Alexa Fluor® 488 Mouse Anti-Human CD71 Antibody (OKT-9)

CD71, also termed transferrin receptor-1 (TFRC), is a 95-kDa type-II transmembrane glycoprotein that forms a disulfide-linked homodimer and serves as the master mediator of cellular iron uptake by binding two molecules of iron-loaded transferrin, triggering clathrin-dependent endocytosis whose efficiency is heightened in the low-pH endosome where iron is released, after which the receptor–ligand complex is recycled back to the surface; the protein is almost ubiquitously expressed but most abundant on rapidly dividing, erythroid, placental, neuronal and malignant cells whose proliferative and metabolic demand for iron keeps CD71 transcriptionally and post-transcriptionally up-regulated, while its apical domain additionally binds ferritin, selected viruses and therapeutic nanocarriers, making CD71 a key determinant of erythropoiesis, a biomarker of iron status and tumor burden, and a validated gateway for drug delivery and viral entry.