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Hui X, Zhang Q, Li J, Qin Y, Zhou X, Zhao X, Xu Y, Huang B. Establishment of 11-dehydro-thromboxane B2 time-resolved immunoassay and application in membranous nephropathy. Anal Biochem 2023; 677:115252. [PMID: 37488002 DOI: 10.1016/j.ab.2023.115252] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2023] [Revised: 07/13/2023] [Accepted: 07/17/2023] [Indexed: 07/26/2023]
Abstract
BACKGROUND 11-Dehydro-thromboxane B2 (11-dehydro-TXB2) is the final stable metabolite of thromboxane A2 (TXA2) and is involved in thrombus formation. Patients with membranous nephropathy (MN) are prone to thromboembolism events. METHODS Time-resolved fluorescence immunoassay (TRFIA) for 11-dehydro-TXB2 was established by indirect competitive method. The coated 11-dehydro-TXB2-BSA conjugate was used to bind the 11-dehydro-TXB2 antibody competitively to the 11-dehydro-TXB2 antigen in the samples, followed by Eu3+-labeled goat anti-mouse IgG antibody, to detect 11-dehydro-TXB2. This study measured 11-dehydro-TXB2 concentrations in serum samples from healthy individuals and patients with MN. RESULTS The linear range of TRFIA was 16.38-2000 pg/mL, the sensitivity was 4.70 pg/mL, the average coefficients of variation from intra-assay and inter-assay were 3.50% and 4.95%, respectively, and the recovery was 99.38%. The serum level of 11-dehydro-TXB2 in patients with MN was significantly higher than that in healthy subjects (P < 0.05). The serum 11-dehydro-TXB2 concentration detected by TRFIA was highly consistent with that by ELISA (ρ = 0.900). DISCUSSION This study successfully established a new highly sensitive method for the detection of 11-dehydro-TXB2 in serum. 11-Dehydro-TXB2 has great potential in evaluating the risk of thromboembolic events in patients with MN and is expected to be applied to other thromboembolic-related diseases.
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Affiliation(s)
- Xuxiang Hui
- College of Life Sciences and Medicine, Zhejiang Sci-Tech University, Hangzhou, China
| | - Qiuhua Zhang
- Jiangnan University Medicine Center, Wuxi, China
| | - Jiayu Li
- College of Life Sciences and Medicine, Zhejiang Sci-Tech University, Hangzhou, China
| | - Yuan Qin
- College of Life Sciences and Medicine, Zhejiang Sci-Tech University, Hangzhou, China
| | - Xiumei Zhou
- College of Life Sciences and Medicine, Zhejiang Sci-Tech University, Hangzhou, China
| | - Xueqin Zhao
- College of Life Sciences and Medicine, Zhejiang Sci-Tech University, Hangzhou, China
| | - Yan Xu
- Department of Nephrology Suzhou Ninth People's Hospital, Suzhou Ninth Hospital Affiliated to Soochow University, Suzhou, China
| | - Biao Huang
- College of Life Sciences and Medicine, Zhejiang Sci-Tech University, Hangzhou, China.
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McLean GR, Zhang Y, Ndoyi R, Martin A, Winer J. Rapid Quantification of SARS-CoV-2 Neutralising Antibodies Using Time-Resolved Fluorescence Immunoassay. Vaccines (Basel) 2022; 10:vaccines10122149. [PMID: 36560559 PMCID: PMC9785461 DOI: 10.3390/vaccines10122149] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Revised: 12/07/2022] [Accepted: 12/12/2022] [Indexed: 12/23/2022] Open
Abstract
The quantification of neutralising antibodies (NAb) for SARS-CoV-2 has become an important tool for monitoring protective immunity following infection or immunisation. In this study, we evaluated using World-Health-Organisation-standard immunoglobulin preparations, a novel point-of-care test that quantitates NAb by time-resolved fluorescent immunoassay. The assay provided robust data of binding antibody units (BAU) in 15 min that were well correlated with NAb values obtained by traditional in vitro neutralisation assay. The data also correlated well to spike-receptor-binding domain-binding antibodies over a broad range of plasma dilutions. The assay was extremely sensitive, able to detect positive samples after dilution 1:10,000 and over a wide range of BAU. Assay specificity was estimated at 96% using Pre-COVID-19 serum samples when applying a cut-off value of 47 BAU/mL, although readings of up to 100 BAU/mL could be considered borderline. This point-of-care diagnostic test is useful for rapid population screening and includes the use of capillary blood samples. Furthermore, it provides results for SARS-CoV-2 NAb in 15 min, which can inform immediate decisions regarding protective immunity levels and the need for continued COVID immunisations.
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Affiliation(s)
- Gary R. McLean
- School of Human Sciences, London Metropolitan University, London N7 8DB, UK
- National Heart and Lung Institute, Imperial College London, London W2 1PG, UK
- Correspondence:
| | - Yueke Zhang
- PremaLabs Diagnostics UK Ltd., London W1J 6ER, UK
| | - Rene Ndoyi
- PremaLabs Diagnostics UK Ltd., London W1J 6ER, UK
| | - Adam Martin
- PremaLabs Diagnostics UK Ltd., London W1J 6ER, UK
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ŞEN YUVAYAPAN S, ÇOLAK AT, ŞAHİN O, CELIK C. Synthesis, Characterization, and Use of Lanthanide Chelate of β-Diketonate Based Ligand as a Luminescent Biolabel. JOURNAL OF THE TURKISH CHEMICAL SOCIETY, SECTION A: CHEMISTRY 2021. [DOI: 10.18596/jotcsa.949970] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
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Gallian B, Zaeimian MS, Hau D, AuCoin D, Zhu X. A Highly Sensitive Time-Gated Fluorescence Immunoassay Platform Using Mn-Doped AgZnInS/ZnS Nanocrystals as Signal Transducers. FRONTIERS IN PHYSICS 2021; 8:625424. [PMID: 33816457 PMCID: PMC8009851] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
In this work, a time-gated immunoassay platform using low-energy excitable and fluorescence long-lived Mn:AgZnInS/ZnS nanocrystals as signal transducers was developed and applied to the detection of the capsular polysaccharide (CPS) of Burkholderia pseudomallei, a Gram-negative bacterium that is the causative agent of melioidosis. CPS is a high molecular weight antigen displayed and is shed from the outer membrane of B. pseudomallei. The immunoassay using the time-gated platform presents a limit of detection at around 23 pg/ml when CPS is spiked in human serum.
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Affiliation(s)
- Brandon Gallian
- Department of Electrical and Biomedical Engineering, University of Nevada, Reno, NV, United States
- Biomedical Engineering Program, University of Nevada, Reno, NV, United States
| | - Masoumeh Saber Zaeimian
- Department of Electrical and Biomedical Engineering, University of Nevada, Reno, NV, United States
- Biomedical Engineering Program, University of Nevada, Reno, NV, United States
| | - Derrick Hau
- Department of Microbiology and Immunology, School of Medicine, University of Nevada, Reno, NV, United States
| | - David AuCoin
- Department of Microbiology and Immunology, School of Medicine, University of Nevada, Reno, NV, United States
| | - Xiaoshan Zhu
- Department of Electrical and Biomedical Engineering, University of Nevada, Reno, NV, United States
- Biomedical Engineering Program, University of Nevada, Reno, NV, United States
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Qin J, Yuan X, Liu C, Jia J, Zhang Y, Li W. Development of a time-resolved fluoroimmunoassay for measuring plasma growth hormone in Nile tilapia (Oreochromis niloticus). Gen Comp Endocrinol 2020; 287:113357. [PMID: 31821794 DOI: 10.1016/j.ygcen.2019.113357] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/16/2019] [Revised: 11/12/2019] [Accepted: 12/06/2019] [Indexed: 01/27/2023]
Abstract
Growth hormone is a hormone secreted from the pituitary and is involved in the regulation of most major physiological processes such as growth, development and metabolism. Therefore, an accurate and sensitive detection method is needed for the detection of tilapia serum Gh level. Phage display technology is widely used in the expression of antibody fragments, in which fragments of antibodies are expressed as a fusion with phage proteins and are displayed on the phage surface for easy screening. Time-resolved fluorescence immunoassay (TRFIA) is a microanalysis method developed nearly two decades ago and is one of the most sensitive analytical techniques. With the use of a special lanthanide, the detection background can be distinguished, which can greatly improve the sensitivity of detection. In this report, we cloned the VH and VL DNA fragments from the lymphocytes of rabbits immunized with recombinant Gh and assembled them with a linker to form a single-chain variable fragment (scFv) gene pool. Using phage display technology, we isolated scFv DNA fragments from the pool, which encode a protein that specifically binds to tilapia Gh. We then established Eu-DTTA-based TRFIA for measuring plasma Gh in tilapia. The sensitivity of double antibody sandwich Gh-TRFIA was 0.225 ng/ml, and the linear range of the standard curve was 0.225-250 ng/ml. The intra- and interassay coefficients of variation (CVs) were <9.1 and <4.5%, respectively. The cross-reactivities (CRs) of 1 μg/ml recombinant tilapia somatolactin (rtSl), prolactin (rtPrl) and thyroid-stimulating hormone beta subunit (rtTshb) were 0.042%, 0.472% and 0.036%, respectively. The sensitivity of direct competitive Gh-TRFIA was 0.208 ng/ml, and the linear range of the standard curve was 0.208-500 ng/ml. The intra- and interassay CVs were <4.8 and <7.1%, respectively. The CRs of 1 μg/ml rtSl, rtPrl and rtTshb were 0.041%, 0.079% and 0.073%, respectively. In conclusion, Gh-TRFIA is a safe (no concerns about radioactive isotopes), economical, and efficient detection method for the quantification of plasma Gh. Thus, the application of phage display technology for antibody screening and the use of TRFIA for tilapia Gh detection are conducive to research in the field of fish endocrinology.
