Abstract: Objective To transplant the microencapsulated recombinanted Chinese hamster ovary (CHO ) cells into the infracted myocardium of rodent animals and investigate whether vascular endothelial growth factor (VEGF) secreted by the implanted CHO cells could augment angiogenesis and improve cardiac function. Methods The cDNA of VEGF was transferred into CHO cells with plasmid stable transfection. After microencapsulation, the cell growth in microcapsules and the VEGF level in the culture supernatant were evaluated. Two weeks after myocardial infarction, the microencapsulated CHO cells (MC-CHO group ) were implanted into the border of infracted myocardium, as well as similar amount of CHO cells (CHO group ) , blank microcapsule (MC group ) and non-serum culture medium (control group ) as controls, 12 rats per group. The cardiac function improvement was evaluated 3 weeks after transplantation, while the survival status of implanted CHO cells, in situ secretion of VEGF and capillary density were assayed by histology. Results CHO cells could grow and proliferate after microencapsulation. The secretion of VEGF was detectable in culture media supernatant, with the highest concentration of 3 852 pg/m l at day 8. As compared to the other three groups, the left ventricular dimension and cardiac function were significantly improved in MC-CHO group 3 weeks after transplantation. The capillary density of MC-CHO group were increased significantly than those of CHO group, MC group and control group (22. 3±3. 1 vs. 15. 6±2. 8, 11. 4±2. 5, 13. 2±2. 7 vessels per 0.13 mm2, P lt; 0.05). The implanted microcapsule maintained its original shape and protected theCHO cells in it. Conclusion M icroencapsulaed recombinanted CHO cells transplantation might be a promising app roach to augment angiogenesis and improve the cardiac function in infarction myocardium.
Abstract: Objective To investigate the effect of autologous bone marrow mesenchymal stem cells (MSCs) transplantation on cardiac function and their proliferation and differentiation in the post-infarct myocardium in rabbits. Methods Twenty New Zealand rabbits were randomly divided into two groups, the autologous bone marrow mesenchymal stem cells group (MSCs group,n=10) and control group (n=10). Myocardial infarct model was set up by ligation of the left anterior descending (LAD), two weeks after establishment of the infarct model,either 400μl of cell suspension (total cells 1×106) labled by 1,1’-dioctadecyl3,3,3’,3’-tetramethyl indocarbocyanine perchlorate (Dil) or a comparable volume of L-DMEM medium were autologously transplanted into several different points of the periphery of the scar respectively. To evaluate the heart function, echocardiography were performed before modeling,two weeks after modeling, 2 and 4 weeks after the cells transplantation for asurements of left ventricular end systolic diameter (LVESD) and left ventricular end diastolic diameter (LVEDD), tocalculate left ventricular eject fraction(LVEF) and left ventricular fractional shortening (LVFS). Meanwhile the myocardial contrast echocardiography (MCE) were performed for evaluating the blood perfusion of the post-infarct myocardium. Eight weeks after the transplantation, the animalswere undergoing euthanasia, specimens were acquired for pathology. Results Echocardiography indicated that:The LVEF and LVFS between two groups were fundamentally the same before modeling,two weeks after modeling respectively (0.72±0.08 vs. 0.71±0.04,0.56±0.11 vs. 0.55±0.09; 0.35±0.06 vs. 0.35±0.04, 0.24±0.08 vs. 0.23±0.03, Pgt;0.05), but those were improved significantly in group MSCs when compared with control group at two weeks and four weeks after the cells transplantation(0.71±0.05 vs. 0.60±0.05，0.72±0.07 vs. 0.62±0.08 and 0.34±0.03 vs. 0.29±0.01， 0.35±0.06 vs. 0.27±0.05 respectively,Plt;0.05). There were no differences in LVESD and LVEDD between two groups in any time points(Pgt;0.05). MCE showed the blood perfusion of the infarct myocardium were improved two and four weeks after the cell transplantation. Pathology indicated that Dil positive cells were survived in MSCs transplanted hearts, stained positively for αsarcomeric actin and desmin eight weeks after cell transplantation, HE slides indicated that the capillary density in all the cells transplanted hearts were much higher when compared with control group (38.6±7.6/mm2 vs. 21.4±3.9/mm2，Plt;0.05). ConclusionMSCs can differentiate into cardiomyocytes, improve myocardial perfusion and cardiac function when transplanted into ischemic myocardium.
