Lipoprotein-acid mucopolysaccharide complexes of human atherosclerotic lesions.

Lipoprotein-acid mucopolysaccharide complexes occurring in different types of human atherosclerotic lesions were isolated and partially characterized. Complexes from fatty streaks and fibrous plaques were extracted from pooled tissues with 0.15 M NaCl, purified by gel filtration, and fractionated by ultracentrifugation. Both low and very low density lipoproteins were present; low density lipoprotein was predominant. The complexes were analyzed for uronic acid, cholesterol, phospholipid, and Ca-2+ contents; there was no significant difference in the relative molar ratios between complexes from fatty streaks and fibrous plaques. Acid mucopolysaccharides were isolated from the complexes and identified by electrophoresis and enzymatic studies. Chondroitin sulfate C and hyaluronic acid were found in complexes from fatty streaks and fibrous plaques. Heparin was detected only in fibrous plaques.