Morphological, electrophysiological and coupling characteristics of bone marrow-derived mononuclear cells-an in vitro-model.

OBJECTIVE: Transplantation of bone marrow-derived mononuclear cells (BMC) may be suitable to prevent myocardial remodeling and improve left ventricular function after myocardial infarction. However, it is unknown whether or not cardiomyocytes and BMCs can form functioning cell-to-cell coupling and develop adequate electrophysiological properties. METHODS: BMCs were isolated from minipig leg bones, treated with 5-azacytidine (10 microM) for 24 h, cultured for 7 days and labeled with a fluoroscopic dye (DIL). BMCs were cocultured with spontaneously beating cardiomyocytes of neonatal rats. On days 4, 7 and 14 cocultured cells were analyzed. Immunhistochemistry (Connexin 43, alpha-actinin) was used to assess cardiomyogenic differentiation. Action potential characteristics were recorded in whole cell patch clamp mode and to investigate intercellular communication a second gap junction permeable fluoroscopic dye was brought into BMCs by microinjection (Lucifer yellow, LY). RESULTS: From day 7 in coculture BMCs beated synchronously with neonatal rat cardiomyocytes. On day 14, 55.9% of BMCs expressed alpha-actinin and 98.3% were positive for gap junction protein connexin 43. BMC action potential duration (APD90) was mean 11.1 ms with dV/dt(max) of 26.8 V/s and similar to atrial cardiac type. However, microinjection of LY revealed only little dye transfer into adjacent rat cardiomyocytes. CONCLUSIONS: Cocultured BMCs have the potential for early expression of muscle specific proteins in about 60% after 14 days and for cardiac gap junction proteins. Synchronous beating indicates an effective electromechanical coupling. In this heterologous setting we could prove only weak metabolic coupling.     

Can a bone marrow cell contribute to organ regeneration? In vivo analysis using transgenic rats with reporter genes

Although implantation of multipotent bone marrow-derived stem cells represents an attractive new cell therapy to repair damaged tissues, recent reports have raised serious concerns over the feasibility of using stem cells deriving from the bone marrow to promote cell transdifferentiation. We established transgenic (Tg) rats with reporter genes as specific molecular tags to examine the effect of bone marrow cells (BMCs) on transdifferentiation into tissues/organs. To monitor transdifferentiation events of locally transplanted BMCs into hepatocytes or capillary endothelial cells, a liver injury model and an ischemic hind-limb model were developed in rats. To test the ability of circulating bone marrow-derived cells to give rise to myocytes after skeletal muscle injury, we used a bone marrow cell transplantation model from Tg rats, which showed ubiquitous expression of beta-galactosidase (lacZ), into lethally irradiated non-Tg rats. Our results show that there was little transdifferentiation of BMCs into the targeted cells in these tissue injury models. However, in the ischemic hind-limb model, laser Doppler imaging and histologic analysis showed that both implantation of BMCs and treatment with microspheres incorporating basic fibroblast-like growth factor (bFGF), which enables the release of bFGF at the site of action over a period of time, effectively induced angiogenesis. In conclusion, rat BMCs with specific marker genes could be a useful tool for detecting transdifferentiation events in vivo.     

Development of a spontaneously beating vein by cardiomyocyte transplantation in the wall of the inferior vena cava in a rat: a pilot study

PURPOSE: This study was conducted to determine whether it is feasible to develop a vein that rhythmically beats by implanting immature cardiomyocytes in its wall. METHODS: Neonatal cardiomyocytes (5 x 10(6) cells each) were transplanted into the wall of the inferior vena cava in six female Fischer rats; in six rats, only the medium was transplanted. At 3 weeks after transplantation, the grafted site of the inferior vena cava was exposed and videotaped, and then processed for histology. RESULTS: Distinct rhythmic beating of the vena cava at the site of cell injection (at a rate lower than aortic beating) was observed in all six rats treated with neonatal cardiomyocyte injections, but in none of the six that received the medium. The vena cava continued to beat spontaneously and rhythmically after the aortas were clamped and after the heart was excised. The beating was manifest by visual contraction and relaxation of the vessel wall. The spontaneous beating rate was 101 +/- 7 beats/min at 1 to 3 minutes after excision of the heart. Hematoxylin and eosin staining showed viable grafts in the wall of the vena cava in all that were implanted with neonatal cardiac cells; but in none of the vena cava that received the medium. Neonatal cardiomyocytes in the graft matured with cross striations and stained positive for the muscle marker sarcomeric actin. CONCLUSIONS: The present study demonstrates that neonatal cardiomyocytes survive, mature, and spontaneously and rhythmically contract when implanted in the wall of a vein.     

