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71.
Steffanie Sabbaj Michael F. Para Robert J. Fass Patrick W. Adams Charles G. Orosz Caroline C. Whitacre 《Journal of clinical immunology》1992,12(3):216-224
The lymphocyte proliferative response to recall antigens is lost following HIV infection. We sought to devise a means by which the functional immune status of persons in the early stages of HIV infection could be monitored quantitatively. The response to tetanus toxoid was examined in 45 HIV-infected individuals and 11 controls using conventional lymphocyte proliferative assays concurrently with limiting dilution analysis utilizing the secretion of interleukin-2 as the measure of a response. Our data show that the limiting dilution analysis detects tetanus toxoid-reactive T cells in 80% of those tested, as compared to only 44% by proliferation. However, the frequency of tetanus-reactive T cells in HIV-infected individuals (median frequency = 1/59,156) is decrease five-fold as compared to seronegative controls (median frequency = 1/11,599). Longitudinal studies demonstrated a time-dependent decrease in the frequency of tetanus-specific T cell responses in the HIV-infected individuals. Thus, the limiting dilution analysis is a quantitative approach for detecting antigen-specific T cells in HIV-infected individuals, and may be used to monitor changes in T cell function in HIV infection. 相似文献
72.
The prebiotic effect of high β-glucan barley (HGB) flour on the innate immune system of high-fat model mice was investigated. C57BL/6J male mice were fed a high-fat diet supplemented with HGB flour for 90 days. Secretory immunoglobulin A (sIgA) in the cecum and serum were analyzed by enzyme-linked immunosorbent assays (ELISA). Real-time PCR was used to determine mRNA expression levels of pro- and anti-inflammatory cytokines such as interleukin (IL)-10 and IL-6 in the ileum as well as the composition of the microbiota in the cecum. Concentrations of short-chain fatty acids (SCFAs) and organic acids were analyzed by GC/MS. Concentrations of sIgA in the cecum and serum were increased in the HGB group compared to the control. Gene expression levels of IL-10 and polymeric immunoglobulin receptor (pIgR) significantly increased in the HGB group. HGB intake increased the bacterial count of microbiota, such as Bifidobacterium and Lactobacillus. Concentrations of propionate and lactate in the cecum were increased in the HGB group, and a positive correlation was found between these organic acids and the IL-10 expression level. Our findings showed that HGB flour enhanced immune function such as IgA secretion and IL-10 expression, even when the immune system was deteriorated by a high-fat diet. Moreover, we found that HGB flour modulated the gut microbiota, which increased the concentration of SCFAs, thereby stimulating the immune system. 相似文献
73.
Worldwide, the prevalence of allergies in young children, but also vitamin D deficiency during pregnancy and in newborns is rising. Vitamin D modulates the development and activity of the immune system and a low vitamin D status during pregnancy and in early life might be associated with an increased risk to develop an allergy during early childhood. This review studies the effects of vitamin D during gestation and early life, on allergy susceptibility in infants. The bioactive form of vitamin D, 1,25(OH)2D, inhibits maturation and results in immature dendritic cells that cause a decreased differentiation of naive T cells into effector T cells. Nevertheless, the development of regulatory T cells and the production of interleukin-10 was increased. Consequently, a more tolerogenic immune response developed against antigens. Secondly, binding of 1,25(OH)2D to epithelial cells induces the expression of tight junction proteins resulting in enhanced epithelial barrier function. Thirdly, 1,25(OH)2D increased the expression of anti-microbial peptides by epithelial cells that also promoted the defense mechanism against pathogens, by preventing an invasive penetration of pathogens. Immune intervention by vitamin D supplementation can mitigate the disease burden from asthma and allergy. In conclusion, our review indicates that a sufficient vitamin D status during gestation and early life can lower the susceptibility to develop an allergy in infants although there remains a need for more causal evidence. 相似文献
74.
75.
弓形虫主要表膜P30抗原的免疫保护作用研究 总被引:2,自引:0,他引:2
目的 研究弓形虫主要表膜P30抗原免疫小鼠所诱导的免疫性保护作用及免疫保护机制。方法 将单克隆抗体免疫亲和层析分离纯化的P30抗原免疫C57BL/6纯系小鼠,然后用弓形虫RH株速殖子和Fukaya株包衰攻击感染,观察P30抗原免疫对急性弓形虫感染鼠死亡时间及慢性感染鼠脑内包囊形成的影响,同时对感染后不同时间鼠血清特异性抗体水平、IL-2及IFN-r细胞因子水平和脾T淋巴细胞亚群动态变化进行了测试分析。结果 显示P30抗原免疫可在一定程度上延长感染小鼠的存活时间,减少脑内包囊的形成数量,增强小鼠抵抗急慢性弓形虫感染的能力。在感染后不同时期免疫鼠血清中特异性抗休还清瘃IFN-r、IL-2水平均高于同期对照鼠,而且免疫鼠脾CD4^ t CD8^ T淋纠细胞尤其是CD8^ 细胞的数量在感染早期升高较快,至感染后4周达高峰,两者的比值随感染时间的延长而逐渐下降。结论 P30抗原免疫对感染小鼠具有明显的保护作用,是细胞免疫和体液免疫共同作用的结果,尤其是细胞免疫可能发挥着更为重要的作用。 相似文献
76.
