應用活體多光子顯微術研究在老鼠小腸上敗血性的細胞剝落機制

Abstract

敗血病是很嚴重的細菌感染疾病，致死率甚至高達50%。然而人們對敗血病的起因與感染機制卻仍然不了解。除了傳統的生化分析，活體的動態觀察可更直接了解敗血病中細胞的不正常現象。我的實驗主要是利用多光子顯微鏡技術建立一套動態影像觀察的方法來研究小鼠腸上絨毛因為敗血病造成的嚴重細胞掉落機制。另一方面臨床上嚴重外傷或是敗血症會造成腸道通透性改變並產生屏障障礙，細胞掉落產生的空洞是否與屏障和通透性有關是值得研究的課題。 在我的研究中，我將老鼠分成控制組、敗血病組、嚴重敗血病組來觀察空洞與細胞掉落的狀況。首先我們發現在三組中有兩種不同的空洞類型，分別是完全無法通透的空洞與有機會通透的空洞，而在嚴重敗血病組有機會通透的空洞占的比例較高。而在嚴重敗血病組中空洞的比例比敗血病組和控制組多，接著我們隨著時間去量測不同組的細胞數目變化情形，我們發現控制組的細胞數量雖有起伏但維持著穩定的動態平衡，因為些許細胞補上空洞，敗血病組細胞數以緩慢的速度減少，並且在嚴重敗血病組的細胞數少得較快。

Epithelium of the small intestine, a mono discontinuous layer which consists of many epithelial cells but few gaps, plays a critical role in supporting gut barrier function. These epithelial cells function by migrating and shedding, that is, cells are shed from villi and create gaps. Cell shedding and migration are closely related to the defect of barrier function. However, the connection between abnormality of cell shedding and serious disease such as sepsis is not clear. This study used multi-photon microscopy to understand the mechanism of septic cell shedding in vivo. We constructed a sepsis model by lipopolysaccharide (LPS) and a dangerous sepsis model by LPS puls burn. Finally, the motion of cell shedding and migration was directly observed and detail was completely presented. We found in normal model cells formed dynamic equilibrium of shedding and production. However, in dangerous sepsis model epithelium presented intense shedding and increased permeability.