Role of CD98 Glycoprotein in Intestinal Inflammation

CD98 糖蛋白在肠道炎症中的作用

• 批准号: 8424676
• 负责人: Hamed Laroui
• 金额: $ 10.01万
• 依托单位: GEORGIA STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-09-24 至 2017-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8424676
• 关键词: Adhesions; Advisory Committees; Alginates; Amino Acids; Animals; Anti-Inflammatory Agents; Anti-inflammatory; Antibiotics; Ants; Award; Bacteria; Bacterial Translocation; Binding; Biochemical; Biology; C-terminal; Cell Communication; Cell surface; Cells; Chemicals; Chitosan; Chronic; Colitis; Colon; Data; Development Plans; Digestive System Disorders; Disease; Down-Regulation; Encapsulated; Epithelial; Epithelial Cells; Event; Extracellular Domain; Functional disorder; Glycoproteins; Human; Hydrogels; Immune; Immunology; In Vitro; Inflammation; Inflammation Mediators; Inflammatory; Inflammatory Bowel Diseases; Inflammatory disease of the intestine; Interleukin-1; Interleukin-10; Intestines; Mentored Research Scientist Development Award; Mentors; Mentorship; Microbiology; Molecular; Molecular Biology; Mus; Nanotechnology; Neurofibromin 2; Non-Viral Vector; Pathogenesis; Permeability; Phosphorylation; Physiological; Play; Production; Research; Research Support; Resistance; Role; Serine Phosphorylation Site; Signal Transduction; Site; Small Interfering RNA; TNF gene; Tail; Techniques; Technology; Therapeutic; Training; Transgenic Mice; Universities; base; career development; computerized data processing; cytokine; extracellular; in vivo; interest; intestinal epithelium; nanoparticle; overexpression; professor; research and development; research study; symposium; therapeutic development; villin

DESCRIPTION (provided by applicant): CD98 plays an important role in coordinating intestinal epithelial events, such as adhesion/polarity, amino acid transport, and direct binding o cell surface molecules. The unique molecular orientation of CD98 with a PDZ-binding domain in the extracellular C-terminal tail suggests that extracellular signaling plays a role in its multipl functions. For example, ecto-phosphorylation of CD98 enhances heterotypic cell-cell interactions, and the extracellular domain possessing serine phosphorylation sites is crucial for this effect. CD98 expression is increased in inflammatory inflammation conditions, such as inflammatory bowel disease (IBD). Earlier research supports the ability of intestinal epithelial cell-specific CD98 to induce barrier dysfunction and stimulate the production of pro-inflammatory mediators. Studies by our group have collectively shown that CD98 expression plays a role in the pathogenesis of intestinal bowel disease (IBD) in humans. Our overall hypothesis is that colonic CD98 plays a critical role in initiating and perpetuating intestinal coltis. The initial aim of this proposal is to investigate the role of CD98/bacteria interactions in the los of intestinal barrier function. We will additionally focus on establishing the role of CD98 in spontaneous colitis. The efficacy of knockdown of CD98 expression in inflamed colon will subsequently be assessed using a targeted nanotechnology approach. The project will involve a variety of biochemical, chemical, nanotechnological, molecular, in vitro, and in vivo approaches. It is envisaged that the proposed experiments will facilitate identification of the molecular mechanisms underlying the functional role of CD98 in intestinal inflammation and allow the development of therapeutic strategies targeting intestinal inflammatory conditions, including IBD. My first aim will focus on investigating if intestinal epithelial CD98 and CD98/bacteria interactions participate in loss of intestinal barrier function. Preliminary data obtained by our group showed that overexpression of colonic CD98 increases intestinal permeability, bacterial translocation and expression of pro-inflammatory cytokines, such as IL-1¿ and TNF¿. Our initial aim is to investigate whether bacteria initiate intestinal barrier function in mice that specificaly overexpress colonic CD98. Specifically, Villin-CD98+/+ transgenic mice will be treated with antibiotic, and the intestinal barrier function and cytokine expression in these animals assessed in relation to untreated Villin-CD98+/+ transgenic mice. Secondly, direct interactions between CD98 and bacteria and their signaling processes will be investigated via ex and in vivo approaches. These experiments should clarify the sequential role of CD98 expression and CD98/bacteria interactions in loss of intestinal barrier function. Thus, my second aim will study the colonic CD98 expression effect on the modulation of colitis. We have demonstrated that DSS-induced colitis is aggravated in villin-CD98 transgenic mice (in which CD98 is expressed in colonocytes) than wild-type animals. In contrast, mice with low colonic CD98 expression (CD98fl/+Villin-Cre) are more resistant to DSS, compared to those with higher colonic CD98 expression (CD98fl/+). We propose to establish the role of CD98 expression in chronic colitis by assessing spontaneous inflammation in IL-10-/-/CD98fl/+Villin-Cre, IL-10-/-/Villin-CD98+/+ and IL-10-/-/CD98fl/+ animals. Finally, my third aim will investigate the site-directed delivery of ant-CD98 siRNA using non-viral vectors encapsulated in nanoparticles (NPs) as carriers effectively inhibits induced colitis. Recently, we described an original technique targeting the colon with anti-inflammatory molecules loaded in NPs and encapsulated in an alginate-chitosan hydrogel. Using this technology, we obtained preliminary data showing that TNF¿ siRNA-loaded NPs suppress intestinal inflammation. We further propose to specifically target and deliver CD98 siRNA to inflamed colonic (epithelial and immune) cells that overexpress CD98 in mice with induced colitis. PUBLIC HEALTH RELEVANCE: This is a Mentored Research Scientist Development Award application for Dr. Hamed Laroui, a biochemist, nanotechnologist, and physical chemist by training with specialization in Digestive Diseases. He has initiated an independent study from his mentor on the physiologic and biologic role of CD98, a glycoprotein that is a heterodimer in intestinal epithelium. He will be using this award opportunity to differentiate himself from his mentor by shifting his research interest from basic biology to potential therapeutic treatment based on CD98. His main hypothesis is that temporary downregulation of CD98 in the intestinal epithelium under pathological conditions modulates inflammation. As a new Assistant Professor at Georgia State University, Dr. Laroui submits this five-year career development plan under the mentorship of Dr. Merlin. The award will be used to i) mechanistically develop his initial observations showing that downregulation of CD98 in the intestinal epithelium under pathological conditions modulates inflammation; ii) receive hands-on training in molecular biology, microbiology, and immunology; iii) develop the therapeutic strategy based on CD98 targeting by nanotechnology; iv) attend and present at academic seminars and conferences (e.g. DDW and FASEB), and receive guidance from a selected Career Development Research Advisory Committee.

