DNA Vaccination for Autoimmunity Immunoinhibitory GpG Mo

细菌DNA和免疫刺激性CpG寡核苷酸（CpG-ODN）激活先天免疫系统以产生促炎细胞因子。刺激性CpG基序被证明是有效的Th 1样佐剂，目前被用作感染性疾病、肿瘤、过敏和自身免疫性疾病的各种动物模型的有效治疗性疫苗。我们已经表明，使用编码IL-4和髓磷脂蛋白的DNA的共接种策略，可以诱导抗原特异性Th 2对髓磷脂的免疫。这种方法改善并实际上逆转了正在进行的EAE。我们最近发现，免疫抑制性GpG-ODN的应用，具有从CpG到GpG的单碱基转换，可以有效地抑制其CpG-ODN对应物的免疫刺激反应。此外，这种抑制性GpG-ODN不仅能够在体外抵消CpG-ODN的刺激作用，它还能够抑制小鼠实验性自身免疫性脑脊髓炎（EAE）（一种Th 1介导的多发性硬化症动物疾病模型）的疾病严重程度，并诱导Th 2转变，就像DNA与基因共接种一样 编码髓磷脂和IL-4 [Garren et al，2001]。我们将探索GpG基序在自身免疫性疾病治疗中的应用，并研究其发挥作用的潜在机制。我们将扩展临床前研究的机制，从而GpG-ODN诱导减少表达的MHC II类，促进Th 2的转变，并增强抗原特异性Th 2反应。我们将测试使用GpG-ODN加编码髓鞘的基因的联合疫苗接种策略，以预防和逆转急性EAE，并阻止进一步复发，如果在慢性复发性EAE的初始急性发作后给予。当编码髓鞘蛋白的DNA疫苗用于治疗急性发作后的复发缓解型EAE时，我们将使用我们最近开发的蛋白质组髓鞘阵列来监测表位扩散和T细胞应答的性质。

Bacterial DNA and immunostimulatory CpG oligonucleotides (CpG-ODN) activate the innate immune system to produce proinflammatory cytokines. Shown to be potent Th1-like adjuvants, stimulatory CpG-motifs are currently utilized as effective therapeutic vaccines for various animal models of infectious diseases, tumors, allergies, and autoimmune diseases. We have shown that it is possible to induce antigen specific Th2 immunity to myelin, using a co-vaccination strategy with DNA encoding IL-4 and myelin proteins. This approach ameliorated and actually reversed ongoing EAE. We recently discovered that the application of an immunoinhibitory GpG-ODN, with a single base switch from CpG to GpG, can effectively inhibit the immunostimulatory response of its CpG-ODN counterpart. Moreover, this inhibitory GpG-ODN is not only capable of counteracting the stimulatory effect of CpG-ODN in vitro, it is also capable of suppressing the disease severity of experimental autoimmune encephalomyelitis (EAE) in mice, a Th1-mediated animal disease model for multiple sclerosis, and inducing a Th2 shift, much as DNA co-vaccination with genes encoding myelin and IL-4 [Garren et al, 2001]. We will explore the utility of the GpG motif for therapy of autoimmune disease, and examine the underlying mechanism whereby it exerts its effects. We will extend pre-clinical studies on the mechanism whereby GpG-ODN induces reduced expression of MHC class II, promotes a Th2 shift, and enhances antigen specific Th2 responses. We will test a co-vaccination strategy using GpG-ODN plus genes encoding myelin to prevent and reverse acute EAE, and to block further relapses, if given after the initial acute attack in chronic relapsing EAE. We will use our recently developed proteomic myelin array to monitor epitope spreading and the nature of the T cell response, when DNA vaccines encoding myelin proteins are used to treat relapsing remitting EAE after the acute attack.