A leukopak is a sterile bag of apheresis product enriched with white blood cells. This high concentration is a result of leukapheresis—the process of extracting leukocytes from a blood donor while returning other blood components to the donor.
Depending on the volume of blood processed, a leukopak can contain up to 20 billion cells—roughly half of which are T cells. The remaining half is composed of monocytes, B cells, NK cells, granulocytes, and red blood cells. A leukopak’s high concentration of valuable blood cells makes it an integral tool in immune studies and cell therapy. For researchers in need of a large number of white blood cells from a single donor, leukopaks are preferable.
One of the main applications of leukopaks is within cell therapy research. Many cell therapy studies require the sample to come from a single donor. Due to the robust and concentrated nature of leukopaks, up to 20 times more volume of viable cells from a single donor is available for study.
There are different types of leukopaks available on the market. Which of these is best for the experiments at hand will depend on the nature and timing of the cell study. Leukopak viability is important to maintain throughout the collection and shipping process, so selecting the right leukopak is imperative to the success of the experiment.
Fresh leukopaks are shipped at 2-8 degrees Celsius and are recommended to be used immediately after receiving the shipment. For same-day experimentation, this option could be convenient and reliable. However, viability drops quickly among fresh leukopak cells and a missed shipment could mean the complete loss of a viable product.
A cryopreserved leukopak, much like the name suggests, is a leukopak that’s been frozen to preserve the blood cells. Cryopreserved leukopaks contain the same contents as a fresh leukopak but allow for much more lenient timing and use with minimal or negligible cell viability loss. Similar to fresh leukopaks, cryopreserved leukopaks vary in contents depending on the supplier, the success and type of apheresis, and the donor quality.
Experiments can be restricted by their shipment times if the lab waits for fresh leukopak deliveries daily. Cryopreserved leukopaks eliminate the stress of delayed shipments and transit by prolonging shipping and storage durability from 48 hours as a fresh leukopak to 10 days hyper-frozen.
Cryopreserved leukopaks can also be stored for long periods and thawed in a water bath when needed. In an -80 degrees Celsius freezer, a cryopreserved leukopak can last up to a month and even longer when stored in iquid nitrogen.
A mobilized leukopak is a highly enriched leukopak extracted from donors treated with mobilization factors—external activators intended to boost the release of progenitor cells from bone marrow.
Mobilized leukopaks are created through mobilized apheresis—where a consenting donor takes a regiment of drugs to increase the release of CD34+ cells into the bloodstream. This process results in a leukopak with higher stem cell concentrations and has specific applications in regenerative medicine, transplant therapy, and cell therapy.
Leukopaks can vary in content by preparation type, supplier, apheresis process and success, intended use, and donor quality. Generally, leukopaks consist of 50% T cells, 20% monocytes, 10% B cells, 10% natural killer (NK) cells, 3% granulocytes, and 3% hematocrit (red blood cell volume). Mobilized leukopaks can contain even higher concentrations of some of these elements.
The white blood cell count of a leukopak is over six times greater than in the same volume of whole blood, and 20 times greater in the concentration of human PBMCs. All of these components can be separated from leukopaks for research and are often divided based on the experiment at hand. Learn how to use Akadeum’s Microbubble Leukopak Human T Cell Isolation Kits for seamless T cell separation in 60 minutes.
Leukopaks and mobilized leukopaks are extracted via apheresis—the removal of whole blood from the body, separating it into various cell subtypes, and returning the plasma to the initial donor in one process. Apheresis can be used to collect a concentrated solution of blood components but can also be utilized to separate part of the blood that can contain disease-provoking elements from an at-risk patient.
In the case of leukopak production, whole blood is extracted and put through an apheresis machine that separates the white blood cells and returns the remaining blood components to the donor.
Similar to apheresis, mobilized apheresis involves extracting, separating, and returning blood components to a single donor. However, mobilized apheresis specifically utilizes an approved donor who has been placed on a regiment of stem-cell release-boosting drugs to enrich the CD34+ concentration of the resulting leukopak.
The cost of a leukopak can depend on the volume and percentage of blood cells needed. Typically, leukopaks are sold in full, half, or quarter bag quantities or cell count estimates.
For example, a full leukopak bag can consist of up to twenty billion total cells depending on the supplier and can cost around $4,000. If less volume of cells is required, quarter and half bags are available for $2,000-$3,000.
Leukopaks serve as a source of otherwise difficult-to-access and highly desirable blood cells. Utilized across multiple biomedical applications, leukopaks are unique in their concentrated and single-donor attributes.
Some leukopaks are modified to have specific ratios of blood components to aid in understanding particular conditions. Additionally, leukopaks assist in the study of blood and autoimmune diseases, such as HIV and AIDS, and provide a reliable source of cells to accurately test the immune system.
GMP is an abbreviation for Good Manufacturing Practices. Leukopak suppliers are regulated by GMP compliance checks, including quality assurance audits and rigorous donor selection processes. Suppliers must follow standard tissue and collection procedures as well as provide nationally approved SOPs. In addition to keeping a well-documented account of leukopak manufacturing and collection, leukopak suppliers must also perform equipment standardizations.
Leukopaks can replace buffy coat procedures, especially in cases where high white blood cell concentrations are needed. Leukapheresis results in a higher purity and PBMC concentration per volume processed than that of a buffy coat—as much as 20x as concentrated.
Because of this high concentration, more experiments can be performed on one leukopak as opposed to performing multiple buffy coat extractions. Additionally, GMP-compliant leukopaks are available to ensure a reliable product and controlled clinical trials.
Leukopak suppliers can modify the percentage of each cell type within a leukopak, tailoring the concentration of blood cells to the exact needs of the researcher or experimental protocol. By processing larger quantities of blood, the resulting leukopak solution is much richer. Mobilized leukopaks also utilize a drug regimen to spike the donor blood with the desired cell types.
By reimagining the possibilities of cell separation technologies, Akadeum’s microbubble applications bring ease and innovation to otherwise grueling processes. Our 60-minute protocol replaces a lengthy and error-prone preparation step with a hardy and high-yield system that provides reliable delivery every time.