Objective To investigate the effects of the insulin-like growth factor 1 (IGF-1), the transforming growth factor β1(TGFβ1), and the basic fibroblast growth factor (bFGF) on proliferation and cell phenotype of the human fetal meniscal cells, and to find out the best combination and concentration of the growth factors for the meniscus tissue engineering. Methods The fetus came from the healthy woman accidental abortion and the procedure had got her approval.The human fetal meniscal fibrochondrocytes were cultured in vitro. The cell phenotype was identifiedby the collagen type Ⅱ immunohistochemistry and Aggrecan immunofluorescence. Inthe growth factor groups, the 3rd passage meniscal cells synchronized by the serum starvation method and were mixed with IGF-1 (1, 10, 50, 100 μg/L), TGF-β1 (0.1, 1.0, 5.0, 10.0, 50.0 μg/L), and bFGF (5, 10, 50, 100, 200 μg/L), respectively, and in the combination groups, the combinations of bFGF and TGF-β1, bFGF and IGF-1, TGF-β1 and IGF-1 were established at their optimal effect concentrations. The control group was also established for comparison. The dose-response relationship was studied at 48 h and 72 h bythe MTT colorimetric method. Results The 3rd passage meniscalcells could express collagen type Ⅱ and Aggrecan before and after the addition of the three growth factors. The proliferating effects of the growth factors (IGF-1 50 μg/L，TGF-β1 5 μg/L，bFGF 50 μg/L) on the 3rd passage cells at 48 h and 72 h were significantly better in the growth factor groups than in the control group (Plt;0.05)，and the combination groups of bFGF 50 μg/L and IGF-1 50 μg/L, IGF-1 50 μg/L and TGF-β1 5 μg/L showed a significantly higher proliferatingeffect than that in the single growth factor group (Plt;0.05). bFGF 50 μg/L and TGF-β1 5 μg/L had no synergetic effect (Pgt;0.05). Conclusion IGF-1, TGF-β1 and bFGF can promote the proliferation of the human fetal meniscal cells, respectively, and the combinations of bFGF and IGF-1, IGF-1 and TGF-β1 at their optimal concentrations can have better proliferating effects than the single growth factor. They can be used for the in vitro amplification of the meniscal seed cells.
Objective To construct the recombinant adenovirus bearing human transforming growth factor β1(TGF-β1) and bone morphogenetic protein 7 (BMP-7) genes, and investigate its co-expression in the marrow stromalstemcells (MSCs) and bioactivity effect. Methods Using the replication defective adenovirus AdEasy as a carrier, MSCs were infected by the high-titer-level recombinant adenovirus taking TGF-β1 and BMP-7 genes. Immunocytochemistry, in situ hybridization，reverse transcription-polymerase chain reaction (RT-PCR), and hexuronic acid level test were used to detect the coexpression of the exogenous genes and to analyze their effect transfection on directive differentiation of MSCs. Results The immunocytochemistry staining showed that the brown coarse grains were situated in the cytoplasm of the most MSCs 72 h after infection. Procollagen ⅡmRNA in the cells was detected by the in situ hybridization, and the content of hexuronic acid in the culture mediumwas significantly increased 10 days after infection compared with the level before infecton (Plt;0.01). Conclusion The recombinant adenovirus bearing human TGF-β1 and BMP-7 genes can be constructed, and the exogenous gene can be coexpressed in MSCs, which may offer a novel approach to thelocal combination gene therapy for repairing joint cartilage defects.
