Abstract： Objective To investigate the effects of hepatocyte growth factor（HGF）gene transfected bone marrow mesenchymal stem cells （MSCs）transplantation in pigs with chronic ischemic heart disease. Methods MSCs were isolated from pig bone marrow by density gradient centrifugation and adherent cell culture, purified, and determined by cellsurface antigens（CD34, CD44, CD71, Ⅷ factor and desmin）. MSCs were transfected by adenovirus expressing hepatocyte growth factor（AdHGF）, and the influence of HGF on the biological characteristics of MSCs was tested. The pig model of chronic myocardial ischemia was established by placing Ameroid ring inside the left circumflex coronary artery via leftthoracotomy. A total of 40 pigs were randomly divided into 5 groups （n=8） and were injected 5×106/ml MSCs＋ 4×109 pfu 200 μl AdHGF （MSCs＋ AdHGF group）, 4×109 pfu 200 μl AdHGF （AdHGF group）, 5×106/ml MSCs 200 μl（MSCs group），4×109 pfu 200 μl AdNull （AdNull group）and 1 ml saline（control group） into the ischemic myocardiumrespectively. Echocardiogram, digital subtraction angiography （DSA） of coronary artery, single photon emission computed tomography（SPECT） myocardial perfusion imaging and cardiomyocyte apoptosis were examined after 4 weeks. Results Positive CD44 and CD71 and negative CD34, Ⅷ factorand desmin were detected in MSCs by flow cytometer. HGF had a b influence on stimulating the proliferation and differentiation of MSCs. Echocardiogram examination showed that left ventricular end-diastolic volume（LVEDV），left ventricular ejection fraction（LVEF），fractional shortening（FS）of MSCs＋ AdHGF group were significantly increased after treatment （P＜ 0.05）. DSA detection showed that ischemic neovascularization of MSCs＋ AdHGF group was significantly higher than those of AdHGF group and MSCs group （P＜ 0.05）. SPECT showed that the left ventricular myocardium of MSCs＋ AdHGF group appeared thickened,myocardial perfusion was significantly improved and the myocardial motion was significantly increased （P＜ 0.05）. Vascular density of MSCs＋ AdHGF group was significantly higher than those of AdHGF group and MSCs group by HE stain of myocardium ［（39.4±1.2）/ HPF vs. （36.5±1.4）/ HPF and（34.5±1.7）/ HPF，P＜ 0.05］. Cardiomyocyte apoptosis rate of MSCs＋ AdHGF group was significantly lower than those of AdHGF group and MSCs group by TUNEL stain （P＜ 0.05）. Conclusion Combination transplantation can promote the angiogenesis of chronic ischemic myocardium, inhibit cardiomyocyte apoptosis and improve heart function in pigs with chronic ischemic heart disease. The effect of HGF gene transfected MSCs transplantation is better than that of MSCs or HGF transplantation alone.
ObjectiveTo investigate the co-transplantation of C57-green fluorescent protein (GFP) mouse epidermis and dermis cells subcutaneously to induce the hair follicle regeneration.
MethodC57-GFP mouse epidermis and dermis were harvested for isolation the mouse epidermis and dermis cells. The morphology of epidermis and dermis mixed cells at ratio of 1:1 of adult mouse, dermis cells of adult mouse, cultured 3rd generation dermis cells were observed by fluorescence microscope. Immunocytochemistry staining was used to detect hair follicle stem cells markers in cultured 3rd generation dermis cells from new born C57-GFP mouse. And then the epidermis and dermis mixed cells of adult mouse (group A), dermis cells of adult mouse (group B), cultured 3rd generation dermis cells of new born mouse (group C), and saline (group D) were transplanted subcutaneously into Balb/c nude mice. The skin surface of nude mice were observed at 4, 5, 6 weeks of transplantation and hair follicle formation were detected at 6 weeks by immunohistochemistry staining.
