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 To investigate the effect of hepatocyte-l ike cells induced by CD34+ cells in vitro on the repair of the injured hepatic tissues of mice in vivo. Methods Mononuclear cells were isolated from umbil ical blood by density gradient centrifugation and enriched CD34+ cells were obtained. The cells were (1 × 105 cells/mL) cultured in serumfreemedium containing stem cell factor (SCF), hepatocyte growth factor (HGF), EGF, oncostatin M (OSM), bFGF (the concentration were 50, 20, 20, 10, 10 ng/mL respectively) in vitro for 10 days. Forty-eight 6-week-old female ICR mice werechosen to prepare l iver injury model by injecting carbon tetrachloride and 2-acetylamionoflu-orene. The mice were randomly divided into two groups (n=24 per group): the experimental group, the cultured cells were injected into the mice through the tail vein; the control group, the equivalent serum-free medium was injected. Six mice from each group were killed at 7, 14, 21, and 28 days after operation to receive HE staining, PCR gel electrophoresis, immunohistochemistry staining, and hepatic function detection. Results HE staining: the morphology of injured hepatic tissues in the control group recovered to normal 28 days after operation, while in the experimental group, it recovered to normal 14 days after operation. PCR gel electrophoresis and immunohistochemistry staining: the cells expressing human serum albumin were detected in the hepatic tissue of the experimental group at each time point after operation; while in the control group, no such cells were detected within 28 days after operation. Hepatic function detection: the activity of alanine aminitransperase in the control group recovered to normal 14 days after operation; the mean activity of aspartate aminotransferase of two groups failed to recover within 28 days. Conclusion The hepatocyte-l ike cells induced by CD34+ cells in vitro can promote the morphological and functional recovery of the injured hepatic tissue in mice. Moreover, it can be transformed into human-derived hepatic cells in l iver-injured mice.
ObjectiveTo study the feasibility of human adipose-derived stem cells (hADSCs) combined with small intestinal submucosa powder (SISP)/chitosan chloride (CSCl)-β-glycerol phosphate disodium (GP)-hydroxyethyl cellulose (HEC) for adipose tissue engineering.
MethodshADSCs were isolated from human breast fat with collagenase type I digestion, and the third passage hADSCs were mixed with SISP/CSCl-GP-HEC at a density of 1×106 cells/mL. Twenty-four healthy female nude mice of 5 weeks old were randomly divided into experimental group (n=12) and control group (n=12), and the mice were subcutaneously injected with 1 mL hADSCs+SISP/CSCl-GP-HEC or SISP/CSCl-GP-HEC respectively at the neck. The degradation rate was evaluated by implant volume measurement at 0, 1, 2, 4, and 8 weeks. Three mice were euthanized at 1, 2, 4, and 8 weeks respectively for general, histological, and immunohistochemical observations. The ability of adipogenesis (Oil O staining), angiopoiesis (CD31), and localized the hADSCs (immunostaining for human Vimentin) were identified.
ResultsThe volume of implants of both groups decreased with time, but it was greater in experimental group than the control group, showing significant difference at 8 weeks (t=3.348, P=0.029). The general observation showed that the border of implants was clear with no adhesion at each time point;fat-liked new tissues were observed with capillaries on the surface at 8 weeks in 2 groups. The histological examinations showed that the structure of implants got compact gradually after injection, and SISP gradually degraded with slower degradation speed in experimental group;adipose tissue began to form, and some mature adipose tissue was observed at 8 weeks in the experimental group. The Oil O staining positive area of experimental group was greater than that of the control group at each time point, showing significant difference at 8 weeks (t=3.411, P=0.027). Immunohistochemical staining for Vemintin showed that hADSCs could survive at each time point in the experimental group;angiogenesis was most remarkable at 2 weeks, showing no significant differences in CD31 possitive area between 2 groups (P>0.05), but angiogenesis was more homogeneous in experimental group.
ConclusionSISP/CSCl-GP-HEC can use as scaffolds for hADSCs to reconstruct tissue engineered adipose.