描述（由适用提供）：CD98在协调肠上皮事件中起重要作用，例如粘合/极性，氨基酸转运和直接结合O细胞表面分子。 CD98在细胞外C末端尾部具有PDZ结合结构域的独特分子取向表明，细胞外信号传导在其倍增功能中起作用。例如，CD98的磷酸化增强了异型细胞 - 细胞相互作用，并且具有丝氨酸磷酸化位点的细胞外结构域对这种效果至关重要。在炎症感染条件（例如炎症性肠病（IBD））中，CD98表达增加。较早的研究支持肠上皮细胞特异性CD98诱导屏障功能障碍并刺激促炎性介体的产生的能力。我们小组的研究集体表明，CD98表达在人类肠道肠病（IBD）的发病机理中起作用。我们的总体假设是，结肠CD98在发起和永久性肠coltis中起着至关重要的作用。该提案的最初目的是研究CD98/细菌相互作用在肠道功能丧失中的作用。我们还将专注于确定CD98在赞助结肠炎中的作用。 CD98表达在发炎的结肠中的敲低效率将随后设想，提出的实验将促进CD98在肠道注射中功能作用的分子机制鉴定，并允许发展靶向肠道炎症条件的理论理论（包括IBD）。我的第一个目的将集中于研究是否参与肠道屏障功能丧失的肠上皮CD98和CD98/细菌相互作用。我们组获得的初步数据表明，结肠CD98的过表达增加了肠道通透性，细菌易位和促炎性细胞因子的表达，例如IL-1？和TNF。我们的最初目的是研究细菌是否在特定的过表达结肠CD98的小鼠中启动脑屏障功能。具体而言，villin-CD98+/+转基因小鼠将用抗生素治疗，并且在未治疗的villin-CD98+/+转基因小鼠中评估的这些动物中的肠屏障功能和细胞因子表达。其次，CD98与细菌之间的直接相互作用及其信号传导过程将通过EX和体内方法研究。这些实验应阐明CD98表达和CD98/细菌相互作用在肠屏障功能丧失中的顺序作用。这，我的第二个目标将研究结肠CD98表达对结肠炎的调节的影响。我们已经证明，与野生型动物相比，villin-CD98转基因小鼠（在结肠细胞中表达的CD98表达CD98）聚集了DSS诱导的结肠炎。相比之下，与具有较高的结肠CD98表达（CD98FL/+）相比，具有低结肠CD98表达（CD98FL/+Villin-CRE）的小鼠对DSS具有更大的抵抗力。我们建议通过评估IL-10 - / - / - /CD98FL/+ Villin-CRE，IL-10-/ - / - / - /Villin-CD98+/+/+/+/ - / - / - / - / - / - /CD98FL/+动物来确定CD98表达在慢性结肠炎中的作用。最后，我的第三个目标将使用包裹在纳米颗粒（NP）中的非病毒载体作为载体作为载体有效抑制诱导的结肠炎的非病毒载体来调查ANT-CD98 siRNA的位置输送。最近，我们描述了一种针对结肠的原始技术，该技术用NP中的抗炎分子进行了抗炎分子，并封装在算法 - 壳聚糖水凝胶中。使用这项技术，我们获得了初步数据，表明TNF siRNA负载的NP抑制肠炎。我们进一步建议将CD98 siRNA特异性地靶向并输送到具有诱导结肠炎的小鼠中过表达CD98的结肠（上皮和免疫）细胞。 公共卫生相关性：这是一项指导的研究科学家发展奖，旨在通过对消化系统疾病的专业培训进行生物化学家，纳米技术学家和身体化学家Hamed Laruui博士的申请。他从他的心理上开始了一项独立的研究，该研究是关于CD98的生理和生物学作用，CD98是一种糖蛋白，它是肠上皮中的异二聚体。他将利用这个奖励机会将自己的研究兴趣从基本生物学转移到基于CD98的潜在治疗治疗方法，从而使自己与心理区分开。他的主要假设是在病理状况调节感染下，在肠上皮的CD98暂时下调。作为佐治亚州立大学的新助理教授，Laruui博士在Merlin博士的心态下提交了这项为期五年的职业发展计划。该奖项将用于i）机械地发展他的最初观察结果，表明在病理条件调节炎症下肠上皮下CD98的下调； ii）接受分子生物学，微生物学和免疫学的动手培训； iii）制定基于纳米技术靶向CD98的治疗策略； iv）参加并在学术中心和会议（例如DDW和FASEB）参加，并从选定的职业发展研究咨询委员会获得指导。