Objective To study the relation between expressions of transforming growth factor β1 （TGF-β1）, transforming growth factor receptor type Ⅰ (TβRⅠ) and cell proliferation, cell cycle in gallbladder carcinomas, to disclose the mechanism of TGF-β1 and TβRⅠin the gallbladder carcinogenesis，and to evaluate their values in the prognosis of gallbladder carcinomas. Methods Thirty five gallbladder carcinomas 〔age （57.94± 4.61） years, 14 male cases and 21 female cases〕 comprised 32 adenocarcinomas, 2 adenosquamous carcinoma and 1 squamous cell carcinomas. Formalin fixed, paraffin embedded sections from gallbladder carcinomas were immunostained with TGF-β1, TβRⅠ, PCNA, cyclin E antibodies by immunochemical assays. Gallbladder adenoma and chronic cholecystitis were collected as non-malignant controls. Patients of gallbladder carcinomas were followed up. Results Positive immunostaining rate of TGF-β1 was 57.14% in gallbladder carcinomas, which was significantly higher than that in gallbladder adenomas and chronic cholecystitis (P＜0.01, respectively). Expression of TGF-β1 was associated with Nevin stage, lymph nodes and distant metastasis (P＜0.05, P＜0.01, respectively). Expression of TGF-β1 was positively correlated with expression of PCNA LI and cyclin E (r=0.523 2, P=0.001 3; r=0.406 5, P=0.015 4), and 34.29% of gallbladder carcinomas were immunostained positively for TβRⅠ. Expression of TβRⅠwas significantly lower in gallbladder carcinomas than that in gallbladder adenomas and cholecystitis (P＜0.05, respectively). It was significantly lower in gallbladder carcinomas patients with lymph nodes and distant metastases than in those without (P＜0.05). Expression of TβRⅠwas negatively correlated with PCNA LI (r=-0.402 4, P=0.016 6). Patients with negative expression of TGF-β1 and/or positive expression of TβRⅠ had significant longer survival rates than those with positive expression of TGF-β1 and/or negative expression of TβRⅠ(P＜0.01, P＜0.05, respectively). Expressions of TGF-β1 and TβRⅠ correlated with prognosis of gallbladder carcinomas closely. Conclusion TGF-β1 and TβRⅠ have close correlation with cell proliferation, cell cycle of gallbladder carcinomas and are important biological markers of carcinogenesis and progress of gallbladder carcinomas. The escape of growth inhibition of TGF-β1 due to low expression of TβRⅠand carcinogenesis of TGF-β1 may play an important role in gallbladder carcinogenesis. TGF-β1 and TβRⅠare valuable indices for judging the prognosis of gallbladder carcinoma.
OBJECTIVE: To investigate the mechanism of overhealing alleviation by salvia miltiorrhiza (SM) in wound healing. METHODS: Fibroblasts were cultured in vitro, and SM was applied with different concentrations (40, 80, 160 and 320 micrograms/ml) and time(the 1st, 2nd, 3rd, 4th and 5th days) to influence their autocrine. The levels of transforming growth factor-β1 (TGF-β1) and epidermal growth factor (EGF) were determined by ELIAS and radioimmunoassay respectively. RESULTS: The SM could inhibit autocrine of TGF-β1 by fibroblasts (P lt; 0.05). However, it did not affect autocrine of EGF (P gt; 0.05). CONCLUSION: The above results indicate that SM reduces overhealing by inhibiting the autocrine of TGF-β1 selectively.
