Madin-Darby canine kidney MDCK

Nelson, W.J. Hammerton, R.W. (1989). A membrane-cytoskeletal complex containing Na, K -AT-Pase, ankyrin, and fodrin in Madin-Darby canine kidney (MDCK cells) Implications for the biogenesis of epithelial cell polarity. J. Cell Biol. 108, 893-902. 

The evaluation of the apparent ionization constants (i) can indicate in partition experiments the extent to which a charged form of the drug partitions into the octanol or liposome bilayer domains, (ii) can indicate in solubility measurements, the presence of aggregates in saturated solutions and whether the aggregates are ionized or neutral and the extent to which salts of dmgs form, and (iii) can indicate in permeability measurements, whether the aqueous boundary layer adjacent to the membrane barrier, Umits the transport of drugs across artificial phospholipid membranes [parallel artificial membrane permeation assay (PAMPA)] or across monolayers of cultured cells [Caco-2, Madin-Darby canine kidney (MDCK), etc.]. 

Typical early in vitro permeability assessments measure the rate of flux of a compound from one side of a barrier to another [54, 55]. The barrier has historically been derived from a cell line, most commonly Caco-2 or Madin-Darby canine kidney (MDCK) cells. In the last several years, there has been substantial work and significant progress in the development of parallel artificial membrane permeability... 

The in vitro system we have been using to study the transepithelial transport is cultured Madin-Darby canine kidney (MDCK) epithelial cells (11). When cultured on microporous polycarbonate filters (Transwell, Costar, Cambridge, MA), MDCK cells will develop into monolayers mimicking the mucosal epithelium (11). When these cells reach confluence, tight junctions will be established between the cells, and free diffusion of solutes across the cell monolayer will be markedly inhibited. Tight junction formation can be monitored by measuring the transepithelial electrical resistance (TEER) across the cell monolayers. In Figure 1, MDCK cells were seeded at 2 X 104 cells per well in Transwells (0.4 p pore size) as described previously. TEER and 14C-sucrose transport were measured daily. To determine 14C-sucrose... 

Cho MJ, DP Thompson, CT Cramer, T Vidmar, JF Scieszka. (1989). The Madin-Darby canine kidney (MDCK) epithelial cell monolayer as a model cellular transport barrier. Pharm Res 6 71-77. 

To reach such a site, a molecule must permeate through many road blocks formed by cell membranes. These are composed of phospholipid bilayers - oily barriers that greatly attenuate the passage of charged or highly polar molecules. Often, cultured cells, such as Caco-2 or Madin-Darby canine kidney (MDCK) cells [1-4], are used for this purpose, but the tests are costly. Other types of permeability measurements based on artificial membranes have been considered, the aim being to improve efficiency and lowering costs. One such approach, PAMPA, has been described by Kansy et al. [5],... 

Some laboratories have found an alternative to the short-term cultures by using cell lines other than Caco-2 cells. The most popular of these is Madin-Darby canine kidney (MDCK) cells, an epithelial cell line from the dog kidney. MDCK cells have been suggested to perform as well as Caco-2 cells in studies of passive drug permeability [56]. These cells have also been used to optimise the conditions for studies of low-solubility drugs [53]. However, as noted previously, the active transport processes of this cell line can be quite different to those of Caco-2 cells [28-30], Another cell line that only requires short-term culture is 2/4/A1, which is a conditionally immortalised rat intestinal epithelial cell line [86]. The 2/4/A1 cell line is discussed in Section 4.3.2.2 below. 

Kinoshita, S., H. Suzuki, K. Ito, K. Kume, T. Shimizu, and Y. Sugiyama. Transfected rat cMOAT is functionally expressed on the apical membrane in Madin-Darby canine kidney (MDCK) cells., Pharm. Res. 1998, 15, 1851-1856... 

Amide 39 is a potent and selective inhibitor of GlyT-1 both in vitro (Ki = 1.79 nM) and in vivo (CSF-glycine ED2oo 3.9 mg/kg, rat, p.o.) but with limited permeability across Madin-Darby canine kidney (MDCK) cell membranes [78]. Optimization led to fused [3.1.0] and [3.3.0] azabi-cyclic analogs 40 (PF-3463275) [78] and 41 [79], respectively. Analogs of both systems demonstrated excellent potency (fC = 1.7-95 nM), and improved permeability, PK, and in vivo efficacy. Spatial working memory... 

Add an aliquot of the DSS or BS3 solution to the reaction medium to obtain a final concentration of 0.5-5mM. Note Simons et al. (1999) successfully used a concentration of 0.5 mM BS3 with Madin-Darby canine kidney (MDCK) cells permanently expressing a GPI-anchored form of growth hormone decay accelerating factor (GH-DAF) to crosslink the protein interaction complexes on the cell surfaces. 

