Mesenchymal stem cells (MSC), multipotent stem cells of a grown human body are used more and more in clinical investigations. Their differentiation potential enables their application in traumatology, cardiology, neurology. However, more and more investigators consider therapeutic effectiveness of MSC transplantation proved by many preclinical and clinical studies to be due to not only differentiation but also a regulatory function of these cells. Application of MSC in immunopathologic conditions provides the opportunity to clarify their regulatory characteristics, ability to influence immune process within the body. Nowadays, there is a lot of experience of MSC usage in both different experimental models and in clinic. The present data analysis allows to discuss the influence of mesenchymal stem cells on separate parts of an immune system of the vertebrate.

The article presents results of investigation into comparative evaluation of the effects of autologous intramyocardial transplantation of multipotent mesenchymal stromal cells taken from bone marrow and of mononuclear bone marrow fraction upon perfusion of a rabbit ischemic myocardium. Myocardial infarction was simulated by means of ligation of the left coronary artery descending branch. Myocardium perfusion was evaluated with single-photon emission computed tomography with the application of a radiopharmaceutic drug [RPD] ^99mTc-tetraphosmine [Myoview] prior to the simulation of myocardial infarction and in 10 days, 1.5 months, 3,6 and 12 months. The animals were divided into three groups: the 1^st group [n=12] included animals whom multipotent mesenchymal bone marrow stromal cells were introduced into the ischemic zone [2Ч10⁶]; in the 2^nd group [n=14] mononuclear bone marrow fraction was introduced [2Ч10⁶]; and the 3^rd group [n=15, control] where growth medium was used.

In all the animals of the1^st and 2^nd groups, considerable improvement of perfusion was observed in 1.5 months following the operation. Mean values of the RPD accumulation were 0.92±0.03 and 0.89±0.031 respectively. In the control group this value was 0.62±0.02. By the third month following the operation complete normalizing of perfusion occurred in the experimental groups with the RPD accumulation level of 1.00±0.02 and 0.98±0.01, whereas this parameter did not increase in the control group and was 0.61±0.01. On the 10^th day after the operation the perfusion evenness parameters in pathologic and reference zones were as follows: in the 1^st group - 2.7±0.2 and 2.1±0.2; in the 2^nd group - 2.6±0.2 and 1.8±0.3; in the controls - 2.8±0.3 and 2.1±0.1. In 3 months after the infarction simulation these values did not significantly differ in the 1^st and 2^nd groups [1.9±0.2; 2.0±0.1 and 2.1±0.1; 2.0±0.2]; in the controls the unevenness of perfusion increased considerably and amounted up to 3.5±0.2 in the damaged segment as compared with 2.0±0.1 in the intact one.

Physiologic and reparative regeneration of bone tissue after transfusion of bone marrow GFP-positive mononuclear cells of mice C57B1 /6-TgN(ACTbGFP)1 Osb was studied in C57B1/6 mice exposed to radiation. It is shown that transplanted cells are able to differentiate into osteoblasts and osteocytes in both physiologic and reparative osteogenesis, these cells having priority to proliferation and differentiation in the recipient exposed to radiation. The GFP-positive osteocytes number within the substance reached 31±8%.

The article presents the analysis of properties of a new material for implant production - porous titanium. It is demonstrated that the material possesses adequate mechanical characteristics. The absorption ofbiologic fluid was 7.5%. The material is compatible to living cells. While mouse bone marrow cells and fetal human hepatocytes were being cultured under Dextor system conditions and in vivo in mice such an implant functioned as a source of hemopoesis within the whole period of observation - up to 9 months. The data on depressing influence on growth and development of lymphomas were obtained. Thus, the material given can be considered as a perspective carrier for cells in transplantation and artificial organ creation.

The modern findings on gene expression interchanging that characterize manifestation of epithelial and mesodermal (mesenchymal) cells within early embryogenesis are presented. Based on our data obtained while using immunocytochemisrty method (CD43, CD45, CD14, CD44, CD54, CD56, CD90, CD105 antibodies) the authors consider the part of mesenchymal stem cells to be epithelial ones. It is suggested that interchanging of epithelial and mesenchymal phenotype features are general biologic natural phenomenon in ontogenesis.

Standard treatment modalities of patients with chronic gout using xanthine oxidase inhibitors (allopurinol) and prostaglandin inhibitors (nonsteroid antiinflammatory drugs) lose their efficacy gradually. The given clinical observation demonstrates positive treatment results after having used autologous cells of bone marrow in a patient with gout.