Induction of monocyte chemoattractant protein-1 synthesis in human monocytes during transendothelial migration in vitro.
Monocyte chemoattractant protein-1 (MCP-1, or monocyte chemotactic and activating factor) plays important roles in the recruitment of monocytes and thus in the development of atherosclerosis. In this study, we determined whether MCP-1 synthesis was induced by the cellular interaction between monocytes and endothelial cells during the process of transendothelial migration. We found that when human peripheral blood monocytes (2.5 x 10(6) cells) and umbilical vein endothelial cells (HUVECs; 5.0 x 10(5) cells) were cocultured for 5 hours, 7.9 ng/mL MCP-1 was secreted into the medium, whereas when the two were cultured separately, MCP-1 levels were 1.0 and 0.9 ng/mL, respectively. Furthermore, the use of interleukin-1 beta (IL-1 beta)-pretreated HUVECs in cocultures induced twice the levels of MCP-1 as in unstimulated HUVEC culture. Conditioned medium had transendothelial chemotactic activity for monocytes, and this activity was completely abolished by addition of anti-MCP-1 antibody. Although MCP-1 mRNA levels were very low or undetectable in HUVECs or monocytes alone, message could be detected after 2 hours of coculture in total mRNA preparations from both monocytes and HUVECs. mRNA levels increased by 4 hours and had declined slightly by 24 hours. The rapid induction of message suggests that cell contact between monocytes and HUVECs induces the de novo synthesis of MCP-1 protein. Anti-interleukin (IL)-1 alpha/beta and anti-tumor necrosis factor-alpha antibodies, or anti-lymphocyte function-associated antigen-1 and very late antigen-4 antibodies, had little or no inhibitory effects on MCP-1 secretion by cocultures.(ABSTRACT TRUNCATED AT 250 WORDS)
Takahashi
M
M
Department of Cardiology, Jichi Medical School, Tochigi, Japan.
Masuyama
J
J
Ikeda
U
U
Kasahara
T
T
Kitagawa
S
S
Takahashi
Y
Y
Shimada
K
K
Kano
S
S
D015815:Cell Adhesion Molecules / Q000032:analysis; D002465:Cell Movement; D002478:Cells, Cultured; D018932:Chemokine CCL2; D002630:Chemotactic Factors / Q000096:biosynthesis*; D017077:Culture Media, Conditioned; D016207:Cytokines / Q000378:metabolism; D004730:Endothelium, Vascular / Q000166:cytology*; D006801:Humans; D009000:Monocytes / Q000378:metabolism*; D012333:RNA, Messenger / Q000032:analysis
D015815:Cell Adhesion Molecules; D018932:Chemokine CCL2; D002630:Chemotactic Factors; D017077:Culture Media, Conditioned; D016207:Cytokines; D012333:RNA, Messenger