OBJECTIVETo study the expression of alpha5beta1 integrin in the abnormal scars and its role and significance in the formation and development of abnormal scars.

METHODSThe expression of alpha5beta1 integrin was observed in hypertrophic scar (15 samples), keloid (15 samples) and normal skin (10 samples) with SP immunohistochemical method and colloidal gold immuno-electron microscopic technique. The data were semi-quantitatively analyzed.

RESULTSThe expression levels of alpha5beta1 integrin in the fibroblasts of keloids and hypertrophic scars were higher than normal skin; the expression of alpha5beta1 integrin in the fibroblasts of keloids was higher than hypertrophic scars (P < 0.01).

CONCLUSIONThe alpha5beta1 integrin appears to have close relation to the formation and development of abnormal scars. To find a way to decrease the expression level of alpha5beta1 integrin in fibroblasts may be a new approach to inhibit scar hypertrophy.

Cicatrix ; metabolism ; pathology ; Humans ; Immunohistochemistry ; Integrin alpha5beta1 ; analysis ; metabolism ; Keloid ; metabolism ; pathology ; Microscopy, Immunoelectron ; Skin ; chemistry ; pathology ; ultrastructure

By using the cell density, cell viability, size distribution of cell aggregates,specific consumption rate of glucose (q_ glc ), specific production rate of lactate (q_ lac ), lactate transform rate (Y_ lac/glc ) and amino acids utilization as the evaluation indexes, the growth and metabolism of HEK293 cells under carrier-free immobilization culture mode were examined and compared with those of HEK293 cells cultured in static tissue flasks. It was found that HEK293 cells grown as suspended cell aggregates in spinner flasks maintained the basic growth and metabolism characteristics of HEK293 cells in stationary anchored culture, and HEK293 cells under carrier-free immobilization culture mode as suspended aggregates in stirred bioreactor facilitate perfusion performance and increase unit productivity. Cultivation of HEK293 cells in carrier-free immobilization culture mode has potential for further improving mammalian cells culture technique.

OBJECTIVETo observe the effect of tetrandrine on activity of collagenase derived from human hypertrophic scar for the sake of clarifying the mechanism as tetrandrine acting on scar.

METHODSThe experimental concentration was controlled below that of cell proliferation inhibited, SDS-PAGE electrophoresis was adopted to separate collagenase from extracellular matrix, and then activated by trypsin analyzed the activity of collagenase with density scanning apparatus. At the same time quantity of extracellular collagen was measured using improved chloraseptine T oxidizing assay, moreover analyzed correlation between activity of collagenase and quantity of extracellular collagen.

RESULTSIn the concentration below the lever of inhibiting fibroblast proliferation, the total activity of collagenase could be significantly increased by tetrandrine with dosage-dependence associated with quantity of extracellular collagen reduced, which was much greater than that of triamcinolone.

CONCLUSIONIncreasing activity of collagenase on degradation of collagen even in a lower concentration was one of the mechanisms of tetrandrine treating hypertrophic scar.

Benzylisoquinolines ; pharmacology ; Cell Proliferation ; drug effects ; Cells, Cultured ; Cicatrix, Hypertrophic ; metabolism ; pathology ; Collagenases ; metabolism ; Fibroblasts ; cytology ; Humans

Using the amino acids 1-147 of the yeast transcriptional activator GAL4 as the DNA-binding domain and four tandem repeats of the 12-aa peptide (DALDDFDLDMLG) of the herpesvirus as the activation domain, an artificial transcription factor, GVP4,was constructed via the linkage of the nuclear localization signal sequence of SV40. And then, GVP4 was cloned into expression vector pcDNA3 . 1/Hygro ( + ) . Various amounts of targeting sites of artificial transcription factor were linked to the upstream of promoter CMV in exogenous gene expression vector pcDNA3.1 ( + ) that separately harbored EGFP cDNA and t-PA cDNA.The CHO cells were then co-transfected with GVP4 expression vector and EGFP or t-PA expression vector. The effect of GVP4 on exogenous gene expression was evaluated by measuring the fluorescence intensity of EGFP in CHO cells and the concentration of t-PA in the supernatant. GVP4 showed positive effect on the enhancement of exogenous gene expression in CHO cells integrated with targeting sites of artificial transcription factor. And, CHO cells integrated with 10 targeting sites of GVP4 was more favorable to foreign gene expression, which resulted in 2-3-fold increase in both EGFP and t-PA expressions. These results indicated that artificial transcription factor is potent in the enhancement of exogenous gene expression in mammalian cells.
Amino Acid Sequence ; Animals ; CHO Cells ; Cricetinae ; Cricetulus ; Flow Cytometry ; Gene Expression Regulation ; Genetic Vectors ; genetics ; Green Fluorescent Proteins ; genetics ; metabolism ; Tissue Plasminogen Activator ; genetics ; metabolism ; Transcription Factors ; genetics ; metabolism ; Transcriptional Activation ; Transfection