Objective To construct lentiviral vector carrying the human hepatocyte growth factor (hHGF) gene, and then to get hHGF gene/modified bone marrow mesenchymal stem cells (BMSCs) by infecting the BMSCs. Methods The hHGF gene was obtained with PCR from pcDNA-hHGF plasmid. The recombination lentiviral vector plasmid hHGF was constructed with Age I digestion and gene recombinant, then was identified with PCR and sequencing. Mediated by Lipofectamine2000, the three plasmids system of lentiviral vector including pGC-E1-hHGF, pHelper 1.0, and pHelper 2.0 was co-transfected to 293T cells to produce hHGF gene. The supernatant was collected and concentrated by ultracentrifugation and the titer of lentivirus was measured by real-time quantitative PCR. The BMSCs were infected by the constructed lentivirus and the multipl icities of infection (MOI) was identified with fluorescent microscope, the efficiency of infection with flow cytometry (FCM) analysis, the hHGF level with ELISA analysis, and the expression of hHGF gene with RT-PCR. Results Lentiviral vector carrying hHGF gene was constructed successfully. The titer of lentivirus was 1 × 108 TU/mL. The infection efficiency of BMSCs by hHGF lentiviral was high and reached 98% by FCM, and the best MOI was 10. A great mount of green fluorescence was observed with the fluorescent microscope at 28 days after infection. Peak concentration of hHGF secreted by BMSCs/hHGF reached 40.5 ng/mL at 5 days. The concentration could maintain a high level until 28 days after infection. RT-PCR showed that BMSCs/hHGF could express hHGF gene. Conclusion By lentiviral vector, hHGF gene was integrated into BMSCs genome, and it can express stably.
ObjectiveTo explore the effect and mechanisms of bone marrow mesenchymal stem cells (BMSCs) on healing quality of acetic acid-induced gastric ulcer.
MethodsForty-eight clean grade male Wistar rats were used to establish the model of gastric ulcer with acetic acid and were randomly divided into 3 groups after 3 days of modeling, 16 rats each group. After the abdominal cavity was open and stomach was pulled out, no treatment was given in group A, 150 μL phosphate buffered saline (PBS) and 150 μL BMSCs at passage 4+PBS (1×108 cells/100 μL) were injected into the gastric wall surrounding the ulcer at 5 different points in groups B and C respectively. After 10 days, the ulcer area was measured, the mucosal thickness and the number of dilated glands were tested in the regenerative mucosa by histological method. And the expression of vascular endothelial growth factor (VEGF) was detected at ulcerative margin by immunohistochemical method.
ResultsThe ulcer area in group C was significantly smaller than that of groups A and B (P<0.01), but no significant difference was found between groups A and B (P>0.05). HE staining showed that group C had thicker regenerative gastric mucosa, less dilated glands, and more regular mucosal structure than groups A and B, showing significant differences in regenerative gastric mucosa thickness and dilated glands number (P<0.01), but no significant difference between groups A and B (P>0.05). Immunohistochemical staining showed that the positive expression of VEGF in the ulcer margin mucosa of group C was significantly higher than that of groups A and B. The integral absorbance (IA) value of VEGF expression in group C was significantly higher than that in groups A and B (P<0.01), but no significant difference between groups A and B (P>0.05).
ConclusionBMSCs can accelerate ulcer healing by the secretion of VEGF, and improve the quality of ulcer healing.
