Peripheral whole blood FOXP3 TSDR methylation: a potential marker in severity assessment of autoimmune diseases and chronic infections

Immune dysregulation is a cardinal feature of autoimmune diseases and chronic microbial infections. In particular, regulatory T cells are downregulated in autoimmune diseases while upregulated in chronic microbial infections. FOXP3 is the master regulator of Treg development. Treg-specific demethylated region (TSDR) is a highly conserved locus on the FOXP3 gene that is fully demethylated in natural Tregs but methylated in effector T cells. In our study, we used high resolution melt-polymerase chain reaction (HRM-PCR) to determine the FOXP3 TSDR methylation status in autoimmune diseases and chronic microbial infections. We found that FOXP3 TSDR to have the highest mean melting temperature (highly methylated) in active SLE patients compared to all the other groups (p?<?0.001). The psoriasis group also had a significantly high mean melting temperature (78.62?±?0.20) when compared with the inactive SLE group (78.49?±?0.29, p?<?0.05) and control group (78.44?±?0.25, p?<?0.01). There was no significant difference in melting temperature between inactive SLE and healthy controls. Disease activity in SLE was directly associated with methylation of the FOXP3 TSDR. On the other hand, patients with chronic microbial infections had significantly lower FOXP3 TSDR mean melting temperature (demethylated) when compared with healthy controls (78.28?±?0.21 vs 78.44?±?0.25, p?<?0.05). Our results suggest that the use of HRM-PCR to detect FOXP3 TSDR methylation status is a reliable and easy method to predict natural regulatory T cell levels in peripheral blood in different disease conditions. Determining FOXP3 TSDR methylation status can be a useful tool in diagnosis, and monitoring the severity of autoimmune diseases and chronic microbial infections.     

Sirt5 is dispensable for BrafV600E‐mediated cutaneous melanoma development and growth in vivo

Sirt5 is known to functionally regulate mitochondrial proteins by altering posttranslational modifications, including lysine desuccinylation. While roles for Sirt5 as either a tumor promoter or suppressor, or in chemoresistance, have been implicated in other cancers, the function of Sirt5 in cutaneous melanoma has not been well examined. Therefore, to determine whether Sirt5 is necessary for Braf^V600E‐mediated melanoma formation and/or disease progression, we crossed a genetically engineered murine melanoma model (Tyr^CreERT2/+; Braf^{LSL‐V600E/+}; Pten^flox/flox) to Sirt5^?/? knockout animals. In addition, we tested for synergism with a selective BRAF (V600E) inhibitor in Sirt5^?/? mouse melanoma cells. Taken together, this report demonstrates that, in these models, Sirt5 is dispensable for Braf^V600E‐mediated cutaneous melanoma formation and growth in vivo, and does not improve sensitivity to a selective BRAF inhibitor.     

滋阴益肾法治疗特发性血小板减少性紫癜疗效及对患者血清IL-4、IL-6和免疫功能的影响

目的: 探讨滋阴益肾法治疗特发性血小板减少性紫癜(ITP)的疗效及对血清IL-4、IL-6、TNF-α及免疫功能的影响。方法:选取ITP患者84例,随机数字表法分为对照组和观察组,各42例。对照组采用口服泼尼松片治疗,观察组在对照组用药基础上给予滋阴益肾法治疗。比较两组临床疗效,治疗前后IL-4、IL-6、TNF-α、外周血T淋巴细胞亚群(CD₃⁺、CD₄⁺、CD₈⁺、CD₄⁺ /CD₈⁺)及免疫球蛋白水平变化情况。结果:两组治疗后中医症候积分明显降低,观察组优于对照组(P<0.05)。观察组总有效率95.24%高于对照组78.57%(P<0.05); 两组治疗后PLT计数均明显升高、PAIgG表达水平降低,观察组更明显(P<0.05); 两组治疗前IL-4、IL-6、TNF-α及外周血T淋巴细胞亚群水平比较差异无统计学意义(P>0.05); 治疗后CD₃⁺、CD₄⁺、CD₄⁺ /CD₈⁺均升高,IL-4、IL-6、TNF-α、CD₈⁺均降低(P<0.05); 观察组治疗后CD₃⁺、CD₄⁺、CD₄⁺ /CD₈⁺均高于对照组,IL-4、IL-6、TNF-α、CD₈⁺均低于对照组(P<0.05)。治疗后观察组的血清IgA和IgG水平明显高于对照组(P<0.05),而血清IgM水平差异无统计学意义(P>0.05)。两组不良反应情况比较无统计学差异(P>0.05)。结论: 滋阴益肾法可显著降低ITP患者血清IL-4、IL-6等因子水平,提高患者免疫能力。     

