Objective To develop a new method for a tissue engineered vascular graft by combining endothelial cells and an acelluarized allogenic matrix. Methods Acellularized matrix tubes were obtained by a 0.1% trypsin and 0 02% EDTA solution for 24 hours and 1% Triton X 100 for 176 hours, respectively. Endothelial cells were isolated from alloaorta and expanded in vitro. Finally, the inner surface of acellularized matrix was reseeded with endothelial cells. Acellularity and reseeding were analysed by light microscopy and scanning electron microscopy. Results The acellularization procedure resulted in an almost complete removal of the original cells and the loose three-dimensional (3D) matrix. The acellular matrix could be reseeded with expanded endothelial cells in vitro, and endothelial cells had the potential of spread and proliferation. Conclusion Acellular matrix produces by Tritoon X-100 and trypsin possesses satisfactory biocompatibility for allogenic endothelial cell. Vascular grafts can be generated in vitro by a combination of endothelial cells and allogenic acelluarized matrix.
Abstract: Objective To study the expression of E-selectin on vascular endothelial cells of nude mice liver induced by esophageal carcinoma cells, in order to find out the function of E-selectin in the metastasis of esophageal carcinoma into the liver. Methods Twelve Balb/c nude mice aged from 6 to 8 weeks with their weight ranged between 20 and 25 grams were selected in our research. The mice were equally distributed into the experimental group and the control group(n=6). EC9706 cell solution (5×10.6/0.02 ml) were injected beneath the splenic capsule of the mice in the experimental group. One hour later, spleen was removed. For the mice in the control group, after laparotomy, phosphate buffer without EC 9706 was injected beneath the splenic capsule and spleen was also removed one hour after the injection. Eight hour later, we resected the liver of the nude mice, and expression of E-selectin on vascular endothelial cells of the liver was detected with reverse transcription polymerase chain reaction (RT-PCR) and immunohistochemistry (IHC). Results In the experimental group, 8 hours after injection of EC9706 cells (5×10.6), the results of RT-PCR showed expression of E-selectin mRNA in the liver, and IHC showed a positive protein expression of E-selectin in the cytosol and membrane of hepatic sinus vessels.However, no E-selectin mRNA expression was found in the control group and IHC showed a negative protein expression of E-selectin. Conclusion Human esophageal carcinoma cell line EC9706 can induce balb/c mice liver vascular endothelial cell E-selectin expression, which shows that EC9706 may stay in the liver and form etastatic focus.
Objective To study the biological behavior of osteoblast and vascular endothelial cell culture. Methods The osteoblasts and vascular endothelial cells were obtained from calvarial bone and renal cortox of 2-week rabbits respectively. The experiment were divided into group A (osteoblasts), group B (vascular endothelial cells) and group C(co-cultured osteoblasts and vascular endothelial cells). The cells were identified with cytoimmunochemical staining. The cellular biological behavior and compatibilitywere observed under inverted phase contrast microscope and with histological staining. The cells viability and alkaline phosphatase(ALP) activity were measured. Results The cytoimmunochemical staining showed that the cultured cells were osteoblasts and vascular endothelial cells .The cellular compatibility of osteoblasts and vascular endothelial cells was good. The ALP activity was higher in group C than in group A and group B(P＜0.01), and it was higher in group A than in group B(P＜0.05). In group C, the cellproliferation were increased slowly early, but fast later. Conclusion Thecellular compatibility of osteoblasts and vascular endothelial cells were good. The vascular endothelial cells can significantly increased the osteoblast viability and ALP activity,and the combined cultured cells have greater proliferation ability.
In order to study the effect of vascular endothelial cell growth factor (VEGF) on the survival of skin flap 30 SD rats were used. A randomized flap measuring 7.5 cm x 3.0 cm was created on the back of each SD rat. The treatment group (n = 10) received VEGF 40 ng/flap by subcutaneous injection with microinjector during and 24 hours after operation. The control groups received heparin 16 U/flap (n = 10) or normal saline 800 microliters/flap (n = 10). After operation, on the 3rd and 11th day, the survival rate of the skin flaps and the dermovascular density of each flap were investigated by histological and histo-morphometrical examination. The results showed that there was no significant difference in the survival rate between the treatment group and the controls on the 3rd day after operation, while on the 11th day, there was a significant difference between them, and the survival rate was much higher in the treatment group. Besides, dermovascular density was much more increased in the treatment group than that in the controls, especially in the distal 1/3 of the flap (P lt; 0.02). The conclusion was that VEGF could .