ObjectiveTo investigate the effect of echinococcus granulosus protoscolices on the differentiation of bone marrow mesenchymal stem cells (BMSCs) into fibroblasts.MethodsFemur bone marrow of 4-week-old C57BL/6 mice was taken and BMSCs were isolated and cultured by adherent culture. Echinococcus granulosus protoscolices was extracted from the liver of sheep infected with echinococcus granulosus. The experiment was divided into two groups. The experimental group was co-cultured with the 3rd generation BMSCs and the echinococcus granulosus protoscolices, and the control group was the 3rd generation BMSCs. Before and after co-culture, the morphology of BMSCs and the activity of echinococcus granulosus protoscolices were observed by inverted microscope. After cultured for 1, 3, 5, and 7 days, the mRNA expressions of transforming growth factor β1 (TGF-β1), collagen type Ⅰ, and collagen type Ⅲ were detected by real-time fluorescent quantitative PCR, the protein expressions of TGF-β1, collagen type Ⅰ, collagen type Ⅲ, Smad7, and phosphorylated Smad2/3 were detected by Western blot, and the contents of collagen type Ⅰ and collagen type Ⅲ in the supernatant of the two groups were detected by ELISA.ResultsAfter 7 days of co-culture, the morphology of BMSCs changed into fusiform and irregular triangle, which was closer to the mouse fibroblasts. The relative mRNA expressions of TGF-β1, collagen type Ⅰ, and collagen type Ⅲ in the experimental group were significantly higher than those in the control group; the relative protein expressions of TGF-β1, collagen type Ⅰ, collagen type Ⅲ, and phosphorylated Smad2/3 in the experimental group were significantly higher than those in the control group, and the relative protein expression of Smad7 in the experimental group was significantly lower than that in the control group; the contents of collagen type Ⅰ and collagen type Ⅲ in the supernatant of the experimental group were significantly higher than those in the control group. The differences between the two groups were significant (P<0.05).ConclusionEchinococcus granulosus protoscolices may promote the secretion of collagen type Ⅰ, collagen type Ⅲ, and TGF-β1 by TGF-β1/Smad signal pathway, which can promote the fibrosis of BMSCs that related to the formation of fibrocystic wall by echinococcosis.
Objective
To explore the paracrine effect of bone marrow mesenchymal stem cells (BMSCs) on dexamethasone-induced inhibition of osteoblast function in vitro.
Methods
The serum free conditioned medium of mouse BMSCs cultured for 24 hours was prepared for spare use. The 3rd passage of MC3T3-E1 cells were divided into 4 groups: the control group (group A), dexamethasone group (group B), dexamethasone+BMSCs conditioned medium (1:1) group (group C), and BMSCs conditioned medium group (group D). After 24 hours of culture, the alkaline phosphatase (ALP) content was determined; the protein expressions of RUNX2 and Osteocalcin were detected by Western blot; and the gene expressions of collagen type I-α 1 (COL1A1), RUNX2, ALP, and Osteocalcin were detected by real-time fluorescence quantitative PCR (RT-qPCR); alizarin red staining was used to observe calcium nodules formation at 21 days.
Results
After cultured for 24 hours, ALP content was significantly lower in groups B, C, and D than group A, and in group B than groups C and D (P < 0.05), but no significant difference was found between groups C and D (P > 0.05). The relative protein expression of RUNX2 of group B was significantly lower than that of groups A, C, and D (P < 0.05), but difference was not significant between groups A, C, and D (P > 0.05). The relative protein expression of Osteocalcin was significantly lower in group B than groups A, C, and D, in groups A and C than group D (P < 0.05), but difference had no significance between groups A and C (P > 0.05). The relative gene expressions of RUNX2, Osteocalcin, COL1A1, and ALP of groups B, C, and D were significantly lower than those of group A (P < 0.05); the relative gene expressions of RUNX2, Osteocalcin, and ALP were significantly higher in group D than groups B and C, in group C than group B (P < 0.05). The gene expression of COL1A1 was significantly higher in group D than group B (P < 0.05), but difference was not significant between groups B and C, and between groups C and D (P > 0.05). The cells of group A all died at 6 days after culture; at 21 days, the calcium no dule staining was positive by alizarin red in groups B, C and D, and the degree of the staining gradually increased from groups B to D.
Conclusion
BMSCs conditioned medium can alleviate the inhibitory effect of dexamethasone on osteoblasts function.
ObjectiveTo investigate the effect of overexpressing the Indianhedgehog (IHH) gene on the chondrogenic differentiation of rabbit bone marrow mesenchymal stem cells (BMSCs) in a simulated microgravity environment.
