In Vivo Effects of Human Bone Marrow Mesenchymal Stromal Cells on the Development of Experimental B16 Melanoma in Mice.

Experiments on F1(CBA×C57BL/6) mice with experimental metastatic melanoma B16 F10 showed that single intravenous injection of xenogeneic bone marrow mesenchymal stromal cells (BM-MSC) in a dose of 106 cells/mouse significantly increased 100-day survival rate of tumor-bearing animals. In contrast, administration of BM-MSC in a dose of 2×106 cells/ mouse reduced survival rates in comparison with the biocontrol (injection of B16 cells alone, 5×105 cells/mouse). This phenomenon can be related to in vivo participation of BM-MSC in reprogramming of resident tissue macrophages, including tumor microenvironment, towards pro- (M1) or anti-inflammatory (M2) phenotype. This is indirectly confirmed by the data on switching from activation to inhibition of ROS-producing activity of blood mononuclears and peritoneal macrophages in tumor-bearing mice in the test of luminol-dependent zymosaninduced chemiluminescence.

Syngeneic and Xenogeneic Transplantations of Mesenchymal Stromal Cells Modify the Production of Reactive Oxygen Species by Blood Mononuclears of Mice.

In vivo modifying effects of bone marrow mesenchymal stromal cells of humans and laboratory mice on ROS production by mouse blood mononuclears are studied by luminol-dependent zymosan-induced chemiluminescence after syngeneic and xenogeneic transplantation into systemic blood flow. The chemiluminescent activity of mouse blood mononuclears has increased early (1 day) after syngeneic (mouse mesenchymal stromal cells) and xenogeneic (human mesenchymal stromal cells) transplantation. Later, 7-21 days after syngeneic and xenogeneic transplantation, the chemiluminescent activity of mouse mononuclears is suppressed. The probable mechanisms of involvement of the transplanted mesenchymal stromal cells in reprogramming of the blood mononuclear phagocytes from proinflammatory (M1) to anti-inflammatory (M2) phenotype under conditions of their in vivo interactions are discussed; a frequent manifestation of this reprogramming is transition of the phase of activation into inhibition of ROS-producing activity of macrophages.

Modifying Effect of Autotransfusion of Mesenchymal Stromal Cells on the Production of Reactive Oxygen Species and Cytokines by Mononuclear Cells in Patients with Chronic Heart Failure.

We studied in vivo modifying effect of autotransfusion of human bone marrow mesenchymal stromal cells on ROS generation and production of cytokines (TNFα,TNFß, IL-1α, IL-10, IFNγ, and GM-CSF) and PGE2 by mononuclear cells of patients (N=21) with chronic heart failure. These parameters were evaluated prior to (control) and after (immediately and on day 14) intravenous administration of stromal cells in doses of 100-200×106. Immediately after autotransfusion, significant increase of in vitro zymosan-induced chemiluminescence of blood mononuclear cells from 10 patients was observed. At later terms after autotransfusion (day 14), inhibition of chemiluminescent activity of blood mononuclear cells was revealed in 50% patients. We discuss possible mechanisms of involvement of transplanted autologous bone marrow mesenchymal stromal cells in reprogramming of blood mononuclear phagocytes from the pro- to anti-inflammatory phenotype under conditions of their in vivo interaction manifesting in transition from activation to inhibition of ROS-producing activity of macrophages and significant suppression of in vitro LPS-induced production of TNFα and GM-CSF by blood mononuclears against the background of significantly elevated TNFß, IL-10, and IL-1α concentrations.

[Effect of mesenchymal stem cells and entero-absorbent on cardiac function in rats following local irradiation of the chest].

Cardiac function in Wistar male rats was assessed by ECG records for 28 days following exposure of the chest to γ-rays at a dose of 6 Gy, dose rate 4 Gy/min. The exposed rats experienced a moderate cardiac ischemia and a certain increase in the load on the atria. The use of clay of Kaluga deposit and mesenchymal stem cells reduced the adverse radiation effects.

Morphofunctional study of the therapeutic efficacy of human mesenchymal and neural stem cells in rats with diffuse brain injury.

We studied the effect of transplantation of human stem cells from various tissues on reparative processes in the brain of rats with closed craniocerebral injury. Combined treatment with standard drugs and systemic administration of xenogeneic stem cells had a neuroprotective effect. The morphology of neurons rapidly returned to normal after administration of fetal neural stem cells. Fetal mesenchymal stem cells produced a prolonged effect on proliferative activity of progenitor cells in the subventricular zone of neurogenesis. Adult mesenchymal stem cells had a strong effect on recovery of the vascular bed in ischemic regions.

