OBJECTIVE: To investigate the biological characteristics of human muscle satellite cell cultured in vitro. METHODS: Human muscle satellite cells were obtained from skeletal muscle biopsies of six patients during corrective orthopedic surgery, cultivated in growth medium for ten days, then in differentiation medium for additional five days. Human satellite cells were identified with monoclonal antibody against desmin. Cells were observed under phase contrast microscopy. RESULTS: Human muscle satellite cells proliferated in growth medium, and fused to form myotubes in differentiation medium. After 24 hours in differentiation medium, the confluent satellite cells began to fuse actively and achieved the top level at 72 hours. CONCLUSION: Human muscle satellite cell can proliferate and differentiate in appropriate culture condition. Immunocytochemical detection of desmin is the effective early method to determine satellite cell.
Objective To culture primary parathyroid cells by mean of simulated microgravity, observe their basic morphological characteristics, study survival rate and secretory function of parathyroid cells, and explore more excellent culture mean of parathyroid cells. Methods There were 37 male Wistar rats, the body weight was 150–200 g. The rat was intraperitoneally injected with 1% pentobarbital sodium (50 mg/kg). The parathyroid glands were surgically excised and identified pathologically. The parathyroid gland cells were got and digested them with collagenase Ⅱ, which were divided into three groups: conventional culture group (simple parathyroid cells were cultured), polyglycolic acid (PGA) scaffold culture group (the parathyroid cells were cultured on the PGA scaffold), and simulated microgravity culture group (the parathyroid cells and PGA scaffolds were cultured in simulated microgravity environment). The parathyroid cells were cultured for 1, 3, 5 or 7 days in different culture conditions, then the parathyroid hormone (PTH) was measured, morphological characteristics of the parathyroid cell was observed under phase contrast microscope, survival rate of the parathyroid cells was calculated by acridine orange/propidium iodide staining. Results The parathyroid cell morphologies of most cells were well and center of part of cell mass was necrosis on day 7 in the conventional culture group. The most parathyroid cells were spreading toward the poles along the PGA cell scaffold in the longitudinal direction and the adjacent stents were connected by extracellular matrix on day 7 in the PGA scaffold culture group. The parathyroid cells cultured under the simulated microgravity were got round and formed clusters on day 7 in the simulated microgravity culture group. Compared with the other two groups on day 7, the PTH and the survival rate of the parathyroid cells were significantly higher in the simulated microgravity culture group (P<0.05). Conclusions Parathyroid cells cultured in simulated microgravity environment could maintain better morphology, survival rate is higher, and secretory function is better. Therefore, parathyroid cells cultured in simulated microgravity could be used as good donor cell for treatment of hypoparathyroidism. PGA scaffold could be used as a good carrier for culture of parathyroid cell.
OBJECTIVE: To observe the effects of silks on attachment, shape and function of chondrocytes cultured in vitro. METHODS: The silks from silk worm cocoons were digested by trypsin and coated with polylactic acid to from three dimensional scaffolds for rabbit rib chondrocyte culture. The growth and shape of chondrocytes were observed with phase contrast microscopy, scanning electron microscopy. RESULTS: The chondrocytes were adhered to silks slowly after chondrocytes were seeded into silk scaffolds and cells fixed on silks well 1 or 2 days later. Cells began to proliferate after 3 days and multiplicative growth was observed on the 6th day. Microholes of silk scaffolds were filled with chondrocytes 2 weeks later. Scanning electron microscopy showed that there was a lot of extracellular matrix surrounding cells. CONCLUSION: Silks are ideal for attachment, growth and function maintenance of chondrocytes, and silks can be used as scaffolds for chondrocytes in three dimensional culture.
Objective To investigate the influence of the exogenouscollagen on the function of cells in construction of artificial biotendon.Methods Three materials including human hair, carbon fiber(CF) and polyglycolic acid (PGA) were combined with exogenous collagen and co-cultured with standard transferred human embryonic tenocytes at a concentration of 3×106/mm3 in vitro. The cell number and morphology were observed under inverted microscope and scanning electron microscope after 2 hours, 3 days and 5 days.Results In the artificial biotendon combined with collagen, the cells concentrated around the materials and the cells adhering to the materials turned into round after 2 hours. After 3 days, the adhering cells increased. After 5 days, the shape of the cells changed from round to spindle.ConclusionExogenous collagen will facilitate the cells to adhere onto materials and proliferate.
Objective To investigate the effect of dexamethasone, recombinant human fibroblast growth factor (rhFGF) and recombinant human bone morphogenetic protein 2 (rhBMP-2) on the proliferation and differentiation of marrow stromal stem cells (MSCs) for their further application in tissue engineering. Methods MSCs were isolated and cultured in vitro, and then exposed to different dose of dexamethasone (10-8 mol/L,10-7 mol/L,10 -6 mol/L), rhFGF (50 ng/ml,200 ng/ml,500 ng/ml) and rhBMP-2 (50 ng/ml,500 ng/ml,1 000 ng/ml) respectively. The total protein and alkaline phosphatase (ALP) activity of each group was measured on 4th and 7th day. Results Exposure of MSCs with 10-6mol/L dexamethasone inhibited protein synthesis without obvious effects on ALP expression. The application of rhFGF significantly promoted cell proliferation but inhibited ALP activity. In comparison, ALP expression was significantly enhanced by treatment of rhBMP-2 at concentration of 500 ng/ml，1 000 ng/ml. Conclusion The exposure of dexamethasone as well as rhBMP-2 to MSCs with an appropriate concentration promotes osteogenic expression without reverse effects on cell proliferation, which indicates the great potential value in cell-based strategy of bone tissue engineering.
