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61.
Natural polyreactive secretory immunoglobulin A autoantibodies as a possible barrier to infection in humans. 总被引:9,自引:1,他引:9 下载免费PDF全文
Secretory immunoglobulin A (S-IgA) was investigated in human secretions for the presence of natural antibodies (Abs) acting as the first "immune barrier" to infection before induction or boosting of specific responses. These molecules could be the secretory counterpart of the natural Abs in serum that were previously shown by our laboratory to be polyreactive to autoantigens. Significant levels of S-IgA Abs to human actin, myosin, tubulin, and spectrin were detected in 10 saliva and 8 colostrum samples from normal subjects. Computer-assisted analysis of immunoblots of extracts from human muscles showed these Abs to react with a large number of autoantigens. Their polyreactivity was confirmed by cross-inhibition and by immunoblotting studies of affinity-purified natural Abs, assayed against a large variety of surface or secreted antigens from Streptococcus pyogenes. The thiocyanate elution method showed that functional affinities of some natural Abs can be of the same order of magnitude as those of tetanus vaccine antitoxins. Moreover, nonimmune binding of these natural Abs to the gut protein Fv (Fv-fragment binding protein) can enhance their effector functions. This demonstrates that human secretions contain polyreactive auto-Abs which can also react with pathogens. These secretory Abs of "skeleton key" specificities are possibly produced by a primordial B-1-cell-associated immune system and can be involved in a plurispecific mucosal protection against pathogens, irrespective of the conventional immune response. 相似文献
62.
Li N Fan XG Chen ZH Huang Y Quan J Liu ZB 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2005,113(10):647-654
Unmethylated CpG dinucleotides in bacterial DNA or synthetic oligodeoxynucleotides containing immunostimulatory CpG motifs (CpG ODN) are known as a potent Th1-like immune enhancer in vertebrates. Chronic hepatitis B is the immunocompromising condition. We therefore investigated the effects of CpG ODN on cultured cells from chronic hepatitis B patients and healthy controls. The inhibitory effects of CpG ODN on hepatitis B virus (HBV) were also studied. The secretion of IFN-alpha by CpG ODN-activated peripheral blood mononuclear cells (PBMCs) from chronic hepatitis B patients and healthy controls was significantly increased when compared with PBMCs alone or GpC ODN-stimulated PBMCs. After activation with CpG ODN, the IFN-alpha secretion by chronically HBV-infected patient PBMCs is less than that by healthy control PBMCs. Treatment of HepG2 2.2.15 cells with culture supernatants of PBMCs activated by CpG ODN can significantly suppress the secretion of HBsAg, HBeAg and HBV DNA as compared with that of PBMCs without CpG ODN activation under the same conditions. No inhibitory effect on the replication of HBV was found for CpG ODN treatment alone. Our results indicated that CpG ODN could efficiently enhance the immune response of chronic hepatitis B patients. Moreover, the CpG ODN-activated PBMCs from chronic hepatitis B patients were able to significantly inhibit HBV replication in vitro, suggesting that CpG ODN may be a potential immunoregulator against HBV infection in the future. 相似文献
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64.
Methods for obtaining and analyzing unattended polysomnography data for a multicenter study. Sleep Heart Health Research Group 总被引:4,自引:0,他引:4
Redline S Sanders MH Lind BK Quan SF Iber C Gottlieb DJ Bonekat WH Rapoport DM Smith PL Kiley JP 《Sleep》1998,21(7):759-767
This paper reviews the data collection, processing, and analysis approaches developed to obtain comprehensive unattended polysomnographic data for the Sleep Heart Health Study, a multicenter study of the cardiovascular consequences of sleep-disordered breathing. Protocols were developed and implemented to standardize in-home data collection procedures and to perform centralized sleep scoring. Of 7027 studies performed on 6697 participants, 5534 studies were determined to be technically acceptable (failure rate 5.3%). Quality grades varied over time, reflecting the influences of variable technician experience, and equipment aging and modifications. Eighty-seven percent of studies were judged to be of "good" quality or better, and 75% were judged to be of sufficient quality to provide reliable sleep staging and arousal data. Poor submental EMG (electromyogram) accounted for the largest proportion of poor signal grades (9% of studies had <2 hours artifact free EMG signal). These data suggest that with rigorous training and clear protocols for data collection and processing, good-quality multichannel polysomnography data can be obtained for a majority of unattended studies performed in a research setting. Data most susceptible to poor signal quality are sleep staging and arousal data that require clear EEG (electroencephalograph) and EMG signals. 相似文献
65.
本文报告了应用三种不同类型杀虫剂DDVP,残杀成和溴江菊酯点滴处理敏感株德国小蠊(Blattellagermanica)不同虫期后的药物敏感性以及带荚虫脱荚及其孵化情况。试验得出了不同虫期不同时间的LD50植和72h不同虫期对这3种药物敏感性的显著性测定(P值)的结果。发现不同虫期对这3种药物的敏感性之间关系的共同特点是:1.幼虫与雄虫敏感性差别显著(在DDVP和残杀威中)或者非常显著(在溴氰菊酯);2.雌虫与雄虫间差别在3种药物处理中均显著;3.雌虫与带荚虫在DDVP和溴氰菊酯处理中差别也非常显著。试验同时显示,3种药物不同浓度处理对德国小蠊脱荚及其孵化有十分显著的影响。其总的趋势是随着药物浓度的增高脱荚率明显地增加;相反,脱荚的孵化率则随着浓度的增加明显的下降。实验并得出脱荚的孵化与否和卵荚长度无明显关系。 相似文献
66.