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Affiliation(s)
- Jingkai Qin
- State Key Laboratory of Biocontrol, Institute of Aquatic Economic Animals and Guangdong Province Key Laboratory for Aquatic Economic Animals, Guangdong Provincial Engineering Technology Research Center of Healthy Breeding in Important Economic Fish, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, China
| | - Xi Yuan
- State Key Laboratory of Biocontrol, Institute of Aquatic Economic Animals and Guangdong Province Key Laboratory for Aquatic Economic Animals, Guangdong Provincial Engineering Technology Research Center of Healthy Breeding in Important Economic Fish, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, China
| | - Chenguang Liu
- State Key Laboratory of Biocontrol, Institute of Aquatic Economic Animals and Guangdong Province Key Laboratory for Aquatic Economic Animals, Guangdong Provincial Engineering Technology Research Center of Healthy Breeding in Important Economic Fish, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, China
| | - Jirong Jia
- State Key Laboratory of Biocontrol, Institute of Aquatic Economic Animals and Guangdong Province Key Laboratory for Aquatic Economic Animals, Guangdong Provincial Engineering Technology Research Center of Healthy Breeding in Important Economic Fish, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, China
| | - Yazhou Zhang
- State Key Laboratory of Biocontrol, Institute of Aquatic Economic Animals and Guangdong Province Key Laboratory for Aquatic Economic Animals, Guangdong Provincial Engineering Technology Research Center of Healthy Breeding in Important Economic Fish, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, China
| | - Wensheng Li
- State Key Laboratory of Biocontrol, Institute of Aquatic Economic Animals and Guangdong Province Key Laboratory for Aquatic Economic Animals, Guangdong Provincial Engineering Technology Research Center of Healthy Breeding in Important Economic Fish, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, China.
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Gallian B, Dong G, Zhu X. A compact time-gated instrument for QDs with low excitation energy and millisecond fluorescence lifetime as signal reporters, and its detection application. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2019; 90:104701. [PMCID: PMC6781484 DOI: 10.1063/1.5111147] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Accepted: 09/16/2019] [Indexed: 06/12/2023]
Abstract
Recently, bright quantum dots (QDs) possessing low energy for excitation and long fluorescence lifetime in milliseconds have been reported. These QDs such as Mn doped I(II)-III-VI nanocrystals are promising for highly sensitive time-gated sensing applications with a portable or small benchtop “personal” instrument because their unique optical properties not only ensure a high signal-to-background ratio in time-gated fluorescence-intensity (TGFI) measurement but also significantly simplify the TGFI measurement instrument design criteria. In this work, following up the research progress on these QDs, we developed a compact TGFI measurement instrument with high sensitivity and cost-effectiveness for these QDs (more specifically Mn:AZIS/ZnS QDs) as signal reporters. We applied the instrument for sensitive detection of copper(ii) ions in highly autofluorescent rum (alcoholic beverage) in a fluorescence quenching assay utilizing these QDs for signal transduction. The results from this work suggest that this instrument together with bright QDs with low-energy for excitation and long fluorescence lifetimes should have potential to not only convert many regular (non-time-gated) QD-based fluorescence assays to time-gated assays for higher sensitivities or lower LODs, but also facilitate the development of highly sensitive assays for in-field or point-of-care testing.
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Affiliation(s)
| | | | - Xiaoshan Zhu
- Author to whom correspondence should be addressed: . Fax: 1-775-784-6627
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Optimized dual assay for the transgenes selection and screening in CHO cell line development for recombinant protein production. Biotechnol Lett 2019; 41:929-939. [PMID: 31321593 DOI: 10.1007/s10529-019-02711-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2019] [Accepted: 07/11/2019] [Indexed: 10/26/2022]
Abstract
OBJECTIVE To develop a simple robust methodology of screening multiple CHO cell clones secreting recombinant proteins to assess their specific productivity. RESULTS We developed a dual assay based on immunoassay measurements of a recombinant protein expression combined with staining of viable cells with resazurin. Following this approach, colonies can be simultaneously assessed for cell growth rate and for production of a recombinant protein. Combination of these two assays enables to estimate productivity of a recombinant protein per cell from the very early stages of a cell line development process (CLD) and exclude poor producers from further steps. Comparison of the dual assay with a standard CLD protocol followed by only analysis of protein expression level showed at least 10-20% increase in the amount of clones that can be included into pool of high-producers at early stages. This shortens duration of a typical CLD scheme from 23 to 19 weeks. CONCLUSIONS Our method: (i) allows to include into workflow clones that demonstrate slow growth during single cell cloning but producing high amounts of a target protein, which otherwise would be lost in standard protocols of cells screening; (ii) can be applied for testing of DNA vectors for transfection and protein production; (iii) can be used for monitoring the heterogeneity of cell population and analysis of stable pools productivity.
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Simultaneous quantitation of carbohydrate antigen 125 and carcinoembryonic antigen in human serum via time-resolved fluoroimmunoassay. Clin Chim Acta 2018; 483:222-226. [DOI: 10.1016/j.cca.2018.05.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2017] [Revised: 03/16/2018] [Accepted: 05/01/2018] [Indexed: 12/15/2022]
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9
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Cho U, Riordan DP, Ciepla P, Kocherlakota KS, Chen JK, Harbury PB. Ultrasensitive optical imaging with lanthanide lumiphores. Nat Chem Biol 2018; 14:15-21. [PMID: 29106397 PMCID: PMC5726931 DOI: 10.1038/nchembio.2513] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Accepted: 10/02/2017] [Indexed: 11/12/2022]
Abstract
In principle, the millisecond emission lifetimes of lanthanide chelates should enable their ultrasensitive detection in biological systems by time-resolved optical microscopy. In practice, however, lanthanide imaging techniques have provided no better sensitivity than conventional fluorescence microscopy. Here, we identified three fundamental problems that have impeded lanthanide microscopy: low photon flux, inefficient excitation, and optics-derived background luminescence. We overcame these limitations with a new lanthanide imaging modality, transreflected illumination with luminescence resonance energy transfer (trLRET), which increases the time-integrated signal intensities of lanthanide lumiphores by 170-fold and the signal-to-background ratios by 75-fold. We demonstrate that trLRET provides at least an order-of-magnitude increase in detection sensitivity over that of conventional epifluorescence microscopy when used to visualize endogenous protein expression in zebrafish embryos. We also show that trLRET can be used to optically detect molecular interactions in vivo. trLRET promises to unlock the full potential of lanthanide lumiphores for ultrasensitive, autofluorescence-free biological imaging.
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Affiliation(s)
- Ukrae Cho
- Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, California 94305, USA
| | - Daniel P. Riordan
- Department of Biochemistry, Stanford University School of Medicine, Stanford, California 94305, USA
| | - Paulina Ciepla
- Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, California 94305, USA
| | - Kiranmai S. Kocherlakota
- Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, California 94305, USA
| | - James K. Chen
- Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, California 94305, USA
- Department of Developmental Biology, Stanford University School of Medicine, Stanford, California 94305, USA
| | - Pehr B. Harbury
- Department of Biochemistry, Stanford University School of Medicine, Stanford, California 94305, USA
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A time-resolved fluoroimmunoassay to assay the rabies virus glycoprotein: application for estimation of human rabies vaccine potency. Sci Rep 2017; 7:7288. [PMID: 28779162 PMCID: PMC5544697 DOI: 10.1038/s41598-017-07687-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2017] [Accepted: 06/29/2017] [Indexed: 02/06/2023] Open
Abstract
Replacement of the in vivo rabies vaccine potency test (NIH test) by in vitro methods had been discussed by several researcher including WHO expert working groups. In this paper, a time-resolved fluoroimmunoassay (TRFIA) for the assay of rabies virus glycoprotein in rabies vaccine was first established to estimate the rabies vaccine potency by using specific monoclonal antibody that only recognized the native, trimeric and immunogenic form of rabies virus glycoprotein. Potency of the rabies virus glycoprotein was assayed with satisfactory performance under optimal conditions, and the method demonstrated satisfactory results when applied in practical samples. The correlation coefficient of potency values obtained from the present TRFIA and ELISA was 0.912, and 0.903 for those from the present TRFIA and NIH test. These preliminary results confirmed that this TRFIA can replace ELISA with higher performance, and could be a promising replacement of the NIH test. Based upon these results, the present TRFIA seemed to be a convenient tool for evaluating rabies vaccine potency and its products at different stages accordingly.
