Use of bovine-RBC-substituted SCID mice for the studies of Babesia parasites

使用牛 RBC 替代 SCID 小鼠研究巴贝虫寄生虫

• 批准号: 07456146
• 负责人: TSUJI Masayoshi
• 金额: $ 4.16万
• 依托单位: Rakuro-gakuen University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 1995
• 资助国家: 日本
• 起止时间: 1995 至 1997
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-07456146/
• 关键词: SCID mice; Animal model; Babesia ovata; Babesia bovis; Cerebral babesiosis; Antigenic variation; Babesia

Various experimental systems were developed for the studies of Babesia parasites using bovine-red blood cell-substituted (Bo-RBC-SCID mice), and following results were obtained(1) Isolation of a new Babesia parasite : Using Bo-RBC-SCID mice, a new bovine Babesia parasite (Oshima strain) were isolated from grazing cattle in Hokkaido, Japan. The isolate differed from Miyake strain, which is the type strain of Babesia ovata, in terms of morphology, antigenic structure and genomic DNA,but shared the same vector tick, Haemaphysalis longicornis. Thus, Babesia ovata oshimensis n. var. has been proposed. Bo-RBC-SCID mice infected with Babesia parasites showed various clinical symptoms, including hemoglobinuria, jaundice and nerve symptoms, and therefore may serve as a useful model system for studying the mechanisms of disease caused by Babesia parasites.(2) Persistent infection and antigenic variation of Babesia : Epidemiological survey with parasite isolation using Bo-RBC-SCID mice revealed t … More hat Babesia parasites persistently infect cattle in Okushiri island, Hokkaido. Significant variations in antigenic profiles and genomic DNA were observed among the samples obtained at different time points from a single infected animal, implicating possible antigenic variations. Monoclonal antibodies against B.ovata Oshima strain has been made, and a clone, 1A2, which produces antibody inhibitory to the parasite growth in Bo-RBC-SCID mice was selected. The 1A2 antibody was found to recognize a 56-kDa merozoite surface protein (P56) which may potentially be involved in antigenic variation. The cDNA clone encoding P56 was obtained, sequenced, and expressed in E.coli.(3) A mouse model for cerebral babesiosis : Bo-RBC-SCID mice infected with Babesia bovis were found to display central nerve symptoms. Light microscopy revealed sequestration of parasitized RBC in the microvessels in the brain of SCID mice. Electron microscopy showed the presence of "knob" like conical projections on the surface of infected RBCs, with which the parasitized RBCs appeared to adhere to the capillary endothelium in SCID mice brain. Those findings are strikingly similar to those found in bovine cerebral babesiosis and also in human cerebral malaria, and therefore B.bovis-infection in Bo-RBC-SCID mice can be used as a model for those disease. Less

利用牛红细胞替代的（Bo-RBC-SCID小鼠）建立了各种实验系统以研究巴氏疟原虫，并获得了以下结果：（1）分离一种新的巴氏疟原虫：利用Bo-RBC-SCID小鼠，从日本北海道放牧牛中分离出一种新的牛巴氏疟原虫（大岛株）。该分离物与卵形Babyelovata的模式株Miyake株在形态、抗原结构和基因组DNA上存在差异，但与长角血蜱（Haemaphysalis longicornis）具有相同的媒介蜱种。Oshimensis n.变种已经被提议了。Bo-RBC-SCID小鼠感染巴贝虫后表现出多种临床症状，包括血红蛋白尿、黄疸和神经症状，可作为研究巴贝虫致病机制的模型系统。(2)巴氏疟原虫的持续感染和抗原变异：使用Bo-RBC-SCID小鼠分离寄生虫的流行病学调查显示， ...更多信息 在北海道奥尻岛，牛持续感染巴氏疟原虫。在不同时间点从单个感染动物获得的样品中观察到抗原谱和基因组DNA的显著变化，暗示可能的抗原变异。制备了卵圆线虫Oshima株的单克隆抗体，并筛选出一个能产生抗卵圆线虫生长抗体的克隆1A2。发现1A2抗体识别56-kDa裂殖子表面蛋白（P56），其可能潜在地参与抗原变异。获得编码P56的cDNA克隆，测序，并在大肠杆菌中表达。(3)脑巴贝斯虫病的小鼠模型：发现感染牛巴贝斯虫的Bo-RBC-SCID小鼠显示中枢神经症状。光学显微镜观察发现，SCID小鼠脑内的微血管中存在寄生红细胞。电子显微镜观察发现，被寄生的红细胞表面出现"球形"的圆锥状突起，并粘附在SCID小鼠脑毛细血管内皮细胞上。这些发现与牛脑巴贝斯虫病和人脑疟疾中发现的那些惊人地相似，因此Bo-RBC-SCID小鼠中的牛B. bovis感染可用作这些疾病的模型。少

项目成果

Ishihara C., Hiratai R., Tsuji M., Yagi K., Nose M.and Azuma I.: "Mannan decelerate the clearance of human red blood cells in SCID mouse." Immunopharmacology. 38. 223-228 (1998)

Ishihara C.、Hiratai R.、Tsuji M.、Yagi K.、Nose M.和 Azuma I.：“甘露聚糖可减缓 SCID 小鼠中人类红细胞的清除。”

辻 正義、新井 智、金 三柱、萩原 克郎、石原 智明: "ヒトとマラリアのモデル-赤血球置き換えSCIDマウスを用いた住血原虫症の研究-" 日本疾患モデル学会. 13. 29-35 (1997)

Masayoshi Tsuji、Satoshi Arai、Samju Kim、Katsuro Hagiwara、Tomoaki Ishihara：“人类和疟疾模型 - 使用红细胞替代 SCID 小鼠研究血吸虫病”日本疾病模型学会 13. 29-35 (1997)。

Ishihara C., Shimakawa S., Tusuji M., Arikawa J., and Tokura S.: "A sulfated chitin, SCM-chitin III, inhibits the clearance of human erythrocytes from the blood circulation in the erythrocyte-transfused SCID mice" Immunopharmacology. 29. 65-71 (1995)

Ishihara C.、Shimakawa S.、Tusuji M.、Arikawa J. 和 Tokura S.：“硫酸化几丁质，SCM-几丁质 III，抑制红细胞输注 SCID 小鼠血液循环中人红细胞的清除”

Ohta M., Kawazu S., Terada Y., Kamio T., Tsuji M., and Fujisaki K.: "Experimental transmission of Babesia ovata oshimensis n. var. of cattle in Japan by Haemaphysalis longicornis." J.Vet. Med. Sci.58. 1153-1155 (1996)

Ohta M.、Kawazu S.、Terada Y.、Kamio T.、Tsuji M. 和 Fujisaki K.：“通过长角血蜱在日本牛中进行的巴贝斯虫 ovata oshimensis n. var. 的实验传播。”

Tsuji M., Fujioka S., Arai S., Tanayama H., Ishihara C., and Aikawa M.: "A mouse model for cerebral babesiosis" Parasitol. Today. 12. 203-205 (1996)

Tsuji M.、Fujioka S.、Arai S.、Tanayama H.、Ishihara C. 和 Aikawa M.：“脑巴贝西虫病小鼠模型”Parasitol。