[Systemic transplantation of autologous mesenchymal stem cells of the bone marrow in the treatment of patients with multidrug-resistant pulmonary tuberculosis].

The study undertaken 3 years ago examined the effect of systemic transplantation of autologous mesenchymal stem cells (MSC) in the complex therapy of 27 patients with pulmonary tuberculosis, including 15 patients with multidrug-resistant pulmonary tuberculosis and 12 with extensive drug resistance of Mycobacterium tuberculosis. All the patients were bacteria-discharging persons with disseminated destructive processes in lung tissue, most (n=17) of them had chronic fibrocavernous tuberculosis. In all the patients, previous long specific antituberculous treatment was ineffective or inadequately effective. After systemic MSC transplantation, 16 patients were followed up for 1.5-2 years or more and the remaining 11 patients for at least 6 months. After MSC administration, a positive clinical effect was observed in all 27 cases; bacterial discharge stopped in 20 patients after 3-4 months; resolution of sustained lung tissue cavities further occurred in 11 patients. At present, a persistent remission of a tuberculous process may be stated in 9 of the 16 patients in whom MSCs were transplanted 1.5-2 years, significant positive bacteriological and morphological changes are observed in 6 patients. Thus, inclusion of transplantation of the autologous MSCs propagated in the culture into a course of antituberculous therapy may be a promising procedure for enhancing the efficiency of therapy in patients with resistant forms of pulmonary tuberculosis.

Morphofunctional study of the therapeutic effect of autologous mesenchymal stem cells in experimental diffuse brain injury in rats.

Effects of systemic transplantation of mesenchymal stem cells obtained by culturing of autologous bone marrow on proliferative activity of cells and functional morphology of neurons after diffuse brain injury were studied in Wistar rats. Comparative analysis of the results indicated that systemic injection of mesenchymal stem cells in a syngeneic organism produced proliferotropic, angiogenic, and, presumably, neurotrophic effects. The therapeutic effect visually manifested on day 2 after intravenous injection of mesenchymal stem cells during the early period of reparative regeneration of ischemic cell and tissue structures of the brain. The neuroprotective effect of mesenchymal stem cells was more pronounced against the background of basic therapy.

Agar cultures of human clonogenic hemopoietic precursor cells for early diagnosis of some myeloproliferative diseases.

Growth characteristics of human hemopoietic cells in erythremia and chronic myeloid leukemia were studied using agar cultures with and without hemopoietic growth factors. Agar cultures, similarly to cultures on other semisolid media (plasma clot, methylcellulose) can be used for early differential diagnosis of polycythemia vera (erythremia) and secondary erythrocytosis: erythremia, but not erythrocytosis, is characterized by spontaneous (erythropoietin-independent) formation of colonies from erythrocyte precursor cells. Spontaneous colony formation from granulocyte-macrophage precursor cells can serve as an important test for early diagnosis of chronic myeloid leukemia. The study of colony formation from granulocyte-macrophage precursors and of the capacity of bone marrow cells to form colonies from hemopoietic stromal precursor cells revealed new characteristics of the studied myeloproliferative diseases. Presumably, spontaneous colony formation from erythrocytic and myeloid precursors should be regarded as a sign of tumor transformation of the studied hemopoietic cells.

Effect of irradiation on colony-forming ability of stem cells from patients with ovarian cancer.

In patients with ovarian cancer, the colony-forming capacity and radiosensitivity of clonogenic tumor cells from the primary node and metastases (ascites) differed considerably.

[New developments in understanding the compensatory hematological reactions and their outcomes in local fractionated therapeutic gamma irradiation]. / Novoe v ponimanii kompensatornykh gematologicheskikh reaktsii i ikh iskhodov pri lokal'nom fraktsionirovannom terapevticheskom gamma-obluchenii.

