Reactions of Localizing Anti-Kidney Antibodies with Tissues of Various Species

Abstract

Reactions of localizing anti-kidney antibodies with kidney (and liver) of homologous and heterologous species were studied by the “paired label technique,” using mixtures of I¹²⁵-labeled antibody and I¹³¹-labeled normal globulin. The kidney localizing activity of rabbit antirat kidney antibodies is largely removed by absorption with rat kidney sediment and is removed to various lesser extents by prior absorption with kidney sediments of other species. Anti-kidney antibodies formed in rabbits against sheep kidney and antibodies formed in goats and guinea pigs against rabbit kidney localize in vivo to a small extent in kidneys of rats. Cross-localization reactions become much more apparent by the use of antibodies purified by absorption on and elution from kidney and liver sediments. Purified antibody preparations react differently with various tissue antigens, indicating that the purification procedure selects certain populations of anti-kidney antibodies out of the much more heterogeneous original mixture. Each population cross-reacts preferentially with the tissue antigens of the species used for purification. A small degree of cross-reaction was observed even with kidney of the species used for antibody production. This was shown only after purification on this tissue sediment. The cross-reaction of anti-rat kidney antibody with kidneys of heterologous species may be useful in the characterization of the antigens responsible for the specific antibody localization in the rat kidney.