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.
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.
Objective To establish a stable colorectal cancer model in liver specific insulin-like growth factor (IGF)-1 deficient (LID) mice and examine the potential relationship between IGF-1 level and risk of mice constitutional colorectal cancer. Methods ①Establishment of a colorectal cancer model: The LID mice, in which IGF-1 level in circulation was 25% of BALB/c mice. Induction of colorectal cancer was achieved by using the 1,1 Dimethylhydrazine (DMH) with hypodermic injection at transverse part. ②Eighty fresh samples of cancer tissues and adjacent tissues were obtained from LID mice (experimental group) and BALB/c mice (control group). The expression of IGF-1 was studied by immunohistochemical assay (SP method). Results ①Weight loss occurred in both experimental group and control group after injection. Compared with the body weight before injection on 18 weeks and 24 weeks in each group, there were significant differences after injection at the same phase in each group (P＜0.05). ②The results of IGF-1 expression in cancer tissues and adjacent tissues: IGF-1 got a diffuse distribution in cancer cell cytoplasm. The positive expressions of IGF-1 in the cancer tissues and their adjacent cancer tissues were 6/7, 2/7 and 13/16, 7/16 respectively in experimental group and control group. There were significant differences between the cancer tissues and adjacent tissues inside both groups (P＜0.05). There were no significant differences inside both of cancer tissues and adjacent tissues respectively between experimental group and control group (Pgt;0.05). Conclusion In the established colorectal cancer model by DMH, IGF-1 plays an important role in the development and progression of colorectal cancer.
Objective To construct and verify a genetically engineered mouse model which is similar to clinical sporadic colorectal cancer and simultaneously expresses KrasLSL-G12D/- and Smad4loxp/loxp genes. Methods The Krastm4Tyj/J mouse and Smad4tm2.1Cxd/J mouse were transformed into the genetic background, and the genotypes of the offspring mice were identified by the PCR to obtain the mice expressed simultaneously KrasLSL-G12D/- and Smad4loxp/loxp genes. The LentivirusCre-IRES-Luciferase was injected into the submucosa of the model mice and the tumorigenicity was observed under the IVIS system. The tumor tissues of the model mice were sampled and the HE staining was used to verify the tumorigenicity of the model mice. Results The genetically engineered mouse model which could simultaneously express KrasLSL-G12D/- and Smad4loxp/loxp genes was obtained by the breeding and selection. The mouse intestinal epithelial cell carcinogenesis was successfully induced by the viral vector containing Cre recombinase. Conclusion Mouse model expressed simultaneously KrasLSL-G12D/- and Smad4loxp/loxp genes is capable of sporadic tumorigenicity by Cre recombinase and could simulate pathological process of human sporadic colorectal cancer.
Objective To investigate the effect of myoblast transplantation on duchenne muscular dystrophy (DMD) and to explore the method and feasibil ity of applying gene therapy to DMD. Methods Myoblast of C57/BL10 mice were cultured using multiple-step enzyme digestion method and differential velocity adherent technique. The morphology of the cells was observed with inverted phase contrast microscope. The cells at passage 4 were labeled with 5-BrdU. Twenty-four DMDmodel mice (mdx mice: aged 4-6 weeks, male, 13.8-24.6 g) were randomly divided into two groups (n=12 per group): group A, 1 × 106/mL labeled myoblast were injected via ven caudal is twice at an interval of 2 weeks; group B: 1 mL DMEM/F12 was injected in the same manner serving as a control group. The mice were killed 4 weeks after operation and the motor abil ity of the mice was detected by one-time exhaustive swimming before their death. HE staining and immunohistochemistry staining observation for 5-BrdU, desmin, and dystrophin (Dys) were preformed, and the imaging analysis was conducted. Results The primary myoblast could be sub-cultured 5-7 days after culture, providing stable passage and sufficient cells. The time of onetime exhaustive swimming was (60.72 ± 5.76) minutes in group A and (47.77 ± 5.40) minutes in group B, there was significant significance between two groups (P lt; 0.01). At 4 weeks after injection, HE staining showed that in group A, there were round and transparent-stained myocytes and the percentage of centrally nucleated fibers (CNF) was 67%; while in group B, there were uneven muscle fiber with such pathological changes as hypertrophia, atrophia, degeneration, and necrosis, and the percentage of CNF was above 80%. Immunohistochemistry staining revealed that the expression of 5-BrdU, desmin, and Dys was positive in group A; while in group B, those expressions were l ittle or negative. Image analysis result displayed that integral absorbency (IA) value of desmin was 489.70 ± 451.83 in group A and 71.15 ± 61.14 in group B (P lt; 0.05) and the ratio of positive area to thetotal vision area was 0.314 3 ± 0.197 3 in group A and 0.102 8 ± 0.062 8 in group B (P lt; 0.05); the Dys IA value was 5 424.64 ± 2 658.01 in group A and 902.12 ± 593.51 in group B (P gt; 0.05) and the ratio of positive area to the total vision area was 0.323 7 ± 0.117 7 in group A and 0.035 2 ± 0.032 9 in group B (P lt; 0.05). Conclusion Myoblast transplantation has certain therapeutic effect on DMD of mice.