Bone Marrow-Derived Stem Cells Attenuate Impaired Contractility and Enhance Capillary Density in a Rabbit Model of Doxorubicin-Induced Failing Hearts

Abstract   Background: There is a regenerative potential of bone marrow-derived stem cells (BMCs) in ischemic cardiomyopathy, but little is known of their effects in nonischemic cardiomyopathy. This study evaluates the effects of BMC transplantation on contractility and remote capillary density of doxorubicin-induced failing hearts. Methods: Heart failure was induced in rabbits by doxorubicin (3 mg/kg; 6 weeks), followed by BMC transplantation (BMC group, 1.5–2.0 × 10⁶ cells, n = 15), sham treatment (Medium group, n = 10), or no therapy (Dox group, n = 6). Healthy rabbits were used as controls (n = 10). Cells were transplanted locally into the left ventricle (LV). Four weeks later, contractility was assessed. Cross-sections of hearts were investigated by H&E, Picrosirius red stain, and immunohistologically (Troponin I, α-Actinin, Connexin43). Capillary density (CD31-antigen) was examined in the LV, septum, and right ventricle (RV). Results: Global contractility was significantly higher in the BMC group versus Medium group (ejection fraction: 39.0 ± 1.4% vs. 30.0 ± 1.9%, p = 0.002, and fractional shortening: 22 ± 0.8 vs. 19 ± 0.6, p < 0.01). Hemodynamic measurements by Millar catheter (Millar Instruments, Houston, TX, USA) were also significantly improved. Capillary density increased in cell-treated hearts (LV: 55 ± 2.2 vs. 42 ± 2.0, p < 0.001, RV: 40 ± 2.1 vs. 35 ± 1.7, p = 0.065, and septum: 46 ± 1.5 vs. 39 ± 1.7, p = 0.005), when compared to the Medium group. The transplanted cells failed to express cardiac markers. The collagen content was reduced in BMC-treated rabbits. Conclusion: Despite local cell transplantation, autologous BMCs improve global contractility and enhance remote capillary density and collagen content in doxorubicin-induced cardiomyopathy. However, BMCs failed to transdifferentiate into new cardiomyocytes.     

DiI荧光示踪剂在大鼠脾内肝细胞移植中的研究

目的 探讨大鼠肝细胞在脾内移植后的生存、迁移及其并发症情况。方法 先用ＤｉＩ荧光示踪剂标记肝细胞再行脾内肝细胞移植。在不同时间段取肝、脾、肺、心、肾 、胸腺组织冷冻切片,在荧光显微镜下用荧光和普通光示踪观察。结果 ＤｉＩ荧光示踪剂能很好地标记肝细胞,６０ｄ实验期内,移植细胞能在所取各器官中生存并保持良好形态,未发现有区域梗塞灶、同时还反映了其在肝实质中的分布。结论 ＤｉＩ是一种新颖、使用简便的荧光     

Small-diameter blood vessels engineered with bone marrow-derived cells

OBJECTIVE: The objective of this study is to investigate if bone marrow-derived cells (BMCs) regenerate vascular tissues and improve patency in tissue-engineered small-diameter (internal diameter = 3 mm) vascular grafts. SUMMARY BACKGROUND DATA: BMCs have demonstrated the ability to differentiate into endothelial-like cells and vascular smooth muscle-like cells and may offer an alternative cell source for vascular tissue engineering. Thus, we tissue-engineered small-diameter vascular grafts with BMCs and decellularized arteries. METHODS: Canine BMCs were differentiated in vitro into smooth muscle alpha-actin/smooth muscle myosin heavy-chain-positive cells and von Willebrand factor/CD31-positive cells and seeded onto decellularized canine carotid arteries (internal diameter = 3 mm). The seeded grafts were implanted in cell donor dogs. The vascular-tissue regeneration and graft patency were investigated with immunohistochemistry and angiography, respectively. RESULTS: The vascular grafts seeded with BMCs remained patent for up to 8 weeks in the canine carotid artery interposition model, whereas nonseeded grafts occluded within 2 weeks. Within 8 weeks after implantation, the vascular grafts showed regeneration of the 3 elements of artery (endothelium, media, and adventitia). BMCs labeled with a fluorescent dye prior to implantation were detected in the retrieved vascular grafts, indicating that the BMCs participated in the vascular tissue regeneration. CONCLUSIONS: Here we show that BMCs have the potential to regenerate vascular tissues and improve patency in tissue-engineered small-diameter vascular grafts. This is the first report of a small-diameter neovessel engineered with BMCs as a cell source.     

