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61.
为了解动物在注射口蹄疫灭活疫苗后机体免疫状态的变化情况,本试验选取口蹄疫阴性猪进行疫苗免疫,利用流式细胞术检测方法来测定外周血中免疫细胞亚群的变化。结果显示,树突状细胞在免疫后能够快速产生应答,在24 h内其含量出现明显升高;B细胞和Th细胞含量在免疫后第10天都出现了明显升高,且两者之间的变化存在着高度相关性,而抗体水平的变化情况与这两种细胞含量的变化也高度相关;细胞毒性T细胞含量在免疫后也出现升高。这说明灭活疫苗免疫动物后不仅可以激活机体的体液免疫应答反应,产生高水平抗体,发挥免疫保护作用,更重要的是能够在短时间内激发机体的固有免疫应答,同时能够激活细胞免疫应答,全方位发挥免疫保护作用。  相似文献   
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63.
目的研究急性化脓性扁桃体炎患者不同证候层次外周血Th1/Th2漂移变化。方法通过流式细胞检测技术,对急性化脓性扁桃体炎患者卫分证、气分证、营分证和正常人外周血Th1/Th2细胞进行检测,采用ELISA法测定血清细胞因子IL-4和IFN-γ水平,并比较IFN-γ/IL-4比值。结果与正常对照组比较,急性化脓性扁桃体炎卫分证组Th1、IFN-γ、Th1/Th2、IFN-γ/IL-4比值显著升高,差异有统计学意义(P<0.05);气分证组Th1、Th2、IFN-γ、IL-4明显升高,差异有统计学意义(P<0.05~0.01);营分证组Th1、Th2、IFN-γ、IL-4继续明显升高,Th1/Th2比值却明显降低,差异有统计学意义(P<0.05~0.01)。与卫分证组比较,气分证组Th1、Th2、IFN-γ、IL-4显著升高,Th1/Th2、IFN-γ/IL-4比值明显降低,差异有统计学意义(P<0.05~0.01);营分证组Th2、IL-4继续明显升高,Th1/Th2、IFN-γ/IL-4比值明显降低,差异有统计学意义(P<0.01)。与气分证组比较,营分证组Th1、IFN-γ水平、Th1/Th2、IFN-γ/IL-4比值显著降低,Th2、IL-4显著升高,差异有统计学意义(P<0.05~0.01)。结论急性化脓性扁桃体炎卫分证、气分证、营分证证候层次变化与Th1/Th2漂移存在相关性。  相似文献   
64.
WANG Lu  JIANG Tao 《园艺学报》2016,32(2):273-277
AIM: To observed the correlation between Th17 cell level and the symptom severity and prognostic factors of chronic obstructive pulmonary disease (COPD), and to explore the clinical application value of Th17 cell level in assessing the prognosis of patients with COPD. METHODS: The patients with diagnosed COPD (n=110) in our hospital during May 2013 to December 2014, and 40 healthy subjects were enrolled in the study. According to the Global Initiative for Chronic Obstructive Lung Disease (GOLD), the COPD patients were divided into group A (low risk, less symptoms), group B (low risk, more symptoms), group C (high risk, less symptoms) and group D (high risk, more symptoms), which were given inhaled corticosteroid/long-acting β2 agonist or corticosteroid/long-acting β2 agonist+long-acting antimuscarinic agent treatment for 3 months. The proportion of Th17 cells, cytokines (IL-17 and IL-6), the COPD assessment test (CAT) score, age, body mass index, pulmonary function and the times of acute exacerbation of COPD in previous 1 year were observed before and after treatment. The correlation analysis between the level of Th17 cells and other clinical characteristics was performed. RESULTS: Th17 cell, IL-17 and IL-6 levels in COPD group were significantly higher than those in control group (P < 0.05). With the increase in the severity of COPD symptoms, Th17 cells, cytokines (IL-17 and IL-6) and CAT score in groups B and D were significantly higher than those in groups A and C (P < 0.05). The univariate analysis showed that the levels of Th17 cells in groups B and D before treatment were positively correlated with the CAT score (P < 0.05), which were negatively correlated with FEV1 , FEV1% Pred, FVC and FVC% Pred. The levels of Th17 cells were not correlated with the CAT score, FEV1, FEV1% Pred, FVC and FVC% Pred in groups A and C. The levels of Th17 cells after treatment were positively correlated with the CAT score, which were negatively correlated with FEV1 , FEV1% Pred, FVC and FVC% Pred (P < 0.05). CONCLUSION: The peripheral Th17 cell level has a good correlation with IL-17, IL-6, CAT score and pulmonary function in COPD patients, suggesting a potential value to predict the symptom severity and prognosis of COPD.  相似文献   
65.
