Traditional animal models to quantify the degree of blood vessel formation are being replaced by cell culture assays
that are easier to set up, statistically reliable and can be automated in a drug screening laboratory. These assays rely on the endothelial cells’ ability to form distinct blood-vessel-like tubules in an extracellular matrix where they can subsequently be visualized by fluorescence microscopy. - [Read An Image-Based Assay of Endothelial Cell Tube Formation as a Model of Angiogenesis]
The technique of JC-1 staining has been developed with the intent to detect DY in intact, viable cells. For this purpose JC-1 acts as a marker of mitochondrial activity, since the formation of J-aggregates, which give red emission, is reversible. Cells with high DY are those forming J-aggregates, thus showing high red fluorescence. On the other hand, cells with low DY are those in which JC-1 maintains (or re-acquire) monomeric form, thus showing only green fluorescence. - [Read Analysis of Mitochondrial Membrane Potential with the Sensitive Fluorescent Probe JC-1]
Protocol describes the use of a basic water-based dye to stain for acid mucosubstances and acetic mucins located on the cartilage of fixed embryos, permitting the examination of cartilage formation. - [Read Cartilage Staining of Xenopus tropicalis Protocol]
Fractionation of (a) vacuolar and subvacuolar vesicles and (b) vacuole and cytoplasm-to-vacuole targeting (Cvt) vesicles from yeast spheroplasts in a pre-formed discontinuous iodixanol gradients. Protocol includes: Formation of yeast spheroplasts; Isolation and vesiculation of the vacuoles; Separation of the vacuolar and subvacuolar vesicles; Separation of vacuoles and Cvt vesicles from a yeast spheroplast lysate. - [Read Fractionation of Vacuolar and Subvacuolar vesicles and Vacuole and Cytoplasm-to-Vacuole Targeting]
Protocol describes an assay that relies on the endothelial cells’ ability to form distinct blood-vessel-like tubules in an extracellular matrix where they can subsequently be visualized by fluorescence microscopy. Although quantification of the tubules can be performed by manual tracing, this method precludes the use of the assay in unbiased high-throughput applications. - [Read Image Based Assay of Endothelial Cell Tube Formation Protocol]
For many sources of antigens, one useful method of lysis is to treat cells with harsh, denaturing solutions to release most of the protein antigens, as described here. The lysates are then diluted to reduce the denaturing conditions to levels that are suitable for the formation of antibody-antigen complexes. The resulting solution is precleared prior to immunoprecipitation. - [Read Immunoprecipitation: Denaturing Lysis Protocol]
Leukostat Staining of Cytospin Preparations to Detect Apoptosis. Shailaja Kasibhatla et al. Leukostat staining is used to visualize nuclear changes and apoptotic body formation that are characteristic of apoptosis. Cells are viewed under a light microscope and counted to quantify apoptosis. This protocol can be used both for cells that grow in suspension and for adherent cells. - [Read Leukostat Staining of Cytospin Preparations to Detect Apoptosis]
This protocol describes the isolation of microsomal Endoplasmic Reticulum (ER) membranes from yeast cells. Includes: Spheroplast Formation and Microsome Purification. - [Read Microsome Preparation from Yeast Cells Protocol]
This protocol describes the preparation of polyethylenimine (PEI)/DNA nanoparticles for targeted gene delivery. This delivery strategy improves the efficiency of gene transfer by enhancing the entry of gene vectors into the desired cells and reducing uptake by nontarget cells. We describe here methods for the conjugation of targeting peptides to PEIs, formation of DNA complexes using the conjugated PEIs or nonconjugated PEIs together with targeting peptides, and cell transfection. - [Read PEI Nanoparticles for Targeted Gene Delivery Protocol]
Early embryos (0-17 hours or until cuticle formation) are treated with a mixture of organic solvents, formaldehyde, and alcohols, as described here. The cuticles of late-stage embryos are usually opened by sonication. Tissues from more advanced stages of development are normally dissected by hand and then fixed and stained in a standard paraformaldehyde/detergent combination - [Read Preparing Early Whole-Mount Drosophila Embryos for Immunostaining Protocol]
Includes protocols: Mouse Embryonic Fibroblasts (MEF) Preparation; Harvesting MEFs; Cryopreservation of MEFs; Thawing and maintaining MEFs; Irradiating & Plating MEFs; Culture of Human ES cells with Matrigel® and Conditioned
Medium; Preparation of Conditioned Medium (CM); Preparation of Matrigel® -coated plates; Passage of human ES cells on Matrigel®; Daily maintenance of feeder-free culture; Freezing Human ES Cells; Thawing Human ES cells; Formation of Embryoid Bodies; - [Read Protocols for the Maintenance of Human Embryonic Stem Cells in Feeder Free Conditions]
Protocol for myelin sheath. Luxol Fast Blue is the alcohol soluble counterpart of the water soluble Alcian Blue. Staining is due to lipoproteins, and the mechanism is one of an acid-base reaction with salt formation; the base of the lipoprotein replaces the base of the dye. - [Read Staining for Myelin Sheath Protocol]
Tubulin is polymerized into microtubules by incubating tubulin at 37°C with GTP. A nucleation seed is added when the purpose is to assay microtubule elongation. Tubulin can also be polymerized for the purposes of recycling the tubulin or labeling the microtubules with fluorescently labeled tubulin. Based on the protocol by Timothy Mitchison of Harvard University.
The DNA Ligation protocol described here contains the steps required to join together using ligase enzyme both plasmid DNA and insert DNA fragments in order to create a new plasmid. This new ligated plasmid can be transformed after into competent bacteria to produce DNA for mini, midi or maxi-prep isolation.
This protocol a protocol on how to generate transfected embryonic stem (ES) cell clones. The previous protocol in this series is the Protocol for Electroporation of ES cells. The next protocol in the series is the Protocol on Disaggregation, Expansion, and Freezing of Transfected ES Clones.
This protocol describes the electroporation of the BMH 81-17 mut S strain that is recommended for tranformation of the site directed mutagenesis of dsDNA (See Protocol on Site-Directed Mutagenesis on Double Stranded DNA). BMH 81-17 mut S are a mismatch repair defective (mut S) Escherichia coli strain. The probability that the two mutations will cosegregate during the first round of DNA replication is increased in this strain.