Objective To study the feasibility of transplanting autologous venous endothelial cells, as the liner, to the allogenic vein and to investigate the patency rate after such transplantation. Methods Autologous endothelial cells were gained after the administration of 0.2% collagenase and the centrifugalization of the enzyme liquid. The cells were not cultivated in a 60 ml plastic culture until the presence of the second generation. The cultivated cells were confirmed as endothelial cells by factor Ⅷ related antigen. The multiplied cells were lined in vitro onto the luminal surface of allogenic vein that was disposed by freeze-drying and radiation. The orthotopic transplantation of autologous venous endothelial cells was performed after the 9-day incubation. Results (9.47±0.35)×106 endothelial cells were obtained after the cultivation. Three hours after cell seeding, the luminal surface of allogenic vein was covered with vast endothelial cells but still had not formed an intact endomembrane. On day 9, the luminal surface was covered with a continuous endothelial monolayer and the arrangement and the shape of the cells all showed the perfect condition of endothelial cells. Eight weeks later, all the transplanted veins kept unobstructed. Conclusion The approach of lining allogenic vein with autologous endothelial cells in vitro may keep the vein unobstructed in the long term.
Objective To discuss the endothelial cell which was modified by exogenous anticoagulant genes contribute to the increase of antithrombosis activity of lined vascular prosthesis and the influence to other physiological functions of endothelial cells. Methods This summarized paper was made on literature review of recent years. Results The transfection of genes, including plasminogen activator (tPA, uPA, Urokinase), thrombomoduline (TM) and hirudin, etc, to endothelial cells resulted in not only the increase of antithrombosis activity of local vascular, but also the decrease of endothelial cell function in adherence and proliferation. Conclusion The increase of antithrombosis activity of lined vascular prosthesis has been done by exogenous genes. However, this technique ought to be studied, intensively.
ObjectiveTo study the early functional change of sinusoid endothelial cell after liver transplantation in rat, and to investigate the endothelia protective effect of prostaglandin E1(PGE1). MethodsRat orthotopic liver transplantation model was performed in “twocuff method”, grouped as follows: group A served as normal rat blank control, group B as operative control with normal donor, group C as experimental control with shock donor, and group D as experimental group with shock donor and PGE1 administration (n=8 in each group). Transplanted groups (referring to recipients without specific definition) were sacrificed 6 h after operation for blood taken to detect serum liver enzymes (ALT, LDH), malondialdehyde (MDA), nitric oxide (NO) and plasm endothelin (ET). Liver tissue was resected at the same time for standard pathologic examination. Comparison of the difference the results was made between groups. ResultsCold preservation time and anhepatic phase were similar in each group, (2±0.5) h and (15±3) min respectively. All survived 6 h after transplantation (8/8) in group B and D with a survival rate of 100%, only 5 survived 6 h after transplantation in group C (5/8) with a survival rate of 62.5%. Comparing with group C, blood ALT, LDH, MDA, ET decreased and NO increased significantly in group D (Plt;0.05). Marked histologic structural damage was observed in group C, while normal light microscope appearance was better preserved in group C and D. ConclusionMarked sinusoid endothelia injury occurs during liver transplantation. Concentration of serum NO and plasm ET well presents its function. PGE1 relieves endothelia injury by improving hemodynamics and stabilizing sinusoid endothelial cell plasma membrane.
Objective To observe the levels of von Willebrand factor ( vWF) expressed by human umbilical vein endothelial cells ( HUVECs) infected by aspergillus fumigatus ( AF) alone or treatment with cytochalasin D, N-cadherin monoclonal antibody, dexamethasone, respectively, so as to explore the mechanism of angioinvasion in invasive aspergillosis. Methods An in vitro model of HUVECs infected by AF hypha was established. The experiment included six groups, ie. a sham control group, a TNF-αgroup, an AF hypha group, a cytochalasin D group, a N-cadherin antibody group, and a dexamethasone group. Cell supernatants were collected to detect the levels of vWF at 2 h, 6 h, 12 h, and 18 h by enzyme linked immunosorbent assay ( ELISA) . Results Compared with that of vWF at 2 h, the level was higher at 18 h in the sham controlgroup and the TNF-αgroup, and higher at 6 h, 12 h, and 18 h in the other groups( P lt; 0. 05) . Compared with the sham control group, the level of vWF in each experiment group increased at 2 h, 6 h, 12 h, and 18 h except that in the N-cadherin antibody group at 2 h ( P lt; 0. 05) . The level of vWF in TNF-α group was higher than that in the AF hypha group at 2 h, but lower at 18 h. ( P lt; 0. 05) . The level of vWF was not significantly different between the cytochalasin D group and the AF hypha group at each time point. The level of vWF was lower in the N-cadherin antibody group than that in the AF hypha group at 2 h and 6 h ( P lt;0. 05) . The level of vWF was not significantly different between the dexamethasone group and the AF hypha group at each time point. Conclusion HUVECs infected by AF hypha overexpress vWF. N-cadherinmonoclonal antibody can reduce the expression of vWF, but cytochalasin D or dexamethasone has no significant effect on it.