血管内皮生长因子C在人乳腺癌细胞株MCF-7及MCF-7/Adr中的表达

目的：检测血管内皮生长因子C（vascular endothelial growth factor C,VEGF-C)mRNA和蛋白在人乳腺癌细胞株MCF－7及其耐药株MCF－7／Adr中的定位，定性表达。方法：根据VEGF－C基因序列，设计合成地高辛标记的特异性寡核苷酸探针，运用原位杂交方法检测培养的细胞株MCF－7和MCF－7／Adr中VEGF－C mRNA的表达；并运用免疫组织化学方法检测了两种细胞中VEGF－C蛋白的表达。结果：原位杂交检测到MCF－7和MCF－7／Adr细胞的胞浆中有阳性蓝色颗粒，免疫组化检测发现两种细胞的胞浆中均有阳性棕黄色颗粒，而阴性对照细胞的胞浆中则均无阳性颗粒。结论：人乳腺癌细胞株MCF－7及其耐药株MCF－7／Adr细胞能够转录VEGF－C mRNA并在其细胞浆中翻译合成相应的蛋白。     

Danshen‐Enhanced Cardioprotective Effect of Cardioplegia on Ischemia Reperfusion Injury in a Human‐Induced Pluripotent Stem Cell‐Derived Cardiomyocytes Model

Myocardial ischemia‐reperfusion (I/R) injury is unavoidable during cardioplegic arrest and open‐heart surgery. Danshen is one of the most popular traditional herbal medicines in China, which has entered the Food and Drug Administration‐approved phase III clinical trial. This study was aimed to develop a human‐induced pluripotent stem cell‐derived cardiomyocytes (hiPSC‐CMs) model to mimic I/R injury and evaluate the cardioprotective effect of regular cardioplegic solution with Danshen. hiPSC‐CMs were cultured with the crystalloid cardioplegic solution (Thomas group) and Thomas solution with 2 or 10 µg/mL Danshen (Thomas plus Danshen groups). The cells under normoxic culture condition served as baseline group. Then, the cells were placed in a modular incubator chamber. After 45 min hypoxia and 3 h reoxygenation, hiPSC‐CMs subjected to hypoxia/reoxygenation resulted in a sharp increase of reactive oxygen species (ROS) content in Thomas group versus baseline group. Compared with the Thomas group, ROS accumulation was significant suppressed in Thomas plus Danshen groups, which might result from elevating the content of glutathione and enhanced activities of superoxide dismutase and glutathione peroxidase. The enhanced L‐type Ca²⁺ current in hiPSC‐CMs after I/R injury was also significantly decreased by Danshen, and meanwhile intracellular Ca²⁺ level was reduced and calcium overload was suppressed. Thomas plus Danshen groups also presented less irregular transients and lower apoptosis rates. As a result, Danshen could improve antioxidant and calcium handling in cardiomyocytes during I/R and lead to reduced arrhythmia events and apoptosis rates. hiPSC‐CMs model offered a platform for the future translational study of the cardioplegia.     

Purified human bone marrow multipotent mesenchymal stem cells regenerate infarcted myocardium in experimental rats

Recent findings suggest the feasibility of cardiac repair by transplantation of bone marrow mesenchymal stem cell (MSCs). However, it remains controversial regarding which cell type is the best source for transplanting into the ischemic heart because of lack of well-defined cell markers. In this study, we investigated the in vitro and in vivo effects of the novel multipotent marrow mesenchymal stem cells (MMSCs) from human bone marrow. Pluripotent markers (Oct4, Bmi1, and Abcg2) and vascular endothelial growth factor (VEGF) were detected by RT-PCR and immunofluorescence in MMSCs. Myocardial differentiation was induced in the expanded MMSC cultures by treatment with 5-azacyline. Expressions of VEGF in the animals transplanted with MMSCs were markedly increased in comparison with the animals injected with fibroblasts or saline at both mRNA and protein levels. VEGF expression was observed in both transplanted MMSCs and recipient cardiomyocytes by immunofluorescence. Confocal immunofluorescence microscopy revealed the specific markers for cardiomyocytes and endothelial cells in transplanted MMSCs 14 days after transplantation. Vessel count was increased and left ventricular function improved post-MMSC transplantation. These results indicate that transplantation of purified MMSCs from human bone marrow upregulated VEGF expression, enhanced angiogenesis, and improved the functional recovery following myocardial infarction in rats.     

