Differential expression of double-band apolipoprotein(a) phenotypes in healthy Spanish subjects detected by SDS–agarose immunoblotting

• Published in: Clinica chimica acta 1998-10, Vol.277 (2), p.191-205
• Main Authors: Martı́n, Silvia, Ladona, Margarita G, Pedro-Botet, Juan, Covas, Marı́a I, Rubiés-Prat, Juan
• Format: Article
• Language: English
• Subjects: Adult; Aged; Aged, 80 and over; Analytical, structural and metabolic biochemistry; Apo(a) phenotypes; Apolipoproteins - blood; Apoprotein(a); Biological and medical sciences; Fundamental and applied biological sciences. Psychology; Human apolipoprotein(a) polymorphism; Humans; Immunoblotting; Immunoblotting - methods; Lipoprotein(a); Lipoproteins, myelin; Male; Middle Aged; Phenotype; Protein expression; Proteins; Reference Values; Reproducibility of Results; SDS–SAGE; Sepharose; Sodium Dodecyl Sulfate; Spain - ethnology
• ISSN: 0009-8981; 1873-3492
• DOI: 10.1016/S0009-8981(98)00126-0

A sodium dodecyl sulphate-agarose apolipoprotein(a) [apo(a)] phenotyping method was set up to attain accurate scanning densitometry of proteins. Serum samples from 99 healthy Spanish men were analysed and twenty-five different apo(a) isoforms (12 to 37 kringle 4 repeats) were detected. Double-band phenotypes accounted for 39.4% ( n=39) and three different patterns of protein expression were identified: pattern A (20.5% of double-band phenotyped samples) predominantly expressed the highest molecular weight isoform; pattern B (53.9%) mainly the lowest molecular weight isoform, and pattern AB (25.6%), expressed both isoforms equally. A significant linear association between expression pattern and lipoprotein(a) [Lp(a)] concentration ≥0.30 g/l was observed. Single-band phenotyped samples ( n=60) were stratified according to apo(a) kringle 4 repeat categories and showed that 90% of isoforms