Eksi S, Wassom D L, Powell M R
Department of Biological Sciences, Ohio University, Athens 45701, USA.
J Parasitol. 1996 Feb;82(1):59-65.
Survival of acute Trypanosoma cruzi infection by mice is influenced by genes inside and outside the major histocompatibility complex (MHC) and genes associated with resistance must be expressed in both the MHC and the genetic background or the host will die within a few weeks of infection. Both the levels and the kinetics of cytokine production have also been implicated as important factors for resistance. Antigen-stimulated spleen cells from mice that express the resistant H-2q MHC haplotype produced significantly more interferon (IFN)-gamma than did cells from mice that share the susceptible H-2k haplotype. But, spleen cells from susceptible and resistant mice produce similar levels of IFN-gamma when stimulated with concanavalin A. The kinetics of interleukin (IL)- 10 production by ConA (ConA)-stimulated spleen cell were inversely correlated with IFN-gamma levels throughout the course of acute infection in all mouse strains. Levels of IL-2 produced by ConA-stimulated spleen cells were also initially high (day 0) then decreased as acute infection progressed. Conversely, IL-4 production by ConA-stimulated spleen cells increased during infection, and mice that express the susceptible C3H background produced significantly more IL-4 than those that share the resistant B10 background. IL-2 production by lymph node cells from mice that express the susceptible C3H genetic background also declined during infection, while lymph node cells from B10 background mice showed a moderate increase in IL-2 secretion. These data suggest that both the levels and the kinetics of cytokine production may be genetically regulated and that cytokine responses are compartmentalized in the T. cruzi-infected host.
小鼠急性克氏锥虫感染的存活情况受主要组织相容性复合体(MHC)内外的基因影响,与抗性相关的基因必须在MHC和遗传背景中都得以表达,否则宿主将在感染后几周内死亡。细胞因子产生的水平和动力学也被认为是抗性的重要因素。表达抗性H-2q MHC单倍型的小鼠经抗原刺激的脾细胞产生的干扰素(IFN)-γ明显多于具有易感H-2k单倍型的小鼠的细胞。但是,用刀豆球蛋白A刺激时,易感和抗性小鼠的脾细胞产生的IFN-γ水平相似。在所有小鼠品系的急性感染过程中,刀豆球蛋白A(ConA)刺激的脾细胞产生白细胞介素(IL)-10的动力学与IFN-γ水平呈负相关。ConA刺激的脾细胞产生的IL-2水平最初也很高(第0天),然后随着急性感染的进展而下降。相反,ConA刺激的脾细胞产生的IL-4在感染期间增加,表达易感C3H背景的小鼠产生的IL-4明显多于具有抗性B10背景的小鼠。表达易感C3H遗传背景的小鼠的淋巴结细胞产生的IL-2在感染期间也下降,而B10背景小鼠的淋巴结细胞的IL-2分泌则适度增加。这些数据表明,细胞因子产生的水平和动力学可能受基因调控,并且在克氏锥虫感染的宿主中细胞因子反应是分区的。