Serum‐independent Cardiomyogenic Transdifferentiation in Human Endometrium‐derived Mesenchymal Cells

Media with high concentrations of serum are commonly used to induce cardiomyogenic transdifferentiation in mesenchymal stem cells; however, serum contains numerous unknown growth factors and interferes with definition of specific cardiomyogenic transdifferentiation factors secreted from feeder cells. In the present study, we determined whether the transdifferentiation of human mesenchymal cells can be observed in a FBS‐free medium. The efficiency of transdifferentiation was observed in 10% FBS‐containing standard medium (10%FBS) and in FBS‐free medium containing insulin and thyroxin (FBS‐free). In the present study, we used human uterine endometrium‐derived mesenchymal cells (EMC100, EMC214) and menstrual blood‐derived mesenchymal cells (MMCs). After cardiomyogenic transdifferentiation, the efficiency and physiological properties of cardiomyogenesis (fractional shortening of the cell [%FS] and action potential [AP]) were evaluated. The efficiency of transdifferentiation in EMC100 and in MMCs increased 36%* and 163%* (*P < 0.05), respectively. The %FS in EMCs increased to 103%*. AP‐duration more than 250 ms with a marked plateau was only observed in FBS‐free (3/19), and not in 10% FBS (0/41). The cardiomyogenic transdifferentiation of human mesenchymal cells can be observed in the FBS‐free medium. Phenotypes of generated cardiomyocytes were significantly more physiological in FBS‐free than in 10% FBS.     

Endogenous bone-marrow-derived stem cells contribute only a small proportion of regenerated myocardium in the acute infarction model.

BACKGROUND: Our recent study showed that granulocyte-colony stimulating factor (G-CSF) promoted bone-marrow cells (BMC) to migrate into the infarcted heart and that they differentiated into cardiomyocytes. However, we still do not know to what degree bone-marrow-derived cardiomyocytes contribute to myocardial regeneration after injury. In this study, we verified the proportional contribution of cells from bone marrow (BM) and from non-bone marrow (n-BM) in regenerating neomyocardium after myocardial infarction. METHODS: Eight C57BL/6 mice were irradiated (900 cGy), and green fluorescent protein (GFP) mouse-derived BMCs (GFP-BMC, 1 x 10(6) cells) were injected. Four weeks later, the left descending coronary artery was ligated. Recombinant human G-CSF (200 microg/kg/day, 8 days) was injected. At 4 weeks after ligation, hearts were fixed for histology. We calculated the proportions of cardiomyocytes derived from BM and n-BM after taking the chimeric rate into consideration. RESULTS: The chimeric rate was 54.6% +/- 5.9%. At the infarcted border area, the total cell number was 1000.3 +/- 56.5/mm(2), and mobilized BM-derived GFP-BMC was 103.3 +/- 13.1/mm(2). After compensation with the chimeric rate, we found BM-derived troponin I-positive cells at 23.9 +/- 4.1/mm(2), nestin-positive cells at 12.9 +/- 2.6/mm(2), and Ki67-positive cells at 18.3 +/- 2.6/mm(2), respectively. We found significant differences in the contribution of troponin I-(6.7% +/- 1.7% vs 93.3% +/- 1.7%), nestin- (2.4 +/- 0.5 vs 97.6 +/- 0.5), and Ki67-positive (3.9 +/- 1.0 vs 96.1 +/- 1.0) cells derived from BM and n-BM. CONCLUSIONS: Bone marrow was one of the origins of regenerated cardiomyocytes; however, the contribution of cells from BM was very small compared with those of n-BM origin in the infarction model.     

The fate of transplanted xenogeneic bone marrow‐derived stem cells in rat intervertebral discs

