A sensitive method for the analysis of urinary proteoglycans

Twelve control persons excreted 282 +/- 106 micrograms proteoglycans/l urine (+/- S.D.) in a random urine sample. For four patients with a clinical proteinuria of 1.1 to 5.8 g/l, the excretion varied between 52 and 387 micrograms/l. The control proteoglycan pattern in an electrophoretic analysis on polyacrylamide gel and stained with digoxigenin followed by incubation with digoxigenin antibodies, consisted of a major band with a molecular weight of 100,000. It comigrated with a similar band in the serum proteoglycan pattern. The control pattern contained also lighter fractions with molecular weights between 50,000 and 28,000. The major proteoglycan band remained unchanged in the pattern of the proteinuric patients while conspicuous new bands appeared in the pattern of patients with proteinuria greater than 1.9 g/l. They seem to be of urinary tract origin as they had no counterparts in the serum proteoglycan pattern.