Interleukin-8 production by macrophages from atheromatous plaques.
Interleukin-8 (IL-8) is a chemotactic peptide produced by macrophages that may be involved in the recruitment of inflammatory cells into atherosclerotic plaques. In vitro, IL-8 production by macrophages isolated from carotid plaques (1240 +/- 510 pg.10(5) cells-1.24h-1, mean +/- SEM, n = 6) and noncarotid plaques (4312 +/- 1588 pg.10(5) cells-1.24 h-1, n = 9) was significantly greater than IL-8 production by blood monocytes isolated from the same patients (526 +/- 278 pg.10(5) cells-1.24 h-1, n = 6, P < .05 and 726 +/- 384 pg.10(5) cells-1.24 h-1, n = 9, P < .01, respectively). IL-8 produced by atherosclerotic macrophages was demonstrated to be biologically active in a neutrophil chemotaxis assay. IL-8 mRNA was detectable in plaque macrophages and blood monocytes from these patients, but blood monocytes from normal donors did not exhibit detectable IL-8 mRNA. IL-8 mRNA was localized in macrophage-rich areas of atherosclerotic plaques by in situ hybridization. These studies demonstrate that macrophages from atherosclerotic plaques show an enhanced capacity to produce IL-8 compared with normal and patient blood monocytes and that macrophages are a major site of IL-8 mRNA production in atherosclerotic plaques. These results provide further evidence for a proinflammatory role for macrophages in atherosclerosis.
Apostolopoulos
J
J
Monash University Department of Medicine, Monash Medical Centre, Victoria, Australia. Jim.Apostolopoulos@med.monash.edu.au
Davenport
P
P
Tipping
P G
PG
D000368:Aged; D000369:Aged, 80 and over; D001161:Arteriosclerosis / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D001483:Base Sequence; D005260:Female; D015870:Gene Expression; D006801:Humans; D016209:Interleukin-8 / Q000096:biosynthesis* / Q000235:genetics; D008264:Macrophages / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D009000:Monocytes / Q000378:metabolism; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics
D016209:Interleukin-8; D012333:RNA, Messenger