Objective To investigate the possible mechanism of the fibroblasts inducing the vascularization of dermal substitute. Methods Fibroblasts were seeded on the surface of acellular dermal matrix and cultivated in vitro to construct the living dermal substitute. The release of interleukin 8 (IL 8) and transfonming growth factor β 1(TGF β 1) in culture supernatants were assayed by enzyme linked immunosorbent assay, the mRNA expression of acid fibroblast growth factor (aFGF) and basic fibroblast growth factor (bFGF) were detected by RT-PCR. Then, the living substtute was sutured to fullth ickness excised wound on BALBouml;C m ice, and the fate of fibroblast w as observed by using in situ hybridizat ion. Results Fibroblasts cultured on acellular dermalmat rix p ro liferated and reached a single2layer confluence. Fibroblasts could secret IL 28 (192. 3±15. 9) pgouml;m l and TGF-B1 (1. 105±0. 051) pgouml;m l. There w as the mRNA exparession of aFGF and bFGF. Fibroblasts still survived and proliferated 3 weeks after graft ing. Conclusion Pept ides secreted by fibroblasts and its survival after graft ing may be relat ive to the vascularizat ion of the dermal subst itute.
OBJECTIVE To review the recent advances in fibroblast study and its role in wound repair. METHODS Recent original articles related to wound repair were retrieved extensively, and the effect of fibroblast on every stages of repair were summed up and comprehended. RESULTS Fibroblast plays important roles in granulation formation, wound contraction, matrix synthesis, wound repair, scar formation and scarless repair by means of growth factors modulation. CONCLUSION The understanding of fibroblast in the wound repair can promote the progress of biological therapy of wound repair and scar prevention.
Objective To explore the osteogenic potential of cervical intervertebral disc fibroblasts in vitro, to investigate the regulatory factors of recombinant human bone morphogenetic protein 2(rhBMP-2) and tumor necrosis factor α(TNF-α) on osteogenic phenotype of fibroblasts and to discuss the condition that facilitates osteogenesis of fibroblasts. Methods Theannulus fibroblasts cell lines of experiment goats were established in vitro and the biologicspecificity was found. According to different medias, 4 groups were included in this experiment: control group, TNF-α group ( 50 U/ml TNF-α), rhBMP-2 group (0.1 μg/ml rhBMP-2) and TNF-α+rhBMP-2 group (50 U/ml TNF-α+0.1 μg/ml rhBMP-2). Thefibroblasts were incubated in the media for about 3 weeks,and then the markers for osteogenic features were investigated by biochemistry, histochemistry observations. Results rhBMP-2 and TNF-α had no effect on the proliferation of fibroblasts from the experiment goats. rhBMP-2 or TNF-α could stimulate fibroblasts to secrete alkaline phosphatase and collagen type Ⅰ. The combined use of rhBMP-2 and TNF-α or the single use of rhBMP-2 could make fibroblasts to secrete osteocalin and the morphological changes of the fibroblasts were very obvious. Histochemical study of the nodules with specific new bone labeler(Alizarin red S) revealed positive reaction, denoting that the nodules produced by the fibroblasts werebone tissues. There was statistically significant difference(Plt;0.05) inALP activity between 3 experimental groups and control group and in secretion of osteocalcin between rhBMP-2 group, TNF-α+rhBMP-2 group and control group. Conclusion The results point out clearly that rhBMP-2 can induce theosteogenic potential of annulus fibroblasts in vitro.
OBJECTIVE: To build the trestle of tissue engineering for skin with the collagen. METHODS: The collagen was obtained from the baby cattle hide pretreated by Na2S and elastinase and Protease M, then the collagen was dissolved in 0.5 mol/L acetic acid solution. The collagen was treated with Protease N to minimize its immunogenicity. The resulting collagen could be used to build the trestle of tissue engineering for skin because of good biocompatibility. The collagen molecular weight and structure were analyzed by SDS-PAGE. The bioactivity of trestle was tested in the experiment of the mice wound healing and the cell implantation. RESULTS: The SDS-PAGE result of the collagen treated by Protease M showed the typical spectrum of type I collagen. The built trestle was a collagen sponge matrix in which micropore size was 50-200 microns. It could accelerate wound healing and the implanted fibroblasts could proliferate well. CONCLUSION: The collagen treated by Protease N can get good biocompatibilily and is suitable for building the trestles of tissue engineering for skin with good bioactivity.