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Fan J, Xiao H, Zhang J, Zhou B, Deng L, Zhang Y, Huang B. A magnetic nanoparticle-labeled immunoassay with europium and samarium for simultaneous quantification of serum pepsinogen I and II. Br J Biomed Sci 2017; 74:127-132. [PMID: 28521643 DOI: 10.1080/09674845.2017.1297216] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
OBJECTIVE To develop a novel immunoassay for the simultaneous determination of serum pepsinogen I (PG I) and pepsinogen II (PG II) by combining established methods of time-resolved fluoroimmunoassay (TRFIA) and magnetic nanoparticles separation. MATERIALS AND METHODS This new immunoassay method was characterised by immobilising primary antibodies on the surface of magnetic particles and labelled with stable fluorescent chelates of europium and samarium. RESULTS Using magnetic nanoparticles, the TRFIA immunoassay exhibited broad dynamic assay ranges for PG I with detection limit of 0.33 ng/mL, while for PG II with detection limit of 0.38 ng/mL. Cross-reactivity between PGs I and II were <15. The intra- and inter-assay coefficient variations of the method were <3%, and the recoveries were in the range of 97-103% for serum samples. Bland-Altman analysis of 124 serum samples showed good consistency with a commercial TRFIA kit. For PG I, the mean (95% confidence interval) difference was 0.97 (-14.3-12.3) ng/mL, whilst for PG II the difference was 0.6 (-4.4-3.2) ng/mL. CONCLUSIONS Our data suggest that the method is feasible and could be developed into a platform for the routine clinical determination of PG I and PG II levels in human serum.
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Affiliation(s)
- J Fan
- a Key Laboratory of Nuclear Medicine, Ministry of Health, Jiangsu Key Laboratory of Molecular Nuclear Medicine , Jiangsu Institute of Nuclear Medicine , Wuxi , China
| | - H Xiao
- b Department of Clinical Laboratory , Wuxi Public Hospital , Wuxi , China
| | - J Zhang
- a Key Laboratory of Nuclear Medicine, Ministry of Health, Jiangsu Key Laboratory of Molecular Nuclear Medicine , Jiangsu Institute of Nuclear Medicine , Wuxi , China
| | - B Zhou
- a Key Laboratory of Nuclear Medicine, Ministry of Health, Jiangsu Key Laboratory of Molecular Nuclear Medicine , Jiangsu Institute of Nuclear Medicine , Wuxi , China
| | - L Deng
- a Key Laboratory of Nuclear Medicine, Ministry of Health, Jiangsu Key Laboratory of Molecular Nuclear Medicine , Jiangsu Institute of Nuclear Medicine , Wuxi , China
| | - Y Zhang
- a Key Laboratory of Nuclear Medicine, Ministry of Health, Jiangsu Key Laboratory of Molecular Nuclear Medicine , Jiangsu Institute of Nuclear Medicine , Wuxi , China
| | - B Huang
- a Key Laboratory of Nuclear Medicine, Ministry of Health, Jiangsu Key Laboratory of Molecular Nuclear Medicine , Jiangsu Institute of Nuclear Medicine , Wuxi , China
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Schmued L, Raymick J. Introducing Euro-Glo, a rare earth metal chelate with numerous applications for the fluorescent localization of myelin and amyloid plaques in brain tissue sections. J Neurosci Methods 2017; 279:79-86. [PMID: 27939963 DOI: 10.1016/j.jneumeth.2016.12.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2016] [Revised: 12/01/2016] [Accepted: 12/03/2016] [Indexed: 11/19/2022]
Abstract
The vast majority of fluorochromes are organic in nature and none of the few existing chelates have been applied as histological tracers for localizing brain anatomy and pathology. NEW METHOD In this study we have developed and characterized a Europium chelate with the ability to fluorescently label normal and pathological myelin in control and toxicant-exposed rats, as well as the amyloid plaques in aged AD/Tg mice. RESULTS This study demonstrates how Euro-Glo can be used for the detailed labeling of both normal myelination in the control rat as well as myelin pathology in the kainic acid exposed rat. In addition, this study demonstrates how E-G will label the shell of amyloid plaques in an AD/Tg mouse model of Alzheimer's disease a red color, while the plaque core appears blue in color. The observed E-G staining pattern is compared with that of well characterized tracers specific for the localization of myelin (Black-Gold II), degenerating neurons (Fluoro-Jade C), A-beta aggregates (Amylo-Glo) and glycolipids (PAS). COMPARISONS WITH EXISTING METHODS This study represents the first time a rare earth metal (REM) chelate has been used as a histochemical tracer in the brain. This novel tracer, Euro-Glo (E-G), exhibits numerous advantages over conventional organic fluorophores including high intensity emission, high resistance to fading, compatibility with multiple labeling protocols, high Stoke's shift value and an absence of bleed-through of the signal through other filters. CONCLUSIONS Euro-Glo represents the first fluorescent metal chelate to be used as a histochemical tracer, specifically to localize normal and pathological myelin as well as amyloid plaques.
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Affiliation(s)
- Larry Schmued
- National Center for Toxicological Research, Food and Drug Administration, 3900 NCTR Rd Jefferson AR, 72079, United States.
| | - James Raymick
- National Center for Toxicological Research, Food and Drug Administration, 3900 NCTR Rd Jefferson AR, 72079, United States.
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A Magnetic Nanoparticle-Based Time-Resolved Fluoroimmunoassay for Determination of the Cytokeratin 19 Fragment in Human Serum. J Fluoresc 2015; 25:361-7. [DOI: 10.1007/s10895-015-1518-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2014] [Accepted: 01/20/2015] [Indexed: 12/15/2022]
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Rossant CJ, Matthews C, Neal F, Colley C, Gardener MJ, Vaughan T. Versatility of Homogeneous Time-Resolved Fluorescence Resonance Energy Transfer Assays for Biologics Drug Discovery. ACTA ACUST UNITED AC 2014; 20:508-18. [DOI: 10.1177/1087057114557464] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Identification of potential lead antibodies in the drug discovery process requires the use of assays that not only measure binding of the antibody to the target molecule but assess a wide range of other characteristics. These include affinity ranking, measurement of their ability to inhibit relevant protein-protein interactions, assessment of their selectivity for the target protein, and determination of their species cross-reactivity profiles to support in vivo studies. Time-resolved fluorescence resonance energy transfer is a technology that offers the flexibility for development of such assays, through the availability of donor and acceptor fluorophore-conjugated reagents for detection of multiple tags or fusion proteins. The time-resolved component of the technology reduces potential assay interference, allowing screening of a range of different crude sample types derived from the bacterial or mammalian cell expression systems often used for antibody discovery projects. Here we describe the successful application of this technology across multiple projects targeting soluble proteins and demonstrate how it has provided key information for the isolation of potential therapeutic antibodies with the desired activity profile.
