Lipoprotein(a) [Lp(a)] has been labelled the most atherogenic lipoprotein in man. Current laboratory methods for Lp(a) employ immuno-quantitation of its apolipoprotein [apo(a)]. Because these methods are hampered by cross-reactivity to plasminogen, apo(a) isoform dependence, antibody heterogeneity, and lack of standardization, none of them is FDA-approved. One third of Lp(a)'s mass is cholesterol, and only one tenth is apo(a). We propose the development of a quantitative laboratory, and a semi- quantitative screening method for Lp(a) cholesterol [Lp(a)-C]. The methods exploit Lp(a)'s unique high content of carbohydrate, e.g. sialic acid. Lp(a) is separated from other lipoproteins by binding of its peripheral carbohydrate structures to a specific solid-supported lectin, and analyzed by highly sensitive enzymic cholesterol methods.