Objective To observe the proapoptotic effect ofthe homogenate of different parts of pig’s full thickness dermal wounds on cultured fibroblasts. Methods The tissues were dissected from the wound center and subneoepithelium separately 15 days after homogenization and sterilization, the specimens stored at -70℃. The forth passage of the fibroblasts were cultured for 16 hours in different culture solutions and were grouped into 7 groups: DMEM containing 5% fetal bovine serum as Group Ⅰ, DMEM containing 5% homogenate of tissue from wound center as GroupⅡ, DMEM containing 5% homogenate of tissue from subneoepithelium as Group Ⅲ, the culture solution of Group Ⅱmixed with 10 μg/ml GM6001 in Group Ⅳ, with the culturing medium of Group Ⅲplus 10 μg/ml GM6001 as Group Ⅴ, the culture solution of Group Ⅱ mixed with 10 ng/ml aFGF as Group Ⅵ, and the culture solution of Group Ⅲ mixed with 10 ng/ml aFGF as Group Ⅶ. In all groups except Group Ⅰ, the fibroblasts of the 6 pigs were treated with the homogenate derived from the same animal respectively. After being incubated in Annexin Ⅴ-FITC and PI, cells were analyzed by Flow Cytometry and the rate of apoptotic cells was acquired. The data were analyzed by SPSS 11.0 using Leastsignificant Difference test(LSD). Results The apoptotic rate of the 7 groups were as follows:4.39%±0.41% in Group Ⅰ，10.98%±1.42% in Group Ⅱ，13.47%±1.44% in Group Ⅲ，7.2%±0.46% in Group Ⅳ，12.1%±0.85% in Group Ⅴ，3.9%±0.63% in Group Ⅵ，9.8%±0.50% in Group Ⅶ； there were significant differences between every two groups except Group Ⅰand Group Ⅵ. Conclusion Homogenate of the tissue derived from the subneoepithelium has greater proapoptotic effect than that from the wound center; the proapoptotic effect of homogenate of the tissue both under neoepithelium and in wound center can be significantly alleviated by acid fibroblast growth factor, partly because of MMPs.
Objective To establish a method of constructing skin-equivalents (SE) by the hair follicle stem cells (HFSC) and the fibroblasts. Methods The K19 immunostainning was employed to localize the HFSC in the human scalp from the cosmetic surgery. The isolated HFSC through the enzyme digestion were seeded on the dermal equivalent (DE) formed by polymerization of the fibroblasts and collagen. After being cultured between the air-liquid interface for 14 days, SE were harvested and used for an evaluation. Results HFSC were located mainly in the outer root sheath in the hair follicle. Based on DE, the growing HFSC could build a fullydeveloped and multilayered epidermis with the basal membrane formedb etween the epidermis and the dermis. The fibroblasts were active and spread evenly in the collagen matrix. Conclusion The hair follicle stem cells located in the outer root sheath can be successfully used to construct skin-equivalents in vitro and have a promising clinical use in the treatment.
ObjectiveTo investigate the effect of basic fibroblast growth factor (bFGF) on expression of apoptosisrelated genes in retinal ischemiareperfusion injury (RIRI).MethodsTwentyeight rats were divided into normal, ischemia and treatment group randomly; and the latter two groups were subdivided into 6 subgroups according to different time points: 1 hour, 6, 12, 24, 48, and 72 hours after reperfusion. The rats′ model of experimental RIRI was established. After intravitreously injected with bFGF (treatment group) or balanced saline solution (ischemia group), the expressions of wide type p53 (WTp53)，c-fos, and c-jun in each subgroups were detected by streptavidinbiotin complex of immunohistochemistry.ResultIn ischemia group, the expression of WTp53,c-fos and c-jun was found 6 hours after reperfusion, reached the peak at the 24th hour after reperfusion, kept expressing bly at the 48th hour, and decreased obviously at the 72nd hour. In treatment group, the rule of changes of expression of WTp53, c-fos and c-jun was similar to which in ischemia group, except that the expression amount was obvious decreased. There was statistical significance of the expression of WTp53, c-fos and c-jun between the ischemia and treatment group 6-48 hours after reperfusion (P＜0.05）. ConclusionThe expression of WTp53,c-fos,and c-jun in retinal ganglion cell layer and inner nuclear layer may increase led by RIRI；WTp53,c-fos,and c-jun may be involved in the generant mechanisms of RIRI by playing parts in apoptosis；bFGF can inhibit the increase of expression of WTp53,c-fos,and c-jun in RIRI.Thus, which may has therapeutic effect on RIRI.( Chin J Ocul Fundus Dis,2005,21:310-313)
Objective To investigate the phenotypic change and proliferation of fibroblasts in human inflammatory strictured bile duct wall. Methods We observed the density and ultrastructure of fibroblasts, and the histologic structure in human normal bile duct wall and inflammatory strictured bile duct wall by light and electron microscope.Results The results showed that fibroblasts were the main source of extracellular matrix production in bile duct wall. The phenotype of fibroblasts in inflammatory strictured bile duct wall changed obviously, quiescent fibroblasts were activated and transformed to myofibroblasts, with massive proliferation. Conclusion These data suggest that massive proliferation of activated fibroblasts and myofibroblasts is the main source of extracellular matrix overproduction which results in inflammatory bile duct stricture.