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Affiliation(s)
- Christine J. Rossant
- Antibody Discovery and Protein Engineering, MedImmune, Cambridge, UK
- Crescendo Biologics, Cambridge, UK
| | - Carl Matthews
- Antibody Discovery and Protein Engineering, MedImmune, Cambridge, UK
| | - Frances Neal
- Antibody Discovery and Protein Engineering, MedImmune, Cambridge, UK
| | - Caroline Colley
- Antibody Discovery and Protein Engineering, MedImmune, Cambridge, UK
| | | | - Tristan Vaughan
- Antibody Discovery and Protein Engineering, MedImmune, Cambridge, UK
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Lin G, Huang H, Liu T, He C, Liu J, Chen S, Hou J, Ren Z, Dong W, Wu Y. A time-resolved fluoroimmunoassay for the quantitation of rabies virus nucleoprotein in the rabies vaccine. J Virol Methods 2014; 206:89-94. [DOI: 10.1016/j.jviromet.2014.06.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2014] [Revised: 05/30/2014] [Accepted: 06/03/2014] [Indexed: 11/28/2022]
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16
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Duan RR, Wang L, Huo WQ, Chen S, Zhou XH. Synthesis, characterization, and DNA binding of two copper(II) complexes as DNA fluorescent probes. J COORD CHEM 2014. [DOI: 10.1080/00958972.2014.946918] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Affiliation(s)
- Ran-Ran Duan
- College of Science, South China Agricultural University, Guangzhou, PR China
| | - Lu Wang
- College of Science, South China Agricultural University, Guangzhou, PR China
| | - Wei-Qiang Huo
- College of Science, South China Agricultural University, Guangzhou, PR China
| | - Shi Chen
- College of Science, South China Agricultural University, Guangzhou, PR China
- Institute of Biomaterial, South China Agricultural University, Guangzhou, PR China
| | - Xiao-Hua Zhou
- College of Science, South China Agricultural University, Guangzhou, PR China
- Institute of Biomaterial, South China Agricultural University, Guangzhou, PR China
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Novel and remarkable enhanced-fluorescence system based on gold nanoclusters for detection of tetracycline. Talanta 2014; 122:36-42. [DOI: 10.1016/j.talanta.2013.12.008] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2013] [Revised: 12/01/2013] [Accepted: 12/04/2013] [Indexed: 11/23/2022]
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18
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Ye Y, Hu Z, Liu J, Chen G, Zhou Y. A new Eu(3+)-labeled method for anticardiolipin antibody IgM. J Clin Lab Anal 2014; 28:335-40. [PMID: 24659029 DOI: 10.1002/jcla.21690] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2013] [Revised: 08/22/2013] [Accepted: 08/30/2013] [Indexed: 11/08/2022] Open
Abstract
BACKGROUND The anticardiolipin antibodies (aCL) test has become a laboratory standard for the clinical diagnosis of antiphospholipid syndrome (APS). To better the quantitative detection of aCL-IgM so as to classify patients correctly and timely as APS positive, we established herein a new immunoassay based on a time-resolved fluoroimmunoassay (TRFIA). METHODS The complex of cardiolipin plus bovine anti-β2 glycoprotein-I was used as antigen fixed on microtiter plates to detect serum aCL-IgM, and Eu(3+) -labeled rabbit antihuman IgM was used as conjugate. The precision, sensitivity, specificity, coefficient of recovery, and stability of the assay were evaluated, and comparison with the traditional, classical enzyme-linked immunosorbent assay (ELISA) was also made. RESULTS The detection limit of the aCL-IgM TRFIA kit we established was 0.1 MPL U/ml, with a wider detectable range than commercial ELISA ones when a strong-positive specimen was diluted from 2,630.9 to 0.08 MPL U/ml. There was a good liner range within 0.16 to 2,630.9 MPL U/ml, whereas it was within 5.14 to 328.86 MPL U/ml when using three commercial ELISA ones. The average intra- and interassay variability was 3.19 and 3.70%, respectively. The mean recovery rate was 101.95%. The clinical diagnostic specificity was 98%. Additionally, the established assay kit presented good characteristics of stability and correlated well with the ELISA, and the correlation coefficient was 0.955. CONCLUSION The aCL-IgM TRFIA provides an approach to a more sensitive and reliable diagnosis of APS. Further validation of its use is required.
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Affiliation(s)
- Yan Ye
- Department of Clinical Laboratory, Affiliated Wuxi People's Hospital of Nanjing Medical University, Wuxi, China
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Hu Z, Liu J, Ye Y, Zhou Y, Yu L. DETECTION OF ANTICARDIOLIPIN ANTIBODY IGM BY SM3+-LABELED TIME-RESOLVED FLUOROIMMUNOASSAY. J Immunoassay Immunochem 2013; 34:255-65. [DOI: 10.1080/15321819.2012.709212] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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20
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Chen ZH, Wu YS, Chen MJ, Hou JY, Ren ZQ, Sun D, Liu TC. A novel homogeneous time-resolved fluoroimmunoassay for carcinoembryonic antigen based on water-soluble quantum dots. J Fluoresc 2013; 23:649-57. [PMID: 23471623 DOI: 10.1007/s10895-013-1175-0] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2012] [Accepted: 02/24/2013] [Indexed: 10/27/2022]
Abstract
Quantum dots are not widely used in clinical diagnosis. However, the homogeneous time-resolved fluorescence assay possesses many advantages over current methods for the detection of carcinoembryonic antigen (CEA), a primary marker for many cancers and diseases. Therefore, a novel luminescent terbium chelates- (LTCs) and quantum dots-based homogeneous time-resolved fluorescence assay was developed to detect CEA. Glutathione-capped quantum dots (QDs) were prepared from oil-soluble QDs with a 565 nm emission peak. Conjugates (QDs-6 F11) were prepared with QDs and anti-CEA monoclonal antibody. LTCs were prepared and conjugates (LTCs-S001) were prepared with another anti-CEA monoclonal antibody. The fluorescence lifetime of QDs was optimized for sequential analysis. The Förster distance (R0) was calculated as 61.9 Å based on the overlap of the spectra of QDs-6 F11 and LTCs-S001. Using a double-antibody sandwich approach, the above antibody conjugates were used as energy acceptor and donor, respectively. The signals from QDs were collected in time-resolved mode and analyzed for the detection of CEA. The results show that the QDs were suitable for time-resolved fluoroassays. The spatial distance of the donor-acceptor pair was calculated to be 61.9 Å. The signals from QDs were proportional to CEA concentration. The standard curve was LogY = 2.75566 + 0.94457 LogX (R = 0.998) using the fluorescence counts (Y) of QDs and the concentrations of CEA (X). The calculated sensitivity was 0.4 ng/mL. The results indicate that water-soluble QDs are suitable for the homogenous immunoassay. This work has expanded future applications of QDs in homogeneous clinical bioassays. Furthermore, a QDs-based homogeneous multiplex immunoassay will be investigated as a biomarker for infectious diseases in future research.
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Affiliation(s)
- Zhen-Hua Chen
- School of Biotechnology, Southern Medical University, Guangzhou, 510515, Guangdong, People's Republic of China
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21
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Evolution of biologics screening technologies. Pharmaceuticals (Basel) 2013; 6:681-8. [PMID: 24276173 PMCID: PMC3817722 DOI: 10.3390/ph6050681] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2013] [Revised: 04/23/2013] [Accepted: 05/08/2013] [Indexed: 12/25/2022] Open
Abstract
Screening for biologics, in particular antibody drugs, has evolved significantly over the last 20 years. Initially, the screening processes and technologies from many years experience with small molecules were adopted and modified to suit the needs of biologics discovery. Since then, antibody drug discovery has matured significantly and is today investing earlier in new technologies that commercial suppliers are now developing specifically to meet the growing needs of large molecule screening. Here, we review the evolution of screening and automation technologies employed in antibody discovery and highlight the benefits that these changes have brought.
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22
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Pillai S, Krasnoperov L, Mustaev A. Simple no-chromatography procedure for amine-reactive Eu 3+ luminescent chelates optimal for bioconjugation. J Photochem Photobiol A Chem 2013; 255:16-23. [PMID: 23833546 DOI: 10.1016/j.jphotochem.2013.01.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Lanthanide ions luminescence has long life time enabling highly sensitive detection in time-gated mode. The synthesis of reactive lanthanide probes for covalent labeling of the objects of interest is cumbersome task due to the large size of the probes, complex multi-step procedures and the presence of sensitive groups, which often prevents introduction of reactive cross-linking functions optimal for conjugation. We suggest simple synthetic protocol for luminescent europium chelates based on serendipitous reaction yielding acylating compounds, whose reactivity is comparable to that of commonly used N-hydroxysuccinimide (NHS) esters. The probes react with proteins at pH 7.0 within several minutes at ambient temperature displaying high coupling efficiency. The resulting conjugates survive electrophoretic separation under denaturing conditions, which makes the labels useful in proteomic studies that rely on high detection sensitivity.
