RESUMO
Poly-N-isopropylacrylamide (PNIPAAm) is a new kind of intelligent material. It shows favorable thermo sensitivity because of the structure of hydrophilic acrylamino and hydrophobic isopropyl. PNIPAAm also shows good biocompatibility and non-toxicity. All the characters as above make it an ideal extra cellular matrix material for tissue engineering. This paper reviews its application in tissue engineering.
Assuntos
Animais , Humanos , Acrilamidas , Química , Resinas Acrílicas , Materiais Biocompatíveis , Temperatura Alta , Polímeros , Química , Engenharia Tecidual , Alicerces TeciduaisRESUMO
This study was aimed to examine the expression of apoptosis-associated gene Fas in HeLa cell, explore the effects of the co-immobilized cytokines (tumor necrosis factor-alpha and interferon-gamma), and probe the potential mechanism of action. The preparation and application of the research couple IFN-gamma and TNF-alpha to the polystyrene cell culture plate were performed using the Photo-immobilization method, with different doses (20 ng/well and 200 ng/well) and synthesized optical active material. HeLa cells were treated with cytokines for two dose and 1, 3, 6 days. The result showed that the free cytokines induced HeLa apoptosis quickly, yet the HeLa apoptosis induced by co-immobilized cytokines had longer effect.
Assuntos
Humanos , Apoptose , Genética , Sinergismo Farmacológico , Células HeLa , Proteínas Imobilizadas , Química , Farmacologia , Interferon gama , Química , Farmacologia , Fator de Necrose Tumoral alfa , Química , Farmacologia , Regulação para Cima , Receptor fas , MetabolismoRESUMO
This study inquired into the mechanisms of co-immobilized cytokines and free cytokines-induced apoptosis on HeLa cells. With the use of photochemical fixed method, TNF-alpha/IFN-gamma were co-immobilized on a 24-well polystyrene culture plate. HeLa cells were stained with fluorescent probe JC-1 to detect the changes of mitochondrial membrane potential (deltapsim), and then were examined by flow cytometry. The results showed that co-immobilized cytokines could induce the apoptosis of HeLa cells in a dose-independent manner. When treated with low-dose of co-immobilized cytokines (20ng/ml), the mitochondrial membrane potential (deltapsim) of HeLa cells continually decreased in 6 days. These indicate that low dose co-immobilized cytokines have a long-term of apoptosis-inducing effect on HeLa cells. We assume that there is close relationship between the mitochondrial membrane potential decrease and the apoptosis of HeLa cells.
Assuntos
Humanos , Apoptose , Relação Dose-Resposta a Droga , Células HeLa , Proteínas Imobilizadas , Farmacologia , Interferon gama , Farmacologia , Potencial da Membrana Mitocondrial , Membranas Mitocondriais , Fisiologia , Fator de Necrose Tumoral alfa , FarmacologiaRESUMO
The aim of this study was to evaluate the changes in the expression of Bax, Bcl-2 and P53 when HeLa cells were induced by free cytokines or co-immobilized cytokines. The cells were induced for 24 hrs,72 hrs, 120 hrs and 168 hrs. Then, the expression of Bax, Bcl-2 and P53 was observed by immunohistochemistry. The average optic density of reaction products was tested by image analysis. Lastly, data were analyzed statistically. After the HeLa cells were induced for 120 hrs, the average optic denisity of Bcl-2 was much decreased. However, the average optic Bax was much increased. The average optic density of P53 also increased with the increase of time. The results suggest that HeLa apoptosis was induced by tumor necrosis factor-a and interferon -gamma, and the increasing expression of P53 may induce the expression of Bax and prevent the expression of Bcl-2, via the mitochondrial induction of cell apoptosis.
Assuntos
Humanos , Apoptose , Células HeLa , Proteínas Imobilizadas , Farmacologia , Interferon gama , Farmacologia , Fotoquímica , Métodos , Proteínas Proto-Oncogênicas c-bcl-2 , Metabolismo , Fator de Necrose Tumoral alfa , Farmacologia , Proteína Supressora de Tumor p53 , Metabolismo , Proteína X Associada a bcl-2 , Genética , MetabolismoRESUMO
IFN-gamma and TNF-alpha were co-coupled to the polystyrene cell culture plate by the photo-immobilization method. To investigate the synergistic effect of IFN-gamma and TNF-alpha on the HeLa cells, HeLa cells were treated with co-coupled cytokine or non-coupled cytokine in a time course in this study. The morphology detection, cell cycle analysis by flow cytometry, phosphatidyl serine analysis and capase-3 activity detection demonstrated that the two kinds of treatments both induce HeLa cells apoptosis. Non-coupled cytokine worked more quickly while co-coupled cytokine kept more permanent effect. The caspase-3 activity assay indicated that the caspase-3 activity of HeLa cells treated with non-coupled cytokine is higher than that of HeLa cells treated with co-coupled cytokine. This may imply that co-coupled cytokine not only induces the caspase-dependent pathway, but also induces the caspase-independent pathway.
Assuntos
Humanos , Apoptose , Caspase 3 , Metabolismo , Sinergismo Farmacológico , Células HeLa , Proteínas Imobilizadas , Farmacologia , Interferon gama , Farmacologia , Fator de Necrose Tumoral alfa , FarmacologiaRESUMO
The bioactive protein-phycocyanin and all the proteins of Spirulina Platensis were isolated and purified. Photo-reactive proteins were synthesized by coupling the proteins with (N-(4-azidobenzoyloxy)succinimide) and were spread onto the 24-well cell culture polystyrene plate. Then the coated surface was exposed to ultraviolet irradiation for chemical fixation of proteins via the conversion of the phenylazido group to the highly reactive phenyl-nitrene which spontaneously formed covalent bonds with neighboring hydrocarbons. On these proteins-immobilized polystyrene plates, the liver cancer cells 7402 were cultured under the serum-free conditions, and the inhibition activity on proliferation of liver cancer cells was investigated and analyzed.
Assuntos
Animais , Proteínas de Bactérias , Química , Farmacologia , Materiais Biocompatíveis , Farmacologia , Divisão Celular , Cianobactérias , Química , Neoplasias Hepáticas , Patologia , Fotoquímica , Poliestirenos , Química , Spirulina , Succinimidas , Química , Células Tumorais CultivadasRESUMO
Objective: To investigate the influence of polysaccharide of Spirulina platensis(PSP) on inhibition activity of immobilized phycocyanin (PC) against proliferation of pancreatic cancer cells SW1990. Methods: PSP was added to the wells of cell culture polystyrene which was immobilized with PC, and SW1990 cells were cultured on this kind of biomaterial in serum free medium. Results: When the concentration of PSP was 15 mg/L, the inhibition activity was mainly caused by PSP, and when the concentrations were 10, 17.5 and 25 mg/L, PSP was cooperative with immobilized PC. The best immobilized amount of PC was 0.02 mg/well, which could inhibit 86% SW1990 cells. Conclusion: PSP can enhance the inhibition activity against pancreatic cancer cells SW1990 from immobilized PC.