Objective To investigate a change in the differentiation and biological function of the cultured rat fibroblast (FB) transfected by the myoblast determining gene (MyoD) and the connexin 43 (Cx43) gene and to explore the possible mechanism of the MyoD and Cx43 genes on treatment of ischemic heart disease (IHD). Methods The gene cloning technology was used to construct the eukaryotic expressed plasmid vector pLenti6/V5-DEST-MyoD and pLenti6/V5DEST-Cx43 in which MyoD cDNA or Cx43 cDNA was inserted. The RFL-6 FB cells were transfected with exogenetic MyoD cDNA or Cx43 cDNA via lipofectamine, followed by the Blasticidin (50 μg/ml) selection, according to the lentiviral expression system (ViraPower) protocol. The expression and the biological functions of MyoD and Cx43 in the transfectants were testified by RT-PCR, Western blot, and molecular and immunocytochemical methods. The mophological structure changes of the cells were observed under microscope before and after the transfection. Results The expression of MyoD and Cx43 was detected in the MyoD and Cx43 genes transfected FB with RT-PCR and Western blot. The immunocytochemical methods indicated the expressionsof the MyoD and Cx43 genes, while desmin and αactin were found in these cells. The myotubes were found from the cultures incubated a week in the differentiation medium, in which the transfected cells had a characteristic of the filamentsin their cytoplasm and showed a myoblast morphology. Conclusion MyoD cDNA can induce the cultured FB to differentiate into the myoblasts and Cx43 cDNA can enhance the gap junctional intercellular communication between the cell and the cell. Thus, a further experimental foundation for the therapy of IHD can be provided.
ObjectiveTo explore the reaction of normal skin fibroblasts from different sites of human body to cyclic stretch.
MethodsThe normal skin tissues from scapular upper back and medial side of upper arm of 3 patients were cultured in vitro. Fibroblasts of experimental group were loaded by cyclic stretch with 10% amplitude for 24, 36, and 48 hours respectively. Fibroblasts of control group were cultured without cyclic stretch. The morphologic changes were observed using inverted microscope. CCK-8 method was used to detect the proliferation of the fibroblasts. The expressions of integrin β1 mRNA, p130Crk-associated substance (P130Cas) mRNA, transform growth factor β1 (TGF-β1) mRNA, and collagen type Ⅰ α1 chain (COL1A1) mRNA were detected by real-time quantitative PCR. The protein levels of collagen type Ⅰ and TGF-β1 were detected by ELISA.
ResultsThe cultured cells showed a significantly increased cell proliferation ability, and apparent orientation after the applied strain. The proliferation activity, mRNA expression levels of integrin β1, P130Cas, and TGF-β1, protein levels of TGF-β1 in back skin were significantly higher than those in arm skin (P<0.05) when the fibroblasts were loaded for 36 and 48 hours, but no significant difference between back skin and arm skin at 24 hours (P>0.05). There was no significant difference in mRNA expression level of COL1A1 and protein level of collagen type Ⅰ between back skin and arm skin at 24, 36, and 48 hours (P>0.05). There was no significant difference in all above indexes between back skin and arm skin in control group (P>0.05).
ConclusionFibroblasts from scapular upper back and medial side of upper arm display different reactions to cyclic stretch, which indicates that there exists site difference in the reactions of fibroblasts to cyclic stretch. It might be related with the incidence of hypertrophic scar in different sites of the body.
