Der Effekt von gamma-Bestrahlung auf die ICAM-1 Expression bei humanen koronaren Gefäßwandzellen
LicenseStandard (Fassung vom 03.05.2003)
Background: Low dose irradiation occurs according the suggestion of many authors to extend the irradiation area in vascular brachytherapy to minimize the edge effect. Recently our group has reported that LDI stimulates proliferation of smooth muscle cells of human coronary plaque material, but has no effect on mRNA expression of the intercellular adhesion molecule-1 (ICAM-1) in human monocytes. The current study investigates the effect of gamma-irradiation on mRNA expression of ICAM-1 in human coronary vascular cells. Methods: Human coronary endothelial cells (HCAEC), human umbilical endothelial cells (HUVEC), and human coronary smooth muscle cells (HCMSMC) were cultured and identified. 24 h after seeding gamma-irradiation with a dose of 0.5 Gy, 1 Gy, 10 Gy, 20 Gy, and 30 Gy was carried out. 20 h after irradiation expression of ICAM-1 was stimulated by a 6 h stimulus with TNF-alpha (20 ng/ml). Corresponding controls with TNF-alpha stimulus without prior irradiation were done. Isolation of total RNA (3 x 10-6 cells) was carried out using RNEasy Mini Kit (Qiagen). Relative band density of ICAM-1 mRNA of irradiated and stimulated cells was compared with non-irradiated cells after mere TNF-alpha stimulus. Results: In HCAEC and HCMSMC a stimulation of ICAM-1 mRNA was detected after irradiation, no matter which dose was applied. After low dose irradiation (0.5 Gy and 1 Gy) the stimulating effect was pronounced. Significant differences were found in HCAEC after irradiation with 1 Gy. In HUVEC a stimulation of ICAM-1 mRNA expression was found after irradiation with 0.5 Gy and 1 Gy. In comparison to the stimulation seen after irradiation of HCAEC and HCMSMC the effect was less intense. After irradiation of HUVEC with doses of 10 Gy, 20 Gy, and 30 Gy an inhibition of ICAM-1 mRNA expression was found. Conclusions: Stimulation of ICAM-1 mRNA expression after LDI of human coronary vascular cells may be, at least partially, an in vitro equivalent of the edge effect described after LDI in vivo.
Subject HeadingsGammabestrahlung [GND]
Tumor-Nekrose-Faktor <alpha> [GND]