ResultsThe isolated C57-GFP mouse epidermis and dermis cells strongly expressed the GFP under the fluorescence microscope. Immunocytochemistry staining for hair follicle stem cells markers in cultured 3rd generation dermis cells showed strong expression of Vimentin and α-smooth muscle actin, indicating that the cells were dermal sheath cells; some cells expressed CD133, Versican, and cytokeratin 15. After transplanted for 4-6 weeks, the skin became black at the injection site in group A, indicating new hair follicle formation. However, no color change was observed in groups B, C, and D. Immunohistochemical staining showed that new complete hair follicles structures formed in group A. GFP expression could be only observed in the hair follicle dermal sheath and outer root sheath in group B, and it could also be observed in the hair follicle dermal sheath, outer root sheath, dermal papilla cells, and sweat gland in group C. The expression of GFP was negative in group D.
ConclusionsCo-transplantation of mouse epidermis and dermis cells can induce the hair follicle regeneration by means of interaction of each other. And transplantation of isolated dermis cells or cultured dermis cells individually only partly involved in the hair follicles formation.
Objective To investigate the cl inical effect of MSCs transplantation derived from human umbil ical cord on bone nonunion. Methods From December 2005 to December 2007, 72 patients with traumatic bone nonunion were treated. Auto-il iac bone transplantation was used in 36 patients (group A), including 27 males and 9 females, aging (34.0 ± 2.1) years; including 18 cases of femoral fracture and 18 cases of tibia fracture; and the time of bone nonunion being (9.1 ± 1.7)months. Percutaneous MSCs transplantation derived from human umbil ical cord was used in 36 patients (group B), including 28 males and 8 females, aging (36.0 ± 1.6) years; including 18 cases of femoral fracture and 18 cases of tibia fracture; and the time of bone nonunion being (6.4 ± 1.9) months. There were no statistically significant differences in general data between two groups (P gt; 0.05). In group A, the site of bone nonunion was filled with relevant auto-il iac bone. In group B, the mixture of 6-8 mL platelet-rich plasma prepared by centrifugal izing venous blood and 1 × (106-107) P5 MSCs extracted from human umbil ical cord denoted by volunteers was injected into the region of bone nonunion with 0.2 g demineral ized bone powder. Results Incision healed by first intention in group A. No puncture, deep infection, rejection and general fever reaction occurred in group B. All patients in two groups were followed up for (13.2 ± 4.6) months. No loosening and breakage of internal fixation were observed in two groups. The motil ity and function of hip, knee and ankle were good. The time of bone union was (10.3 ± 2.8) months in group A and (5.6 ± 0.8) months in groups B, showing significant difference between two groups (P lt; 0.05). Conclusion The percutaneous MSCs transplantation derived from human umbil ical cord is more effective on bone nonunion than the traditional treatment, it is easily-to-operate, safe, rel iable, and rapid for union. It is one of effective methods in treating bone nonunion.
The capacity for self-regeneration of the adult heart is very limited, conventional therapies cannot solve the loss of cardiomyocytes in the infarcted heart leads to continuous ventricular remodeling. Cell transplantation therapy is emerging as a novel approach for myocardial repair over conventional therapies. Various types of cell transplantation have improved cardiac function and angiogenesis in animal models and clinical settings. The safety and feasibility of some clinical trials have been initiated. In this review, we summarize the advantages and limitations of different cell types proposed for cell transplantation in myocardial infarction and give an overview of the clinical trials using this novel therapeutic approach in patients with myocardial infarction.
Objective To introduce the research of nucleus pulposus cells for treating intervertebral disc degeneration. Methods The original articles in recent years about nucleus pulposus cells for treating intervertebral disc degeneration were extensively reviewed, and retrospective and comprehensive analysis was performed. Results Nucleus pulposus cells are not only simply a remnant of embryonic notochordal cells, but have also an important influence on the well-being of the whole disc. The biological treatment strategies aim to regenerate the disc by either trying to improve the micro-enviroment within the disc or to increase the popoulation of the nucleus pulposus, which includes transplanting mesenchymal stem cellsto differentiate into nucleus-l ike cells in the degenerated intervertebral disc. Conclusion Nucleus pulposus cells or ucleus pulposus l ike cells based cell transplantation methods prove to be a promising and real istic approach for the intervertebral disc regeneration.
