Phenotypic profile of peripheral blood lymphocytes in patients with inflammatory bowel diseases

Mechanisms of recognition and effector responses of immune system upon initiation and maintenance of immune-mediated inflammation and tissue damage in inflammatory bowel diseases, including Crohn’s disease and ulcerative colitis (UC), have been actively studied over recent time. Existing evidence suggests these diseases to be caused by abnormal immune response against intestinal flora microorganisms in genetically susceptible individuals. Despite available data on the features of immune disorders in ulcerative colitis and Crohn’s disease, there are still many questions about the involved minor lymphocyte subpopulations and contribution of various functionally active molecules, which play a key role in recognition and initiation of the immune response and can be considered biomarkers of a pathological process in inflammatory bowel diseases. The populations of T lymphocytes with γδT cell receptor, B1 cells and NK T lymphocytes are of greatest interest, as well as functionally active TLRs (Toll-like receptors), CD89, CD314, etc. Due to substantial progress in studying the nature of recognition and activation of the immune cells, the paper presents phenotypic and functional characteristics of major and minor subpopulations of peripheral blood lymphocytes observed in 25 patients treated at the Surgery Department of the State Institution “Minsk Regional Clinical Hospital” (Republic of Belarus) from 2018 to 2020. The detected changes in peripheral blood lymphocyte phenotype of inflammatory bowel diseases patients suggest distinct immunological profiles prevailing in the damage mechanisms in Crohn’s disease and ulcerative colitis. I.e., in Crohn’s disease patients, B1 lymphocytes with CD19+CD5+ and NK cells in combination with increased CD56bright population, as well as NK T cells with anti-inflammatory and regulatory activity are involved into genesis of the disease. In ulcerative colitis, T, B, NK lymphocytes with pro-inflammatory phenotype and T lymphocytes with γδ T cell receptor may play a pathogenetic role in maintenance of chronic inflammation. With respect to functional significance of activating receptors, the number of TLR4- и CD89-positive cells may be used for developing immunological criteria/ biomarkers of therapeutic efficacy of new drugs. Studying interactions between innate and adaptive immunity will open new perspectives in understanding immunological disorders associated with chronic gastrointestinal inflammation

Phenotype characteristic of colonic intraepithelial lymphocytes in patients with Crohn's disease

Intraepithelial lymphocytes (IEL) play a critical role in maintaining the immune balance of the gut and provide the first line of mucosal defense against luminal antigens as well as rapidly respond to epithelial injury. Recently, IEL have received a lot of attention as key mediators of aberrant immune response resulted in persistent immune activation, inflammation and altered intestinal barrier function, seen in Crohn's disease (CD). This study describes for the first time subsets of colonic IEL in CD patients as compared to healthy controls aimed at characterization of altered IEL contribution to the pathogenesis of Crohn's disease.The peripheral venous blood and colon tissues were obtained from 10 CD patients and 6 donors. IEL were isolated from the mucosa by incubation the tissue in a predigesting solution. Lymphoid cells phenotype was investigated using monoclonal antibodies and flow cytometry.The majority of colonic IEL was identified as СD3+T lymphocytes and no significant differences were found in their numbers in investigated groups. However, changes in T cell subsets composition have been shown: the ratio of СD3+СD4+IEL and СD3+СD8+IEL was 1:1 in colon of CD patients and correlated with T cells in peripheral blood (R = 0.7; p < 0.05) while donor tissues were characterized by expected СD3+СD8+T killers prevalence and the ratio reached 1:2 (p < 0.05). The increase of unconventional γδIEL (mainly due to V81+T cells) and СD161+T cells in association with TNK cells decrease were revealed in colon (p < 0.01) as well as in peripheral blood (p < 0.05) of CD patients as compared to donors. Moreover, the number of colonic γδIEL was correlated with disease location (R = -0.6; p < 0.05), and disease behavior (R = 0.7; p < 0.01) according to Montreal classification.The observed data indicates changes in colonic IEL composition in CD patients that may provide valuable insight into the contribution of T helpers, γδT cells and mucosa-associated СD161+T cells in autoimmune intestinal inflammation but need further possible mechanisms discussion

Получение цельноорганного скаффолда печени крысы

Engineering a three-dimensional scaffold opens up great prospects for creation of manufacturing biological artificial organs. The article presents a method of perfusion decellularization of a rat liver, with the main problems and options for their solution being analyzed. Perfusion of a donor liver with 0.1 % a sodium dodecyl sulfate (SDS) solution allows obtaining a high-quality cell-free matrix characterized by preserved hepatic architectonics, patent vascular bed, residual DNA of less than 1 %, no signs of collagen fibers destruction and tissue edema. The obtained scaffold can be used for recellularization by allogeneic cell cultures when creating volumetric tissue-engineered designs.Получение трехмерного скаффолда открывает широкие перспективы для инженерии биоискусственных органов. В работе представлен метод перфузионной децеллюляризации печени крысы с анализом основных проблем и вариантов их решения. Перфузия донорской печени 0,1 %-ным раствором додецилсульфата натрия (SDS) позволяет получить качественный бесклеточный матрикс, характеризующийся сохранностью печеночной архитектоники, проходимостью сосудистого русла, остаточной ДНК менее 1 %, отсутствием признаков деструкции коллагеновых волокон и тканевого отека. Полученный предложенным методом скаффолд может использоваться для рецеллюляризации аллогенными клеточными культурами при создании объемных тканеинженерных конструкций

MESENCHYMAL STEM CELLS AS A THERAPEUTIC STRATEGY FOR MULTIPLE SCLEROSIS: ISSUES AND PERSPECTIVES

The ability of mesenchymal stem cells (MSC) to influence the regulatory/suppressive effect in the autoimmune process and promote remyelination allows to consider them a new method of multiple sclerosis (MS) therapy, by means of modifying the disease activity. Genetic stability, proliferative potential, ability to migrate into the damaged tissue areas and agreed protocols for isolation and culture are the main advantages for successful autologous, as well as allogeneic MSC therapy. Preliminary results from clinical studies using MSC application in MS patients show efficiency and safety of this therapeutic approach. Nevertheless, successful demonstration of the cell therapy in MS is only possible after detailed analysis and understanding of MSC biology and mechanisms of appropriate intercellular interactions. The article reviews general experience in usage of immunomodulatory and neuroprotective properties of MSС in MS, and highlights the issues of validity in cell-based therapy taking into account both in vitro и in vivo studies

γδТ-LYMPHOCYTES: GENERAL CHARACTERISTICS, SUBPOPULATION PROFILE, BIOLOGICAL ROLE, AND FUNCTIONAL FEATURES

Abstract. γδТ lymphocytes represent a poorly investigated heterogeneous population of T cells that are found, predominantly, in mucosal structures, and express common characteristics of innate and acquired immunity. Lack of both antigen processing and MHC-restriction determines an ability of γδТ cells to identify broad spectrum of antigens, the origin of which is yet unknown, and the recognition mechanism have been not established yet. A variety of biological functions, first of all, cytolysis, immune regulation, antigen presentation and repair of tissue damage, define a unique role of this population in infectious diseases, tumors, and autoimmune disorders. Nowadays, principal efforts of scientists are directed to investigation of γδТ cell therapeutic potential, search and production of γδТ cell agonists, as well as design and optimization of herapeutic protocols that may be targeted to γδТ lymphocytes