Prostaglandin E synthase in rheumatoid arthritis

描述（由申请人提供）： 非甾体类抗炎药和特异性环氧合酶（考克斯）-2抑制剂治疗关节炎的有效性提供了临床证据，表明关节组织中前列腺素（PG）产生增加会导致疼痛、肿胀和僵硬症状。PG生物合成需要考克斯和PG合酶的顺序作用。在用促炎细胞因子刺激后，在许多不同的细胞类型（包括滑膜成纤维细胞）中存在PGE 2的优先增加。我们证明，增加PGE 2在人类原代滑膜细胞的促炎细胞因子是由于诱导微粒体PGE合酶（mPGES）-1。该提案的总体目标是表征mPGES-1和其他PGE脱氢酶在免疫炎症性关节炎中类花生酸生物合成中的作用。我们假设mPGES-1需要达到最大的PGE 2生产和mPGES-1衍生的PGE 2在塑造免疫炎症反应中的作用。我们建议使用特定的考克斯酶抑制剂和抑制性RNA（RNAi）来确定mPGES-1相对于其他合成酶在人滑膜成纤维细胞中PGE 2生物合成中的特定作用。我们将研究来自缺乏考克斯-1、考克斯-2或mPGES-1的小鼠的细胞中类花生酸的产生途径。将测定关节炎患者或非关节炎受试者的滑膜组织中考克斯和PGES酶的表达及其相对亚细胞定位。此外，我们将研究mPGES-1缺陷对遗传缺陷小鼠先天性和获得性免疫的影响。我们将确定类花生酸和细胞因子的巨噬细胞，脾细胞，树突状细胞在mPGES-1空小鼠。我们将确定mPGES-1缺陷对树突状细胞表型和功能的影响。我们将使用胶原诱导的关节炎和K/BxN血清模型来确定PGE 2在关节炎的免疫与炎症机制中的作用。这些数据将为确定mPGES-1是否是关节炎治疗干预的适当靶点提供科学依据。

DESCRIPTION (provided by applicant): The effectiveness of non-steroidal anti-inflammatory drugs and specific cyclooxygenase (COX)-2 inhibitors for treatment of arthritis provides clinical evidence that increased prostaglandin (PG) production in joint tissues contributes to symptoms of pain, swelling, and stiffness. PG biosynthesis requires the sequential action of COX and PG synthase enzymes. After stimulation with pro-inflammatory cytokines, there is a preferential increase in PGE2 in many different cell types, including synovial fibroblasts. We demonstrated that increased PGE2 in response to pro-inflammatory cytokines in human primary synovial cells is due to induction of microsomal PGE synthase (mPGES)-1. The overall goal of this proposal is to characterize the role of mPGES-1 and other PGE synthases in eicosanoid biosynthesis in immune inflammatory arthritis. We hypothesize a requirement for mPGES-1 to achieve maximal PGE2 production and a role for mPGES-1-derived PGE2 in shaping the immune inflammatory response. We propose to determine the specific role of mPGES-1 relative to other synthetic enzymes for biosynthesis of PGE2 in human synovial fibroblasts using specific COX enzyme inhibitors and inhibitory RNA (RNAi). We will investigate eicosanoid production pathways in cells from mice deficient for COX-1, COX-2 or mPGES-1. Expression of the COX and PGES enzymes in synovial tissues from patients with arthritis or non-arthritic subjects and their relative subcellular localization will be determined. In addition, we will examine the consequences of mPGES-1 deficiency for innate and acquired immunity in genetically null mice. We will determine eicosanoid and cytokine profiles of macrophages, splenocytes, and dendritic cells in mPGES-1 null mice. We will determine the impact of mPGES-1 deficiency on dendritic cell phenotype and function. We will determine the role of PGE2 on immune versus inflammatory mechanisms of arthritis using the collagen-induced arthritis and K/BxN serum models. These data will provide the scientific basis by which to determine if mPGES-1 is an appropriate target for therapeutic intervention in arthritis.