Evaluation of lipoproteins and apolipoproteins in serum of a Tangier patient by micro-scale two-dimensional electrophoresis.

We examined lipoproteins and apolipoproteins in serum of a Tangier-disease patient. We used three different techniques of micro-scale two-dimensional electrophoresis: (a) no denaturants; (b) with sodium dodecyl sulfate (SDS) used only in the slab gel electrophoresis; (c) and with urea and a detergent used in isoelectric focusing and with SDS in slab gel electrophoresis. By technique a, an extremely low concentration of high-density lipoproteins (HDL) in the Tangier serum was seen, and lipoproteins that cannot form HDL complexes were detected as multiple spots in the acidic (pl 4 approximately 5) and relatively low apparent molecular mass (20,000 approximately 80,000) region. By technique b, Tangier low-molecular-mass lipoproteins were dissociated into their constituent apolipoproteins, and we observed a higher proportion of apoC-III, together with lower proportions of apoA-I and apoA-II, than in the normal HDL fraction. Technique c showed the total content of apolipoproteins in the whole Tangier serum, as several workers have reported. The presence of low-molecular-mass lipoproteins and a high concentration of apoC-III in this lipoprotein fraction characterized the Tangier serum.