Shirahata T, Muroya N, Ohta C, Goto H, Nakane A
Department of Veterinary Microbiology, Obihiro University of Agriculture and Veterinary Medicine, Hokkaido, Japan.
Microbiol Immunol. 1993;37(7):583-90. doi: 10.1111/j.1348-0421.1993.tb01680.x.
The lymphokine production by pregnant mice infected with a lethal dose of Toxoplasma gondii was evaluated in comparison with that by virgin mice infected with a sublethal dose of this protozoan parasite. Splenocytes taken from mice before and on the day after infection produced considerable amounts of IL-2 in response to concanavalin A (Con A) stimulation, but the titers rapidly declined in both pregnant and virgin mice as infection progressed. A trace amount or undetectable level of IL-2 was produced by splenocytes from acutely infected mice when stimulated with Toxoplasma lysate antigen (TLA). In contrast to the kinetics of IL-2 production, the levels of IFN-gamma produced by splenocytes cultured with Con A or TLA increased steadily in the later stage of infection in both pregnant and virgin mice. Thus, the response to Con A or TLA of splenocytes to produce IL-2 and IFN-gamma differed strikingly in acute toxoplasmosis in mice. The administration of rHuIL-2 resulted in a significant decrease in the mortality of pregnant mice infected with a lethal dose of Toxoplasma. The combination of rHuIL-2 and rMuIFN-gamma increased the survival rate slightly but not significantly compared with pregnant mice receiving either rHuIL-2 or rMuIFN-gamma. Moreover, exogenously administered rHuIL-2 enhanced the production of both IFN-alpha and IFN-gamma in the bloodstreams of pregnant mice, in accordance with the decreased mortality. These results indicate that IL-2 may play a significant role in modulating the host defense against Toxoplasma infection in pregnant mice.
将感染致死剂量刚地弓形虫的怀孕小鼠的淋巴细胞因子产生情况，与感染亚致死剂量这种原生动物寄生虫的未孕小鼠的情况进行了比较评估。在感染前及感染后一天从小鼠获取的脾细胞，在伴刀豆球蛋白A（Con A）刺激下产生大量白细胞介素-2（IL-2），但随着感染进展，怀孕小鼠和未孕小鼠体内的IL-2滴度均迅速下降。用弓形虫裂解物抗原（TLA）刺激时，急性感染小鼠的脾细胞产生微量或检测不到水平的IL-2。与IL-2产生的动力学情况相反，在怀孕小鼠和未孕小鼠感染后期，用Con A或TLA培养的脾细胞产生的γ干扰素（IFN-γ）水平均稳步升高。因此，在小鼠急性弓形虫病中，脾细胞对Con A或TLA产生IL-2和IFN-γ的反应存在显著差异。给予重组人IL-2可显著降低感染致死剂量刚地弓形虫的怀孕小鼠的死亡率。与单独接受重组人IL-2或重组小鼠IFN-γ的怀孕小鼠相比，重组人IL-2和重组小鼠IFN-γ联合使用可使存活率略有提高，但无显著差异。此外，外源性给予重组人IL-2可增强怀孕小鼠血液中α干扰素（IFN-α）和IFN-γ的产生，这与死亡率降低一致。这些结果表明，IL-2可能在调节怀孕小鼠对弓形虫感染的宿主防御中发挥重要作用。
