Deoxynivalenol induces apoptosis in PC12 cells via the mitochondrial pathway

Deoxynivalenol (DON) has broad toxicity in animals and humans. In this study the impact of DON treatment on apoptotic pathways in PC12 cells was determined. The effects of DON were evaluated on (i) typical indicators of apoptosis, including cellular morphology, cell activity, lactate dehydrogenase (LDH) release, and apoptosis ratio in PC12 cells, and on (ii) the expression of key genes and proteins related to apoptosis, including Bcl-2, Bax, Bid, cytochrome C (Cyt C), apoptosis inducing factor (AIF), cleaved-Caspase9, and cleaved-Caspase3. DON treatment inhibited proliferation of PC12 cells, induced significant morphological changes and apoptosis, promoted the release of Cyt C and AIF from the mitochondria, and increased the activities of cleaved-Caspase9 and cleaved-Caspase3. Bcl-2 expression decreased with increasing DON concentrations, in contrast to Bax and Bid, which were increased with increasing DON concentration. These data demonstrate that DON induces apoptosis in PC12 cells through the mitochondrial apoptosis pathway.     

Novel lipopeptides of ESAT-6 induce strong protective immunity against Mycobacterium tuberculosis: Routes of immunization and TLR agonists critically impact vaccine’s efficacy

Mycobacterium tuberculosis (Mtb), the bacterial cause of tuberculosis, is a leading infectious agent worldwide. The development of a new vaccine against Mtb is essential to control global spread of tuberculosis, since the current vaccine BCG is not very effective and antibiotic resistance is a serious, burgeoning problem. ESAT-6 is a secreted protein of Mtb, which is absent in BCG but has been implicated in inducing protective immunity against Mtb. Peptide based subunit vaccines are attractive due to their safety and high specificity in eliciting immune responses, but small synthetic peptides are usually not very immunogenic. We have designed a novel subunit vaccine for Mtb by using simple lipid (palmitic acid) modified derivatives of peptides from ESAT-6 protein corresponding to dominant human T cell epitopes and examined their ability to stimulate protective immunity against Mtb by intranasal and subcutaneous immunization in mice. We also investigated how individual TLR agonists as adjuvants (PolyI:C, MPL and GDQ) contribute to enhancing the induced immune responses and resulting protective efficacy of our vaccine. We observed that single C-terminal palmitoyl-lysine modified lipopeptides derived from ESAT-6 induce significant cellular immune responses on their own upon mucosal and subcutaneous immunizations. Intriguingly, a combination of immunogenic lipopeptides of ESAT-6 antigen exhibited local (pulmonary) and systemic immune responses along with efficient protective efficacy when administered intranasally or subcutaneously. Surprisingly, combination of ESAT-6 derived lipopeptides with a TLR-4 agonist (MPL) enhanced protection, whereas TLR-3 (Poly I:C) and TLR-7/8 agonists (gardiquimod, GDQ) led to reduced protection associated with specific local and systemic immune modulation. Our studies demonstrate the potential of ESAT-6 derived lipopeptides as a promising vaccine candidate against Mtb, and emphasize that selection of adjuvant is critical for the success of vaccines. These findings demonstrate the promise of synthetic lipopeptides as the basis of a subunit vaccine for TB.     

Influenza vaccination and the endurance against air pollution among elderly with acute coronary syndrome

