Cytokine mechanisms in systemic lupus erythematosus

描述（由申请人提供）：系统性红斑狼疮（SLE）是一种流行的人类全身性自身免疫性疾病，其发病机制仍不清楚。因此，旨在了解疾病机制的努力是高度相关的。由于多种原因，研究患有SLE的人类是困难的，我们已经开发了新的遗传上易患狼疮的NZBxNZW衍生的Stat-4或Stat-6缺陷的同源NZM系。Stat缺陷小鼠提供了独特的工具，以更好地理解autoAb和细胞因子在疾病发病机制中的作用，并可能允许解剖介导SLE肾损伤的机制。在大量初步数据的支持下，我们提出解决以下问题：（1）Stat 4缺陷型狼疮小鼠的肾脏疾病是依赖还是独立于自身抗体？为此，我们已经产生了B细胞缺陷型NZM 2328突变小鼠，我们将在不存在循环可溶性自身抗体的情况下恢复B细胞，然后将这些小鼠与Stat 4 KO杂交。(2)IFN-γ对于Star缺陷型NZM小鼠中自身抗体和靶器官疾病的发展是否必要？这一特定目的将检验以下假设：IFN γ的缺乏可能通过Stat 4-/-小鼠中调节机制的失效导致疾病的早期开始。为了实现这一点，我们将使用两种不同的方法直接和系统地测试IFN γ在Stat缺陷型NZM小鼠中狼疮样疾病发展的不同阶段的作用：a）使用IFN γ和抗IFN γ试剂的体内治疗方案，持续限定的时间段，和B）遗传方法，其中将以组织和时间特异性方式开发IFN γ的条件表达系统。(3)我们能在免疫缺陷的NZM小鼠中重建Stat缺陷表型吗？为了实现这一点，我们将通过在IL-7 R α和c-kit受体中引入功能缺失突变来产生完全免疫缺陷的NZM 2328，该突变允许用任何供体菌株进行造血重建，而不需要给予移植前调节。(4)两种Stat 4亚型对NZM 2328狼疮小鼠的免疫系统和靶器官有何直接影响？为此，我们将通过与Stat 4-α和Stat 4-β转基因小鼠杂交来恢复Stat 4缺陷型NZM 2328小鼠T淋巴细胞中的Stat 4，并将使用微阵列技术研究这些狼疮小鼠淋巴细胞和肾小球中的差异表达基因。这些研究将有助于更好地了解SLE的一些特征，并可能导致识别新的治疗靶点。

DESCRIPTION (provided by applicant): The pathogenesis of systemic lupus erythematosus (SLE), a prevalent human systemic autoimmune disease, is still unknown. Thus, efforts aimed at understanding disease mechanisms are highly relevant. Because studying humans with SLE is difficult for multiple reasons, we have developed novel genetically lupus-prone NZBxNZW derived congenic NZM lines that are either Stat-4 or Stat-6 deficient. The Stat deficient mice offer unique tools to achieve a better understanding of the role that autoAbs, and cytokines play in the pathogenesis of the disease and may allow dissection of the mechanisms that mediate renal damage in SLE. Backed up by substantial preliminary data, we propose to address the following questions: (1) Is the kidney disease in Stat4 deficient lupus mice dependent or independent of autoAbs? To this end we have produced B-cell deficient NZM2328 mutant mice into which we will restore B cells in the absence of circulating, soluble autoAbs and then cross these mice with Stat4 KO. (2) Is IFN-gamma necessary for the development of autoAbs and target organ disease in Star-deficient NZM mice? This specific aim will test the hypothesis that the absence of IFNgamma may result in early initiation of disease through a failure of regulatory mechanisms in the Stat4-/- mice. To accomplish this we will test directly and systematically the role of IFNgamma at different stages of lupus-like disease development in Stat deficient NZM mice using two different approaches: a) in vivo treatment protocols using IFNgamma and anti-IFNgamma reagents for defined periods of time, and b) a genetic approach in which a conditional expression system for IFNgamma in a tissue-and time-specific manner will be developed. (3) Can we reconstitute the Stat deficient phenotypes in immunodeficient NZM mice? To accomplish this, we will generate NZM2328 completely immunodeficient by introducing a loss of function mutation in both the IL-7R alpha and c-kit receptors that allows hematopoietic reconstitution with any donor strain without requiring administration of pre-transplant conditioning. (4) What are the direct effects of the two Stat4 isoforms on the immune system and on the target organ in NZM2328 lupus mice? For this purpose we will restore Stat4 in T lymphocytes of Stat4 deficient NZM2328 mice by crossing them with Stat4- alpha and Stat4-beta transgenic mice and will study differentially expressed genes in lymphocytes and glomeruli of these lupus mice using micro-array technology. These studies should lead to better understanding of a number of characteristics of SLE and may lead to identification of new targets for therapy.