Gene expression profiling of marrow-derived dendritic cells from non-obese diabetic mice

在I型糖尿病中，树突状细胞起着关键作用；它们保留激活外周自身反应性T细胞的能力，但不能以耐受性方式处理和/或重新表达自身抗原。已有NOD小鼠DC表型和功能异常的报道。为了研究NOD小鼠骨髓来源的CD11c^+DC的分子变化，我们最近比较了这些细胞和非小鼠来源的DC的转录谱。NOD来源的DC与非小鼠来源的DC相比，IL-6的mRNA表达降低了8倍。在这项研究中，我们检测了NOD小鼠DC产生IL-6的情况，以证实这种细胞因子在蛋白质水平上的减少。在分化过程中补充IL-6对DC表型和功能的影响也进行了研究。4周龄雌性小鼠的骨髓细胞在GM-CSF和IL-4的存在下培养超过6天，并添加或不添加IL-6。5 mg/mlLPS刺激NOD组DC分泌IL-6(10970±1685.0 pg/ml)明显低于非NOD组(45845±3506.6 pg/ml，P<0.05)。以琥珀酸四氮唑还原酶活力(琥珀酸四氮唑还原酶活力)测定，添加IL-6(2 ng/ml)的NOD诱导的CD4~+细胞对同基因混合淋巴细胞反应的反应性显著高于不加IL-6的DC(光密度0.36±0.031比0.23±0.027，刺激反应比=1：20，P<0.05)。SMLR的上调与DC表达CD80和CD86的中位荧光强度(CD80116±4.39vs92.1±2.75，p&lt；0.05；CD86，13.2±1.50vs9.77±0.289，p&lt；0.05)和IFNG的产生显著降低(412.1±40.94vs1639±131.6pg/ml，p&lt；0.05)有关。

In type I diabetes mellitus, dendritic cells play pivotal roles ; they retain capacity to activate autoreactive T cells in the periphery, but are unable to process and/ or resent autoantigens in a tolerogenic fashion. Abnormal phenotype and function of DC from NOD mice have been reported. To characterize molecular changes in Cd11c^+ bone marrow-derived DC from NOD mice, we recently compared the transcript profiles of these cells with those from NON mice. DC from NOD showed 8-fold reduced interleukin 6 (IL-6) mRNA expression compared to those from NON mice. In this study, we examined IL-6 production by DC from NOD mice to confirm the decreased production of this cytokine at protein level. Effect by IL-6 supplementation during differentiation on the phenotype and function of DC was also investigated.Bone marrow cells from 4-week-old female mice were cultivated in the presence of GM-CSF and IL-4 over 6 days, with or without IL-6 supplementation. CD11c^+ DC were sorted by magnetic beads-conjugated with anti-CD11c antibodies (MACS^<TM>).DC from NOD produced significantly lower amount of IL-6 in response to 5 mg/ ml LPS (10970±1685.0 pg/ml) than those from NON (45845±3506.6 pg/ml, p<0.05, Mann-Whitney U test). DC from NOD generated with additional IL-6 (2ng/ml) elicited significantly higher response by CD4^+ cells in the syngeneic mixed lymphocyte reaction (SMLR), measured by succinate-tetrazolium reductase activity (WST-1^<TM>), than those without IL-6 (optic density 0.36±0.031 vs 0.23±0.027, stimulator : responder ratio=1:20,p< 0.05). The up-regulated SMLR was associated with increased median fluorescent intensity of CD80 and CD86 expression by DC (CD80, 116±4.39 vs 92.1±2.75, p<0.05; CD86, 13.2±1.50 vs 9.77±0.289,p<0.05), and significantly lower IFNg production in the SMLR (412.1±40.94 vs 1639±131.6pg/ml,p<0.05).Reduced autocrine secretion of IL-6 by DC may lead to defective phenotype and function of DC, and then to Th1-deviated immune reaction in NOD mice.