This purified polyclonal antibody reacts with human fetuin by ELISA and western blot. Although not tested, this antibody is likely functional in immunohistochemistry and immunoprecipitation. A doublet band or slightly lower molecular weight band (see Figure 1, lane 1) may be visible by western blot due to proteolytic processing, variable glycosylation and/or phosphorylation. Proteolytic processing may include the removal of a 40 amino acid residue bridging peptide from the A and B chains of fetuin in vivo.