Abstract: Objective To investigate the messenger ribonucleic acid (mRNA) expression level of tissue-type plasminogen activator (t-PA) in endothelial cells derived from adult mesenchymal stem cells (MSCs) after fluid shear stress loading which is within the physiological range. Methods After culturing in vitro, bone marrow MSCs of SD rats were seeded on slides.When it come to 80% confluence,26 slides were exposed to 5dyn/cm2 fluid shear stress for 3h in a flow chamber, and then induced to endothelial cells. Among them,13 slides constituted group Ⅰ, and the rest 13 slides set up group Ⅱ, which would be cultured for 3-4d further and passaged in 1∶3. At the same time, control group was set up, which including the cells never exposed to fluid shear stress before the endothelial differentiation. Fluid shear stress were exerting to cells in a specially made flow chamber. The expression level of t-PA mRNA of all groups were measured by real-time fluorescent quantitation reverse transcriptionpolymerase chain reaction (RTPCR). Results After endothelial differentiation for 7 days, the SD rats bone marrow MSCs acquired typical endothelial cell appearance. The t-PA mRNA expression level of group Ⅰ and group Ⅱ have an obviously enhance compared with control group(P＜0.05). The t-PA mRNA expression level of group Ⅱ step down a little (P＞0.05), but it is still significantly higher than that of control group (P＜0.05). Conclusion Fluid shear stress could provide a protective action on the endothelial cells induced from MSCs in vitro, and the effect maintains with the cells passages. This formulates a theoretical foundation to the therapeutics of atherosclerosis and selection of seed cells in vascular tissue engineering.
The autograft and non-autograft cannot meet the needs of clinical vascular surgery. Since there are possibilities of thrombus formation in artificial vascular grafts, the methods for deposing the graft using physical and chemical ways or simply seeding with endothelial cells cannot produce satisfactory grafts for vascular operations until now. In order to increase the anticoagulative capacity of artificial vascular graft, it is rational to use genetic engineering methods modifying the endothelial cells to make it express anticoagulative factors stably. Although seeding artificial graft with the genetically engineered endothelial cells can possibly produce a satisfactory graft for vascular surgery, some problems still need to be solved.
Objective\ To promote the differentiation of cultured endothelial cells and enhance their resistance to fluid shear stress.\ Methods\ Using the mended parallel plate flow apparatus and peristalsis pump providing fluid shear stress, endothelial culture models were established in vitro with the same environment factors as steady culture. According to the increasing degree of shear stress, the experiment included:(1) Group A, exposing to the gradual increasing fluid shear stress, (2) Group B, exposing to step ...
Objective To explore the effect and mechanism of ultrashort wave (USW) for prevention and treatment of vascular crisis after rat tail replantation. Methods Eighty 3-month old female Sprague Dawley rats (weighing 232.8-289.6 g) were randomly divided into 5 groups. In each group, based on the caudal vein and the coccyx was retained, the tail was cut off. The tail artery was ligated in group A; the tail artery was anastomosed in groups B, C, D, and E to establish the tail replantation model. After surgery, the rats of group B were given normal management; the rats of group C were immediately given intraperitoneal injection (3.125 mL/kg) of diluted papaverine hydrochloride injection (1 mg/mL); the rats of groups D and E were immediately given the local USW treatment (once a day) at anastomotic site for 5 days at the dosage of 3 files and 50 mA for 20 minutes (group D) and 2 files and 28 mA for 20 minutes (group E). The survival rate of the rat tails was observed for 10 days after the tail replantation. The tail skin temperature difference between proximal and distal anastomosis was measured at pre- and post-operation; the change between postoperative and preoperative temperature difference was calculated. The blood plasma specimens were collected from the inner canthus before operation and from the tip of the tail at 8 hours after operation to measure the content of nitric oxide (NO). Results The survival rates of the rat tails were 0 (0/14), 36.4% (8/22), 57.1% (8/14), 22.2% (4/18), and 75.0% (9/12) in groups A, B, C, D, and E, respectively, showing significant overall differences among 5 groups (χ2=19.935, P=0.001); the survival rate of group E was significantly higher than that of group B at 7 days (P lt; 0.05), but no significant difference was found between the other groups by pairwise comparison (P gt; 0.05). At preoperation, there was no significant difference in tail skin temperature difference among 5 groups (P gt; 0.05); at 8 hours, 5 days, 6 days, and 7 days after operation, significant overall difference was found in the change of the skin temperature difference among groups (P lt; 0.05); pairwise comparison showed significant differences after operation (P lt; 0.05): group B gt; group D at 8 hours, group C gt; group D at 5 days, groups A, B, and C gt; group D at 6 days, groups B and C gt; groups A and E, and group B gt; group D at 7 days; but no significant difference was found between the other groups at the other time points (P gt; 0.05). Preoperative plasma NO content between each group had no significant difference (P gt; 0.05). The overall differences had significance in the NO content at postopoerative 8 hours and in the change of the NO content at pre- and post-operation among groups (P lt; 0.05). Significant differences were found by pairwise comparison (P lt; 0.05): group D gt; groups A, B, and C in the plasma NO content, group D gt; groups A and B in the change of the NO content at pre- and post-operation; but no significant difference was found between the other groups by pairwise comparison (P gt; 0.05). Conclusion Rat tail replantation model in this experiment is feasible. USW therapy can increase the survival rate of replanted rat tails, reduce skin temperature at 7 days, improve blood supply, increase the content of nitric oxide at the early period and prevent vascular crisis.
