[Features of the isoelectric distribution of human immunoglobulin G depending on the type of light chains].

Physicochemical properties of immunoglobulin G of human blood serum under different states of the organism have been studied. Certain regularity of pH-distribution of IgG molecules which include different kinds of light chains has been first demonstrated using the method of isoelectrical focusing in a horizontal multicell apparatus of own construction in the system of ampholines (LKB, Sweden). This distribution changes directly depend on the peculiarities of the pathological process. The increase of a share of kappa-containing molecules of serum IgG in the alkali (by isopoints) fractions for the acute period of autoimmune thyroiditis, nodular toxic goiter, insulin depending diabetes mellitus, systemic lupus erythematosus is observed. The decrease of this parameter is characteristic under diffuse toxic goiter, gastric and duodenal peptic ulcer. IgG which takes direct part in immunocomplex processes differs from serum one by its physicochemical properties. In particular, this is manifested in the distribution of separate fractions in isospectrum, in the composition with other proteins and correlation of the types of light chains in them depending on concrete pathology.