[Nonadhesive populations in cultures of mesenchymal stromal cells from hematopoietic organs in mouse and rat].

The study of adhesive properties of multipotent mesenchymal stromal cells evaluated from fibroblast colony-forming units in the bone marrow of adult mice and rats in populations of cells attached and unattached to plastic substrate after 2 h to 7 days in culture demonstrated both similarities and differences. The increase in the fibroblast colony-forming units in the adhesive population peaked on day 7 of in vitro culture in both cases; however, nearly no fibroblast colony-forming units were observed in the nonadhesive population from the mouse bone marrow in this period. Conversely, the number of colonies from the rat bone marrow nonadhesive population on day 7 of culture considerably increased, and this nonadhesive population in long-term culture became the source for subsequent nonadhesive subpopulations containing fibroblast colony-forming units. After 7 days of in vitro culture, the suspension of cells isolated from the liver of 17-day-old rat fetuses also contained a fraction of unattached fibroblast colony-forming units. In the nonadhesive subpopulations from the bone marrow and fetal liver, fibroblast colony-forming units were observed up to day 48 and 30, respectively. Stromal cell precursors of nonadhesive subpopulations from the rat bone marrow featured a period of colony formation reduced to 7 days (i.e., they were formed 1.5-2 times faster compared to the primary culture). The total number of fibroblast colony-forming units from all nonadhesive subpopulations was roughly 6 and 7.4 times that of the adhesive population of the primary culture from the bone marrow and fetal liver, respectively. Considering that the mammalian bone marrow remains the preferred source of mesenchymal stromal cells, using nonadhesive subpopulations in the presented culture system can considerably increase the yield of stromal precursor cells.

Studies on clonogenic hemopoietic cells of vertebrate in space: problems and perspectives.

Hemopoietic tissues were studied in vertebrates launched aboard the Soviet (Russian) biosatellites ("Cosmos-1129, 1514, 1667, 1887 and 2044"; "Bion-10 and 11") between 1980 and 1996. In the bone marrow of rats exposed to spaceflight conditions, a statistically significant decrease in cell number was revealed in the progenitor cell compartment accounting for the compensatory response of granulocyte-macrophage (CFU-gm) and erythrocyte lineages (BFU-e and CFU-e) and in the compartment of multipotent hemopoietic stem cells (CFU-s), which is responsible for the permanent renewal of hemopoietic tissue. The number of stromal fibroblastic progenitors (CFC-f) in the bone marrow of these rats was also reduced. Apparently, changes in the hemopoietic stroma damage the hemopoietic microenvironment and, hence, may be responsible for changes observed in the hemopoietic tissue proper. Attempts were made to develop methods for analyzing morphologically indiscernible clonogenic hemopoietic cells of newts, and studies on the effects of spaceflight factors on these cells were performed. The results showed that the numbers of clonogenic cells in newts of the flight group newts were significantly lower than in control newts. The data obtained are used as the basis for formulating the problems to be studied, drawing up a program for further research on the effects of spaceflight factors on stem and other clonogenic hemopoietic cells, and developing new experimental models for analyzing stem cells, the state of the hemopoietic stroma, etc.

[The 5-fluorouracil sensitivity of the hematopoietic stroma of the bone marrow and spleen]. / Chuvstvitel'nost' k 5-ftoruratsilu krovetvornoi stromy kostnogo mozga i selezenki.

We studied the effect of a single injection of 5-fluorouracil (5-FU) (150 mg/kg) on the numbers of stromal precursor cells (CFU-F) in the bone marrow and spleen and their capacity for formation of hemopoietic foci after ectopic transplantation under the renal capsule. 5-FU decreased the number of CFU-F in the bone marrow and spleen of mice and rats to 30 - 50% of the control values. The size of transplants, as estimated according to the number of hemopoietic clonogenic (CFU-S) and nucleated cells, diminished within the first two months after transplantation. Within four months after transplantation the size of the bone marrow transplants approached the control level, while that of the spleen transplants markedly exceeded the control level. Differences in the growth rate of regenerating transplants of the hemopoietic organs are discussed with special reference to the organ specific features of populations of the stromal cells.

[Hemopoiesis on stromal sublayers formed by constant lines of fibroblasts]. / Krovetvorenie na stromal'nykh podsloiakh, obrazovannykh postoiannymi liniiami fibroblastov.