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Affiliation(s)
- Shyamala Pillai
- Department of Chemistry and Environmental Science, New Jersey Institute of Technology, University Heights, Newark, New Jersey 07102 ; PHRI Center, New Jersey Medical School, Department of Microbiology and Molecular Genetics, University of Medicine and Dentistry of New Jersey, 225 Warren Street, Newark, New Jersey 07103
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23
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Wirpsza L, Pillai S, Batish M, Marras S, Krasnoperov L, Mustaev A. Highly bright avidin-based affinity probes carrying multiple lanthanide chelates. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2012; 116:22-9. [PMID: 23018156 DOI: 10.1016/j.jphotobiol.2012.07.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2012] [Revised: 07/03/2012] [Accepted: 07/07/2012] [Indexed: 10/28/2022]
Abstract
Lanthanide ion luminescence has a long lifetime enabling highly sensitive detection in time-gated mode. The sensitivity can be further increased by using multiple luminescent labels attached to a carrier molecule, which can be conjugated to an object of interest. We found that up to 30 lanthanide chelates can be attached to avidin creating highly bright constructs. These constructs with Eu(3+) chelates display synergistic effect that enhance the brightness of heavily modified samples, while the opposite effect was observed for Tb(3+) chelates thereby significantly reducing their light emission. This undesirable quenching of Tb(3+) luminophores was completely suppressed by the introduction of an aromatic spacer between the chelate and the protein attachment site. The estimated detection limit for the conjugates is in the 10(-14)-10(-15) M range. We demonstrated a high sensitivity for the new probes by using them to label living cells of bacterial and mammalian origin.
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Affiliation(s)
- Laura Wirpsza
- Department of Chemistry and Environmental Sciences, New Jersey Institute of Technology, 151 Tiernan Hall, University Heights, Newark, NJ 07102, USA
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24
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Quantum-dot-based homogeneous time-resolved fluoroimmunoassay of alpha-fetoprotein. Anal Chim Acta 2012; 741:100-5. [DOI: 10.1016/j.aca.2012.06.042] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2012] [Revised: 06/18/2012] [Accepted: 06/20/2012] [Indexed: 11/24/2022]
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25
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Hötzer B, Medintz IL, Hildebrandt N. Fluorescence in nanobiotechnology: sophisticated fluorophores for novel applications. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2012; 8:2297-326. [PMID: 22678833 DOI: 10.1002/smll.201200109] [Citation(s) in RCA: 99] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2012] [Revised: 02/22/2012] [Indexed: 05/26/2023]
Abstract
Nanobiotechnology is one of the fastest growing and broadest-ranged interdisciplinary subfields of the nanosciences. Countless hybrid bio-inorganic composites are currently being pursued for various uses, including sensors for medical and diagnostic applications, light- and energy-harvesting devices, along with multifunctional architectures for electronics and advanced drug-delivery. Although many disparate biological and nanoscale materials will ultimately be utilized as the functional building blocks to create these devices, a common element found among a large proportion is that they exert or interact with light. Clearly continuing development will rely heavily on incorporating many different types of fluorophores into these composite materials. This review covers the growing utility of different classes of fluorophores in nanobiotechnology, from both a photophysical and a chemical perspective. For each major structural or functional class of fluorescent probe, several representative applications are provided, and the necessary technological background for acquiring the desired nano-bioanalytical information are presented.
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Affiliation(s)
- Benjamin Hötzer
- NanoBioPhotonics, Institut d'Electronique Fondamentale, Université Paris-Sud, 91405 Orsay Cedex, France
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26
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Lin GF, Liu TC, Zou LP, Hou JY, Wu YS. Development of a dual-label time-resolved fluoroimmunoassay for the detection of α-fetoprotein and hepatitis B virus surface antigen. LUMINESCENCE 2012; 28:401-6. [DOI: 10.1002/bio.2396] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2012] [Revised: 04/05/2012] [Accepted: 05/16/2012] [Indexed: 11/06/2022]
Affiliation(s)
- Guan-Feng Lin
- Institute of Antibody Engineering, School of Biotechnology; Southern Medical University; Guangzhou; 510515; Guangdong; P.R. China
| | - Tian-Cai Liu
- Institute of Antibody Engineering, School of Biotechnology; Southern Medical University; Guangzhou; 510515; Guangdong; P.R. China
| | - Li-Ping Zou
- Institute of Antibody Engineering, School of Biotechnology; Southern Medical University; Guangzhou; 510515; Guangdong; P.R. China
| | - Jing-Yuan Hou
- Institute of Antibody Engineering, School of Biotechnology; Southern Medical University; Guangzhou; 510515; Guangdong; P.R. China
| | - Ying-Song Wu
- Institute of Antibody Engineering, School of Biotechnology; Southern Medical University; Guangzhou; 510515; Guangdong; P.R. China
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27
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Ye Y, Hu Z, Liu J, Chen G, Zhou Y, Yu L. Detection of anticardiolipin antibody IgG by time-resolved fluoroimmunoassay. Clin Rheumatol 2012; 31:1339-45. [PMID: 22684164 DOI: 10.1007/s10067-012-2020-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2012] [Revised: 05/22/2012] [Accepted: 05/30/2012] [Indexed: 11/30/2022]
Abstract
In an effort to improve the quantitative detection of anticardiolipin antibodies (aCL) IgG so as to classify patients correctly as antiphospholipid syndrome (APS) positive, we developed a new immunoassay based on a sandwich time-resolved fluoroimmunoassay (TRFIA) using the complex of cardiolipin plus bovine β(2)GPI as antigen and Eu(3+)-labeled rabbit antihuman IgG as conjugate. The precision, sensitivity, specificity, and stability of the assay were evaluated, and comparison with the classical ELISA was also made. The aCL IgG TRFIA kit we established had a wider detectable range than three commercial ELISA ones from different manufacturers when a specimen was diluted, with strong positive result from 1:12.5 to 1:204,800. The average intra-assay and inter-assay CVs detected by the aCL IgG TRFIA was 3.14 and 3.70 %, respectively. The sensitivity was 0.1 GPL U/ml, and the clinical diagnostic specificity was 98 %. The established assay kit also behaved better in stability than the commercial ELISA ones. Additionally, the immunoassay we established correlated well with the ELISA, and the correlation coefficient was 0.975. We thus conclude that the TRFIA we developed for aCL IgG detection gives promise to a more sensitive and reliable diagnosis of APS and has potential value for large-scale screening programs.
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Affiliation(s)
- Yan Ye
- Affiliated Wuxi People's Hospital of Nanjing Medical University, Wuxi 214023, China
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28
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Zhang L, Wang Y, Ye Z, Jin D, Yuan J. New Class of Tetradentate β-Diketonate-Europium Complexes That Can Be Covalently Bound to Proteins for Time-Gated Fluorometric Application. Bioconjug Chem 2012; 23:1244-51. [DOI: 10.1021/bc300075t] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Affiliation(s)
- Lin Zhang
- State Key Laboratory of Fine
Chemicals, School of Chemistry, Dalian University of Technology, Dalian 116024, P. R. China
| | - Yanjiao Wang
- State Key Laboratory of Fine
Chemicals, School of Chemistry, Dalian University of Technology, Dalian 116024, P. R. China
| | - Zhiqiang Ye
- State Key Laboratory of Fine
Chemicals, School of Chemistry, Dalian University of Technology, Dalian 116024, P. R. China
| | - Dayong Jin
- MQ Photonics Centre, Faculty
of Science, Macquarie University, NSW 2109,
Sydney, Australia
| | - Jingli Yuan
- State Key Laboratory of Fine
Chemicals, School of Chemistry, Dalian University of Technology, Dalian 116024, P. R. China
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29
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Han YS, Quashie P, Mesplede T, Xu H, Mekhssian K, Fenwick C, Wainberg MA. A high-throughput assay for HIV-1 integrase 3'-processing activity using time-resolved fluorescence. J Virol Methods 2012; 184:34-40. [PMID: 22584270 DOI: 10.1016/j.jviromet.2012.05.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2011] [Revised: 04/26/2012] [Accepted: 05/03/2012] [Indexed: 01/08/2023]
Abstract
HIV-1 integrase (HIV-1 IN), a well-validated antiviral drug target, catalyzes multistep reactions to incorporate viral DNA into the genome of the host cell; these include both a 3'-processing (3'P) reaction and a strand transfer reaction. These enzymatic activities can be measured in vitro with short DNA oligonucleotides that mimic a single viral LTR DNA end and purified IN. A highly sensitive and reproducible time-resolved fluorescence (TRF)-based assay for HIV-1 IN 3'P activity is now reported. This assay was optimized with respect to time and concentrations of metal ions, substrate and enzyme. The assay has now been used successfully to measure HIV-1 IN 3'P activity and has been shown to detect the anti-IN activity of several known 3'P inhibition compounds accurately. This assay, which is amenable to high-throughput screening, will be useful for identification of additional HIV-1 IN 3'P inhibitors.
