Anti-Hu CD20, 2H7, PE, 25tests

This mouse monoclonal antibody, supplied by STEMCELL Technologies, targets the human CD20 antigen and is conjugated to phycoerythrin (PE) for fluorescent detection. The clone, designated 2H7, is of the IgG2b, kappa isotype and was raised against human tonsillar B cells. The reagent has been verified for flow cytometry (FC) and for cell separation (CellSep) applications, including purity assessments of cells isolated with EasySep™ kits such as the Human Whole Blood CD20 Positive Selection Kit, Human CD19 Positive Selection Kit II, and HLA Whole Blood Lymphoid Positive Selection Kit.

The antibody recognizes CD20, an approximately 35 kDa non-glycosylated type 1 transmembrane protein of the MS4A family, also known as B-lymphocyte antigen, B1, Bp35, Leu-16, or MS4A1. The 2H7 epitope has been mapped to the amino acid sequence YNCEPANPSEKNSPST, located in the large extracellular loop. CD20 is expressed on pre-B cells, resting and activated B cells, some follicular dendritic cells, and a subset of T cells, with expression lost upon differentiation into plasma cells. Through associations with the B cell receptor (CD79), MHC class I and II, CD53, CD81, and CD82, CD20 initiates intracellular signalling pathways that modulate B-cell activation, proliferation, and differentiation, and is thought to form multi-subunit ion channels that regulate calcium ion flux across the plasma membrane. The reagent cross-reacts with cells from human, rhesus, cynomolgus, baboon, chimpanzee, capuchin monkey, Nancy Ma's night monkey, pigtailed macaque, and squirrel monkey.

For flow cytometry, the suggested use is 5 μL per 1 × 10⁶ cells in 100 μL, or per 100 μL of whole blood, with titration recommended for optimal performance in each application. The antibody is purified by affinity chromatography and supplied in a phosphate-buffered formulation at pH 7.2 containing 0.09% sodium azide and 0.2% (w/v) bovine serum albumin, free of unconjugated PE and unconjugated antibody. It should be stored undiluted at 2 – 8 °C; the product should not be frozen and should be protected from prolonged exposure to light. The product is classified as a laboratory reagent and is not considered hazardous under the 2012 OSHA Hazard Communication Standard (29 CFR 1910.1200).