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《Vaccine》2022,40(6):934-944
Respiratory Syncytial Virus (RSV) remains a leading cause of severe respiratory disease for which no licensed vaccine is available. We have previously described the derivation of an RSV Fusion protein (F) stabilized in its prefusion conformation (preF) as vaccine immunogen and demonstrated superior immunogenicity in naive mice of preF versus wild type RSV F protein, both as protein and when expressed from an Ad26 vaccine vector. Here we address the question if there are qualitative differences between the two vaccine platforms for induction of protective immunity. In naïve mice, both Ad26.RSV.preF and preF protein induced humoral responses, whereas cellular responses were only elicited by Ad26.RSV.preF. In RSV pre-exposed mice, a single dose of either vaccine induced cellular responses and strong humoral responses. Ad26-induced RSV-specific cellular immune responses were detected systemically and locally in the lungs. Both vaccines showed protective efficacy in the cotton rat model, but Ad26.RSV.preF conferred protection at lower virus neutralizing titers in comparison to RSV preF protein. Factors that may contribute to the protective capacity of Ad26.RSV.preF elicited immunity are the induced IgG2a antibodies that are able to engage Fcγ receptors mediating Antibody Dependent Cellular Cytotoxicity (ADCC), and the induction of systemic and lung resident RSV specific CD8 + T cells. These data demonstrate qualitative improvement of immune responses elicited by an adenoviral vector based vaccine encoding the RSV preF antigen compared to the subunit vaccine in small animal models which may inform RSV vaccine development.  相似文献   
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门桐林  李雪  袁秀敏  张璐 《癌症进展》2020,(6):563-566,613
目的探讨程序性死亡受体1(PD-1)和程序性死亡受体配体1(PD-L1)在非小细胞肺癌(NSCLC)组织中的表达情况及临床意义。方法选择150例NSCLC患者的NSCLC组织及其癌旁组织,采用实时荧光定量聚合酶链反应(PCR)检测两种组织中PD-1 mRNA和PD-L1 mRNA的相对表达量。采用免疫组织化学染色法检测NSCLC组织中PD-1和PD-L1的表达情况,分析PD-1和PD-L1表达情况与患者临床特征的关系。采用流式细胞术检测NSCLC组织和癌旁组织中CD4^+-PD-1、CD8^+-PD-1、CD14^+-PD-L1、CD68^+-PD-L1的表达水平。结果NSCLC组织中PD-1 mRNA和PD-L1 mRNA的相对表达量分别为(5.03±1.92)和(4.95±1.09),分别高于癌旁组织的(1.72±0.81)和(1.25±0.24),差异均有统计学意义(P﹤0.05)。TNM分期为Ⅲ~Ⅳ期、低分化、有淋巴结转移、有远处转移的NSCLC患者NSCLC组织中PD-1和PD-L1的高表达率均明显高于TNM分期为Ⅰ~Ⅱ期、高+中分化、无淋巴结转移、无远处转移的患者,差异均有统计学意义(P﹤0.01)。NSCLC组织中CD4^+-PD-1、CD8^+-PD-1、CD14^+-PD-L1、CD68^+-PD-L1的表达水平均明显高于癌旁组织,差异均有统计学意义(P﹤0.01)。结论PD-1和PD-L1在NSCLC组织中高表达,可能成为一种新的生物标志物,PD-1/PD-L1信号通路可能参与了NSCLC的免疫逃逸过程,对其逃逸机制进行研究可以为NSCLC患者的临床治疗提供新靶点。  相似文献   
