本文選題：田鼠巴貝斯蟲　切入點：免疫系統(tǒng)　出處：《甘肅農(nóng)業(yè)大學(xué)》2015年碩士論文　論文類型：學(xué)位論文

【摘要】：田鼠巴貝斯蟲(Babesia microti)是引發(fā)人與嚙齒動物巴貝斯蟲病最主要的病原體,它是頂復(fù)門、梨形蟲目、巴貝斯科、巴貝斯屬的一種寄生于宿主紅細胞內(nèi)的血液原蟲,主要經(jīng)過硬蜱叮咬、輸血或者血液制品等途徑感染及傳播,免疫力低的人或動物感染后表現(xiàn)出嚴重的臨床癥狀,甚至導(dǎo)致死亡,一般宿主則多為隱性感染,成為傳播來源。目前主要在美洲流行,近年來發(fā)病病例激增,同時在歐洲、亞洲等地方不斷發(fā)現(xiàn)感染病例,在我國,已有人感染田鼠巴貝斯蟲的報道,這一新發(fā)人獸共患病已經(jīng)給畜牧業(yè)和人類健康帶來了威脅。田鼠巴貝斯蟲感染宿主后多數(shù)處于隱性感染狀態(tài),在宿主體內(nèi)的增殖、分布和致病能力均研究較少,宿主的免疫反應(yīng)以及是否會對其它病原體的再感染造成影響等方面都沒有一個明確的研究結(jié)論。為此,本研究通過小鼠人工感染田鼠巴貝斯蟲模型,調(diào)查隱性感染過程中蟲體在宿主體內(nèi)的增殖、組織器官分布和對宿主血液凝固的影響,同時對宿主的免疫反應(yīng)以及與其他原蟲共感染關(guān)系進行研究。通過對田鼠巴貝斯蟲感染宿主后的熒光定量檢測,結(jié)果表明田鼠巴貝斯蟲可以在宿主體內(nèi)長期存在且感染后期依然保持較高數(shù)量的蟲體,同時在宿主的主要臟器組織均有分布。對感染后宿主凝血系統(tǒng)的研究表明田鼠巴貝斯蟲可以通過影響內(nèi)源性凝血系統(tǒng)使凝血時間縮短,這很容易引起一些血栓性疾病�？贵w水平檢測結(jié)果顯示,在田鼠巴貝斯蟲感染宿主后,抗體持續(xù)存在且處于一個較高的水平。通過流式細胞術(shù)對田鼠巴貝斯蟲不同感染階段T淋巴細胞亞群分化情況以及免疫細胞因子分泌水平做以研究,結(jié)果表明CD4+T細胞在控制田鼠巴貝斯蟲的感染過程中發(fā)揮了重要作用,并且在感染前期,由Th1型免疫細胞介導(dǎo)的細胞免疫發(fā)揮了主導(dǎo)作用,感染后期則以體液免疫為主。通過對正常小鼠和脾臟摘除小鼠在田鼠巴貝斯蟲感染后蟲體增殖規(guī)律、血液生理指標、血清細胞因子分泌水平等多方面做了比較研究,結(jié)果表明對于脾臟摘除小鼠,田鼠巴貝斯蟲可以引起更嚴重的感染,并且對其免疫系統(tǒng)和凝血系統(tǒng)產(chǎn)生更嚴重的影響,驗證了免疫缺陷宿主的感染嚴重性。分別選取弓形蟲(Toxoplasma gondii)和伊氏錐蟲(Trypanosoma evansi)與田鼠巴貝斯蟲構(gòu)建人工共感染模型,結(jié)果表明田鼠巴貝斯蟲感染后,可以顯著的加重弓形蟲的再感染,而對伊氏錐蟲的再感染沒有明顯的影響。本研究對田鼠巴貝斯蟲隱性感染和共感染的研究,將為其感染、傳播、免疫以及致病機制等方面的研究開辟新的思路,為這一新發(fā)傳染病的防控提供基礎(chǔ)。
[Abstract]:The most common pathogen causing human and rodent Babes's disease is a haemoprotozoa of the genus Pheloptera, Pyriformes, Babesco, Babes, which is parasitic on the red blood cells of the host, mainly by ticks. Blood transfusions or blood products are transmitted by other means. People or animals with low immunity show serious clinical symptoms after infection, and even cause death. Most hosts are recessive infections and become sources of transmission. At present, they are mainly prevalent in the Americas. In recent years, there has been a sharp increase in the number of cases, and infections have been continuously found in Europe, Asia and other places. In China, there have been reports of people infected with Babes's vole. This new zoonosis has posed a threat to animal husbandry and human health. There is no clear conclusion about the host's immune response and whether it will affect the reinfection of other pathogens. To investigate the effects of insect body proliferation, tissue and organ distribution and blood coagulation on the host during recessive infection. At the same time, the immune response and co-infection with other protozoa were studied. The results showed that Babes could exist in the host for a long time and still maintain a high number of parasites in the later stage of infection. At the same time, the main organs of the host were all distributed. Studies on the coagulation system of the host after infection showed that Babes could shorten the coagulation time by affecting the endogenous coagulation system. It is easy to cause some thrombotic diseases. Antibody levels test results show that after the vole Babes infection host, The differentiation of T lymphocyte subsets and the secretion of immune cytokines were studied by flow cytometry in different infection stages of Babes's worm in voles. The results showed that CD4 T cells played an important role in the control of Babes's infection in voles, and the cellular immunity mediated by Th1 type immune cells played a leading role in the early stage of infection. In the later stage of infection, humoral immunity was the main factor. The rules of body proliferation, blood physiological index, serum cytokine secretion level and so on were compared between normal mice and spleen excised mice after the infection of Babes worm in voles. The results showed that Babes of vole could cause more serious infection and had a more serious effect on immune system and blood coagulation system in splenectomy mice. The infection severity of the immunodeficient host was verified. Toxoplasma gondii and Trypanosoma evansii) were selected to construct an artificial co-infection model with Babes's vole. The results showed that the infected mice were infected with Babes, and the results showed that the infected mice were infected with Toxoplasma gondii and Trypanosoma evansii. Toxoplasma gondii reinfection can be significantly aggravated, but there is no obvious effect on the reinfection of Trypanosoma evansi. In this study, the recessive infection and coinfection of Babes parasite in voles will be infected and transmitted. The study of immune and pathogenic mechanism provides a basis for the prevention and control of this new infectious disease.
【學(xué)位授予單位】：甘肅農(nóng)業(yè)大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2015
【分類號】：S855.9

【參考文獻】

相關(guān)碩士學(xué)位論文 前1條

1 黃艷麗;Babesia microti截短性分泌抗原表達及兩種蜱傳病流行病學(xué)調(diào)查[D];甘肅農(nóng)業(yè)大學(xué);2013年

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本文編號：1649009