EUBACTERIA IN PATHOGENESIS OF SYSTEMIC LUPUS ERYTHEMATOSUS

真细菌在系统性红斑狼疮发病机制中的作用

• 批准号: 6478878
• 负责人: SHIRLEY A KOVACS
• 金额: $ 3.22万
• 依托单位: CALIFORNIA STATE UNIVERSITY FRESNO
• 依托单位国家: 美国
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-06-01 至 2002-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6478878
• 关键词: RNA splicing; RNase protection assay; antigen antibody reaction; autoantibody; bacterial antigens; disease /disorder etiology; enzyme linked immunosorbent assay; gene complementation; immunofluorescence technique; laboratory mouse; northern blottings; nucleic acid hybridization; nucleic acid sequence; pathologic process; photosynthetic bacteria; polymerase chain reaction; proliferating cell nuclear antigen; ribonucleoproteins; systemic lupus erythematosus; western blottings

Systemic Lupus Erythematosus (SLE) is an autoimmune arthritic disease of unknown etiology but behaves as an antigen-driven response to the nuclear component, U1 small nuclear ribonucleoprotein particle (U1snRNP). U1nsRNPs are highly conserved among eukaryotes but not thought to exist in prokaryotic organisms. However our work suggests that ribonucleoprotein particles displaying high homology to U1snRNPs do exist among eubacteria. As bacterial snRNPs could provide an antigenic stimulus which might lead to autoimmunity, a small group of SLE-susceptible MRL-lpr/lpr mice were injected with extracts from one of the "U1snRNP"-positive bacteria. The mice injected with bacterial extracts displayed early expression of certain clinical and immunological symptoms of SLE, commencing about two weeks after inoculation (mice were one month old at inoculation). This proposal intends to examine the details of this immune response through variations in immunization dose and time relevant to "natural" disease course and to include more thorough clinical, histopathological and immunological assessments of the outcomes. Clinical criteria will principally include assessments of arthritis, lymph node hyperplasia and alopecia; histopathological criteria will principally monitor tissue abnormalities in joints, kidneys and lymph nodes; and immunologic criteria will use ELISA reactivity to human nuclear extract and to bacterial extract for titers and isotypic profiles, direct immunofluorescence to detect glomerulonephritis, indirect immunofluorescence to detect reactivity to specific nuclear antigens, and western blotting to determine reactivity to U1snRNP-specific proteins MRL-lpr/lpr mice immunized with physiological saline and random genetic mice (Swiss-Webster) injected either the bacterial extract or saline will serve as experimental controls. Other candidate "U1snRNP"- containing bacterial organisms will be identified and/or evaluated using computer-based genomics, the polymerase chain reaction (PCR), northern hybridization and RNase protection assays, and mRNA splicing- complementation assays. Finally, the ability of these candidate prokaryotic cell extracts to stimulate SLE will be assessed by immunization of MRL-lpr/lpr mice and assessment of clinical, histopathological and immunological symptoms. The outcome of these experiments should provide a cleared indication of whether: inoculation with pro-karyotic cells; and these latter pro-karyotic cells can also stimulate SLE symptoms in MRL-lpr/lpr model mice. The possibility that bacteria are etiological agents of SLE unveils a wealth of antibiotic therapeutic opportunities for treatment of SLE or other autoimmune, rheumatological disorders.

系统性红斑狼疮（SLE）是一种病因不明的自身免疫性关节炎疾病，但表现为对核组分U1小核核糖核蛋白颗粒（U1 snRNP）的抗原驱动反应。 U1 nsRNP在真核生物中高度保守，但不认为存在于原核生物中。然而，我们的工作表明，核糖核蛋白颗粒显示高同源性U1 snRNP确实存在于真细菌。由于细菌snRNP可以提供可能导致自身免疫的抗原刺激，因此向一小组SLE易感的MRL-lpr/lpr小鼠注射来自“U1 snRNP”阳性细菌之一的提取物。注射细菌提取物的小鼠显示出SLE的某些临床和免疫学症状的早期表达，在接种后约两周开始（小鼠在接种时为一个月大）。该提案旨在通过与“自然”病程相关的免疫剂量和时间变化来检查这种免疫反应的细节，并包括对结果进行更彻底的临床、组织病理学和免疫学评估。临床标准将主要包括关节炎、淋巴结增生和脱发的评估;组织病理学标准将主要监测关节、肾脏和淋巴结的组织异常;免疫学标准将使用对人核提取物和细菌提取物的ELISA反应性来检测滴度和同种型分布，直接免疫荧光检测肾小球肾炎，间接免疫荧光检测对特异性核抗原的反应性，和蛋白质印迹以确定对U1 snRNP特异性蛋白质的反应性，用生理盐水免疫的MRL-lpr/lpr小鼠和注射细菌提取物或盐水的随机遗传小鼠（Swiss-Webster）将用作实验对照。将使用基于计算机的基因组学、聚合酶链反应（PCR）、北方杂交和RNA酶保护试验以及mRNA剪接-互补试验鉴定和/或评价其他候选含“U1 snRNP”的细菌微生物。最后，这些候选原核细胞提取物刺激SLE的能力将通过免疫MRL-lpr/lpr小鼠和评估临床、组织病理学和免疫学症状来评估。这些实验的结果应该提供一个明确的指示，是否：接种pro-SLE细胞;和这些后者pro-SLE细胞也可以刺激SLE症状的MRL-lpr/lpr模型小鼠。细菌是SLE的病原体的可能性揭示了用于治疗SLE或其他自身免疫性、风湿性疾病的大量抗生素治疗机会。