Search

Background: Bone marrow-derived cells may play a role in tissue injury and repair. Growth factors facilitate the mobilization of bone marrow-derived cells to the site of injury. Objectives: The aim of this study was to determine the effect of the mobilization of autologous bone marrow-derived cells by granulocyte colony-stimulating factor (CSF3) on bleomycin-induced lung injury in mice. Methods: The bone marrow from male green fluorescent protein transgenic (C57Bl/6J) mice was transplanted into irradiated female C57Bl/6J mice. Bleomycin lung injury was induced in these bone marrow-reconstituted mice and unreconstituted C57Bl/6J mice, and some mice were treated with recombinant CSF3. Lung histology, survival, cytokine expression and matrix metalloproteinase (MMP) expression were evaluated to determine the effect of CSF3 after bleomycin-induced lung injury. Results: Histology and flow cytometry analysis showed successful mobilization of bone marrow-derived cells by CSF3 treatment in the recipient lungs. Importantly, CSF3 attenuated bleomycin-induced lung injury and improved survival. Furthermore, CSF3 administration regulated transforming growth factor-β, interferon-γ, MMP9 and tissue inhibitors of MMP1 expression during bleomycin injury. Conclusions: These data demonstrated that the mobilization of bone marrow-derived cells by CSF3 has a protective effect against bleomycin-induced lung injury and fibrosis.

Feeder cells are usually used in culturing embryonic stem cells (ESCs) to maintain their undifferentiated and pluripotent status. To test whether mouse embryonic stem cells (mESCs) may be a source of feeder cells to support their own growth, 48 fibroblast-like cell lines were isolated from the same mouse embryoid bodies (mEBs) at three phases (10th day, 15th day, 20th day), and five of them, mostly derived from 15th day mEBs, were capable of maintaining mESCs in an undifferentiated and pluripotent state over 10 passages, even up to passage 20. mESCs cultured on the feeder system derived from these five cell lines expressed alkaline phosphatase and specific mESCs markers, including SSEA-1, Oct-4, Nanog, and formed mEBs in vitro and teratomas in vivo. These results suggest that mEB-derived fibroblasts (mEB-dFs) could serve as feeder cells that could sustain the undifferentiated growth and pluripotency of their own mESCs in culture. This study not only provides a novel feeder system for mESCs culture, avoiding a lot of disadvantages of commonly used mouse embryonic fibroblasts as feeder cells, but also indicates that fibroblast-like cells derived from mESCs take on different functions. Investigating the molecular mechanisms of these different functional fibroblast-like cells to act on mESCs will contribute to the understanding of the mechanisms of mESCs self-renewal.

To investigate the contribution of mobilized autologous bone marrow-derived cells (BMDC) to lung repair after lung injury induced by bleomycin, and the mechanisms of any protective effects conferred by BMDC.Sixty marrow-reconstructed mice were randomly divided into 2 groups: group A [bleomycin + granulocyte colony stimulating factor (G-CSF)] and group B (bleomycin + saline). Seventy-five normal mice were randomly divided into 3 groups: group C (bleomycin + G-CSF); group D (bleomycin + saline) and group N (saline only). Each group was further divided into 3 subgroups, which were sacrificed respectively on days 3, 7 and 14. Therapeutic evaluations were made by means of HE stain, Masson's trichrome stain, hydroxyproline concentration and pulmonary permeability index. The expressions of TGF-beta(1), IFN-gamma, MMP-9 and TIMP-1 in the lung tissue were detected by immunohistochemistry. Intrapulmonary BMDC was evaluated by flow cytometry and laser scanning confocal microscope. Another 20 mice were randomly divided into 2 groups including group E (bleomycin + G-CSF) and group F (bleomycin + saline). The survival time of each mouse was observed without end point.The alveolitis score (mean rank 15.3), the pulmonary fibrosis score (46 +/- 8), the hydroxyproline concentrations (0.44 +/- 0.09) microg/mg, the TGF-beta(1) level (111 +/- 23), the IFN-gamma level (250 +/- 72) and the MMP-9 level (59 +/- 19) were significantly decreased in reconstructed treatment group on day 7 as compared to reconstructed control group, which was respectively (mean rank 28.0), (73 +/- 10), (0.52 +/- 0.07) microg/mg, (161 +/- 35), (299 +/- 31) and (314 +/- 77). Likewise, the alveolitis (mean rank 22.7), the pulmonary fibrosis (27 +/- 15), the hydroxyproline concentrations (0.41 +/- 0.05) microg/mg, the pulmonary permeability index (43.8 +/- 9.9) x 10(-3), the TGF-beta(1) level (132 +/- 55), the IFN-gamma level (178 +/- 23), and the MMP-9 level (101 +/- 54) in non-reconstructed treatment group on day 7 were significantly lower than those in non-reconstructed control group, (mean rank 33.9), (56 +/- 13), (0.49 +/- 0.08) microg/mg, (54 +/- 9) x 10(-3), (320 +/- 98), (409 +/- 61), (288 +/- 75), the differences being statistically significant (P0.05). The intrapulmonary BMDC level of reconstructed treatment group (0.65 +/- 0.13) was significantly higher than that in reconstructed control group (0.46 +/- 0.11), P0.05.Mobilization of BMDC by G-CSF showed a protective effect on lung injury induced by bleomycin in mice, but did not have significant influence on survival time.

