This protocol describes a stepwise procedure to prepare nucleic acids encapsulated in a polyethylene glycol (PEG)-shielded nanolipoparticle (NLP) that contain a bioresponsive lipid and ligand. This process provides several advantages for systemic gene delivery. The in vivo circulation time is extended. Also, low pH-sensitive lipids enhance DNA unpacking and endosomal escape. Finally, ligands inserted into the NLP surface can target gene delivery to specific tissues or cells in vivo. - [Read Bioresponsive Targeted Charge Neutral Lipid Vesicles for Systemic Gene Delivery Protocol]
Protocol should be viewed as a starting point for systematic optimization of transfection mediated by lipofecting agents. Once a positive signal has been obtained from a transfected plasmid carrying a standard reporter gene, optimal conditions for transfection can be established by systematic variation of parameters such as the initial cell density, the amount and purity of DNA, the media and serum, and the time of exposure of the cells to the cationic-lipid-DNA complex. - [Read DNA Transfection Mediated by Lipofection Protocol]
Accumulation of lipophilic substances in the plasma membrane may affect the membrane lipid order and consequently affect the function of these proteins. Changes in the activity of the Na+/K+ -ATPase, which is the major active transport system responsible for the electrochemical potential in mammalian cells, can therefore be an indication of the effect that a chemical may have on the viability of the cell membrane and possibly the whole cell. - [Read Hamster Ovary Cell NA+/K+ -ATPase Test]
Removal of CCR5 ligands and induction of pro-resolving lipid mediators by apoptotic neutrophils during resolution. Application of lipid extraction from peritoneal exudates, in tandem with lipid mediator informatics can be used to determine the role of apoptotic neutrophils in the generation of resolution phase lipid mediators. This neutrophil transfer system allows the determination of the direct impact of apoptotic leukocytes in the resolution of inflammation. - [Read Removal of CCR5 Ligands and Induction of Pro-Resolving Lipid Mediators by Apoptotic Neutrophils]
Protocol for the isolation of the lipid-rich microdomains of the plasma membrane, notably caveolae and lipid rafts. Methods for the isolation of lipid rafts are based on the insolubility of these structures in the nonionic detergent TritonX-100. Either the intact cells are treated with a detergent-containing solution or a post-nuclear supernatant is prepared from a cell homogenate and then Triton X-100 is added to this supernatant. - [Read S20 Purification of detergent-insoluble lipid rafts from cells and tissues.]
Protocol for simple staining. Smear is stained with a solution of a single dye which stains all cells the same color. Differentiation of cell types or structures is not the objective of the simple stain. However, certain structures which are not stained by this method may be easily seen, for example, endospores and lipid inclusions. - [Read Simple Staining Protocol]
This protocol describes two transfection methods for expressing GFP-tagged actin in primary neurons. The lipid reagent DOTAP (Roche Diagnostics) method produces actin-GFP-expressing hippocampal neurons that survive well during long periods in culture. The calcium phosphate method can be used to transfect neurons that have already been growing on coverslips in vitro. Transfected cells suitable for imaging can be obtained in cultures up to 15 days in vitro. - [Read Transfecting Cultured Hippocampal Neurons with an Actin-GFP Plasmid]
Protocol describes two transfection methods for expressing GFP-tagged actin in primary neurons. The lipid reagent DOTAP (Roche Diagnostics) method produces actin-GFP-expressing hippocampal neurons that survive well during long periods in culture. - [Read Transfecting Cultured Hippocampal Neurons with an Actin-GFP Plasmid Protocol]
Accumulation of lipophilic substances, many of which may be environmental chemicals, affects the membrane lipid order and consequently affects the functions of these proteins. Since, the function of important cellular proteins, such as the H+-ATPase strongly depends upon the integrity of the lipid bilayer, the activity of the H+-ATPase may be used as a sensitive indicator of the effect that a chemical may have on the viability of the cell. - [Read Yeast Plasma Membrane H+ -ATPASE Toxicity Test]