Objective To review research progress of adipose tissuederived stromal cells (ADSCs).Methods The recent articles on ADSCs were extensively reviewed, and the culture and differentiation ability of ADSCs were investigated.Results A population of stem cells could be isolated from adult adipose tissue, they were processed to obtain a fibroblast-like population of cells and could be maintained in vitro for extended periods with stable population doubling. The majority of the isolated cells were mesenchymal origin, with a few pericytes,endothelial cells and smooth muscle cells. ADSCs could be induced to differentiate intomultiple mesenchymal cell types, including osteogenic, chondrogenic, myogenic and adipogenic cells, they could also differentiate into nerve cells.Conclusion ADSCs can substitute mesenchymal stem cells and become an alternative stem cells source for tissue engineering.
Objective To investigate the myogenic differentiation of mesenchymal stem cells (MSCs) after being transplanted into the local muscle tissues. Methods The serious muscleinjured model was established by the way of radiation injury, incising, and freezing injury in 36 mouses. Purified MSCs derived from bone marrow of male mouse and MSCs induced by5-azacytidine(5-Aza-CR) were transplanted into the local of normal muscle tissues and injured muscle tissues of femal mouse. The quantity of MSCs and the myogenic differentiation of implanted MSCs were detected by the method of double labeling, which included fluorescence in situ DNA hybridization (FISH) and immuno-histochemistry on the 1st, 3rd, 6th, 9th, 12th, and 15th day after transplantation. Results The quantity of implanted MSCs decreased as timepassed. MSCs’ differentiation into myoblasts and positive expression of desmin were observed on the 15th day in purified MSCs group and on the 6th day in induced MSCs groups. Conclusion MSCs could differentiate into myoblasts after being implanted into the local of muscle tissues. The differentiationoccurs earlier in the induced MSCs group than that in purified MSCs group.
OBJECTIVE: To investigate the characteristic and phenotype of ectomesenchymal stem cells of human fetal facial processes and the procedure of spontaneous differentiation to smooth muscle cells. METHODS: The primary ectomesenchymal cells of E 50 human fetal facial processes were isolated by 2.5 g/L trypsin and cultured with DMEM/F 12 with 10(-6) U/L leukemia inhibitor factor(LIF). The morphology and growth rate were observed by inverted microscop. After being withdrawn LIF, the characteristic of cells were identified by immunohistochemistry and RT-PCR. Ultrastructure was observed by transmission electron microscope. RESULTS: The cultured cells displayed monolayer growth and were fibroblast-like with 2-4 processes. The cells were stainely positived for anti-human natural killer cell marker-1, Vimentin, S-100, neuron specific enolase, myoglobin and VIII factor, but negatively for glial fibrillary acidic protein, neural fiblament, alpha-SMA and cytokeratin in immunohistochemistry. Two days after being withdrawn the LIF, cells expressed alpha-SMA in protein and mRNA levels. The cells were rich in muscular filament-like structure and dense bodies under transmission electron microscope. CONCLUSION: Cultured cells are undifferentiated ectomesenchymal stem cells. The cells have the potential for differentiating spontaneously to smooth muscle cell.
Objective To investigate the feasibility of differentiation of the marrow mesenchymal stem cells (MSCs) into the cells of the skin appendages andthe mechanism of their involvement in the wound healing. Methods The bone marrow was collected from Wistar rats by the flushing of the femurs, MSCs were isolated and purified by the density gradient centrifugation. Then, the MSCs were amplified and labelled with 5-bromo-2′-deoxyuridine (BrdU). The full-thickness skin wounds with an area of 1 cm×1 cm were made on the midback of the homogeneous male Wistar rats. At the same time, 1×106/ml BrdU-labelled MSCs were infused from thepenile vein. The specimens were harvested from the wound tissues on the 3rd dayand the 7th day after operation and were immunohistochemically stained by either BrdU or BrdU and pan-keratin. Results The BrdU positive cells appeared in thehypodermia, the sebaceous glands, and the hair follicles of the wounds, as wellas the medullary canal of the femurs. The double-staining showed the BrdU positive cells in the sebaceous glands and the hair follicles of the wounds expressedpan-keratin simultaneously. Conclusion During the course of the wound healing, MSCs are involved in the wound repair and can differentiate into the cells ofthe skin appendages under the microenvironment of the wound.
