Isolation and characterization of a rabbit non-tissue specific autoantigen which is shared by kidney, heart, adrenal and liver.

An antigen that can be derived from rabbit kidney can be identified by use of suitable rabbit antisera as being non-tissue specific in addition to being an autoantigen, since it had been found to be distributed in kidney, heart, adrenal and liver. The purification of this autoantigen has been accomplished by successive use of four different methods. These were the salting out with ammonium sulphate, gel filtration on Sephadex G-200, dialysis against distilled water, and chromatography on DEAE-cellulose. The heterogeneity of the products derived from the procedure at each step was analysed by means of analytical electrophoresis and ultracentrifugation, and also by gel diffusion precipitation. The final product was a homogeneous component, according to the criteria that were used. It had a sedimentation coefficient of 4.1S, suggesting a mol. wt of approximately 60,000. This autoantigen is of similar molecular size to several others that are, in contrast, adrenal specific or kidney specific.