Low density lipoproteins and immunoglobulins in human pleural effusions.

Pleural effusions in patients with bacterial pleurisy contain low density lipoproteins (33 per cent of the blood serum LDL-concentration on average) but almost no very-low density lipoproteins (about 1 percent of the blood serum VLDL-concentration on average). Immunoglobulins are present in large amounts forming a series declining from the IgG (70 per cent of the blood serum concentration, found in effusions) to the IgM (50 per cent of the blood serum concentration). The observations are discussed in relation to morphological aspects of molecular transport through the capillary wall, and the consequences of the LDL- and IgL-accumulation in pleural fluids are briefly discussed.

Two-dimensional immunoelectrophrophoretic pattern of low- and very-low-density lipoproteins, with particular reference to Fredrickson's type III.

I report the pattern of low-density lipoproteins (LDL) and very-low-density lipoproteins (VLDL) as revealed by two-dimensional (crossed) immunoelectrophoresis in hyperlipoproteinemia types, II, III, and IV, preliminarily diagnosed by means of a complex lipoprotein profile examination. The higher affinity of Oil Red stain for VLDL- than for LDL-immunoprecipitation zones is peculiar to this lipoprotein class, and crossed immunoelectrophoretograms may thus be helpful for laboratory diagnosis of types IIb and IV in problematic cases. The position and the medium affinity for Oil Red of "broad beta" zones appearing in immunoelectrophoretograms of type III hyperlipoproteinemia are suggested as useful criteria for the diagnosis of this condition. From the structural and staining characteristics of VLDL-immunoprecipitation zones, alteration of both composition and antigenic properties of VLDL in hyperlipoproteinemias IIb-IV is deduced. I present in detail the procedure for crossed immunoelectrophoresis as well as that for the lipoprotein profile examination used in this study.