Induction mechanisms of mucosal immune response in intramucosal parasitic protozoan infection

粘膜内寄生原虫感染粘膜免疫反应的诱导机制

• 批准号: 12460136
• 负责人: OMATA Yoshitaka
• 金额: $ 8.96万
• 依托单位: OBIHIRO UNIVERSITY OF AGRICULTURE AND VETERINARY MEDICINE
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2000
• 资助国家: 日本
• 起止时间: 2000 至 2002
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-12460136/
• 关键词: Infection; Mucosal immunity; Defense mechanism; Immune response; Cryptosporidium parvum; Eimeria stiedai; Toxoplasma gondii; Neospora caninum

This study was aimed to clarify induction mechanism of mucosal immune responses in tissues invaded by parasitic protozoa and relationship between systemic immune responses and cell mediated immune responses. In addition, specific antigen molecules derived from the parasites were also attempted to analyze the immunologic and biological characteristics.Analysis of characteristics of Cryptosporidium parvum soluble antigenSoluble antigen was detected in the supernatant of feces of calves infected with C. parvum. The infected calves produced IgA antibody against the copro-antigen during convalescent phase of the infection.Analysis of feline enteroepithelial stages antigens in Toxoplasma gondiiFrom enteroepithelia stage parasites of T. gondii, cDNA library was constructed and 14 clones were isolated by immunoscreening. Sequence analysis and function assay showed similarity to 14-3-3 protein.Characteristics of Eimeria stiedai soluble antigen and immune responses in rabbits either infected or immunized with the antigenSoluble antigen was detected in the bile of infected rabbits. Rabbits infected with E. stiedai produced antibody to the antigen. Rabbits immunized with the soluble antigen showed resistant to the infection.Pathogenicity of Neospora caninum isolated from sheep and immune responses to the infection in miceNeospora caninum was isolated from sheep and the pathogenicity was examined by experimental infection in mice. Immunodeficient mice showed clinical signs to die. Immunocompetent mice showed without any clinical signs and produce antibody against the parasites.

本研究旨在阐明寄生原虫入侵组织后粘膜免疫应答的诱导机制以及系统免疫应答与细胞免疫应答的关系。此外，还尝试了从隐孢子虫中提取特异性抗原分子，分析其免疫学和生物学特性。微小隐孢子虫可溶性抗原特性分析小的感染犊牛在感染恢复期产生抗粪抗原的伊加抗体。猫肠上皮期弓形虫抗原分析构建了弓形虫cDNA文库，免疫筛选得到14个克隆。序列分析和功能分析表明，该蛋白与14-3-3蛋白相似，并具有斯氏艾美耳球虫可溶性抗原的特性和免疫兔的免疫应答。感染E. stiedai产生了针对该抗原的抗体。用可溶性抗原免疫家兔，结果表明，家兔对犬新孢子虫感染有一定的抵抗力。从绵羊分离的犬新孢子虫的致病性及对小鼠感染的免疫反应免疫缺陷小鼠表现出死亡的临床体征。免疫活性小鼠无任何临床症状，并产生抗寄生虫的抗体。

项目成果

T.Koyama, et al.: "A 14-3-3 protein homologouue is expressed in feline enteroepithelial-stages of Toxoplasma gondii"Veterinary Paarsitology. 96. 65-74 (2001)

T.Koyama 等人：“14-3-3 蛋白同源物在弓形虫的猫肠上皮阶段表达”《兽医寄生虫学》。

S.Hanada, et al.: "Relationship between liver disorders and protection against Eimeria stiedai Infection in rabbits immunized with soluble antigens from the bile of infected rabbits"Veterinary Parasitology. 111. 261-266 (2003)

S.Hanada 等人：“用受感染兔子胆汁中的可溶性抗原进行免疫的兔子中，肝脏疾病与预防艾美耳球虫感染之间的关系”《兽医寄生虫学》。

T. Koyama, et al.: "Antigens expressed in feline enteroepithelial-stages parasites of Toxoplasma gondii"Journal of Veterinary Medical Sciences. 62. 1089-1092 (2000)

T. Koyama 等人：“弓形虫猫肠上皮期寄生虫中表达的抗原”《兽医医学科学杂志》。

Y.Kobayashi, et al.: "Naturally-occurring Neospora caninum infection in an adult sheep and her twin fetuses"Journal of Parasitology. 87(2). 434-436 (2001)

Y.Kobayashi 等人：“成年羊及其双胞胎胎儿中自然发生的犬新孢子虫感染”寄生虫学杂志。

Y.Omata, et al.: "Identification and the role of soluble antigens detected in bile from Eimeria stiedai-infected rabbits"Journal of Parasitology. 87(2). 287-291 (2001)

Y.Omata 等人：“在感染斯氏艾美耳球虫的兔子胆汁中检测到的可溶性抗原的鉴定和作用”寄生虫学杂志。