Objective To compare the effects of flap delay and vascular endothelial growth factor (VEGF) on the viability of the rat dorsal flap. Methods Thirty rats were divided into 3 groups: saline group, flap delay group and VEGF group. The rats in flap delay group underwent flap delay by keeping bipedicle untouched, and the cranial pedicle was cut 7 days later. The rats in VEGF group were given VEGF solution locally when the flaps were elevated in the operation. The ratsin saline group were given saline solution in the same way. Five days after thesingle pedicle flaps were performed, the flap survival rate was measured. Theflap tissues were collected to measure and analyze the microvascular density, diameter and sectional area by immunochemical method. Results The flap survival rate of flap delay group was similar to that of VEGF group andthere is no statistically significant difference(Pgt;0.05). The vascular diameter of flap delay group was much larger than that of saline group and VEGF group, showing statistically significant difference (Plt;0.05). The vascular density of VEGF group was much higher than that of saline group and flap delay group, showing statistically significant difference (Plt;0.05). The vascular sectional area of flap delay group was similar to that of VEGF group(Pgt;0.05). Conclusion The change in the flap after flap delayis manifested as obvious dilatation of microvessels, while the change in the flap after the injection of VEGF is manifested as obvious vascular proliferation. Both flap delay and VEGF can increase the vascular sectional area and the viability of the flap, but the mechanism is different.
Objective To study the differenation of adult marrow mesenchymal stem cells(MSCs) into vascular endothelial cells in vitro and to explore inducing conditions. Methods MSCs were isolated from adult marrow mononuclear cells by attaching growth. MSCs were divided into 4 groups to induce: the cells seeded at a density of 5×103/cm2 in 2% and 15% FCS LDMEM respectively (group1 and group 2)， at a density of 5×104/cm2 in 2% and 15% FCS LDMEM respectively (group 3 and group 4); vascular endothelial growth factor(VEGF) supplemented with Bovine pituitary extract was used to induce the cell differentiation. The differentiated cells were identified by measuring surfacemarks (CD34, VEGFR2, CD31 and vWF ) on the 14th day and 21st day and performed angiogenesis in vitroon the 21st day.The cell proliferation index（PI）of different inducing conditions were measured. Results After induced in VEGF supplemented with Bovine pituitary extract, the cells of group 3 expressed the surface marks CD34, VEGFR-2, CD31 and vWF on the 14th day, the positive rates were 8.5%, 12.0%, 40.0% and 30.0% respectively, and on the 21st day the positive ratesof CD34 and VEGFR2 increased to 15.5％ and 20.0％, while the other groups did not express these marks; the induced cells of group 3 showed low proliferating state(PI was 10.4%) and formed capillary-like structure in semisolid medium. Conclusion Adult MSCs can differentiate into vascular endothelial cellsafter induced by VEGF and Bovine pituitary extract at high cell densities and low proliferatingconditions，suggesting that adult MSCs will be ideal seed cells forthe therapeutic neovascularization and tissue engineering.
Objective To investigate the role of vascular endothelial growth factor-C (VEGF-C) and its receptors in the formation of lymphatic vessels and lymphatic metastasis in gastric cancer. Methods By the domestic and overseas literatures review, the expressions of VEGF-C and its receptors in gastric cancer, their role in tumor lymphatic metastasis and prospect in treatment of gastric cancer were summarized.Results There was a significant correlation between VEGF-C and its receptors and the formation of lymphatic vessels and lymphatic metastasis in gastric cancer. VEGF-C high expression might be an early event in lymphatic metastasis and could be considered as an independent predictive factor of lymphaticmicrometastasis. By inhibition of gastric cancer cell from secrete VEGF-C or blockage of the interaction of VEGF-C with VEGFR3, it was possible to inhibit tumor angiogenesis and the invasion and distant spread of cancer cells, thereby decreased mortality and improve survival. ConclusionVEGF-C and its receptors may promote the formation of lymphatic vessels and lymphatic metastasis in gastric cancer. It may be an effective way to gastric cancer for the treatments against VEGF-C and its receptors.
