Purification of a monocyte chemotactic factor secreted by nonhuman primate vascular cells in culture.
A protein chemotactic for peripheral blood monocytes (SMC-CF) of potential importance in their recruitment to the arterial intima in atherogenesis was purified from serum-free medium conditioned by cultured baboon aortic medial smooth muscle cells. The purification of SMC-CF was monitored by a filter assay using human peripheral blood mononuclear cells and was achieved by batch separation on a cation-exchange gel followed by gel permeation chromatography, ion-exchange high-performance liquid chromatography (HPLC), and reversed-phase HPLC. The overall recovery was approximately 10% of the initial activity and yielded 0.5-1 microgram of SMC-CF/L of conditioned medium. On analytical sodium dodecyl sulfate-polyacrylamide gel electrophoresis, SMC-CF migrated as a monomeric protein with an apparent molecular weight of 14,500. A dose-dependent relationship was observed between SMC-CF concentration and monocyte chemotactic activity, with maximal and half-maximal biologic activity being observed at approximately 5 and 0.1 nM, respectively. Cultured baboon aortic smooth muscle cells also express the genes for both the A and B polypeptide chains of platelet-derived growth factor, which has been reported to be chemotactic for blood monocytes and neutrophils [Deuel, T. F., Senior, R. M., Huang, J. S., & Griffin, G. L. (1982) J. Clin. Invest. 69, 1046-1049]. Amino acid composition analyses indicate that SMC-CF is not derived either from polypeptide chain of this growth factor or from certain potentially chemotactic connective tissue proteins.
Valente
A J
AJ
Department of Pathology, University of Texas Health Science Center, San Antonio 78284.
Graves
D T
DT
Vialle-Valentin
C E
CE
Delgado
R
R
Schwartz
C J
CJ
D000596:Amino Acids / Q000032:analysis; D000818:Animals; D002478:Cells, Cultured; D002630:Chemotactic Factors / Q000302:isolation & purification* / Q000378:metabolism; D002850:Chromatography, Gel; D002851:Chromatography, High Pressure Liquid; D003470:Culture Media; D004591:Electrophoresis, Polyacrylamide Gel; D009000:Monocytes / Q000502:physiology*; D009131:Muscle, Smooth, Vascular / Q000032:analysis*; D010215:Papio; D011506:Proteins / Q000032:analysis
D000596:Amino Acids; D002630:Chemotactic Factors; D003470:Culture Media; D011506:Proteins