Objective To investigate the effect of hepatocyte growth factor (HGF) on the barrier function of retinal peigment epithelium (RPE) and to detect the pathological mechanism of retinal detachment (RD) induced by over expression of HGF in RPE. Methods Sub-retina injection of E1/E3deleted adenoviral vectors encoding HGF (Ad CMV.HGF) and green fluorescent protein (Ad CMV.GFP) in adult pigmented rabbits [5times;104 plaque-forming units (pfu)/eye] to set up the model of retinal detachment. The ocular fundus and pathological changes were observed 3, 7, 14, and 28 days after injection. The expression level of HGF in retina and vitreous body was detected by immunohistochemistry and enzyme linked immunosorbent assay (ELISA). Results In the control eyes injected with AdCMV.GFP, expression of GFP only detected in RPE monolayer. The eyes injected with AdCMV.HGF had b HGF immune positive action in RPE cells at the injection site. The expression level of HGF in vitreous body reached the peak 7 days after injection and decreased to the basic level 28 days after injection. Chronic RD and chronic choroidal inflammation were found in the eyes injected with AdCMV.HGF within the time frame of HGF expression. Proliferative RPE cells were found in subretinal space in the region of RD, and multilayered cellular membranes developed in some eyes. Conclusion Over expression of HGF in RPE may induce chronic serous RD with subretinal proliferation of RPE, which suggests that HGF should be further studied as a target for therapeutic intervention in RD. (Chin J Ocul Fundus Dis, 2007, 23: 193-197)
Objective To investigate the feasibility of differentiating human umbilical cord blood stem cells into hepatocytes. Methods Thirty-six BALB/c nude mice were randomly divided into experimental group and control group(18 in each of the group), and experimental group was again randomly divided into group A， B and C (six in each of the group). The mice in experimental group and control group were exposed to 350 cGy radiation produced by 60Ｃｏ. After 3 h, karyocytes at different concentrations in the fresh human umbilical cord blood were injected into the mice in experimental group A, B, C via their tail veins, and the equal volume of normal sodium (NS) was also injected into control group via tail veins. After one month, carbon tetrachloride (CCl4) was injected into experimental group A, B and control group via abdominal cavity, and the equal volume of normal sodium was injected into experimental group C. After two months, immunohistochemistry and reverse transcriptase polymerase chain reaction (RT-PCR) were used to detect the expressions of human cytokeratin-18 (CK18), cytokeratin-19 (CK19) and albumin (ALB) in liver tissues of all mice. Results The expressions of CK18, CK19 and ALB in injured liver tissues were all positive, and the expressions of experimental group B were higher than those of experimental group A （P＜0.05）, but the expressions of CK18, CK19 and ALB in the liver tissues of control group and experimental group C, whose were not injured with CCl4, were all negative. Conclusion Human umbilical cord blood-derived stem cells can differentiate into hepatocytes and express ALB under special microenvironment after liver injured by CCl4 , and the expression level of ALB maybe directly related to the number of human umbilical cord blood stem cells.
To investigate the effect of hepatocyte growth factor (HGF) on prol iferation of cultured human eccrine sweat gland epithel ial cells (hESGc) and the involvement of phosphorylation of ERK1/2. Methods hESGc were cultured in keratinocyte serum free medium (KSFM) and the first generation of hESGc was harvested. The expression of C-met was detected by immunocytochemistry. MTT assay was used to detect the effect of HGF on the prol iferation of hESGc. The cells were divided into blank group, control group and experimental group. The culture density was 2 × 103 cells/hole in control group and experimental group. Two hundred μL KSFM with HGF in different levels was added to every hole. hESGcwere cultured in KSFM with HGF at different levels (2, 20, 40 and 80 ng/mL) in experimental group, in KSFM without HGF incontrol group, and in KSFM without HGF and no hESGc in blank group. The cell prol iferation was observed in xperimental group 2 and 4 days later. Western blot was used to detect the expression of phosphorylated ERK1/2 at 40 ng/mL HGF after 0, 5, 30, 90 and 120 minutes. Results The results were positive for anti-C-met staining in the cytoplasm. HGF (40 ng/mL and 80 ng/mL) significantly improved the prol iferation of hESGc (P lt; 0.05). When cultured in the KSFM with 40 ng/mL HGF, the cell prol iferation rate and the absorbance were 74.2%, 0.239 3 ± 0.070 9 at 2 days and 74.8%, 0.287 8 ± 0.074 3 at 4 days; showing significant differences when compared with control group (P lt; 0.05). When cultured in KSFM with 80 ng/mL HGF, the cell prol iferation rate and the absorbance were 54.5%, 0.212 3 ± 0.059 2 at 2 days and 40.3%, 0.231 0 ± 0.056 7 at 4 days; showing significant differences when compared with control group (P lt; 0.05). The expression of p-ERK1/2 reached to the maximum after stimulation of 40 ng/mL HGF for 5 minutes, and relative integral absorbance (RIA) was 0.593 2 ± 0.192 2, increased 8.1 times compared with instant stimulation (P lt; 0.01). Conclusion HGF could induce the prol iferation of hESGc and activate the phosphorylation of ERK1/2 protein.
