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The detection of brucellosis and tularaemia infection agents is of particular interest for medical practice. The possibility of using enhanced chemiluminescence reactions for the determination of these agents is studied in this work. Light intensity depends on both the conjugate concentration used and the conditions at which the adsorption was performed. Optimal conditions for these test-systems were: ~ 20 μg/mL of Ig and 200 μg/mL (titre 1:20) of conjugate. As is seen from the chemiluminescent and spectrophotometric results the lowest determined concentrations are 10 and 30 ng/mL (for brucellosis) and 1 and 5 ng/mL (for tularaemia), respectively. Calibration curves in the antigen concentrations ranging from 10 to 2500 ng/mL (for brucellosis) and from 1 to 500 ng/mL (for tularaemia) are observed. Optical density depends linearly on the logarithm of the antigen concentration from 30 to 5000 ng/mL (for brucellosis) and from 5 to 250 ng/mL (for tularaemia). The results obtained permit the conclusion that the chemiluminescence method can be used in enzyme immunoanalysis for brucellosis and tularaemia antigens. 相似文献
23.
Jonathan W. Yewdell 《Molecular & cellular proteomics : MCP》2022,21(7):100230
In the 35 years since the revelation that short peptides bound to major histocompatibility complex class I and II molecules are the secret of the major histocompatibility complex–restricted nature of T-cell recognition, there has been enormous progress in characterizing the immunopeptidome, the repertoire of peptide presented for immunosurveillance. Here, the major milestones in the journey are marked, the contribution of proteasome-mediated splicing to the immunopeptidome is discussed, and exciting recent findings relating the immunopeptidome to the translatome revealed by ribosome profiling (RiboSeq) is detailed. Finally, what is needed for continued progress is opined about, which includes the infusion of talented young scientists into the antigen-processing field, currently undergoing a renaissance; thanks in part to the astounding success of T-cell–based cancer immunotherapy. 相似文献
24.
Yuka Kitamura Miho Tanaka Chiho Muramatsu Yasushi Akahori Hiroyuki Tsuda Yoshinobu Hattori 《Biochemical and biophysical research communications》2009,383(4):480-484
We reported comprehensive screening for antigens (Ags) overexpressed on various carcinomas via isolation of human monoclonal antibodies (mAbs) that may be therapeutic in a previous paper (Proc. Natl. Acad. Sci. USA 105, 7287-7292, 2008). Twenty-one distinct Ags highly expressed on several carcinomas were identified and 356 mAbs with unique sequences turned out to bind to one of the 21 Ags. Among them CADM1/IGSF4 which had been originally referred to as tumor suppressor lung cancer 1 (TSLC1) was included. Therefore we examined the expression of CADM1 in lung cancers in this study. Eight different anti CADM1 mAbs were used for immunohistochemical analysis of 29 fresh lung cancer specimens. Staining patterns were categorized to six groups based on the extent of positive staining and the localization of stained portions. While overexpression of CADM1 was observed on the cell surface of adenocarcinomas at a high frequency, around 60%, positive stainings were rarely observed on that of other lung carcinomas including squamous cell carcinomas. Moreover, some clones among the eight mAbs gave different staining patterns from those by the other clones against the same fresh specimen, suggesting presence of variant forms of CADM1 differentiated by mAbs. 相似文献
25.
摘要 目的:分析血管生成素样蛋白4(ANGPTL4)和Ⅱ型肺泡细胞表面抗原-6(KL-6)与急性呼吸窘迫综合征严重程度的关系及对预后的评估效能。方法:选择我院自2020年1月至2022年12月收治的120例急性呼吸窘迫综合征患者作为研究对象(观察组),根据氧合指数(PaO2/FiO2)分为轻度组、中度组和重度组;另选120例非急性呼吸窘迫综合征患者作为对照组。检测所有患者血清ANGPTL4和KL-6的表达水平,分析血清ANGPTL4和KL-6与APACHE Ⅱ评分、PaO2/FiO2的关系,使用受试者工作特征曲线(ROC)下面积(AUC)评价血清ANGPTL4联合KL-6对急性呼吸窘迫综合征预后的评估效能。结果:对比对照组,观察组血清ANGPTL4、KL-6的表达水平均明显升高(P<0.05);血清ANGPTL4、KL-6的表达水平在轻度组、中度组和重度组中差异有统计学意义,且急性呼吸窘迫综合征越严重,升高越明显(P<0.05);经Pearson相关性分析,急性呼吸窘迫综合征患者血清ANGPTL4、KL-6的表达水平与PaO2/FiO2呈负相关,与APACHE Ⅱ评分呈正相关(P<0.05);经ROC曲线分析,血清ANGPTL4联合KL-6预测急性呼吸窘迫综合征患者入院28d内死亡的敏感度为90.14%、特异度为65.74%,AUC为0.900。结论:血清ANGPTL4、KL-6表达水平升高与急性呼吸窘迫综合征严重程度增大密切相关,两者联合在患者预后评估中具有一定价值,可作为判断病情及预后的辅助指标。 相似文献
26.
