Innate and Adaptive Immunity in Childhood Epilepsy

描述(由申请人提供)：从童年开始的顽固性癫痫的长期神经后遗症确实是毁灭性的。传统的抗癫痫药物不仅不足以控制癫痫发作，而且会造成有害的副作用，进一步加重癫痫儿童的发展负担。迫切需要防止癫痫进展和限制与癫痫发作相关的细胞损伤的替代疗法。异常的先天免疫反应、外周炎性细胞的渗透和血脑屏障的破坏与癫痫的发生、发展和持续存在有关。我们实验室最近在全基因组范围内寻找新的药物靶点，发现促炎分子可能是癫痫发病过程中的治疗靶点。我们已经建立了一种新的临床相关的小鼠模型，即延长的热性惊厥(FCS)，然后在生命的后期由“二次打击”红藻氨酸诱导癫痫发作。我们的初步结果是，使用无偏倚的流式细胞术分析炎性细胞，在有早期癫痫经历的动物中，在二次打击后，CNS浸润性和CNS驻留的免疫细胞都显著增加。使用我们的“两次打击”模型，我们建议检验这一假设，即先天和获得性免疫反应在调节早期癫痫发作的长期致痫效应中起因果作用。具体目的是：(1)为了验证对FCS的免疫反应可增加随后癫痫的易感性的假设，我们将确定抗炎药物米诺扎克或ACTH能否预防早期FCS的急性促炎细胞因子的产生和长期的致痫作用；(2)为了区分天然免疫和获得性免疫在早期发热性惊厥的致敏作用，我们将利用Cx3cr1EGFP/+转基因小鼠、双色MCP-1：：mRFP1；CCR2：CCR2-EGFP报告小鼠以及多色流式细胞术分析来检测和定量固有免疫细胞和获得性免疫细胞。3.为了直接探讨中枢神经系统驻留和外周炎性细胞在致痫过程中的作用，我们将在遗传不能获得天然免疫(MyD88-/-)或获得性免疫(Rag1-/-)的小鼠身上测试我们的癫痫模型。这些研究的结果将揭示适应性免疫和先天免疫在早期生命开始的癫痫形成过程中的相对贡献。这一结果也应该确定抗炎药物对早期抗癫痫治疗的潜在有益影响。

DESCRIPTION (provided by applicant): The long-term neurological sequelae of intractable epilepsy that begins in childhood are truly devastating. Conventional antiepileptic drugs are not only inadequate to control seizures, but can cause detrimental side effects to further burden the development of children with epilepsy. Alternative therapies that prevent the progression of epilepsy and limit cellular injury associated with seizures are critically needed. A dysregulated innate immune response, peripheral inflammatory cell infiltration and breakdown of the blood- brain barrier have been implicated in the initiation, progression and perpetuation of seizures. A recent genome-wide search to identify novel drug targets in our laboratory has revealed that proinflammatory molecules may be therapeutic targets in the epileptogenic process. We have developed a new clinically relevant murine model of prolonged febrile convulsions (FCs) followed by "second hit" kainic acid-induced seizures later in life. Our preliminary results using an unbiased flow cytometric analyses of inflammatory cells detected significant increases in both CNS-infiltrating and CNS- resident immune cells after a "second hit" in animals with prior experience of early-life seizures. Using our "two hit" model, we propose to test the hypothesis that innate and adaptive immune responses play a causal role in mediating the long-term epileptogenic effects of early life seizures. The Specific Aims are: (1) To test the hypothesis that immunologic responses to FCs cause heightened susceptibility to subsequent seizures, we will determine whether the acute pro-inflammatory cytokine production and long-term epileptogenic effect of early-life FCs is prevented by post-treatment with an anti- inflammatory drug minozac or ACTH; (2) To distinguish the involvement of innate and adaptive immunity in the sensitizing effects of early-life febrile convulsions, we will utilize Cx3cr1EGFP/+ transgenic mice, dual-color MCP-1::mRFP1;CCR2::CCR2-EGFP reporter mice, and multi-color flow cytometric analysis to detect and quantify innate and adaptive immune cells. 3. To directly address the role of CNS-resident and peripheral inflammatory cells in the epileptogenic process, we will test our epilepsy model in mice genetically incapable of mounting innate (MyD88-/-) or adaptive (Rag1-/-) immunity. Results of these studies will reveal the relative contributions of adaptive and innate immunity to the epileptogenic process that starts in early life. The results should also determine the potential beneficial impact of anti-inflammatory drugs for early anti- epileptic therapy.