Bio-reduction of redox-sensitive albumin conjugates in FcRn-expressing cells.

Disulfide-containing IgG-, Fc-, or albumin-based prodrugs that rely on FcRn-trafficking by endothelial cells for prolonged circulation in the body might be hampered by premature bio-reduction processes during FcRn-mediated recycling events. A detailed bio-reduction analysis of redox-sensitive albumin conjugates in two FcRn-expressing cell lines has been performed. The obtained results indicate that the FcRn-mediated recycling pathway is not (or is only poorly) bio-reducing.