The MDCK cell line was initiated in 1958 by S. H. Madin and N. B. Darby from the kidney tissue of an adult female cocker spaniel. The cells exhibit typical epithelial morphology and stain positive for keratin.

MDCK cells demonstrate susceptibility to a number of viruses, including infectious canine hepatitis, coxsackievirus B5, reoviruses 2 and 3, vesicular stomatitis (Indiana strain), adenoviruses 4 and 5, vesicular exanthema of swine, and vaccinia. The cells, which are negative for the enzyme reverse transcriptase, are known to be resistant to poliovirus 2 and coxsackieviruses B3 and B4. The MDCK line is a popular tool for studies focusing on the processing of beta-amyloid precursor protein and its proteolytic products.

MDCK cells are also frequently utilized as a general model for epithelial cells. In the body, epithelial cells are tightly packed into contiguous sheets called epithelia. The cells that comprise an epithelial sheet are linked together by unique specialized junctions called tight junctions. Epithelial sheets function in a number of ways, but are especially important as barriers to the diffusion of various molecules. The epithelial cells that line the kidneys also are involved in the temporary storage and secretion of wastes. In culture, epithelial cells tend to experience strong contact inhibition of migration and form monolayers similar to the epithelial sheets that occur in vivo.

Epithelial cell tight junctions and nuclear pore complex proteins were simultaneously imaged in a culture of Madin-Darby canine kidney cells with a cocktail of rabbit anti-ZO-3 and mouse anti-NPCP primary antibodies, followed by goat anti-rabbit and anti-mouse secondary antibodies conjugated to Alexa Fluor 568 and Alexa Fluor 488, respectively. Images were recorded in grayscale with a 12-bit digital camera coupled to either a Nikon E-600 or Eclipse 80i microscope equipped with bandpass emission fluorescence filter optical blocks. During the processing stage, individual image channels were pseudocolored with RGB values corresponding to each of the fluorophore emission spectral profiles.

Distribution of Keratin Intermediate Filaments in Madin-Darby Canine Kidney Cells - The adherent log phase culture of MDCK cells presented in this section was treated for one hour with MitoTracker Red CMXRos in order to label the mitochondrial network, and the fixed cells were then incubated with mouse anti-cytokeratin primary antibodies followed by goat anti-mouse secondary antibodies (IgG) conjugated to Cy2. Nuclei were counterstained with Hoechst 33258.

Targeting Histones and Peroxisomes in MDCK Cell Cultures with Immunofluorescence - Cultured Madin-Darby canine kidney cells were fixed, permeabilized, blocked with 10 percent normal goat serum, and treated with a cocktail of mouse anti-histones (pan) and rabbit anti-PMP 70 (peroxisomal membrane protein) primary antibodies, followed by goat anti-mouse and anti-rabbit secondary antibodies (IgG) conjugated to Texas Red and Alexa Fluor 488, respectively. The cytoskeletal filamentous actin network was counterstained with Alexa Fluor 350 conjugated to phalloidin.

Visualizing Tight Junctions and Nuclear Pore Complex Proteins in Canine Kidney Epithelial Cells - Simultaneous localization of tight junctions and nuclear pore complex proteins (NPCP) was performed in a double immunofluorescence experiment with a MDCK cell culture using mouse anti-NPCP and rabbit anti-ZO-3 primary antibodies. The subcellular targets were visualized using goat anti-mouse and anti-rabbit secondary antibodies (IgG) conjugated to Alexa Fluor 488 and Alexa Fluor 568, respectively.

Enhanced Yellow Protein Subcellular Localization of Mitochondria in MDCK Cell Cultures - The culture of Madin-Darby canine kidney epithelial cells illustrated in this section was transfected with a pEYFP-Mitochondria chimeric plasmid subcellular localization vector. The cells were also stained with SYTOX Orange, targeting DNA in the cell nucleus.

Targeting Mitochondria with Primary Antibodies in Madin-Darby Canine Kidney Cells - The adherent monolayer culture of Madin-Darby canine kidney cells featured in this section was immunofluorescently labeled with a primary mouse anti-oxphos complex V inhibitor protein antibody, followed by goat anti-mouse Fab fragments conjugated to fluorescein. The culture was subsequently stained with Alexa Fluor 568 conjugated to phalloidin to reveal details of the filamentous actin network, and DAPI for DNA in the nucleus.