Objective Tissue engineered bone (TEB) lacks of an effective and feasible method of storage and transportation. To evaluate the activity of osteogenesis and capabil ity of ectopic osteogenesis for TEB after freeze-dried treatment in vitro and in vivo and to explore a new method of preserving and transporting TEB. Methods Human bone marrow mesenchymal stem cells (hBMSCs) and decalcified bone matrix (DBM) were harvested from bone marrow and bone tissue of the healthy donators. TEB was fabricated with the 3rd passage hBMSCs and DBM, and they were frozen and dried at extremely low temperatures after 3, 5, 7, 9, 12, and 15 days of culture in vitro to obtain freeze-dried tissue engineered bone (FTEB). TEB and FTEB were observed by gross view and scanning electron microscope (SEM). Western blot was used to detect the changes of relative osteogenic cytokines, including bone morphogenetic protein 2 (BMP-2), transforming growth factor β1 (TGF-β1), and insul in-l ike growth factor 1 (IGF-1) between TEB and FTEB. The ectopic osteogenesis was evaluated by the methods of X-ray, CT score, and HE staining after TEB and FTEB were transplanted into hypodermatic space in athymic mouse. Results SEM showed that the cells had normal shape in TEB, and secretion of extracellular matrix increased with culture time; in FTEB, seeding cells were killed by the freeze-dried process, and considerable extracellular matrix were formed in the pore of DBM scaffold. The osteogenic cytokines (BMP-2, TGF-β1, and IGF-1) in TEB were not decreased after freeze-dried procedure, showing no significant difference between TEB and FTEB (P gt; 0.05) except TGF-β1 15 days after culture (P lt; 0.05). The ectopic osteogenesis was observed in TEB and FTEB groups 8 and 12 weeks after transplantation, there was no significant difference in the calcified level of grafts between TEB and FTEB groups by the analysis of X-ray and CT score. On the contrary, there was no ectopic osteogenesis in group DBM 12 weeks after operation. HE staining showed that DBM scaffold degraded and disappeared 12 weeks after operation. Conclusion The osteogenic activity of TEB and FTEB is similar, which provides a new strategy to preserve and transport TEB.
ObjectiveTo investigate the effectiveness of human placental decidua basalis derived mesenchymal stem cells (PDB-MSCs) in repairing full-thickness skin defect of nude mice. MethodsHuman placenta samples were obtained from healthy donor mothers with written informed consent. PDB-MSCs were isolated through enzymic digestion and density gradient centrifugation; the 4th passage cells were identified by cellular morphology, cell adipogenic and osteogenic differentiation, and phenotype evaluation. Forty-two 4-5-week-old BALB/c female nude mice were randomly divided into experimental group (n=21) and control group (n=21). The 4th passage PDB-MSCs solution (200 μL, 5×106/mL) was injected into the mice of experimental group via caudal vein; the mice of control group were given equal volume of PBS. The full-thickness skin defect model of 1.5 cm×1.5 cm in size was made after 3 days. The wound healing was observed generally at 1, 2, 4, 7, 14, 18, 21, 25, and 30 days after operation, and the wound healing rate was calculated after wound decrustation. HE staining was used to observe the wound repair at 1, 7, 14, 21, and 31 days; immunofluorescent staining was used for cellular localization at 7, 14, and 31 days after operation. ResultsCells isolated from human placenta were MSCs which had multipotential differentiation ability and expressed MSCs phenotype. Animals survived to the end of the experiment. The general observation showed that the experimental group had a faster skin repairing speed than the control group; the time for decrustation was 12-14 days in experimental group and was 14-17 days after operation in the control group. The wound healing rate of experimental group was significantly higher than that of control group at 14, 18, and 21 days (t=4.001, P=0.016; t=3.380, P=0.028; t=3.888, P=0.018), but no significance was found at 25 and 30 days (t=1.565, P=0.193; t=1.000, P=0.423). HE staining showed lower inflammatory reaction, and better regeneration of the whole skin and glands with time in the experimental group. The immunofluorescent staining was positive in skin defect area of experimental group at different time points which displayed that human PDB-MSCs existed. ConclusionThrough enzymic digestion and density gradient centrifugation, PDB-MSCs can be obtained. Pre-stored PDB-MSCs can mobilize to the defect area and participate in repair of nude mice skin.