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目的: 探讨人胃癌组织中乙酰肝素酶(HPA)、上皮标志物E-cadherin、间质标志物N-cadherin和vimentin蛋白的表达及其与人胃癌临床病理指标的关系,以及HPA与E-cadherin、N-cadherin、vimentin蛋白之间的关系。方法: 应用免疫组织化学方法检测91例人胃癌组织中HPA、E-cadherin、N-cadherin和vimentin蛋白表达情况;采用卡方检验,检测这几种蛋白阳性表达率与人胃癌不同病理指标的关系;同时采用Spearman等级相关分析HPA与E-cadherin、N-cadherin、vimentin蛋白之间的关系。结果: 人胃癌组织中HPA、E-cadherin、N-cadherin和vimentin蛋白阳性表达率为75.82%、51.65%、54.95%和23.08%。91例人胃癌组织中HPA、E-cadherin、N-cadherin和vimentin蛋白的阳性表达率与胃癌患者年龄、性别、胃癌大小均无明显相关(P > 0.05),而与人胃癌发生部位、分化程度和有无淋巴结转移、侵袭程度有关(P < 0.05)。HPA、N-cadherin和vimentin蛋白在贲门部阳性表达率明显高于胃体、幽门及胃窦胃癌;低分化者、有淋巴结转移者和胃癌侵袭深处这3种蛋白阳性表达率明显高于高分化者、无淋巴结转移者和胃癌起始部位;E-cadherin蛋白在幽门及胃窦部胃癌阳性表达率明显高于贲门和胃体胃癌;高中分化者、无淋巴结转移者明显高于低分化者和有淋巴结转移者。E-cadherin蛋白阳性表达率在侵袭深处明显低于起始部位。经Spearman等级相关分析显示,人胃癌组织中HPA与E-cadherin蛋白的阳性表达率呈负相关(r=-0.341,P < 0.05);而与N-cadherin(r=0.366,P < 0.05)和vimentin(r=0.284,P < 0.05)蛋白阳性表达率呈正相关。结论: 人胃癌组织中HPA、N-cadherin和vimentin蛋白在低分化者、有淋巴结转移者和胃癌侵袭深处高表达;E-cadherin蛋白在高中分化胃癌,无淋巴结转移者和起始部位高表达。HPA与N-cadherin、vimentin蛋白阳性表达率呈正相关,HPA与E-cadherin蛋白的阳性表达率呈负相关,可见HPA蛋白与间质标志物N-cadherin和vimentin蛋白表达增强有关,而与上皮标志物E-cadherin蛋白缺失或减少有关,因此HPA可能诱导人胃癌组织发生上皮间质转化。  相似文献   
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目的 探讨IgG4和C3在泪腺良性淋巴上皮病变发生发展中的作用。方法 收集2010年7月至2018年5月就诊于承德医学院附属医院眼科、解放军总医院眼科15例(15眼)泪腺良性淋巴上皮病变患者的泪腺肿物为试验组,10例(10眼)因其他疾病而行眶内容物摘除术的正常泪腺组织标本为对照组。采用HE染色法观察2组泪腺病理形态学变化及其组织病理学特点,采用免疫组织化学染色法检测2组泪腺组织中IgG4、C3的表达,并对二者表达相关性进行分析。结果 HE染色结果显示,对照组泪腺由正常腺泡及导管组成,导管上皮细胞排列整齐,细胞结构清晰,其间有少量的淋巴细胞;试验组泪腺组织中可见大量淋巴细胞、浆细胞浸润,淋巴滤泡形成,其间可见上皮-肌上皮岛结构改变,同时伴有不同程度纤维化。IgG4在试验组阳性表达面积为(30 934.80±16 057.17)像素,对照组阳性表达面积为(325.42±204.43)像素,试验组中明显高于对照组(t=-7.38,P=0.000);C3在试验组阳性表达面积为(43 169.49±33 206.60)像素,对照组阳性表达面积为(323.24±271.29)像素,试验组中明显高于对照组,差异有统计学意义(t=-5.00,P=0.000)。试验组中IgG4与C3表达无相关性(r=-0.137,P=0.671)。结论 泪腺良性淋巴上皮病变患者的泪腺发生了明确的病理改变,这可能与IgG4和C3在泪腺中的高表达有关。  相似文献   
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IntroductionRecent reports on gene expression profiling (GEP) show several genes associated with malignant progression of GIST. However, genes associated with malignant transformation have not been clarified. Here, we aimed to reveal distinct genes in aggressive malignant GIST, using comprehensive gene expression analysis.Materials and methodsWe investigated GEP obtained by microarrays for 43 gastric GISTs, which mostly harbored KIT and PDGFRA mutations and integrated clinicopathological risk information. RT-PCR and immunohistochemistry were performed for FZD7, a receptor of Wnt ligands.ResultsGEP divided 43 gastric GISTs into two clusters. A cluster included seven of eight high-risk GISTs (88%) in modified NIH classification and was defined as high-risk cluster; the other cluster was defined as low-risk cluster. The number of probes with over 3-fold changes between the two clusters was 1,177, in which probes corresponding to 16 oncogenes were included. Genes involved in the Wnt signaling pathway were the most abundant among the 16 oncogenes. Focusing on 73 Wnt signaling pathway genes of the 21,578 probes, 12 upregulated and 5 downregulated genes were found in the high-risk cluster. Major cascade genes promoting the Wnt/β-catenin signaling pathway, including WNT11, FZD family, and DVL2, were upregulated in the high-risk cluster. SNAI1, SNAI2, and BIRC5, which are activated by this pathway and increase cell proliferation, were also upregulated. These gene expression alterations were consistent in the positive direction of this pathway. GISTs in high-risk cluster strongly expressed FZD7.ConclusionWnt/β-catenin signaling pathway may play an important role in malignant transformation of indolent GIST.  相似文献   
