A bioassay measures a biological response of a cell or organ to a drug, agonist or antagonist. The types of responses include growth/inhibition/death/apoptosis, induction of gene expression (measured by qPCR)/protein production (ELISA,Western, flow cytometry)/morphological changes, etc.

A bioassay measures a biological response of a cell or organ to a drug, agonist or antagonist. The types of responses include growth/inhibition/death/apoptosis, induction of gene expression (measured by qPCR)/protein production (ELISA,Western, flow cytometry)/morphological changes, etc.

Cells can be fractionated when purification of a specific subcellular component, or the activity of the component, or investigation of drug localization is required. Cell fractions include plasma membrane, nuclei, mitochondria, cytoplasm, nucleoplasm, microsomes. Purity of each fraction is assessed with enzymatic markers.

Drugs may be presented to biological systems by themselves, as prodrugs that have to be metabolized to a form more readily taken up or in liposomes that facilitate transport across lipid membranes. Drugs may also be formulated in degradable polymers or other slow-release systems or attached to carriers to facilitate transport such as nanoparticles, to….

Drug action can be followed in a bioassay in which a cell has to respond to a signal (as contrasted to simply binding to a cell receptor). Bioassays may be developed to detect the drug being transported into intracellular compartments or may measure intracellular signaling events such as receptor phosphorylation, calcium flux, or gene activation….

The presence and the cellular localization of macromolecules can be determined by immunocytochemistry, in which cells are fixed on a microscope slide, and a molecule is stained by a specific labeling reagent and detected by fluorescence microscopy. Molecules external to the cell membrane are visualized directly whereas internal molecules require permeabilized membranes.

A drug may elicit an immune response in recipients. The ELISA is the typical method for detecting antibodies that bind to a drug. The Neutralizing Antibody Assay (NAb) measures whether the antibody blocks the activity of the drug. The assay usually is a bioassay in which the drug induces a biological response in a cell….

Gene activation or gene expression can be conveniently monitored by a DNA construct that links the regulatory components of the gene to a reporter gene, such as for a fluorescent protein or beta galactosidase. Cells can be transfected with reporter genes that are activated when certain pathways are triggered. Pathway induction is quantitated by the….

Signal transduction is the process by which a chemical or physical signal is transmitted through a cell as a series of molecular events, most commonly protein phosphorylation which results in a cellular response. Protein receptors detect stimuli from ligand agonists which trigger the process. At the molecular level, such responses include changes in the transcription….

Each cell line must be matched to a particular growth medium. As a generalization, ectodermal cells such as in the fibroblast lineage are adherent and prefer one subset of media, while blood cell types are nonadherent and prefer different formulations. Formulations usually include glucose as an energy source, vitamins, amino acids and 5 – 20%….