Objective To determine whether the transforminggrowth factor β1 (TGF-β1) is a key regulatory molecule required for an increase or a balance of extracellular matrix (ECM) and DNA synthesis in the goat passaged nucleus pulposus (NP) cells. Methods The NP cells isolated from the goat intervertebral discs were cultured in vitro for a serial of passages and transfected with the replicationincompetent adenoviral vectors carrying the human TGF-β1 (hTGF-β1) or lacZ genes. Then, they were cultured in monolayer or alginate bead 3dimensional (3-D) systems for 10 days.The changes in the production and the molecular components of ECM that occurredin the NP cells transfected with Ad/hTGF-β1 or the controls were evaluated by Westernblot and absorbance of glycosaminoglycan (GAG)-Alcian Blue complexes. Differences of DNA synthesis in the variant cells and culture systems were assessed by fluorometric analysis of the DNA content. ResultsA quantitation in the variant culture systems indicated that in monolayers the NP cells at Passage 3 transfected with Ad/hTGF-β1 had a much higher cell viability and more DNA synthesis(P＜0.05); however, in the alginate 3-D culture system, the NP cells transfected with Ad/hTGF-β1 did not have any significant difference from the controls(P＞0.05). The Western blotting analysis ofthe protein sample isolated from the variant cells for TGF-β1, type Ⅱ collagen, and Aggrecan expression indicated that in the monolayers and alginate 3-D culture systems the NP cells at Passage 3 transfected with Ad/hTGF-β1 revealed much higher protein levels than the controls(P＜0.05)； whereas the type Ⅰcollagen content was much lower than the controls (P＜0.05), but a significatly increased ratio of type Ⅱ/type Ⅰ collagen was found in both of the cell culture systems(P＜0.05). The GAG quantification also showed a positive result in both the cell culture systems and the NP cells at Passage 3 transfected with Ad/hTGF-β1 had a much higher GAG content than the controls(P＜0.05). Conclusion To a greaterextent, hTGF-β1 can play a key role in maintaining the phenotype of the NP cells and can still have an effect of the phenotypic modulation after a serial of the cell passages. The NP cells that are genetically manipulated to express hTGF-β1 have a promising effect on the restoration of the intervertebral disc defects. The NP cells transfected with Ad/hTGF-β1 cultured in the 3-D alginate bead systems can show a nearly native phenotype.
OBJECTIVE: To study the effect of overexpression of truncated type II TGF-beta receptor on transforming growth factor-beta 1(TGF-beta 1) autoproduction in normal dermal fibroblasts. METHODS: In vitro cultured dermal fibroblasts were treated with recombinant human TGF-beta 1(rhTGF-beta 1) (5 ng/ml) or recombinant adenovirus containing truncated type II TGF-beta receptor gene (50 pfu/cell). Their effects on regulating gene expression of TGF-beta 1 were observed with Northern blotting. RESULTS: rhTGF-beta 1 up-regulated the gene expression of TGF-beta 1 and type I procollagen. Overexpression of truncated receptor II down-regulated the gene expression of TGF-beta 1. CONCLUSION: Overexpression of the truncated TGF-beta receptor II decreases TGF-beta 1 autoproduction via blocking TGF-beta receptor signal. The results may provided a new strategy for scar gene therapy.
Objective To construct recombinant lentiviral expression vectors of porcine transforming growth factor β1 (TGF-β1) gene and transfect bone marrow mesenchymal stem cells (BMSCs) so as to provide TGF-β1 gene-modified BMSCs for bone and cartilage tissue engineering. Methods The TGF-β1 cDNA was extracted and packed into lentiviral vector, and positive clones were identified by PCR and gene sequencing, then the virus titer was determined. BMSCs were isolated frombone marrow of the 2-month-old Bama miniature pigs (weighing 15 kg), and the 2nd and 3rd generations of BMSCs wereharvested for experiments. BMSCs were then transfected by TGF-β1 recombinant lentiviral vectors (TGF-β1 vector group)respectively at multi pl icity of infection (MOI) of 10, 50, 70, 100, and 150; then the effects of transfection were detected bylaser confocal microscope and Western blot was used to determine the optimal value of MOI. BMSCs transfected by empty vector (empty vector group) and non-transfected BMSCs (non-transfection group) were used as control group. RT-PCR, immunocytochemistry, and ELISA were performed to detect the expressions of TGF-β1 mRNA, TGF-β1 protein, and collagen type II. Results Successful construction of recombinant lentiviral vectors of porcine TGF-β1 gene was identified by PCR and gene sequencing, and BMSCs were successfully transfected by TGF-β1 recombinant lentiviral vectors. Green fluorescence was observed by laser confocal microscope. Western blot showed the optimal value of MOI was 70. The expression of TGF-β1 mRNA was significantly higher in TGF-β1 vector group than in empty vector group and non-transfection group (P lt; 0.05). Immunocytochemistry results revealed positive expression of TGF-β1 protein and collagen type II in BMSCs of TGF-β1 vector group, but negative expression in empty vector group and non-transfection group. At 21 days after transfection, high expression of TGF-β1 protein still could be detected by ELISA in TGF-β1 vector group. Conclusion TGF-β1 gene can be successfully transfected into BMSCs via lentiviral vectors, and long-term stable expression of TGF-β1 protein can be observed, prompting BMSCs differentiation into chondrocytes.
