Immunochemical heterogeneity of human plasma high density lipoproteins. Identification with apolipoprotein A-I- and A-II-specific monoclonal antibodies.

摘要: Three mouse monoclonal antibodies specific for human apolipoprotein (apo) A-I and one apo-A-II were characterized with respect to their binding of high density lipoprotein (HDL) particles in solution. The apo-A-II-specific antibody bound 85% 125I-HDL 100% soluble 125I-apo-A-II. However, none the apo-A-I-specific greater than 60% either HDL or apo-A-I. Technical issues such as limiting amounts antigen, radioiodination ligands, unavailability epitopes reaction antibody, selective apo-A-I isoforms, individual allotypic differences not responsible observed incomplete all results suggested existence intrinsic immunochemical heterogeneity both organized on well free validity this was supported by demonstrating that (i) increased occurred when each combined form an oligoclonal mixture, (ii) two single antibody. To understand basis expression HDL, hypotheses examined. first hypothesis these distinguished molecules from different synthetic sources substantiated. Two thoracic duct lymph enriched source intestinal culture supernatants hepatic cell line Hep G2 a HDL. second identified subpopulations size net particle charge, i.e. organizational heterogeneity, appeared provide best available explanation Relative three distinct demonstrated obtained gradient ultracentrifugation chromatofocusing. In light studies, we conclude there is intramolecular loci representing our antibodies. Such must be considered analysis biology physiology bearing chain.