Expertise-driven, High-yield Cell Collections for Leukopaks

• Overview of cell counts from leukapheresis collections
• Versiti leukopak: flow cytometry example

Leukopaks are a rich source of white blood cells that provide a higher mononuclear cell count (MNC) andhigher purity than white cells collected from whole blood donations. Leukopaks are the starting material ofchoice for cell therapy applications and manufacturing.

Leukopak products are collected via a leukapheresis procedure, the process of extracting white blood cellsfrom the peripheral blood using an apheresis machine. The remaining blood components are returned tothe donor.

Leukopaks can be fresh or cryopreserved, sourced from healthy donors or those with specific diseasestates. Products may be either non-mobilized or mobilized (stimulated mobilization of CD34+ cells).Leukopaks can be used in research, cell-based assays, cell therapy process development, and drugdevelopment and manufacturing. Versiti provides two tiers of leukopak products: research-use only(RUO), useful in discovery and pre-clinical phases; and clinical grade (FDA 21 CFR 1271 compliant), tosupport manufacturing in clinical phase trials and commercialization.

Leukopak products vary in cell counts due to several reasons, including execution of the leukapheresiscollection process and system utilized, donor characteristics, and whether the donor was able to providethe required blood volume to process the total number of cells required by the research protocol.

The leukopak collection process uses one single donor per leukopak product collected. The volume ofwhite blood cells in a single leukopak allows the researcher to perform necessary assays, validation andquality assurance.

As with any human-derived starting material, innate variability exists in leukapheresis collections donorto-donor, and even collection-to-collection from the same donor. Each donor’s cell characteristics andquantification may impact the types of cells collected during leukapheresis. To maximize cell quality orquantity, a commitment to staff education and robust training on leukapheresis procedures and donormanagement is essential.

Dedicated resources and training provided to staff on leukapheresis protocols and cell therapycollections increases collection efficiency to meet cell yield requirements for the researcher, as well asprovides for a positive donor experience. Protocols should be developed to assist with streamlining thecollection process for both the researcher and donor.

A comprehensive donor management strategy is needed to support a research project or study.Identifying, recruiting, screening and managing donors is integral to collecting leukopak products.Managing the health of a donor is important to prevent fatigue and reduced cell counts. To mitigatedonor challenges and help ensure consistency in production, having committed, recallable donorsassigned to a specific project ensures a consistent yield of cells to keep the progress running smoothlythroughout the duration of research. Adhering to stringent donor criteria, operating under an IRBapprovedprotocol ensures a safe leukapheresis procedure for the donor.

Versiti leukopak products are collected following formal quality systems that result in reduced variabilityand risk to help ensure your projects progress smoothly throughout the duration of your research.

The expected total nucleated cell count (TNC) of a whole Versiti leukopak product is 10-12 billioncells. The leukopaks contain high concentrations of monocytes and lymphocytes, as well as lowconcentrations of neutrophils. Leukopaks are collected at Versiti’s FDA-registered collection center fromIRB-consented, healthy human donors by leukapheresis using the Spectra Optia Apheresis Systemunder approved SOPs in accordance with all applicable federal and state regulations.

Every clinical-grade product release is subject to review by an independent quality assurancerepresentative and approval of the batch record. A certificate of analysis (COA) is provided with eachproduct.

The data and charts below represent a sample breakdown of expected cell type and mix counts of aVersiti leukopak product using flow cytometry. Product flow cytometry results are investigational-useonly and are not to be used for diagnostic or clinical purposes.

This product was collected under an IRB-approved protocol, as per 45 CFR 46 and 21 CFR 50 and 56, foruse in research and further manufacturing. Testing of the product was in accordance with 42 CFR 493.

The data and charts below represent a sample breakdown of expected cell type and mix counts of aVersiti leukopak product using flow cytometry. Product flow cytometry results are investigational-useonly and are not to be used for diagnostic or clinical purposes.

This product was collected under an IRB-approved protocol, as per 45 CFR 46 and 21 CFR 50 and 56, foruse in research and further manufacturing. Testing of the product was in accordance with 42 CFR 493.