Suppression of CD4+ T-Cells in the Spleen of Mice Infected with Toxoplasma gondii KI-1 Tachyzoites
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초록
Toxoplasma gondii KI-1, a recent new isolate from Korea, shows similar pathogenicity and infectivity to mice compared to the virulent RH strain. To understand characteristics of host immunity, including immune enhancement or suppression, we investigated proliferative responses and phenotypes of spleen cells. In addition, kinetics of IFN-g, a Th1cytokine, was examined in BALB/c mice up to day 6 post-infection (PI). Intraperitoneal injection of mice with 103 KI-1 tachyzoites induced significant decreases (P < 0.05) in proliferative responses of spleen cells. This occurred at days 2-6 PI even when concanavalin A (con A) was added and when stimulated with KI-1 antigen, suggesting suppression of the immunity. CD4+ T-cells decreased markedly at day 2 PI (P < 0.05), whereas CD8+ T-cells, NK cells, and macrophages did not show significant changes, except a slight, but significant, increase of CD8+ T-cells at day 6 PI. The capacity of splenocytes to produce IFN-g by con A stimulation dropped significantly at days 2-6 PI. These results demonstrate that intraperitoneal injection of KI-1 tachyzoites can induce immunosuppression during the early stage of infection, as revealed by the decrease of CD4+ T-cells and IFN-g.
Abstract
Toxoplasma gondii KI-1, a recent new isolate from Korea, shows similar pathogenicity and infectivity to mice compared to the virulent RH strain. To understand characteristics of host immunity, including immune enhancement or suppression, we investigated proliferative responses and phenotypes of spleen cells. In addition, kinetics of IFN-g, a Th1cytokine, was examined in BALB/c mice up to day 6 post-infection (PI). Intraperitoneal injection of mice with 103 KI-1 tachyzoites induced significant decreases (P < 0.05) in proliferative responses of spleen cells. This occurred at days 2-6 PI even when concanavalin A (con A) was added and when stimulated with KI-1 antigen, suggesting suppression of the immunity. CD4+ T-cells decreased markedly at day 2 PI (P < 0.05), whereas CD8+ T-cells, NK cells, and macrophages did not show significant changes, except a slight, but significant, increase of CD8+ T-cells at day 6 PI. The capacity of splenocytes to produce IFN-g by con A stimulation dropped significantly at days 2-6 PI. These results demonstrate that intraperitoneal injection of KI-1 tachyzoites can induce immunosuppression during the early stage of infection, as revealed by the decrease of CD4+ T-cells and IFN-g.
참고문헌 (24)
- Gazzinelli RT, "Parasite-induced IL-12 stimulates early IFN-g synthesis and resistance during acute infection with Toxoplasma gondii", J Immunol, 153, pp.2533~2543 (1994)
- Bhopale GM, "Pathogenesis of toxoplasmosis", Comp Immunol Microbiol Infect Dis, 26, pp.213~222 (2003)
- Denkers EY, "Regulation and function of T-cellmediated immunity during Toxoplasma gondii infection", Clin Microbiol Rev, 11, pp.569~588 (1998)
- Jones JL, "Toxoplasma gondii infection in the United States, 1999-2000", Emerg Infect Dis, 9, pp.1371~1374 (2003)
- Choi WY, "Toxoplasma antibody titers by indirect latex agglutination test in patients of Kangnam St. Mary’s Hospital and Cheju Medical Center", Korean J Parasitol, 27, pp.171~175 (1989)
- Choi WY, "Foodborne outbreaks of human toxoplasmosis", J Infect Dis, 175, pp.1280~1282 (1997)
- Jong-YilCHAI, "Laboratory passage and characterization of an isolate of Toxoplasma gondii from an ocular patient in Korea", The Korean Journal of Parasitology, 41(3), pp.147~154 (2003), 대한기생충학회
- Aifen Lin, "Genetic characteristics of the Korean isolate KI-1 of Toxoplasma gondii", The Korean Journal of Parasitology, 43(1), pp.27~32 (2005), 대한기생충학회
- Gazzinelli R, "Simultaneous depletion of CD4+ and CD8+ T lymphocytes is required to reactivate chronic infection with Toxoplasma gondii", J Immunol, 149, pp.175~180 (1992)
- Denkers EY, "From cells to signaling cascades: manipulation of innate immunity by Toxoplasma gondii", FEMS Immunol Med Microbiol, 39, pp.193~203 (2003)
- Suzuki Y, "Interferong: the major mediator of resistance against Toxoplasma gondii", Science, 240, pp.516~518 (1988)
- Suzuki Y, "Importance of endogenous IFN-g for prevention of toxoplasmic encephalitis in mice", J Immunol, 143, pp.2045~2050 (1989)
- Shin EH, "Use of monoclonal antibodies for flow cytometric detection of intracellular Toxoplasma gondii in murine splenic lymphocytes", J Parasitol, 90, pp.161~166 (2004)
- Channon JY, "Attachment ligands of viable Toxoplasma gondii induce soluble immunosuppressive factors in human monocytes", Infect Immun, 67, pp.2547~2551 (1999)
- Wei S, "Toxoplasma gondii-infected human myeloid dendritic cells induce T-lymphocyte dysfunction and contact-dependent apoptosis", Infect Immun, 70, pp.1750~1760 (2002)
- 이은정, "Suppressed Production of Pro-inflammatory Cytokines by LPS-Activated Macrophages after Treatment with Toxoplasma gondii Lysate", The Korean Journal of Parasitology, 46(3), pp.145~151 (2008), 대한기생충학회
- Kanková S, "Modulation of immunity in mice with latent toxoplasmosis-the experimental support for the immunosuppression hypothesis of Toxoplasmainduced changes in reproduction of mice and humans", Parasitol Res, 107, pp.1421~1427 (2010)
- Buzoni-Gatel D, "Toxoplasma gondii and subversion of the immune system", Trends Parasitol, 22, pp.448~452 (2006)
- Shin EH, "T-helper-1 and T-helper-2 immune responses in mice infected with the intestinal fluke Neodiplostomum seoulense: their possible roles in worm expulsion and host fatality", J Parasitol, 93, pp.1036~1045 (2007)
- Choi WY, "Detection of antibodies in serum and cerebrospinal fluid to Toxoplasma gondii by indirect latex agglutination test and enzymelinked immunosorbent assay", Korean J Parasitol, 30, pp.83~90 (1992)
- Casciotti L, "CD8+ T-cell immunity against Toxoplasma gondii can be induced but not maintained in mice lacking conventional CD4+ T cells", Infect Immun, 70, pp.434~443 (2002)
- Guiton R, "Major role for CD8+ T cells in the protection against Toxoplasma gondii following dendritic cell vaccination", Parasite Immunol, 31, pp.631~640 (2009)
- Scharton-Kersten TM, "In the absence of endogenous IFN-g, mice develop unimpaired IL-12 responses to Toxoplasma gondii while failing to control acute infection", J Immunol, 157, pp.4045~4054 (1996)
- Charles E, "CD4 T-cell suppression by cells from Toxoplasma gondiiinfected retinas is mediated by surface protein PD-L1", Infect Immun, 78, pp.3484~3492 (2010)