Objective To evaluate which is better method zymogen or low temperature frozen in removing vascular endothelial cell so as to lay a foundation for creating a kind of brace which is not to be rejected and the same as own blood vessel. Methods Fresh and not damaged umbilical blood vessel was collected from natural labour women, human umbilical blood vessel was remove carefully from normal foetus, then was put into disinfectant at 37℃ for 24 hours. They were divided into 3 groups:normal group(NG),zymogen group(ZG) and low temperature frozen group(LG). ZG: 0.1% collagenⅡ enzyme was addedin umbilical blood vessel and closed the both sides and the vascular endothelialcell was removed in 37℃ water. LG:Umbilical blood vessel was put into liquidnitrogen for 24 hours after frozened step by step, and then it was put into 37℃ water for 30-60 s and the vascular endothelial cells were washed away by normal saline. NG:Umbilical blood vessel was kept into 4℃ Kerb’s liquid. The bacteria were culturedin each group. The samples were stained by HE,elastic fiber and collagen fiberwere observed by light and scanning electron microscope. The difference of compliance was compared. Human leukocyte antigen ABC(HLA-ABC) and HLA-DR were observed by immunohistochemical method and the expression of antigen of umbilical blood vessel was analysed. Results In LG, umbilical vascular endothelial cells were removed completely; artery showed vertical smooth muscle and vein showed elastic membrane. InZG, umbilical vascular endothelial cells were removed completely after 20 minutes;artery showed vertical smooth muscle cells and vein showed lower endothelial layer. The vascular compliance in LG was higher than that in NG, and the latter was also higher than that in ZG,but showing no significant differences (Pgt;0.05). The compliance of umbilical vein was 2-3 times as much asthat of umbilical artery.The expression of HLA-ABC and HLA-DR in LG andZG were lower than that in NG, showing significant differences (Plt;0.01). Conclusion Low temperature frozen methodand zymogen method(0.1% collagen Ⅱ enzyme for 20 min) can remove vascular endothelial cells of human umbilical blood vessel completely.Low temperature frozenmethod was better than zymogen method.
Objective To explore an optional condition to induce mouse embryonic stem cell(ESC) to differentiate into endothelial cells so as to provide seedcells for tissue engineered vascular. Methods The embryos from one pregnant 12.5days mouse was harvested to culture the mouse embryonic fibroblasts(MEF). The ESC was reanimated by common method, and used to cultured into embryoid body(EB) in vitro. The EB which was used to induce into endothelial cells was divided into two groups. The EB was cultured in the EB medium with 3ng/ml transforming growth factor β1, 50 ng/ml vascular endothelial cell growth factor and 1 μmol/L potent and selective inhibitor of activin receptorlike kinase receptors in experimental group. The EB was cultured in the EB medium in the control group. After 14 days, RTPCR and immunohistochemistry were used to detect vWF and CD34, to analyze the morphology and type of the differentiated cells fromESC. Results The primary MEF had a high proliferation activity. At the 3rdday, the fusion rate of MEF was about 90% with a fusiform shape. The cells was fusiform shape and arranged compactly with fullness of nucleus and 2-3 entoblasts. The 3rd5th generations EB was polygonal with fullness of cytoplasm and 3-4 entoblasts. ESC could maintain undifferentiated state, and the cells unit lookedlike bird nest with smooth margin; the cells was small at size and b refractivity with high rate of nuclein and rapid proliferation. At 3 days of dropculture, EB can seen grossly and at 3 days of suspension, large and transparent EBformed. EB was spread radiately with an intensive adhesion at the 2nd day. In experimental group, many round cells was differentiated around EB from the 4thday to the 7th day, and form tubular structures from the 10th day to the 14th day. The vWF and CD34 were expressed. In control group, EB could not form tubularstructures, and the vWF and CD34 were not expressed. Conclusion ESC can differentiate into endothelial cells under some conditions, and form vessellike structure under condition culture, which can provide sources of seed cells for tissue engineered vessel.