ObjectiveTo explore the endothelial cells from human peripheral blood and islet of rat co-transplantation under the renal capsule of diabetic nude mice to improve the survival and function of transplanted islet. MethodsThe endothelial cells from human peripheral blood(5×105)and freshly isolated rat islet cells were co-transplanted under the renal capsule of diabetic nude mice model, then the fasting blood glucose, body weight, peripheral blood C-peptide level, and intraperitoneal glucose tolerance test(IPGTT) were measured to evaluated the islet graft survival and function. ResultsCompared with the control group, the fasting blood glucose level significantly decreased(P < 0.01), peripheral blood C-peptide level rised(P < 0.01), and body weight increased(P < 0.01) of receptor nude mice in experience group, the IPGTT also improved. ConclusionThe endothelial cells from human peripheral blood and islet of rat co-transplan-tation can obviously improve the survival and function of transplanted islet of nude mice.
Objective To investigate how to establish stable mice cervical heart transplantation model. Methods Totally, 40 male C57 mice with the age of 6-8 weeks and weight of 19-24 g were randomly divided into recipients and donors (n=20 in each group). Mice cervical heart transplantation model was established by connecting the ascending aorta of donors to the right cervical common artery of recipients through end to side anastmosis and the pulmonary artery of donors to the right external jugular vein of recipients through end to end anastmosis. Results More than 95% recipients survived after surgery. Cold ischemia time was 15±5 min, warm ischemia time 23±6 min, and the whole operation took about 55±15 min. The recipients survived more than 30 d with functional heart grafts. Histologically, there was no difference between the heart graft one month after the transplantion and the normal heart. Conclusion Cervical heart transplantation of mice model is reliable and feasible, which is easy to monitor the survival condition of heart graft by visual examination and palpation, which will benefit the basic research in transplantation field.
Objective The immunogenicity of tissue engineered skins is still vague, though it has been appl ied cl inically for several years. To observe the evidence of immunologic rejection of tissue engineered skins transplanted to severe combined immunodeficiency (SCID) mice, which are implanted human splenic lymphocytes to construct human immunesystem. Methods Tissue engineered skins and acellular dermic matrix were constructed in vitro. Twenty SCID mice, aging4-6 weeks and weighing 16-17 g, were randomly divided into four groups equally (n=5). The tissue engineered skins, human foreskins from circumcision and acellular dermic matrix were transplanted to groups A, B, and C, respectively; group D was used as a control. After 2 weeks of transplanting, 3 × 107 human splenic lymphocytes were injected into every SCID mouse intraperitoneally. After 4 weeks, the morphology, histology, immunohistochemistry and human IgG immunofluorescence were used to observe immunologic rejection. Results Group A showed that transplanted tissue engineered skins had the bilayer structure of dermis and epidermis, which was similar to the normal human skin structure. Group B showed that the transplanted human foreskins still retained normal structure of human skin. Group C showed that acellular dermic matrix were located in situ and had no sign of degradation. After injecting human splenic lymphocytes into the SCID mice, no inflammatory cells infil itration were observed basically in groups A, C, and D; the inflammatory cells infil itration of group B were significantly higher than that of other 3 groups (P lt; 0.05). The results of anti human keratin 14 monoclonal antibody (mAb) staining and anti human type IV collagen mAb staining were positive in group A; no positive cells for CD3, CD4, and CD8 were observed in groups A, C, and D; and many positive cells for CD3, CD4, and CD8 were observed in group B. The results of IgG immunofluorescence staining was negative in group A, C, and D, and positive in the great vessel wells of group B. Conclusion The immunogenicity of tissue engineered skins is very weak, and tissue engineered skins would not be rejected by host immune system after transplantation.