We have carried out a study of the bone marrow status in both irradiated and non-irradiated zones of 56 patients with stage I-II Hodgkin's disease in complete 9-12 (33 patients, group 1) and 18-23 (23 patients, group 2) year remission after therapeutic irradiation of the supradiaphragmatic lymphatic collectors at a dose of 40 Gy with irradiation of the spleen (33 patients) or splenectomy (23 patients). The total count of myelokaryocytes, myelogram, a relative and absolute content of lymphoid cells, immature granulocytes and elements of erythroid series were calculated in the aspirates from the exposed to radiotherapy sternum and non-irradiated upper portion of the ileum. The number of granulocyte-macrophage (CFU-GM) and stromal (CFU-F) precursor cells were defined using in vitro culture technique. There was a complete annihilation of the bone marrow in the irradiated zones, when the dose exceeded 35 Gy in 3-4 weeks. The concentration of myelokaryocytes, immature granulocytes, erythronormoblasts, CFU-GM, CFU-F in non-exposed bone marrow were significantly lower in all patients of group 2 than in normal subjects and in group 1 patients. Absolute lymphoid count in patients with 18-23 year remission was found to be normal but was considerably reduced in comparison to patients of group 1. These changes may be the result of the previous hyperactivity of the non-irradiated bone marrow which could be a cause of stem cell compartment depletion. The differential calculation of compact and diffuse subpopulations of CFU-F revealed a significant reduction of compact colony-forming CFU-F in both irradiated and unexposed bone marrow. Almost all the stromal precursor cells from irradiated zone formed diffuse colonies in cultures. These results confirm experimental data concerning greater radiosensitivity and proliferative potential of CFU-F, forming compact colonies versus diffuse colony-forming CFU-F. Aplasia of the irradiated bone marrow and hypoplasia of the non-irradiated bone marrow 18-23 years after radiotherapy completion coexisted with normal circulating CFU-GM and granulocyte blood count suggesting a compensatory mechanism involving a mitotic amplification between the progenitor cell and the final differentiated cell.

[The effect of the gas hypoxic mixture GHM-8 on the capacity of the stromal clonogenic cells (CFU-F) in rat bone marrow for postradiation recovery]. / Vliianie gazovoi gipoksicheskoi smesi GGS-8 na sposobnost' stromal'nykh klonogennykh kletok (KOE-F) kostnogo mozga krys k postradiatsionnomu vosstanovleniiu.

The effect of gas hypoxic mixture, containing 8% of O2 (GHM-8), on the ability of cell precursors of haemopoietic stroma (which form colonies (clones) of fibroblasts (CFU-F) in a culture, and are present in the bone marrow of adult rats) to repair potentially lethal and sublethal radiation damages has been investigated. The recovery of CFU-F from potentially lethal damages, that was studied after their delayed survival in a culture following irradiation of animals, proceeds at nearly the same rate in cells irradiated both in the air and in hypoxic conditions (GHM-8). Fractionated irradiation reduces the radioprotective effect of GHM-8 for CFU-F, particularly for the radioresistant subpopulation; the ability of CFU-F to recover from sublethal radiation damages decreases.

[The capacity of rat clonogenic precursor cells of the hemopoietic stroma (CFU-F) to recover from radiation damages]. / Sposobnost' krysinykh klonogennykh kletok-predshestvennikov gemopoéticheskoi stromy (KOE-F) k vosstanovleniiu ot radiatsionnykh povrezhdenii.

The ability of cell precursors of the haemopoietic stroma (CFU-F), that are present in the bone marrow of adult rats, to recover from potentially lethal and sublethal radiation damages has been investigated. The highest reparability, with respect to potentially lethal damages, is displayed by the most radioresistant CFU-F population, that forms loose colonies (clones) in a culture; the slope of the dose-response curve, not the extrapolation number, changes, and heterogeneity of the CFU-F population is observed. The results obtained confirm the presence of heterogeneity in the population of CFU-F, that was revealed in studying their radiosensitivity by the formation of dense and loose fibroblast colonies in a culture.

[Radiosensitivity of cells-precursors of hemopoietic stroma (CFU-F) in the rat bone marrow under the effect of 60Co gamma irradiation in various conditions]. / Radiochuvstvitel'nost' kletok-predshestvennikov gemopoéticheskoi stromy (KOE-F), soderzhashchikhsia v kostnom mozge krys, pri deistvii gama-izlucheniia 60Co v razlichnykh usloviiakh.

Conditions have been developed for cloning cells-precursors of rat bone marrow haemopoietic stroma, that form in culture dense and sparse fibroblast colonies (CFU-F) at a plating efficiency of 10(-4). Radiosensitivity of rat bone marrow CFU-F, with 60Co-gamma-irradiation in vitro, is characterized by the values of Do and n of 1.87 Gy and 1.4 respectively for all clones; 0.65 Gy and 6.7 for dense clones, and 4.27 Gy and 1.0 for sparse clones. This confirms the observed heterogeneity of CFU-F population consisting of highly radiosensitive and radioresistant subpopulations. The parameters of rat bone marrow CFU-F are nearly the same with irradiation both in vivo and in vitro; with in situ irradiation, the oxygen effect comes into play in a radiosensitive subpopulation of CFU-F; the OER values are 1.6, 2.6 and 0.9 for all, dense and sparse clones respectively.

[The radioprotective effect of hypoxia on clonogenic cells of rat bone marrow stroma (KOE-F)]. / Radiozashchitnoe deistvie gipoksii na klonogennye kletki stromy kostnogo mozga (KOE-F) krys.

