title: Comparative analysis of proteoglycans synthesized by chick corneal stromal cells in cell culture and organ culture.
abstract: Proteoglycans (PGs) synthesized by chick corneal stromal cells in cell culture and organ culture were metabolically radiolabelled with [35S]sulfate (for glycosaminoglycans) and [3H]leucine (for core proteins). Media, cell extracts and organ extracts from cultures were chromatographed on DEAE-Sephacel columns and separated into three fractions: the pass-through fraction (Fraction 1: nonsulfated PGs, hardly sulfated PGs, or glycoproteins with some oligosaccharides), the fraction eluted with a low salt concentration (Fraction 2: undersulfated PGs), and the fraction eluted with a high salt concentration (Fraction 3: highly sulfated PGs). The PG compositions of each fraction of cell culture and organ culture were then compared. While the proportions of highly sulfated KSPG in Fractions 3 of medium and cell extract of cell culture were both very low compared with those of medium and organ extract of organ culture, respectively, the proportions of highly sulfated CS/DS PG in Fractions 3 of those of cell culture were higher than those of organ culture. On the other hand, the proportions in the 35S activities of nonsulfated or undersulfated KSPG in Fractions 1 and 2 of medium and cell extract of cell culture were comparable to those of organ culture. Furthermore, the proportions of core proteins of undersulfated KSPG in Fractions 2 were higher in cell culture than in organ culture. These results show that, when the cells are cell-cultured, the degree of sulfation of KS chains decreases markedly, but the syntheses of the glycosaminoglycan backbone and core protein are maintained.
authors.affiliation: RI Center, Faculty of Pharmacy, Meijo University, Nagoya, Japan.
authors.forename: I
authors.initials: I
authors.lastname: Takahashi
authors.forename: S
authors.initials: S
authors.lastname: Sashima
authors.forename: K
authors.initials: K
authors.lastname: Nakazawa
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D002645:Chickens; D003315:Cornea / Q000378:metabolism*; D007930:Leucine / Q000378:metabolism; D008297:Male; D009924:Organ Culture Techniques; D011509:Proteoglycans / Q000096:biosynthesis* / Q000378:metabolism; D017154:Stromal Cells / Q000378:metabolism*; D013462:Sulfur Radioisotopes / Q000378:metabolism
chemical_list: D011509:Proteoglycans; D013462:Sulfur Radioisotopes; D007930:Leucine