Intervertebral disc degeneration is a major cause and a risk factor for chronic low back pain. The potential of using stem cells to treat disc degeneration has been raised. The aims of our study were to assess whether xenogeneic bone‐marrow derived stem cells could survive in a rat disc degeneration model and to determine which cell types, if any, survived and differentiated into disc‐like cells. Human bone‐marrow derived CD34⁺ (hematopoietic progenitor cells) and CD34^? (nonhematopoietic progenitor cells, including mesenchymal stem cells) cells were isolated, fluorescent‐labeled, and injected into rat coccygeal discs. The rats were sacrificed at day 1, 10, 21, and 42. Treated discs were examined by histological and immunostaining techniques and compared to control discs. The survival of transplanted cells was further confirmed with a human nuclear specific marker. Fluorescent labeled CD34^? cells were detected until day 42 in the nucleus pulposus of the injected discs. After 3 weeks these cells had differentiated into cells expressing chondrocytic phenotype (Collagen II and Sox‐9). In contrast, the fluorescent labeled CD34⁺ cells could not be detected after day 21. No fluorescence‐positive cells were detected in the noninjected control discs. Further, no inflammatory cells infiltrated the nucleus pulposus, even though these animals had not received immunosuppressive treatment. Our data provide evidence that transplanted human BM CD34^? cells survived and differentiated within the relative immune privileged nucleus pulposus of intervertebral disc degeneration. © 2008 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 27:374–379, 2009     

Albumin-Producing Hepatocytes Derived from Cryopreserved F344 Rat Bone Marrow Cells Transplanted in the Livers of Congenic Nagase's Analbuminemic Rats

Purpose Hematopoietic stem cells (SCs) are thought to have the potential to differentiate into hepatocytes; however, this potential has not been reported for cryopreserved SCs. We investigated whether cryopreserved bone marrow cells (BMCs) from F344 rats (F344) can induce the growth of albumin-producing hepatocytes in the livers of congenic Nagase's analbuminemic rats (F344alb). Methods F344 BMCs were cryopreserved in University of Wisconsin (UW) solution containing 10% fetal bovine serum and 12% dimethylsulfoxide, at −80°C. After thawing, 20 × 10⁶ cells were infused via the portal vein into the livers of F344alb immediately after 70% hepatectomy (PH). We examined the recipient livers for albumin-positive (alb+) hepatocytes and albumin mRNA, and measured the serum albumin levels 4 weeks later. Results Single and double alb+ hepatocytes were occasionally seen in the F344alb livers without the BMC transplantation. However, clusters consisting of more than three alb+ hepatocytes were seen in the livers of recipients transplanted with the cryopreserved BMCs after PH, the same as in the livers transplanted with freshly isolated BMCs. Normal albumin mRNA was detected in the recipient livers and the serum albumin levels were increased. Conclusion Cryopreserved F344 BMCs can induce the growth of alb+ hepatocytes after transplantion in the F344alb liver after PH.     

Significant improvement of heart function by cotransplantation of human mesenchymal stem cells and fetal cardiomyocytes in postinfarcted pigs

BACKGROUND: Viable cardiomyocytes after myocardial infarction (MI) are unable to repair the necrotic myocardium due to their limited capability of regeneration. The present study investigated whether intramyocardial transplantation of human mesenchymal stem cells (hMSCs) or cotransplantation of hMSCs plus human fetal cardiomyocytes (hFCs; 1:1) reconstituted impaired myocardium and improved cardiac function in MI pigs. METHODS AND RESULTS: Cultured hMSCs were transfected with green fluorescent protein (GFP). Six weeks after MI induction and cell transplantation, cardiac function was significantly improved in MI pigs transplanted with hMSCs alone. However, the improvement was even markedly greater in MI pigs cotransplanted with hMSCs plus hFCs. Histological examination demonstrated that transplantation of hMSCs alone or hMSCs plus hFCs formed GFP-positive engrafts in infarcted myocardium. In addition, immunostaining for cardiac alpha-myosin heavy chain and troponin I showed positive stains in infarcted regions transplanted with hMSCs alone or hMSCs plus hFCs. CONCLUSIONS: Our data demonstrate that transplantation of hMSCs alone improved cardiac function in MI pigs with a markedly greater improvement from cotransplantation of hMSCs plus hFCs. This improvement might result from myocardial regeneration and angiogenesis in injured hearts by engrafted cells.     

人骨髓来源多能成体祖细胞与人肝细胞系体外间接共培养向肝样细胞分化的实验研究

目的探索人骨髓来源多能成体祖细胞ZHJ-MAPCs与人肝细胞系L02在体外间接共培养条件下诱导其横向分化为肝细胞的可行性，为其在组织工程学研究和临床医学中的应用奠定基础。方法将分别接种于盖玻片上的ZHJ-MAPCs和人肝细胞系L02共置于直径10cm培养皿中实现间接共培养。于间接共培养第1、3、5、7天免疫细胞化学鉴定ZHJ-MABCs的ALB、AFP、CK-18、CK-19等肝细胞特征性表型表达变化情况，并设阳性对照（单独培养的L02细胞）和阴性对照（单独培养未经诱导的ZHJ-MAPCs），计数阳性细胞比率。结果AFP在ZHJ-MAPCs间接共培养第1天即表现为强阳性。ALB在共培养第3天出现较强的阳性，第5天达到高峰。CK-18在培养第5天开始出现阳性。CK-19在各时间点均为阴性着色。阳性对照细胞ALB及CK18有较强的阳性表达，AFP弱阳性表达，CK19阴性表达。阴性对照细胞均为阴性表达。结论与人肝细胞系L02间接共培养能够诱导人骨髓来源的ZHJ-MAPCs向成熟肝样细胞横向分化。     

