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Human Liver Microsomes, Human Liver Cell Fractions, Cytosol & More

Subcellular fractions are widely used in drug discovery & preclinical development to evaluate in vitro metabolism of drug candidates. Common assays using Human liver microsomes and other subcellular fractions as a recommended test system, include metabolite identification (MetID), enzyme inhibition, reaction phenotyping, and other in vitro drug metabolism and pharmacokinetics (DMPK) studies. Our wide selection of preparations features matching S9, cytosol, and microsome preparations from the same donor pool and extensive characterization through validated LC-MS/MS methods.

Microsomes contain the highest concentration of many important drug-metabolizing enzymes including cytochrome P450 (CYP) and UDP-glucuronosyltransferase (UGT) enzymes. S9 fractions contain a mixture of cytosolic and microsomal enzymes, which express a wide variety of phase I and phase II enzymes and are recommended for many different ADME and pharmacokinetic (pk) studies. Cytosolic fractions contain many unique drug-metabolizing enzymes that are not enriched in microsomes and are a recommended test system for evaluating soluble phase II metabolic reactions of a test compound – especially once reactions have been observed in S9 fractions, as the microsomal enzymes have been significantly reduced from the cytosol fraction allowing for improved evaluation of non-CYP metabolism.

If you require microsomes, S9, cytosol, homogenate, lysosomes or mitochondria not available through our standard product offerings, custom subcellular fractions can be easily ordered to meet the specific needs of any study. See all of our Custom Test Systems capabilities or get in touch with a specialist to find out how we can help.

Human hepatic subcellular fractions can be used to explore durg-metabolizing enzyme activity in the liver

Standard Human Liver Cell Fractions

Human liver microsomes contain a wide variety of drug-metabolizing enzymes and are commonly used to support in vitro metabolism studies, such as reaction phenotyping, metabolic stability, metabolite identification (MetID), and enzyme inhibition. We offer pooled microsomes produced from a large number of North American donors with very diverse demographics. This allows us to offer subcellular pools that exhibit enzymatic activities that are representative of the general North American population. We also prepare subcellular fractions from individual donors that have been genotyped for single nucleotide polymorphisms (SNPs) that have been demonstrated to alter specific enzymatic activity.

Pooled human liver S9 contains both microsomal and cytosolic fractions that account for more drug-metabolizing enzymes than are in microsomes alone and can give a more complete picture of drug metabolism. Options are available of variable pool size and enzymatic activity characterization, including aldehyde oxidase (AO) and xanthine oxidase (XO).

Cytosol, homogenate, and mitochondria preparations from human liver tissue are used in drug development as predictive test systems to evaluate specific drug-metabolizing enzymes that are highly expressed in certain cellular compartments/organelles. Pools of each fraction are available from one or mixed genders of various pool sizes to best predict metabolic activity in patient populations.

Human liver lysosomes are cellular organelles isolated from human liver tissue and are a primary site of degradation within the cell. This test system can be used in drug development to evaluate lysosomal stability of large molecule biopharmaceuticals and macromolecules. Purified fractions show superior lysosomal enzymatic activity compared to microsomes and S9 with low contaminating activity from mitochondrial enzymes.

Isolation of subcellular fractions: Tissue > Homogenate > S9 > Cytosol > Microsomes

Custom Human Subcellular Fractions

If you require microsomes, S9, cytosol, homogenate, lysosomes or mitochondria not available through our standard product offerings, custom subcellular fractions can be easily ordered to meet the specific needs of any study. Our highly experienced team can design and create custom pools and can characterize the custom product with over 40 different characterization assays available. See all of our Custom Test Systems or get in touch with a specialist to find out how we can help.

More Information About Subcellular Preparations

Learn more about our capabilities, characterization of subcellular fractions, safety, handling and storage, and more

Centrifuged subcellular fractions for in vitro testing