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Affiliation(s)
- Ying-Shan Han
- McGill University AIDS Centre, Lady Davis for Medical Research, Jewish General Hospital, Montreal, Quebec, Canada
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30
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Hildebrandt N, Geißler D. Semiconductor Quantum Dots as FRET Acceptors for Multiplexed Diagnostics and Molecular Ruler Application. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2012; 733:75-86. [DOI: 10.1007/978-94-007-2555-3_8] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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31
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Zhang H, Tian L, Zhang R, Ye Z, Yuan J. Preparation of visible-light-excited luminescence enhancement solutions for time-resolved luminescence detection of europium biolabel. Analyst 2012; 137:4502-8. [DOI: 10.1039/c2an35719d] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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32
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Végvári Á, Rezeli M, Sihlbom C, Häkkinen J, Carlsohn E, Malm J, Lilja H, Laurell T, Marko-Varga G. Molecular microheterogeneity of prostate specific antigen in seminal fluid by mass spectrometry. Clin Biochem 2011; 45:331-8. [PMID: 22209970 DOI: 10.1016/j.clinbiochem.2011.11.018] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2011] [Revised: 10/28/2011] [Accepted: 11/14/2011] [Indexed: 11/28/2022]
Abstract
OBJECTIVES Prostate specific antigen (PSA) is a widely used and clinically valuable marker for prostate disease. In order to enable the development of new PSA assays and progress the understanding of the biology of PSA we have analyzed PSA in seminal plasma. DESIGN AND METHODS PSA in seminal plasma from men attending a fertility clinic and healthy controls was analyzed using SDS-PAGE, Western blotting and mass spectrometry. RESULTS Using mass spectrometry, different forms of PSA could be identified in 1-9 bands seen on SDS-PAGE analysis of the respective sample. However, a majority of these molecular forms of PSA were not observed on Western blots. Enzymatic activity of PSA isoforms was demonstrated by sequencing data in zymogram gels. Multivariate analysis of clinical data revealed well-separated patient groups. CONCLUSIONS We demonstrated that PSA in seminal plasma occurs in several isoforms, yet not all were detectable using an antibody based clinical routine method. The heterogeneity of PSA expression might be of clinical significance, by an improved patient phenotyping.
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Affiliation(s)
- Ákos Végvári
- Clinical Protein Science & Imaging, Dept. of Measurement Technology and Industrial Electrical Engineering, Lund University, Lund, Sweden.
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33
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Zhu D, Chen Y, Jiang L, Geng J, Zhang J, Zhu JJ. Manganese-Doped ZnSe Quantum Dots as a Probe for Time-Resolved Fluorescence Detection of 5-Fluorouracil. Anal Chem 2011; 83:9076-81. [DOI: 10.1021/ac202101u] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Affiliation(s)
- Dong Zhu
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, People’s Republic of China
- College of Pharmacy, Nanjing University of Chinese Medicine, Nanjing 210046, People’s Republic of China
| | - Yun Chen
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, People’s Republic of China
| | - Liping Jiang
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, People’s Republic of China
| | - Jun Geng
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, People’s Republic of China
| | - Jianrong Zhang
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, People’s Republic of China
| | - Jun-Jie Zhu
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, People’s Republic of China
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Receptor-drug interaction: europium employment for studying the biochemical pathway of g-protein-coupled receptor activation. Met Based Drugs 2011; 2007:12635. [PMID: 18350113 PMCID: PMC2266097 DOI: 10.1155/2007/12635] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2007] [Accepted: 12/11/2007] [Indexed: 11/17/2022] Open
Abstract
In medicinal chemistry field, the biochemical pathways, involved in 7-transmembrane domains G-protein coupled receptors (GPCRs) activation, are commonly studied to establish the activity of ligands towards GPCRs. The most studied steps are the measurement of activated GTP-alpha subunit and stimulated intracellular cAMP. At the present, many researchers defined agonist or antagonist activity of potential GPCRs drugs employing [(35)S]GTPgammaS or [(3)H]cAMP as probes. Recently, the corresponding lanthanide labels Eu-GTP and Eu-cAMP as alternative to radiochemicals have been developed because they are highly sensitive, easy to automate, easily synthesized, they display a much longer shelf-life and they can be used in multilabel experiments. In the present review, the receptor-drug interaction by europium employment for studying the biochemical pathway of GPCR activation has been focused. Moreover, comparative studies between lanthanide label probes and the corresponding radiolabeled compounds have been carried out.
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35
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Bioinformatic strategies for unambiguous identification of prostate specific antigen in clinical samples. J Proteomics 2011; 75:202-10. [PMID: 21723425 DOI: 10.1016/j.jprot.2011.06.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2011] [Revised: 05/30/2011] [Accepted: 06/07/2011] [Indexed: 12/30/2022]
Abstract
Prostate specific antigen (PSA), as a widely used clinical biomarker in prostate cancer diagnostics, exists in multiple molecular forms. However, all of these forms might not be recognized in a given sample by the standard immunoassays. Therefore, we have investigated PSA isoforms, separated by size, using mass spectrometric analyses. The objective of these developments was to identify and specify the various forms of PSA. To optimize successful identification of different PSA forms, we have developed a bioinformatic strategy, consisting of high resolution MALDI-MS PMF and sequencing MS/MS data searches. To improve sequence-based identification, the recently introduced Proteios software environment was employed, allowing the combination of multiple database search engines in an automated manner. We could unambiguously identify PSA in clinical samples by all detectable tryptic peptides, which were found to be common in several isoforms.
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36
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Maindron N, Poupart S, Hamon M, Langlois JB, Plé N, Jean L, Romieu A, Renard PY. Synthesis and luminescence properties of new red-shifted absorption lanthanide(iii) chelates suitable for peptide and protein labelling. Org Biomol Chem 2011; 9:2357-70. [DOI: 10.1039/c0ob00832j] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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37
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Prakash A, Rezai T, Krastins B, Sarracino D, Athanas M, Russo P, Ross MM, Zhang H, Tian Y, Kulasingam V, Drabovich AP, Smith C, Batruch I, Liotta L, Petricoin E, Diamandis EP, Chan DW, Lopez MF. Platform for establishing interlaboratory reproducibility of selected reaction monitoring-based mass spectrometry peptide assays. J Proteome Res 2010; 9:6678-88. [PMID: 20945832 DOI: 10.1021/pr100821m] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Mass spectrometry (MS) is an attractive alternative to quantification of proteins by immunoassays, particularly for protein biomarkers of clinical relevance. Reliable quantification requires that the MS-based assays are robust, selective, and reproducible. Thus, the development of standardized protocols is essential to introduce MS into clinical research laboratories. The aim of this study was to establish a complete workflow for assessing the transferability and reproducibility of selected reaction monitoring (SRM) assays between clinical research laboratories. Four independent laboratories in North America, using identical triple-quadrupole mass spectrometers (Quantum Ultra, Thermo), were provided with standard protocols and instrumentation settings to analyze unknown samples and internal standards in a digested plasma matrix to quantify 51 peptides from 39 human proteins using a multiplexed SRM assay. The interlaboratory coefficient of variation (CV) was less than 10% for 25 of 39 peptides quantified (12 peptides were not quantified based upon hydrophobicity) and exhibited CVs less than 20% for the remaining peptides. In this report, we demonstrate that previously developed research platforms for SRM assays can be improved and optimized for deployment in clinical research environments.
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Affiliation(s)
- A Prakash
- Thermo Fisher Scientific, Biomarker research in Mass Spectrometry, Cambridge, Massachusettes, United States
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38
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Han C, Chen T, Zu L. Terbium chelate as donor label in time-resolved fluorescence energy transfer study of DNA hybridization. Chem Phys Lett 2010. [DOI: 10.1016/j.cplett.2010.10.028] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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39
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Krasnoperov LN, Marras SAE, Kozlov M, Wirpsza L, Mustaev A. Luminescent probes for ultrasensitive detection of nucleic acids. Bioconjug Chem 2010; 21:319-27. [PMID: 20085336 DOI: 10.1021/bc900403n] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Novel amino-reactive derivatives of lanthanide-based luminescent labels of enhanced brightness and metal retention were synthesized and used for the detection of cDNA oligonucleotides by molecular beacons. Time-resolved acquisition of the luminescent signal that occurs upon hybridization of the probe to the target enabled the avoidance of short-lived background fluorescence, markedly enhancing the sensitivity of detection, which was less than 1 pM. This value is about 50 to 100 times more sensitive than the level achieved with conventional fluorescence-based molecular beacons, and is 10 to 60 times more sensitive than previously reported for other lanthanide-based hybridization probes. These novel luminescent labels should significantly enhance the sensitivity of all type of nucleic acid hybridization probes, and could dramatically improve the detection limit of other biopolymers and small compounds that are used in a variety of biological applications.
