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1.
《Enfermedades infecciosas y microbiología clínica》2022,40(9):489-494
IntroductionIn order to deal with the current pandemic caused by the novel SARS-CoV-2 coronavirus several serological immunoassays have been recently developed with the objective of being used as a complementary diagnostic tool and to support the RT-PCR technique currently considered the “gold-standard” method. However, these new assays need to be evaluated and validated. The purpose of this study was to assess the performance of five immunoassays (two ELISA and three CLIA assays) and one rapid immunochromatographic test for the detection of anti-SARS-CoV-2 antibodies.MethodsFive semiquantitative immunoassays (MENARINI®, PALEX®, VIRCLIA®, ROCHE® and SIEMENS®) and one lateral flow rapid test (WONDFO®) were performed. A total of 124 samples were studied. Case serum samples (n = 78) were obtained from COVID-19 patients confirmed by real-time RT-PCR/epidemiological-clinical-radiological criteria, and control non-SARS-CoV-2 samples (n = 46) belonged to healthy healthcare workers involved in a seroprevalence study.ResultsOverall, the tests showed sensitivities around 70–90% and specificities greater than 95%, including the immunochromatographic test. In addition, we observed very good agreements among them, being better for the detection of IgG than for IgM antibodies (Cohen's kappa index of 0.95 for VIRCLIA® IgG with ROCHE®), as well as good diagnostic power of the tests as determined by the ROC curves.ConclusionsThis study demonstrates the proper performance of the different immunoassays in order to be applied in the clinical practice as support in the diagnostic approach and in the development of vaccines and seroepidemiological studies of COVID-19. 相似文献
2.
《Saudi Dental Journal》2022,34(5):346-354
BackgroundLipopolysaccharides (LPS) stimulate production of inflammatory cytokines. Chrysin is flavonoid beneficial for treatment of inflammatory conditions. Bone marrow mesenchymal stem cell (BM-MSC) exosomes have regenerative ability in different tissues.ObjectiveTo assess potential role of chrysin and BM-MSC exosomes on ultra-structure, viability and function of human dermal fibroblasts-adult (HDFa) stimulated by LPS.MethodsHDFa cells were divided into: Group I: Cells received no treatment. Group II: Cells were stimulated with LPS. Group III: LPS stimulated cells were treated with chrysin. Group IV: LPS stimulated cells were treated with exosomes.ResultsAfter 48 h, ultrastructural examination of HDFa cells in Group I revealed intact plasma membrane and numerous cytoplasmic organelles. Group II displayed destructed plasma membrane and apoptotic bodies. Group III showed intact plasma membrane with loss of its integrity at some areas. Group IV demonstrated intact plasma membrane that showed fusion with exosomes at some areas. Statistical analysis of MTT represented highest mean value of cell viability% in Group IV followed by Groups III, I and II respectively. Statistical analysis of enzyme-linked immunosorbent assay (ELISA) showed the highest mean value of interleukin-1β (IL-1β) was in Group II followed by Groups III, IV and I, while highest mean values of interleukin-10 (IL-10), nuclear factor-erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1) proteins were in Group I, followed by Groups IV, III and II respectively.ConclusionsLPS have harmful consequences on ultra-structure, viability and function of HDFa cells. BM-MSC exosomes have better regenerative action on inflamed fibroblasts in comparison to chrysin. 相似文献
3.
目的:通过建立开放式三明治酶联免疫分析方法(OE-ELISA),对雌二醇进行检测。方法:通过基因拼接构建质粒后在原核表达系统中制备小分子泛素相关修饰物蛋白-大肠杆菌麦芽糖结合蛋白-抗体轻链可变区(sumo-MBP-VL)和碱性磷酸酶-抗体重链可变区(ALP-VH)融合蛋白,并从产量和可溶性角度对两种蛋白的表达条件进行优化。将得到的两种蛋白纯化后分别作为包被抗体和酶标抗体,建立检测雌二醇的OE-ELISA方法。应用竞争ELISA和OE-ELISA测定不同浓度的雌二醇标准品,绘制标准曲线并计算两种方法的敏感性。结果:在质粒中加入sumo标签后,实现了sumo-MBP-VL融合蛋白的可溶性表达。在Rosetta 宿主菌中37℃诱导后得到大量的ALP-VH和sumo-MBP-VL融合蛋白。OE-ELISA测定雌二醇标准品的标准曲线为y=0.029 6x+1.302 9,r2=0.9961,敏感性为532 pg/mL,优于竞争ELISA 803 pg/mL的敏感性。结论:成功建立了检测雌二醇的OE-ELISA方法。 相似文献
4.
目的:评价酶联免疫法和胶体金法用于肺炎衣原体IgM抗体(CP-IgM)检测抗干扰能力的差异。方法:检测方法的优劣一定程度上源于该方法抗干扰能力的强弱,体现在准确率、敏感性、特异性等相关指标上,选取219例临床疑为肺炎衣原体感染患者血清作为研究样本,分别采用酶联免疫法和胶体金法检测肺炎衣原体IgM抗体。比较两种方法检测结果的真阳性例数、真阴性例数、假阳性例数、假阴性例数,并计算两种方法相应的准确率、敏感性、特异性,进而评价两种检测方法的抗干扰能力。结果:酶联免疫法检测肺炎衣原体IgM抗体比胶体金法的真阳性例数与真阴性例数多;而假阳性例数和假阴性例数均少;酶联免疫法的准确率、敏感性、特异性均高于胶体金法(P<0.05)。结论:酶联免疫法检测肺炎衣原体IgM抗体的抗干扰能力比胶体金法更强,检测结果准确性更高。 相似文献
5.
