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 construct human brain-derived neurotrophic factor retroviral vector-pLXSN (hBDNFpLXSN), and to evaluate the bioactivity of hBDNF. Methods The genome mRNA was extracted from embryonic brain tissue of a 5-month-old infant, the hBDNF gene sequence was obtained with RT-PCR technology, and hBDNF-pLXSN constructed in vitro was used to infect the fibroblasts (NIH/3T3). The expression of hBDNF was identfied by the immunohistochemistry method, and the NIH/3T3 and BDNF biological activities were determined by culture of the PC12 cells and dorsal root gangl ia. Results The hBDNF-pLXSN was constructed successfully by sequencing analyses. The infected NIH/3T3 showed positive expression of hBDNF. The infected NIH/3T3 could product hBDNF. Bioactivity of the products could support the PC12cell survival and neurite growth in the primary cultures of dorsal root gangl ia neurons of mice. Conclusion hBDNF-pLXSNvirus has the abil ity to infect NIH/3T3 and make it expressed and secreted hBDNF with the biological activity. It can be used to treat facial paralysis as a gene therapy.
Objective To investigate an effect of compressive stress on proliferation and apoptosis of human hyperplastic scar fibroblasts（HSFb） in vitro. Methods HSFb were obtained from a 20 year old female patient who developed a hyperplastic scar 3 months after operation for a largearea burn. HSFb were isolated, and were cultured in vitro with the simplified airpressure controlled cellculture instrument, and then they were randomly divided into the following 8 groups: the control group (no stress) and the 7 continuous compressive stress groups, which respectively underwent the 5, 10, 15, 25, 50, 100 and 150mmHg(1mmHg=0.133 kPa) pressure treatment for 4d ays. The absorbance (A) of the cell and the inhibition ratio (IR) of the cell proliferation were determined by the MTT assay, the cell growth cycle was determined by the flow cytometer, and the cell apoptosis was observed by the AnnexinV binding with PI labeling method. Results In the 5, 10, 15, 25, 50, 100 and 150mmHg pressure groups and the control group, the A values of the cells were 0.228±0.004, 0.226±0.003, 0.213±0.005, 0.180±0.005, 0.172±0.007, 0.165±0.004, 0.164±0.004 and 0.230±0.005, respectively; the IRs of the cell proliferation were 0.8%，2.0%，7.3%，21.7%，252%， 28.2% and 0, respectively;the ratios of the cells in G1 were 71.80％±0.44％, 72.32％±0.40％, 74.56％±1.01％, 82.82％±2.76％, 86.77％±2.06％, 88.23％±1.27％, 89.11％±1.74％ and 71.6％±0.49％,respectively; the cell apoptosis ratios were 4.22％±0.49％, 5.12％±0.74％ , 8.58％±0.79%, 19.28％±1.40%, 25.60％±1.21%, 3580％±2.39%, 36.18％±2.38% and 4.00％±0.36％, respectively. In the 5 and 10mmHggroups there were no statistically significant differences in all the above parameters when compared with those in the control group (P＞0.05); however, in the 15, 25,50, 100 and 150mmHg groups there were statistically significant differences in the above parameters when compared with those in the control group (P＜0.05). Furthermore, in the 10, 15, 25 and 50 mmHg groups, there were statistically significant differences in the Avalue of the cells and the ratios of the cells in G 1 when compared with each other (P＜0.01). By contrast, there were no statistically significant differences in the 50, 100 and 150 mmHg groups when compared witheach other (P＞0.05). In the 10, 15, 25, 50 and 100mmHg groups there werestatistically significant differences in the cell apoptosis ratio when comparedwith each other (P＜0.01). In the 100 and 150 mmHg groups there were no such statistically significant differences when compared with each other (P＞0.05).Conclusion A continuous compressive stress when given properly can have a combined effect of the proliferation inhibition and the apoptosis promotion on HSFb in vitro, and this kind of combined effects can becomeone of the important mechanisms for the pressure therapy in treating hyperplastic scar.
Objective To evaluated the role of wt-P53 protein in telomerase regulation in keloid fibroblasts(KFBs). Methods The fibroblasts were derived from humankeloid tissue which was proved by pathological diagnosis. KFBs were divided into 2 groups, the transfection group and the untransfection group. wt-p53 gene was transfected into the fibroblasts by adenovirus vectors in the transfection group. The KFBs untransfected with wt-p53 gene served as control (untransfection group). After 48 hours of transfection, the expression of wt-P53 protein was analyzed by both Western blotting and immunofluorescence method, respectively. The telomerase activity was evaluated by TRAP-ELISA after 1-7 days of transfection. Results All the KFBs from 2 groups expressed wt-P53 protein. But the expression level of wt-P53 protein in the transfection group was significantly higher than that in the untransfection group.At the same time of high expression of wt-P53 protein, the telomeraseactivity of KFBs in transfection group was significantly lower than that in theuntransfection group(P＜0.05). Conclusion High level expression of wt-P53 protein can transiently inhibit the telomerase activity of KFBs.
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.
