Islet growth in NOD mice tolerant to autoimmune diabetes

描述(由申请人提供)： 这项建议的目标是通过诱导对自身免疫过程的耐受性和补充前体细胞中丢失的胰岛细胞来逆转1型糖尿病。Herold博士之前的临床研究表明，使用抗CD3单抗治疗可以防止糖尿病发作后长达两年的胰岛素产生损失，临床前研究表明，抗CD3单抗可以诱导对自身免疫性疾病的耐受。然而，为了建立正常的代谢控制，这种治疗必须结合一种补充丢失的胰岛组织的方法。我们将测试在诱导免疫耐受后，胰岛是否会再生，是否能被刺激生长，或者来自胰腺原的胚胎干细胞是否可以用来补充丢失的β细胞团。该提案将发展凯文·赫罗德博士和弗吉尼亚·帕帕约安努博士之间的伙伴关系，前者从事1型糖尿病的免疫学和免疫疗法，后者是发育生物学领域的专家，但此前从未在糖尿病领域工作过。我们将首先确定NOD小鼠对自身免疫性糖尿病的免疫耐受诱导是否会导致胰岛细胞增殖。这一目标的研究将包括发育中的胰岛素+细胞的免疫组织化学和分子分析。我们将测试在非免疫介导的胰岛素缺乏动物模型中，Exendin-4和肝细胞生长因子是否可以刺激胰岛细胞再生，从而刺激β细胞的发育。我们将测试干细胞能否通过将正常MHC相合的小鼠的胰腺Anlagen移植到抗CD3单抗治疗的糖尿病NOD小鼠身上而培养成能够纠正糖尿病的胰岛。将研究分化为成熟的胰腺细胞，标记荧光色素的供体将使我们能够识别任何新分化的胰岛素+细胞的来源。通过比较有无抗CD3单抗处理后的高血糖或正常血糖，我们将能够获得更多的信息，包括疾病相关胰岛抗原的表达，以及胰岛素和葡萄糖对胰岛细胞分化的影响。赫罗德博士和帕帕约安努博士将密切合作，特别是在拟议的分子和干细胞研究方面。通过结合两个PL的专业知识来解决胰岛自身免疫和β细胞缺陷的问题，我们的建议将测试一种可能对患者有用的组合策略。

DESCRIPTION (provided by applicant): The goal of this proposal is to reverse Type 1 diabetes by inducing tolerance to the autoimmune process and replenishing lost islet cells from precursors. Previous clinical studies by Dr. Herold have shown that treatment with an anti-CD3 monoclonal antibody can prevent the loss of insulin production for up to 2 years after onset of diabetes, and preclinical studies suggest that anti-CD3 mAb induces tolerance to the autoimmune disease. However, to establish normal metabolic control, this therapy must be combined with a means of replenishing lost islet tissue. We will test whether, after induction of immunologic tolerance, islets will regenerate, can be stimulated to grow, or whether embryonic stem cells from the pancreatic anlagen may be used to replenish the lost beta cell mass. The proposal will develop a partnership between Dr. Kevan Herold, whose work has been in the immunology and immunotherapy of Type 1 diabetes and Dr. Virginia Papaioannou, who is an expert in the field of developmental biology but who has not previously worked in the field of diabetes. We will first determine whether induction of immune tolerance to autoimmune diabetes in the NOD mouse results in islet cell proliferation. Studies in this aim will include immunohistochemical and molecular analyses of developing insulin+ cells. We will test whether islet cell regeneration can be stimulated using exendin-4 and hepatocyte growth factor which can stimulate beta cell development in non-immune mediated animal models of insulin deficiency. We will test whether stem cells can be grown into islets that can correct diabetes by transplanting pancreatic anlagen from normal MHC matched mice into diabetic NOD mice treated with anti-CD3 mAb. Differentiation into mature pancreatic cells will be studied, and a fluorochrome tagged donor will enable us to identify the source of any newly differentiated insulin+ cell. By comparing this process in the presence or absence of anti-CD3 mAb treatment with hyper or euglycemia, we will be able to obtain additional information including expression of disease relevant islet antigens, and the effects of insulin and glucose on differentiation of islet cells. Drs. Herold and Papaioannou will collaborate closely particularly in the molecular and stem cell studies proposed. By combining the expertise of the two Pl's to address the problems of islet autoimmunity and beta cell deficiency our proposal will test a combination strategy that may be useful in patients.