摘要 目的:探讨细胞角蛋白19片段(CYFRA21-1)、基质金属蛋白酶-3(MMP-3)及癌胚抗原(CEA) 和细胞学联合检查对恶性胸腔积液的诊断价值。方法:选择2020年1月至2023年1月我院接诊的100例胸腔积液患者进行研究,并根据病理结果分为实验组47例(病理检查结果恶性),对照组53例(病理检查结果良性),分析血清CYFRA21-1、MMP-3及CEA 和细胞学水平变化情况及其的诊断价值。结果:实验组患者血清血清CYFRA21-1、MMP-3及CEA水平显著高于对照组,差异显著(P<0.05);实验组患者CYFRA21-1、MMP-3及CEA 和细胞学阳性率均显著高于对照组,差异显著(P<0.05);CYFRA21-1诊断恶性胸腔积液的AUC为0.989,95%CI为0.977~1.000;MMP-3诊断恶性胸腔积液的AUC为0.979,95%CI为0.964~0.994;CEA 诊断恶性胸腔积液的AUC为0.982,95%CI为0.967~0.997;细胞学诊断恶性胸腔积液的AUC为0.823,95%CI为0.766~0.879,联合检测时AUC为0.995,95%CI为0.990~1.000,较单独检测曲线下面积比较显著差异;且特异度、准确度均较单独检测更高。结论:CYFRA21-1、MMP-3及CEA 和细胞学联合检查可有效提高诊断恶性胸腔积液的准确性,临床应用价值高。 相似文献
27.
The T-cell deficiency of nude mice is due to an abnormal differentiation of the thymus epithelium; it can be persistently corrected by grafting a neonatal thymus. However, grafted adult thymuses or epithelial thymuses are not repopulated by large numbers of host-derived lymphocytes, as is the case when a whole neonatal thymus is grafted. Furthermore, the repopulation of the spleen and lymph nodes by T cells is less pronounced than after whole neonatal thymus transplantation, and the restoration of the reactivity to T-cell mitogens is irregular. Therefore, the integrity and the age of the thymus graft are important for a good restoration of the T-lymphoid system of congenitally athymic animals. 相似文献
28.
Lin Xiao Can Chen Zhendong Li Sumin Zhu Johan Ck Tay Xi Zhang Shijun Zha Jieming Zeng Wee Kiat Tan Xin Liu Wee Joo Chng Shu Wang 《Cytotherapy》2018,20(3):420-435
Vγ9Vδ2 T cells are a minor subset of lymphocytes in the peripheral blood that has been extensively investigated for their tolerability, safety and anticancer efficacy. A hindrance to the broad application of these cells for adoptive cellular immunotherapy has been attaining clinically appropriate numbers of Vγ9Vδ2 T cells. Furthermore, Vγ9Vδ2 T cells exist at low frequencies among cancer patients. We, therefore, sought to conceive an economical method that allows for a quick and robust large-scale expansion of Vγ9Vδ2 T cells. A two-step protocol was developed, in which peripheral blood mononuclear cells (PBMCs) from healthy donors or cancer patients were activated with Zometa and interleukin (IL)-2, followed by co-culturing with gamma-irradiated, CD64-, CD86- and CD137L-expressing K562 artificial antigen-presenting cells (aAPCs) in the presence of the anti-CD3 antibody OKT3. We optimized the co-culture ratio of K562 aAPCs to immune cells, and migrated this method to a G-Rex cell growth platform to derive clinically relevant cell numbers in a Good Manufacturing Practice (GMP)-compliant manner. We further include a depletion step to selectively remove αβ T lymphocytes. The method exhibited high expansion folds and a specific enrichment of Vγ9Vδ2 T cells. Expanded Vγ9Vδ2 T cells displayed an effector memory phenotype with a concomitant down-regulated expression of inhibitory immune checkpoint receptors. Finally, we ascertained the cytotoxic activity of these expanded cells by using nonmodified and chimeric antigen receptor (CAR)–engrafted Vγ9Vδ2 T cells against a panel of solid tumor cells. Overall, we report an efficient approach to generate highly functional Vγ9Vδ2 T cells in massive numbers suitable for clinical application in an allogeneic setting. 相似文献
29.
Expression of protective antigen in transgenic plants: a step towards edible vaccine against anthrax 总被引:5,自引:0,他引:5
Aziz MA Singh S Anand Kumar P Bhatnagar R 《Biochemical and biophysical research communications》2002,299(3):345-351
Protective antigen (PA) is the most potent molecule for vaccination against anthrax. In the present study, we have successfully integrated protective antigen gene in nuclear genome of tobacco plants by Agrobacterium mediated leaf-disc transformation method. Expression of protective antigen gene was detected by immunoblot analysis using antisera raised against purified PA. A distinct band of approximately 83kDa lighted up in the protein extracted from transformed plants while there was no such band in untransformed plants. The plant expressed PA showed biological activity just like native PA, which was demonstrated by cytolytic assay on macrophage like cell lines with lethal factor. This study establishes for the first time expression of PA gene in a plant system and thus marks the first milestone towards developing edible vaccine against anthrax. 相似文献
30.