Characterization of monocyte chemotactic protein-1 binding to human monocytes.
Monocyte chemotactic protein-1 (MCP-1) stimulates chemotaxis of peripheral blood monocytes. In order to understand the biologic basis of this specific activity, binding studies of 125I-MCP-1 were undertaken. MCP-1 showed saturable binding to monocytes. Scatchard analysis of the monocyte binding data indicate that there are approximately 1,600 high affinity binding sites per monocyte with a Kd = 1.1 nM. Studies with synthetic peptides constructed according to the MCP-1 amino acid sequence indicate that a synthetic peptide, MCP-1[13-35], stimulates monocyte migration and competes with native MCP-1 for binding sites. Inhibition of MCP-1 binding was tested with chemotactic connective tissue proteins. No inhibition of MCP-1 binding was observed with either collagen, elastin-derived peptides or fibronectin. These results identify a single class of unique high affinity MCP-1 binding sites that are likely to recognize a peptide domain on MCP-1 which include the amino acids within the region, 13-35.
Valente
A J
AJ
Department of Pathology, University of Texas Health Science Center, San Antonio 78284.
Rozek
M M
MM
Schwartz
C J
CJ
Graves
D T
DT
D000818:Animals; D000890:Anti-Infective Agents / Q000378:metabolism*; D001667:Binding, Competitive; D018932:Chemokine CCL2; D002630:Chemotactic Factors / Q000302:isolation & purification / Q000378:metabolism* / Q000494:pharmacology; D002634:Chemotaxis, Leukocyte / Q000187:drug effects; D003094:Collagen / Q000494:pharmacology; D004549:Elastin / Q000494:pharmacology; D005353:Fibronectins / Q000494:pharmacology; D006801:Humans; D066298:In Vitro Techniques; D007700:Kinetics; D007963:Leukocytes, Mononuclear / Q000502:physiology*; D009131:Muscle, Smooth, Vascular / Q000737:chemistry; D010215:Papio; D010446:Peptide Fragments / Q000494:pharmacology; D011485:Protein Binding
D000890:Anti-Infective Agents; D018932:Chemokine CCL2; D002630:Chemotactic Factors; D005353:Fibronectins; D010446:Peptide Fragments; D003094:Collagen; D004549:Elastin