ABSTRACT
The first data concerning the rat serum proteins were obtained by Grabar and Courcon 1 and Escribano and Grabar, 2 using the immunoelectrophoretic analysis. They identified two lines of precipitation in the gammaglobulin area. Later, Arnason et al. 3-4 found three proteins with antibody activity in rat serum and called them IgM, IgX, and IgG. IgG were further divided into three subclasses with the IgA class clearly set apart. Then, a fourth IgG subclass, as well as the IgE and the IgD were found.