IL-18基因修饰增强肿瘤抗原多肽致敏的树突状细胞体内诱导的抗肿瘤免疫反应 总被引:4,自引:0,他引:4
目的 :研究肿瘤抗原多肽致敏的白细胞介素 18(IL 18)基因修饰的树突状细胞体内诱导的抗肿瘤免疫反应。方法 :①以Lewis 3LL肺癌细胞特异性抗原肽mut1冲击致敏IL 18基因修饰的骨髓来源的树突状细胞 (DC IL 18 mut1) ,每次用其 1× 10 5 只皮下免疫小鼠 2次 ,然后测定脾细胞的NK活性及CTL杀伤活性 ;②以DC IL 18 mut1每次 2× 10 5 只皮下免疫 1次 ,然后再以 5× 10 53LL细胞攻击 ,在诱导及效应阶段分别以单抗阻断不同免疫成份 ,观察肿瘤的生长。结果 :以DC IL 18 mut1皮下免疫后可诱导出比DC mut1等免疫组更高水平的 3LL肺癌细胞特异性CTL ,并使NK活性明显增加 ;单抗体内阻断实验提示在DC IL 18 mut1免疫诱导阶段 ,CD4 + T细胞和抗原共刺激分子、IFN γ均起到重要作用 ,而效应阶段CD8+ T、IFN γ、NK起作用 ,而CD4 + T则是非必需的。结论 :DC IL 18 mut1皮下免疫后可诱导高水平的抗肿瘤免疫活性 ,其机理与抗原有效提呈、特异性CTL诱导、NK活性增加以及CD4 + 、CD8+ T、NK细胞、IFN γ参与密切相关。 相似文献
67.
Weimin Sun Ben Anderson Joy Redman Aubrey Milunsky Arlene Buller Matthew J McGinniss Franklin Quan Arturo Anguiano Stephen Huang Feras Hantash Charles Strom 《Genetics in medicine》2006,8(6):339-345
PURPOSE: The study's purpose was to understand the molecular basis for different clinical phenotypes of the 5T variant, a tract of 5 thymidines in intron 8 of the cystic fibrosis transmembrane conductance regulator (CFTR) gene, which disrupts processing of CFTR mRNA and reduces synthesis from the corresponding CFTR alleles. METHOD: We analyzed the polymorphic TG dinucleotide repeat adjacent to the 5T variant in intron 8 and the codon 470 in exon 10. Patients selected for this study were positive for both the 5T variant and the major cystic fibrosis mutation, Delta F508. Almost all Delta F508 mutation alleles occur in a 10TG-9T-470M haplotype. Therefore, it is possible to determine the haplotype of the 5T variant in trans. RESULTS: Of the 74 samples analyzed, 41 (55%) were 11TG-5T-470M, 31 (42%) were 12TG-5T-470V, and 2 (3%) were 13TG-5T-470M. Of the 49 cases for which we had clinical information, 17.6% of females (6/34) and 66.7% of males (10/15) showed symptoms resembling atypical cystic fibrosis. The haplotype with the highest penetrance in females (42% or 5/12) and more than 80% (5/6) in males is 12TG-5T-470V. We also evaluated 12 males affected with congenital bilateral absence of vas deferens and positive for the 5T variant; 10 of 12 had the 12TG-5T-470V haplotype. CONCLUSION: Overall, the 5T variant has a milder clinical consequence than previously estimated in females. The clinical presentations of the 5T variant are associated with the 5T-12TG-470M haplotype. 相似文献
68.
69.
70.
目的;评价男性抗精子抗体对体外受精-胚胎移植(IVF-ET)的影响。方法:以ELISA方法测定施行IVF-ET的150对不育夫妇中男方精浆抗精子抗体(AsAb)并分组:AsAb阳性组22例,AsAb阴性组128例。对比分析抗精子抗体及抗体类型对体外受精、卵裂和早期胚胎发育的影响,同时对移植后的妊娠率和流产率进行分析。结果:AsAb阳性组体外受精数明显低于AsAb阴性组(P<0.01),两组的卵裂数则无明显差异(P>0.05),而在阳性组中,不同抗体类型间体外受精、卵裂及胚胎质量无明显差异(P>0.05)。在移植日,AsAb阳性组的I级胚胎较阴性组低,而ⅢⅣ级胚胎和2原核受精细胞(2PN)明显增加(P<0.01)。两组移植后临床妊娠流产率无显著差异(P>0.05)。结论:AsAb能明显降低精子体外受精能力,对早期胚胎发育有损害。精子体处理不能完全清除AsAb对IVF影响。 相似文献