As the lymphocytes of immuno-mediated aplastic anemia (IMAA) are in active state, and the hematopoietic stem cells are in silence, this study was aimed to design a new strategy to treat IMAA. To utilize the difference of radiosensitivity between active lymphocytes and silent hematopoietic stem cells, the animals suffered from IMAA were treated with a single low dose of irradiation, killing the active lymphocytes to release its suppression to hematopoietic stem cells without injuring the hematopoietic stem cells. Therefore, the hematopoiesis can be restored. Experiments were completed in IMAA mouse model. At day 4 after making IMAA, the model mice were giren total body irradiation of 150 cGy, the non-treated model mice and normal mice irradiated with 150 cGy were used as control. The survive time and survive rate of mice, blood picture, the account of nucleated cell of bone marrow, and pathological changes of bone marrow and lymphoid tissues of each group mice were observed. The results were as follows: (1) Survive rate of IMAA mice in non-treated group was 12.5%, the average survive time was 27.4 +/- 13.4 days. 100% of IMAA mice in irradiation-treated group survived over 60 days. The mice of irradiation control group all survived. (2) The account of WBC of IMAA mice in non-treated group dramatically decreased until to die, and in the irradiation-treated group it was gradually increased since the 10th day after treatment and close to normal level at the 28th day. (3) The RBC hematocrit of IMAA mice in non-treated group progressively decreased at day 14, and IMAA mice of irradiation-treated group gradually recovered closely to normal level after slightly fall at day 14, similar to the mice of irradiation control group. (4) The account of nucleated cells of bone marrow in non-treated IMAA mice dramatically decreased, and in the IMAA mice of the irradiation-treated group it was rapidly increased following transient fall, and restored to normal. (5) Pathological observations showed that the bone marrow and spleen of non-treated IMAA mice demonstrated typical aplastic anemia pattern, including bone marrow failure, marked splenatrophy, but the bone marrow and lymphoid tissues in the IMAA mice of irradiation-treated group were recovered to normal at day 28 after treatment. It is concluded that the low dose of irradiation displayed a significant therapeutic effect to IMAA mice, their hematopoisis could be completely restored to normal. The mechanism of therapeutic effect may contribute to low dose of irradiation killing the immunocompetent lymphocytes, therefore, suppressing hematopoiesis. The experiment results not only set up a new strategy for IMAA treatment, but also provided a clue to study the mechanism of IMAA.

In previous studies, progenitor embryoid body-derived (EBD) cells have been derived from human embryonic germ cells. These cells express lineage markers of three primary germ layers, although their potential to produce true fetal cells of various types has yet to be tested. To this end, we have transplanted EBD cells into the fetal sheep liver. We show that these cells respond appropriately to environmental cues and give rise to hepatocytes and well-structured bile ducts. These results suggest that EBD cells are relatively uncommitted early progenitors capable of effective incorporation and differentiation in vivo. The ability to generate functional liver cells makes EBD cells potentially useful for cell therapy.

AIM: To study the effect of retrorsine on mouse he-patocyte proliferation. METHODS: Mice and rats were treated respectively with two injections of retrorsine (as retrosine-treated group) or saline (as non-treated group) at 2 wk intervals. They received a single injection of carbon tetrachloride (CCl4) 4 wk later. On d 0, 1, 2, 3, 4, 6, 15 after CCl4 administration, the animals were killed and their livers were excised. Hematoxylin and eosin (HE) staining and Ki-67 antibody immunohistochemical analysis of liver samples were used to evaluate the pathological changes and hepatocyte proliferation. RESULTS: In rats treated with retrorsine and CCl4, the liver displayed obvious megalocytosis, proliferation of mild bile duct, small hepatocyte-forming nodule, which were not found in liver samples from non-treated group. However, in mice treated with retrorsine combined with CCl4, the liver displayed hepatocyte degeneration and necrosis in perivenous areas. There was no obvious difference between retrorsine-treated group and non-treated group. Ki-67 immunohistochemical analysis showed that in rats treated with retrorsine, the positive hepatocytes mainly found in small hepatocyte nodules, were obviously less than those in non-treated group. The mice treated with retrorsine showed that the number of Ki-67 positive hepatocytes was very high and more than that in non-treated group. CONCLUSION: Retrorsine has no effect on mouse hepatocyte proliferation.