为探究重组鸡白细胞介素-6/2融合蛋白(rChIL-6-Linker-ChIL-2,重组融合蛋白)对新城疫病毒(NDV)活疫苗(LaSota株)的免疫增强作用,本研究将90只SPF鸡随机分为6组,分别为PBS对照组、NDV弱毒苗对照组、rChIL-6-Linker-ChIL-2免疫增强组、rChIL-6蛋白免疫增强组、rChIL-2蛋白免疫增强组及rChIL-6+rChIL-2混合蛋白免疫增强组,将鸡白细胞介素重组融合蛋白水剂与LaSota株联合接种于SPF鸡,分别采用MTS法、流式细胞术、ELISA和HA/HI法检测接种前后不同时间各组鸡外周血及脾淋巴细胞增殖活性、鸡外周血中CD3+CD4+/CD3+CD8+T淋巴细胞的百分含量、血清中Th1/Th2型细胞因子表达水平及免疫抗体水平等指标。结果显示,接种后7~21d时,与NDV弱毒苗对照组相比,同时接种重组融合蛋白组鸡淋巴细胞增殖活性、外周血CD3+CD4+/CD3+CD8+T淋巴细胞的百分含量比值及血清中重组鸡IL-4蛋白(rChIL-4)、ChIL-6、ChIL-2、重组鸡IFN-α蛋白(ChIFN-α)、ChIFN-γTh1/Th2型细胞因子表达水平明显提升;HI免疫抗体较NDV弱毒苗对照组提高了1.0~1.9个滴度,较单一rChIL-6、rChIL-2对照组分别提高了0.2~0.7、0.2~1.1个抗体滴度。综上所述,rChIL-6-Lin-ker-ChIL-2融合蛋白对NDV(LaSota株)活疫苗在鸡体内具有明显的免疫增强效果。  相似文献   
66.
T helper (Th) cells produce signature cytokine patterns, induced largely by intracellular versus extracellular pathogens that provide the cellular and molecular basis for counter regulatory expression of protective immunity during concurrent infections. The production of IL-12 and IFN-γ, for example, resulting from exposure to many bacterial, viral, and protozoan pathogens is responsible for Th1-derived protective responses that also can inhibit development of Th2-cells expressing IL-4-dependent immunity to extracellular helminth parasites and vice versa. In a similar manner, concurrent helminth infection alters optimal vaccine-induced responses in humans and livestock; however, the consequences of this condition have not been adequately studied especially in the context of a challenge infection following vaccination. Demands for new and effective vaccines to control chronic and emerging diseases, and the need for rapid deployment of vaccines for bio security concerns requires a systematic evaluation of confounding factors that limit vaccine efficacy. One common albeit overlooked confounder is the presence of gastrointestinal nematode parasites in populations of humans and livestock targeted for vaccination. This is particularly important in areas of the world were helminth infections are prevalent, but the interplay between parasites and emerging diseases that can be transmitted worldwide make this a global issue. In addition, it is not clear if the epidemic in allergic disease in industrialized countries substitutes for geohelminth infection to interfere with effective vaccination regimens. This presentation will focus on recent vaccination studies in mice experimentally infected with Heligmosomoides polygyrus to model the condition of gastrointestinal parasite infestation in mammalian populations targeted for vaccination. In addition, a large animal vaccination and challenge model against Mycoplasma hyopneumonia in swine exposed to Ascaris suum will provide a specific example of the need for further work in this area, and for controlled field studies to assess the impact of other similar scenarios.  相似文献   
67.
Immune imbalance of Treg/Th17 cells may contribute to recurrent implantation failure (RIF) during in vitro fertilization and embryo transfer (IVF-ET). In this study, we sought to determine the effect of intrauterine administration of mouse PBMCs prior to embryo implantation on endometrial receptivity and embryo implantation, and examine the underlying mechanism of Treg/Th17 cell balance following intrauterine administration of PBMCs. Pregnant mice were randomly divided into three groups: control group, embryo implantation dysfunction (EID) group, and EID with PBMCs group, and the number of embryo implantation sites was recorded during early pregnancy (Pd7.5). The balance of Treg/Th17 cells in the peripheral blood, spleen, and local implantation sites was detected during the peri-implantation period (Pd4.0) and early pregnancy (Pd7.5). The EID group demonstrated a significant decrease in the number of embryo implantation sites, while the EID with PBMCs group demonstrated higher number of embryo implantation sites compared to the EID group. The balance of Treg/Th17 cells in the peripheral blood and spleen tissues was not significantly different between the aforementioned groups. However, the local uterine ratio of the Treg/Th17 cells increased in the EID with PBMCs group compared to that in the EID group. Collectively, we found that intrauterine administration of PBMCs prior to embryo implantation effectively promotes embryo implantation rates. This may be attributed to the improvement in the local immune balance of Treg and Th17 cells compared with the overall immune balance.  相似文献   
68.
