RosetteSep Human B Enrichment, 10 mL

STEMCELL Technologies' cell separation portfolio includes a Human B Cell Enrichment Cocktail designed to enrich B cells from human whole blood by negative selection. The antibody cocktail contains monoclonal antibodies bound in bispecific Tetrameric Antibody Complexes (TACs) directed against cell surface antigens on non-B cells. These complexes crosslink unwanted cells in whole blood to multiple red blood cells, forming immunorosettes that increase the density of unwanted cells so they pellet with free RBCs during density gradient centrifugation. The desired B cells remain unlabeled and are collected as an enriched population at the interface between plasma and density gradient medium.

The product is used at 50 μL/mL of whole blood, incubated for 20 minutes at room temperature (15 - 25°C), then diluted with an equal volume of PBS + 2% FBS and layered over a density gradient medium such as Lymphoprep™, RosetteSep™ DM-L, or Ficoll-Paque™ PLUS. Samples are centrifuged for 20 minutes at 1200 x g with the brake off. After enrichment, residual RBCs can be removed using Ammonium Chloride Solution.

In a typical enrichment profile starting with fresh whole blood at 6% CD19+ cells, the enriched fraction reaches 81% CD19+ cells with 53% recovery of CD19+ cells. Mean results (n = 31) show purity of 83 ± 8% CD19+ cells and recovery of 71 ± 39% CD19+ cells. The CD19+ cell content of the enriched fraction typically ranges from 81% - 83%. Purity can be assessed by flow cytometry using anti-CD19 (Clone HIB19) or anti-CD20 (Clone 2H7) antibodies. The cocktail can also be used with buffy coat or leukapheresis samples, where nucleated cells should not exceed 5 x 10^7 cells/mL and RBCs should be present at a ratio of at least 100 RBCs per nucleated cell. The product is part of STEMCELL Technologies' cell separation solutions suitable for HLA testing workflows, including flow cytometric crossmatch (FCXM) assays. It should be stored at 2 - 8°C until the expiry date, not frozen, and may be shipped at room temperature (15 - 25°C). STEMCELL Technologies' quality management system is certified to ISO 13485 medical device standards. The product is for research use only; not intended for human or animal diagnostic or therapeutic uses.