Kidney epithelial cells

A good example of the problems encountered with the use of serum with primary cultures is illustrated by the case with cultured kidney cells. The kidney epithelial cell line MDCK grows in serum-free medium supplemented with five supplements ... 

Figure 10. Primary cultures of mouse kidney cells. Primary cultures of kidney epithelial cells derived from 10-day-old mice were grown either in hormonally defined medium with five supplements (5 pg/ml insulin, 5 pg/ml transferrin, 25 ng/ml PCE, 5 X10" M hydrocortisone, and 5 x 10" M Tj), or in medium supplemented with 10% fetal calf serum. After 10 days, primary cultures still were epithelial in morphology serum free (a) but were overgrown with fibroblasts with serum (b). (Taub et al., 1979 with permission.)...

Taub, M. Sato, G. (1980). Growth of functional primary cultures of kidney epithelial cells in defined medium. J. Cell. Physiol. 105, 369-378. 

Taub, M., Chuman, L., Saier, M.H., Sato, G. (1979). Growth of a kidney epithelial cell line (MDCK) in hormonally defined serum-free medium. Proc. Natl. Acad. Sci. USA 76, 3338-3342. 

N., Komano, T., Hori, R., Transport of digoxin by human P-glycoprotein expressed in porcine kidney epithelial cell line (LLC-PK1), J. Pharmacol. Exp. Ther. 1992, 263, 840-845. 

The presence of a transporter can be assessed by comparing basolateral-to-apical with apical-to-basolateral transport of substrates in polarized cell monolayers. If P-gp is present, then basolateral-to-apical transport is enhanced and apical-to baso-lateral transport is reduced. Transport experiments are in general performed with radioactively labeled compounds. Several studies have been performed with Caco-2 cell lines (e.g. Ref. [85]). Since Caco-2 cells express a number of different transporters, the effects measured are most probably specific for the ensemble of transporters rather than for P-gp alone. P-gp-specific transport has been assayed across confluent cell layers formed by polarized kidney epithelial cells transfected with the MDR1 gene [86], Figure 20.11 shows experimental data obtained with these cell lines. A rank order for transport called substrate quality was determined for a number of compounds [86]. The substrate quality is a qualitative estimate, but nevertheless allows an investigation of the role of the air/water (or lipid/water) partition coefficient, log Kaw, for transport as seen in Fig. 20.11(A). For most of the compounds, a linear correlation is observed between substrate quality and log Kaw- However, four compounds are not transported at all despite their distinct lipophilicity. A plot of the substrate quality as a function of the potential of a... 

Servent and colleagues [52] reported that GTN is metabolised in rat liver microsomes by an NADPH-dependent cytochrome P-450 system, yielding GDN, glyceryl mononitrate (GMN) and NO. Moreover, Schroeder and Schroer [53] showed that inhibitors of cytochrome P-450 reduce cGMP stimulation by GTN in kidney epithelial cells. 

Inhibitors of cytochrome P-450 reduce cyclic GMP stimulation by glyceryl trinitrate in LLC-PKi kidney epithelial cells. Naunyn Schmiedebergs Arch. Pharmacol. 342 (1990), p. 616-618... 

The studies on phospholipid bilayers with defined amounts of charged component are helpful to explain the partition characteristics in biological membranes. Liposome water partition data of propranolol in lipids from kidney epithelial cells (a common model system in pharmaceutical sciences for the uptake into the gastrointestinal tract) have been successfully described with partition models developed for pure bilayers or defined mixtures [159]. Since lipophilic cations and anions can be used as probes for the membrane potential, their interaction with microbial and mitochondrial membranes has been studied... 

Mercury is known to exert an effect on the synthesis of membrane lipids. Mercuric chloride produces lipid alteration in pig kidney epithelial cells (LLC-PK, cells), with rapid accumulation of unesterified fatty acids (particularly arachidonic acid) and lysophospholipids and loss of cellular phospholipids... 

Cherian, M.G. (1982). Studies on toxicity of metallothionein in rat kidney epithelial cell culture. Dev. Toxicol. Environ. Set 9 193-202. 

Detrisac, C.J., Sens, M.A., Garvin, A.J., Spicer, S.S. and Sens, D.A. (1984). Tissue culture of human kidney epithelial cells of proximal tubule origin. Kidney Int. 25 383-390. 

Ford, S.M., Bennett, D., Laska, D.A., Tay, L.K. and Williams, P.D. (1987). Biochemical comparison of fresh kidney homogenates, rabbit primary proximal tubule cultures (RPT), and a rabbit kidney epithelial cell line (LLC-RIG). FASEB J., April, 1987. 

Inui, K., Saito, H. and Hori, R. (1985). H+ gradient-dependent active transport of tetaethyl-ammonium cation in apical-membrane vesicles isolated from kidney epithelial cell line LLC-PK Biochem. J. 227 199-203. 

McLachlin, J.R., Goyer, R.A. and Cherian, M.G. (1980). Formation of lead-induced inclusion bodies in primary rat kidney epithelial cell cultures effect of actinomycin D and cycloheximide. Toxicol. Appl. Pharmacol. 56 418-431. 

MDCK Dog kidney epithelial cells Polarized cells with low intrinsic expression of transporters Suitable cell fine for transfections... 

