ELASTIN-DERIVED PEPTIDE INDUCES MONOCYTE CHEMOTAXIS BY INCREASING INTRACELLULAR CYCLIC-GMP LEVEL AND ACTIVATING CYCLIC-GMP DEPENDENT PROTEIN-KINASE

An elastin-derived peptide with an average molecular mass of 25 kDa wa s shown to induce monocyte chemotaxis at the optimal concentration of 10(-1) mu g/ml. Homologous deactivation test showed that monocytes exp osed to the elastin-derived peptide at 10(-1) mu g/ml lost their chemo tactic responsiveness when reexposed to the same stimulus. In conjunct ion with chemotactic response to the elastin-derived peptide, intracel lular guanosine 3', 5'-monophosphate (cGMP) levels were enhanced but i ntracellular adenosine 3', 5'-monophosphate (cAMP) levels were not. Th e monocyte migration induced by the elastin-derived peptide was inhibi ted by cGMP dependent protein kinase (PKG) inhibitor, but not by cAMP dependent protein kinase inhibitor and protein kinase C inhibitor. The se results suggest that the elastin-derived peptide induces monocyte c hemotaxis by increasing the level of cGMP, followed by activating PKG.