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11.
目的观察护卵汤配合补佳乐及安宫黄体酮对卵巢早衰(POF)模型小鼠卵巢Th17和Treg表达水平的影响。方法采用透明带多肽(PZP3)及弗氏完全佐剂(CFA)和弗氏不完全佐剂(IFA)建立POF模型小鼠,随机分为空白组、模型组、护卵汤+补佳乐+安宫黄体酮组(护补安组)、补佳乐+安宫黄体酮组(补安组)、护卵汤组,护卵汤分别给药对POF模型小鼠进行干预后,采用酶联免疫吸附(ELISA)法检测各组小鼠的血清促卵泡生成素(FSH)、雌二醇(E2)含量;逆转录-聚合酶链反应(RT-PCR)检测小鼠卵巢的Th17和Treg表达水平;光镜下观察各组卵巢组织形态学变化。结果与模型组比较,护补安组、补安组、护卵汤组对致衰小鼠有治疗作用,差异具有统计学意义(P<0.01);护补安组、补安组在降低小鼠血清FSH含量方面优于护卵汤组(P<0.05);但护卵汤组在降低小鼠卵巢Th17水平上优于补安组,差异具有统计学意义(P<0.05)。结论护卵汤配合补 佳乐及安宫黄体酮可通过降低小鼠卵巢Th17而升高小鼠卵巢Treg水平治疗卵 巢早衰模型小鼠,且在降低小鼠血FSH含量上优于单纯护卵汤组。  相似文献   
12.
The idea has been popular for a long time that Th1/Th2 imbalance is the major cause of many diseases. However, the Th1/Th2 paradigm has encountered increasing challenge since the discovery of a novel subset of Th cells, Th17. Th17 cells secrete a series of cytokines (IL-17A~F, IL-21 and IL-22), which is quite different from those produced by Th1 and Th2 cells. It is now generally accepted that Th17/IL-17A plays a pivotal role in autoimmune and host defense. Although first discovered in autoimmune diseases, emerging studies begin to explore the way in which Th17/IL-17A acts in chronic inflammatory airway diseases, such as asthma and chronic obstructive pulmanary disease. In this review, we will summarize the differentiation and function of Th17, and introduce the progress in the correlation between Th17/IL-17A and chronic inflammatory airway diseases. Further elucidating the mechanism of Th17/IL-17A-related pathophysiological changes will contribute to prevention and treatment of chronic inflammatory airway diseases.  相似文献   
13.
AIM: To investigate the balance of Treg/Th17 in synovium of collagen-induced arthritis (CIA) and the impact of tumor necrosis factor α(TNF-α) blockage therapy. METHODS: Rat CIA model was established by bovine II collagen injection. The pathological score was evaluated by HE staining and toluidine blue staining. The TNF-α level in plasma was measured by ELISA. The expression of Treg/Th17 in synovium was detected by double staining immunofluorescence. RESULTS: The plasma level of TNF-α in CIA group was significantly higher than that in control group and TNFR-Fc treatment group (P<0.01), whereas no significant difference was found between TNFR-Fc treatment group and control group (P>0.05). No significant difference between CIA group and control group in the ratio of CD4+Foxp3+Treg cells/CD4+ cells in synovium (23.12%±4.93% vs 24.66%±5.82%, P>0.05) was observed, whereas the ratio in TNFR-Fc treatment group was significantly increased(33.07%±5.14%). The ratio of CD4+RORγt+Th17 cells/CD4+ cells in CIA group was significantly higher than that in control group and TNFR-Fc treatment group (9.74%±2.23% vs 1.00%±0.59%, 5.63%±1.76%, P<0.01). CONCLUSION: Differentiation disturbance of Treg/Th17 exists in the synovium of CIA rats. TNFR-Fc may restore the balance of Treg/Th17 by inhibiting Th17 cell differentiation and inducing the production or accumulation of Treg.  相似文献   
14.
先天性免疫细胞由树突细胞、肥大细胞、巨噬细胞、嗜酸粒细胞和天然杀伤细胞组成。旋毛虫入侵机体后,这些先天性免疫细胞作为前沿免疫防御系统,首先快速发挥各自作用,并诱发更加有效的Th2型免疫应答,在保护机体免受重大损伤、抵制并排除旋毛虫方面起着必不可少的作用。论文详细综述了旋毛虫感染机体后,机体先天性免疫细胞的作用方式、作用机制以及相关免疫分子的研究进展。  相似文献   
15.
