Elastase-type activities were found associated with lipoprotein fractions in human serum. A metallo-protease hydrolysing Suc(Ala)3 PNA and soluble elastin peptides was isolated from apoHDL by Sepharose-elastin chromatography. Polyacrylamide gel electrophoresis and immunoelectrophoresis indicated that this elastase-type activity was associated with apoA1.
