This kit sustains FoxP3 expression in expanded Treg cells that were previously isolated with the CD4
+ CD25
+ Regulatory T Cell Isolation Kit, mouse. The Treg Expansion Kit is based on MACSiBead™ Particles pre‑loaded with CD3 and CD28 antibodies. Optimal expansion of Treg cells is accomplished by using pre-loaded MACSiBead Particles and Treg cells at a bead-to-cell ratio of 3:1 and recombinant interleukin 2 (rIL-2) at a concentration of 2,000 U/mL.