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 observe the affection of optic nerve under acute ocular hypertension and the effect of protection of bFGF on optic nerve. Methods BSS was perfused into anterior chamber of rabbits to increase the intraocular pressure to cause retinal ischemia. A computer image analysis system was used to count the optic nerve axons.Eyes were intravitreally injected with bFGF and then the number of optic nerve axons of the normal rabbits,and hypertension with and without bFGE treatment groups were counted respectively. Results The number of optic nerve axons in ocular hypertension eyes was less than the normal eyes(P=0.00003).The bFGF treated eyes had more optic nerve axons than the controls(P=0.0078). Conclusions The acute ocular hypertension may cause the loss of the nerve axons,and bFGF may be effective in protecting optic nerve in acute ocular hypertension. (Chin J Ocul Fundus Dis,2000,16:94-96)
To investigate the best way of using fibroblast growth factor (FGF) in wound healing, the following experiments were performed. Twelve Wistar rats were chosen. Four 1.5 cm x 1.5 cm middle-thick skin wounds were made in the back of each rat, 2 in each side, and labelled as number 1 to 4. Number 1 wound of each rat was used as control, only PBS was applied to the wound, 50 microliters per time, twice a day from the first day to 11th day. Number 2 wound was sustained medication group, 50 microliters 4 micrograms/ml FGF was applied twice a day from the first day to 11th day; Number 3 wound was early medication group, 50 microliters 8 micrograms/ml FGF was applied twice a day from the first day to 5th day; Number 4 wound was late medication group, 50 microliters 8 micrograms/ml FGF was added twice a day from the 5th day to 11th day. By day 4, 8, 12 and 16, the area of wounds were measured, and the healing time of each wound was recorded. The elastic fiber, collagen fiber and DNA content were measured by immunohistological method. The result showed that the elastic fiber, collagen fiber and DNA content in the groups of FGF used were more than those in the control group. The healing time of the control group was 14.4 days while that of the early meduation group was 13.4 days, late medation group was 13.5 days and sustained medication group was 12.2 days. It was suggested that FGF could accelerate the wound healing, and sustained use of FGF was the best way of giving the drug.
ObjectiveTo investigate the antibacterial pretreatment protocol for primary fibroblast cell culture from transbronchial biopsies in patients with benign tracheal stenosis (BTS). MethodsFifteen specimens of intratracheal hyperplastic granulation tissue were obtained from 14 BTS patients by transbronchial biopsies. The tissues were divided into 3 groups according to different antibacterial pretreatment with 5 specimens in each group. An usual concentration of antibiotics pretreatment group (group 1) was pretreated by washing with PBS contained 1%-2% penicillin/streptomycin. A high concentration of antibiotics pretreatment group (group 2) was pretreated by washing with PBS contained 6% penicillin/streptomycin. An alchohol and high concentration of antibiotics pretreatment group (group 3) was pretreated by washing with 75% alcohol 3-4 seconds firstly,then by washing with 6% penicillin/streptomycin. After different pretreatment,all tissues were cultured with tissue culture method in the same condition. ResultsThe primary fibroblasts were successfully cultured from the tissue pretreated by method 2 and 3,but not cultured from the tissue pretreated by method 1 with large amount of bacteria. There were significant differences in the furthest radius of cell proliferation between different culture time points in three groups (P<0.01). The differences in the furthest radius of cell proliferation between three groups were not different at 24,48 or 72 h (P>0.05),but were significant between three groups at 96 h (P<0.05). ConclusionAn pretreatment protocol with high concentration of antibiotics or 75% alcohol is feasible in human primary fibroblasts culture from small specimens obtained by transbronchial biopsy.
OBJECTIVE: To analysis the biological characteristics of human fibroblasts transfected by human telomerase reverse transcriptase (hTERT) eucaryotic expression plasmid pGRN145. METHODS: Fibroblasts from children’s foreskin were isolated and cultured in vitro, and the fibroblasts were transfected by pGRN145 with Lipofec-tAMINE PLUS Reagent. After strict screening of hygromycin B, the positive clones were subcultured. The telomerase activity was detected by RT-PCR and TRAP-PCR technique. The cell generation cycle and apoptosis rate were detected by flow cytometry to investigate the proliferative characteristics after transfection, and the chromosome karyotype of transformed cells was analyzed. The collagen secreted by transformed cells was detected by immunohistochemical staining. RESULTS: The morphological properties of fibroblasts did not change obviously after transfection. There were telomerase activity in transfected fibroblasts, while it could not be detected in pre-transfection fibroblasts. The cell generation cycle had no obvious changes between pre-transfection and post-transfection. However, the apoptosis rate of transfected fibroblasts were decreased compared with that of pre-transfection. The fibroblasts transfected by pGRN145 maintained the normal diploid karyotype, as well as the cells could normally secret type I and III collagen. CONCLUSION: The human fibroblasts transfected by pGRN145 has telomerase activity with prolonged life span of culture, which preliminarily proves the availability of establishing standard seeding cell lines of tissue engineering by hTERT plasmid transfection techniques.