ObjectiveAir pollution, weather condition and influenza are known risk factors of acute coronary syndrome (ACS) among elderly people. The influenza vaccine (IV) has been shown to reduce major cardiovascular events. The purpose of this study was to compare resistance to air pollution and weather factors causing ACS between vaccinated and less-vaccinated elderly people.MethodsA case–crossover design was applied to 1835 elderly ACS patients who were obtained from the 1-million sample of Taiwan National Health Insurance Research Data with inclusion criteria: (1) the first diagnosis of ACS was in cold season and at age 68 or more, (2) had received the free IV program at least once during the period 3 years before the ACS. They were stratified into two groups: 707 had received flu vaccinations for all the 3 years and the remaining 1128 had not. The measurements of air pollutants, temperature, and humidity corresponding to each of the 3 days prior to the ACS diagnosis date were retrieved from the data banks of the Taiwan Environmental Protection Administration and Central Weather Bureau.FindingsIncreases in air pollution concentrations of CO, NO₂, PM₁₀ or PM_2.5 and decreases in temperature significantly influenced the risk of ACS for the non-continuously vaccinated elderly population; however, less significant effects were observed for the continuously vaccinated population.ConclusionConsecutive influenza vaccination may potentially offer resistance against the detrimental effects of air pollution and changes in temperature in frail elderly adults with ACS. Future studies are needed to directly assess the interaction effect between the vaccination and environmental factors on ACS.     

N-myc下游调节基因家族成员3在胃癌细胞增殖和侵袭中的作用

目的探讨N-myc下游调节基因家族成员3(NDRG3)对胃癌细胞生物学行为的影响及其机制。方法实验分NDRG3敲减组和对照组,AGS-NDRG3小发夹状RNA(shRNA)组采用shRNA技术干扰AGS细胞中NDRG3表达,同时设置AGS-Vector对照组转染空白对照病毒;通过反转录-聚合酶链反应(RT-PCR)和蛋白质印迹法(Western blot)检测两组细胞中NDRG3 mRNA和蛋白表达以检查AGS-NDRG3 shRNA组中NDRG3敲减效果,利用细胞计数试剂盒(CCK-8)法和Transwell实验分别检测两组细胞中细胞增殖和侵袭能力,利用流式细胞仪分析两组细胞中细胞周期分布情况,并通过Western blot检测敲减两组细胞中细胞核增殖抗原(Ki-67)和p53蛋白表达水平,组间比较采用单因素方差分析。结果AGS-NDRG3 shRNA组NDRG3 mRNA和蛋白表达水平均显著低于对照组(NDRG3 mRNA,0.220±0.035比1.020±0.078,t=14.713,P<0.01;NDRG3蛋白,0.140±0.018比0.820±0.025,t=7.892,P<0.01),差异均有统计学意义。CCK-8实验结果显示,在培养24、48、72 h后,AGS-NDRG3 shRNA组细胞的增殖水平(0.388±0.025、0.576±0.044、0.873±0.051)明显低于对照组(0.457±0.033、0.674±0.047、1.125±0.062),差异均有统计学意义(t=4.983、5.852、8.082,P<0.01);Transwell迁移实验结果表明,AGS-NDRG3 shRNA组侵袭穿过Transwell小室膜的细胞数[(474.5±27.6)个]明显低于对照组[(1127.0±48.8)个],差异有统计学意义(t=12.380,P<0.01);细胞周期分析显示,敲减NDRG3表达的AGS细胞周期阻滞于S期,其S期占49.33%,对照组S期占30.29%(t=4.634,P<0.01),差异均有统计学意义;Western blot检测结果显示,敲减NDRG3表达后AGS细胞中Ki-67蛋白表达低于对照组(0.380±0.021比0.860±0.036,t=5.163,P<0.01)、野生型p53蛋白表达高于对照组(0.720±0.018比0.160±0.013,t=11.354,P<0.01),差异均有统计学意义。结论NDRG3可能通过调控p53通路促进AGS细胞增殖及侵袭能力。     

