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SEKISUI XenoTech Introduces Lysosomal Test Systems for Biopharmaceutical Development

Lysosomes and Tritosomes Now Available as Standard Products

SEKISUI XenoTech now offers hepatic human lysosomes and rat tritosomes as standard test systems. These products contain high concentrations of lysosomal degradative enzymes and constitute advantageous test systems for analysis of catabolism and/or activation for targeted biopharmaceuticals that enter cells through the endosomal-lysosomal pathway.

“Lysosomes and tritosomes are a convenient in vitro drug development tool to cost-effectively evaluate lysosomal stability of biopharmaceuticals and macromolecules. The data provided by these systems is used to direct development of biologics, such as ADCs, siRNA/RNAi molecules, immunotherapeutics, biodegradable copolymers and nanoparticles, etc.” explained Chris Bohl, Ph.D., Global Technical Support Manager for SEKISUI XenoTech’s products.

Purified hepatic lysosomes show superior lysosomal enzymatic activity when compared to liver homogenate or S9 fraction, with low contaminating activity from mitochondrial enzymes. Rat liver tritosomes are hepatic lysosomes isolated from Tyloxapol-treated animals. The treatment allows for improved separation of the organelle from the mitochondria, and consequently, high specific activity of its catabolic enzymes.

Dr. Bohl commented, “Our rat liver tritosomes compliment human hepatic lysosomes as in vitro reagents that are more predictive than individual purified proteins, as multiple enzymes or physical characteristics synergistically affect stability of biomolecules. For instance, ADCs are likely to have a heterogeneous drug antibody ratio (DAR) and targeted modifications that stabilize the compound while in circulation. Differing amounts of drug, conjugated to various regions of the antibody, with assorted types of linkers will undoubtedly affect ADCs’ stability. Therefore, it is beneficial to conduct initial screens with this simple and in vivo-relevant system.”

SEKISUI XenoTech’s lysosomal isolation protocol has been optimized through characterization by western blotting, enzymatic activity and protease content. You can learn more by contacting SEKISUI XenoTech or visiting the company’s website, which features a lysosome characterization postertritosomes FAQwebinar on lysosomes and tritosomes for characterization of biologic drugs and more.

SEKISUI XenoTech’s human liver lysosomes and rat liver tritosomes are available through the company’s online store, and other custom preparations of lysosomes and tritosomes are made-on-demand.

About SEKISUI XenoTech

SEKISUI XenoTech, LLC is a global Contract Research Organization utilized by 98% of top pharma companies and numerous other organizations. For almost 25 years, the company has offered proven drug development expertise, providing an ever-evolving selection of cell and tissue-based productsscreeningradiolabeling, API manufacturing, in vitro ADME Tox and pharmacologyin vivo ADME Tox and QWBAmetabolite ID and productionbioanalytical services and consulting. SEKISUI XenoTech’s product selection includes a wide range of high-quality unique and standard reagents, including subcellular fractionshepatocytesmediatissue samplescell linesrecombinant enzymessubstrates & metabolites and more. The company also regularly prepares and delivers custom-designed products and services in response to client requests. For additional information, please refer to the company’s website at