P0454MORPHODENSITOMETRIC FEATURES OF PERIPHERAL BLOOD LYMPHOCYTES IN PATIENTS WITH PRIMARY GLOMERULONEPHRITIS
Authors: Kaminskyi Vitalii 
Published: June 2020

Abstract

Background and Aims
Lymphocytes play an important role in the development of glomerulonephritis (GN). Their subpopulations are activated under the influence of certain cytokines that act on the activation factors of transcription of these cells, leading to the corresponding regulation of gene expression. However, in addition, in the regulatory processes of lymphocyte functions, epigenetic modifications of the degree of nuclear chromatin compaction are important. The morphological manifestation of the latter may be the state of the optical density of the nuclei and the range of its variability due to the ratio of chromatin condensation/decondensation. The study of the features of potentially reversible changes in chromatin structure in somatic cells becomes actual. One of the convenient objects for studying the epigenetic mechanisms of the genome functioning regulation are interphase nuclei of peripheral blood lymphocytes. Morphodensitometric study permits to establish compensatory changes at the cellular level and to evaluate the functional state of the hereditary apparatus. The aim of the research was to study the morphodensitometric features of genome status of peripheral blood lymphocytes in patients with primary GN.

Method
We examined 119 patients (76 men and 43 women) with primary GN. The average age of patients was (39.65±14.16) years. The patients underwent a renal biopsy to verify the morphological form of the disease. For comparison, a survey of 30 healthy individuals was conducted. Chromatin of nuclei and its changes were studied using an image analyzer based on the programm Image Tool for Windows (v. 3.0). The advantage of this method is the possibility of a combined assessment of morphometric (area, perimeter), spectrometric (optical and integral density) data with the analysis of the microanatomy of isolated chromatin blocks and the chromatin function at the same time. The study of the morphodensitometric characteristics of peripheral blood lymphocytes is an informative and accessible method for assessing the general state of the function and structure of the hereditary apparatus of the organism.

Results
The sexual characteristics of the morphometric and optical parameters of lymphocytes nuclei of patients were established. So, in all patients and especially women, a decrease in the perimeter of lymphocytes nuclei was registered in 1.25 and 1.31 times, respectively (p &lt;0.05). The area of these cells nuclei also naturally decreased in 1.22 times in all patients (in 1.08 and 1.34 times in men and women, respectively) compared to the control (p&lt;0.05). A significant decrease in the area of lymphocytes nuclei with an unchanged density of chromatin packing in these nuclei limits the space inside the nucleus for the interaction of individual chromosome loci in this space. Such limitations can be a serious obstacle to the normal functioning of the genome and its repairing processes. Meanwhile, differences in the optical density parameter of lymphocytes nuclei in both groups were defined. The minimum and maximum optical density were higher in the group of patients, and the range of optical density variability showed wider borders of functional heterogeneity of cells compared to the control.

Conclusion
Comparative analysis of morphodensitometric features of peripheral blood lymphocytes in patients with primary GN detected the changes in the ratio of chromatin condensation/decondensation and normal structure of nuclei, that may indicate functional disorders of the genotype due to exo- and endogenous factors.