组蛋白去甲基化酶含有Jumonji结构域的蛋白质2D在胃癌组织的表达及其临床意义

目的观察含有Jumonji结构域的蛋白质2D(JMJD2D)在胃癌组织的表达并探讨其临床意义。方法收集2013年1月至2014年12月期间来自中国科学院大学附属肿瘤医院(浙江省肿瘤医院)手术治疗并经病理诊断证实的133例胃腺癌标本。采用免疫组织化学法检测133例胃癌组织及其配对的癌旁正常组织中JMJD2D的表达,应用SPSS-22统计软件分析其临床意义及与预后的关系,采用比例风险回归模型(proportional hazards model,Cox模型)多因素回归分析JMJD2D蛋白表达及其他病理参数对胃癌患者预后的预测价值。结果胃癌组织中JMJD2D的高表达率为75.9%(101/133),显著高于癌旁正常胃组织(高表达率2.3%,3/133,χ²=64.821,P<0.01),差异有统计学意义。肿瘤组织中JMJD2D高表达与患者幽门螺杆菌感染状态(χ²=22.163,P<0.01)、肿瘤分化程度(χ²=7.022,P<0.05)、浸润深度(χ²=5.061,P<0.05)、淋巴结转移状态(χ²=14.123,P<0.01)、临床TNM分期(χ²=23.194,P<0.01)显著相关,而与患者性别、肿瘤诊断时年龄、肿瘤部位和大小无相关(χ²=0.072、1.451、2.562、1.383,P值均>0.05)。普兰-迈耶(Kaplan-Meier)生存分析显示,JMJD2D高表达的胃癌患者与正常/低表达患者中位生存时间分别为34个月和65个月,两者差异有统计学意义(P<0.05)。比例风险回归模型(proportional hazards model,Cox模型)多因素回归分析表明JMJD2D高表达是胃癌患者独立预后因素[危险比(HR)=2.38,P<0.01]。结论JMJD2D在胃癌组织中高表达,且与胃癌进展及患者预后显著相关。     

Poly I:C primes the suppressive function of human palatine tonsil-derived MSCs against Th17 differentiation by increasing PD-L1 expression

It has been established that mesenchymal stem cells (MSCs) can have a suppressive effect on T cells, yet much remains unknown about the underlying mechanisms that support this effect. The T cell co-stimulatory pathway involving the programmed death-1 (PD-1) receptor and its ligand PD-L1 regulates T cell activation, tolerance, and subsequent immune-mediated tissue damage. In this study, human palatine tonsil-derived MSCs (T-MSCs) constitutively expressed PD-L1 and exhibited a suppressive activity that specifically targeted murine Th17 differentiation. Additionally, polyinosinic–polycytidylic acid (poly I:C), a Toll-like receptor 3 (TLR3) ligand, increased PD-L1 expression on T-MSCs. The elevated PD-L1 levels enhanced the suppressive functions of T-MSCs on Th17 differentiation. Therefore, pre-stimulation of T-MSCs with poly I:C may serve as an effective therapeutic priming step for modulating Th17-dominant immune responses.     

Immune response to hepatitis B vaccination among people with inflammatory bowel diseases: A systematic review and meta-analysis

IntroductionThe response rate to hepatitis B virus (HBV) vaccination in patients with inflammatory bowel disease (IBD) is low and varies markedly. We performed a systematic review and meta-analysis to determine the response rate to HBV vaccination and identified the factors predictive of an immune response.MethodsWe searched PubMed, Cochrane Library, and Embase databases, and reviewed the titles and abstracts of studies on the efficacy of HBV vaccination in IBD patients performed through July 2016. Anti-HBs levels > 10 IU/L was considered to be an effective immune response. The primary outcome measure was the response rate to HBV vaccination after series completion, and the secondary outcome was identification of factors at baseline predictive of an immune response.ResultsThirteen studies including 1688 patients were eligible for inclusion. Based on a random-effects model, the pooled rate of a response to HBV vaccination among patients with IBD was 61% (95% confidence interval [CI]: 53–69). Young age (mean difference [MD]: −5.7; 95% CI: −8.46, −2.95) and vaccination during disease remission (relative risk [RR]: 1.62; 95% CI: 1.15–2.29) were associated with a positive response to HBV vaccination. In addition, no immunosuppressive therapy was predictive of an immune response compared to immunomodulatory (RR: 1.33; 95% CI: 1.08–1.63) or anti-tumor necrosis factor-α (anti-TNF-α) (RR: 1.57; 95% CI: 1.19–2.08) therapy.ConclusionsBased on this meta-analysis, only three of five IBD patients will show a serological response to HBV vaccination. Vaccination should be performed at the time of IBD diagnosis, during disease remission, or before starting immunosuppressive therapy.