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I Yamane

Publications and source records attributed to I Yamane.

At least 73 records · Page 4Linked to original sources

Further characterization of porcine plasma fibronectin which contains fucosylated carbohydrate chains.

Porcine plasma fibronectin and its functional four fragments produced by cathepsin B digestion were examined for biological, immunochemical and biochemical properties. Native fibronectin, 150-kDa and 130-kDa fragments exhibited similar cell attachment-promoting activity to each other. In an Ouchterlony double immunodiffusion system, these three polypeptides formed a precipitin line with anti-fibronectin antiserum, while the 50-kDa and 30-kDa fragments did not. The 150-kDa and 130-kDa fragments contained free sulfhydryl(s). The glycopeptide fractions were prepared by pronase digestion of porcine and human plasma fibronectin, and radiolabeled with [14C]acetic anhydride. The results of affinity chromatography with concanavalin A and lentil lectin immobilized on agarose indicated that the porcine glycopeptide fraction was different from the human fraction in that a larger part (58%) of the former was bound to lentil lectin. About 90% of this lentil lectin-reactive glycopeptides lost this reactivity upon alpha-L-fucosidase digestion. The glycopeptide fractions were also prepared from three carbohydrate-containing domains. Less than 30% of the radioactivity of the glycopeptide fractions of 150-kDa and 130-kDa fragments was retained on the lentil lectin-agarose, while about 90% of that from the 50-kDa fragment was retained. These results indicate that porcine plasma fibronectin has characteristics very similar to those of human plasma fibronectin and others, but is unique in that it contains fucosylated carbohydrate chains which unevenly distribute through functional domains.

Animals↗

Biochemical and immunochemical comparison of fibronectin and polynectin from porcine plasma.

Polynectin, a glycoprotein of porcine blood plasma (also known as glycine-rich gelatin-binding protein (Isemura, M., Sato, N., and Yosizawa, Z. (1982) J. Biol. Chem. 257, 14854-14857] is similar to fibronectin with respect to binding characteristics to affinity gels. However, no immunoprecipitation reaction was observed either between polynectin and anti-fibronectin antiserum, or between fibronectin and anti-polynectin antiserum prepared in the present experiments. No cross-reaction was found between fibronectin and polynectin by enzyme-linked immunosorbent assays. Immunohistochemical studies revealed the presence in abundance of polynectin in intestinal and gastric glands. It was found that the pattern of distribution of polynectin was entirely different from that of fibronectin. Polynectin, in contrast to fibronectin, exhibited no cell attachment-promoting effects on BHK-21, a baby hamster kidney cell line, and a cell line of human embryonic lung fibroblasts. In addition, changes in binding characteristics to affinity gels after reduction and alkylation differed between polynectin and fibronectin. Although both proteins appear to have similar carbohydrate chains in view of the similar reactivities with lectins, the results of the present experiments demonstrated that polynectin is entirely different from fibronectin.

Alkylation↗

Effects of ferrous iron and transferrin on cell proliferation of human diploid fibroblasts in serum-free culture.

Iron-free RITC 80-7 defined medium was used to examine effects of ferrous iron and transferrin on cell proliferation of human diploid fibroblasts. Both ferrous iron and holo-transferrin stimulated cell proliferation in the medium, but apotransferrin did not. When 5 g/l human serum albumin (HSA) was added to the defined medium, excellent growth was obtained under hypoxic conditions, whereas a reduction of cellular growth during the culture periods was observed under aerobic conditions. When ferrous iron was added to the HSA medium alone, the reduction in growth increased in proportion to the concentrations, whereas the addition of transferrin prevented this reduction in a concentration-dependent manner. This suggests that the ferrous iron concentration in media causes a reduction in growth under aerobic conditions and transferrin prevents this reduction because it decreases the ferrous iron concentration. Further, serum albumin seems to be a source of iron in media.

Aerobiosis↗

Isolation and characterization of human placenta fibronectin.

Fibronectin was isolated from human placenta tissues and compared with human plasma fibronectin. Placenta and plasma fibronectins had similar amino acid compositions, immunological properties, and cell attachment-promoting activities, but differed in apparent molecular weight on sodium dodecyl sulfate-polyacrylamide gel electrophoresis, which could be accounted for at least partly by the difference in carbohydrate composition. Unlike plasma fibronectin, placenta fibronectin failed to form a precipitin line with concanavalin A in a double diffusion system. The non- or low-reactivity of placenta fibronectin with this lectin was also demonstrated by affinity chromatography with concanavalin A-agarose, in which more than 90% of the radiolabeled glycopeptides derived from placenta fibronectin was not retained on the gel. The two fibronectins also differed in the reactivity with Lens culinaris agglutinin of their glycopeptide fractions. These data indicate that placenta and plasma fibronectins are different in their carbohydrate structures and, therefore, suggest the presence of a tissue- or cell-specific mechanism for processing the carbohydrates of this glycoprotein.

Amino Acids↗

Primary culture of human esophageal epithelial cells.