ObjectiveTo investigate the effect of circulating estrogen level on the outcome of free fat grafting in nude mice.MethodsEighteen female nude mice aged 6-8 weeks (weighing, 20-25 g) were randomly divided into 3 groups (n=6). The nude mice in the ovariectomized group were treated with ovariectomy. The nude mice in the high estrogen group and the normal estrogen group only made the same incision to enter the peritoneum without ovariectomy. The nude mice in the high estrogen group were given the estradiol (0.2 mg/g) every 3 days for 30 days. The other two groups were given the same amount of PBS every 3 days. At 30 days after operation, the tail vein blood of nude mice in 3 groups were detected by estradiol ELISA kit, and the free fat (0.3 mL) donated by the females was injected into the sub-scalp of nude mice. After 8 weeks of fat grafting, the samples were taken for gross observation and weighing, and the prepared slices were stained with HE staining, CD31-perilipin fluorescence staining, immunohistochemical staining of uncoupling protein 1 (UCP1), and immunofluorescence staining of estrogen receptor α. The diameter of adipocytes and vascular density of adipose tissue were measured. The mRNA expressions of UCP1 and estrogen receptor α were detected by realtime fluorescence quantitative PCR (qRT-PCR).ResultsAll nude mice survived during experiment. ELISA test showed that the concentration of estradiol significantly decreased in the ovariectomized group and increased in the high estrogen group compared with the normal estrogen group (P<0.05). At 8 weeks after fat grafting, the graft volume from large to small was ovariectomized group, normal estrogen group, and high estrogen group. There was significant difference in wet weight between the ovariectomized group and high estrogen group (P<0.05). Section staining showed that compared with the normal estrogen group, the adipocytes in the ovariectomized group were larger, the expression of peri-lipoprotein was weaker, the vascular density decreased, and the expressions of UCP1 was negative, and the estrogen receptor α positive cells reduced. The above observation results in the high estrogen group were contrary to those in the ovariectomized group. There were significant differences in the diameter of adipocytes, the vascular density of adipose tissue, the number of the estrogen receptor α positive cells between groups (P<0.05). The results of qRT-PCR showed that the mRNA expressions of UCP1 and estrogen receptor α significantly increased in the high estrogen group and decreased in the ovariectomized group compared with the normal estrogen group, and the differences were significant (P<0.05).ConclusionThe level of circulating estrogen has a significant effect on the outcome of free fat grafting in nude mice. Low estrogen level leads to hypertrophy of graft adipocytes, while high estrogen level leads to the production of a large amount of beige fat and high vascular density in fat grafts, which may be related to the activation of estrogen receptor α on adipocytes.
ObjectiveTo investigate the inhibitory effect of short hairpin RNA (shRNA) mediated contactin-1 (CNTN1) gene silencing on growth of human breast cancer cell line MDA-MB-468 transplanted tumors in nude mice.MethodsEighteen nude mice (4-week-old male BALB/c) were randomly equally divided into three groups: blank control group, empty vector group, and silencing group. The MDA-MB-468 cells (blank control group), MDA-MB-468 cells transfected by nonsense shRNA (empty vector group), and MDA-MB-468 cells transfected by shRNA (silencing group) were collected in the logarithmic growth period, respectively. The subcutaneous tumor models of nude mice were prepared by the subcutaneous injection of the different group cells. The tumor growth was observed and the expressions of CNTN1 and Ki-67 proteins in the transplanted tumor were detected by the immunohistochemistry.ResultsThe xenograft models of human breast cancer cells were established successfully. The tumor growth in the silencing group was significantly slower than that of the other two groups at every 3 d point (P<0.05). The tumor volume and the tumor weight in the silencing group were significantly smaller or slighter than those of the other two groups at day 18 (P<0.05). The positive rates of CNTN1 and Ki-67 protein expressions in the tumor tissues of the silencing group were lower than those of the other two groups (P<0.05), respectively.ConclusionSilencing expression of CNTN1 gene might inhibit growth of breast cancer cell line MDA-MB-468 transplanted tumors in mude mice.
