El-Masry S, Lotfy M, Nasif W A, El-Kady I M, Al-Badrawy M
Molecular and Cellular Biology Department, Genetic Engineering and Biotechnology Research Institute, Minufiya University, Sadat City, Egypt.
Acta Microbiol Immunol Hung. 2007 Mar;54(1):65-77. doi: 10.1556/AMicr.54.2007.1.7.
Mycobacterium tuberculosis can cause life-threatening complications in which the immune response plays an important role. This study was designed to evaluate the serum levels of interleukin-18 (IL-18), interferon-gamma (IFN-gamma) and soluble Fas (sFas) in cases with pulmonary tuberculosis due to confirmed M. tuberculosis infection. The study comprised 50 patients with M. tuberculosis classified to 13 complicated cases and 37 uncomplicated patients. A significant (P<0.05) increase was found in the serum levels of IL-18, IFN-gamma and sFas in patients compared to controls and also in complicated cases compared to uncomplicated ones. Moreover, a positive significant correlation was found between serum levels of sFas with IL-18 (r=0.532, P<0.001), and with IFN-gamma (r=0.37, P=0.008) and lastly between serum levels of IL-18 with IFN-gamma (r=-0.612, P<0.001). It is concluded from these results with the recent observations that IFN-gamma levels are elevated after successful MTB treatment, suggest the possibility of enhanced Fas expression and then stimulating the infected macrophages to show an increased FasL-induced apoptosis. Modulation of FasL system by M. tuberculosis might represent an escape mechanism to evade the effect of apoptosis. Moreover, the elevated serum levels of IL-18, IFN-gamma and sFas can be considered as pathognomonic markers suggesting pulmonary tuberculosis especially in complicated cases.
结核分枝杆菌可引发危及生命的并发症，其中免疫反应起着重要作用。本研究旨在评估确诊为结核分枝杆菌感染的肺结核患者血清中白细胞介素-18（IL-18）、干扰素-γ（IFN-γ）和可溶性Fas（sFas）的水平。该研究纳入了50例结核分枝杆菌感染患者，分为13例复杂病例和37例非复杂病例。与对照组相比，患者血清中IL-18、IFN-γ和sFas水平显著升高（P<0.05），复杂病例与非复杂病例相比亦是如此。此外，sFas血清水平与IL-18之间呈显著正相关（r=0.532，P<0.001），与IFN-γ之间呈显著正相关（r=0.37，P=0.008），最后IL-18与IFN-γ血清水平之间呈显著负相关（r=-0.612，P<0.001）。从这些结果以及近期观察可得出结论，成功进行MTB治疗后IFN-γ水平升高，提示Fas表达增强进而刺激受感染巨噬细胞表现出FasL诱导的凋亡增加的可能性。结核分枝杆菌对FasL系统的调节可能代表一种逃避凋亡效应的机制。此外，血清中IL-18、IFN-γ和sFas水平升高可被视为提示肺结核的特征性标志物，尤其是在复杂病例中。
