Apolipoproteins in human biopsied nephrotic kidneys.

Using monospecific antibodies to purified human apolipoproteins, immunofluorescence microscopy of renal biopsies from 4 patients with nephrotic syndrome revealed apolipoprotein (apo) AI, apo CIII and apo B (LDL) in lysosomes of the proximal tubular cells. This supports the hypothesis that there is increased filtration of both high density lipoproteins (HDL) and low density lipoproteins (LDL) with partial reabsorption by the tubules, thus affecting the serum lipoprotein levels.