【摘要】 目的 观察低频超声（20 kHz）辐照联合静脉注射微泡造影剂SonoVue对裸鼠前列腺癌（Du145）移植瘤的抑瘤效应，并探讨其可能的抑瘤机制。 方法 通过细胞移植和瘤块移植方法建立24只裸鼠前列腺癌Du145移植瘤模型，随机分为超声微泡组、单纯超声组、单纯微泡组和对照组，每组各6只。超声微泡组：尾静脉注射0.2 mL SonoVue的同时对瘤体行20 kHz超声辐照，辐照强度200 mW/cm2；单纯超声组：尾静脉注射生理盐水0.2 mL，同时超声辐照2 min；单纯微泡组：尾静脉注射SonoVue 0.2 mL同时行假照，各组均隔天1次，共3次，对照组不做任何处理。治疗后测量瘤体大小，绘制瘤体生长曲线，计算抑瘤率。首次治疗后14 d剥离瘤体，通过光学显微镜、电子显微镜观察肿瘤组织病理改变。免疫组织化学方法观察CD34阳性染色血管，计算肿瘤微血管密度（micro vessel density，MVD），比较各组间MVD的差异。 结果 24只裸鼠均成功植瘤。治疗后超声微泡组瘤体体积均数明显小于其他3组（Plt;0.05），抑瘤率为62.7%。光学显微镜下超声微泡组瘤体组织大部分损伤坏死，电子显微镜下超声微泡组肿瘤内微血管的内皮细胞损伤，线粒体肿大，基底膜断裂。超声微泡组瘤体内CD34阳性染色微血管数减少，其MVD值显著低于其他各组。 结论 20 kHz低频超声辐照联合微泡造影剂SonoVue可有效抑制裸鼠人前列腺癌移植瘤的生长，其抑瘤机制可能是通过超声空化效应破坏肿瘤的微血管实现的。【Abstract】 Objective To investigate the anti-tumor effect induced by low-frequency ultrasound (20 kHz) radiation combined with intravenous injection of microbubbles on human prostate carcinoma xenograft in nude mice, and to discuss its probable mechanism. Methods Human prostate carcinoma xenograft model in 24 nude mice were established with human prostate carcinoma Du145 cells inoculation and sub-graft through mice, which were randomly divided into ultrasound+microbubble, ultrasound, microbubble, and control group, with 6 mice in each group. In the ultrasound+microbubble group, 0.2 mL SonoVue was injected intravenously, followed by 20 kHz ultrasound exposure of 200 mW/cm2 at every other day for 3 times totally. Mice in the ultrasound group and the microbubbles group were only treated with ultrasound radiation and microbubbles injection, respectively. The volume of gross tumors was measured, and tumor growth curve was drawn. The ratio of anti-tumor growth was calculated. The mice were sacrificed 14 days after the last ultrasound exposure. Specimens of the exposed tumor tissues were obtained and observed pathologically under light microscope and transmission electron microscope. CD34 positive vessels were counted in all the tumor slices by immunohistochemistry, and the micro-vessels density（MVD）of the tumor was also calculated. Results Du145 prostate tumor model was successfully established in all the mice. The average gross tumor volume of the ultrasound+microbubble group was significant lower compared with the other two groups after treatment (Plt;0.05), and the ratio of anti-tumor growth was 62.7%. Histological examination showed signs cell injury in the ultrasound+microbubble group. Electron microscopic examination revealed that the endothelium of vessels in the tumor was injured. The amount of CD34 positive vessels and MVD of the ultrasound+microbubble group was less than that of the other two groups. Conclusion The low-frequency ultrasound of 20 kHz exposure combined with microbubbles can be used to ablate human prostate carcinoma xenograft in nude mice, which is probably realized through micro-vessels destroyed by cavitation effect of ultrasound.
Objective To study effect of carcinoembryonic antigen (CEA) positive targeted lymphocytes on gastric cancer cells in vitro and in vivo. Methods The peripheral blood mononuclear cells (PBMCs) were isolated from the peripheral blood of healthy volunteers. The recombinant vector anti-CEA-scFv-CD3ζ-pcDNA3.0 was transfected into the PBMCs by lipofectamine 2000, by this means, the CEA special lymphocytes were obtained. Meanwhile, the PBMCs transfected with empty plasmid pcDNA3.0 were used as control (empty vector lymphocytes). The different lymphocytes and gastric cancer cells (CEA positive KATOⅢ gastric cancer cells and CEA negative BGC-823 gastric cancer cells) were co-cultured, then the ability to identify the gastric cancer cells and it’s effect on apoptosis of gastric cancer cells were observed at 24 h or 36 h later respectively. The CEA special lymphocytes and empty vector lymphocytes were injected by the tail vein of nude mice bearing gastric cancer cells, then it’s effect on the tumor was observed. Results ① The CEA special lymphocytes could strongly identify the KATOⅢ gastric cancer cells (identification rate was 72.3%), which could weakly identify the BGC-823 gastric cancer cells (identification rate was 7.8%). ② The apoptosis rate of the co-culture of CEA special lymphocytes and KATOⅢ gastric cancer cells was significantly higher than that of the co-culture of empty vector lymphocytes and KATOⅢ gastric cancer cells (P=0.032), which had no significant difference between the co-culture of CEA special lymphocytes and BGC-823 gastric cancer cells and the co-culture of empty vector lymphocytes and BGC-823 gastric cancer cells (P=0.118). ③ The tumor volume of the co-culture of CEA special lymphocytes and KATOⅢ gastric cancer cells was significantly smaller than that of the co-culture of empty vector lymphocytes and KATOⅢ gastric cancer cells (F=5.010, P<0.01) or the co-culture of CEA special lymphocytes and BGC-823 gastric cancer cells (F=4.982, P<0.01), which had no significant difference between the co-culture of CEA special lymphocytes and BGC-823 gastric cancer cells and the co-culture of empty vector lymphocytes and BGC-823 gastric cancer cells (F=1.210, P>0.05). Conclusion CEA special lymphocytes can promote cell apoptosis and inhabit tumor reproduction of CEA positive gastric cancer cells in vitro and in vivo.