A comparative study was made on the survival rate of cell-precursors of haemopoietic stroma, that form, in a rat bone marrow culture, colonies (clones) of fibroblasts (CFU-F) after gamma-irradiation of animals in the air or in a gas hypoxic mixture, containing 8% of O2 (GHM-8). Irradiation in GHM-8 was shown to increase the survival rate of CFU-F by 1.7 times (as compared to exposure in the air) as estimated by the total number of colonies that are formed in a culture; the radioprotective effect of GHM-8 was more pronounced for CFU-F which form dense colonies: DMF for dense and loose clones was 2.4 and 1.6 respectively.

[The granulocyte-macrophage colony stimulating factor and the radiation protective effect of yeast mannan]. / Stimuliruiushchii granulotsitarno-makrofagal'nyi rostok i radiozashchitnyi éffekty drozhzhevogo mannana.

The effect of mannan polysaccharide on the haemopoiesis recovery in irradiated mice has been investigated. Mannan has been shown to exert both the protective and the stimulatory effect: it accelerates restoration of femur bone marrow cellularity and nucleate cell number in the peripheral blood and causes a larger initial yield and subsequent more rapid postirradiation dynamics of pluripotent haemopoietic stem cells and precursor cells of granulocytes and macrophages.

[Patterns in the combined action of irradiation and glucose loading on tumor cells]. / Zakonomernosti kombinirovannogo deistviia oblucheniia i gliukoznoi nagruzki na opukholevye kletki.

It was shown that incubation of Ehrlich ascites tumor cells with glucose or in buffer solutions of low pH decreases their viability. The cell survival rate depends on pH values irrespective of the protoxidation method and oxygenation conditions used. At the same time, radiosensitivity of Ehrlich ascites tumor cells is practically invariable with pH being decreased from 7.0 to 5.0. The effects of glucose and radiation are additive in conditions simulating the effect of hyperglycaemia in vivo.

[Comparative radiosensitivity of clonogenic tumor cells of the transplantable Ehrlich carcinoma in the ascitic and solid forms of growth]. / Sravnitel'naia radiochuvstvitel'nost' klonogennykh opukholevykh kletok perevivaemogo raka Erlikha pri astsitnoi i solidnoi forme rosta.

Survival of clonogenic cells of solid Ehrlich ascites tumor (EAT) exposed to 60Co-gamma-radiation in vitro under the oxygenation conditions was investigated and the clonogenic capacity and radiosensitivity of these cells and cells of the previously studied EAT ascitic form and Lewis solid tumor comparatively studied to elucidate how the efficiency of colony formation (ECF) would affect their radiosensitivity. ECF for solid EAT cells was 2.6 +/- 0.3%, which was lower, by about an order of magnitude, than that for ascitic form of this tumor and was nearly the same as that for Lewis tumor cells. A median cell lethal dose (D0) was practically the same for all tumors under study. It is suggested that the differences in ECF do not substantially influence the radiosensitivity of clonogenic cells of the studied tumors.

[Thermosensitivity of clonogenic cells and the induction of thermal tolerance]. / Termochuvstvitel'nost' klonogennykh kletok i induktsiia v nikh termotolerantnosti.

Clonogenic cells of some normal tissues (CFU-GM of the bone marrow of mice, CFU-F of the bone marrow of rats, CFU-GM and CFU-F of the bone marrow of dormice) as well as tumor clonogenic cells of the ascitic variant of ascitic Ehrlich carcinoma were characterized by similar thermosensitivity during their heating under in vitro conditions whereas thermosensitivity in clonogenic cells of solid tumors (LLC, solid Ehrlich ascitic carcinoma) turned out twice as high. A possibility of inducing thermotolerance in these cells by various modes was shown.

[Clonogenic capacity and proliferative activity of the cells of malignant tumors of the bones]. / Klonogennaia sposobnost' i proliferativnaia aktivnost' kletok zlokachestvennykh opukholei kostei.

The authors presented their first results of tumor cell cloning in 48 patients with malignant bone tumors. Colony growth was observed in 32 patients. Colony formation efficacy, expressed in the number of grown colonies per 10(5) tumor cells incubated in the culture, varied greatly (from 0.4 to 90.7) in different patients. Rather a high colony forming capacity of tumor cells was prognostically unfavorable. Tumor cells in the patients with malignant bone tumors were characterized by a low proliferative activity: the ratio of DNA-synthesizing cells evaluated by immunofluorescence or flow cytometry in 14 examinees was an average of 3.3% varying in different patients from 0 to 8.0%. No distinct correlation between tumor cell colony forming capacity and proliferative activity was revealed in the patients.