Antibodies to Insoluble and Solubilized Elastin

A major problem in elastin biochemistry has been the development of methods for quantifying elastin synthesis and degradation. Significant progress has been made with the development of immunoassays using antisera prepared against tropoelastin and various forms of elastin. This chapter describes the preparation of antisera to insoluble or solubilized elastin and the use of the antisera in immunoassays. Tropoelastin and elastin are multideterminant antigens, and their antisera are inevitably heterogeneous. In addition, structural dissimilarities between the two proteins result in serological nonidentity. Notwithstanding these differences, insoluble elastin and tropoelastin share enough common determinants so that antiserum to elastin cross-reacts with tropoelastin and can be a valuable tool in studying tropoelastin biosynthesis. In addition, anti-elastin antibodies recognize elastin peptides released from the intact protein by proteolysis and can be useful to investigate elastin degradation. The use of elastin as an antigen, instead of tropoelastin, offers the advantages that elastin is easy to purify, is available in larger quantities than tropoelastin, and is not readily susceptible to proteolysis and degradation.