Holo-Human transferrin is an iron-loaded glycoprotein that serves as the primary iron-transporting molecule in human serum. Holo-Human transferrin binds ferric ions with high affinity and mediates their cellular uptake through transferrin receptor interactions, ensuring physiological iron homeostasis. Holo-Human transferrin is widely used in serum-free cell culture systems to provide bioavailable iron in a physiologically relevant form, supporting cellular growth and metabolism across diverse cell types.