A multiple-stimuli-responsive drug-conjugated cross-linked micelles was prepared by radical copolymerization. The chemical structure, morphology, and size of the cross-linked micelles were characterized, and the drug loading of the micelle was calculated. The experimental results indicated that the hydrodynamic size of the drug-loaded micelles were about 100 nm, and the as prepared micelles could be degraded and swelled in presence of reducing glutathione (GSH). The low critical solution temperature (LCST) of the micelle was around 39.4℃. According to the experimental results, the micelles will shrink at temperature above the LCST. Subsequently, the accumulative drug release rate was up to 91.78% under acidic (pH 5.0), reductive (GSH 10 mmol/L) and high temperature (42.0℃) conditions mimicking the tumor microenvironment, while a relatively low release rate of 1.12% was observed without stimulation. The drug-conjugated cross-linked micelles showed a strong cell uptake behavior. In the cytotoxicity assay, the micelles exhibited effective anti-cancer activity and excellent biocompatibility. In brief, the experimental results show that the as-prepared drug-conjugated cross-linked micelle exhibits multiple stimuli-responsiveness, which holds great promise for anti-cancer drug delivery.
【Abstract】 Objective To investigate the impact of dermal papillary cells on vascularization of tissue engineered skinsubstitutes consisting of epidermal stem cells and allogeneic acellular dermal matrix. Methods Human foreskins from routinecircumcisions were collected to separate epidermal cells by using dispase with trypsogen. Collagen type IV was used to isolateepidermal stem cells from the 2nd and 3rd passage keratinocytes. Dermal papilla was isolated by the digestion method of collagenaseI from fetus scalp and cultured in routine fibroblast medium. Tissue engineered skin substitutes were reconstructed by seedingepidermal stem cells on the papillary side of allogeneic acellular dermis with (the experimental group) or without (the controlgroup) seeding dermal papillary cells on the reticular side. The two kinds of composite skin substitutes were employed to cover skindefects (1 cm × 1 cm in size) on the back of the BALB/C-nu nude mice (n=30). The grafting survival rate was recorded 2 weeks aftergrafting. HE staining and immunohistochemistry method were employed to determine the expression of CD31 and calculate themicrovessel density at 2 and 4 weeks after grafting. Results Those adhesion cells by collagen type IV coexpressed Keratin 19 andβ1 integrin, indicating that the cells were epidermal stem cells. The cultivated dermal papillary cells were identified by expressinghigh levels of α-smooth muscle actin. The grafting survival rate was significantly higher in experimental group (28/30, 93.3%), thanthat in control group (24/30, 80.0%). HE staining showed that the epithelial layer in experimental group was 12-layered with largeepithelial cells in the grafted composite skin, and that the epithelial layer in control group was 4-6-layered with small epithelial cells.At 2 and 4 weeks after grafting, the microvessel density was (38.56 ± 2.49)/mm2 and (49.12 ± 2.39)/mm2 in experimental group andwas (25.16 ± 3.73)/mm2 and (36.26 ± 3.24)/mm2 in control group respectively, showing significant differences between 2 groups(P lt; 0.01). Conclusion Addition of dermal papillary cells to the tissue engineered skin substitutes can enhance vascularization,which promotes epidermis formation and improves the grafting survival rate.