红景天苷通过TLR4调控DC提高T细胞对肺癌3LL细胞的杀伤力

目的：探讨红景天苷（salidroside，SAL）对树突状细胞（dendritic cell，DC）表型及细胞毒性T细胞（cytotoxic T lympho‐cyte，CTL）抗肿瘤能力的影响。方法：选用Lewis肺癌细胞株3LL、野生型C57BL/6和TLR4-/-C57BL/6小鼠，获取小鼠骨髓来源的DC前体细胞，经过培养分化成未成熟DC，收获第6天的DC，经磁珠分选后获得纯度较高的CD11c+DC。将细胞分成PBS组、SAL组和脂多糖（lipopolysaccharide，LPS）组，培养48 h后用流式细胞术检测SAL体外对DC表面分子、吞噬功能、TLR4通路和对T细胞杀伤能力的影响。结果：与 PBS 组比较，SAL组DC的表面分子CD80、CD86、MHC Ⅱ表达水平显著升高（均 P<0.05）、吞噬功能显著下降（P<0.05）、TLR4 表达水平显著升高（P<0.01）；与野生型组比较，TLR4-/-组DC经SAL或LPS处理后，其表面分子CD80、CD86、MHC Ⅱ的表达水平显著降低（均P<0.05）；与PBS组比较，SAL组刺激活化的CTL对肺癌3LL细胞的杀伤效应显著升高（P<0.05）。结论：SAL可以通过调控TLR4诱导DC成熟，从而提高T细胞的杀伤能力     

Vasoactive Intestinal Peptide Immunoregulatory Role at the Periapex: Associative and Mechanistic Evidences from Human and Experimental Periapical Lesions

IntroductionThe balance between the host proinflammatory immune response and the counteracting anti-inflammatory and reparative responses supposedly determine the outcome of periapical lesions. In this scenario, the vasoactive intestinal peptide (VIP) may exert a protective role because of its prominent immunoregulatory capacity. In this study, we investigated (in a cause-and-effect manner) the potential involvement of VIP in the development of human and experimental periapical lesions.MethodsPeriapical granulomas (n = 124) and control samples (n = 48) were comparatively assessed for VIP and multiple immunologic/activity marker expression through real-time polymerase chain reaction. Experimental periapical lesions (C57Bl/6 wild-type mice) were evaluated regarding endogenous VIP expression correlation with lesion development and the effect of recombinant VIP therapy in lesion outcome. CCR4KO and IL4KO strains and anti-glucocorticoid-induced TNFR-related protein inhibition were used to test the involvement of Treg and Th2 cells in VIP-mediated effects.ResultsVIP expression was more prevalent in periapical granulomas than in controls, presenting a positive association with immunoregulatory factors and an inverse association/correlation with proinflammatory mediators and the receptor activator of nuclear factor kappa B ligand/osteoprotegerin ratio. Endogenous VIP expression up-regulation was temporally associated with lesion immunoregulation and a decline of bone loss. VIP therapy in mice prompted the arrest of lesion development, being associated with an anti-inflammatory and proreparative response that limits the proinflammatory, Th1, Th17, and osteoclastogenic response in the periapex. The VIP protective effect was dependent of Treg migration and activity and independent of interleukin 4.ConclusionsOur results show that VIP overexpression in human and experimental periapical lesions is associated with lesion inactivity and that VIP therapy results in the attenuation of experimental lesion progression associated with the immunosuppressive response involving Treg cells.     

