IL2 DEFICIENCY MEDIATES AUTOIMMUNITY IN MRL-LPR MICE

IL2 缺乏介导 MRL-LPR 小鼠的自身免疫

• 批准号: 2081787
• 负责人: Ralph C Budd
• 金额: $ 17.54万
• 依托单位: UNIVERSITY OF VERMONT & ST AGRIC COLLEGE
• 依托单位国家: 美国
• 财政年份: 1993
• 资助国家: 美国
• 起止时间: 1993-12-10 至 1996-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2081787
• 关键词: CD4 molecule; CD8 molecule; T lymphocyte; autoimmunity; autoradiography; flow cytometry; gel mobility shift assay; gene expression; gene mutation; genetic regulatory element; genetic strain; human subject; interleukin 2; laboratory mouse; leukocyte activation /transformation; polymerase chain reaction; protein biosynthesis; systemic lupus erythematosus; transcription factor

Many induced models of autoimmunity necessitate augmenting the immune response to a specific target tissue. In distinction, several naturally arising mouse models of systemic lupus erythematosus (SLE) manifest hyporesponsive T lymphocyte responses, particularly regarding deficient IL2 production. This is strikingly present in the MRL-lpr mouse. These mice develop an SLE diathesis accompanied by an enormous accumulation of abnormal TCR-alphBeta+ CD2- B220- B220+ CD4-CD-8 T cells that produce negligible IL2 when activated and as a result, manifest little proliferative capacity. A such they resemble anergic T cells and other CD2-T cells. The lpr defect results form a mutation of the fas gene which mediates apoptosis. This may account for the pronounced accumulation of T cells, but does not readily explain the developmental arrest of these cells, nor the reason for the defect in signal transduction and hence IL2 production. This proposal will examine this defect at the level of the IL2 gene regulatory transcription factors. It will then assess the potential benefits of IL2 in vivo therapy in MRL- lpr mice and monitor the alterations in T cell phenotype and function that may be responsible for this. The first specific aim analyzes the expression of the IL2 gene regulatory transcription factors by gel mobility shift in fresh and cultured MRL-lpr CD4-8-, CD4+, and MRL+/+ T cells before and after activation with PMA and ionomycin, or anti-CD3 mAb. This will be compared to T cells stimulated with anti-CD3 mAb in the absence or presence of anti-fas mAb. This portion will define the nature of the IL2 defect in lpr CD4-8-T cells and help establish the contribution if fas in costimulation of IL2 production. The second specific aim will extend the preliminary in vitro observation that IL2 can induce cell cycling, CD2 induction, B220 loss, and gain of function by lpr CD4-8- T cells. MRL-lpr mice will be administered IL2 in vivo as a cDNA construct, as the phenotype and function of the CD4-9- monitored while the potential beneficial or detrimental effects on the autoimmune process are determined.

许多诱导的自身免疫模型需要增强免疫功能。 对特定靶组织的反应。 当然，几个自然 系统性红斑狼疮（SLE）小鼠模型的产生表现出 低反应性T淋巴细胞反应，特别是关于缺乏 IL 2产生。 这在MRL-lpr小鼠中显著存在。 这些 小鼠发展出SLE素质，伴随着大量的 产生异常TCR β + CD 2- B220- B220+ CD 4-CD-8 T细胞， 当被激活时，IL 2可以忽略不计，因此， 增殖能力 因此，它们类似于无反应性T细胞和其他细胞 CD 2-T细胞。 lpr缺陷是由fas基因突变引起的 介导细胞凋亡。 这也许可以解释 积累的T细胞，但并不容易解释发育 这些细胞的逮捕，也不是信号缺陷的原因 转导，从而产生IL 2。 本提案将审查这一点 在IL 2基因调节转录因子水平上的缺陷。 然后将评估IL 2在MRL中的体内治疗的潜在益处- lpr小鼠，并监测T细胞表型和功能的改变 可能是罪魁祸首 第一个具体目的是分析IL 2基因调控的表达， 在新鲜和培养的MRL-lpr中通过凝胶迁移率改变的转录因子 PMA活化前后的CD 4 -8-、CD 4+和MRL+/+ T细胞， 离子霉素或抗CD 3 mAb。 这将与T细胞刺激相比， 在不存在或存在抗fas mAb的情况下，用抗CD 3 mAb。 这 部分将定义lpr CD 4 -8-T细胞中IL 2缺陷的性质， 有助于确定Fas在IL 2共刺激中的作用 生产 第二个具体目标将扩大初步的体外 观察到IL 2可诱导细胞周期、CD 2诱导、B220丢失， 和通过lpr CD 4 -8- T细胞获得功能。 MRL-lpr小鼠将被 作为cDNA构建体在体内施用IL 2，作为表型， CD 4 -9的功能-监测，而潜在的有益或 确定对自身免疫过程的有害影响。