II - the experimental group (n = 80), that were immunized human native low density lipoproteins (ProSpec, USA) at a dose of 200 μg intracutaneously with addition of 0.1 ml of Freund's incomplete adjuvant (Becton Dickinson, USA). Dendritic cells were detected by using polyclonal antibodies S-100 and monoclonal antibodies CD1α. A semiquantitative scale from 0 to 3 points was used to determine the intensity of expression of immunohistochemical markers. Histological examination of coronary arteries wall was perfomed by hemothoxylin and eosin. Results and discussion. It was found out that the dendritic cells of types 1 and 2 were identified in the wall of intact coronary arteries, while dendritic cells of types 3 and 4 were detected in the wall of coronary arteries with atherosclerotic damages. The number of dendritic cells in the wall of the coronary arteries of the medium caliber was greater than in the coronary arteries of small caliber. For the first time, the appearance of dendritic cells of type 3 was observed on the 12th week of the experiment, which corresponded to the stage of lipoidosis. The appearance of dendritic cells of type 4occurred on the 18th week of the experiment and associated with the stage of liposclerosis. Conclusion. Dendritic cells changed their own morphological structure, topography and levels of expression of immunohistochemical markers S-100 and CD1α at different stages of the atherosclerotic process. The quantitative dynamics of the dendritic cells during the experiment was linear, increasing from 3.89±0.07 cells in the 4th week to 14.72±0.31 cells in the 18th week.