Soluble Fas Ligand and Ocular Immune Privilege

可溶性 Fas 配体与眼部免疫特权

• 批准号: 6857036
• 负责人: MEREDITH GREGORY-KSANDER
• 金额: $ 41.7万
• 依托单位: SCHEPENS EYE RESEARCH INSTITUTE
• 依托单位国家: 美国
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-12-01 至 2009-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6857036
• 关键词: CD95 molecule; cell line; extracellular matrix; eye; gene expression; genetic strain; genetically modified animals; glycosylation; immunoregulation; intermolecular interaction; laboratory mouse; macrophage; mass spectrometry; neuroimmunomodulation; neuroregulation; neutrophil; posttranslational modifications; protein localization; protein structure function; proteolysis

DESCRIPTION (provided by applicant): Fas ligand (FasL) is produced as a membrane-bound and soluble protein and both forms are expressed within the immune privileged eye. In our previous studies we used an ocular tumor model to demonstrate that the different forms of FasL regulate innate immunity in the eye: (i) membrane FasL (mFasL) induces inflammation and terminates immune privilege, while (ii) soluble FasL (sFasL) prevents inflammation and maintains immune privilege. Therefore, given that FasL is constitutively expressed within the eye, and the membrane form of FasL is pro-inflammatory, we propose that in a normal eye either: (i) the pro-inflammatory function of mFasL is blocked, and/or (ii) FasL is expressed primarily in the soluble (anti-inflammatory) form. Our experimental data support the latter. Western blot analysis of FasL was performed on normal, FasL knockout, and chronically inflamed eyes. A high ratio of soluble (27 kDa) to membrane (38 kDa) FasL (10:1) was detected in normal eyes. Three additional bands (28-31 kDa) of modified sFasL were detected that were completely absent in the eyes of FasL knockout mice. The modified sFasL was unique to the eye and not found in other immune privileged sites, such as the testis. Finally, the 27kD and 31kD sFasL bands were completely absent from eyes that lacked immune privilege and displayed chronic inflammation secondary to pigment dispersion syndrome. We hypothesize that modified sFasL is expressed within the eye and plays a central role in maintaining immune privilege. This hypothesis will be tested in three Specific Aims (i) determine where sFasL is expressed in the eye and how it is modified, (ii) determine how modified sFasL stimulates innate immunity, and (iii) determine if modified sFasL controls immune privilege. We believe this study will advance not only our understanding of immune privilege, but help explain the controversy over the physiological role of FasL in transplants and tumors.

描述（由申请人提供）：FAS配体（FASL）作为膜结合和可溶性蛋白质产生，两种形式在免疫特权的眼中表达。在我们先前的研究中，我们使用眼部肿瘤模型来证明，FASL的不同形式调节眼睛中的先天免疫：（i）膜FASL（MFASL）诱导炎症并终止免疫特权，而（II）可溶性FASL（SFASL）阻止了炎症和维持免疫自由。因此，鉴于FASL在眼睛内部组成型表达，而FASL的膜形式是促炎性的，我们提出，在正常的眼睛中，要么提出：（i）MFASL的促炎功能被阻断，并且/或（II）FASL主要以可溶性（反激常）形式表达。我们的实验数据支持后者。 FASL的蛋白质印迹分析是在正常，FASL敲除和长期发炎的眼睛上进行的。在正常的眼睛中检测到可溶性（27 kDa）与膜（38 kDa）FASL（10：1）的高比例。检测到FASL敲除小鼠眼中完全不存在的另外三个带（28-31 kDa）的修饰SFASL。修改后的SFASL是眼睛独有的，在其他免疫特权部位（例如睾丸）中找不到。 最后，完全没有免疫特权并显示出继发于色素分散综合征的慢性炎症的眼睛完全没有眼睛。 我们假设修改后的SFASL在眼睛内表达，并在 保持免疫特权。该假设将在三个特定目的（i）中进行检验（i）确定SFASL在眼睛中表达的位置以及如何修饰，（ii）确定修饰的SFASL如何刺激先天免疫，（iii）确定修饰的SFASL控制是否对免疫特权进行了控制。我们认为，这项研究不仅会提高我们对免疫特权的理解，还可以帮助解释FASL在移植和肿瘤中生理作用的争议。