ABSTRACT
BACKGROUND:It wil provide a new insight into the future application of bone marrow mesenchymal stem cels in the treatment of spinal cord injury and tissue engineering by studying the effect of activation of Wnt signaling pathway in the neuronal differentiation of bone marrow mesenchymal stem cels. OBJECTIVE: To detect the expression of related genes by gene chip technology during the neuronal differentiation of bone marrow mesenchymal stem cels. METHODS:Human bone marrow mesenchymal stem cels were isolated and purified, and passage 5 cels were obtained. GatewayTM technology was used to build lentiviral vectors that was used to transfect Wnt-1 into human bone marrow mesenchymal stem cels. Control, non-transduction and transduction groups were set in this study. Human bone marrow mesenchymal stem cels were then induced to differentiate into neurons. Cel morphology was observed under inverted phase contrast microscope. Gene chip was used to detect the regulation changes and the differential expression of related genes in the Wnt signaling pathway. RESULTS AND CONCLUSION: Under the scanning electron microscope, the transfected cels were found to have the similar morphology of neuron-like cels. Analysis by the gene chip hybridization technique showed that 3 287 genes were up-regulated and 4 215 genes were down-regulated in the signal pathway. In the Wnt signaling pathway, genes related to the nervous system development and differentiation were up- or down-regulated. It is verified that the Wnt signal pathway is activated via Wnt-1 transduction, and the downstream genes appear to have genetic transcription so as to promote the neuronal differentiation of human bone marrow mesenchymal stem cels.
ABSTRACT
BACKGROUND:Bone marrow mesenchymal stem cels have low immunogenicity and can induce immune tolerance. At present, the mechanism of immune regulation of bone marrow mesenchymal stem cels is not completely understood. It has been rarely reported whether the bone marrow mesenchymal stem cels can migrate to the thymus after transplantation. OBJECTIVE:To observe the distribution and survival of bone marrow mesenchymal stem cels in the thymus of aging rats after transplantation. METHODS: Bone marrow mesenchymal stem cels cultured in vitrowere transfected by adenovirus vectors expressing green fluorescent protein. Transfected bone marrow mesenchymal stem cels were injected into the portal vein of aging rats. At days 3, 7, 14, 21 after transplantation, the survival of bone marrow mesenchymal stem cels homing to the thymus was observed under fluorescence microscope. At day 3 after transplantation, thymus tissues were taken and stained with hematoxylin-eosin for pathological observation. RESULTS AND CONCLUSION:Green fluorescent protein-labeled bone marrow mesenchymal stem cels had a strong green fluorescence at days 3 and 7 after transplantation, and the cel contour was clear. There was no significant difference in the mean absorbance values at days 3 and 7 (P> 0.05). Expression of green fluorescent protein was weakened significantly at days 14 and 21 compared with that at day 3 (P < 0.05). At 3 days after transplantation, the transplanted bone marrow mesenchymal stem cels were clearly visible in the thymus, and acute rejection was not observed. The results show that bone marrow mesenchymal stem cels can migrate to the damaged thymus tissue through the blood circulation, and can survive at least 1 week.
ABSTRACT
BACKGROUND:In recent years, many reports have focused on inflammatory cytokines, growth factors and mechanical loads affecting the cartilage and subchondral regeneration, but there is a lack of comprehensive understanding about the mechanism of osteoarthritis. OBJECTIVE: To explore the correlation between function status of bone marrow mesenchymal stem cels and disease progression in patients with osteoarthritis. METHODS:Femoral bone marrow was extracted from patients with femoral neck fractures (control group), mild (mild group) and severe (severe group) osteoarthritis to isolate and culture bone marrow mesenchymal stem cels. Cel counting kit-8 was used to detect the proliferative ability of bone marrow mesenchymal stem cels from different patient groups, and passage 3 bone marrow mesenchymal stem cels were subject to 2-week chondrogenic induction folowed by toluidine blue staining. RESULTS AND CONCLUSION: Bone marrow mesenchymal stem cels were isolated and cultured from the femoral bone marrow of different groups. The proliferative ability of cels in the control group was significantly higher than that in the mild and severe groups. After chondrogenic induction, bone marrow mesenchymal stem cels varied obviously in the morphology that was from fusiform to qusi-circular or polygon, the percentage of nucleoplasm became smaler, and cels were positive for toluidine blue staining. The number of chondrocytes generated in the severe group was less than that in the control group, but there was no great difference in cel morphology. These findings indicate that the occurrence of osteoarthritis is negatively correlated with the functional status of autologous bone marrow mesenchymal stem cels.
