Increased expression of interleukin-10 in unstable plaque obtained by directional coronary atherectomy.
OBJECTIVE
The present study investigates the expression and localization of interleukin (IL)-10, an important anti-inflammatory cytokine, in atherectomy specimens from patients with stable and unstable angina.


RESULTS
Twenty-two patients with stable angina and 21 with unstable angina who underwent directional coronary atherectomy for de novo lesions were studied. The atherectomy specimens were morphologically assessed and immunohistochemically stained with antibodies for IL-10, macrophages, smooth muscle cells, and endothelial cells. The localization and immunopositive areas were evaluated using an image analysing system. Immunoreactivity for IL-10 was detected in coronary plaques, especially in macrophages. Immunopositive areas of macrophages and IL-10, as well as the incidence of thrombus formation, were significantly greater in specimens from patients with unstable angina than in those from patients with stable angina (macrophages, P<0.001; IL-10, P<0.05; thrombus formation, P<0.05; respectively). Even after adjustment, IL-10 expression and the incidence of thrombus formation were significantly greater in the unstable angina group (P<0.05, each). The immunoreactivities for smooth muscle cells and endothelial cells did not differ between the two groups.


CONCLUSIONS
IL-10 was more frequently expressed in specimens from patients with unstable angina. This finding might contribute to a better understanding of plaque instability.
Nishihira
Kensaku
K
First Department of Internal Medicine, University of Miyazaki, 5200 Kihara, Kiyotake, Miyazaki 889-1692, Japan.
Imamura
Takuroh
T
Yamashita
Atsushi
A
Hatakeyama
Kinta
K
Shibata
Yoshisato
Y
Nagatomo
Yoshitatsu
Y
Date
Haruhiko
H
Kita
Toshihiro
T
Eto
Tanenao
T
Asada
Yujiro
Y
D000368:Aged; D000787:Angina Pectoris / Q000378:metabolism*; D000789:Angina, Unstable / Q000378:metabolism; D017225:Atherectomy, Coronary; D003324:Coronary Artery Disease / Q000378:metabolism*; D003328:Coronary Thrombosis / Q000209:etiology; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D016753:Interleukin-10 / Q000378:metabolism*; D008297:Male; D008875:Middle Aged
D016753:Interleukin-10