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 review the latest research progress on keratinocyte growth factor (KGF), to thoroughlyunderstand its basic characteristics and appl ication methods and to lay a sol id foundation for the research and development of new KGF medicines and improving the qual ity of skin substitutes. Methods Domestical and international l iteratures on KGFin recent years were extensively reviewed and analyzed. Results KGF was secreted by mesenchymal cells and its receptors were distributed in epithel ium to promote the prol iferation, migration and differentiation of epithel ial cell specifically, which closely related to the organ development, wound heal ing, tumorigenesis and immune reconstruction. Conclusion KGF can be used to improve wound heal ing and the performance of skin substitutes. However, the structure of KGF needs to be changed to el iminate its side effects and purify its promoting effect on epithel ial cell growth.
Objective To construct a mammalian expression vector ofbasic fibroblast growth factor (bFGF) and to investigate the expression of bFGFin vitro and in vivo. Methods A mammalian expression vector pcDNA3.1/myc-His(-)C-bFGF was constructed with gene cloning technique. The mammalian expression system was prepared and purified. The expression of bFGF cDNAin cultured transfected cells was examined by RT-PCR and cell immunohistochemistry. The recombinant plasmids, pcDNA3.1/myc-His(-)C-bFGF and pCD2-VEGF121, were transferred into rabbit cervical muscle by direct injection of plasmid following electric pulses in vivo. The transferred gene expression and the biological effect were measured by use of histochemistry and immunohistochemistry analysis. Results The eukaryon expression system pcDNA3.1/myc-His(-)C-bFGF could express the target protein bFGF in vitro. The recombinant plasmids, pcDNA3.1/myc-His(-)C-bFGF and pCD2-VEGF121 were transferred into muscles flap in vivo successfully. The active proteins bFGF and VEGF121were expressed at high levels. Blood vessels increased significantly in the muscles, and blood circulation was improved by local angiogenesis. Conclusion Theeukaryon expression vector of bFGF is constructed and can be expressed successfully in vitro and in vivo. That is a primary preparation for the research on tissue transplantation and tissue engineering with bFGF gene therapy.
OBJECTIVE To study the early protective effects of basic fibroblast growth factor(bFGF) on the experimental acute spinal cord injury. METHODS Thirty-four SD rats were randomly divided into three groups, and were subjected to contusion of thoracolumbar spinal cord. A thin plastic tube was placed in subarachnoid space below the injury level for perfusion. The bFGF-treated rats were received 20 microliters bFGF(containing bFGF 100 U) at once, 30 min, 1, 2, 3, 4, 6, 12, 24 and 48 hours after injury, and an equal volume of normal saline was given to the control group at the same time. The injured spinal cord was detected by morphological observation and biochemical index after injury. RESULTS The degree of ionic disorder in bFGF-treated rats was significantly ameliorated and the contents of H2O were also markedly decreased. The morphological finding showed that the damages of gray and white matter in bFGF-treated rats were slighter than those of saline-treated rats. CONCLUSION bFGF has some protective effects on the secondary lesion of early spinal cord injury in rats.
Objective To establish the three diamension-model and to observe the contribution of endothelial progenitor cell (EPC) in the angiogenesis and its biological features. MethodsEPC was obtained from the rats’ peripheral blood. Its cultivation and amplification in vitro were observed, and the function of the cultural EPC in vitro was detected. The three diamension-model was established and analyzed. ResultsEPC was obtained from the peripheral blood successfully. The proliferation of the EPC which induced with VEGF(experimental group) was better than that without VEGF （control group） at every different phase (P＜0.01). It was found that EPC grew into collagen-material from up and down in the three diamension-model, and its pullulation and infiltration into the collagen were seen on day 1 after cultivation. With the time flying, there were branch-like constructions which were vertical to the undersurface of collagen and interlaced to net each other. It showed that in experimental group the EPC grew fast, its infiltration and pullulation also were fast, the branch-like construction was thick. But in control group, the EPC grew slowly, infiltration and pullulation were slow, the branch-like construction was tiny and the depth of infiltration into collagen was superficial. The number of new vessels in experimental group was larger than that in the control group at every different phase (P＜0.01). ConclusionRat tail collagen can induce EPC involved in immigration, proliferation and pullulation in angiogenesis. The three-diamension model of EPC can be used to angiogenesis research. VEGF can mobilize and induce EPC to promote the angiogenesis.
