title: Changes in cell cultures of bovine corneal endothelium cells as related to donor age and number of passages in vitro.
abstract: Aging changes of the acidic glycosaminoglycans (aGAG) were investigated in bovine corneal endothelium cells grown in vitro, using histochemical methods and the determination of hexosamine and uronic acid. The time interval between trypsination and confluency of the monolayer and the cell counts at different time intervals of the same passage number served as parameters for the proliferation capacity of the cultures. A cell line, derived from the eye of a 1,5 year old cattle showed a low proliferation capacity in the first 9 passages, which increased until the 15th passage, to decrease thereafter until the 29th passage. In cells from eyes aged 11 and 12 years respectively the initial proliferation capacity was very low to reach the same values as in cultures of the young eye at the 10th passage but remained constant thereafter. Chromosome counts showed an increased number of hyperploids in late passages of cells from the aging eye with counts around 4n-8n increased to 17% as compared to 5% in the cells derived from the young eye. The cell densities were increased in cultures of high passage numbers. Histochemically the aGAG were shown in the cell nucleus, and the cytoplasm as well as in the intercellular space. In the nuclei of cells from aging eyes and in late passage cells of the young eye they showed an increased resistance against resting hyaluronidase. The hexosamine and uronic acid values were high in early passages of cultures from the young eye and decreased in late passages of the young eye as well as in early passages of cells from the aging eyes. The changes in the aGAG as well as the changes in the cell proliferation are similar comparing early passage cells of aging eyes to late passage cells of the young eyes. But the aGAG changes are more pronounced in cells of eyes aged in vivo. In the eye the proliferation of the corneal endothelium cells is inhibited. As such these cells provide a useful model to comparing in vivo-aging changes of resting cells to changes of the same cells proliferating in vitro.
mesh_terms: D000375:Aging; D000818:Animals; D002417:Cattle; D002455:Cell Division; D002478:Cells, Cultured; D003315:Cornea / Q000166:cytology* / Q000378:metabolism; D004727:Endothelium / Q000166:cytology / Q000378:metabolism; D006025:Glycosaminoglycans / Q000378:metabolism; D006651:Histocytochemistry; D008253:Macaca mulatta; D008938:Mitosis
chemical_list: D006025:Glycosaminoglycans