应用非清除性抗CD4和CD8抗体可使NOD小鼠糖尿病得到长期缓解
发布时间:2012-10-08 15:20:27浏览次数:3325次来源:摘译者和审校者均来自吉林大学白求恩第二医院 摘自:Diabetes. 2012 Jun 29. [Epub ahead of print].
1型糖尿病初发病时残存的β细胞如能免受进行性自身免疫的破坏,将足以控制高血糖。大量研究致力于发展免疫疗法,既可直接耐受或清除病理性的T细胞免疫效应物,又能提高调节性T细胞(Treg)数量。目前的挑战是如何发现一种免疫疗法,不仅可以选择性抑制致糖尿病性的免疫应答且有效逆转糖尿病,还可以建立长期的β细胞特异性免疫耐受以缓解病情。
在现阶段的研究中,研究人员发现给新发糖尿病的NOD小鼠短期注射非清除性抗体,特异性地与CD4和CD8协同抗体结合,可以迅速逆转临床糖尿病。腹腔注射两次YTS177(抗CD4抗体)和YTS105(抗CD8抗体),每次600–800 mg,在注射后的72小时内,小鼠的平均血糖从365 mg/dL降至231 mg/dL,其中54%的NOD小鼠的糖尿病病情得到缓解。这种保护效果一旦建立,病情的缓解将长期维持。绝大部分NOD小鼠在接受YTS治疗后,糖尿病缓解状态持续超过200天,最长可达400天,虽然这些小鼠在治疗后的4~5周体内已经检测不到YTS177和YTS105。此外,单独给予YTS177或YTS105治疗的NOD小鼠的糖尿病病情,即使得到缓解,也只是暂时性的,一般得不到缓解。
这种对病情缓解的诱导,涉及了胰岛选择性T细胞的清除、胰腺淋巴结的耗竭,以及胰腺固有的抗原提呈细胞对转化生长因子(TGF)-β1的上调。胰腺和胰腺淋巴结中的YTS介导的T细胞清除,并不依赖于T细胞凋亡。TGF-β1是YTS治疗诱导病情缓解所必需的,中和TGF-β1会阻断对病情缓解的诱导。在病情长期缓解的NOD小鼠中,β细胞特异性的免疫调节性T细胞和Foxp3+CD25+CD4+T细胞,选择性地存在于胰腺淋巴结中。缓解效果的维持与具有组织特异性的免疫调节性T细胞密切相关,病情缓解的NOD小鼠免疫系统并未受到抑制,对外源性抗原可做出正常的免疫应答,这种缓解具有β细胞特异性。YTS治疗不清除免疫系统中正常的T细胞,因此不会造成免疫抑制。
总之,这些结果证实,在临床糖尿病初发之时,应用非清除性抗体与CD4和CD8特异性结合,可以有效地诱导NOD糖尿病小鼠的病情缓解,抗CD4和抗CD8抗体疗法是建立长期β细胞特异性T细胞免疫耐受的一个强有力的方法。
Long-Term Remission of Diabetes in NOD Mice Is Induced by Nondepleting Anti-CD4 and Anti-CD8 Antibodies.
Residual β-cells found at the time of clinical onset of type 1 diabetes are sufficient to control hyperglycemia if rescued from ongoing autoimmune destruction. The challenge, however, is to develop an immunotherapy that not only selectively suppresses the diabetogenic response and efficiently reverses diabetes, but also establishes long-term β-cell-specific tolerance to maintain remission. In the current study, we show that a short course of nondepleting antibodies (Ab) specific for the CD4 and CD8 coreceptors rapidly reversed clinical disease in recent-onset diabetic NOD mice. Once established, remission was maintained indefinitely and immunity to foreign antigens unimpaired. Induction of remission involved selective T-cell purging of the pancreas and draining pancreatic lymph nodes and upregulation of transforming growth factor (TGF)-β1 by pancreas-resident antigen-presenting cells. Neutralization of TGF-β blocked the induction of remission. In contrast, maintenance of remission was associated with tissue-specific immunoregulatory T cells. These findings demonstrate that the use of nondepleting Ab specific for CD4 and CD8 is a robust approach to establish long-term β-cell-specific T-cell tolerance at the onset of clinical diabetes.
链接:http://diabetes.diabetesjournals.org/content/early/2012/06/25/db12-0098.long