Transferrin-like molecule

In the context of dmg delivery, certain cell surface receptor and ion-channel families are particularly appealing as dmg delivery targets. Well-characterized examples include the lectin-like receptor gene family as receptors for glycosylated molecules, as well as vitamin- and trace element-uptake systems such as the transferrin-receptor. 

Many have reported the special properties of endothelial cells in brain vasculature. Small hydrophobic molecules diffuse across the BBB large and/or hydrophilic molecules may be transported only if a specific receptor or transporter exists. Thus, small hydrophobic molecules penetrate the brain by diffusion nutrients such as glucose and certain amino acids are transported into the brain by specific transporters and several large proteins like transferrin are transcytosed into the brain via specific receptors. 

UV-difference spectroscopy, and other studies in vitro with plutonium (IV), tho-rium(IV) and a number of trivalent lanthanides, have demonstrated that, like iron, two lanthanide or actinide metal atoms are bound per transferrin molecule (Duffield and Taylor 1986, Taylor et al. 1991, Zak and Aisen 1988). Saturation of the lanthanide- or actinide-containing transferrin with excess iron results in a liberation of the f element, thus suggesting that these metals are binding to the two iron-binding sites on the transferrin molecule (Taylor et al. 1991). These studies have also shown that bicarbonate is necessary, as a synergistic anion, for the binding of actinides and lanthanides to transferrin. 

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