Objective To investigate the feasibility and characteristic of tissue engineered testicular prosthesis with highdensity polyethylene(HDPE，trade name: Medpor) and polyglycolic acid(PGA). Methods The chondrocytes were isolated from the swine articular.The PGA scaffold was incorporated with medpor which semidiameters were 6mmand 4mm respectively.Then, the chondrocytes (5×10 7/ml) were seeded onto Medpor-PGA scaffold and cultured for 2 weeks. The ten BALB／C mice were divided into two groups randomly(n=5). In the experimental group, the cell-scaffold construct was implanted into subcutaneous pockets on the back of nude mice. In the control group, the Medpor-PGA scaffold was implanted. The mice of two groups were sacrificed to harvest the newly formed cartilage prosthesis after 8 weeks. Macroscopy, histology and immunohistochemistry observations were made. Results The gross observation showed that on changes were in shape and at size, the color and elasticity were similar to that of normal cartilage and that the cartilage integrated with Medpor in the experimental group; no cartilage formed and fiberlike tissue was found in the control group. HE staining showed that many mature cartilage lacuna formed without blood vessel and some PGA did not degradated completely. Toluidine blue staining showed extracellular matrix had metachromia. Safranin O-fast green staining showed that many proteoglycan deposited and collagen type Ⅱ expression was bly positive. In the control group, Medpor was encapsulated by fiber tissue with rich blood vessel. Conclusion The newly formed complex of Medpor-PGA and cells was very similar to testicle in gross view and to normal cartilage in histology. This pilot technique of creating testicular prosthesis by incorporating tissue-engineered cartilage with Medpor demonstrated success.
ObjectiveTo establish an animal model of anaplastic thyroid cancer with high metastatic activity as in human body. MethodsHuman anaplastic thyroid cancer cell line TAK was injected into one of the lateral lobes of the thyroid gland, as well as in the subcuitis in a series of nude mice. Mice were sacrificed when found moribund, and autopsy and histology were performed subsequently.ResultsThe implantation of human anaplastic thyroid cancer cells in an ectopic enviroment did not permit expression of metastasis potential. In contrast, intrathyroid implantation did. Lymph node (5/10), lung (3/10) and one metastasis (1/10) were noted upon histological examination. ConclusionAn animal model with high metastatic activity is established when human anaplastic thyroid cancer cell line TAK is implanted orthotopically into nude mice.
AMP-activated protein kinase (AMPK) is involved in the development and progression of tumors including hepatocellular carcinoma (HCC). However, studies on AMPK and tumorigenesis were largely based on experiments in vitro or tumor xenografts model. Here, we introduce a liver-specific AMPKα1 knockout mice model, which is achieved by Alb-Cre recombinase system. The expression of AMPKα1 in the liver of AMPKα1-/--Alb-Cre mice is absent. AMPKα1 knockout in the liver does not affect the growth and histological structure of mouse liver. This model provides a favorable tool to the study of the roles of AMPKα1 in liver metabolism or tumorigenesis.
ObjectiveTo study the expression of lipid associated with neutrophil gelatinase associated lipocalin (NGAL) in nude mice orthotopic pancreatic cancer tissues and the relationship between the occurred and development of pancreatic cancer.
MethodsThe expressions of NGAL mRNA and protein of pancreatic cancer tissues and their adjacent tissues, and normal pancreatic tissues in nude mice were detected by using RT-PCR and immunohistochemical methods.
ResultsThe expressions of NGAL mRNA in pancreatic cancer tissues and adjacent tissues were significantly higher than that in normal pancreatic tissues (P < 0.05), and the expression of NGAL mRNA in pancreatic carcinoma tissues was significantly higher than that in para carcinoma tissues (P < 0.05). The strong positive expression rate of NGAL protein in pancreatic carcinoma tissues was significantly higher than thoes in para carcinoma tissues and normal pancreatic tissues (P < 0.05).
ConclusionsNGAL is highly expressed in pancreatic cancer tissues, and NGAL may be an important regulatory factor in the development of pancreatic 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.
【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.
On the basis of established JF305 cell line from human pancreatic cancer at this university, cell clone technique, cell electrophoresis, flower cytometer, and cancer orthotopically implanted nude mice technique were used to establish the sublines with different metastatic potential from human pancreatic cancer line-JF305 and the nude mice model implanted orthotopically with human pancreatic cancer monoclonal sublines with different metastatic potential. The results showed that the monoclonal cell sublines with different metastatic potential from human pancreatic caner-JF305 and the nude mice model implanted orthotopically with the sublines, would provided a useful method to study the metastatic mechanism of human pancreatic cancer.