In order to establish a objective method of analysis in the case of sulfured hydrogen poison.The sulfured hemoglobin of the biomaterials(blood) were investigated by the spectrophotometry.Results showed that sulfured hemoglobin had a specific absorbance peak at 612 nm, it is a linear relationship about the absorbancity to the concentration of sulfured hemoglobin.It is possible to mark the poison degree by the spectrophotometery.

To solve the problem of immune incompatibility, nuclear transplantation has been envisaged as a means to produce cells or tissues for human autologous transplantation. Here we have derived embryonic stem cells by the transfer of human somatic nuclei into rabbit oocytes. The number of blastocysts that developed from the fused nuclear transfer was comparable among nuclear donors at ages of 5, 42, 52 and 60 years, and nuclear transfer (NT) embryonic stem cells (ntES cells) were subsequently derived from each of the four age groups. These results suggest that human somatic nuclei can form ntES cells independent of the age of the donor. The derived ntES cells are human based on karyotype, isogenicity, in situ hybridization, PCR and immunocytochemistry with probes that distinguish between the various species. The ntES cells maintain the capability of sustained growth in an undifferentiated state, and form embryoid bodies, which, on further induction, give rise to cell types such as neuron and muscle, as well as mixed cell populations that express markers representative of all three germ layers. Thus, ntES cells derived from human somatic cells by NT to rabbit eggs retain phenotypes similar to those of conventional human ES cells, including the ability to undergo multilineage cellular differentiation.

To explore the effect of bone morphogenetic protein (BMP) to activate mesenchymal stem cells of skeletal muscle for rescuing bone marrow failure.The study was performed on lethal rat acute aplastic anemia model induced by combined 5-fluorouracil (5-FU) and busulfan. The rh-BMP-2 was implanted into the thigh muscle of the rats at 3 days before aplastic anemia was induced. In the control group the rats were implanted with agar into the thigh muscle. The blood picture, pathologic changes and the mortality in two groups were observed. At the same time, rh-BMP-2 were implanted into the thigh muscle of normal Kun-min mice for dynamic control observation of the implantation local morphological changes, colony forming units-spleen (CFU-S) and stem cell growth factor (SCF) expression of the stroma cells of ectopic ossicles induced by BMP.At 7 days after BMP implantation in the mice the mesenchymal cells around BMP in muscle proliferated, and appeared in bone marrow to form an ectopic ossicles. The SCF expression of stroma cells in ectopic ossicles were higher than that of self-bone marrow. 56.3% of BMP-treated aplastic rats were survived over 3 months and its hematopoiesis was completely reconstituted and the histo-morphological picture of the spleen and bone marrow were recovered to normal. But in the control group only one of 23 rats was survived, the remainder died of hematopoietic failure.BMP-implantation into the skeletal muscle could rescue the bone marrow hematopoietic failure. The mechanism might be related to the BMP activated auto-mesenchymal cells of skeletal muscles to direct hematopoietic cell differentiation. In our hands it might create a new pathway for utilization of auto-muscle derived mesenchymal cells to reconstitute hematopoiesis.

Using transplantable erythroblastic leukemia cells of EL9611(H-2d), the cells were inoculated to CB6F(1)(H-2d/b) generation of BALB/c x C57BL/6 mouse, the biological characterization of erythroblastic leukemia in haploidentical mouse was studied, that provides an experimental model for the study of graft-versus leukemia (GVL) with bone marrow or stem cell transplantation. When 10(3) - 10(8) of the spleen cells of EL9611(H-2d) had been intravenously inoculated to CB6F(1) mouse, the erythroblastic leukemia cells were transplanted successively and the F(1) generation of erythroblastic leukemia model in mice was established with 100% incidence of erythroblastic leukemia. There was a linear relationship between the survival time and the number of leukemic cell. The survival time of the mice was (9.6 +/- 0.8) days when 10(6) cells were inoculated. If the CB6F(1) mouse was transplanted successively for four generations, the incidence was 100%. The main targets for the leukemic EL9611(H-2d) cells were liver, spleen and marrow. The reaction of the erythroblastic leukemia cells for hemoglobin staining was positive, while the peroxidase reaction was negative. These cells were sensitive to some chemotherapeutic drugs, such as cytosine arabinoside and cyclophosphamide. This study presents the convenience for the studies on the GVL with haplo-allogeneic transplantation, in the F(1) generation of erythroblastic leukemia model of the commonly-used CD57BL/6 x BALB/c mouse.