Alexa Fluor^® 488 Mouse Anti-Rat CD25 Antibody (OX-39)

CD25, also known as the interleukin-2 receptor alpha chain (IL-2Rα), is a 55 kDa type I transmembrane glycoprotein essential for immune regulation, forming part of the high-affinity IL-2 receptor complex (with IL-2Rβ and the common γ chain) that mediates IL-2 signaling in activated T cells, B cells, NK cells, and particularly in CD4+ regulatory T cells (Tregs), where its expression is critical for maintaining immune homeostasis and self-tolerance, and is dynamically upregulated upon T cell activation through transcriptional control involving NF-AT factors, while also existing in a soluble form (sCD25) that can modulate IL-2 availability and serve as a clinical biomarker in autoimmune diseases, infections, and cancers.