Mucopolysaccharides of whole human spleens in generalized amyloidosis.

Amyloidosis is a morphological concept (2) the diagnosis of which has been based on histo- logical critera (3). "Primary" and "secondary" amyloidosis and the forms of amyloidosis seen in conjunction with familial Mediterranean fever (FMF) and myeloma are all grouped under one name because of morphological similarities, although it is not certain that they represent a single disease. Electron microscopy has, however, revealed characteristic fibrils in all forms of amy- loidosis (4-6). Some of the stains that are taken up by amyloid material suggest that it may con- tain mucopolysaccharides (MPS) (7). Never- theless, chemical investigations have not previously shown any marked increase in extractable metachromatic material (8) nor in uronic acid (9) or sulfate-containing compounds (10), al- though heparan sulfate has been isolated from a few amyloid-bearing organs The pur- pose of the present study was a systematic chemical investigation of the MPS in an extended se- ries of cases and controls that has not hitherto been carried out.