【Abstract】Objective To investigate the injury of calcium on the liver. Methods By using collagenase-containing solution to perfuse the rat livers, the rat liver suspension with different viability was prepared, preserved hypothermically, and the cytosolic calcium comcentration was detected with Fura2/AM. Results ① The concentration of cytosolic calcium after 2-hour storage: Experiment group 1(viability 5%) (1055.0±30.79) nmol/L, experiment group 2(viability 10%) (853.0±20.42) nmol/L, experiment group 3(viability 30%) (616.0±13.20) nmol/L, experiment group 4(viability 50%) (562.0 ±26.06) nmol/L, experiment group 5(viability 70%-80%) (318.0±13.01) nmol/L, experiment group 6(viability 90%) (114.6±6.11) nmol/L. ②The concentration of cytosolic calcium after 24hour storage: Experiment group A(viability 10%) (1704.0±70.11) nmol/L, experiment group B(viability 50%) (1125.0±23.22) nmol/L. The results showed that the lower was the viability, the higher was the cytosolic calcium concentration.With the same viability the cytosolic calcium concentration elevated more than two times higher than the original concentration with the time lengthened. Conclusion Calcium overload is one of the main factors which attribute to the ischemiareperfusion injury of the hepatocytes.
Objective To study the effects of hepatocyte growth factor (HGF) and receptor c-met on the development of primary breast carcinoma, and the relationship between it and prognosis. Methods The study of HGF and c-met related to breast carcinoma was reviewed by history document and experimental study in recent years. Results HGF is a growth factor which has mitogenic, migrating, invasive and angiogenic activities in breast carcinoma cells. The carcinogenic mechanism of breast carcinoma was more clear with the discovery of the relationship between HGF and its receptor c-met. Conclusion The HGF/c-met plays an important role in the generation and progress of breast carcinoma. Studying the effects of HGF/cmet on breast carcinoma is significant in guiding clinical treatment.
Objective To investigate the effects of human recombinant hepatocyte growth factor(rh-HGF) on the expression of c-Met in intima of allograft vessels after cardiac transplantation in rats. Methods Heterotopic heart transplantation were established in abdominal cavity with eighty Wistar rats and forty SD rats. Donors’ cardiac grafts from Wistar rats were transplanted to SD rats(allograft) or Wistar rats(isograft).Sixty recipient rats were divided into three groups, control group：20 Wistar rats were injected with normal saline 1ml/kg·d intraperitoneally after transplantation; cyclosporine A (CsA) group:20 SD rats were injected with CsA 5mg/kg·d intraperitoneally on operation day; rhHGF group:20 SD rats were injected with rh-HGF 500μg/kg·d and CsA 5mg/kg·d intraperitoneally on operation day. The cardiac grafts were harvested at the 15th day and 60th day after transplantation. The crosssection of vascular tissues were used for immunohistochemistrical staining of c-Met, and investigated the expression of c-Met messenger ribonucleic acid (mRNA ) in intima of allograft vessels by reverse transcriptionpolymerase chain reaction(RT-PCR). The pathologic changes of allograft coronary vessels were observed with histopathological method. Results The allograft coronary arteries showed minimal intimal thickening, the endothelium and internal elastic lamina remained almost intact in rh-HGF group after transplantation.The expression of c-Met and c-Met mRNA in intima of allograft vessels after transplantation in rhHGF group were significantly higher than those in CsA group and control group（expression of c-Met at 60d: 1.85±0.26 vs. 0.96±0.10, t=8.491,P=0.000;1.85±0.26 vs. 0.58±0.03, t=13.725,P=0.000; expression of c-Met mRNA at 60d: 192±0.22 vs. 0.88±0.07, t=11.940,P=0.000;1.92±0.22 vs. 0.42±0.02,t=19.206,P=0.000）. Conclusion rh-HGF may prevent the progression of cardiac allograft vasculopathy through upregulating the expression of c-Met to stimulate endothelial cell repair and growth.
Objective To investigate the application and advancement of hepatocyte t ransplantation ( HCT) .Methods Literatures about the advancement of HCT were reviewed and analyzed. Results There have been manynovel technologies and advancement s in the application of HCT. For example , gene modified cell can be used as seedcell , subcutaneous t ransplantation can be taken when combined with giant molecule material and the encap sulationpreconditioning technique can also carried before operation to improve the rate of survival. Conclusion With moreand deeper understanding of hepatocyte t ransplantation and the development of advanced techniques such as the application of giant molecule , HCT will be extensively used in the clinical t reatment of acute and chronic hepatic diseases.
