Induction of Protective Immunity by hsp70 Derived from Intracellular Parasites

细胞内寄生虫 hsp70 诱导保护性免疫

• 批准号: 09670265
• 负责人: YUI Katsuyuki
• 金额: $ 2.05万
• 依托单位: Nagasaki University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1997
• 资助国家: 日本
• 起止时间: 1997 至 1998
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-09670265/
• 关键词: Intracellular Parasites; Toxoplasma gondii; Stress Protein; hsp70; Protective immunity; Cytotoxic T Lymphocytes; hsp 70; トキソプラズマ; 原虫; 寄生; 分子生物学; 抗体

(1) We have cloned a full-length cDNA of Toxoplasma hsp7O and produced its recombinant protein as well as monoclonal antibodies against it. Using these reagents, we identified two hsp7O-like protein expressed in T.gondii. Mice orally infected with T.gondii showed significant antibody responses against T.gondii hsp7O during acute phase but not during chronic phase of infection. Immunization of mice with purified T.gondii hsp7O conferred protective immunity against challenge infection with T.goiidii. The protective effect was more significant in mice immunized with hsp7O purified from T.gondii than those immunized with recombinant hsp7O, suggesting that hsp7O-associated molecule may play a role in inducing the protective immunity.(2) The effect of CD8 cytotoxic T lymphocyte (CTL)-mediated lysis of host cells on the viability of intracellular T.gondii was investigated. Quantitative competitive PCR of the gene encoding T.gondii major surface antigen (SAG-1) was combined with treatment of the parasites with DNase, which removed the DNA template of non-viable parasites. The induction by CD8 CTL of apoptosis in cells infected with T.gondii did not result in the reduction of live parasites, indicating that intracellular T.gondii remains alive after lysis of host cells by CTL.

(1)克隆了弓形虫hsp70全长cDNA，制备了重组蛋白和单克隆抗体。利用这些试剂，我们鉴定了两个在弓形虫中表达的hsp70样蛋白。经口感染弓形虫的小鼠在急性期对弓形虫hsp70有明显的抗体反应，而在慢性感染期无明显抗体反应。用纯化的弓形虫hsp70免疫小鼠对goiidii的攻击感染具有保护性免疫。弓形虫纯化hsp70免疫小鼠的保护作用比重组hsp70免疫小鼠的保护作用更显著，提示hsp70相关分子可能在诱导保护性免疫中起作用。(2)研究了CD8细胞毒性T淋巴细胞（CTL）介导的宿主细胞裂解对细胞内弓形虫生存能力的影响。将弓形虫主表面抗原（SAG-1）编码基因的定量竞争PCR与DNA酶处理相结合，去除非活虫的DNA模板。在感染弓形虫的细胞中，CD8 CTL诱导细胞凋亡并没有导致活寄生虫的减少，这表明细胞内弓形虫在CTL裂解宿主细胞后仍然存活。

项目成果

K.Yamashita, K.Yui, M.Ueda, and A.Yano: "Cytotoxic-T Lymphocyte-Mediated Lysis of Toxoplasma gondii-Infected Target Cells Dose Not Lead to Death of Intracellular Parasites." Infection & Immunity. 66. 4651-4655 (1998)

K.Yamashita、K.Yui、M.Ueda 和 A.Yano：“细胞毒性 T 淋巴细胞介导的弓形虫感染靶细胞裂解不会导致细胞内寄生虫死亡。”

K.Yamashita et.al.: "Cyfofoxic-T-lymphocyte-mediated lysis of Toxoplasma gondii-infected target cells does not lead to death of intracellular parasites" Infection and Immunity. 66・10. 4651-4655 (1998)

K. Yamashita 等人：“Cyfoxic-T 淋巴细胞介导的弓形虫感染的靶细胞内裂解不会导致细胞寄生虫死亡”感染和免疫 66·10 (1998)。

K.Yui and A.Yano: "Humoral immune responses against members of the hsp70 family in Toxoplasma gondii" Japanese Journal of Tropicel Medicine and Hygine. 26・4. 305-318 (1998)

K.Yui 和 A.Yano：“针对弓形虫 hsp70 家族成员的体液免疫反应”，《日本热带医学与卫生杂志》26・4（1998 年）。

K.Yui and A.Yano: "Humoral immune responses against members of the hsp70 family in Toxoplasma gondii" Japanese Journal of Tropical Medicine and Hygine. 26・4. 305-318 (1998)

K.Yui 和 A.Yano：“针对弓形虫 hsp70 家族成员的体液免疫反应”，《日本热带医学与卫生杂志》26・4（1998 年）。

K.Yui and A.Yano: "Humoral Immune Reponses against Members of the hsp70 in Toxoplasma gondii" Japanese journal of Tropical Medicine and Hygiene. 26. 305-318 (1998)

K.Yui 和 A.Yano：“针对弓形虫中 hsp70 成员的体液免疫反应”日本热带医学与卫生杂志。