A confluent monolayer of Madin-Darby canine kidney (MDCK) cells was grown in 96-well plates. Serial tenfold dilutions in minimal essential medium were prepared from the aliquots of allantoic fluid taken from the irradiated specimen. These dilutions were applied to MDCK cells and incubated for 48 h at 36 °C in 5% C02. The cells were then washed two times for 5 min with phosphate buffered saline (PBS) and incubated for 1 h with 100 pi of 0.5 mg/ml solution of 3-(4,5-dimethyl-thiazolyl-2) 2,5-diphenyltetrazolium bromide (MTT, ICN Biochemicals Inc., Aurora, Ohio). After lh, the colored deposit was dissolved in 100 pi DMSO, and optical density in the wells was measured on plate reader Victor 1420 (Perkin Elmer, Finland). Based on the data obtained, the infectious titer of the vims was determined as a decimal logarithm of reciprocal to the dilution of the specimen causing destruction of 50% of cells. The inhibiting action of irradiation was evaluated by decreasing the vims titer. 

MDCK Madin-Darby canine kidney (MDCK) cells have received attention as an alternative to Caco-2 cells for permeability measurements. When grown under standard culture conditions, MDCK cells develop tight junctions and form monolayers of polarized cells. The main advantage over Caco-2 cells is the shorter culture time to confluence (3-5 days). The transep-ithelial electrical resistance of MDCK cells is lower than that of Caco-2 cells and thus, closer to the TEER of the small intestine in vivo. The permeability coefficients of hydrophilic compounds are usually lower in Caco-2 cells than in MDCK cells, which is consistent with the lower TEER values for MDCK cell monolayers. The nonhuman (canine) and nonintestinal (renal) origin of MDCK cells is considered as a disadvantage. They have low expression levels of transporter proteins and low metabolic activity [34], MDCK cells that are stably transfected with P-gp/MDRl are often proposed as an alternative for Caco-2 cells to study bidirectional transport of compounds and, more... 

To meet the need of conducting HTS for ADME-Tox properties, many slow and expensive in vivo ADME assays are now being replaced by in vitro cell models. For intestinal absorption, Caco-2 cell lines and Madin Darby canine kidney (MDCK) cell lines are widely used to predict the absorption rate of candidate drug compounds across the intestinal epithelial cell barrier. A number of models for Caco-2 cell permeability and MDCK cell permeability have been reported that predict the oral absorption properties of drugs, mostly limited to small organic molecules. Caco-2 and MDCK permeability are related to "A" and "D" in the ADME-Tox. 

Zanamivir (2) is a potent competitive inhibitor of viral neuraminidase glycoprotein, which is essential in the infective cycle of both influenza A and B viruses. It inhibits a wide range of influenza A and B types in vitro as well as in vivo. The concentrations of inhibiting in vitro plaque formation of influenza A and B virus by 50% in Madin-Darby canine kidney (MDCK) cells were 0.004-0.014 p.mol/L in laboratory-passaged strains, and 0.002-16 p.mol/L in assays of clinical isolates. Due to its low bioavailability, it is delivered by inhalation via the Diskhaler , 10 mg twice daily, or intranasally 2-4 times daily for 5 days. After an intravenous dose of 1 -16 mg, the median elimination half-life was ti/2 = 7 h, the volume of distribution at steady state was Vdss = 16 L, and 90% of the dose was excreted unchanged in the urine. After intranasal and inhaled (dry powder) administration, maximum serum concentrations occurred within 2h and the terminal phase half-lives were 3.4 and 2.9 h, respectively. The bioavailabilities were 10 and 25%, respectively, and 20% after inhalation of zanamivir (2) by nebulizer. 

Further, drug transport through epithelial cells has been studied. For instance, Madin-Darby canine kidney (MDCK) cells have been grown into tight mono-layers on a permeable polycarbonate membrane. This membrane (0.4-p.m pores,... 

Cho MJ, Adson A, Kezdy FJ. Transepithelial transport of aliphatic carboxylic acids studied in Madin Darby canine kidney (MDCK) cell monolayers. Pharm Res 1990 7(4) 325-331. 

Lymphocytes, platelets, endothelial cells, fibroblast, hepatocytes, astrocytes, intestine, Madin-Darby canine kidney (MDCK) cells, tracheal ciliary epithelia, choroid plexus, eye lens, frog skin, frog urinary bladder, Ehrlich ascites tumor cells Activation of KCI cotransport... 

While Caco-2 cells typically require 21 days to become suitable for use, the Madin-Darby Canine Kidney (MDCK) cell line, derived from the dog kidney, typically only requires 3 days. This cell-line may prove to be a useful alternative, as the two cell lines show many common features. More investigation is required into how comparable the two systems are. 

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