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《Vaccine》2022,40(11):1594-1605
In addition to providing pathogen-specific immunity, vaccines can also confer nonspecific effects (NSEs) on mortality and morbidity unrelated to the targeted disease. Immunisation with live vaccines, such as the BCG vaccine, has generally been associated with significantly reduced all-cause infant mortality. In contrast, some inactivated vaccines, such as the diphtheria, tetanus, whole-cell pertussis (DTPw) vaccine, have been controversially associated with increased all-cause mortality especially in female infants in high-mortality settings. The NSEs associated with BCG have been attributed, in part, to the induction of trained immunity, an epigenetic and metabolic reprograming of innate immune cells, increasing their responsiveness to subsequent microbial encounters. Whether non-live vaccines such as DTPw induce trained immunity is currently poorly understood. Here, we report that immunisation of mice with DTPw induced a unique program of trained immunity in comparison to BCG immunised mice. Altered monocyte and DC cytokine responses were evident in DTPw immunised mice even months after vaccination. Furthermore, splenic cDCs from DTPw immunised mice had altered chromatin accessibility at loci involved in immunity and metabolism, suggesting that these changes were epigenetically mediated. Interestingly, changing the order in which the BCG and DTPw vaccines were co-administered to mice altered subsequent trained immune responses. Given these differences in trained immunity, we also assessed whether administration of these vaccines altered susceptibility to sepsis in two different mouse models. Immunisation with either BCG or a DTPw-containing vaccine prior to the induction of sepsis did not significantly alter survival. Further studies are now needed to more fully investigate the potential consequences of DTPw induced trained immunity in different contexts and to assess whether other non-live vaccines also induce similar changes.  相似文献   
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目的:观察糖尿病小鼠小肠绒毛杯状细胞分泌的黏原颗粒是否改变,为进一步研究糖尿病的消化系统并发症提供形态学基础。方法分别选取3,5,8,10月龄db/db糖尿病小鼠及相应年龄段的db/+m正常小鼠,每组6只,标本用4%多聚甲醛灌流固定后,从距Treitz韧带约10 cm处切下一段空肠,用PAS染色方法对小肠杯状细胞分泌的黏原颗粒进行观察。结果糖尿病组小肠绒毛易被破坏,糖尿病组中杯状细胞的分泌物比同月份正常对照组显著增加(P<0.05);糖尿病组中3月龄的杯状细胞分泌物最多,8月龄最少,并且8月龄分别与3月龄、5月龄比较均存在着显著差异(P<0.05);正常对照组随月龄增长无显著性差异(P>0.05)。结论糖尿病时杯状细胞分泌物增多可能对小肠绒毛有保护作用。  相似文献   
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