Chemotactic activity of elastin-derived peptides.

TLDR

Elastin-derived peptides were produced by digesting human aortic and bovine ligament elastin with human neutrophil elastase and then tested for chemotactic activity. At 100 µg protein/ml, elastin digests were nearly as active for monocytes as saturating complement-derived chemotactic activity, with maximal activity in 14,000–20,000 Da fractions rich in desmosine cross‑links, and purified desmosine also attracted monocytes, while the activity was inhibited by serum and anti‑elastin antibodies, indicating that elastin degradation products recruit inflammatory cells in emphysema.

Abstract

Elastin-derived peptides, produced by digesting human aortic elastin and bovine ligament elastin with human neutrophil elastase, were tested for chemotactic activity. At 100 micrograms protein/ml, elastin digests were nearly as active for monocytes as saturating amounts of complement-derived chemotactic activity. Neutrophils and alveolar macrophages showed less response to elastin peptidces than did monocytes. Fractionation of the digests by gel filtration chromatography disclosed that maximal chemotactic activity eluted in fractions corresponding to 14,000-20,000 mol wt containing most of the desmosine cross-links in the digests. Whole human serum and rabbit anti-elastin immunoglobulin inhibited the chemotactic activity. Purified desmosine also showed chemotactic activity for monocytes, maximal at 10 nM. These findings suggest that elastin-degradation products enriched in cross-linking regions recruit inflammatory cells in vivo and that elastin proteolysis, characteristic of emphysema, may be a signal for recruitment of mononuclear phagocytes into the lungs.