Objective To investigate the expression of micro-dystrophin gene in myoblast cultured in vitro, to explore the possibil ity of combining myoblast transplantation with gene transfer for Duchenne muscular dystrophy therapy. Methods Competent Escherichia coli JM109 was prepared, which transformed with plasmid pSL139, and positive clones were picked to cultivate. Plasmid was extracted with Alkal ine lysis method and cutted with both Pvu I and Cla I enzyme. Agarose gel electrophoresis was employed to take pictures. Ten healthy 5-7 days old male C57/BL10 mice were selected, weighing4-5 g, the primary and subcultured myoblasts were cultured with multi-step enzymatic digestion and differential adhesionmethod, and Desmin immunofluorescent method was used to identfy. The 3rd generation myoblasts that were transfected with plasmid pSL139 mediated by l iposome served as the experimental group, untransfected cells served as the control group. After 48 hours of transfection, the expressions of micro-dystrophin mRNA and protein in myoblasts were detected with RTPCR and cell immunofluorescent methods, and the transfection efficiency was caculated. Results After pSL139 plasmids being digested and for 40 minutes agarose gel of electrophoresis, 3.75 kb fragment of target gene and vector were observed. The cells were almost uniform, and triangular or diamond shape after 24-48 hours of culture; the cells turned to fusion manner and could be passaged after 4-6 days. Desmin immunofluorescent result showed that green fluorescence was seen in cytoplasm of most 2nd myoblasts, and the purity of the myoblasts was above 90%. At 48 hours after transfection of myoblasts with plasmid pSL139, RT- PCR results showed that about 300 bp fragment was seen in the experimental group and the control group, and the brightness was higher in experimental group. Immunofluorescent staining displayed that green fluorescence was seen in the cytoplasm of the myoblasts in the experimental group and no green fluorescence in the control group; the expression efficiency of positive cells for micro-dystrophin was 45%-55% in experimental group. Conclusion Micro-dystrophin gene can highly express at the levels of mRNA and protein respectively in myoblasts transfected with plasmid pSL139 mediated by l iposome.
Based on the pathogenic mechanisms of age-related macular degeneration (AMD), tremendous preclinical and clinical trials have demonstrated that cell transplantation which aim to replace impaired retinal pigment epithelium (RPE) with healthy RPE cells is a promising approach to treat AMD. So far, choices of cell sources mainly are autologous RPE, iris pigment epithelium, fetal RPE, human embryonic stem cell-derived RPE and human induced pluripotent stem cell-derived RPE, and some of them are undergoing clinical researches. Grafting manners in cell-based therapies are various including RPE sheet or RPE-choroid complex transplantation, RPE cell suspension injection, and RPE sheet transplantation with scaffolds. This review is limited to cell-based therapies for RPE that damaged first in the progress of AMD and focus on recent advances in cell sources, transplantation methods, preclinical and clinical trials, and the obstacles that must be overcome.
Objective
To summarize the research situation of stem cells transplantation for intervertebral disc (IVD) degeneration.
Methods
The original articles about stem cells transplantation for repair of IVD degeneration were extensively reviewed; the clinical applications, the mechanisms, and related factors to influence repair effect were analyzed; and obstacles in stem cells transplantation for repair of IVD degeneration.
Results
Autogenic stem cells transplantation can repair IVD degeneration and effectively relieve the symptoms of low back and leg pain. Stem cells can differentiate into disc chondrocytes in the disc microenvironment, increase the production of various growth factors, and exert a trophic effect on disc cells. It is also evident that the transplanted stem cells can potentially protect disc cells from apoptosis and maintain an immune-privileged state in the IVD. Multiple factors such as tissue origin of stem cells, methods to pre-modulate the seeds, choice of injectable scaffolds, and even the severity of degeneration are closely related to the repair effects. To get a more efficient stem cell therapy, future researches are challenged to modulate the migration and distribution of stem cells in the IVD, avoid flow back, and better understand their ability to restore stemness properties within the degenerative disc niche.
Conclusion
Stem cells transplantation is proven to be a promising biological approach for repair of IVD degeneration.