Porpose To investigate the optimal concentration of epidermal growth factor (EGF) and basic fibroblast growth factor (bFGF) on DNA synthesis and their synergism indensity arrested human retinal pigment epithelial (RPE) cells. Methods Growth factor effects in cultured human RPE of the 6th generation were assessed by [3 H]-thymidine incorporation and radioautography. Results EGF and bFGF were potent stimulators when used alone,and their optimal concentrations were 10ng/ml in DMEM and 1ng/ml in 2% serum DMEM.When used in combination (10ng/ml EGF and 10ng/ml bFGF),they caused a significant enhancement of [3 H]-thymidine incorporation about 2.96 times. Conclusion EGF and bFGF were potent stimulators in RPE cells,and demonstrated synergism in their action. (Chin J Ocul Fundus Dis,1998,14:98-100)
Objective To evaluate the ability of inductive osteogenesis of allgraft demineralized bone containing basic fibroblast growth factor (bFGF/ALB) in repairing bone defect. Methods Thirty-two New Zealand white rabbits were randomly divided into four groups (groups A,B,C and D, n=8). A segmental bone defect of15 mm inlength was made on the bilateral radius respectively and the defects filled with ALB/bFGF in group A, with ALB in group B, with bFGF in group C and without any materials in group D serving as blank control. At 2, 4, 6 and 8 weeks after operation, all restored bones were evaluated by roentgenography, histological observation and Ca2+detection of osteotylus. Results The X-ray films showed that groups A and B had a little shadow of bone formation at 2 weeks, while groups C and D had transparent shadow; that group A had denser shadow and new bone formation at 4 weeks and 6 weeks, groups B and C had a little increase of shadow and group D had little shadow at fractured ends; and that group A had formation of bone bridge at 8 weeks, the new formed bone in fractured ends of group B closed with each other, the gap still existed in group C, and the defects filled with the soft tissue in group D. The Ca2+content of group A was higher than that of groups B, C and D at 4 weeks (Plt;0.05) and 8 weeks (Plt;0.01). The histological observaton showed that the degree of bone restoration of group A was superior to that of groups B, C and D. Conclusion bFGF/ALB is a good material to improve bone restoration.
To harvest human keratinocyte growth factor (KGF) mimic peptides with Ph.D.-7TM phage display peptide l ibrary. Methods Ph.D.-7TM phage display peptide l ibrary was biopanned for 4 rounds to harvest monoclonal anti-body human KGF and then phage tilter was detected. ELISA detection was performed to detect the binding force of random-selected monoclonal phages, thereafter DNA extracted from phages with better binding activity was sequenced and the Basic BLAST system was appl ied to conduct the sequence similarity and homology analysis. Results After 4 rounds ofbiopanning, the titer of phages was increased gradually and the enrichment of specific phage mimic peptides was obtained. The titers of monoclonal phages were up to 2.0 × 1014 pfu/mL according to ELISA detection. According to the absorbance value, the monoclonal phages with better binding activities to certain specific antibodies were sequenced, and 26 base sequences related to the promotion of division and growth were verified, 2 of which were similar to human KGF. Homology sequence analysis revealed that the common sequence of those 26 base sequences was similar to the partial sequences of human KGF. Conclusion The phage mimic peptides resembl ing or related to human KGF DNA can be harvested from Ph.D.-7TM phage display peptide l ibrary, which may be conducive to improve human KGF performance, wound heal ing and the qual ity of tissue engineered skin substitutes.
ObjectiveTo investigate the expression of keratinocyte growth factor (KGF) and cyclooxygen-ase-2 (COX-2) protein and microvessel density (MVD), and to explore their function and mechanism in the multistep process of gastric cancer. MethodsThe expressions of KGF and COX-2 protein in 64 samples of gastric cancer and 30 cases of normal gastric mucosa tissues were detected by immunohistochemistry. The MVD was detected by staining the endothelial cells in microvessles using anti-CD34 antibody. ResultsThe positive rate of KGF and COX-2 protein expression in gastric cancer were 65.6% (42/64) and 79.7% (51/64), respectively, which was significantly higher than that in normal gastric mucosa tissues 〔(23.3%, 7/30), P=0.046; (13.3%, 4/30), P=0.008〕. The MVD of gastric cancer was 31.8±8.0, which was significantly higher than that of normal gastric mucosa tissues (14.3±6.1), P=0.000. The MVD in gastric cancer with coexpressive KGF and COX-2 protein was 35.9±5.7, which was significant higher than that with non-coexpressive KGF and COX-2 protein (25.7±7.0), P=0.000. Both the expression of KGF and COX-2 protein were related to the invasion of serosa, lymph node metastasis and TNM staging (Plt;0.05, Plt;0.01). The MVD of gastric cancer tissues was related to lymph node metastasis and TNM staging (Plt;0.05), but unrelated to patient’s age, gender, and differentiation of tumor (Pgt;0.05). The co-expression of KGF and COX-2 protein was frequently found in patients with deeper invasion of serosa, lymph node metastasis, and higher TNM staging (Plt;0.05), but which was not associated withpatient’sage, gender, and differentiation of tumor (Pgt;0.05). The expression of KGF protein was positively correlated to the expression of COX-2 protein (r=0.610, P=0.000). There was positive correlation between MVD and the expression of KGF (r=0.675, P=0.000) and COX-2 protein (r=0.657, P=0.000) in gastric cancer, respectively. ConclusionKGF and COX-2 highly expressed by gastric cancer, which may be involved in the invasion and metastasis of gastric cancer by synergisticly promoting the angiogenesis.