MethodsThe 2nd generation BMSCs from rabbit were divided into 2 groups: the rotary cell culture system (RCCS) group and conventional group. Each group was further divided into the IHH gene transfection group (RCCS 1 group and conventional 1 group), green fluorescent protein transfection group (RCCS 2 group and conventional 2 group), and blank control group (RCCS 3 group and conventional 3 group). RCCS group cells were induced to differentiate into chondrocytes under simulated microgravity environment; the conventional group cells were given routine culture and chondrogenic induction in 6 well plates. During differentiation induction, the ELISA method was used to detect IHH protein expression and alkaline phosphatase (ALP) activity, and quantitative real-time PCR to detect cartilage and cartilage hypertrophy related gene expressions, and Western blot to detect collagen typeⅡ, agreecan (ANCN) protein expression; and methylene blue staining and Annexin V-cy3 immunofluorescence staining were used to observe cell slide.
ResultsAfter transfection, obvious green fluorescence was observed in BMSCs under fluorescence microscopy in RCCS groups 1 and 2, the transfection efficiency was about 95%. The IHH protein levels of RCCS 1 group and conventional 1 group were significantly higher than those of RCCS 2, 3 groups and conventional 2, 3 groups (P < 0.05); at each time point, ALP activity of conventional 1 group was significantly higher than that of conventional 2, 3 groups (P < 0.05); ALP activity of RCCS 1 group was significantly higher than that of RCCS 2 and 3 groups only at 3 and 7 days (P < 0.05). Conventional 1 group expressed high levels of cartilage-related genes, such as collagen typeⅡand ANCN at the early stage of differentiation induction, and expressed high levels of cartilage hypertrophy-related genes, such as collagen type X, ALP, and Annexin V at the late stage (P < 0.05). RCCS 1 group expressed high levels of cartilage-related genes and low levels of cartilage hypertrophy-related genes at all stages. The expression of collagen typeⅡprotein in conventional 1 group was significantly lower than that of conventional 2 and 3 groups at 21 days after induction (P < 0.05); RCCS 1 group expressed high levels of collagen typeⅡand ANCN proteins at all stages (P < 0.05). Methylene blue staining indicated conventional 1 group was stained lighter than conventional 2 and 3 groups at 21 days after induction; while at each time point RCCS 1 group was significantly deeper than RCCS 2 and 3 groups. Annexin V-cy3 immunofluorescence staining indicated the red fluorescence of conventional 1 group was stronger than that of conventional 2 and 3 groups at each time point. The expression of red fluorescence in each RCCS subgroup was weak and there was no significant difference between the subgroups.
ConclusionUnder the simulated microgravity environment, transfection of IHH gene into BMSCs can effectively promote the generation of cartilage and inhibit cartilage aging and osteogenesis. Therefore, this technique is suitable for cartilage tissue engineering.
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.