ObjectiveTo investigate the effects of liver X receptor agonist, T0901317, on the proliferation, migration and hydroxyproline production of human embryonic lung fibroblasts (HELF). MethodsHELF cells were devided into a control group, a growth factor group, a T0901317 group and three growth factor+T0901317 groups. The cells of the control group were treated with Dulbecco's modified Eagle medium. The cells of T0901317 group were treated with 1.00 μmol/L T0901317. The growth factor+T0901317 groups were incubated with different doses of T0901317 (0.25 μmol/L, 0.50 μmol/L and 1.00 μmol/L) for 2 h. Then the cells of the growth factor+T0901317 groups and the growth factor group were incubated with basic fibroblast growth factor and transforming growth factor-β1 for 24 h. The proliferation, migration and collagen production of HELF were determined by cell counting kit-8 method, transwell chamber, and hydroxyproline method. ResultsCompared with the control group, T0901317 had no effect on the proliferation, migration and hydroxyproline production of HELF. Growth factors could promote the proliferation, migration and hydroxyproline production of HELF significantly. T0901317 could inhibit those effects of growth factors with a dosage-dependent manner. ConclusionT0901317 may inhibit the proliferation, migration and hydroxyproline production of HELF induced by growth factors.
OBJECTIVE: To investigate the changes of fibroblast growth factor (FGF) in burn wounds. METHODS: The FGF expression in the center of wound granulation, the edge of wound, the healed part of wound, the normal skin of patients, and the heal course of second degree burn wounds were detected by immunohistochemical methods. RESULTS: The expression intensity of FGF was different in the different sites of third degree burn wounds. The highest contents of FGF was in the center granulation of burn wounds, the less was in the borderline of wound and healed skin, and the least was in the healed skin. FGF expression mainly concentrated in the middle layer of wound, and almost no FGF expression in normal skin. The most FGF expression was occurred at 14 days after injury in second degree of burn wound. CONCLUSION: The changes of FGF in wounds are closely related to the wound healing, and rational use of FGF can promote wound healing.
OBJECTIVE This paper aims to explore the new method of continuous delivery of epidermal growth factor to wounds by transfected fibroblasts to promote wound repair. METHODS It was constructed a novel chimeric expression plasmid in which the biologically active portion of the human epidermal growth factor (EGF) gene was fused in-frame to the human granulocyte colony-stimulating factor signal sequence. RESULTS Clonally selected human fibroblasts transfected with this construct could secrete biologically active EGF. After the transplantation of irradiated gene-transfected fibroblasts suspended in fibrin glue to murine full-thickness wounds, EGF could be demonstrated for at least seven days in the wounds, slowly decreasing from initially 470 ng/L to 140 ng/L in 7 days. No EGF was found in the wound at 14 days. CONCLUSION A single application of irradiated EGF gene transfected fibroblasts to wounds can continuously deliver the transgene in vivo and can be used to administer drugs to the wound bed during the crucial first seven days of wound-healing.
Abstract To observe the effect of fibroblast growth factor (FGF) on wound healing, 50 mice were divided into 5 groups. On the back of every mouse, 2 wounds were made by operative cuts, one for experiment and the other for control. The wounds of the experimental group were covered with 0.5ml FGF solution (contented FGF 300 μg/ml, heparin 100 μg/ml), whereas the wounds of the control group were covered with 0.5ml 0.9% NaCl solution. All of the wounds were dressed by sterilized gauze, and received the same treatment once a day. After 1,3,5,7,10 days, the mice in every group were sacrificed and the tissues of the wounds were collected and prepared for microscopic examination. The results showed that the capillaries and fibroblasts in the experimental group were markedly increased and reached the peak 2～3 days earlier than those in the control group. It was suggested that FGF promoted the formation of granulation tissue and the wound healing.
OBJECTIVE: To fabricate artificial human skin with the tissue engineering methods. METHODS: The artificial epidermis and dermis were fabricated based on the successful achievements of culturing human keratinocytes(Kc) and fibroblasts (Fb) as well as fabrication of collagen lattice. It included: 1. Culture of epidermal keratinocytes and dermal fibroblasts: Kc isolated from adult foreskin by digestion of trypsin-dispase. Followed by comparison from aspects of proliferation, differentiation of the Kc, overgrowth of Fb and cost-benefits. 2. Fabrication of extracellular matrix sponge: collagen was extracted from skin by limited pepsin digestion, purified with primary and step salt fraction, and identified by SDS-PAGE. The matrix lattice was fabricated by freeze-dryer and cross-linked with glutaraldehyde, in which the collagen appeared white, fibrous, connected and formed pores with average dimension of 180 to 260 microns. 3. Fabrication artificial human skin: The artificial skin was fabricated by plating subcultured Kc and Fb separately into the lattice with certain cell density, cultured for one week or so under culture medium, then changed to air-liquid interface, and cultured for intervals. RESULTS: The artificial skin was composed of dermis and epidermis under light microscope. Epidermis of the skin consisted of Kc at various proliferation and differentiation stages, which proliferated and differentiated into basal cell layer, prickle cell layer, granular layer, and cornified layer. Conifilament not only increased in number, but also gathered into bundles. Keratohyalin granules at different development stages increased and became typical. The kinetic process of biochemistry of the skin was coincide with the changes on morphology. CONCLUSION: Tissue engineered skin equivalent has potential prospects in application of repairing skin defect with advantages of safe, effective and practical alternatives.