Peripheral Blood Leukopaks
Your source for quality fresh and cryopreserved human cells
StemExpress' Peripheral Blood Leukopaks provide enriched peripheral blood mononuclear cells (PBMCs) with low granulocyte and red blood cells. This highly enriched PBMC fraction requires minimal downstream processing (i.e. Ficoll) and can be used directly for isolating high yields of immune cells, such as CD4+ T cells, CD8+ T cells, CD19+ B cells, monocytes, and other immune cells. High cell yields allow researchers greater reproducibility of experiments from a single donor (minimizing donor-to-donor variation), a decrease in same cell variability, and scalability of experiments. In addition, up to 12 Leukopaks can be collected from the same donor in a given year, providing an ample amount of PBMCs for large-scale experiments and research studies.
Popular Peripheral Blood Leukopak Products
Your Cells, Your Way!
HIGH-QUALITY LEUKOPAKS
Learn more about our Frozen Leukopak!
Cell-rich Leukopaks are extracted using an FDA-approved apheresis machine. Once collected, fresh Leukopaks are sent out on the same day or frozen immediately to ensure a highly viable product.
- 1x1010 TNCs/full bag
- Highly-enriched PBMCs
- ≥95% viability (fresh)
- HBV, HCV, HIV negative
- IRB approved

DONOR SELECTION
We provide customizable options to ensure you receive the Leukopak you need when you need it.
- Fresh or Frozen
- Extensive donor pool
- Recallable and repeat donors
- Specific donor demographics (age, weight, ethnicity, etc.)
- Donor lifestyle characteristics (BMI, smoker/non-smoker, etc.)
- Medical history (allergies, medications, etc.)
- HLA, RhD, and ABO typing available
- Additional infectious disease screening (CMV, etc.)
- Much more....
For orders of Fresh Leukopaks with no donor requirements, you can receive your Leukopak in as little as 3-days from the time you submit your purchase order.
CELL COLLECTION/PROCESSING
- Special processing procedures available
FLEXIBLE SHIPPING OPTIONS
- Custom media/buffer
- Customizable packaging options
- FedEx®, World Courier®, UPS®
- Same day delivery in select cities
Frequently Asked Questions
Yes, a donor is eligible to donate white blood cells every 4 weeks.
Usually around 8x109 PBMCs from a Fresh Leukopak. However, this will be dependent on how you process the Leukopak (Ficoll, RBC lysis, etc.), all of which can decrease the amount of PBMCs.
Yes, certain locations can receive same day courier delivery on Fresh Leukopaks. We can also provide same day air shipments.
No, we offer a high-quality Leukopak with minimal granulocytes and red blood cells. However, we do recommend an RBC lysis before isolating primary cells.
Cells are very sensitive to many aspects of the thawing procedure, such as heat, DMSO, agitation, and high centripetal forces. Obtaining high cell viability and recovery after thawing a Frozen Leukopak can be difficult if not performed quickly and with good laboratory techniques. At StemExpress, our laboratory technicians have years of experience handling and thawing frozen human cells and have designed a procedure that will help you obtain the highest viability and recovery of your cells. Click Leukopak Thawing Protocol to access the protocol.