Apheresis-derived Leukocytes

Key Biologics offers two unique products containing leukocytes collected by apheresis. For more information, click the product name.

• Source Leukocytes (Buffy Coats)

• Leukocyte Reduction Filter Product

Source Leukocytes [a Key Biologics exclusive product]

Key Biologics is the exclusive provider of apheresis-derived source leukocytes collected on the Haemonetics PCS^®2 collection system. These products are also known as apheresis buffy coats.

Collection of a Source Leukocyte by apheresis produces a product that contains 50% to 100% more nucleated cells than would be found in a whole blood-derived Source Leukocyte. In addition, subjects may provide this product once a week, up to 24 times per year due to the small amount of red blood cell loss associated with collection of this product. Conversely, subjects who provide whole blood for production of Source Leukocytes may donate only six times per year and only once every eight weeks.

Apheresis-derived Source Leukocytes are collected from subjects qualified in accordance with current regulations and requirements for donors of transfusible blood components, including screening with the Uniform Donor History Questionnaire developed by the AABB and accepted by the Food and Drug Administration for screening of donors of transfusible blood components.

Selection criteria may be adjusted at the request of the customer depending on the intended use of the product and the customer’s requirements, provided that subject safety requirements are met. At the customer’s request, subjects with a history of travel or medication ingestion that would preclude them from providing a blood product suitable for transfusion may provide Source Leukocytes for non-clinical and non-injectable uses.

We also offer qualification samples on potential subjects to allow the end-user to determine suitability for targeted use. Specific subjects may be requested for product collection.

Subjects are prescreened for evidence of transmissible infectious diseases with the standard panel of tests used to screen blood products for transfusion acceptability. This panel of tests, with the exception of screening for exposure to T. cruzi, is usually repeated with each product collection.

Specific subjects may be selected from our database based on:

• Blood type
• Gender
• Ethnicity
• Human Neutrophil Antigen genotype
• Human Leukocyte Antigen phenotype

Optional pre-collection qualification screening is available:

• Total white cell count, neutrophil count, and/or other cell counts
• Recent medication usage

Optional post-collection release screening is available:

• Total nucleated cell and/or other cell fraction yield

Packaging and Shipment

In alignment with the intended use of the product and the customer’s requirements, Source Leukocytes are generally packaged and shipped on the date of collection for overnight delivery.

Products are packaged in a manner that ensures maintenance of a temperature between 1°C and 10°C or between 20°C and 24°C during shipment at the customer’s discretion.

Continuous temperature monitoring data tracking devices are available for use at the customer’s request.

Leukocyte Reduction Filter Product (COBE^® TrimaTM LRS chamber)

Plateletpheresis products collected using a COBE^® TrimaTM collection device and Trima Accel® software contain very few residual leukocytes due to the use of leukocyte reduction technology. During the collection process, leukocytes are trapped within an integrated chamber (LRS chamber). Following collection of the platelet product, some of the leukocytes are returned to the donor; however, approximately 1.5x10⁹ leukocytes remain in the chamber. Mononuclear cells comprise the majority of cells in the chamber.

Key Biologics aseptically salvages the LRS chambers following plateletpheresis procedure by doubly heat-sealing the chamber’s ingress and egress tubing and separating the chamber from the tubing. A unique tracking number is adhered to the chamber to allow linkage to the collection procedure, as needed. The chambers with a small amount of connected tubing are provided en bloc to researchers.

If the customer wishes, Key Biologics will collect the residual leukocytes into a transfer bag by flushing the chamber contents with PBSS. The collected cell fraction is also labeled with a unique tracking number and provided to researchers.

The chambers and the collected cell fractions are stored at room temperature pending shipment. In alignment with the intended use of the product and the customer’s requirements, chambers or collected cells can be packaged and shipped on the date of collection for overnight delivery.

Products are packaged in a manner that ensures maintenance of a temperature between 20°C and 24°C during shipment, unless the customer specifies an alternative method.

Continuous temperature monitoring data tracking devices are available for use at the customer’s request.