Objective To transplant intravenously human brain-derived neurotrophic factor (hBDNF) genemodified bone marrow mesenchymal stem cells (BMSCs) marked with enhanced green fluorescent protein (EGFP) to injured spinal cord of adult rats, then to observe the viabil ity of the cells and the expressions of the gene in spinal cord, as well as theinfluence of neurological morphological repairing and functional reconstruction. Methods Ninety-six male SD rats weighing (250 ± 20) g were randomly divided into 4 groups: hBDNF-EGFP-BMSCs transplantation group (group A, n=24), Ad5-EGFPBMSCs transplantation group (group B, n=24), control group (group C, n=24), and sham operation group (group D, n=24). In groups A, B, and C, the spinal cord injury models were prepared according to the modified Allen method at the level of T10 segment, and after 3 days, 1 mL hBDNF-EGFP-BMSCs suspension, 1 mL Ad5-EGFP-BMSCs suspension and 1 mL 0.1 mol/L phosphate buffered sal ine (PBS) were injected into tail vein, respectively; in group D, the spinal cord was exposed without injury and injection. At 24 hours after injury and 1, 3, 5 weeks after intravenous transplantation, the structure and neurological function of rats were evaluated by the Basso-Beattie-Bresnahan (BBB) score, cortical somatosensory evoked potential (CSEP) and transmission electron microscope. The viabil ity and distribution of BMSCs in the spinal cord were observed by fluorescent inverted phase contrast microscope and the level of hBDNF protein expression in the spinal cord was observed and analyzed with Western blot. Meanwhile, the expressions of neurofilament 200 (NF-200) and synaptophysin I was analyzed with immunohi stochemistry. Results After intravenous transplantation, the neurological function was significantly improved in group A. The BBB scores and CSEP in group A were significantly higher than those in groups B and C (P lt; 0.05) at 3 and 5 weeks. The green fluorescence expressions were observed at the site of injured spinal cord in groups A and B at 1, 3, and 5 weeks. The hBDNF proteinexpression was detected after 1, 3, and 5 weeks of intravenous transplantation in group A, while it could not be detected in groups B, C, and D by Western blot. The expressions of NF-200 and synaptophysin I were ber and ber with transplanting time in groups A, B, and C. The expressions of NF-200 and synaptophysin I were best at 5 weeks, and the expressions in group A were ber than those in groups B and C (P lt; 0.05). And the expressions of NF-200 in groups A, B, and C were significantly ber than those in group D (P lt; 0.05), whereas the expressions of synaptophysin I in groups A, B, and C were significantly weaker than those in group D (P lt; 0.05). Ultramicrostructure of spinal cords in group A was almost normal. Conclusion Transplanted hBDNF-EGFP-BMSCs can survive and assemble at the injured area of spinal cord, and express hBDNF. Intravenous implantation of hBDNF-EGFP-BMSCs could promote the restoration of injured spinal cord and improve neurological functions.
ObjectiveTo compare the osteogenic effect of bone marrow mesenchymal stem cells (BMSCs) transfected by adenovirus-bone morphogenetic protein 2-internal ribosome entry site-hypoxia inducible factor 1αmu (Ad-BMP-2-IRES-HIF-1αmu) and by Ad-cytomegalovirus (CMV)-BMP-2-IRES-human renilla reniformis green fluorescent protein 1 (hrGFP-1) single gene so as to optimize the source of osteoblasts. MethodsBMSCs were separated and cultured from 1-month-old New Zealand white rabbit. The BMSCs at passage 3 were transfected by virus. The experiment was divided into 4 groups (groups A, B, C, and D) according to different virus: BMSCs were transfected by Ad-BMP-2-IRES-HIF-1αmu in group A, by Ad-CMV-BMP-2-IRES-hrGFP-1 in group B, by Ad-CMV-IRES-hrGFP-1 in group C, and BMSCs were not transfected in group D. The optimum multiplicity of infection (MOI) (50, 100, 150, and 200) was calculated and then the cells were transfected by the optimum MOI, respectively. The expression of BMP-2 gene was detected by immunohistochemistry staining after transfected, the expressions of BMP-2 protein and HIF-1α protein were detected by Western blot method. The osteogenic differentiation potential was detected by alkaline phosphatase (ALP) activity and Alizarin red staining. ResultsThe optimum MOI of groups A, B, and C was 200, 150, and 100, respectively. The expression of BMP-2 was positive in groups A and B, and was negative in groups C and D by immunohistochemistry staining; the number of positive cells in group A was more than that in group B (P ﹤ 0.05). The expression of BMP-2 protein in groups A and B was significantly higher than that in groups C and D (P ﹤ 0.05), group A was higher than group B (P ﹤ 0.05). The expression of HIF-1α protein in group A was significantly higher than those in the other 3 groups (P ﹤ 0.05), no significant difference was found among the other 3 groups (P ﹥ 0.05). ALP activity in groups A and B was significantly higher than that in groups C and D (P ﹤ 0.05), group A was higher than group B (P ﹤ 0.05). Calcium nodules could be seen in groups A and B, but not in groups C and D; the number of calcium nodules in group A was higher than that in group B (P ﹤ 0.05). ConclusionThe expression of BMP-2 and osteogenic effect of BMSCs transfected by Ad-BMP-2-IRES-HIF-1αmu (double genes in single carrier) are higher than those of BMSCs transfected by Ad-CMV-BMP-2-IRES-hrGFP-1 (one gene in single carrier).