ABSTRACT
BACKGROUND:Gene transfer techniques have been actively used in tissue regeneration therapy. Bone morphogenetic protein 7 with osteoinductive properties can effectively promote osteoblast growth and new bone formation. OBJECTIVE:To explore the influence of bone morphogenetic protein 7 adenovirus gene transfection on the biological function of bone marrow stromal stem cels.METHODS:Goat bone marrow stromal stem cels were isolated, cultured and transfected by recombinant adenovirus containing bone morphogenetic protein 7 (Adeno-BMP7). Cel ultrastructure was observed by transmission electronic microscope, cel cycle was detected by flow cytometry, expression of bone morphogenetic protein 7 was measure by western blot assay, and Von Kossa staining was used to observe the formation of calcium nodules. Bone marrow stromal stem cels transfected for 3 days and untransfected were used to prepare coral-cel complexes that were injected subcutaneously into the back of nude mice for 4 weeks and 8 weeks, folowed by gross observation and histological examination. RESULTS AND CONCLUSION: Adeno-BMP7-transfected bone marrow stromal stem cels appeared to have active substance synthesis and metabolism. Adeno-BMP7 transfection played no effect on the cel cycle of bone marrow stromal stem cels. Bone morphogenetic protein 7 was expressed in the transfected bone marrow stromal stem cels. Larger calcium nodules were visible after Adeno-BMP7 transfection. Adeno-BMP7-transfected bone marrow stromal stem cels showed stronger osteogenic capability and higher bone quality. These results demonstrate that Adeno-BMP7 transfection can effectively promote the osteogenic differentiation of bone marrow stromal stem cels.
ABSTRACT
BACKGROUND:Stromal cel-derived factor-1 has a strong chemotaxis to bone marrow mesenchymal stem cels, and both of them can promote wound healing. However, there are less studies on their correlation with skin wound healing. OBJECTIVE:To investigate the effects of stromal cel-derived factor-1 on bone marrow mesenchymal stem cels migration and skin wound repair. METHODS: Thirty SD rats were divided into five groups at random. Bone marrow mesenchymal stem cels labeled with PKH-26 were injected into the rat caudal vein. After 1 week, skin wound models were established. Then, different concentrations (1, 2, 10, 50 μg/L) of stromal cel-derived factor-1 were injected via multi-points on the skin wound. The skin wound healing was observed and recorded at 14 days after injection. The number and distribution of bone marrow mesenchymal stem cels were observed by the fluorescent staining at different time points. The pathological changes of wound tissue were observed by hematoxylin-eosin staining. The expression of colagen I and colagen III were detected by western blot assay. RESULTS AND CONCLUSION:Stromal cel-derived factor-1 at 10 μg/L could induce the largest number of bone marrow mesenchymal stem cels to the skin wound and achieve the best repair results. Stromal cel-derived factor-1 could also regulate the expression of colagen I and colagen III in the wound, and when the concentration of stromal cel-derived factor-1 was 10 μg/L, the expressions of colagen I and colagen II reached the peak. These findings indicate that the appropriate concentration of stromal cel-derived factor-1 is better to promote the migration of bone marrow mesenchymal stem cels, thereby contributing to skin wound repair.
ABSTRACT
BACKGROUND:Human telomerase reverse transcriptase (hTERT) is the first choice for regulating the proliferation and directional differentiation, with multiple biological effects. OBJECTIVE:To observe the therapeutic effect of hTERT-transfected bone marrow mesenchymal stem cels transplantation in diabetic rats. METHODS: Bone marrow mesenchymal stem cels from Sprague-Dawley rats were culturedin vitro and transfected with retrovirus PLXSN carrying hTERT. RT-PCR was used to detect the hTERT expression in the bone marrow mesenchymal stem cels before and after transfection. Sixty male Sprague-Dawley rats were selected and equaly randomized into four groups: normal control group, transfection group, cel transplantation group, and model group. In the latter three groups, rats were injected with 45 mg/kg chain urea to establish diabetes models, and then injectedvia the tail vein with 0.2 mL hTERT-transfected bone marrow mesenchymal stem cels, 0.2 mL bone marrow mesenchymal stem cels, and 0.2 mL normal saline, respectively. RESULTS AND CONCLUSION:At 48 hours after hTERT transfection, the expression of hTERT mRNA was detected in the bone marrow mesenchymal stem cels, and mainly concentrated in the nuclei. At 14 days after transfection, the fasting glucose level in the model group was higher than that in the normal control group (P 0.05). These findings indicate that the transplantation of hTERT-transfected bone marrow mesenchymal stem cels is effective in the treatment of diabetic rats.