LLC-PK1 Cells derived from pig kidney epithelial cells (LLC-PK1) have been used as an alternative to Caco-2 cells for assessing the permeability for test compounds [153, 85], LLC-PK1 cells are more easily transfected than Caco-2 cells. Especially the LLC-PK1 line stably transfected with P-gp/MDRl has been reported as a tool to study bidirectional transport of compounds [142, 58, 180],... 

Other cell lines used in permeability studies include the T84 human colonic adenocarcinoma colonic crypt cell model. This line has a reduced carrier expression, secrets mucus, and has very high resistance [31, 32], The IEC cell line is a rat fetal intestinal epithelium cell with higher permeabilities than Caco-2 cells [33], LLC PKi is a pig kidney epithelial cell line with low expression of efflux systems, but expression systems for transport proteins [32], 2/4/A1 cells are a conditionally immortalized rat fetal intestinal epithelium line with crypt cell-like morphology and temperature-sensitive differentiation [34], They form differentiated monolayers with tight junctions, increased brush border enzymes when grown on extracellular matrices with laminin. Transport of drugs with LP in 2/4/A1 monolayers was comparable to that in the human jejunum and up to 300 times faster than that in Caco-2 monolayers. In contrast, the permeability of HP drugs was comparable in both cell lines [34],... 

Shitara Y, Kato Y, Sugiyama Y. Effect of brefeldin A and lysosomotropic reagents on intracellular trafficking of epidermal growth factor and transferrin in Madin-Darby canine kidney epithelial cells. J Control Release 1998 55(1) 35 3. 

A series of specific H+-linked cotransporters are found in the brush border membranes of small intestine and in kidney epithelial cells.440 441 In green plants H+-linked cotransport of amino acids is used in the distribution of amino acids synthesized in the roots and leaves to other parts of the plants.442 443... 

Figure 12.9 Endothelial cell-specific nuclear import of plasmids. Growth-arrested African Green Monkey kidney epithelial cells (TC7), human pulmonary artery smooth muscle cells (HSMCs) and human umbilical vein endothelial cells (HUYECs) were microinjected in the nucleus (top) and cytoplasm with CMV-driven, GFP-expressing plasmids containing either no additional sequences (open bars), the SV40 enhancer (striped bars), or the flk-1 promoter (shaded bars). Eight hours after injection, the cells were visualized for GFP expression by fluorescence microscopy. Whereas all three plasmids supported GFP expression when delivered into the nucleus of all three cell types, only the SV40 enhancer mediated nuclear import and gene expression in all cells when injected into the cytoplasm. As predicted, the flk-1 promoter caused import and expression only in cells in which transcription factors necessary for its expression and import were made, namely endothelial cells.

Monkey kidney epithelial cells (TC7), human pulmonary artery smooth muscle cells... 

PKD involves abnormal proliferation and differentiation of kidney epithelial cells, resulting in the formation of cysts that eventually destroy the kidneys in affected individuals. Together, PCI and 2 appear to form a complex that senses the state of the kidney epithelium as an early step in a pathway that controls epithelial... 

The ratio of renal clearance of digoxin to creatinine clearance decreased with the coadministration of clarithromycin (0.64 and 0.73), and was restored (1.30) after administration of clarithromycin had stopped (326). The role of P-gp efflux in this interaction was confirmed using an in vitro kidney epithelial cell line (326). The administration of itraconazole, a P-gp inhibitor, with digoxin resulted in an increased trough concentration and a decrease in the amount of renal clearance, possibly by an inhibition of the renal tubular secretion of digoxin via P-gp (329). The P-gp modulator verapamil has also been shown to decrease the renal clearance of digoxin (330). 

Nagai J, Takano M, Hirozane K, et al. Specificity of p-aminohippurate transport system in the OK kidney epithelial cell line. J Pharmacol Exp Ther 1995 274 (3) 1161-1166. 

Fig. 2 Left cytoplasmic microtubules in interphase kidney epithelial cells imaged with the fluorescent paclitaxel derivative Flutax-2 (green) and nuclear DNA stained with Hoescht 33342 (blue). Right mitotic spindle from a dividing metaphase cell with similarly imaged microtubules and chromosomes. Bars indicate 10 pm (micrographs courtesy of Isabel Barasoain)...

M. J. Cho, I. F. Scieszka. C. T. Cramer, D. P. Thompson, and T. J. Vidinac Neutrophil-mediated transport of liposomes across the Madin Darby canine kidney epithelial cell... 

ADA BEVS BHK CHO ELISA mAb MDCK MMR SCID tPA VLP adenosine deaminase deficiency baculovirus expression vector system baby hamster kidney cell line Chinese hamster ovary cell line enzyme linked immuno sorbent assay monoclonal antibodies Madin-Darby canine kidney epithelial cells measles, mumps, rubella severe combined immunodeficiency plasminogen activator virus-like particle... 

One of the major problems in establishing cultures of epithelial cells is the overgrowth of these cells by the faster growing fibroblasts and serum-free media have been devised which do not permit fibroblast growth, thus allowing cultures of mouse kidney epithelial cells to be obtained (Taub et al., 1979 Taub and Sato, 1980) (Fig. 

Yamasaki F, Tomoaki S, Watanabe M, Mizota M. Uptake of human urinary trypsin inhibitor by the kidney epithelial cell line, LLC-PK1. Pflugers Arch 1996 433 9-15. 

HEK293 cells from Homo sapien embryonic kidney epithelial cell line transformed with adenovirus 5 DNA and maintained in cell culture incubators In vitro... 

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. 

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