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Affiliation(s)
- Lev N Krasnoperov
- Department of Chemistry and Environmental Sciences, New Jersey Institute of Technology, 151 Tiernan Hall, University Heights, Newark, New Jersey 07102, USA
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Armelao L, Quici S, Barigelletti F, Accorsi G, Bottaro G, Cavazzini M, Tondello E. Design of luminescent lanthanide complexes: From molecules to highly efficient photo-emitting materials. Coord Chem Rev 2010. [DOI: 10.1016/j.ccr.2009.07.025] [Citation(s) in RCA: 765] [Impact Index Per Article: 54.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Jiang L, Wu J, Wang G, Ye Z, Zhang W, Jin D, Yuan J, Piper J. Development of a Visible-Light-Sensitized Europium Complex for Time-Resolved Fluorometric Application. Anal Chem 2010; 82:2529-35. [DOI: 10.1021/ac100021m] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Lina Jiang
- State Key Laboratory of Fine Chemicals, Department of Chemistry, Dalian University of Technology, Dalian 116012, China, School of Chemistry and Chemical Engineering, Liaoning Normal University, Dalian 116029, China, and MQ Photonics Centre, Faculty of Science, Macquarie University, NSW 2109, Sydney, Australia
| | - Jing Wu
- State Key Laboratory of Fine Chemicals, Department of Chemistry, Dalian University of Technology, Dalian 116012, China, School of Chemistry and Chemical Engineering, Liaoning Normal University, Dalian 116029, China, and MQ Photonics Centre, Faculty of Science, Macquarie University, NSW 2109, Sydney, Australia
| | - Guilan Wang
- State Key Laboratory of Fine Chemicals, Department of Chemistry, Dalian University of Technology, Dalian 116012, China, School of Chemistry and Chemical Engineering, Liaoning Normal University, Dalian 116029, China, and MQ Photonics Centre, Faculty of Science, Macquarie University, NSW 2109, Sydney, Australia
| | - Zhiqiang Ye
- State Key Laboratory of Fine Chemicals, Department of Chemistry, Dalian University of Technology, Dalian 116012, China, School of Chemistry and Chemical Engineering, Liaoning Normal University, Dalian 116029, China, and MQ Photonics Centre, Faculty of Science, Macquarie University, NSW 2109, Sydney, Australia
| | - Wenzhu Zhang
- State Key Laboratory of Fine Chemicals, Department of Chemistry, Dalian University of Technology, Dalian 116012, China, School of Chemistry and Chemical Engineering, Liaoning Normal University, Dalian 116029, China, and MQ Photonics Centre, Faculty of Science, Macquarie University, NSW 2109, Sydney, Australia
| | - Dayong Jin
- State Key Laboratory of Fine Chemicals, Department of Chemistry, Dalian University of Technology, Dalian 116012, China, School of Chemistry and Chemical Engineering, Liaoning Normal University, Dalian 116029, China, and MQ Photonics Centre, Faculty of Science, Macquarie University, NSW 2109, Sydney, Australia
| | - Jingli Yuan
- State Key Laboratory of Fine Chemicals, Department of Chemistry, Dalian University of Technology, Dalian 116012, China, School of Chemistry and Chemical Engineering, Liaoning Normal University, Dalian 116029, China, and MQ Photonics Centre, Faculty of Science, Macquarie University, NSW 2109, Sydney, Australia
| | - James Piper
- State Key Laboratory of Fine Chemicals, Department of Chemistry, Dalian University of Technology, Dalian 116012, China, School of Chemistry and Chemical Engineering, Liaoning Normal University, Dalian 116029, China, and MQ Photonics Centre, Faculty of Science, Macquarie University, NSW 2109, Sydney, Australia
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Identification of prostate-specific antigen (PSA) isoforms in complex biological samples utilizing complementary platforms. J Proteomics 2010; 73:1137-47. [PMID: 20102753 DOI: 10.1016/j.jprot.2010.01.008] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2009] [Revised: 12/10/2009] [Accepted: 01/16/2010] [Indexed: 11/20/2022]
Abstract
Measurements of the prostate-specific antigen (PSA) levels in blood are widely used as diagnostic, predictive and prognostic marker of prostate disease. The selective detection of molecular forms of PSA can contribute clinically to meaningful enhancements of the conventional PSA-test. As it is plausible that an in-depth search for structural variants of PSA gene products may increase our ability to discriminate distinct patho-biological basis and stages of prostate diseases, we have developed a multi-step protocol comprising gel-based methods followed by mass spectrometric identification. Our current aim was to provide a comprehensive identification of PSA variants occurring in seminal fluid. We provide a proof-of-principle for this multiple step analytical approach to identify multiple PSA variants from complex biological samples that revealed distinct molecular characteristics. In addition, sequence-annotated protein bands in SDS-PAGE gels were compared to those detected by Western blots, and by monitoring the enzymatic activity in zymogram gels, using gelatin as a substrate. The high accuracy annotations were obtained by fast turnaround MALDI-Orbitrap analysis from excised and digested gel bands. Multiple PSA forms were identified utilizing a combination of MASCOT and SEQUEST search engines.
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Ray K, Chowdhury MH, Zhang J, Fu Y, Szmacinski H, Nowaczyk K, Lakowicz JR. Plasmon-controlled fluorescence towards high-sensitivity optical sensing. ADVANCES IN BIOCHEMICAL ENGINEERING/BIOTECHNOLOGY 2009; 116:29-72. [PMID: 19082931 PMCID: PMC6781866 DOI: 10.1007/10_2008_9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Fluorescence spectroscopy is widely used in chemical and biological research. Until recently most of the fluorescence experiments have been performed in the far-field regime. By far-field we imply at least several wavelengths from the fluorescent probe molecule. In recent years there has been growing interest in the interactions of fluorophores with metallic surfaces or particles. Near-field interactions are those occurring within a wavelength distance of an excited fluorophore. The spectral properties of fluorophores can dramatically be altered by near-field interactions with the electron clouds present in metals. These interactions modify the emission in ways not seen in classical fluorescence experiments. Fluorophores in the excited state can create plasmons that radiate into the far-field and fluorophores in the ground state can interact with and be excited by surface plasmons. These reciprocal interactions suggest that the novel optical absorption and scattering properties of metallic nanostructures can be used to control the decay rates, location, and direction of fluorophore emission. We refer to these phenomena as plasmon-controlled fluorescence (PCF). An overview of the recent work on metal-fluorophore interactions is presented. Recent research combining plasmonics and fluorescence suggest that PCF could lead to new classes of experimental procedures, novel probes, bioassays, and devices.
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Affiliation(s)
- K Ray
- Center for Fluorescence Spectroscopy, Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, 725 W Lombard St, Baltimore, MD, 21201, USA
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Hovinen J, Guy PM. Bioconjugation with Stable Luminescent Lanthanide(III) Chelates Comprising Pyridine Subunits. Bioconjug Chem 2008; 20:404-21. [DOI: 10.1021/bc800370s] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Jari Hovinen
- PerkinElmer Life and Analytical Sciences, Turku Site, POB 10, FI-20101 Turku, Finland, and PerkinElmer Incorporated, Winter Street, Waltham, Massachusetts 02451
| | - Pamela M. Guy
- PerkinElmer Life and Analytical Sciences, Turku Site, POB 10, FI-20101 Turku, Finland, and PerkinElmer Incorporated, Winter Street, Waltham, Massachusetts 02451
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Szmacinski H, Smith DS, Hanson MA, Kostov Y, Lakowicz JR, Rao G. A novel method for monitoring monoclonal antibody production during cell culture. Biotechnol Bioeng 2008; 100:448-57. [PMID: 18438872 PMCID: PMC2729163 DOI: 10.1002/bit.21795] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
We describe a new format for surface-based fluoroimmunoassays that allows detection of biomolecule interactions without separation steps. The bioactive layer was immobilized on the surface of a glass substrate covered with silver islands that provide optical amplification of the distinctive fluorescence signal from bound probes when compared to unbound probes. The technique used was phase-modulation fluorometry that allows sensitive detection of bound probes with a very short lifetime in the presence of excess free probes in solution. The new method was applied to assay monoclonal antibody production during cell culture. Excellent agreement was found between the new method and ELISA analysis of hybridoma cell culture samples. It is predicted that the near real time monitoring of protein products during bioprocessing will be possible with the described technology.
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Affiliation(s)
- Henryk Szmacinski
- Center for Fluorescence Spectroscopy, Department of Biochemistry and Molecular Biology, University of Maryland Baltimore, 725 W. Lombard St., Baltimore, Maryland 21201, USA.
