IN VITRO TOXICOLOGY

Apoptosis Cell Growth Cytotoxicity Assay

IN VITRO TOXICOLOGY OVERVIEW

Marin Biologic performs a variety of in vitro toxicity tests and assays. We offer a number of assays performed under strict GLP and GMP compliance with FDA and EPA guidelines. Performing in vitro cytotoxicity assays prior to animal testing may be a cheaper alternative for initial drug screens. Since many of the assays require cell-based assays, our experience in cell biology, enables us to analyze cells morphologically as well as using molecular and biochemical techniques.

APOPTOSIS

You may want to know whether your drug candidates demonstrate cytotoxicity through apoptosis or necrosis. We will measure different parameters for apoptosis compared to necrosis. Apoptosis is characterized by early events such as expression of phosphotidylserine on the cell surface and fragmentation of the DNA, followed by loss of membrane integrity and mitochondrial function. We will discuss with you parameters such as drug concentration, time of exposure, measurement of DNA fragmentation in order to customize your in vitro cytotoxicity assay. Necrosis occurs through the action of toxic factors that act within the cell, such as irreversible inhibitors of protein, RNA or DNA synthesis, or mitotic poisons. We would measure protein or nucleic acid synthesis rates to determine your drug toxicity.

CELL GROWTH

Another measure of cytotoxicity is the inhibition of cell growth or proliferation. No one mechanism may be responsible for this observation, however, proliferation rates can be measured as a response to drug concentration. Some drugs may have a threshold level rather than a linear response for inhibition of cell growth. We will discuss parameters such as optimal target cell line, drug concentration, drug exposure time and drug delivery to customize your in vitro cytotoxicity assay.

A partial list of assays is listed below.

Cellular Mitogenesis, Proliferation Rates (see Cell Biology) Inhibition of Growth (FDA Guidelines) Adherence Morphology Apoptosis Protein Synthesis DNA, RNA Synthesis   Gene Mutation and Cell Transformation Bacterial Assays (see Molecular Biology) Mammalian Cell Assays (see Cell Biology)   Viral Removal Plaque Titering Assay

Toxicity Cr51 Release Protein Metabolism DNA Synthesis RNA Synthesis Dose Range-Finding Investigation Hemolysis     in vitro Cytogenetics Cell Cycle Kinetics   Other Methods Cytokine Release (see Cell Biology) Bacterial Endotoxin (LAL) (see Biochemistry) Determine Toxicity Mechanisms Elucidate Potential Cytotoxicities in Target Tissues Drug Screening to Prevent Cytotoxicity Cytochrome P450 Induction Studies