目的 :探讨血栓闭塞性脉管炎 (TAO)发病机制。方法 :利用透射电镜观察 9例 TAO患者血管中膜免疫复合物沉积与分布。结果 :在 4例 TAO患者血管中膜平滑肌细胞内和平滑肌细胞间观察到高电子致密度的免疫复合物沉积 ,同时还观察到与免疫复合物沉积与损伤相关的淋巴细胞、巨噬细胞、中性粒细胞。结论 :免疫复合物在血管壁沉积可能与 TAO发病有密切关系 相似文献
77.
目的 研究肉苁蓉总苷 (GCs)对 6 0 Co损伤小鼠免疫功能及 30 d存活率的影响。方法 小鼠在不同剂量6 0 Coγ射线照射前后 ,均服以 GCs,观察辐射及 GCs对其免疫功能的改变。结果 6 0 Co照射剂量为 2 ,4及 7Gy时 ,可造成小鼠体液免疫、细胞免疫功能和非特异性免疫功能及 30 d存活率下降 (P<0 .0 5或 P<0 .0 1) ;GCs(31.2 5 ,6 2 .5 ,12 5 m g/ kg)组可促进上述各指标的恢复 ,对 6 0 Co损伤小鼠的抗体产生、外周血 T淋巴细胞数目、迟发型超敏反应、腹腔巨噬细胞的吞噬功能均有明显保护作用 (P<0 .0 1或 P<0 .0 5 ) ;且能提高受照小鼠的脾指数、胸腺指数及 30 d存活率 (P<0 .0 1或 P<0 .0 5 )。结论 GCs对辐射损伤小鼠的免疫功能具有较强防护作用 相似文献
78.
79.
《中医科学杂志(英文)》2023,10(1):3-9
Inflammation-mediated carcinogenesis develops in the context of chronic inflammation and is a significant cause of cancer within the digestive system. In the chronic inflammation microenvironment, the metabolic activity of tissue cells undergoes extensive changes, which interfere with the normal function of immune cells. Dysregulation of cell metabolism and immune function has been identified as a key factor contributing to inflammation-mediated carcinogenesis within the major digestive organs, such as the stomach, liver, and colorectum. This metabolic–immune imbalance also corresponds to traditional Chinese medicine (TCM) theories of “yin-yang disharmony” and “disharmony between Ying-nutrients and Wei-defense.” The metabolic–immune imbalance has also been regarded as the key factor supporting “treatment of different diseases with the same method,” in which the same approach is adopted in the treatment of different conditions. In the TCM treatment process, it is necessary to first identify TCM patterns and then apply the corresponding TCM to correct the dysregulated metabolic and immune function, thereby blocking the progression from inflammation to malignancy. Our study findings deepen the TCM understanding of metabolic–immune dysregulation and the relationship between metabolic–immune dysregulation, pattern identification, and treatment method. They also provide new insights for the treatment of inflammation-mediated carcinogenesis in major digestive organs and help us further explore the scientific connotation of the TCM strategy of “treating different diseases with the same method. 相似文献
80.
目的 应用生物信息学技术,从免疫炎症角度探索严重急性呼吸综合征冠状病毒-2(severe acute respiratory syndrome coronavirus-2,SARS-CoV-2)感染诱导动脉粥样硬化(atherosclerosis,AS)进展的核心靶点及重要通路,进而预测潜在防治中药。方法 从基因表达数据库(Gene Expression Omnibus,GEO)中获取新型冠状病毒肺炎患者和动脉粥样硬化患者芯片数据,利用“limmar”包及“Venn”包筛选2种疾病的共同差异表达基因(differentially expressed genes,DEGs),对共同DEGs进行基因本体论(gene ontology,GO)和京都基因与基因组百科全书(Kyoto encyclopedia of genes and genomes,KEGG)分析,注释其功能及重要通路。对2组基因集进行免疫细胞和免疫功能打分,评估免疫细胞浸润水平。利用STRING数据库,构建蛋白-蛋白互作(protein-protein interaction,PPI)网络;通过Cytoscape的CytoH... 相似文献