Comparative Study of Pathomorphological Changes in Animal Lung Tissue when Modeling Infection Caused by the SARS-CoV-2 Virus

Abstract

The aim of the work was to study the features of the infectious process in the lungs of animals used as models for assessing SARS-CoV-2 pathogenicity.Materials and methods. The strain of SARS-CoV-2 alpha variant virus was used in the work. The experiments were carried out on linear and transgenic mice, Syrian hamsters, guinea pigs, ferrets and two types of primates: rhesus macaques and green monkey. The pathomorphological examination was performed by optical microscopy of histological lung preparations using a computerized microscope with digital microphotography.Results and discussion. A comparative histological analysis of the lungs in six different types of laboratory animals was carried out when modeling a new coronavirus infection; similar morphometric signs of the severity of the disease caused by the SARS-CoV-2 virus in sensitive animals were determined, and a dose-dependent correlation of pathological changes in lung tissues with intranasal administration of various infectious doses was revealed. The features of pathomorphological changes in six different animal species in the simulation of a new coronavirus infection have been characterized, and their dose-dependent nature determined. The presented research results can be used to select a model animal for the purpose of in-depth study of the pathogenesis of COVID-19 caused by newly isolated coronavirus variants, the dynamics of immune reactions of the body during the development of the disease, as well as in vivo studies of the protective effect of promising therapeutic drugs and vaccines.