瘦素对人肾小管上皮细胞表型转化及纤维连接蛋白表达的影响

目的:通过观察瘦素(leptin)刺激对人肾小管上皮细胞(HK-2)表型转化和纤维连接蛋白(FN)表达的影响,探讨瘦素对HK-2细胞转分化的作用。方法:将体外培养的HK-2细胞分为对照组和不同浓度瘦素作用组。倒置显微镜下观察HK-2细胞形态学变化;实时荧光定量RT-PCR法检测HK-2细胞α-平滑肌肌动蛋白(α-smooth muscle actin,α-SMA)、E-钙黏蛋白(E-cadherin)和FN mRNA的表达水平;免疫细胞化学法检测HK-2细胞表达α-SMA的阳性细胞百分数;酶联免疫吸附法(ELISA)检测HK-2细胞培养液上清中FN的表达。结果:分别用50、100、200 ng/ml瘦素作用HK-2细胞48 h后,(1)HK-2细胞逐渐由椭圆形变成长梭形,类似肌成纤维细胞的形态;(2)RT-PCR结果表明,瘦素作用可以下调E-cadherin mRNA的表达,同时上调α-SMA、FN mRNA的表达。(3)免疫细胞化学结果表明,对照组HK-2细胞几乎不表达α-SMA,随着瘦素作用浓度的增加,α-SMA阳性的HK-2细胞百分数逐渐增多;(4)ELISA结果表明,对照组HK-2细胞有基础水平的FN分泌,各瘦素作用组上清液中FN的表达水平较对照组显著增加,且呈一定的剂量依赖关系。结论:瘦素可诱导肾小管上皮细胞转分化为肌成纤维细胞,分泌细胞外基质,从而可能参与肾间质纤维化的发生发展。     

Artificial matrix helps neonatal cardiomyocytes restore injured myocardium in rats

The purpose of this study was to investigate whether an artificial matrix can help neonatal cardiomyocytes restore an injured heart in a rat model of myocardial infarction (MI). The left coronary arteries of female Sprague Dawley (SD) rats were ligated to create MI models. Ventricular cardiomyocytes from 1- to 3-day-old SD rats (both sexes) were isolated, cultured, and labeled. Three weeks after MI, the animals were randomized into four groups: (i) group cell plus matrix (n = 12); (ii) group cell (n = 12); (iii) group matrix (n = 12); and (iv) group control (n = 11). Four weeks after transplantation, echocardiography and the Langerdoff model were used to assess heart function. Immunohistochemical staining and polymerase chain reaction (PCR) were performed to track the implanted cardiomyocytes and detect the sex-determining region Y gene on the Y chromosome. Histology study and PCR showed that transplanted cardiomyocytes survived, formed condensed tissue, and produced connected protein in group cell plus matrix. Heart function assessment indicated transplantation of cardiomyocytes plus matrix preserved left ventricle wall thickness, fraction shortening, and end-systolic internal diameter most effectively.     

静脉注射后脂肪来源干细胞在创伤大鼠体内的迁移

目的 研究静脉注射后的脂肪来源干细胞向大鼠创伤部位的迁移和聚集情况.方法 取SD大鼠6只,制备1.8 cm×1.8 cm范围的皮肤全层及0.5 cm深度的皮下软组织缺损的创伤模型.取2.4×10~6个SD大鼠第3代脂肪来源干细胞经DiI标记后通过尾静脉注射到创伤大鼠体内,分别于移植后24、48 d分批处死大鼠,获得各时间点的创面愈合组织及健康组织标本,冰冻切片后荧光显微镜下观察荧光分布,同时组织石蜡包埋后行切片、HE染色.结果 与健康皮肤组织比较,24 d时在创面愈合组织周边和皮下组织深层部位可见较强的荧光分布,48 d时结合组织病理学观察可以发现在真皮层、腺样结构组织内荧光较强.结论 创伤可定向诱导大鼠脂肪来源干细胞在体内的迁移和集聚.