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Sumitomo K, Ito T, Sasaki M, Yamaguchi Y. Hybridization Assay by Time-Resolved Capillary Gel Electrophoresis with a Lanthanide Chelate. Chromatographia 2008. [DOI: 10.1365/s10337-008-0571-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Identification of a potent synthetic FXR agonist with an unexpected mode of binding and activation. Proc Natl Acad Sci U S A 2008; 105:5337-42. [PMID: 18391212 DOI: 10.1073/pnas.0710981105] [Citation(s) in RCA: 75] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
The farnesoid X receptor (FXR), a member of the nuclear hormone receptor family, plays important roles in the regulation of bile acid and cholesterol homeostasis, glucose metabolism, and insulin sensitivity. There is intense interest in understanding the mechanisms of FXR regulation and in developing pharmaceutically suitable synthetic FXR ligands that might be used to treat metabolic syndrome. We report here the identification of a potent FXR agonist (MFA-1) and the elucidation of the structure of this ligand in ternary complex with the human receptor and a coactivator peptide fragment using x-ray crystallography at 1.9-A resolution. The steroid ring system of MFA-1 binds with its D ring-facing helix 12 (AF-2) in a manner reminiscent of hormone binding to classical steroid hormone receptors and the reverse of the pose adopted by naturally occurring bile acids when bound to FXR. This binding mode appears to be driven by the presence of a carboxylate on MFA-1 that is situated to make a salt-bridge interaction with an arginine residue in the FXR-binding pocket that is normally used to neutralize bound bile acids. Receptor activation by MFA-1 differs from that by bile acids in that it relies on direct interactions between the ligand and residues in helices 11 and 12 and only indirectly involves a protonated histidine that is part of the activation trigger. The structure of the FXR:MFA-1 complex differs significantly from that of the complex with a structurally distinct agonist, fexaramine, highlighting the inherent plasticity of the receptor.
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Sheng SL, Bao SH, Huang G, Wang LM. Development of time-resolved immunofluorometric assays for vascular endothelial growth factor and application on plasma of patients with gastric tumours. Clin Exp Immunol 2008; 151:459-66. [PMID: 18234057 DOI: 10.1111/j.1365-2249.2007.03548.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
A highly sensitive and accurate time-resolved immunofluorometric assay (TR-IFMA) has been developed, for the first time, to measure plasma vascular endothelial growth factor (VEGF) in patients with gastric tumours. A monoclonal anti-hVEGF antibody and a biotinylated anti-hVEGF antibody were used to develop a non-competitive 'sandwich'-type assay. Fluorescence can be measured by a time-resolved fluorometer after binding of europium (Eu)(3+)-labelled streptavidin to the biotinylated immunoglobulin. Plasma VEGF concentrations were measured by TR-IFMA in 92 healthy controls, in 36 benign stomach disease patients and in 92 gastric cancer patients before surgery. The association between plasma VEGF levels and clinicopathological features was evaluated. A standard curve for VEGF TR-IFMA has been developed with good sensitivity (0.37 pg/ml). Accuracy studies, specificity, parallelism and precision data were determined and all were found to be satisfactory. The validity of the VEGF assay was confirmed by the good correlation between the results obtained by TR-IFMA and commercial enzyme-linked immunosorbent assay (ELISA) (ELISA result = 1.862 + 0.953 (TR-IFMA result), r = 0.944]. The plasma levels of VEGF are higher in gastric cancer patients than in healthy controls. VEGF levels were associated significantly with the presence of distant metastases, as well as invasion depth of the tumour and tumour stage, but not with tumour location, tumour histology, differentiation or the presence of lymph node metastases. At the cut-off of 217.79 pg/ml, the diagnostic sensitivity, specificity and accuracy of the TR-IFMA were 40.2%, 93.7% and 69.9%, respectively. A highly sensitive and reliable TR-IFMA for VEGF has been developed. The determination of plasma VEGF levels may be clinically useful.
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Affiliation(s)
- S L Sheng
- Department of Nuclear Medicine, Renji Hopsital, and Institute of Clinical Nuclear Medicine, Shanghai JiaoTong University School of Medicine, Shanghai, China
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Järås K, Tajudin AA, Ressine A, Soukka T, Marko-Varga G, Bjartell A, Malm J, Laurell T, Lilja H. ENSAM: Europium Nanoparticles for Signal Enhancement of Antibody Microarrays on Nanoporous Silicon. J Proteome Res 2008; 7:1308-14. [DOI: 10.1021/pr700591j] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Kerstin Järås
- Department of Laboratory Medicine, Division of Clinical Chemistry, Lund University, Malmö University Hospital, Malmö, Sweden, Department of Electrical Measurement, Lund University, Lund, Sweden, Department of Biotechnology, University of Turku, Turku, Finland, Department of Analytical Chemistry, Lund University and AstraZeneca R&D Lund, Lund, Sweden, Department of Clinical Sciences, Division of Urological Cancers, Lund University, Malmö University Hospital, Malmö, Sweden, Departments of Clinical
| | - Asilah Ahmad Tajudin
- Department of Laboratory Medicine, Division of Clinical Chemistry, Lund University, Malmö University Hospital, Malmö, Sweden, Department of Electrical Measurement, Lund University, Lund, Sweden, Department of Biotechnology, University of Turku, Turku, Finland, Department of Analytical Chemistry, Lund University and AstraZeneca R&D Lund, Lund, Sweden, Department of Clinical Sciences, Division of Urological Cancers, Lund University, Malmö University Hospital, Malmö, Sweden, Departments of Clinical
| | - Anton Ressine
- Department of Laboratory Medicine, Division of Clinical Chemistry, Lund University, Malmö University Hospital, Malmö, Sweden, Department of Electrical Measurement, Lund University, Lund, Sweden, Department of Biotechnology, University of Turku, Turku, Finland, Department of Analytical Chemistry, Lund University and AstraZeneca R&D Lund, Lund, Sweden, Department of Clinical Sciences, Division of Urological Cancers, Lund University, Malmö University Hospital, Malmö, Sweden, Departments of Clinical
| | - Tero Soukka
- Department of Laboratory Medicine, Division of Clinical Chemistry, Lund University, Malmö University Hospital, Malmö, Sweden, Department of Electrical Measurement, Lund University, Lund, Sweden, Department of Biotechnology, University of Turku, Turku, Finland, Department of Analytical Chemistry, Lund University and AstraZeneca R&D Lund, Lund, Sweden, Department of Clinical Sciences, Division of Urological Cancers, Lund University, Malmö University Hospital, Malmö, Sweden, Departments of Clinical
| | - György Marko-Varga
- Department of Laboratory Medicine, Division of Clinical Chemistry, Lund University, Malmö University Hospital, Malmö, Sweden, Department of Electrical Measurement, Lund University, Lund, Sweden, Department of Biotechnology, University of Turku, Turku, Finland, Department of Analytical Chemistry, Lund University and AstraZeneca R&D Lund, Lund, Sweden, Department of Clinical Sciences, Division of Urological Cancers, Lund University, Malmö University Hospital, Malmö, Sweden, Departments of Clinical
| | - Anders Bjartell
- Department of Laboratory Medicine, Division of Clinical Chemistry, Lund University, Malmö University Hospital, Malmö, Sweden, Department of Electrical Measurement, Lund University, Lund, Sweden, Department of Biotechnology, University of Turku, Turku, Finland, Department of Analytical Chemistry, Lund University and AstraZeneca R&D Lund, Lund, Sweden, Department of Clinical Sciences, Division of Urological Cancers, Lund University, Malmö University Hospital, Malmö, Sweden, Departments of Clinical
| | - Johan Malm
- Department of Laboratory Medicine, Division of Clinical Chemistry, Lund University, Malmö University Hospital, Malmö, Sweden, Department of Electrical Measurement, Lund University, Lund, Sweden, Department of Biotechnology, University of Turku, Turku, Finland, Department of Analytical Chemistry, Lund University and AstraZeneca R&D Lund, Lund, Sweden, Department of Clinical Sciences, Division of Urological Cancers, Lund University, Malmö University Hospital, Malmö, Sweden, Departments of Clinical
| | - Thomas Laurell
- Department of Laboratory Medicine, Division of Clinical Chemistry, Lund University, Malmö University Hospital, Malmö, Sweden, Department of Electrical Measurement, Lund University, Lund, Sweden, Department of Biotechnology, University of Turku, Turku, Finland, Department of Analytical Chemistry, Lund University and AstraZeneca R&D Lund, Lund, Sweden, Department of Clinical Sciences, Division of Urological Cancers, Lund University, Malmö University Hospital, Malmö, Sweden, Departments of Clinical
| | - Hans Lilja
- Department of Laboratory Medicine, Division of Clinical Chemistry, Lund University, Malmö University Hospital, Malmö, Sweden, Department of Electrical Measurement, Lund University, Lund, Sweden, Department of Biotechnology, University of Turku, Turku, Finland, Department of Analytical Chemistry, Lund University and AstraZeneca R&D Lund, Lund, Sweden, Department of Clinical Sciences, Division of Urological Cancers, Lund University, Malmö University Hospital, Malmö, Sweden, Departments of Clinical
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