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31.
Previously, we reported that allogeneic skin grafts were rapidly rejected by CD28 and CD40 ligand double deficient mice mediated by CD8+ T cells. These results indicated that some elements in addition to CD28- and CD40-mediated costimulation provide stimulatory signals for the activation of donor-specific CD8+ T cells. In this report, we investigated the role of inflammation associated with transplantation on costimulation-independent priming of CD8+ T cell during graft rejection. B6 RAG1 KO mice were transplanted with BALB/c-skin and adoptively transferred with syngeneic CD8+ T cells the same day or 50 days after transplantation. When blockade of CD28- and CD40-mediated costimulation failed to prevent acute rejection of freshly transplanted skin grafts, it efficiently delayed rejection of well-healed skin grafts. These results showed that factors associated with transplantation have essential roles in inducing costimulation blockade-resistant allograft rejection. Costimulation blockade failed to prevent acute graft-infiltration of NK cells and increasing expression of intragraft IL-12 and IL-15. These factors may trigger the graft-infiltration and priming of CD8+ T cells to induce costimulation blockade-resistant allograft rejection.  相似文献   
32.
目的:探讨固本延衰方延缓亚急性衰老模型小鼠衰老的机制。方法:将60只小鼠随机分为4组,除正常对照组外均皮下注射D-半乳糖造成衰老模型,并给予不同剂量的固本延衰方治疗,分别用放免法及流式法测定脾淋巴细胞白细胞介素2及其受体水平。结果:衰老模型组IL-2及其受体水平明显低于正常对照组(P<0.05),固本延衰方各剂量组IL-2及其受体水平明显高于衰老模型组(P<0.05,P<0.01)。结论:提示固本延衰方通过提高衰老机体淋巴细胞IL-2及其受体表达水平,从而调节机体免疫功能延缓衰老。  相似文献   
33.
Abstract: We describe the use of restriction analysis on PCR-amplified DNA for detecting all B*27 subtypes except B*2710 and B*2711 (i.e. from B*2701 to B*2709). After detecting B*27 by Sty I, double digestions consisting of Sty I plus another informative enzyme led to subtype assignment. We used mismatched primers to create restriction sites when necessary. The method avoids group-specific amplifications and other laborious optimization procedures. It was successfully tested on a panel of well characterized cell lines covering different B*27 subtypes. Then, we studied a group of 57 ankylosing spondyiitis patients and 746 controls from the south of Spain. B*27 showed a very strong association with the disease (OR=211.27, P=\0˜7). B*2702 and B*2705 distribution in controls (20% and 77.1%, respectively) differed from previously reported data in the Spanish population. We unexpectedly found the B*2707 allele in our population (one control).  相似文献   
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35.
We report a patient with eosinophilia accompanied by Hodgkin's disease who showed remarkable increase in granulocyte-macrophage colony-stimulating factor (GM-CSF) in plasma but no increase in interleukin-5 (IL-5). The plasma GM-CSF level normalized as eosinophilia and lymphadenopathy disappeared after chemotherapy. Immunohistochemical study with immunoperoxidase staining technique showed a positive stain in lymph node cells by monoclonal anti-GM-CSF antibody. Eosinophilia is often accompanied by Hodgkin's disease, and several cases have been reported to show high levels of plasma IL-5. To our knowledge, this is the first report to show a high level of plasma GM-CSF in Hodgkin's disease with eosinophilia.  相似文献   
36.
大肠黏膜癌变过程中PTEN和p27的表达及相关性研究   总被引:3,自引:2,他引:1  
目的 :探讨PTEN及p2 7在大肠黏膜癌变过程中的表达及两者的相关性。方法 :采用免疫组织化学S -P法检测了 5 8例大肠癌 ,15例腺瘤性息肉及 11例配对的癌旁正常组织中抑癌基因PTEN和 p2 7的蛋白表达。分析PTEN和 p2 7的表达情况及与各种临床病理特征的关系及两者的相关性。结果 :在癌旁正常组织、大肠腺瘤性息肉、大肠癌组织中PTEN表达率分别为 (97.3± 4 .3) % ,(85 .2± 16 .8) % ,(13.8± 17.6 ) % ,呈递减趋势。大肠癌DukesA/B期组PTEN蛋白的高表达率为 88.9% ,明显高于DukesC/D期组中的 5 1.6 %。PTEN的高表达率与性别、年龄、肿瘤的大小、部位、分化程度、有无淋巴结转移无关。p2 7主要表达在细胞核 ,也有少量表达在细胞浆。在癌旁正常组织、大肠腺瘤性息肉、大肠癌组织中p2 7高表达率分别为 (98.8± 1.0 8) % ,(86 .0± 13.6 ) % ,(5 6 .8± 2 6 .0 ) % ,呈递减趋势。在大肠癌高、中分化组中 p2 7蛋白的表达率为 71.4 % ,明显高于低分化组中的 2 3.1%。p2 7的高表达率与患者的Dukes分期、性别、年龄、肿瘤的大小、部位及有无淋巴结转移无关。在大肠癌组织中 ,PTEN与 p2 7蛋白的表达呈正相关 (r =0 .6 4 2 )。结论 :PTEN及p2 7表达在癌旁正常组织、大肠腺瘤性息肉、大肠癌组织中均呈递减趋势 ,提示P  相似文献   
37.
应用APAAP法对15例肺癌TIL部分膜抗原的表达动态进行了免疫组化分析。结果显示:未经激活的TIL细胞,其膜抗原(CD~+3,CD~+4,CD~+8)的表达动态基本恒定,经IL-2激活的TIL细胞体外培养一段时期后,其CD~+3细胞数明显上升,同时CD~+8的表达逐渐减少,而CD~+4的表达在培养后期明显增多。  相似文献   
38.
Cytokines including IL-1 beta have been implicated in the pathophysiology of sepsis and the systemic inflammatory response. It is believed that certain critically ill patients may be 'primed' with respect to cytokine production, and that subsequent 'triggers' may cause exaggerated cytokine production in these patients with exacerbation of their clinical condition; however, no means of identifying 'primed' patients has been described. The presence of cytoplasmic IL-1 beta within peripheral blood mononuclear cells (PBMC) from patients in the ICU was investigated as a means of identifying 'primed' patients, using fluorescent antibody labelling and flow cytometry. The study revealed that PBMC from ICU patients had a different staining pattern for IL-1 beta than those from healthy subjects, and that PBMC from certain ICU patients did indeed stain strongly for IL-1 beta; however, the presence of these strongly staining cells was not associated with clinical condition or outcome. It is concluded that whilst it might be possible to identify 'primed' patients in the ICU using this technique, this is of no clinical value as a predictor of clinical course.  相似文献   
39.
40.
Gingival crevicular fluid (GCF) IL-8 and IL-1,1β levels were determined by sandwich enzyme-linked immunosorbent assays. Associations between IL-8 and IL-1β GCF levels, and between these cytokines and patient estrogen status were evaluated. IL-8 and IL-1β were detected more frequently and in higher amounts/30 s GCF sample in estrogen-deficient patients than in estrogensufficient patients. IL-8 and IL-1β GCF levels were significantly correlated. These lindings suggest that GCF IL-8 levels are associated with patient estrogen status and local IL-1β concentrations.  相似文献   
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