Structurally modified immunoglobulin

Thiophilic adsorption chromatography has been described for the purification of murine monoclonal antibodies from hybridoma cell culture containing fetal bovine serum.154 Due to the very low concentration of immunoglobulins in cell culture supernatants, binding capacity remains modest in spite of the presence of 0.5 to 1 M potassium sulfate. Further developments of this technology described by Nopper et al.155 indicated that thiophilic sorbents could be modified in their structure to increase the specificity and the binding capacity. 

Examples of the use of IR spectroscopy to detect small changes in secondary structure or changes in primary structure are given for radical-modified caeruloplasmin and immunoglobulin G. As will be demonstrated, in some instances small significant changes in the secondary structure can be detected, in other instances the data do not indicate secondary structural modifications. Thus, a key break in the... 

Fig. 7.17. Structure of the Vl and Cl domains of IgG. Layers of antiparallel 3-sheets are stacked in these domains, which have been referred to as collapsed -barrels. The antigen binds between the Vh and Vl immunoglobulin folds, and NOT in the barrel. The Cl domain is also called the immunoglobulin fold. (Top modified from Richardson JS. Adv Protein Chem. The anatomy and taxonomy of protein structure 1981 34 167 bottom reprinted in part with permission from Edmundson AB, et al. Biochemistry 1975 14 3954. 1975 American Chemical Society.)...

Fig. 2. Chemical structures of opiates. The antigenic determinant for immunoglobulin E antibodies is the N-methyl-cyclohexenyl ring in combination with a hydroxyl group on (modified from Bircher 1996)...

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