Objective To investigate the possibility of theadipose tissue-derived stromal cells(ADSCs) to differentiate into the neuron-like cells and to explore a new cell source for the transplantation related to the central nervous system. Methods Adipose was digested by collagenase, cultured in the fetal bovine serum containing a medium. Trypse was used to digest the cells and the cell passage was performed. The 3rd to the 9th passage ADSCs were used to make an induction. Isobutylmethylxanthine, indomethacin, insulin, and dexamethasone were used to induce the ADSCs to differentiate into the neuron-like cells and adipocytes. Sudan black B and immunocytochemistry were used to identify the cells. Results A population of the ADSCs could be isolated from the adult human adipose tissue, they were processed to obtain a fibroblast-like population of the cells and could be maintained in vitro for an extendedperiod with the stable population doubling, and they were expanded as the undifferentiated cells in culture for more than 20 passages, which indicated their proliferative capacity. They expressed vimentin and nestin, and characteristics of the neuron precursor stem cells at an early stage of differentiation. And the majority of the ADSCs also expressed the neuron-specific enolase and βⅢ-tubulin, characteristics of the neurons. Isobutyl-methyxanthine, indomethacin, insulin, and dexamethasone induced 40%-50% of ADSCs to differentiate into adipocytes and 0.1%0.2% of ADSCs into neuron-like cells. The neuron-like cells had a complicated morphology of the neurons, and they exhibited a neuron phenotype, expressed nestin, vimentin, neuron-specific enolase and βⅢ-tubulin, but some neuron-like cells also expressed thesmooth muscle actin (SMA), and the characteristics of the smooth muscle cells; however, the neurons from the central nervous system were never reported to express this kind of protein. Therefore, the neuron-like cells from the ADSCs could be regarded as functional neurons. Conclusion Ourresults support the hypothesis that the adult adipose tissue contains the stem cells capable of differentiating into the neuron-like cells, and they can overcome their mesenchymal commitment, which represents an alternative autologous stemcell source for transplantation related to the central nervous system.
Objective To investigate the division, prol iferation and differentiation abil ities of nestin+/GFAP+cell after spinal cord injury and to identify whether it has the characteristic of neural stem cells (NSCs). Methods Twelvemale SD rats, aged 8 weeks and weighing 200-250 g, were randomized into 2 groups (n=6 per group): model group inwhich the spinal cord injury model was establ ished by aneurysm cl ip compression method, and control group in which no processing was conducted. At 5 days after model ing, T8 spinal cord segment of rats in each group were obtained and the gray and the white substance of spinal cord outside the ependymal region around central tube were isolated to prepare single cellsuspension. Serum-free NSCs culture medium was adopted to culture and serum NSCs culture medium was appl ied to induce differentiation. Immunohistochemistry detection and flow cytometry were appl ied to observe and analyze the type of cells and their capabil ity of division, prol iferation and differentiation. Results At 3-7 days after injury, the model group witnessed a plenty of nestin+/GFAP+ cells in the single cell suspension, while the control group witnessed few. Cell count of the model and the control group was 5.15 ± 0.71 and 1.12 ± 0.38, respectively, indicating there was a significant difference between two groups (P lt; 0.01). Concerning cell cycle, the proportion of S-phase cell and prol iferation index of the model group (15.49% ± 3.04%, 15.88% ± 2.56%) were obviously higher than those of the control group (5.84% ± 0.28%, 6.47% ± 0.61%), indicating there were significant differences between two groups (P lt; 0.01). In the model group, primary cells gradually formed threedimensional cell clone spheres, which were small in size, smooth in margin, protruding in center and positive for nestin immunofluorescence staining, and large amounts of cell clone spheres were harvested after multi ple passages. While in the control group, no obvious cell clone spheres was observed in the primary and passage culture of single cell suspension. At 5 days after induced differentiation of cloned spheres in the model group, immunofluorescence staining showed there were a number of galactocerebroside (GaLC) -nestin+ cells; at 5-7 days, there were abundance of β-tubul in III-nestin+ and GFAP-nestin+ cells; and at 5-14 days, GaLC+ ol igodendrocyte, β-tubul in II+ neuron and GalC+ cell body and protruding were observed. Conclusion Nestin+/GFAP+ cells obtained by isolating the gray and the white substance of spinal cord outside the ependymal region around central tube after compressive spinal cord injury in adult rat has the abil ity of self-renewal and the potential of multi-polarization and may be a renewable source of NSCs in the central nervous system.
Objective To study the effect of core-binding factor α1(Cbfa1)on the mesenchymal stem cells(MSCs) osteoblastic differentiation.Methods The MSCs were isolated from Japan white rabbits and cultured in vitro. The 3rd generation MSCs were infected with Cbfa1 recombinant adenovirus. The expression of Cbfa1 was detected by immunofluorescence after being infected for 3 days and the proliferation was estimated by MTT method from the 1st day to the 7th day. Then the MSCs were divided into four groups: the commonly cultured group, the simply induced group, the control adenovirus treatment group, and the Cbfa1 adenovirus treatment group. The expressions of mRNA for a various of osteoblast gene markers such as alkaline phosphatase, osteocalcin, osteopontin and type I collagen were analyzed based on reverse transcriptase polymerase chain reaction (RT-PCR). The change of adipose and myoblastic differentiation gene marker PPARγ2 and MyoD expression were detected by RT-PCR respectively.Results Positive staining of Cbfa1 was found in the MSCs infected with Cbfa1 adenovirus, and there was no significant difference in cell proliferation among the experimental groups（Pgt;0.05）. The RT-PCR indicated that all the osteoblast gene markers except type I collagen were up-regulated in the Cbfa1 adenovirus treatment group. In contrast, the expressions of PPARγ2 and MyoD were restrained. Conclusion Cbfa1 can directly promote the differentiation of MSCs into osteoblasts.