Objective To investigate the effects of caveolin-1 scaffolding domain peptide ( CSD-p)on expressions of extracellular matrix and Smads in human fetal lung fibroblasts. Methods Human fetal lung fibroblasts were cultured in vitro and divided into four groups. A control group: the cells were cultured in DMEMwithout TGF-β1 or CSD-p. A CSD-p treatment group: the cells were cultured in DMEMcontaining 5 μmol /L CSD-p. A TGF-β1 treatment group: the cells were cultured in DMEMcontaining 5 μg/L TGF-β1 .A TGF-β1 + CSD-p treatment group: the cells were cultured in DMEM containing 5 μg/L TGF-β1 and 5 μmol /L CSD-p. Caveolin -1 mRNA was detected by RT-PCR. Caveolin-1, collagen-Ⅰ, α-SMA, p-Smad2,p-Smad3 and Smad7 proteins were measured by Western blot. Results Compared with the control group,the Caveolin -1 mRNA and protein expressions in the cells of TGF-β1 group significantly reduced ( mRNA:0. 404 ±0. 027 vs. 1. 540 ±0. 262; protein: 0. 278 ±0. 054 vs. 1. 279 ±0. 085; P lt; 0. 01) , and the expression levels of collagen-Ⅰ and α-SMA proteins significantly increased ( collagen-Ⅰ: 1. 127 ±0. 078 vs.0. 234 ±0. 048; α-SMA: 1. 028 ±0. 058 vs. 0. 295 ±0. 024) . Meanwhile, the expression levels of p-Smad2 ( 1. 162 ±0. 049 vs. 0. 277 ±0. 014) and p-Smad3 proteins ( 1. 135 ±0. 057 vs. 0. 261 ±0. 046) increased with statistical significance ( P lt; 0. 01) , but the expression level of Smad7 protein significantly reduced( 0. 379 ±0. 004 vs. 1. 249 ±0. 046, P lt;0. 001) . In the CSD-p group, CSD-p had no significant effects on the expressions of above proteins compared with the control group. But in the TGF-β1 +CSD-p group, the overexpressions of collagen-Ⅰ, α-SMA, p-Smad2 and p-Smad3 induced by TGF-β1 were obviously inhibited by CSD-p ( collagen-Ⅰ: 0. 384 ±0. 040 vs. 1. 127 ±0. 078; α-SMA: 0. 471 ±0. 071 vs. 1. 127 ±0. 078;p-Smad2: 0. 618 ±0. 096 vs. 1. 162 ±0. 049; p-Smad3: 0. 461 ±0. 057 vs. 1. 135 ±0. 057; P lt; 0. 01) .Otherwise, the up-regulation of Smad7 ( 0.924 ±0. 065 vs. 0.379 ±0. 004) was found. Conclusions CSD-p can reduce fibroblast collagen-I and α-SMA protein expressions stimulated by TGF-β1 , possibly through regulation of TGF-β1 /Smads signaling pathway. It is suggested that an increase in caveolin -1 function through the use of CSD-p may be an intervention role in pulmonary fibrosis.