PURPOSE:In search of the mechanism for photic retinal injury. METHODS:A visible light damage model was established in the primary cultured healthy,adult human RPE cells by using intense fluorescence light (2 400 Lx). RESULTS:Electron microscopy revealed swelling of the mitochondria and obscurity of nuclear membranous structure in the light damaged cells. The decrease or dissolution of organelle,vacuolization of cytoplasm and myelinic degeneration were found in some severely damaged cells. The level of intracellular SOD was decreased to 41% of that of the controls (P＜0.05). CONCLUSION:The structure of the RPE was damaged by the light radiation and the level of intracellular SOD was decreased. These suggested the light damage might be associated with the production of free radicals and the lipid perioxide reaction in membranous structure of cell. （Chin J Ocul Fundus Dis,1996,12: 174-175 ）
Objective To investigate the changes of cellular configuration and polarized characteristic of visual pigment during the development of rod cells of neonatal calf in vitro. Methods Retinal cells of neonatal calf were dissociated and cultivated for 10, 20, 30 and 40 days in vitro were used for immunocytochemical analysis. Retinal rod cells were identified by rho4D2 antibody. The configuration of positive cells and rhodopsin molecular distribution were analysed at different cultivated time. The immuno-reactivity of positive cells was measured by image analysis system. Results The rho4D2 immuno-reactive cells included small round cells without protuberance and the cells with protuberance at the peak. At the 10th day after cultivation, the visual pigment immunoreaction was suffusive in the whole cell membrane and apical process; while at the 30th and 40th day, it gathered at the membrane of apical process or one pole of the cells. The results of quantitative analysis showed that the immunoreactive intensity of positive cells at the 20th day after cultivation was ber than that at the 10th day; while there was no significant difference among the immunoreactive intensity at the 20th, 30th, and 40th day. Conclusions Rod cells at the 30th and 40th day after cultivation have the polarized characterization and visual pigment molecular distribution with high level of expressive ability of protein, which are mature neurons. (Chin J Ocul Fundus Dis, 2005, 21: 394-396)
Objective To locate sinoatrial node (SAN) in suckl ing pigs, to develop a rel iable method for isolation, purification and cultivation of SAN cells and to observe the compatibil ity of SAN cells and Col I fiber scaffold. Methods Five newborn purebred ChangBaiShan suckl ing pigs (male and female), aged less than 1-day-old and weighing 0.45-0.55 kg, wereused. Multi-channels electrophysiological recorder was appl ied to detect the original site of atrial waves. Primary SAN cells harvested from that area were cultured by the conventional culture method and the purification culture method including differential velocity adherent technique and 5-BrdU treatment, respectively. Atrial myocytes isolated from the left atrium underwent purified culture. Cell morphology, time of cell attachment, time of unicellular pulsation, and pulsation frequency were observed using inverted microscope. The purified cultured SAN cells (5 × 105 cells/mL) were co-cultured with prewetted Col I fiber scaffold for 5 days, and then the cells were observed by HE staining and scanning electron microscope (SEM). Results The atrial waves occurred firstly at the area of SAN. The purified cultured SAN cells were spindle, triangular, and irregular in morphology, and the spindle cells comprised the greatest proportion. Atrial myocytes were not spindle-shaped, but primarily triangular and irregular. The proportion of spindle cells in the conventional cultured SAN cells was decreased from 73.0% ± 2.9% in the purified cultured SAN cells, to 44.7% ± 2.3% (P lt; 0.01), and the proportion of irregular cells increased from 7.0% ± 1.7% in the purified cultrued SAN cells to 36.1% ± 2.6% (P lt; 0.01) . The proportion of the triangular cells in the purified and the conventional cultured SAN cells was 20.0% ± 2.1% and 19.2% ± 2.5%, respectively (P gt; 0.05). At 5 days after co-culture, HE staining displayed lots of SAN cells in Col I fiber scaffold, and SEM demonstrated conglobate adherence of the cells to the surface and lateral pore wall of scaffold, mutual connections of the cell processes, or attachment of cells to lateral pore wall of scaffold through pseudopodia. Conclusion With accurate SAN location, the purification culture method containing differential velocity adherent technique and 5-BrdU treatment can increase the proportion of spindle cells and is a rel iable method for the purification and cultivation of SAN cells. The SAN cells and Col I fiber scaffold have a good cellular compatibil ity.
Abstract An experiment was carried out to investigate the possibility of the establishment of an osteoblasts bank which could supply osteoblasts in repairing bone defect. Osteoblasts were isolated from thetibial periosteum of eight New-Zealand rabbits and cultured in votro. A bone defect, 1.5cm in length was made in both radii of each of the 8 rabbits. The cultivated osteoblasts, gelfoam as a carrier were randomly implanted into the defects of the radii of rabbits. Accordingly, the contralateral radial defects wereimplanted with gelfoam absorbed with the Hanks solution as control. The healing of bone defects was evaluated by roentgenographic examination at 2, 4, 8 and 12 weeks after operation, respectively. It was shown that the implanted cells had osteogenetic capability and could be possible to promote healing of the bone defects. It was suggested that further study needed to be carried out in this field.