IDENTIFICATION OF CRYPTIC PEANUT AGGLUTININ-REACTIVE SITES IN HUMAN LIPOPROTEIN(A)

After treatment of human lipoprotein(a) (Lp(a)) with neuraminidase, fo rmerly cryptic sites became available for binding to peanut agglutinin (PNA) lectin and a Thomsen-Friedenreich antigen (T-antigen)-specific monoclonal antibody. The PNA-reactive sites were localized to the apo( a) moiety of Lp(a) and O-specific carbohydrate side chains, Lp(a) with larger isoforms of apo(a) contained more potential PNA reactivity per molecule of Lp(a) apoB than did smaller isoforms. Very low density li poproteins (VLDL), low density lipoproteins (LDL), and high density li poproteins (HDL) did not contain comparable amounts of the cryptic PNA -reactive sites.