Objective To investigate the effects of chondroitinase ABC (ChABC) combined with bone marrow mesenchymal stem cells (BMSCs) in repair spinal cord injury of rats. Methods Primary BMSCs were isolated and cultured from the femur and tibia of neonatal Sprague Dawley (SD) rats. The spinal cord injury model was established in 24 adult SD male rats (weighing, 200-230 g), which were randomly divided into control group (group A), BMSCs transplantation group (group B), ChABC injection group (group C), and ChABC and BMSCs transplantation group (group D), 6 rats in each group. At 7 and 14 days after injury, Basso-Beattie-Bresnahan (BBB) score criteria was used to evaluate the hindlimb motor function; at 14 days after injury, the injured spinal cord tissue was perfused and stained by HE for further calculation of the injury area. Immunofluorescence staining were used for observing the expressions of glial fibrillary acidic protein (GFAP)/chondroitin sulfate proteoglycan (CSPG) and GFAP/growth associated protein 43 (GAP43). Results At 7 days after injury, three joints movement of the hindlimbs were recovered in all groups, and no significant difference in the BBB score was found among 4 groups (P gt; 0.05). At 14 days after injury, no load drag was observed in 3 joints of the hindlimbs in groups A, B, and C, but weight-bearing plantar or occasional dorsalis pedis weight-bearing walking was observed in group D with no plantar walking. The BBB score of group D was significantly higher than that of the other 3 groups (P lt; 0.05). HE staining showed that the cavity formed in the damage zone, and there were a large number of macrophages in the cavity and its surrounding, which was wrapped by scar tissue. The damage area of group D was significantly smaller than that of the other 3 groups (P lt; 0.05). At 14 days after injury, the GFAP/CSPG double immunofluorescence staining showed that the astroglial scar damage zone in group D was significantly reduced, and no cavity formation was found. And the fluorescence intensity in groups C and D was significantly lower than that in group B (P lt; 0.05). The GFAP/GAP43 double immunofluorescence staining showed that GAP43-positive fibers passed through the damage zone in group D and the fluorescence intensity in group D was significantly higher than those in groups B and C (P lt; 0.05). Conclusion Inhibition of astrocytes secreting CSPG by ChABC combined with BMSCs transplantation in early injury may promote the regeneration of nerve fibers, and repair spinal cord injury in rats.
Objective To investigate the effect of the serum from severe burn patients on the biology characteristics of human umbilical cord mesenchymal stem cells (hUCMSCs) in vitro, so as to explore the feasibility of hUCMSCs transplantation for treating severe burn. Methods The 3rd passage of hUCMSCs were randomly divided into 3 groups: 10% fetal bovine serum group (group A), 10% normal serum group (group B), and 10% burn serum group (group C). At 24 hours, 72 hours, and 6 days after culture, the cell morphology and density were observed by inverted microscope; the cell proliferation was assessed by MTT; after 6 days of culture, the cell cycle by propidium iodide staining and flow cytometry, the apoptosis by acridine orange/ethidium bromide staining, and the cell senescence by β-galactosidase staining; the levels of tumor necrosis factor α (TNF-α), interleukin 1 (IL-1), platelet-derived growth factor (PDGF), and insulin-like growth factor 1 (IGF-1) in serum were detected by a double-antibody sandwich ELISA kit. Results hUCMSCs were long spindle/polygon in 3 groups. The cell fusion of group C was obviously faster than that in group A and group B. The cell proliferation curves showed that the velocity and number of cell proliferation in group C were significantly higher than those in group A and group B at 2-6 days after culture (P lt; 0.05). The rates of proliferation period (S) of hUCMSCs were 9.21% ± 1.02%, 11.79% ± 1.87%, and 20.54% ± 2.03%, respectively in groups A, B, and C at 6 days, and group C was significantly higher than that of group A and group B (P lt; 0.05). The hUCMSCs showed normal morphology and structure in 3 groups, and no apoptosis cells was observed. The positive cells percentage of group C (2.6% ± 0.1%) was significantly lower than that of group A (4.8% ± 0.2%) and group B (3.8% ± 0.4%) (P lt; 0.05). The levels of TNF-α, IL-1, PDGF, and IGF-1 in group C were significantly higher than those in group B (P lt; 0.05). Conclusion The higher levels of cytokines in serum from the severe burn patients can significantly stimulate hUCMSCs proliferation, prevent cells apoptosis, and reduce cells senescence. Therefore, it is feasible to use hUCMSCs transplantation for treating severe burn patients.
Objective To summarize the recent progress of cell-based approaches for promoting bone regeneration in distraction osteogenesis (DO). Methods Recent literature concerning enhancement of bone regeneration following DO using cell-based approaches was reviewed and analyzed. Results An overview of 4 different cell-based approaches was mainly provided: single cell injection, cell scaffold-based strategies/injectable tissue engineered bone, microtissue technology or cell aggregate technology, and stem cell gene therapy. Each has its advantages and disadvantages. Other methods are still in the experimental research except that compound injection of bone marrow mesechymal stem cells and platelet-rich plasma has been applied to clinical practice. Conclusion The cell-based approach is a promising strategy in the field of bone regenerative medicine. These approaches have bright future in promoting bone regeneration and reducing the treatment period in DO in the clinical application. However, well-designed preclinical studies are required to establish safe and effective guidelines for cell-based approaches to promoting bone regeneration during DO.