Primary cultures and serial passages of nontumorous adult human esophageal epithelial cells derived from surgically resected esophagi of patients with esophageal cancer have been developed. Disaggregated cells obtained by means of tryptic digestion lasting for 90 min grew to confluency in medium RITC 80-7 supplemented with 10% fetal bovine serum (FBS). Such primary cultures were established from more than 20 donors, and could be passaged 3 to 5 times. Fibroblastic contamination was almost eliminated by careful sampling, and it was possible to perform the growth response or serial passages without fibroblastic overgrowth. Serum-free medium RITC 80-7 supplemented with fibronectin (FN) and bovine serum albumin (BSA) also supported the growth of esophageal epithelial cells, but was not sufficient for serial passages. Among growth promoting factors in medium RITC 80-7, the epidermal growth factor (EGF) was highly stimulatory to growth. Insulin, transferrin, FN and BSA also enhanced cell growth and/or attachment. The epithelial nature of the cultured cells was confirmed by transmission electron microscopy and indirect immunofluorescent staining with antikeratin antibody. The majority of the cultured cells were diploid.

Adult↗

Effects of ceruloplasmin and the haptoglobin-hemoglobin complex on the oxygen-dependent reduction in growth of human diploid fibroblasts in serum-free, albumin containing medium.

We examined that growth-promoting activity of two different human albumin (HSA) preparations for human diploid fibroblasts in serum-free RITC 80-7 medium. The activity of one preparation (sample A) was affected markedly by environmental oxygen, whereas the other (sample B) was little affected. Sample B contained ceruloplasmin (Cp) and haptoglobin (Hp) as impurities. To detect the generation of superoxide anion in the media the amount of reduction of cytochrome c that is inhibited by superoxide dismutase (SOD) was determined. In an aerobic environment it was relatively large in comparison with reduction inhibited in a hypoxic environment. Reduction in the sample A with HSA-supplemented medium was relatively large in comparison with that in sample B with HSA-supplemented medium. The reduction of cytochrome c also was inhibited by Cp (25 mg/l) and catalase (4000 units/ml). Moreover, SOD, Cp, catalase and Hp.Hb (but not Hp) partially prevented oxygen-dependent reduction in growth in an aerobic environment when added to sample A HSA-supplemented medium. These results suggest that Cp and Hp.Hb act as an antioxidants in culture.

Blood Protein Electrophoresis↗

Differential growth requirements of serum factors (bovine serum albumin and low density lipoprotein) for normal and transformed human cells in a serum-free culture.

Serum-free culture is a useful method for identifying the growth requirements of normal cells of human origin and comparing them to the requirements of transformed human cells. We examined differential growth requirements of serum factors (bovine serum albumin (BSA) and low density lipoprotein (LDL) on normal (HEL), Co-60 gamma ray-transformed (CT-1) and 4-nitroquinoline 1-oxide-transformed (SUSM-1) human fibroblast cells in the absence of serum. A decreased requirement for serum was closely related to a decreased requirement for BSA in both types of transformed cells. The growth rate and saturation density of HEL and CT-1 cells grown in serum-free medium supplemented with the optimal concentrations of BSA were almost equal to the rates of cells grown in serum-supplemented medium. When BSA alone was added to the serum-free medium it did not support the continuous growth of SUSM-1 cells because of cellular detachment. An addition of LDL to serum-free cultures not only promoted the moderate growth of HEL cells, it promoted the continuous growth of SUSM-1 cells as well. In contrast, LDL was not required for the optimal growth of CT-1 cells. Transformed human cells specifically had reduced quantitative and qualitative growth requirements for one or more serum factors.

Blood↗

Oxygen-dependent growth declining and effect of vitamin E for human diploid fibroblasts in serum-free, BSA-containing culture.

Growth promoting activity of bovine serum albumin for human diploid fibroblasts was affected by oxygen environment. When cells (2 X 10(4) cells/35 mm dish) were cultured with BSA of 5 g/liter supplemented RITC 80-7 under hypoxic (7%) environment, excellent growth was maintained during the period of culture, while the growth under aerobic environment markedly declined after 3 days of culture. The culture challenged with BSA under aerobic environment generated a relatively large amount of malondialdehyde (MDA) as a product of lipid peroxidation. Vitamin E restored the declining of growth and inhibited MDA formation. Also in vitro lifespan of the cells challenged with BSA markedly decreased under aerobic environment as compared with that of the cells under hypoxic environment. Vitamin E did not restore the oxygen-dependent decreasing of in vitro lifespan. On the other hand, the cells cultured with serum supplemented medium grew and phased out similarly under both oxygen environment as well as the case with BSA supplemented RITC 80-7 under hypoxic environment. These results suggest that the extent of cell proliferation is controlled in part by lipid peroxidation and serum antioxidant activity is not identical from that of vitamin E.

Blood↗

Cultivation of V79 cells in serum-free medium containing bovine serum albumin and the use of gelatin as an attachment factor.

V79 cells were cultivated in a serum-free medium. When a serum-free, bovine serum albumin-containing medium was used, removal of trypsin after cell detachment during subcultivation was necessary for routine mass cultivation. For colony formation addition of an attachment factor to the medium was further necessary. Gelatin was proved to serve as a good attachment factor in the colony formation and it could be substituted for fibronectin as an attachment factor for serum-free cultivation of many types of cells.

Animals↗