Characterization of a novel T cell activating protein in arthritis

关节炎中新型 T 细胞激活蛋白的表征

• 批准号: 7774332
• 负责人: Raphael Hirsch
• 金额: $ 33万
• 依托单位: UNIVERSITY OF PITTSBURGH AT PITTSBURGH
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-04-01 至 2014-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7774332
• 关键词: Adult; Apoptotic; Architecture; Arthritis; Birth; Bone Density; Cartilage; Cells; Computers; Development; Disease; Embryonic Development; Follistatin; Follistatin-Related Protein 1; Gene Transfer; Human; IL2RA gene; Inflammation; Inflammatory; Inflammatory Response; Interferons; Interleukin-1; Interleukin-12; Interleukin-17; Interleukin-2; Joints; Mediating; Mediator of activation protein; Monoclonal Antibodies; Mus; Osteoblasts; Osteoclasts; Osteocytes; Osteogenesis; Phenotype; Physiology; Play; Production; Property; Proteins; Rheumatoid Arthritis; Role; Signal Transduction; Structure; T-Cell Activation; T-Cell Depletion; T-Lymphocyte; Time; Wild Type Mouse; X-Ray Computed Tomography; bone; cytokine; joint destruction; mineralization; mouse model; novel; protein structure; public health relevance; receptor; response; tomography; tool

DESCRIPTION (provided by applicant): We have discovered that a novel protein, follistatin-like-1 (FSTL-1), is highly expressed in the joints of mice and humans with arthritis, especially at the interface of synovial pannus and eroding bone. A key role for FSTL- 1 in arthritis progression was confirmed by suppression of disease by FSTL-1 neutralization. Our studies indicate that FSTL-1 is a co-stimulator of T cells. We will characterize FSTL-1 and its contribution to inflammatory arthritis in mouse models of disease, with detailed study of T cell activation. The first Aim is to determine the role of FSTL-1 in the normal joint. Our studies demonstrate that FSTL-1 is produced at low levels in the adult mouse joint. FSTL-1 is induced in osteoblasts by TGF-2, a key bone regulatory factor, and FSTL-1 is an arthritis progression factor, but the role of FSTL-1 in normal bone and joint physiology is not characterized. We will determine the cells responsible for FSTL-1 production within the joint during embryogenesis and post-natal development. We will characterize the role of FSTL-1 using a new FSTL-1 hypomorphic (knockdown) mouse by assessing the effect of FSTL-1 under-expression on joint structure at birth and during development to adulthood, bone formation and architecture, bone density and strength, and cartilage integrity. The second Aim is to determine the contribution of FSTL-1 to arthritis. FSTL-1 is induced by IL-12 and FSTL-1 is increased in arthritic joints, where it plays a pro-inflammatory role. These findings suggest that bone is not solely a target of arthritis, but plays an active role in joint destruction. We will characterize the contribution of bone to arthritis progression, focusing on FSTL-1 as a mediator. FSTL-1 will be over-expressed by gene transfer, under-expressed using the FSTL-1 hypomorphic mouse, and neutralized at various times during arthritis using anti-FSTL-1 monoclonal antibody. We will compare the effects of varying FSTL-1 expression on the inflammatory pannus, cartilage and bone formation and erosion, bone formation rate by dynamic histomorphometry, changes in mineralization by micro computer tomography, changes in osteoclastic activity and matrix cells, and expression of pro-inflammatory cytokines induced in response to FSTL-1. The third Aim is to determine how FSTL-1 activates T cells and induces IFN-3 secretion. FSTL-1 promotes inflammation by enhancing IFN-3 signaling. The inflammatory response is dependent on T cells, as T cell depletion abolishes FSTL-1-induced paw inflammation. Furthermore, FSTL-1 prolongs expression of the T cell activation molecule, CD25. To characterize the T cell activating properties of FSTL-1, we will determine the T cell activation phenotype induced by FSTL-1, whether FSTL-1 stabilizes TCR mediated signaling by inducing anti-apoptotic molecules, whether FSTL-1 stimulates T cells directly or indirectly, the receptor for FSTL-1, the protein structure necessary for FSTL-1 activity, and whether FSTL-1 has additional actions on inflammation. Characterization of FSTL- advance understanding of arthritis and may provide new treatment options. PUBLIC HEALTH RELEVANCE: studies will characterize the role in arthritis and joint development of a novel mediator of arthritis progression, FSTL-1. Characterization of FSTL-1 will advance understanding of arthritis and may provide new treatment options.

描述（由申请人提供）：我们发现，一种新型蛋白质类似卵泡蛋白样-1（FSTL-1）在小鼠和人类的关节中高度表达，尤其是在滑膜pannus和骨骼的界面上。通过FSTL-1中和抑制疾病，FSTL-1在关节炎进展中的关键作用得到了证实。我们的研究表明，FSTL-1是T细胞的共同刺激剂。我们将在小鼠疾病模型中表征FSTL-1及其对炎症性关节炎的贡献，并详细研究T细胞激活。第一个目的是确定FSTL-1在正常关节中的作用。我们的研究表明，在成年小鼠关节中，FSTL-1在低水平中产生。 FSTL-1是通过TGF-2（一种关键的骨调节因子TGF-2诱导的成骨细胞诱导的），而FSTL-1是关节炎的进展因子，但是FSTL-1在正常骨和关节生理学中的作用尚未表征。我们将在胚胎发生和产后发育期间确定负责在关节内产生FSTL-1的细胞。我们将通过评估FSTL-1表达不足对出生时，发育到成年期间的关节结构的影响，使用新的FSTL-1型肌（敲低）小鼠来表征FSTL-1的作用。第二个目的是确定FSTL-1对关节炎的贡献。 FSTL-1由IL-12诱导，在关节炎关节中增加FSTL-1，在该关节中起促炎作用。这些发现表明骨骼不仅是关节炎的靶标，而是在关节破坏中起积极作用。我们将表征骨骼对关节炎进展的贡献，重点是FSTL-1作为介体。 FSTL-1将被基因转移过度表达，使用FSTL-1肌型小鼠表达不足，并使用抗FSTL-1单克隆抗体在关节炎期间的不同时间中和。我们将比较FSTL-1表达对炎症性Pannus，软骨和骨形成和侵蚀的影响，动态组织形态计量法，微型计算机层析成像的矿物质变化，骨质塑性性活性和基质细胞的变化以及对FSTL-1响应的炎性细胞因子的表达的变化。第三个目的是确定FSTL-1如何激活T细胞并诱导IFN-3分泌。 FSTL-1通过增强IFN-3信号传导促进炎症。炎症反应取决于T细胞，因为T细胞耗竭废除了FSTL-1诱导的PAW炎症。此外，FSTL-1延长T细胞活化分子CD25的表达。为了表征FSTL-1的T细胞激活特性，我们将确定FSTL-1诱导的T细胞激活表型，FSTL-1是否通过诱导抗凋亡分子诱导TCR介导的信号传导，FSTL-1是否直接刺激TT T细胞，无论是直接还是间接地刺激FSTL-1的受体，对于FSTL-1的受体，FSTL-1的动作，FSTL-1是否在FSTL-1上都具有FSTL的活性。 FSTL的表征对关节炎进行了预先理解，并可能提供新的治疗选择。公共卫生相关性：研究将表征关节炎的作用和联合发展的新型关节炎进展介体FSTL-1。 FSTL-1的表征将提高人们对关节炎的了解，并可能提供新的治疗选择。