Lactoferrin is an iron-binding glycoprotein of the transferrin family, which is released to most biological fluids, with particularly high levels in milk. It has anti-inflammatory (e.g. sequestering of lipopolysaccharides), anti-microbial (e.g. blocking of viral attachment to the target cell), and immunomodulatory properties and can prevent infections in young children. Lactoferrin is considered to bridge the innate and adaptive immune responses. It also participates in iron homeostasis, regulation of cellular growth and differentiation and protection against cancer development and metastasis. Besides biological fluids it is also found in the secondary granules of neutrophils.