Objective To evaluate the transfection efficiency and expression level of hepatocyte growth factor (HGF) by transfecting a recombinant adenovirus carrying HGF gene (Ad-HGF) into bone marrow mesenchymal stem cells (BMSCs) and to explore the effect of the expression supernatant on BMSCs in vitro so as to lay a foundation for the manufacture of gene medicine which expresses efficient cell factors. Methods Rat BMSCs were isolated using Percoll density gradient method and cultured according to the adherent property of BMSCs. The expression of c-Met was detected by immunohistochemical examination. BMSCs were infected with a recombinant adenovirus carrying green fluorescent protein gene (Ad-GFP) at multipl icity of infection (MOI, 0, 25, 50, 100, and 200 pfu/cell). To select an optimal MOI, the transfection efficiency and the degree of cell damage were assayed by flow cytometry and MTT, respectively, at 48 hours after transfecting. The expression of HGF in BMSCs transfected with optimal MOI Ad-HGF was measured with ELISA assay. MTT method was used to evaluate the prol iferation effect of HGF expression supernatant on BMSCs. Results Immunohistochemical staining showed that BMSCs expressed c-Met receptor for HGF. At 48 hours after transfecting with different MOI Ad-GFP (0, 25, 50, 100, and 200 pfu/cell), the transfection efficiencies were 0.34% ± 0.04%, 40.72% ± 0.81%, 61.72% ± 1.04%, 85.33% ± 0.83%, and 17.91% ± 0.63%, respectively; and the highest transfection efficiency was observed at 100 pfu/cell MOI. The cell damage was obviously observed when MOI was 200 pfu/cell. The expression of HGF in BMSCs reached the highest level after being transfected with 100 pfu/cell MOI Ad-HGF for 48 hours. The expression product could stimulate the prol iferation of BMSCs. The prol iferation of BMSCs gradually rose with the increase of HGF protein, and reached the highest level at 10% (320 pg). Conclusion BMSCs can be transfected efficiently with Ad-HGF and express HGF protein, which stimulates the prol iferation of BMSCs. It suggests that BMSCs is an ideal repair cells with gene vector.
【Abstract】 Objective To observe the effect of cytokines and combinations in the inducement of human umbil icalcord blood-derived CD34+ cells into hepatocyte-l ike cells. Methods The mononuclear cells (MNCs) were derived by density gradient centrifugation and the CD34+ cells were sperated from MNCs. The human umbil ical cord blood-derived CD34+ cells were cultivated through 49 different combinations of cytokines including leukemia inhibitor factor (LIF), oncostatin M, bFGF, aFGF, hepatocyte growth factor, EGF and stem cell factor for 28 days, and the concentrations of the cytokines were 10, 10, 10, 10, 20, 20 and 50 ng/mL, respectively. The mRNAs of cytokeratin 19 (CK-19), CK-18, glutamine synthetase (GS), human albumin (ALB) and α-fetoprotein (AFP) were detected every seven days. The ALB secretion abil ity, detoxification abil ity and hepatin synthesis abil ity of the induced cells were detected by immunofluorescence assay, indocyanine green (ICG) and periodic acid-schiff assay, respectively. The fresh umbil ical cord blood-derived CD34+ cells were detected at the same time as a control. Results The mRNAs of CK-19, CK-18 and GS could be transcribed in all the induced cells, but the transcription of the mRNAs of ALB and AFP which was the special mark of mature hepatocyte and l iver stem cell, respectively, was not found. All the mRNAs could not be found in freshly isolated umbil ical cord blood-derived CD34+ cells. All the cells induced in vitro could not release ALB, and not help the detoxification of ICG which was the fundamental function of mature l iver cells. These results were the same in the control group. The hepatin synthesis abil ity of all the induced cells increased by comparison to the fresh ones. Conclusion Though some mRNAs of proteins which are transcribed in hepatocytes can be found in the induced cells, umbil ical cord blood-derived CD34+ cells could not be transdifferentiated into hepatocyte-l ike cells through cytokines in vitro.
【Abstract】ObjectiveTo establish an efficient, effective hepatocyte isolation technique in order to increase cell production and decrease the prime cost. Methods The inferior vena cava below diaphragm was dissected and ligatured, and the inferior vena cava below liver was separated. Subsequently, the liver was perfused with EGTA through the portal vein while the inferior vena cava below liver was opened, and then the liver was harvested. The liver tissue was cut into 1 mm×1 mm×1 mm and digested at 37 ℃ water bath with Ⅳ collagenase for 30-40 minutes, then the hepatocytes were purified and cultured in CO2 incubator. The production and function of hepatocytes were assessed. ResultsThe isolated hepatocytes using this technique were more than 95% among the all isolated cells. No statistic difference was found in cell production and cell function comparing with traditional technique. But this technique was simplified and more economically. ConclusionThis modified hepatocyte isolation technique is efficient and effective. It can ensure the amount of production and purity of hepatocytes.