StemExpress, a Folsom, California based leading supplier of human biospecimens, announces the release of frozen Peripheral Blood Leukopaks. Leukopaks provide an enriched source of peripheral blood mononuclear cells (PBMCs) with low granulocyte and red blood cells that can be used in a variety of downstream cell-based applications.

StemExpress’ cell-rich Leukopaks are collected using an FDA-approved apheresis machine. Once collected, the Leukopaks are frozen using a controlled rate freezer to ensure maximum viability. A full Leukopak from a single donor contains 1x1010 total nucleated cells (TNCs) and can be divided into equal volumes before cryopreservation and shipped to multiple locations.

Frozen Leukopaks:

  • Perfect for the preservation of cell viability during global shipping
  • Provide convenience in the timing of consecutive experiments
  • Ideal for developing inter-laboratory precision of cell-based assays (i.e. ELISpot & flow cytometry)
  • Model quality control material for proficiency testing of multiple clinical laboratories

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