2. Lactoferrin
Lactoferrin (Lf) is a highly conserved pleiotropic iron-binding
glycoprotein of the transferrin family that is expressed and secreted by
glandular cells and found in most body fluids (Levay & Viljoen, 1995).
It appears in especially high concentrations in mammalian milk and was
first identified in bovine milk (Soerensen, M, 1939) and subsequently
isolated from human milk (Johanson et al., 1960). It has been found to
be a 80-kDa glycoprotein containing 703 amino acid residues, and its
primary structure has been well characterized (Jolles et al., 1984).
Since its discovery, Lf and its related peptides are mainly considered
to be important non-specific host defense molecules against a variety of
pathogens including a spectrum of viruses (Bruni et al., 2016). More
recently, Lf’s anti-inflammatory and immunomodulatory role has captured
increasing scientific interest, since it appears to be able to moderate
host response to infections and has the dual ability to stimulate the
immune system to counteract pathogenic invasion while simultaneously
preventing harmful host immune and inflammatory responses.