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 Col I A1 antisense oligodeoxyneucleotide (ASODN) has inhibitory effect on collagen synthesis in cultured human hypertrophic scar fibroblasts. To investigate the effects of intralesional injection of Col I A1 ASODN on collagen synthesis in human hypertrophic scar transplanted nude mouse model. Methods The animal model of humanhypertrophic scar transplantation was established in the 60 BALB/c-nunu nude mice (specific pathogen free grade, weighing about 20 g, and aged 6-8 weeks) by transplanting hypertrophic scar without epidermis donated by the patients into the interscapular subcutaneous region on the back, with 1 piece each mouse. Fifty-eight succeed models mice were randomly divided into 3 groups in accordance with the contents of injection. In group A (n=20): 5 μL Col I A1 ASODN (3 mmol/L), 3 μL l iposome, and 92 μL Opti-MEM I; in group B (n=20): 3 μL l iposome and 97 μL Opti-MEM I; in group C (n=18): only 100 μL Opti-MEM I. The injection was every day in the first 2 weeks and once every other day thereafter. The scar specimens were harvested at 2, 4, and 6 weeks after injection, respectively and the hardness of the scar tissue was measured. The collagens type I and III in the scar were observed under polarized l ight microscope after sirius red staining. The ultrastructures of the scar tissues were also observed under transmission electronic microscope (TEM). Additionally, the Col I A1 mRNAs expression was determined by RT-PCR and the concentrations of Col I A1 protein were measured with ELISA method. Results Seventeen mice died after intralesional injection. Totally 40 specimens out of 41 mice were suitable for nucleic acid and protein study, including 14 in group A, 13 in group B, and 14 in group C. The hardness of scars showed no significant difference (P gt; 0.05) among 3 groups at 2 weeks after injection, whereas the hardness of scars in group A was significantly lower than those in groups B and C at 4 and 6 weeks (P lt; 0.05), and there was no significant difference between groups B and C (P gt; 0.05). The collagen staining showed the increase of collagentype III in all groups, especially in group A with a regular arrangement of collagen type I fibers. TEM observation indicated that there was degeneration of fibroblasts and better organization of collagen fibers in group A, and the structures of collagen fibers in all groups became orderly with time. The relative expressions of Col I A1 mRNA and the concentrations of Col I A1 protein at 2 and 4 weeks after injection were significant difference among 3 groups (P lt; 0.05), and they were significantly lower in group A than in groups B and C (P lt; 0.05) at 6 weeks after injection, but no significant difference was found between groups B and C (P gt; 0.05). Conclusion Intralesional injection of Col I A1 ASODN in the nude mice model with human hypertrophic scars can inhibit the expression of Col I A1 mRNA and collagen type I, which enhances the mature and softening of the scar tissue. In this process, l iposome shows some assistant effect.
