An Immunologic Study of The Iron-Binding Protein

Antisera prepared against two samples of crystalline iron-binding protein were examined as regards homogeneity by means of supernate analyses for simultaneous presence of antigen and antibody, by means of the Oudin diffusion method, and by their characteristics as determined with the quantitative precipitin technique. Antisera thought to be homogeneous on the basis of these criteria were used for estimation of iron-binding protein in whole human serum. Certain antisera gave values for iron-binding protein that were in good agreement with chemical estimations of this protein. Other antisera, however, gave immunologic values which were in excess of chemical values. Only by direct comparison of immunological values with chemical values was it possible to select suitable antisera for the immunologic estimation of iron-binding protein.