【Abstract】 Objective To explore a method to identify the sensory and motor fascicles in peri pheral nervetrunk. Methods Thirty Wistar rats were selected to obtain whole spine. The spinal gangl ion, its dorsal root and ventral root,and sciatic nerve were harvested, Annexin V and Agrin specificities were observed with Western blot. In the experimental group,anterior branch and posterior branch of spinal nerve, sciatic nerve, and its muscular branch and cutaneous branch were harvested from 15 rats to make the observation of immunohistochemistry. In the other 15 rats, first antibody was replaced by PBS as control group. Different nerve fascicles were studied with Micro Raman scattering technique in 16 12-month-old New Zealand rabbits. Results The Annexin V and Agrin were special substances of sensory and motor nerves respectively and can act as specific antigens for identifying different nerve fascicles. There were significant differences in the intensity and breadth of the peak of the spectral properties between motor and sensory fascicles at frequencies of 1 088, 1 276, 1 439, 1 579 and 1 659 cm-1 .The peak intensity ratios of 1 276 to 1 439 cm-1 were 0.95±0.06 in motor nerve fascicles and 1.17±0.08 in sensory fascicles, showing significant differences (P lt; 0.05). Conclusion The Micro Raman spectra is more effective than immunohistochemistry in identifying different nerve fascicles, and it possesses as feasibil ity for cl inical appl ication.
Objective To review the research progress of mesenchymal stem cells (MSCs) in burn wound repair. Methods The recent literature about MSCs involved in burn wound repair and mechanism was extensively reviewed and analyzed. Results MSCs have the capacity of self-renew, rapid proliferation, differentiation and paracrine, and promote burn wound repair through differentiating into a series of skin wound cells and regulating wound microenvironment. Conclusion MSCs have great potentials in the burn field. However, the cell survival and outcome are also facing challenges from poor microenvironment of the burn wound.
Objective Bone marrow mesenchymal stem cells (BMSCs) are multi potent and thus are able to differentiate into a number of different cell types under certain culture condition. However, the effect of age on the differentiation remains unknown. To explore the effect of the microenvironment formed by Schwann cells (SCs) on BMSCs differentiation into neurons and ol igodendrocytes in rats at different ages in vitro. Methods SCs were extracted and purified from the distal sciatic nerves of neonatal Wistar rats. BMSCs were isolated from bone marrow of Wistar rats (aged 1 month, 6 months, and 12 months, respectively) and cultured in vitro. The cells were identified by immunofluorescent staining. The BMSCs at passage 2 were labeled by PKH26 and cocultured with SCs at passage 3 in equal proportions in two layer Petri dish. According to the BMSCs from the rats at different ages, experiment was divided into 3 groups: SCs were cocultured with 1-month-old rat BMSCs (group A), 6-month-old rat BMSCs (group B), and 12-month-old rat BMSCs (group C), respectively. The morphological changes of cocultured BMSCs were observed by inverted phase contrast microscope, the expressions of neuron-specific enolase (NSE) and myel in basic protein (MBP) in the cocultured BMSCs were tested by immunofluorescent staining, and the expression of neuregul in 1 (NRG1) was detected by ELISA method. Results SCs and BMSCs were isolated and cultured successfully. The identification of SCs showed positive expression of S-100 and BMSCs showed positive expressions of CD29, CD44, and CD90. At 7 days after coculture, the BMSCs in group A began retraction, and became round or tapered with the processes and had a nerve cells or ol igodendrocytes-l ike morphology, but most BMSCs in groups B and C showed no obvious morphological changes under inverted phase contrast microscope. Immunofluorescent staining showed that the positive expression rates of NSE in groups A, B, and C were 22.39% ± 2.86%, 12.89% ± 1.78%, and 2.69% ± 0.80%, respectively, and the positive expression rates of MBP in groups A, B, and C were 16.13% ± 2.39%, 6.33% ± 1.40%, and 0.92% ± 0.17%, respectively. There were significant differences in terms of NSE and MBP positive expression rates among 3 groups (P lt; 0.05). ELISA analysis showed that NRG1 in the supernatant of group A was increased after coculture in a time-dependent manner. At 6, 9, and 12 days of coculture, NRG1 content was higher in group A than in groups B and C, and in group B than in group C, showing significant differences (P lt; 0.05). Conclusion The microenvironment formed by SCs can promote BMSCs differentiation into neurons and ol igodendrocytes, but the differentiation capabil ity of BMSCs decreases with aging, and the variety of growth factors secreted by SCs is l ikely important factors that induce the differentiation of BMSCs into neurons and ol igodendrocytes.