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XenoTech Awarded Cryopreservation Patent, Achieves Numerous Hepatocyte Enhancements

Today, XenoTech was issued U.S. Patent No. 9,642,355 for the “cryopreservation of cells and subcellular fractions,” specifically related to XenoTech’s CryostaX® test systems, which are the only single-freeze pooled hepatocyte products in the industry. The company has also enhanced its full catalog of hepatocyte offerings with increased cell yield, viability and more.

Hepatocytes are liver cells that are commonly used in drug discovery and preclinical drug development experiments because intact hepatocytes contain the major hepatic drug-metabolizing enzymes necessary for preclinical studies. This makes them ideal in vitro test systems for studies of metabolic stability, hepatic uptake and transporters, CYP induction screening, hepatotoxicity, etc. Zell Woodworth, Products Division Director for XenoTech explained, “Our hepatocyte expertise stems from decades of preparing these test systems for our own contract research. Utilizing the hepatocytes that we produce in our own contract studies allows an added level to quality control beyond the standard characterization that most hepatocytes vendors provide.”

XenoTech’s now patented single-freeze preparation process minimizes cryoinjury, promoting high viability, cell yield and enzymatic activity for long-term consistent test results. In addition to the benefits of an initial single-freeze preparation, the resulting unique, solid state “pellets” do not require the usual, extra thawing step for laboratory use, and allow the hepatocytes to be pooled without thawing and re-freezing. The CryostaX® hepatocyte pellets can be selected individually or combined from over 200 donors based on the required specific enzyme activities; assured minimum yield; pool size; donor BMI, disease state, age, ethnicity, gender or alcohol, tobacco and drug use, serology, etc. Lots are available for suspension or plating.

The patented CryostaX® cryopreservation method was invented by Maciej Czerwinski, Ph.D., Director of Consulting for XenoTech. Dr. Czerwinski commented, “CryostaX® human hepatocytes are a highly convenient and cost effective test system. Their unique nature allows them to be quickly and easily custom-prepared according to researchers’ needs, at no additional cost, which is why we are looking into preparing more of our test systems with this method.”

XenoTech additionally implemented several other improvements over the last year, from technology to methodology, resulting in 20-40% higher cell yield and almost 10% higher viability. Furthermore, the company renegotiated its donated liver contract for access to 3.5 times more livers, allowing the selection of higher quality tissue and specific demographics. XenoTech also began providing certificates of quality and sterility for its hepatocyte media. Woodworth added, “These enhancements were all part of the company’s ongoing efforts to maximize its hepatocyte offerings, performance and characterization data.”

XenoTech’s CryostaX® and other hepatocytes are available in large lots with extensive characterization and no minimum order quantity requirements. Cells from a variety of species are available, including human, rodent, monkey, canine, minipig and rabbit, with other species available as custom preparations.

Patent CryostaX

About XenoTech

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. 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