ObjectiveTo summarize the progress on the injury mechanism of vascular endothelial cells in atherosclerosis.MethodsThe latest progress was reviewed in recent literatures.ResultsAll kinds of etiological factors have activated NF-kappa B and cytokines in the development of atherosclerosis, which lead to expression of cell adhesive molecules and adhesion of monocytes to vascular endothelial cells.A variety of inflammatory mediums are released, which can directly damage endothelial cells.Besides, the inflammatory mediums make monocytes and neutrophils attach to endothelial cells by immune mechanisms, which injure the endothelial cells more severely. Meanwhile the damaged membrance structure leads to the production of AECA which activates the complementary system. Then the vascular endothelial cell injury is aggravated and the development of atherosclerosis accelerated. ConclusionIt is very important to recognize the injury mechanism of vascular endothelial cells in the development of atherosclerosis for prevention and treatment of atherosclerosis.
Objective To explore the effects of Zhaoke defibrase and anti alpha;vbeta;3mAb (23C6) on the adhesion and immigration of bovine retinal vascular endothelial cells. Methods The culture dishes coated with vitronectin (Vn) and collagen，assays of adhesion and immigration were performed 60 minutes after different concentration of Zhaoke defibrase and anti-alpha;vbeta;3 mAb was added to the bovine retinal vascular endothelial cells. The apoptosis of bovine retinal vascular endothelial cells induced by Zhaoke defibrase and anti-alpha;vbeta;3 mAb was detected by electron microscopy. Results Both Zhaoke defibrase and anti-alpha;vbeta;3 mAb inhibited the adhesion and immigration of bovine retinal vascular endothelial cells in a dose-dependent manner. The inhibited concentration (IC50) of Zhaoke defibrase was less than 0.05 mu;mol/L, while (IC50) of anti-alpha;vbeta;3 mAb was more than 2.5 mu;mol/L. 81.8% endothelial cells adhering to Vn were inhibited by 0.1 mu;mol/L Zhaoke defibrase, while 76.3% by endothelial cells adhering to Vn were inhibited by 10 mu;mol/L anti-alpha;vbeta;3 mAb. Typical apoptosis cells were found in bovine retinal vascular endothelial cells after affected by Zhaoke defibrase and anti-alpha;vbeta;3 mAb. Conclusion Both Zhaoke defibrase and anti- alpha;vbeta;3mAb can significantly inhibit the adhesion and immigration of bovine retinal vascular endothelial cells to extracellular matrix， and the mechanism may lie in inducing the apoptosis of endothelial cells. (Chin J Ocul Fundus Dis, 2005,21:118-121)
Objective To establish a simple and efficient method to isolate and culture the umbilical vein vascular endothelial cells in canine. Methods Twelve umbilical cords [(13.0 ± 1.5) cm in length] were taken from 12 newborn pups of Beagles. And then the vascular endothelial cells were isolated from these umbilical cords digested by 1% collagenase type I for 5, 7, and 10 minutes respectively (4 umbilical cords in each group). After cultured, the vascular endothelial cells were identified by morphology, immunofluorescence, and flow cytometry. And the growth curvature of umbilical vein vascular endothelial cells was detected by MTT assay. Results Few vascular endothelial cells were collected at 5 and 10 minutes after digestion; many vascular endothelial cells were seen at 7 minutes, and became cobblestone with culture time, with a large nucleus; after passage, cell morphology had no obvious change. Fluorescence microscope results showed that positive von Willebrand factor (vWF) and CD31 cells were observed in most of cells. The flow cytometry test displayed that the positive cell rates of vWF and CD31 were 99.0% ± 0.7% and 98.0% ± 1.2%, respectively. The above results indicated that cultured cells were vascular endothelial cells. MTT assay showed that vascular endothelial cells proliferation increased significantly with culture time. Conclusion Enzyme digestion is a convenient method to isolate vascular endothelial cells from canine umbilical vein, and a large number of cells and high purity of cells can be obtained by the method.