We studied the formation of hemopoietic colonies on an artificial sublayer in the peritoneal cavity of mice under the influence of stromal sublayers consisting of fibroblasts of six constant cell limes. All studied lines of stromal cells supported the formation of granulocytic foci and some of them supported the formation of erythroid foci as well. It was shown that hemopoiesis was preserved or, in some cases, enhanced on sublayers of fixed (metabolically inactive) cells. The treatment of fibroblasts by E. coli lipopolysaccharide did not lead, as a rule, to significant stimulation of hemopoiesis.

[Effect of continuous gamma-radiation at low doses on clonogenic hemopoietic (CFU-S) and stromal (CFU-F) bone marrow cells ]. / Effekt nepreryvnogo gamma-oblucheniia v nizkikh dozakh na klonogennye krovetvornye (KOE-S) i stromal'nye (KOE-F) kletki kostnogo mozga.

We studied the effects of low doses of continuous gamma-irradiation (Co60, 10 days, mean daily dose power 1.5-2.0 mGy, total dose 15 mGy) on hemopoietic and stromal progenitor cells of murine bone marrow. The content of hemopoietic clonogenic cells representing a "younger" (CFU-S-11) and more "mature" (CFU-S-7) categories in the compartment of stem cells was determined in the bone marrow. The state of bone marrow stroma was estimated by the method of in vitro cloning according to the number of progenitor cells that form colonies of fibroblasts (CFU-F) and by the method of ectopic transplantation according to the capacity of stroma of organizing and building new hemopoietic territories. Continuous gamma-irradiation at low doses, that were by one order of magnitude lower than those inducing hermesis, exerted a stimulating effect on both hemopoietic (CFU-S) and stromal (CFU-F) progenitor cells. The number of CFU-S in the compartment of stem cells of the bone marrow markedly increased and they formed larger hemopoietic territories but these cells appeared to create a qualitatively different microenvironment, which stimulated the proliferation of CFU-S.

[Use of leukocytic serum in treatment of shin trophic ulcers with protracted healing]. / Primenenie lekotsitarnoi syvorotki v lechenii dlitel'no ne zazhivaiushikh troficheskikh iazv goleni]

The results of treatment of 85 patients with trophic ulcers of various origin by leukocytic serum were compared with the results of treatment of 46 patients treated by routine method. The best clinical and aesthetic effect of this treatment was revealed in a group of patients with trophic ulcers due to vein varicosity. From 58 patients epithelization was detected in 49 (84,5%). The relapses of trophic ulcers in a period from 6 months to 1,5 years were revealed in 5 patients. The use of leukocytic serum ensures high percent of closure of the ulcers chiefly of venous etiology.

[Effect of a leukocytic serum preparation on hematopoietic cells in vitro]. / Vliianie preparata leikotsitarnoi syvorotki na krovetvornye kletki in vitro.

The effects of leucocyte serum (LS) on bone marrow cells (BMC), thymus and HL-60 human myeloid leukemia cells were studied in liquid suspension and agar cultures. LS increased 3H-thymidine incorporation in BMC and intensified the cloning efficiency of granulocyte-macrophage progenitor cells (CFU-GM) and human myeloid leukemia cells. No significant stimulatory effect on thymus cells was observed. It has been shown that LS prevents or markedly decreases the effect of granulocyte inhibitor (GI-3S2).

[Effect of various pharmacologic preparations on the viability of Chinese hamster fibroblasts in vitro]. / Vliianie nekotorykh farmakologicheskikh preparatov na vyzhivaemost' fibroblastov kitaiskogo khomiachka in vitro.

The effect of the physiologically active substances (histamine, serotonin) and their antagonists (bicarfene, cyproheptadine and preparation 407) on the growth of Chinese hamster fibroblasts in vitro has been studied. The cell survival evaluated from the number of colonies grown by the 7th day of cultivation served as criterion for the action of the substances under study. Determination of amines in fibroblast extracts was made by spectrofluorometry. It has been discovered that Chinese hamster fibroblasts are susceptible to a number of pharmacological preparations, antagonists of serotonin and histamine, and that histamine abolishes the inhibitory action of the respective antagonist on the colony growth. Biochemical analysis has shown that these fibroblasts contain tryptamine and serotonin and, tentatively, histamine. It is assumed that these endogenous physiologically active substances participate in the fibroblast growth control.