A novel mechanism on disposing of effete enterocytes

处理无效肠细胞的新机制

• 批准号: 05670003
• 负责人: IWANAGA Toshihiko
• 金额: $ 1.41万
• 依托单位: Niigata University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1993
• 资助国家: 日本
• 起止时间: 1993 至 1994
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-05670003/
• 关键词: Enterocytes; Apoptosis; Lymphocytes; Macrophages; 小腸; 腸管バリヤー; 上皮内リンパ球

1. Effete epithelial cells in the small intestine of the guinea pig, major parts of cell bodies, are phagocytosed by lamina propria macrophages. However, the apical cytoplasm remain within the epithe lium after the apoptotic event. The present study demonstrated that the skin-like apical cytoplasm is connected with adjacent enterocytes by junctional complexes, still keeping the epithelial barrier.2. The apical cytoplasm with the brush border is protruded into the luminal space due to closing of adjacent cells, and pinched off into the lumen when the adjacent cells contacted. During the process, no holes of the epithelium were recognizable. Thereafter, there were numerous cytoplasmic fragments with the brush border in the lumen of intestine.3. In the rat, the intestinal lumen contained numerous cell bodies of apoptotic enterocytes with nuclei, suggesting exfoliation of whole cell bodies into the lumen.4. The guines pig-type mechanism on disposing of effete epithelial cells was recognized in the monkey and horse, while the rat-type mechanism was shared by the mouse. Humans were basically classified into the latter type.5. Cell death of enterocytes may not be soley programd cell death, but easily induced by external factors. Intraepithelial lymphocytes are involved in the induction of apoptosis in the guinea pig, while in the rat lamina propria macrophages participate in this mechanism.

1.豚鼠小肠中的败血性上皮细胞是细胞体的主要部分，被固有层巨噬细胞吞噬。然而，在凋亡事件后，顶端细胞质仍保留在上皮细胞内。本研究表明，表皮样顶端细胞质通过连接复合物与相邻肠上皮细胞连接，仍保持上皮屏障.顶端的细胞质由于相邻细胞的封闭而突出到管腔内，并在相邻细胞接触时被夹断到管腔内。在此过程中，上皮细胞没有可识别的孔。此后，在细胞腔内可见大量刷状缘的胞质碎片.大鼠肠腔中含有大量凋亡的肠上皮细胞胞体，胞核完整，胞体脱落进入肠腔.在猴和马中识别出了豚鼠处理衰老上皮细胞的类型机制，而小鼠共享大鼠类型机制。人类基本上属于后一种。肠上皮细胞的死亡可能不是单纯的程序性细胞死亡，易受外界因素的诱导。上皮内淋巴细胞参与豚鼠细胞凋亡的诱导，而在大鼠固有层巨噬细胞参与这一机制。

项目成果

Han, H: "Species-differences in the process of apoptosis in epithelial cells of the small intestine : An ultrastructural and cytochemical study of luminal cell elements." Arch.Histol.Cytol.56. 83-90 (1993)

Han，H：“小肠上皮细胞凋亡过程中的物种差异：管腔细胞元件的超微结构和细胞化学研究。”

Iwanaga, H.: "Morphological analysis of acute ulcerative colitis experimentally induced by dextran sulfate sodium in the guinea pig : Some possible mechanism of cecal ulceration." J.Gastroenterol. 29. 430-438 (1994)

Iwanaga, H.：“用葡聚糖硫酸钠在豚鼠实验中诱导的急性溃疡性结肠炎的形态学分析：盲肠溃疡的一些可能机制。”

Iwanaga,T.: "Morphological analysis of acute ulcerative colitix experimentally induced by dextran sulfate sodium in the guinea pig:some possible mechanism of cecal ulceration." J.Gatroenterol.29. 430-438 (1994)

Iwanaga,T.：“用葡聚糖硫酸钠在豚鼠实验中诱导的急性溃疡性结肠炎的形态学分析：盲肠溃疡的一些可能机制。”

岩永敏彦: "腸上皮細胞の細胞孔(アポトーシス)に関わるマクロファージと上皮内リンパ球" 新潟医学会雑誌. 108. 167-172 (1994)

Toshihiko Iwanaga：“巨噬细胞和上皮内淋巴细胞参与肠上皮细胞的细胞孔（细胞凋亡）”Niigata Medical Society Journal 108. 167-172（1994）。

Iwanaga, T: "Macrophages phagocytosing enterocytes" Igakuno-Ayumi. 165. 457-460 (1993)

Iwanaga, T：“巨噬细胞吞噬肠上皮细胞” Igakuno-Ayumi。