Objective To observe the effects of keratinocytes on proliferation and collagen secretion of fibroblasts. Methods The conditioned medium,collected from cultured keratinocytes, was added to the cultured fibroblasts as the tested groups(12.5％, 25% and 50％ groups) and DMEM as control group. The MTT, hydroxyproline coloricmetric method and flow cytometer were employed to measure the fibroblast proliferation, the collagen secretion andthe change of the cell cycle.Results In fibroblast proliferation, the absorbency(A) value of tested groups was significantly different from that of the control group (P＜0.01). A value increased as increasing concentration, there was statistically significant difference betweetheconcentrations of 25%,50% and the concentration of 12.5%(P＜0.01), but no statistically significant difference between the concentrations of 25% and 50%(P＞0.01). In collagen secretion, there was no statistically significant difference between the tested groups and the control group(P＞0.01), and between the tested groups(P＞0.01). In cell cycle, 50% of conditioned medium could make the fibroblast pass the limit of G1/S and S/G2 period, the cell rates of S,G2-M period increased. Conclusion The conditioned medium from keratinocytes can increase fibroblasts proliferation, have little effect on general collagen secretion.
Objective To investigate the influence of lipopolysaccharide(LPS) on the proliferation and collagen synthesis of normal human skin fibroblasts so as to elucidate its relation with skin wound healing. Methods Fibroblasts wereisolated and cultured in vitro, and then exposed to different doses of LPS(0.005, 0.010, 0.050, 0.100, 0.500, and 1.000 μg/ml) from E.coli055∶B5 respectively. Then the absorbance (A) value of fibroblasts was determined with the colorirneteric thiazolylblue (MTT) assay, and the cell number was counted under inverted phase contrast microscope from the 1st day to the 9th day after LPS administration, and collagen synthesis of fibroblasts in culture medium was measured with the method of pepsin digestion after incorporation of 3Hproline into stable, single-layered, confluent fibroblasts at 7 days after LPS administration. Results Compared with control group, A value increased with the increasing concentration of LPS (0.005 μg/ml 0.500 μg/ml) and LPS of 0.100 μg/mlgroup had the best effect. The difference was remarkable from the 5th day to the 9th day(P＜0.05). A value decreased when challenged with the LPS of 1.000 μg/ml and the difference was remarkable from the 3rd day to the 9th day(P＜0.05). Cell number increased with theadministration of LPS of different concentrations (0.005 μg/ml 0.500 μg/ml) and LPS of 0.100 μg/mlgroup had the best effect. The difference was remarkable from the 1st day to the 6th day(P＜0.05). Cell number decreased remarkably when challenged with LPS of 1.000 μg/ml and the difference was remarkable from the 2nd day to the 9th day(P＜0.05). Collagen synthesis increased when challenged with LPS of different concentrations (0.005 μg/ml 0.500 μg/ml) and the 0.100 μg/ml group had the best effect. However, when the dose of LPS reached 1.000 μg/ml, it inhibited collagensynthesis. Conclusion LPS could promote the proliferation andcollagen synthesis of fibroblasts within a certain range of low doses, but over-high dose ofLPS might inhibit the proliferation and collagen synthesis of fibroblasts, suggesting that LPS of certain concentrations might contribute to wound healing, while excessive LPS has negative effect on wound healing.
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 evaluate the effects of cryopreserved cultured allogenic dermal fibroblasts on angiogenesis and fibroplasia while artificial dermis grafting by spraying the cells on the graft bed.Methods Full thickness skin defect was made on the back of Wistar rat, fibroblasts mixed into fibrin glue (fibroblast group) and same amount fibrin glue (control group) were sprayed separately between the wound bed and artificial dermis in cell density of 1.0×105 cells/cm2 before the artificial dermis was grafted. On day 5 after grafting, the graft and surrounding tissue were examined histologically for angiogenesis and fibroplasia in the dermis and wound bed with hematoxylin eosin stain, VEGF antibody stain, Masson’s trichrome stain and India ink stain. Evans blue perfusion methodwas also used for detecting the angiogenesis quantitatively.Results In the fibroblast group, the angiogenesis of graft bed was significantly accelerated onday 5 after grafting; the numbers of the newly formed capillaries were 9.64±2.36/HP in the fibroblast group and 3.88±1.62/HP in the control group (P＜0.05). And on day 10 after grafting the angiogenesis was accelerated not only in graft bed but also in the artificial dermis when compared with control group, the newly formed capillaries network was clearly observed in the artificial dermis. Otherwise, the synthesis of collagen was increased in the dermis on day 10 after grafting in the fibroblast group when compared with control group. The immunoreactivity of VEGF antibody in the fibroblast group also showed a ber expression than that in control group on day 5 after grafting, the numbers of positive cells were 46.04±8.90/HP in the fibroblast group and 30.08±7.76/HP in the control group(P＜0.05).Conclusion Transplantation of cryopreserved dermal fibroblasts while artificial dermis grafting can accelerate the angiogenesis and fibroplasia in the artificial dermis and graft bed, thereby accelerate the formation of dermallike tissue in the artificial dermis.
Objective To compare the efficiency of epidermis cell culture between big graft method and small strip method. Methods The big graft method was to cut the skin tissue reticularly from dermis layer while the epidermis were not cut off. After it was digested fully in trypsin, theepidermis was separated from skin and was used to culture epidermal cells. The small strip method was routine. The time to cut the skin and to separate the epidermis was recorded, and the number and quality of cells were compared between two methods. Results It took 8-10 minutes to cut an area of 5 cm2 skin into small strips and 1-2 minutes into big grafts. It took 10-15 minutes to separate the epidermis from the same area skin by small strip method and 2 minutes by big graft method. The cells showed better vigor and its number was more by big grafts than by small strips.The chance of fibroblast contamination was reduced obviously. Conclusion The big graft method is simpler than the small strip method and can culture more epidermis cells with less chance of fibroblast contamination.