Immunochemical and enzymatic studies on the soluble antigens of normal human kidney

The antigenic composition of the soluble extract from normal human kidney was determined with the combined techniques of immunological absorption, immuno-diffusion and immunoelectrophoresis. The kidney extract contained at least eleven non-serum, tissue antigens; some of them were found in the extracts of other organs, but three were kidney-specific. None of the soluble tissue antigens from human kidney was characterized as a lipoprotein; however, three of them stained with the reagent for glycoproteins. Esterase activities were also demonstrated in four non-serum, renal antigens, one of which was present only in the kidney extract and absent in the other organs extracts.