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171.
Identification of mimotopes for the H4 minor histocompatibility antigen   总被引:2,自引:0,他引:2  
The H4 minor histocompatibility antigen (HA) of mice includes a single immunogenic peptide presented by H-2Kb molecules that stimulates skin allograft rejection and is immunodominant in the stimulation of cytolytic T lymphocytes (CTL) specific for multiple minor HA. We have identified H4 mimotopes that are recognized by the H4-specific M9 CTL clone through the use of a random peptide library comprised of bacterial clones expressing an inducible fusion protein tailed with the octamer sequence SXIXFXXL. Eight discrete mimotopes were identified that sensitized RMA-S cells for lysis by M9 CTL down to concentrations of 10(-11) M. Comparable reactivity was observed with a short-term, H4- specific CTL line indicating that the mimotopes were not solely specific for the selecting M9 clone. All mimotopes included Gly at p2 and either Val or Ile at p4, suggesting a requirement for a hydrophobic residue with specific conformation. All mimotopes included either Arg or His at p7, implicating a requirement for a specific positively charged amino acid at that position. The sixth position was more variable with four of eight mimotopes having a Val residue with single mimotopes including alternative amino acids, the majority of which were hydrophobic. Analysis of mimotopes for hydrophobicity and charge by reverse-phase HPLC and capillary electrophoresis respectively indicated that (i) mimotopes with Val at both p4 and p6 were hydrophobically similar (but not identical) to the natural H4 peptide, and (ii) a S --> E substitution at p1 resulted in a peptide (EGIVFVRL) with charge characteristics equivalent to those of the natural H4 peptide.   相似文献   
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Sixteen children with recurrent abdominal pain (or: "recurrent syndrome"), regarded as migraine equivalent in childhood, were submitted to the 51-Cr EDTA gut permeability test. The results were compared with those obtained in 10 healthy young adults and in 11 control children. The gut permeability in the recurrent syndrome was significantly higher than in healthy adults and control children (p less than 0.0006): The following results were obtained: 4.83 +/- 0.40 (mean +/- SEM) in the children with recurrent abdominal pain, and 2.35 +/- 0.24 2.51 +/- 0.21 in the healthy young adults and control children, respectively. The implications of these findings as far as migraine is concerned, are discussed.  相似文献   
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目的:建立一种高灵敏度、高特异性、精确、简便的微孔板酶联夹心杂交技术,定量检测人IL-18mRNN。方法:针对人IL-18mRNA RT-PCR产物—条链的不同区域序列设计—对特异探针,其中一条为捕获探针,5’端为氨基修饰,可以与微量DNA结合板表面的NOS基团共价结合,“竖直”地包被在微孔板内;另一条为检测探针,3’端标记生物素。提取人外周血单个核细胞中总RNA,进行RT-PCR扩增IL-18 mRNA,产物热变性后加入已包被捕获探针的微孔板内进行杂交,再加入检测探针与已杂交的产物结合,最后经亲和素-辣根过氧化物酶(SAV-HRP)系统检测杂交信号。结果:该法检测IL-18mRNA RT-PCR产物的灵敏度明显高于琼脂糖凝胶电泳,重复性良好,且结果数据化。结论:该方法具有操作简单、灵敏度高、特异性强等优点,适合于PCR扩增产物的定量检测。  相似文献   
178.
目的:探明son ic hedgehog信号通路中几个关键的效应蛋白son ic hedgehog(SHH)、Patched1(PTC1)、Smoothened(SMO)及GLI1在人胚胎前列腺组织中的定位表达及变化。方法:应用免疫组织化学方法研究SHH、PTC1、SMO及GLI1在不同胎龄(10~39周)人胚胎前列腺组织中的表达变化情况。结果:随胎龄增大,SHH、PTC1、SMO及GLI1在前列腺组织中的表达水平呈由弱变强,由强渐弱,又由弱转强的双峰变化趋势。SHH和SMO仅表达在胚胎前列腺上皮细胞中;而PTC1和GLI1主要表达在上皮细胞外,也可表达在腺体周围的间质中。结论:SHH信号通路参与了人胚胎前列腺发育的调控过程,可能对于腺体发育初期的诱导发生,以及后期的增殖、分化都具有重要的调控作用。  相似文献   
179.
Immunosuppression associated with ovarian cancer (OC) and resultant peritoneal carcinomatosis (PC) hampers the efficacy of many promising treatment options, including immunotherapies. It is hypothesized that oncolytic virus-based therapies can simultaneously kill OC and mitigate immunosuppression. Currently, reovirus-based anticancer therapy is undergoing phase I/II clinical trials for the treatment of OC. Hence, this study was focused on characterizing the effects of reovirus therapy on OC and associated immune microenvironment. Our data shows that reovirus efficiently killed OC cells and induced higher expression of the molecules involved in antigen presentation including major histocompatibility complex (MHC) class I, β2-microglobulin (β2M), TAP-1, and TAP-2. In addition, in the presence of reovirus, dendritic cells (DCs) overcame the OC-mediated phenotypic suppression and successfully stimulated tumor-specific CD8+ T cells. In animal studies, reovirus targeted local and distal OC, alleviated the severity of PC and significantly prolonged survival. These therapeutic effects were accompanied by decreased frequency of suppressive cells, e.g., Gr1.1+, CD11b+ myeloid derived suppressor cells (MDSCs), and CD4+, CD25+, FOXP3+ Tregs, tumor-infiltration of CD3+ cells and higher expression of Th1 cytokines. Finally, reovirus therapy during early stages of OC also resulted in the postponement of PC development. This report elucidates timely information on a therapeutic approach that can target OC through clinically desired multifaceted mechanisms to better the outcomes.  相似文献   
180.

Background  

Previous research has shown a loss of bone mineral density (BMD) during pregnancy. This loss has been correlated to the occurrence of back pain symptoms during pregnancy. The objective of this study was to evaluate whether persistence of back pain symptoms 2 years after pregnancy could be associated with BMD changes as measured by quantitative USG of the os calcis.  相似文献   
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