Background: According to the World Health Organization, more than 250 million people worldwide are chronically infected with the hepatitis B virus, and almost 800.000 patients die annually of mediated liver disorders. Therefore, adequate biological test systems are needed that could fully simulate the course of chronic hepatitis B virus infection, including in patients with hepatocellular carcinoma. Methods: In this study, we will assess the effectiveness of existing protocols for isolation and cultivation of primary cells derived from patients with hepatocellular carcinoma in terms of the yield of viable cells and their ability to replicate the hepatitis B virus using isolation and cultivation methods for adhesive primary cells, flow cytometry and quantitative polymerase chain reaction. Another part of our study will be devoted to evaluating the effectiveness of hepatocellular carcinoma grafting methods to obtain patient-derived heterotopic and orthotopic xenograft mouse avatars using animal X-ray irradiation and surgery procedures and in vivo fluorescent signals visualization and measurements. Our study will be completed by histological methods. Discussion: This will be the first extensive comparative study of the main modern methods and protocols for isolation and cultivation primary hepatocellular carcinoma cells and tumor engraftment to the mice. All protocols will be optimized and characterized using the: (1) efficiency of the method for isolation cells from removed hepatocellular carcinoma in terms of their quantity and viability; (2) efficiency of the primary cell cultivation protocol in terms of the rate of monolayer formation and hepatitis B virus replication; (3) efficiency of the grafting method in terms of the growth rate and the possibility of hepatitis B virus persistence and replication in mice. The most effective methods will be recommended for use in translational biomedical research.

Since the beginning of the 21th century, major outbreaks of human respiratory syndromes caused by coronavirus infections have caused more than million deaths on the planet. Despite the fact that the first wave of the coronavirus infection took place back in 2002, even now there is not any adequate animal model that would meet the needs of the scientific community for reproducing the pathogenesis, clinical manifestations, immunogenicity, development and testing of preventive and therapeutic compounds specific to Severe Acute Respiratory Syndrome, Middle East Respiratory Syndrome, and Coronavirus Disease 2019 (COVID-19).The purpose of the study is to provide relevant information on known animal models of human respiratory syndromes caused by coronavirus infections and to focus the reader's attention on their adequacy, which consists in the most accurate imitation of clinical signs and pathomorphological changes.

The main challenge after engraftment of human tissues to mice is the development of graft-versus-host disease. It often occurs in an acute form, which reduces the time frame for observations. This is especially important to take into account when planning long-term studies of chronic diseases such as HIV infection. In addition, in mice, even with a similar genotype but different origin, the interaction between the graft and the recipient’s organism can manifest itself differently. We engrafted human immune cells in three different concentrations into immunodeficient NOD/Shi-Prkdc^scid Il2rg^em1/Cyagen mice. Then, the initial points of development of a severe graft-versus-host reaction and the maximum possible time window for humane observation were determined. The study included regular complete blood count and the monitoring of the dynamics of the concentration of human cells in the blood of mice. In addition, the effect of grafts on the activation of the recipient’s immune system was assessed. Finally, necropsy and histological and immunohistochemical examinations of the organs were performed to determine the localization of human cells. In this way, critical factors determining the success of human immune system reconstitution in mice were identified.

The book «Genetic Technologies» covers a wide range of topics in the field of genetic technologies related to genome editing, and summarizes the latest scientific data on the use of programmable nucleases in various fields related to genome modification. The monography «Genetic Technologies» will be interesting and useful for students of biological and medical universities, graduate students, young scientists, researchers, healthcare professionals and will help them to systematize knowledge in the rapidly developing field of genetic technologies and genome editing. It is believed that the innovative technologies described in the book will serve as a scientific basis for the development of diagnostic and therapeutic agents to fight against currently incurable diseases. The book «Genetic Technologies» was published with the support of the Ministry of Science and Higher Education of the Russian Federation within the framework of a grant in the form of a subsidy for the creation and development of the «World Сlass Genomic Research Center for Ensuring Biological Safety and Technological Independence under the Federal Scientific and Technical Program for the Development of Genetic Technologies», agreement No. 075-15-2019-1666. Книга «Генетические технологии» издана при поддержке Министерства науки и высшего образования РФ в рамках гранта в форме субсидии на создание и развитие «Центра геномных исследований мирового уровня по обеспечению биологической безопасности и технологической независимости в рамках Федеральной научно-технической программы развития генетических технологий», соглашение № 075-15-2019-1666.

Understanding the entire pathogenesis of HIV infection, from penetration at the gates of infection to the induction of severe immunodeficiency, is an essential tool for the development of new treatment methods. Less than 40 years of research into the mechanisms of HIV infection that lead to the development of acquired immunodeficiency syndrome have accumulated a huge amount of information, but HIV's own unique variability identifies new whitespaces. Despite the constant improvement of the protocols of antiretroviral therapy and the success of its use, it has not yet been possible to stop the spread of HIV infection. The development of new protocols and the testing of new groups of antiretroviral drugs is possible, first of all, due to the improvement of animal models of the HIV infection pathogenesis. Their relevance, undoubtedly increases, but still depends on specific research tasks, since none of the in vivo models can comprehensively simulate the mechanism of the infection pathology in humans which leads to multi-organ damage. The aim of the review was to provide up-to-date information on known animal models of HIV infection, focusing on the method of their infection and anatomical, physiological and pathological features.

This will be the first extensive comparative study of the main modern methods and protocols for isolation and cultivation primary hepatocellular carcinoma cells and tumor engraftment to the mice. All protocols will be optimized and characterized using the: (1) efficiency of the method for isolation cells from removed hepatocellular carcinoma in terms of their quantity and viability; (2) efficiency of the primary cell cultivation protocol in terms of the rate of monolayer formation and hepatitis B virus replication; (3) efficiency of the grafting method in terms of the growth rate and the possibility of hepatitis B virus persistence and replication in mice.The most effective methods will be recommended for use in translational biomedical research.