Epithelial cells, in tissue culture

Small-scale in vitro test systems may now be employed to assess biopharmaceutical properties or the drug s potential behaviour after in vivo administration. For example, drug penetration through monolayers of epithelial cells in tissue culture can be used to examine bioavailability. The drug s metabolism can be studied in vitro using hepatic microsomes and potentially toxic metabolites identified before problems arise in vivo Although not absolute, these tests... 

Katsuta, H. and Takaoka, T. (1975). Chemical carcinogenesis of mammalian epithelial cells in tissue culture, Cancer Res. 17,59. 

Gstraunthaler GJ. Epithelial cells in tissue culture. Ren Physiol Biochem 11 1-42,1988. 

Fuchs S, Hollins AJ, Laue M, Schaefer UF, Roemer K, Gumbleton M, Lehr CM (2003) Differentiation of human alveolar epithelial cells in primary culture— Morphological characterisation and expression of caveolin-1 and surfactant protein-C. Cell Tissue Res 311 31-45... 

Isolated animal cells in tissue culture, no matter how highly differentiated, tend to revert quickly to one of three basic types known as epitheliocytes, mechanocytes, and amebocytes. Epitheliocytes are closely adherent cells derived from epithelial tissues and thought to be related in their origins to the two surface layers of the embryonic blastula. Mechanocytes, often called fibroblasts or fibrocytes, are derived from muscle, supporting, or connective tissue. Like the amebocytes, they arise from embryonic mesenchymal tissue cells that have migrated inward from the lower side of the blastula (Chapter 32). Neurons, neuroglia, and lymphocytes are additional distinct cell types. 

Livny, O., Kaplan, I., Reifen, R., Polak-Charcon, S., Madar, Z., and Schwartz, B. 2003. Oral cancer cells differ from normal oral epithelial cells in tissue like organization and in response to lycopene treatment An organotypic cell culture study. Nutr. Cancer 47, 195-209. 

Gstraunthaler G, Seppi T, Pfaller W (1999), Impact of culture conditions, culture media volumes and glucose content on metabolic properties of renal epithelial cell cultures. Are renal cells in tissue culture hypoxic , Cell. Physiol. Biochem. 9 150-172. 

Figure 6, Polarized epithelial cells in culture. Epithelial cells in culture possess an apical surface with microvilli that faces the tissue culture medium (equivalent to the lumenal side of the cells in vivo), and a basolateral surface that faces the tissue culture dish (equivalent to the blood side of the cells in vivo).

Jumarie Cand Malo C (1991) CACO-2 cells cultured in serum-free medium as a model for the study of enterocytic differentiation in vitro. J Cell Physiol 149 24-33 Karlsson J, Ungell AL, Artursson P (1994) Effect of an oral rehydration solution on paracellular drug transport in intestinal epithelial cells and tissues assessment of charge and tissue selectivity. Pharm Res 11 248... 

Both calcidiol and calcitriol are substrates for24-hydroxylation, catalyzed by a cytochrome P4so-dependent enzyme in kidneys, intestinal mucosa, cartilage, and other tissues that contain calcitriol receptors. This enzyme is induced by calcitriol the activities of calcidiol 1-hydroxylase and 24-hydroxylase in the kidney are subject to regulation in opposite directions, so that decreased requirement for, and synthesis of, calcitriol results in increased formation of 24-hydroxycalcidiol. Kidney epithelial cells in culture show increased formation of 24-hydroxycalcidiol, and decreased formation of calcitriol, after the addition of calcitriol or high concentrations of calcium to the culture medium. 

It was found that a keratinase from Streptomyces fradiae had the greatest elastase activity of any of the enzyme preparations tested. A similar line of thought recently led Fiizi et al. (1960) to examine the use of elastase for the isolation of cells during tissue culture. The effect of pancreatic elastase in separating the cells for the preparation of cell suspensions was examined. It was found that pancreatic elastase solutions in phosphate buffer were effective within 3-10 min for rabbit epithelial cell cultures and human amnion epithelial cell cultures. The toxicity of the elastase preparations towards the cells did not appear to exceed that of trypsin. 

Ohishi I, Hama Y (1992) Purification and characterization of heterologous component lls of botulinum C2 toxin. In Microbiol Immunol. 36 221 -9 Ohishi I, Iwasaki M, Sdkaguchi G. (1980) Purification and characterization of two components of botulinum 02 toxin. In Infect Immun. 30 668-73 Ohishi I, Miyake M (1985) Binding of the two components of 02 toxin to epithelial cells and brush borders of mouse intestine. In Infect Immun. 48 769-75 Ohishi I, Tsuyama S (1986) ADP-ribosylation of nonmuscle actin with component I of 02 toxin. In Biochem Biophys Res Comm. 136 802-6 Ohishi I, Yanagimoto A (1992) Visualizations of binding and internalization of two nonlinked protein components of botulinum 02 toxin in tissue culture cells. In Infect Immun. 60 4648-55... 

Over the last decades, cell and tissue cultures of renal epithelial cells have become powerful tools to study basic renal physiological functions, including transport, metabolism, and the effects of external stimuli such as oxygen tension, nutrition, hormones, and xenobiotics. Indeed, cultured renal tubular epithelial cells were one of the first cells utilized for investigating drug-induced injury. In this chapter, we describe the methods used to isolate different types of renal cells, aspects of primary cell culture, and tools to immortalize primary cells. We summarize the desired characteristics of various renal cell types and review the most widely used. Finally, we address important aspects of renal cell culture. 

When rats are placed on a high-fat diet, the intestinal mucosa and the blood become enriched with alkaline phosphatase (F19, F20, Ml, M2). That the striated borders of the absorptive epithelial cells in rats possess the L-phenylalanine-sensitive alkaline phosphatase was proven by Watanabe and Fishman (W7). Human intestinal cells grown in tissue culture (W7) and human intestine exhibit L-phenylalanine sensitivity. Phosphatase has long been found to be present in feces (L8). 

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