Type1 Transglutaminase and the Differentiation of Corneal Epithelium

1型转谷氨酰胺酶与角膜上皮的分化

• 批准号: 08672020
• 负责人: OHASHI Yuichi
• 金额: $ 1.34万
• 依托单位: Ehime University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1996
• 资助国家: 日本
• 起止时间: 1996 至 1997
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-08672020/
• 关键词: corneal epithelium; ocular surface; keratinization; transglutaminase; vitamin A; differentiation; RT-PCR; Western-blotting; cornifin; 免疫組織染色

The corneal epithelium continueously proliferates and properly differentiates in order to maintain its transparency. To clarify the process of corneal epithelial differentiation, we attempted to analyze the expression of the transglutaminase (TG), one of the enzymes which regulate keratinization, in the human corneal and conjunctival epithelium. The expression of mRNA for the TG was demonstrated by reverse transcription-polymerase chain reaction (RT-PCR). Subsequent immunohistochemical study has revealed the presence of the cornifin, a substrate for the TG,in the corneal and conjunctival epithelium as well.In the next study, we monitored the chronological change of the TG in the corneal epithelium of the rats which were fad with vitamin A-deficient diet. Superficial punctate keratopathy appeared together with decreased lacrimation at 9 weeks after initiating the regimen, progressing to filamentary keratitis by week 12. Finally, the lesion simulating keratomalacia developed at Week 18.The seniquatative RT-PCR has demonstrated that the expression of type 1 TG was increased well in accordance with the duration of the treatment, while that of type 2 TG was gradually decreased.In another study, we obtained hyperimmune sera from the rabbit which had been immunized with the recombinant TG protain. Immunohistochemical studies using this particular antibody has demonstrated the presence of TG in the corneal amd conjunctival epithelium of the rats and humans. The staining was found to be intense especially at the cell membrane.These result strongly indicated that TG is involved in the keratinization process of corneal and conjunctival epithelium, shedding an insight to search for a new substance which is able to control the differentiation of ocular surface eipthelia.

角膜上皮不断增殖和适当分化，以保持其透明度。为了阐明角膜上皮细胞分化的过程，我们试图分析调节角质化的酶之一转谷氨酰胺酶(Tg)在人角膜和结膜上皮中的表达。逆转录-聚合酶链式反应(RT-PCR)检测TGmRNA的表达。随后的免疫组织化学研究发现，角膜和结膜上皮中也存在甘油三酯的底物--角蛋白。在下一项研究中，我们监测了缺乏维生素A饮食的大鼠角膜上皮中甘油三酯的时间变化。用药后9周出现浅层点状角膜病变，12周发展为丝状角膜炎，18周出现类似角膜软化的病变。逆转录聚合酶链式反应显示，1型TG的表达随着治疗时间的延长而增加，而2型TG的表达则逐渐降低。用这种特殊抗体进行的免疫组织化学研究表明，TG存在于大鼠和人的角膜和结膜上皮中。结果表明，TG参与了角膜和结膜上皮的角化过程，为寻找控制眼表上皮细胞分化的新物质提供了线索。

项目成果

俊野敦子 他: "プロスタグランディンF2αイソプロピルウノプロストン点眼薬による角膜上皮障害の発症メカニズム" 日本眼科学会雑誌. 102・2. 101-105 (1998)

Atsuko Toshino等：“前列腺素F2α异丙基乌诺前列酮滴眼液引起的角膜上皮损伤的发生机制”日本眼科学会杂志102・2（1998）。

俊野 敦子 他: "プロスタグランディンF2αイソプロピルウノプロストン点眼薬による角膜上皮障害の発症メカニズム" 日本眼科学会雑誌. 102・2. 101-105 (1998)

Atsuko Toshino等：“前列腺素F2α异丙基乌诺前列酮滴眼液引起的角膜上皮损伤的发生机制”日本眼科协会杂志102・2（1998）。

A.Toshino, et al: "The Mechanism of Corneal Epithelial Disorder Induced by Prostaglandin F2 alpha Isopropyl Unoprostone" Soc Ophthalmol Jpn. 102-2. 101-105 (1998)

A.Toshino 等人：“前列腺素 F2 α 异丙基乌诺前列酮诱发的角膜上皮疾病的机制”Soc Ophasemol Jpn。