Redistribution of amyloid deposits.

After 21 daily subcutaneous injections of 0.5 ml 10% casein, CBA/J mice were left untreated and evaluated periodically for 6 months for the development of amyloid in spleens, livers, and kidneys. At the end of the amyloid-inducing regimen, the mice developed moderate to heavy splenic amyloid, trace to light hepatic amyloid, and virtually no renal amyloid. Renal amyloid appeared about 2 months after cessation of the casein and then increased steadily, while splenic and hepatic amyloid gradually diminished. Six months after the cessation of casein, moderate amyloid deposits were observed in the kidneys whereas no, or only traces of, amyloid remained in spleens and livers. This renal amyloid was localized predominantly in the peritubular area and differed from the renal amyloid seen in rapidly induced disease, when it localizes dominantly in glomeruli. This phenomenon is interpreted in the light of possible redistribution of amyloid deposits from organ to organ, and the clinical and investigative significances of this possibility and others are discussed.