枯西錐蟲(Trypanosoma cruzi)引起卡格氏病(Chagas’ disease)的致病機轉包括由錐蟲侵犯或蟲體釋出物質造成宿主之心臟或腸胃等器官的組織損傷，但在慢性感染期血液及組織中不易發現蟲體。小鼠感染Trypanosoma musculi後在慢性期的周邊血液中雖偵測不到蟲體，但卻常出現在腎臟的直血管(vasa recta)中，形成一個獨特的腎臟型蟲體（kidney form, KF）。本研究以BALB/c小鼠為實驗動物，探討在枯西錐蟲感染之動物模式中，宿主體內是否有腎臟型蟲體存在。分別在感染後20、40、60、80天做小鼠腎臟組織切片，以20及40天為急性期，與60天及以上的慢性期作比較；急性期與慢性期均有明顯的組織病變且均發現無鞭型蟲體（amastigote），證明在慢性期時，枯西錐蟲仍可能以無鞭型蟲體繼續存在於腎臟中。以感染不同天數之小鼠腎臟組織與枯西錐蟲無鞭型蟲體為抗原，分別對感染20、40、60、80、100、300天之小鼠血清進行酵素免疫分析，結果發現不同感染期的腎臟組織抗原對感染40天的血清都呈現較高的效價，顯示小鼠在急性感染時的血清對腎臟組織有較強的辨識能力；抗無鞭型蟲體抗原的血清效價隨感染天數持續上升，此結果是否與慢性期蟲體仍能存活於組織中持續釋放抗原相關，有待進一步研究證實。在西方墨點分析方面，以rat anti-epimastigote血清來分析感染與未感染小鼠之腎臟組織抗原，發現感染與未感染之小鼠腎臟皆有一32 kDa抗原可被辨識，感染小鼠之腎臟另有27及49 kDa 抗原可被辨識；以rat anti-amastigote血清分析感染與未感染小鼠之腎臟組織抗原，發現感染與未感染之小鼠腎臟皆有28及48 kDa抗原可被辨識，血清辨識感染之腎臟抗原強度以感染40天的腎臟抗原辨識力最強，推測或許與急性感染時腎臟組織中amastigote蟲體大量增生有關，至於這些抗原在腎臟組織感染過程中扮演的角色為何，需進一步研究分析。

Chagas’ disease induced by Trypanosoma cruzi infection causes damages in heart and digestive tract of the host, but trypanosomes were rarely found in blood and tissue during chronic infection. Although trypanosomes could not be found in the peripheral blood of Trypanosoma musculi infected mice during chronic stage, trypanosomes detected in vasa recta of kidney became a unique kidney form (KF). In this investigation, BALB/c mouse was used as animal model to examine if kidney form of T. cruzi exists in chronic stage. Kidney sections were made on the 20, 40, 60, and 80th day after infection of each mouse with 1,000 bloodstream trypanosomes. In order to compare with chronic stage, kidney sections obtained from mice 20 and 40 days after infection were regarded as acute phase. Amastigotes of T. cruzi as well as significant tissue damages were found in both acute and chronic stages. The results indicated that T. cruzi may exist in amastigote form in mouse kidney during chronic infection. ELISA was employed to measure mouse serum specific antibody titers which recognize mouse kidney antigen infected with trypanosomes 20 to 300 days respectively. Peak titer was observed on the 40th day of infection. Results showed that the ability of acute serum recognizing infected kidney antigen was better than chronic serum. On the other hand, antibody titers that recognize amastigote antigens increased gradually during the infection. It seems correlated with trypanosomes existing and releasing antigen during chronic infection. Antisera from rat immunized with epimastigote or amastigote could recognize infected and normal mouse kidney antigen. Anti-epimastigote sera detected 27 and 49 kDa proteins and anti-amamastigote sera detected 28 and 48 kDa proteins of infected mouse kidney antigen. Functions of these molecules are still not clear and require further characterization in the future.

摘要……………………………………………………………………….I
英文摘要………………………………………………………………...II
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圖表目錄………………………………………………………………..IV
前言………………………………………………………………………1
材料與方法………………………………………………………………4
結果……………………………………………………………………..15
討論……………………………………………………………………..19
參考文獻………………………………………………………………..23
圖表……………………………………………………………………..26
附錄……………………………………………………………………..53

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