This study aimed to investigate the role of epithelial cells in regulating innate immunity in bovine oviduct epithelial cell (BOEC) culture. We studied the effect of Escherichia coli lipopolysaccharide (LPS) and its interaction with ovarian steroids, estradiol (E2) and progesterone (P4), and luteinizing hormone (LH) at concentrations observed during the preovulatory period on immune responses in BOEC culture. Immunohistochemistry of oviduct tissue showed intensive expression of Toll-like receptor-4 (TLR-4) and TLR-2 in epithelial cells. A dose of 10 ng/ml LPS stimulated TLR-4, cyclooxygenase-2 (COX-2), nuclear factor kappa B inhibitor A (NFKBIA), interleukin 1β (IL-1β) and tumor necrosis factor α (TNF-α) expression, indicating an early pro-inflammatory response. A dose of 100 ng/ml LPS did not induce expression of these genes but stimulated TLR-2, IL-10,IL-4 and microsomal prostaglandin E synthase-1 (mPGES-1) expression and PGE2 secretion, indicating an anti-inflammatory response. Ovarian steroids and LH completely block LPS (10 ng/ml)-induced TLR-4, IL-1β and TNF-α expression as well as LPS (100 ng/ml)-induced TLR-2 expression. Taken together, this study suggests the existence of an early signaling system to respond to infection in the BOEC. In addition, ovarian steroids and LH may play a critical role in inducing homeostasis and in controlling hyperactive pro-inflammatory responses detrimental to epithelial cells, sperm and the embryo.  相似文献   
16.
研究云南松松塔乙醇提取物(PEA)和碱水提取醇沉物(PED)对H22实体瘤小鼠的抑瘤作用。建立H22实体瘤小鼠模型,随机分组,灌胃给药,1次/d,给药10d。末次给药24h后,取血检测γ干扰素(IFN-γ)、白细胞介素-2(IL-2)、白细胞介素-4(IL-4)和白细胞介素-10(IL-10)含量;剥离肿瘤组织并称重,计算抑瘤率;检测肿瘤组织匀浆中环氧化酶-2(COX-2)和前列腺素E2(PGE2)含量;石蜡包埋HE染色观察肿瘤细胞病理组织学变化。结果显示,PEA和PED各剂量组小鼠平均肿瘤重量较模型组显著减小;最大抑瘤率分别达46.11%和58.05%。PEA和PED各剂量组小鼠外周血中IFN-γ和IL-2含量较模型组显著升高;IL-4和IL-10含量较模型组显著降低。PEA和PED各剂量组小鼠肿瘤组织中COX-2和PGE2含量较模型组显著减少;给药组正常肿瘤组织减少,有出血和坏死,脂肪组织增多。结果表明,PEA和PED可抑制H22实体瘤小鼠的肿瘤生长,其机制与调节Th1/Th2细胞平衡和抑制COX-2与PGE2的表达有关。  相似文献   
17.
AIM: To investigate how human adipose-derived stem cells (hASCs) regulates the differentiation of Th17 cells in multiple sclerosis. METHODS: hASCs were isolated from the adipose tissues. Magnetic-activated cell sorting (MACS) kit was used to isolate CD4+ T cells from peripheral blood mononuclear cells (PBMCs) which were isolated by density gradient centrifugation. The percentage of CD4+ T cells was detected by flow cytometry. The activated CD4+ T cells were co-cultured with hASCs for about 4 d at different ratios of hASCs to CD4+ T cells (1:4 and 1:10) in a Th17 polarised condition. Another group adding anti-leukemia inhibitory factor (LIF) antibody was set up. Th17 cell proportion of the CD4+ T cells was determined by flow cytometry. The level of LIF in the supernatant of co-cultured system was measured by ELISA. The mRNA expression of retinoid-related orphan receptor γt (RORγt), interleukin-6 receptor (IL-6R), interleukin-23 receptor (IL-23R), LIF and leukemia inhibitory factor receptor (LIFR) was detected by real-time PCR. RESULTS: The result of flow cytometry suggested there were mainly hASCs, and the percentage of CD4+ T cells in the PBMCs were above 90% after MACS. The Th17 cell proportion decreased in 1:4 and 1:10 co-cultured groups in a dose-dependent manner. The mRNA expression of IL-6R, IL-23R and RORγt was downregulated and the expression of LIFR and LIF was up-regulated. When the anti-LIF was added into the co-cultured system, the ratio of Th17 cells increased and reached to the control level. The protein level of LIF obviously increased after co-cultured. After anti-LIF added, the mRNA expression of RORγt and IL-6R was up-regulated. CONCLUSION: hASCs inhibits the differentiation of Th17 cells from multiple sclerosis patients through the competitive inhibition of LIF/IL-6 by secreting LIF.  相似文献   
18.