Objective To explore the effects of bone marrow mesenchymal stem cells (BMSCs) transfected with adenovirus hepatocyte growth factor (Ad-HGF) on wound repair in diabetic rats. Methods BMSCs from male Wistar rats were isolated by density gradient centrifugation, cultured, and transfected with Ad-HGF. The multi pl icity of infection was 100. Diabetic models were establ ished in 20 female Wistar rats by diets in high fat and sugar plus intraperitoneal injection ofstreptozotocin (30 mg/kg). Then 2 full-thickness skin wounds (approximately 1.5 cm in diameter) were made on the dorsum. The rats were randomly divided into 4 groups (n=5 rats). After wounding, the 0.3 mL suspensions of BMSCs (group A), Ad- HGF (group B), BMSCs transfected with Ad-HGF (group C), and PBS (group D) were injected directly into the derma of wounds. The transverse diameter and longitudinal diameter of wound were measured at 21 days after treatment. At 7 days and 28 days after treatment, HE staining was performed to evaluate wound heal ing. The contents of hydroxyprol ine and advanced glycosylation end products (AGEs) in the wounds were measured by enzyme l inked immunosorbent assay and fluorospectrophotometer, respectively, at 3, 7, 14, and 28 days after treatment. Results At 21 days after treatment, the wounds almost healed in group C, and the transverse diameter and longitudinal diameter were 0 and (0.110 ± 0.024) cm, respectively. But the wounds healed partially in groups A, B, and D, and the transverse diameter and longitudinal diameter were (0.470 ± 0.051) cm and (0.590 ± 0.041) cm, (0.390 ± 0.042) cm and (0.480 ± 0.032) cm, and (0.700 ± 0.068) cm and (0.820 ± 0.068) cm, respectively. There were significant differences in wound heal ing between group C and groups A, B, and D (P lt; 0.05). The wound heal ing time of group C [(20.5 ± 1.9) days] was significantly shorter (P lt; 0.05) than those of groups A, B, and D [(28.3 ± 1.9), (25.9 ± 2.3), and (36.6 ± 5.1) days]. At 7 days, the HE staining showed that evident epidermis transportation, collagen formation, and leukocytes infiltration were observed in group C. At 28 days, the HE staining showed that the epidermis in group C was significantly thinner and more regular than those in other groups, and the decreased collagen and many small vessels were observed in group C. The content of hydroxyprol ine in group C was higher than those in groups A, B, and D at 7 days and 14 days (P lt; 0.05). The contents of AGEs in group C was lower than those in groups A, B, and D at 14 days and 28 days (P lt; 0.05). Conclusion Transplantation of BMSCs transfected with Ad-HGF can accelerate the wounds repair in diabetic rats.
【Abstract】 Objective To review the progress in the treatment of spinal cord injury (SCI) by graft of neuralstem cells (NSCs) or bone marrow mesenchymal stem cells (BMSCs) as well as immune characteristics of two stemcells. Methods Different kinds of documents were widely collected, and then immunologic characteristics of NSCs andBMSCs were summarized. The therapy of SCI by stem cell transplantation was reviewed. Additionally, some problems intreatment were analyzed. Results Experimental study showed that graft of NSCs and BMSCs can promote the functionalrecovery of the injured spinal cord in animals. Due to immunologic properties of two stem cells, rejection reaction oftransplantation could produce a harmful effect on SCI treatment. Conclusion Transplantation of NSCs or BMSCs might bean effective measure for SCI treatment, but immunologic rejection reaction must be considered.