Objective To investigate the expression of transforminggrowth factor β1(TGF-β1) and insulin-like growth factorⅠ(IGF-Ⅰ)in new bone after low frequency micromovement. Methods Fifteen female sheep from Shandong province were involved in the study and their bilateral tibias transversely osteotomized in the middle shafts with a defect of 2 mm.The hind limbs were fixed with unilateral external fixators connected to a controlled micromovement device. Ten days after osteotomy, one hind limb of each sheep randomlywas selected to perform micromovement at an amplitude of 0.25 mm and a frequency of 1 Hertz, 30 min a day for 4 weeks ( micromovement group). The other hindlimb served as the control group. Five sheep were sacrificed at 3,4 and 6 weeks after osteotomy, respectively, and specimens were harvested for detecting the expression of TGF-β1 and IGF-Ⅰby immunohistochemistry and RT-PCR. Results Immunohistochemistry: In the third postoperative week in the micromovement group, the expression of TGF-β1 was detected in different areas of new chondrocytes at the margin of callus, mainly in proliferating area, and IGF-Ⅰexpressed in osteoblasts at the margin of endochondral ossification area, calcified and mature chondrocytes and osteocytes. There was seldom expression ofIGF-Ⅰ and little expression of TGF-β1 in the corresponding area in the control one. In the 4th postoperative week in the micromovement group, theexpression of TGF-β1 diminished gradually with the mature of new bone and be located in extracellular matrix and osteoblasts around ossified areas; The expression ofIGF-Ⅰ reached the peak and be located mainly in osteoblasts of new bone surface, maturing osteocytes and calcifing osteoid. But there was little expression of them in the control group. In the sixth postoperative week in the micromovement group, there was a little expression of IGF-Ⅰ expression but little expression of TGF-β1; there was nearly no expression of them in the control group. In the micromovement group, the absorbance values of TGF-β1 at 3 and 4 weeksand of IGF-Ⅰat 3, 4 and 6 weeks were significantlyhigher than those in control group（P＜0.05）. RTPCR: In the third and fourth postoperative weeks in the micromovement group, there was higher expression of mRNA of TGF-β1 and TGF-I than those in control group; in the sixth postoperative week, the expression diminished gradually, but was higher than that in control group. The absorbance values of TGF-β1 at 3 and 4 weeks and IGF-Ⅰat 3, 4 and 6weeks were significantly higher than those of control group（P＜0.05）. Conclusion Low frequency and controlled micromovement in the early stage of the fracture healing can promote the expression of TGF-β1 and IGF-Ⅰ.They worked together to regulate the process of the endochondral ossification, while in the late stage the differentiation of osteocytes and mineralization of osteoid were regulated mainly by IGF-Ⅰ, which played an important role in regulating the cell biological behavior during micromovement.
OBJECTIVE: To investigate the effects of basic fibroblast growth factor (bFGF) on the promoter activities of human alpha 1(I) procollagen gene and the interaction between bFGF and transforming growth factor-beta 1 (TGF-beta 1). METHODS: Fibroblasts of the hypertrophic scar and normal skin from a 3-year-old patient were primarily cultured and subcultured in vitro. Both of the fibroblasts were transient transfected with phCOL 2.5, containing -2.5 kb of 5’f lank sequence of human alpha 1(I) procollagen gene and CAT reporter gene by FuGENE transfection reagent; and treated thereafter by 16 ng/ml bFGF, 2 ng/ml TGF-beta 1 and 16 ng/ml bFGF + 2 ng/ml TGF beta 1 for 24 hours. The relative CAT expression values were determined by CAT-ELISA. RESULTS: TGF-beta 1 bly induced the CAT expression level, however, bFGF not only inhibited the basal CAT expression but also reduced the CAT expression up-regulated by TGF-beta 1 in normal skin and hypertrophic scar fibroblasts (P lt; 0.05). CONCLUSION: bFGF can reduce the promoter activities of human alpha 1(I) procollagen gene and antagonize the role of TGF-beta 1 in up-regulating the promoter activities of human alpha 1(I) procollagen gene in normal skin and hyertrophic scar fibroblasts.
