Immunoglobulin Heterogeneity Studied by Isoelectric Focusing in Polyacrylamide Gel

Abstract

Publisher Summary This chapter discusses the immunoglobulin heterogeneity studied by isoelectric focusing in polyacrylamide gel. The extensive heterogeneity of immunoglobulins poses a major challenge to protein separation procedures. The very large number of antigenic determinants against which an immune response can be mounted points to the potential synthesis of an immense variety of immunoglobulin molecules; moreover, from a number of other considerations, it is clear that many different antibody molecules may be elaborated specific for the same antigenic determinants. In practice, however, the extent of heterogeneity of an immunoglobulin or a purified antibody preparation has not been directly measurable. The technique of isoelectric focusing (I.E.F.) as applied in thin layers of polyacrylamide gel permits, for the first time, the direct analysis of immunglobulin heterogeneity. The chapter discusses the potential of this I.E.F. technique for analyzing immunoglobulins and illustrates this with the example of its application to the problem of the homogeneity of the product of the single plasma cell clone