Bone Marrow-derived Multipotent Stem Cells Research Articles

Therapeutic strategies involving uterine stem cells in reproductive medicine.

The current review provides an update on recent advances in stem cell biology relevant to female reproduction. Stem cells are undifferentiated cells that often serve as a reservoir of cells to regenerate tissue in settings or injury or cell loss. The endometrium has progenitor stem cells that can replace all of the endometrium during each menstrual cycle. In addition, multipotent endometrial cells replace these progenitor cells when depleted. Recruitment of stem cells from outside of the uterus occurs in setting of increased demand such as ischemia or injury. Bone marrow-derived multipotent stem cells are recruited to the uterus by estrogen or injury-induced expression of the chemokine CXCL12. In the setting of overwhelming injury, especially in the setting of low estrogen levels, there may be insufficient stem cell recruitment to adequately repair the uterus resulting in conditions such as Asherman syndrome or other endometrial defects. In contrast, excessive recruitment of stem cells underlies endometriosis. Enhanced understanding of stem-cell mobilization, recruitment, and engraftment has created the possibility of improved therapy for endometrial defects and endometriosis through enhanced manipulation of stem-cell trafficking. Further, the normal endometrium is a rich source of multipotent stem cells that can be used for numerous applications in regenerative medicine beyond reproduction. A better understanding of reproductive stem-cell biology may allow improved treatment of endometrial disease such as Asherman syndrome and other endometrial receptivity defects. Inhibiting stem-cell mobilization may also be helpful in endometriosis therapy. Finally, endometrial derived multipotent stem cells may play a crucial role in cell therapy for regenerative medicine.

05 Nox2-derived oxidative stress and bone marrow-derived hematopoietic stem cell dysfunction in middle-age obesity

Systematic oxidative stress is a characteristic of metabolic disorders and cardiovascular diseases associated with middle-age obesity. Bone marrow-derived multi-potent stem cells (BMSC) hold the hope in regenerating damaged tissues; however, the effect of oxidative stress on BMSC function remains unknown. In this study, we investigated the BMSC function in mouse models of middle-age obesity. Littermates of C57BL/J6 wild-type and Nox2 (an O2.–generating enzyme) knockout mice (7 m old, n=15) were fed with high fat diet (HFD, 45% kcal fat, 20% kcal protein and 35% kcal carbohydrate) or normal chow diet (NCD, 12% kcal fat, 28% kcal protein and 60% kcal carbohydrate) for 16 weeks. BMSCs were isolated from mice at 11 m of age. Compared to NCD controls, the numbers of CD133+/VEGFR2+ endothelial progenitor cells (EPC) were significantly decreased (2.2%±0.3 NCD vs. 0.8%±0.5 HFD) in HFD mice. There were significant increases (82±9.2 %) in the levels of O2.- production by HFD BMSC, and this was accompanied with accelerated cell proliferation (160±5.2%), cell cycle progression from G1/G0 phase to S phase, and significant increases in cell apoptosis (6.9±2.5% NCD vs. 29.8±8.2% HFD) as examined by annexin V flow cytometry. Moreover, the levels of PCNA and p53 expression were significantly increased in HFD BMSC. However, all these changes were absent in BMSC isolated from Nox2 knockout mice fed with HFD. In conclusion, an obesity environment activates Nox2 and oxidative stress damages BMSC function and reduces EPC population. Nox2 may present a therapeutic target for the prevention and treatment of obesity-related diseases.

Electric impedance sensing in cell-substrates for rapid and selective multipotential differentiation capacity monitoring of human mesenchymal stem cells

Biosensor systems which enable impedance measurements on adherent cell layers under label-free conditions are considered powerful tools for monitoring specific biological characteristics. A radio frequency identification-based sensor platform was adopted to characterize cultivation and differentiation of human bone marrow-derived multipotent stem cells (bmMSC) over periods of up to several days and weeks. Electric cell-substrate impedance sensing was achieved through fabrication of sensitive elements onto glass substrates which comprised two comb-shaped interdigitated gold electrodes covering an area of 1.8mm×2mm. The sensing systems were placed into the wells of a 6-well tissue culture plate, stacked onto a reader unit and could thus be handled and operated under sterile conditions. Continuous measurements were carried out with a sinusoidal voltage of 35mV at a frequency of 10kHz.After seeding of human bmMSC, this sensor was able to trace significant impedance changes contingent upon cell spreading and adhesion. The re-usable system was further proven suitable for live examination of cell-substrate attachment or continuous cell monitoring up to several weeks. Induction of either osteogenic or adipogenic differentiation could be validated in bmMSC cultures within a few days, in contrast to state-of-the-art protocols, which require several weeks of cultivation time. In the context of medical cell production in a GMP-compliant process, the here presented interdigitated electric microsensor technology allows the documentation of MSC quality in a fast, efficient and reliable fashion.

Biocompatibility of Calcium Phosphate Ceramics Synthesized from Eggshell

The aim of this paper was the HA and β-TCP powers were synthesized by a new wetchemical method using eggshell and phosphoric acid. The biocompatibility of synthesized natural HA, HA/β-TCP(50:50) and β-TCP derived from eggshell was compared with those of as commercial chemical powder with mesenchymal stem cells derived from human bone marrow. Development of crystalline phases of the mixtures was studied as functions of mixing ratio and temperature using X-ray diffractometer. The morphological characteristics of the calcined eggshell and synthesized powders were examined by scaning electron microscopy. The in-vitro cytotoxicity and cell attachment of sintered disks were examined using human bone marrowderived multipotent stem cells(hBMSCs). Cell response was characterized by MTT assay , Alkaline phosphatase stain and RT-PCR analysis. Pure HA was synthesized in the mixing ratio of 1:1.1 wt% at 900°C for 1h. the crystallization of HA was started at 800°C in the 1:1.1 mixing ratio, ant the HA phase was continued up to the high temperatures. In the ratio of 1:1.3 and 1:1.5 wt%, β-TCP was effectively synthesized at 900°C. In the 1:1.5 ratio, β-TCP phase was detected at 700°C, and complete crystallized β-TCP was observed above 900°C. At the higher temperature than 1000°C, the β-TCP was gradually decreased and α-TCP was observed. The HA and β-TCP disk does not exert cytotoxic effect on the hBMSCs undergoing osteoblastic differentiation. In addition, the hBMSCs are adhered on the surface of synthesized natural HA and β-TCP disk as successfully as on the culture plate or as commercial chemical HA and β-TCP disk. The hBMSCs adhered on either synthesized natural HA, β-TCP or as commercial chemical HA, β-TCP disk displays undistinguishable actin arrangement and cellular phenotypes, indicating that synthesized natural HA, β-TCP does not disrupt normal cellular responses. Analysis of differentiation of the hBMSCs cultured on culture plate, synthesized natural HA, β-TCP and as commercial chemichal HA, β-TCP disk shows that three matrices are able to support osteoblastic differentiation of the hBMSCs as accessed by alkaline phosphatase staining.

Derivation and characterization of bone marrow-derived multipotent stem cells

We have identified a subpopulation of stem cells within adult human bone marrow (BM), isolated at the single-cell level, that self-renew without loss of multipotency for more than 6 to 9 months of continuous cultures and exhibit the capacity for differentiation into cells of three germ layers [1]. Based on surface marker expression, these clonally expanded human bone marrow-derived multipotent stem cells (hBMSCs) do not appear to belong to previously described BM-derived stem or progenitor cell populations.