No abstract

To investigate the effect of pre-transplantation of multipotent stromal cells (MSCs) of bone marrow on gastric ulcer formation and the state of the immune system in conditions of acute and prolonged stress. Wistar rats reproduced immobilizing water-immersion stress of 2 types: acute and prolonged. Investigated the number and area of stress ulcers, thymus and spleen, as well as hematologic parameters, proliferative and cytotoxic activity of peripheral blood mononuclear cells, splenocytes and cells of lymph nodes, determined the absorption activity of neutrophils. With prolonged stress as a result of MSC transplantation, the number and area of ulcers significantly decreased, indicating the adaptive protective effect of cells. With acute stress, the introduction of MSC had virtually no effect on ulcer formation. With prolonged stress, there was a decrease in thymus, spleen and leukocyte counts in the blood. Under the influence of transplanted MSCs, the number of all mobilized cells was normalized with the exception of lymphocytes. The natural cytotoxicity and proliferative activity of splenocytes, cells of lymph nodes and peripheral blood in acute and prolonged stress as a result of the introduction of MSC did not change significantly. The introduction of bone marrow MSС 24 h before the last reproduction of stress responses in the model of prolonged stress significantly reduced the number and area of ulcers, which generally indicates the anti-ulcer effect of cells, and normalized the stress-induced quantitative cellular changes in the immune system. Transplantation of bone marrow MSCs to rats prior to reproduction of stress enhances the adaptive antistress mechanisms that develop during prolonged stress, leading to suppression of gastric ulcer formation and significantly altering immune system activity. It can be assumed that one of the mechanisms of action on the body of MSCs is to promote the formation of adaptive responses.

The paper provides a comparison of properties of cryopreserved fetal murine multipotent stromal cells (MSCs) of skin-muscular origin and those derived from adult thymus in culture in vitro. Fetal MSCs showed a 30% higher number of average population doublings within 24 hrs, and 41% lower average population doubling time. It was found that the fetal MSCs of the 4th passage had a 39% higher clonogenic activity than the adult thymus-derived ones. Fetal MSCs and those derived from adult thymus differentiated in osteogenic and adipogenic lineages with equal efficiency in special culture media. Fetal and thymus-derived MSCs were characterized by almost the same high ability of contact interaction with thymocytes, and the fibroblast-lymphocyte rosette (FLR) formation. They were far less active in FLR formation with lymph node cells. This indicated the presence of membrane affinity for immature lymphoid cells in both MSC subpopulations. The results showed the fetal MSCs to be significantly different from the adult thymus-derived MSCs by more active kinetics of growth and clonogenic potential. However, both cell subpopulations had virtually the same ability for linear differentiation and showed high activity during contact with immature lymphoid cells. Linear differentiation and the ability to interact with lymphocytes were found to be quite stable properties of MSCs, but a proliferative activity and in vitro colony formation distinguished significantly in different types of MSCs. This can be taken into account when choosing the cells for therapy, research and results assessment.