超顺磁性氧化铁标记大鼠骨髓基质细胞经门静脉移植MRI活体示踪的研究

目的观察1．5T场强MRI联合动物专用线圈是否可以活体示踪经门静脉移植的纳米级超顺磁性氧化铁颗粒标记的骨髓基质细胞（bone marrow stromal cells BMSCs），为介人性门静脉骨髓基质细胞移植治疗终末期肝脏疾病的研究提供进一步的依据。方法供体大鼠5只，梯度密度离心分离BMSCs，纳米级超顺磁性氧化铁颗粒和脂质体转染BMSCs，体外经普鲁士蓝染色和HE染色确定细胞标记率。受体大鼠15只，分为5组，分别为对照组和纳米级超顺磁性氧化铁颗粒标记的骨髓基质细胞经门静脉移植人正常大鼠肝脏后2h、3d、7d及2周组。1．5T场强MRI联合动物专用线圈行T1W、T2W和T2＊序列扫描，观察肝脏信号改变情况，与对照组比较，并且与组织切片对照。结果纳米级超顺磁性氧化铁颗粒和脂质体转染BMSCs，细胞标记率〉95％。经门静脉移植人正常大鼠肝脏后，T2＊序列扫描显示经标记的BMSCs在肝内显示弥漫性的结节性低信号影，移植后2h到2周均可见到细胞在受体肝脏内存在，组织学切片显示信号缺失部位与铁颗粒标记细胞相一致。结论纳米级超顺磁性铁氧体颗粒标记的大鼠BMSCs经门静脉移植后可以通过1、5T场强行MRI活体示踪，为临床干细胞移植的应用提供可行的示踪方法。     

雷帕霉素对内皮祖细胞数量与功能的影响

目的观察雷帕霉素对外周血内皮祖细胞（EPCs）数量与功能的影响。方法采用密度梯度离心法从外周血获得单个核细胞，将其接种在人纤维连接蛋白包被的培养板上，培养7天后收集贴壁细胞，加入不同浓度（1.0、2．0、5．0ug／m^3）雷帕霉素分别培养6、12、24、48h。激光共聚焦显微镜鉴定，FITC-UEA-I和Dil-acLDL双染色阳性细胞为正在分化的EPCs，流式细胞仪检测其表面标志以进一步鉴定EPCs，并在倒置荧光显微镜下计数。然后分别采用MTT比色法、改良的Boyden小室、黏附能力测定实验和体外血管生成试剂盒来观察EPCs的增殖能力、迁移能力、黏附能力和体外血管形成能力。结果EPCs数量随雷帕霉素浓度与作用时问增加而减少，其增殖能力、迁移能力、黏附能力和体外血管形成能力亦随雷帕霉素浓度与作用时间增加而降低。结论雷帕霉素降低EPCs的数量、增殖能力、迁移能力、黏附能力和体外血管形成能力，并呈浓度和时间依赖性。     

人间充质干细胞免疫原性研究

目的探讨人间充质干细胞(hMSCs)特性及免疫原性,为进一步研究hMSCs移植特性提供实验依据。方法免疫组化方法鉴定hMSCs表面HLA-ABC、HLA-DR、CD80、CD86分子;流式细胞术检测其含量;RT-PCR检测HLA-ABC、HLA-DRmRNA基因片断;外周血淋巴细胞杀伤试验及 CCK-8比色法规察淋巴细胞增殖反应;将表达绿色荧光蛋白(GFP)的DNA复合物导入hMSCs进行大鼠脑内移植,观察hMSCs在脑内的存活情况。结果 hMSCs表面少量表达HLA-ABC分子,不表达 HLA-DR、CD80、CD86分子;有少量HLA-ABC mRNA基因片断存在,未发现HLA-DR mRNA基因片断;外周血淋巴细胞杀伤试验没有发现淋巴细胞增殖反应;大鼠脑内移植hMSCs一个月后仍可见有细胞存活。结论 hMSCs具有较弱的免疫原性。