Objective To investigate the effect of bone marrow mesenchymal stem cells (BMSCs) transplantation on the motor function recovery, the expression of vascular endothel ial growth factor (VEGF) gene, and angiogenesis after spinal cord injury (SCI) in rats, and to explore the treatment mechanism of BMSCs in SCI. Methods BMSCs were isolated and cultured from the marrow of 5 Wistar rats (4 weeks old) and the 3rd-4th passage cells were prepared for the experiment. Atotal of 87 adult female Wistar rats (weighing 220-250 g) were randomly divided into 3 groups: sham-operated group (group A, n=21), DMEM group (group B, n=33), BMSCs group (group C, n=33). A laminectomy was only performed at T8-10 levels in group A. The SCI models were establ ished by modified Nystrom’s compression method in groups B and C, and BMSCs and DMEM were injected in groups B and C respectively at 30 minutes after SCI. Basso-Beattie-Bresnahan (BBB) score was used for the motor function recovery at 3, 7, 14, and 28 days, RT-PCR for the VEGF mRNA at 1, 3, and 5 days, and immunohistochemical staining for angiogenesis at 3, 7, 14, and 28 days. Results In groups B and C, the hindl imb locomotor function was improved at different degrees with time, showing significant difference in BBB score between groups B, C and group A (P lt; 0.05). At 28 days, the BBB score in group C was significantly higher than that in group B (P lt; 0.05) and there was no significant difference between groups B and C (P gt; 0.05) at 3, 7, and 14 days after transplantation. The numbers of microvessels in the ventral horns of gray matter around SCI in groups B and C were significantly lower than that in group C (P lt; 0.05) at 3 days, but there was no significant difference at 7, 14, and 28 days after transplantation (P gt; 0.05). There was no significant difference in the number of microvessels between group C and group B (P gt; 0.05) at 3 and 7 days, but the number of microvessels in group C was significantly higher than that in group B (P lt; 0.05) at 14 and 28 days after transplantation. However, there was no significant difference in the number of microvessels in the white matter around SCI in 3 groups at different time points after transplantation (P gt; 0.05). The RT-PCR results showed that VEGF mRNA expressed at a low level in group A. Compared with group A, the expression level of VEGF mRNA in groups B and C increased at 1 day and reached the peak at 3 days, then decreased at 5 days after transplantation; and the expression of VEGF mRNA was significantly higher in groups B and C than in group A (P lt; 0.05),and in group C than in group B (P lt; 0.05) at 1, 3, and 5 days. Conclusion BMSCs may promote the motor function recoveryby up-regulating VEGF mRNA expression and increasing angiogenesis in the spinal cord after SCI in rats.
Objective To compare single cell suspension of neural stem cells (NSCs) with neurospheres transplantation for spinal cord injury (SCI) so as to explore the therapeutic effectiveness of two NSCs transplantation methods for SCI. Methods The NSCs were isolated from the spinal cord of adult Sprague Dawley (SD) rats, purified and cultured. At passage 3, the cells were identified by Hoechst33342, Nestin staining, and gl ial fibrillary acidic protein staining for differentiated cells. Sixty adult SD rats (weighing 230-250 g) were made the SCI models at T10 level with modified Allen method and randomlydivided into 3 groups (20 rats in each). The injury sites were treated by injecting 5 μL sal ine (group A), 5 μL single cellssuspensions of NSCs at passage 3 (group B), and 5 μL neurospheres cell suspensions at passage 3 (group C). At preoperation and 3, 7, 14, 21, and 28 days after operation, the locomotor functions of each group were assessed using the Basso, Beattie, and Bresnahan (BBB) rating scale. HE staining was applied to observe the morphology of spinal cord. Subsequently immunofluorescence staining was used to observe microtubule-associated protein 2 (MAP-2). Results The cells cultured were NSCs by morphological observation and immunofluorescence staining. After 3 days of modeling surgery, BBB score significantly decreased when compared with preoperative score, and there was no significant difference among 3 groups at 3 and 7 days (P gt; 0.05). BBB score increased in different degrees with time; at 14, 21, and 28 days, BBB score of groups B and C was better than that of group A, and group C was better than group B, showing significant differences (P lt; 0.05). HE staining showed that spinal cord structure of group C was more clear than that of groups A and B, and had less scar. There was no significant difference in the number of MAP-2 positive cells among 3 groups at 3 and 7 days (P gt; 0.05). At 14, 21, and 28 days, the number of MAP-2 positive cells of groups B and C was significantly more than that of group A, and group C was more than group B, showing significant differences (P lt; 0.05). Conclusion Transplantation of neurospheres suspension compared with single cell can significantly promote NSCsto differentiate into neurons and is conducive to recover the lower extremity function after SCI.
