Anti-Ms CD25, PC61.5, AZ, 100µg

This rat monoclonal antibody, supplied by STEMCELL Technologies, targets mouse CD25 (the low-affinity interleukin-2 receptor α chain), a ~55 kDa type I transmembrane glycoprotein expressed on T and B cell progenitors, activated (but not resting) T and B cells, regulatory T cells, dendritic cells, and activated monocytes and macrophages. The antibody, clone PC61.5 (IgG1, lambda), is APC-conjugated and was raised against the IL-2-dependent cytolytic mouse T-cell clone B6.1. CD25, together with CD4 and FOXP3, is regarded as a phenotypic signature for Treg cells; CD25 associates with CD122 (IL-2Rβ) and CD132 (IL-2Rγ) to form the high-affinity IL-2 receptor complex. Binding of clone PC61.5 has been reported to inhibit IL-2 binding to the low- and high-affinity receptors, and the PC61.5 epitope is distinct from the IL-2 binding site and from the epitopes recognised by clones 7D4 and 3C7.

The antibody is verified for flow cytometry and has been used to confirm purity of cells isolated with STEMCELL's EasySep kits, including the EasySep Mouse T Cell Isolation Kit. It is formulated in a phosphate-buffered solution at pH 7.2 containing 0.09% sodium azide and 0.1% gelatin, and is purified by affinity chromatography before conjugation with APC; the supplied solution is free of unconjugated APC. For flow cytometry, the manufacturer's suggested use is ≤ 0.125 μg per 1 × 10^6 cells in 100 μL, though titration is recommended for each application. The product is stable at 2–8 °C when stored undiluted; it should not be frozen and should be protected from prolonged exposure to light.

According to the manufacturer's safety data sheet, the reagent is a clear liquid intended for use as a laboratory reagent and is not classified as hazardous under the 2012 OSHA Hazard Communication Standard (29 CFR 1910.1200).