Karoliina Paarnio Anne Tuomisto Sara A. Vyrynen Juha P. Vyrynen Kai Klintrup Pasi Ohtonen Markus J. Mkinen Jyrki Mkel Tuomo J. Karttunen 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2019,127(8):561-569
Toll‐like receptors (TLRs) are involved in colorectal cancer (CRC) pathogenesis. However, the significance of serum TLR concentrations in CRC is unknown. We analyzed serum TLR2 and TLR4 concentrations with ELISA in preoperative samples from 118 patients with CRC and 88 matched controls. We also assessed tissue TLR expression with immunohistochemistry and by detecting serum determinants of systemic inflammation. Most participants (>70%) had undetectable serum TLR2. The mean serum TLR4 levels were lower in patients than in controls (1.1 vs 1.8 ng/mL; p = 0.015). Undetectable TLR4 was more common in stage I (39%) than in stages II–IV (11%, p < 0.001). TLR2 or TLR4 expression in tumor cells did not correlate with serum levels, but abundant TLR2 expression in normal colon epithelium was associated with detectable serum TLR2 (p = 0.034). Undetectable serum TLR2 was linked to high modified Glasgow prognostic scores (p = 0.010), high CRP levels (p = 0.013), blood vessel invasion (p = 0.013), and tended to be associated with worse 5‐year survival (p = 0.052). In conclusion, serum TLR2 levels were inversely associated with systemic inflammation in patients with CRC. Moreover, serum TLR2 levels might depend more on normal colorectal mucosa contributions than on tumor tissue contributions. Further studies are required to assess the prognostic value of serum TLR2. 相似文献
6.
《Journal of infection and chemotherapy》2022,28(11):1582-1583
Antibody titers against the superantigen, Yersinia pseudotuberculosis-derived mitogen, suggestive of mediating Kawasaki disease-like manifestation in Y. pseudotuberculosis infections, in immunoglobulin products were evaluated. Trace, but detectable titer was demonstrated in the products. Thus, attention is required when evaluating anti-Y. pseudotuberculosis-derived mitogen IgG titers in patient sera post intravenous immunoglobulin therapy. 相似文献
7.
Saurabh Shukla Anil Kumar Tripathi Shailendra Prasad Verma Deependra Kumar Yadav R. K. Tripathi Shweta Maurya Nidhi Awasthi 《Indian journal of hematology & blood transfusion》2021,37(2):210
Aplastic anemia (AA) is an immune-mediated disorder in which hematopoietic stem and progenitor cells are targeted by a number of cellular and molecular pathways. This case control study aims to investigate the association of interleukin-1beta (IL-1β) gene polymorphisms, (IL-1β-31, IL-1β-511 and IL-1β-3954) and their plasma levels with acquired AA. Genotyping was done by Restricted Fragment Length Polymorphism (PCR–RFLP) method and IL-1β plasma levels were evaluated in peripheral blood using ELISA. Increased level of IL-1β was reported to be significant in cases as compared to controls. The susceptibility of developing AA was higher in the cases for IL-1β-3954 genotype. IL-1β-511 genotype showed significant association with the severity groups of AA. No significant association was noticed in responder versus non-responder group. Plasma level of IL-1β gene was found to be significantly higher in severe and very-severe group of AA versus control group. Our findings suggest that IL-1β gene and its genotypes might be involved in the pathophysiology of AA and play a central role in the etiopathogenesis of AA. 相似文献
8.
Wei-Ting Hsu Chia-Yu Chang Chih-Hsuan Tsai Sung-Chan Wei Huei-Ru Lo Robert John S. Lamis Hui-Wen Chang Yu-Chan Chao 《Viruses》2021,13(2)
Porcine epidemic diarrhea virus (PEDV) is a coronavirus that causes serious and highly contagious enteric disease in swine worldwide. In this study, we constructed a recombinant baculovirus (S-Bac) expressing full-length spike protein of the virulent epidemic genotype 2b (G2b) PEDV strain for serological studies of infected pigs. We found that most spike-specific antibodies produced upon PEDV infection in pigs are conformation-specific and they could be detected on S-Bac-infected insect cells by immunofluorescent assay, but they were insensitive to Western blot analysis, the typical method for antiserum analysis. These results indicated that spike conformation is crucial for serum recognition. Since it is difficult to purify trimeric spike membrane protein for conventional enzyme-linked immunosorbent assay (ELISA), we used S-Bac to generate a novel cell-based ELISA for convenient PEDV detection. We analyzed 100 pig serum samples, and our cell-based ELISA exhibited a sensitivity of 100%, a specificity of 97%, and almost perfect agreement [Cohen’s kappa coefficient value (κ) = 0.98] with immunocytochemical staining results. Our cell-based ELISA rapidly presented antigen for proper detection of conformation-specific antibodies, making PEDV detection more convenient, and it will be useful for detecting many viral diseases in the future. 相似文献
9.
Li Zhang Yuli Kang Shujun Chen Li Wang Min Jiang Leihong Xiang 《Journal of dermatological science》2019,93(2):92-100