Changes in the Number of Mesenchymal Stem Cells in Bone Marrow at Different Periods after In Vivo Exposure of the Bone Marrow to Local Infrared Laser Radiation.

We determined optimal parameters of bone marrow (BM) irradiation in vivo for rapid increase in the number of mesenchymal stem cells (MSC) at the initial stages of the culturing without changing the karyotype, polyploidy, which are observed at higher passages. Such an increase is necessary to achieve the required number of cells at the initial passages for subsequent transplantation into the body. It was shown that after irradiation with λ=0.

Effect of alpha-fetoprotein on the count of bone marrow and splenic stromal precursor cells and proliferation of their cultural descendants.

The efficiency of cloning of stromal precursor cell increased more than 2-fold in splenic cultures and more than 3-fold in bone marrow cultures 24 h after injection of Profetal preparation to mice in vivo. The number of nucleated cells did not change in the bone marrow and slightly increased in the spleen. Addition of Profetal in vitro 2-fold decreased the efficiency of stromal precursor cells colony formation in mouse splenic cultures and dose-dependently decreased this process in bone marrow cultures derived from these animals, the maximum (5-fold) inhibitory effect was observed in a dose of 50 microg/ml.

[Population dynamics of clonogenic stromal precursor cells in hemopoietic and lymphoid organs during bone marrow regeneration].

This paper describes our study on the regeneration of hemopoietic and stromal components of bone marrow after mechanically emptying the medullar cavity of the guinea pig tibia. The intensity of hemopoiesis was determined from the number of hemopoietic cells, while the concentration and total number of stromal precursor cells were used to estimate the ability of the bone marrow to produce stromal structures, including its ability to restore a specific microenvironment. We found that there was no direct correlation between the recovery characteristics of hemopoietic and stromal cells.

[Proliferative and differentiation potential of individual clones derived from bone marrow stromal precursor cells].

We present the results of a study on the proliferative and differentiation potential of individual clones of stromal fibroblasts growing in monolayer cultures of bone marrow cells. Each precursor cell yielding a large colony in primary culture is capable of up to 34 doublings in vitro. The transplantation of clones or monoclonal strains of stromal fibroblasts into the open system results in the formation of microenvironment consisting of the bone and reticular tissue and is suitable for the differentiation of all three lines of hemopoiesis.

Influence of Hyperimmunization on Formation of Plaque Forming Cells in Lymphoid Organs Made with Transplantation of Spleen Stromal Fibroblasts.

When heterotopically transplanted under the renal capsule, the strains of stromal fibroblasts from spleen cultures formed the lymphoid organs, which had no specialized structures, such as red and white pulp and consisted of the accumulations like lymphoid follicles. The purpose of the given work was the study of ability of spleen stromal fibroblast strains, when heterotopically transplanted into the organism, to transfer the specific lymphoid microenvironment. The heterotopic transplantation of spleen fragments and stromal cells, grown in vitro, was made in autologous variant.

[Bone tissue formation in organ cultures of human bone marrow].

Bone formation in adult human bone marrow organ cultures is described. When culturing marrow fragments, thick bone lamina is formed. It has well-mineralized trabecular bone matrix with bone cells incorporated and is lined with osteoblast-like cells.

[Dynamics of the mineralization of the ground substance in newly formed bony tissue in organ cultures of mouse bone marrow].

Na-beta-glycerophosphate was added to the organ culture medium of mice marrow fragments. New bone ground substance is formed, its mineralization degree and morphology being highly dependent upon glycerophosphate addition and removal periods. Complete or partial ground substance mineralization occurs, in last case calcium insoluble salts may be found in young apical or in old basal parts only.

[Formation of bone tissue by mouse bone marrow cell suspensions in organ culture].

Adult mouse bone marrow cell suspensions prepared by trypsinization were cultivated in gelatin sponges on millipore filters. When HAWP filters were used, multilayer bone structure was formed. It contained mineralized ground substance, incorporated bone cells and osteoblast layer.

[Bone formation in bone marrow organ cultures].

Bone tissue composed of typical bone trabeculae containing ground substance with incorporated osteogenic cells and osteoblast layer was formed in organ cultures of bone marrow obtained from adult mice. Electron microscopic properties of the bone formed in vitro were identical to those of the bone tissue in vivo. The mineralization of the bone took place only in the presence of Na-beta-glycerophosphate in the culture medium.

[Growth of myeloid plaques on layers of cultured stromal fibroblasts].

The cells of syngeneic bone marrow were added in the primary monolayer cultures of bone marrow, thymus and peritoneal fluid of the mouse. Discrete plaques with several dozens to several thousands of myeloid cells developed on the surface of fibroblast colonies within 2--7 days. It was shown that both the size and rate of formation of myeloid plaques were markedly higher in the culture of thymus fibroblasts than in those of bone marrow and peritoneal fluid fibroblasts.

[Interaction of myeloid cells with stromal fibroblasts in monolayer cultures].

Stromal fibroblasts of bone marrow, spleen and thymus origin as well as fibroblasts of peritoneal fluid origin are shown to have no difference in the ability to bind morphologically distinguishable granuloid cells in monolayer cultures. On the contrary, thymus fibroblast colonies encourage the development of myeloid cell plaques (which are formed by bone marrow hemopoietic precursor cells) a great deal stronger than do bone marrow and peritoneal fluid fibroblast colonies. It means that their different origin may be revealed when they interact with hemopoietic precursor cells but not with differentiated myeloid cells.

[Formation of foci of myeloid cells on colonies of thymus and bone marrow fibroblasts in monolayer cultures].

A culture system favouring myeloid cell formation directly on the surface of mouse stromal fibroblast colonies has been developed. It has been shown that the plaques formed are both much more numerous and essentially larger on stromal fibroblast colonies of thymus than of bone marrow origin. Consequently, hemopoietic precursor cells that form the myeloid plaques in the monolayer cultures interact dissimilarly with stromal mechanocytes of different origin.

[Hematopoietic and lymphoid cell adhesion to stromal mechanocytes in vitro].

In vitro adhesion of guinea pig bone marrow and spleen cells to cultured fibroblasts of bone marrow, spleen, thymus and peritoneal fluid origin was studied. Much better binding of myeloid cells to fibroblasts than to macrophages was observed, but no difference in adhesion to stromal fibroblasts of different origin was focund. The number of adhereing cells per one stromal mechanocyte depends on the number of adhesion sites on the surface of target cells.