ObjectiveTo discuss the possibility of constructing injectable tissue engineered adipose tissue, and to provide a new approach for repairing soft tissue defects.MethodsHuman adipose-derived stem cells (hADSCs) were extracted from the lipid part of human liposuction aspirate by enzymatic digestion and identified by morphological observation, flow cytometry, and adipogenic induction. The hADSCs underwent transfection by lentivirus vector expressing hepatocyte growth factor and green fluorescent protein (HGF-GFP-LVs) of different multiplicity of infection (MOI, 10, 30, 50, and 100), the transfection efficiency was calculated to determine the optimum MOI. The hADSCs transfected by HGF-GFP-LVs of optimal MOI and being adipogenic inducted were combined with injectable fibrin glue scaffold, and were injected subcutaneously into the right side of the low back of 10 T-cell deficiency BALB/c female nude mice (transfected group); non-HGF-GFP-LVs transfected hADSCs (being adipogenic inducted) combined with injectable fibrin glue scaffold were injected subcutaneously into the left side of the low back (untransfected group); and injectable fibrin glue scaffold were injected subcutaneously into the middle part of the neck (blank control group); 0.4 mL at each point. Twelve weeks later the mice were killed and the implants were taken out. Gross observation, wet weight measurement, HE staining, GFP fluorescence labeling, and immunofluorescence staining were performed to assess the in vivo adipogenic ability of the seed cells and the neovascularization of the grafts.ResultsThe cultured cells were identified as hADSCs. Poor transfection efficiency was observed in MOI of 10 and 30, the transfection efficiency of MOI of 50 and 100 was more than 80%, so the optimum MOI was 50. Adipose tissue-like new-born tissues were found in the injection sites of the transfected and untransfected groups after 12 weeks of injection, and no new-born tissues was found in the blank control group. The wet-weight of new-born tissue in the transfected group [(32.30±4.06) mg] was significantly heavier than that of the untransfected group [(25.27±3.94) mg] (t=3.929, P=0.001). The mature adipose cells in the transfected group [(126.93±5.36) cells/field] were significantly more than that in the untransfected group [(71.36±4.52) cells/field] (t=30.700, P=0.000). Under fluorescence microscopy, some of the single cell adipocytes showed a network of green fluorescence, indicating the presence of GFP labeled exogenous hADSCs in the tissue. The vascular density of new-born tissue of the transfected group [(16.37±2.76)/field] was significantly higher than that of the untransfected group [(9.13±1.68)/field] (t=8.678, P=0.000).ConclusionThe hADSCs extracted from the lipid part after liposuction can be used as seed cells. After HGF-GFP-LVs transfection and adipose induction, the hADSCs combined with injectable fibrin glue scaffold can construct mature adipose tissue in vivo, which may stimulate angiogenesis, and improve retention rate of new-born tissue.
ObjectiveTo investigate the survival rate of core fat tissue with different diameters by advanced fat harvesting instrument. MethodsBased on core fat transfer by 1 mL syringe, the fat harvesting instrument was modified with different diameters, including 4, 6, 8, and 10 mm respectively. Between May 2014 and April 2015, the fat harvesting instrument with diameters of 4, 6, 8, and 10 mm was respectively used to harvest abdominal fat in 3 of 12 patients undergoing autologous fat transplantation. The glucose transportation quantities and the fat cell viability were measured. Then 64 nude mice at the age of 3-4 weeks were randomly divided into 4 groups (groups A, B, C, and D, n=16). And 0.5 mL fat harvested with diameters of 4, 6, 8, and 10 mm was implanted into the dorsal subcutaneous space. After fat transplantation, the mice survival and the appearance at the recipient site were observed. At 1, 2, 4, and 8 weeks after fat transplantation, the grafted fat was harvested for gross, histological and immunohistochemical observations; the intact adipocytes and capillary were counted. ResultsThe glucose transportation quantities gradually increased with increased diameter, showing significant difference among groups (P<0.05). And the fat cell viability had a rising tendency, showing significant differences when comparing groups A and B with group D (P<0.05). With the time passing by, the protuberant appearance became flat at the recipient site, but the appearance of groups C and D was better than groups A and B. Normal shape of the fat and capillary were found in groups C and D. At immediate and 1 week after fat transplantation, there was no significant difference in fat weight among 4 groups (P>0.05); the fat weight of group A was significantly less than that of groups B, C, and D (P<0.05) at 2, 4, and 8 weeks after fat transplantation, and it was significantly less 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). Histological and immunohistochemical observations showed better integrity of the cells, less necrosis, and higher vascular density in group D than groups A, B, and C as time extension. The adipocyte integrity of group A was significantly worse than that of other 3 groups at other time points (P<0.05) except at 1 week (P>0.05). At each time point, the capillary counting had an increasing trend with increased diameter in all groups, showing significant difference among groups (P<0.05). ConclusionWith diameters within 10 mm, the thicker the core fat is transferred, the better integrlity, higher vessel density, and quicker revascularization time can be predicted. So the postoperative appearance could be maintained longer.