Caspase-associated recruitment domain-containing protein 9 (CARD9) deficiency is an autosomal-recessive primary immunodeficiency characterized by susceptibility to recurrent Candida infections, and its diagnosis and treatment is challenging. The present study aims to investigate the genetic characteristic and treatment strategy of a Chinese pediatric patient with CARD9 deficiency. In the present study, whole-exome sequencing (WES) was performed to screen the causal variants in a Chinese pediatric patient who exhibited an invasive Candida infection in the abdominal cavity and central nervous system. After the disease-causing gene being confirmed, the patient was treated with a combination of G-CSF and antifungal agents. DNA sequencing revealed a homozygous insertion mutation (c.819–820insG) in exon 6 of the CARD9 gene, which led to downstream amino acids conversion on codon 274 (p.D274fsX60). Th17 cell populations and cytokine levels showed decreased levels. The treatment regimen successfully resolved the patient’s symptoms, and he remained symptom-free after more than 1 year of follow-up. This study described an invasive Candida infection in a pediatric patient and WES identified an insertion variant of the CARD9 gene. A combination of G-CSF and antifungal agents was highly effective in treating the invasive fungal infection accompanied by CARD9-induced immunodeficiency.  相似文献   
69.
为了初步探讨绵羊痒螨巨噬细胞迁移抑制因子(PoMIF)对健康新西兰兔外周血单个核细胞(PBMC)中Th1/Th2和Th17/Treg细胞平衡的变化。采用RT-PCR从绵羊痒螨总RNA中扩增得到MIF全长基因,经原核表达、纯化重组PoMIF(rPoMIF)蛋白,并分析其氧化还原酶和互变异构酶活性。筛选与健康新西兰兔PBMC孵育的最佳rPoMIF浓度,且用最佳浓度rPoMIF(0.2 μg·mL-1)与PBMC共同孵育0、1、6、12、24、36 h后收集细胞,用荧光定量PCR检测其Th1/Th2/Th17/Treg细胞相对应的特征性转录因子T-bet/GATA-3/RORc/Foxp3和特征性细胞因子IFN-γ/IL-4/IL-17A/IL-10 mRNA表达变化。结果表明:PoMIF全长363 bp,rPoMIF大小为32 ku(含pET32a标签蛋白19 ku),且具有互变异构酶活性;rPoMIF刺激后PBMC中Th1细胞的T-betIFN-γ先下降后上升,Th2细胞的GATA-3和IL-4均呈下降趋势,且T-bet/GATA-3和IFN-γ/IL-4比值在12、24和36 h均升高;Th17细胞的RORc和IL-17A在各时间点下降,而Treg细胞的Foxp3和IL-10在各时间点升高,且RORc/Foxp3和IL-17A/IL-10比值在各时间点均变低。rPoMIF可造成家兔外周血单个核细胞的Th1/Th2和Th17/Treg平衡分别向Th1和Treg偏移。  相似文献   
70.
运用冷冻切片技术,用光学显微镜对阴香〔Cinnamomum burmannii(C.G.&Th.Nees)Bl.〕叶的解剖结构进行了观察研究。结果表明,阴香叶为典型的异面叶;上下表皮均由一层排列紧密形状不规则细胞组成,上表皮细胞外角质膜较厚;气孔主要分布在下表皮上,气孔类型为无规则型;叶肉组织不甚发达,具分泌腔,栅栏组织由1~2层排列疏松的柱状细胞组成,海绵组织有发达的胞间隙,横切面上栅栏组织厚度与海绵组织厚度之比为1∶1.6;主脉发达,为外韧维管束,具有厚壁细胞组成的维管束鞘,侧脉有发达的由厚壁细胞组成的维管束鞘延伸区。这些特征反映出阴香叶片结构与其生长环境之间的适应性关系。  相似文献   
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