J. Luo  F.R. Huang  C.L. Xiao  W. Chen  S.W. Jiang  J. Peng   《Livestock Science》2009,126(1-3):286-291
The present study was designed to investigate the effect of dietary fish oil supplementation on piglet T helper cells (Th) polarization in relation to its impact on piglet serum interferon γ (IFN-γ) and interleukin 10 (IL-10) concentrations and splenic expression of Th1/Th2 characteristic genes. The diets of 18 gestating sows were supplemented with 7% lard (C) (n = 10) or 7% fish oil (T) (n = 8) from 10 d before parturition to weaning. At weaning, a split plot experiment was designed, 56 piglets, 28 each from sows fed with fish oil diet or lard diet, were divided into four groups of 7 replicates (one female and one castrated male per replicate) based on both sow diet during lactation and post-weaning piglet diet (C had 7% lard and T had 7% fish oil): CC, CT, TC, TT, and were fed the 7% fish oil or lard diet from day 35 to day 70. Serum concentrations of IFN-γ and IL-10, and Th1/Th2 related genes expression levels in spleen were measured and analyzed. The results showed that piglets fed with fish oil diet during post-weaning tended to have higher serum IFN-γ/IL-10 ratio (P = 0.09) than lard diet fed piglets. Lactation fish oil feeding increased splenic IL-12b, IL-12 receptor β2 (IL-12Rβ2), IL-2 and IFN-γ genes expression (P < 0.05 or P < 0.01) and post-weaning fish oil feeding increased splenic IL-12b (P = 0.06), IL-2 (P < 0.01) and IFN-γ (P = 0.08) mRNA expression than that in lard diet fed piglets at the end of this experiment. On the other hand, IL-4 gene expression (P = 0.01) in spleen was lower in weaned piglet from fish oil diet fed sows than that from lard diet fed sows. However, post-weaning piglets fed fish oil diet had higher splenic IL-4 (P = 0.06), IL-6 (P < 0.01) and IL-10 (P = 0.05) mRNA abundances than that fed with lard diet. These results indicated that dietary fish oil during lactation could increase Th1 polarization and accelerate immune maturation; while 7% fish oil in weaned piglets' diet was likely to increase Th2 cytokines expression.  相似文献   
19.
辅助性T细胞17(T help cell 17,Th17)是2005年新发现的能够分泌白细胞介素17的CD4+ T细胞,其与Th1、Th2、Tregs细胞共同构成CD4+ T细胞的4个亚群,该细胞与炎症、各种感染性疾病、肿瘤和自身免疫性疾病的发生密切相关。作者对Th17细胞及其在某些疾病或病理过程中作用的研究进展进行了简要综述。  相似文献   
20.
【目的】偃麦草(Thinopyrum)是小麦(Triticum aestivum L.)的多年生野生近缘植物,具有许多可用于小麦品种改良的优异基因。利用基因组特异重复序列可以研究物种的进化关系、绘制染色体指纹图谱及检测外源染色质。克隆十倍体长穗偃麦草(Th.ponticum(Host)Liu and Wang)基因组特异重复序列,可用于鉴定和追踪导入到小麦背景中的偃麦草遗传物质。【方法】通过构建十倍体长穗偃麦草小片段质粒文库,并对文库进行高密度点杂交(Dot-blot hybridization)筛选,结合荧光原位杂交(fluorescence in situ hybridization,FISH)技术,获得偃麦草基因组特异的重复序列,分析其在不同基因组及染色体上的分布特点。利用Repeat Masker在小麦族重复序列数据库(Triticeae repeat sequence database,TREP)及NCBI Gen Bank对特异重复序列进行比对分析,并设计偃麦草基因组特异重复序列的PCR引物。通过FISH分析和特异PCR引物扩增,对小麦-偃麦草衍生后代进行鉴定和选择。【结果】获得7条偃麦草基因组特异的重复序列。FISH分析表明,其在十倍体长穗偃麦草和六倍体中间偃麦草所有染色体两臂上均呈弥散型分布,且在不加小麦封阻DNA的情况下,能明确区分八倍体小偃麦中的偃麦草和小麦染色体。将其应用到小麦-偃麦草代换系和易位系的分子细胞学检测中,特异重复序列同样可以在不加封阻的情况下分辨出偃麦草染色体及染色体片段,而且信号相比基因组原位杂交(genomic in situ hybridization,GISH)更加特异和清晰。基于偃麦草基因组特异重复序列开发了90对引物,通过在中国春、十倍体长穗偃麦草和八倍体小偃麦中的扩增产物比较分析,筛选出36对(40%)偃麦草基因组特异PCR标记;利用这些特异引物对109份小麦-偃麦草衍生材料进行扫描,发现10对扩增效果较好的特异引物,其检测效率为73.3%—95%。【结论】获得偃麦草基因组特异的重复序列,开发了特异PCR扩增引物,可应用于小麦背景下偃麦草遗传物质的高效检测和跟踪。  相似文献   
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