Objective To introduce the basic research and cl inical potential of the hair foll icle stem cells related signal transduction in prol iferation and differentiation. Methods The recent original articles about the hair foll icle stem cells were extensively reviewed. Results Many different signal pathways had been involved in the skin development and self-newals.The hair foll icle stem cells could play an important role in the skin self-renewal and regeneration which were modulated by several different signal pathways, which included bone morphogenetic protein/transforming growth factor β, Wnt, Notch and ectodysplasin A genes. Conclusion The hair foll icle stem cells may be a future approach to repair cutaneous wounds as a cell therapy．
Objective To evaluate the transfection efficiency and expression level of hepatocyte growth factor (HGF) by transfecting a recombinant adenovirus carrying HGF gene (Ad-HGF) into bone marrow mesenchymal stem cells (BMSCs) and to explore the effect of the expression supernatant on BMSCs in vitro so as to lay a foundation for the manufacture of gene medicine which expresses efficient cell factors. Methods Rat BMSCs were isolated using Percoll density gradient method and cultured according to the adherent property of BMSCs. The expression of c-Met was detected by immunohistochemical examination. BMSCs were infected with a recombinant adenovirus carrying green fluorescent protein gene (Ad-GFP) at multipl icity of infection (MOI, 0, 25, 50, 100, and 200 pfu/cell). To select an optimal MOI, the transfection efficiency and the degree of cell damage were assayed by flow cytometry and MTT, respectively, at 48 hours after transfecting. The expression of HGF in BMSCs transfected with optimal MOI Ad-HGF was measured with ELISA assay. MTT method was used to evaluate the prol iferation effect of HGF expression supernatant on BMSCs. Results Immunohistochemical staining showed that BMSCs expressed c-Met receptor for HGF. At 48 hours after transfecting with different MOI Ad-GFP (0, 25, 50, 100, and 200 pfu/cell), the transfection efficiencies were 0.34% ± 0.04%, 40.72% ± 0.81%, 61.72% ± 1.04%, 85.33% ± 0.83%, and 17.91% ± 0.63%, respectively; and the highest transfection efficiency was observed at 100 pfu/cell MOI. The cell damage was obviously observed when MOI was 200 pfu/cell. The expression of HGF in BMSCs reached the highest level after being transfected with 100 pfu/cell MOI Ad-HGF for 48 hours. The expression product could stimulate the prol iferation of BMSCs. The prol iferation of BMSCs gradually rose with the increase of HGF protein, and reached the highest level at 10% (320 pg). Conclusion BMSCs can be transfected efficiently with Ad-HGF and express HGF protein, which stimulates the prol iferation of BMSCs. It suggests that BMSCs is an ideal repair cells with gene vector.
【Abstract】 Objective To review the recent progress of cell therapy in cl inical appl ications. Methods Therecent l iterature about cell therapy in cl inical appl ications was extensively reviewed. Results Based on the advances in cell biology, especially the rapid progress in stem cell biology, an increasing number of cl inical trials about cell therapy for management of various diseases, such as cardiovascular system diseases, neural system diseases, musculo-skeletal diseases, diabetes, stress urinary incontinence, and others, had been reported with encouraging results. All these showed that cell therapy had great potentials in cl inical appl ication. Conclusion Cell therapy provides a novel approach for the treatment of many human diseases. However, the mechanism remains to be fully elucidated.
Objective To review and summarize the latest development of the therapy for the Duchenne muscular dystrophy (DMD). Methods Therecentlypublished articles related to the therapies for DMD were extensively reviewed and briefly summarized. Results The therapeutic approaches for DMD included the gene therapy, the cell therapy, and the pharmacological therapy. The gene therapy and the cell therapy were focused on the treatment for the cause of DMD by the delivery of the missing gene, the modification of the mutated gene, and the transfer of the normal cells including the stem cells, while the pharmacological therapy dealt with the downstream events caused by the dystrophin gene defect, slowed down the pathologic progress of DMD, and improved the DMD patient’s life quality and life span, by medication and other factor treatments. Conclusion There is still no cure for DMD because of various difficulties in replacing or repairing thedefected gene and of the multifaceted nature of the severe symptoms. Therefore,it is imperative for us to find out a more effective treatment that can solve these problems.
Objective To review the advance in the experimental studies and evaluate the potential therapeutic application of the mesenchymal stem cells(MSCs). Methods The related articles published in China and theother countries during the recent years were extensively reviewed and analyzed. Results The MSCs were widely used in the cell-transplantation therapy and the tissue engineering because of their pluripotency of differentiation into various kinds of cells. They were also frequently used in the gene therapy because they could stably express the transfected objective genes. Because of their immunomodulatory function, the MSCs could also be used in the immunotherapy. Conclusion The MSCs are the stem cells, which have characteristics of renewing themselves, having multipotency, and being easy to undergo amplification in vitro.The MSCs are ideal target cells for the cell therapy, tissue engineering, gene therapy, and immunotherapy.