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Panferov VG, Zherdev AV, Dzantiev BB. Post-Assay Chemical Enhancement for Highly Sensitive Lateral Flow Immunoassays: A Critical Review. BIOSENSORS 2023; 13:866. [PMID: 37754100 PMCID: PMC10526817 DOI: 10.3390/bios13090866] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2023] [Revised: 08/15/2023] [Accepted: 08/23/2023] [Indexed: 09/28/2023]
Abstract
Lateral flow immunoassay (LFIA) has found a broad application for testing in point-of-care (POC) settings. LFIA is performed using test strips-fully integrated multimembrane assemblies containing all reagents for assay performance. Migration of liquid sample along the test strip initiates the formation of labeled immunocomplexes, which are detected visually or instrumentally. The tradeoff of LFIA's rapidity and user-friendliness is its relatively low sensitivity (high limit of detection), which restricts its applicability for detecting low-abundant targets. An increase in LFIA's sensitivity has attracted many efforts and is often considered one of the primary directions in developing immunochemical POC assays. Post-assay enhancements based on chemical reactions facilitate high sensitivity. In this critical review, we explain the performance of post-assay chemical enhancements, discuss their advantages, limitations, compared limit of detection (LOD) improvements, and required time for the enhancement procedures. We raise concerns about the performance of enhanced LFIA and discuss the bottlenecks in the existing experiments. Finally, we suggest the experimental workflow for step-by-step development and validation of enhanced LFIA. This review summarizes the state-of-art of LFIA with chemical enhancement, offers ways to overcome existing limitations, and discusses future outlooks for highly sensitive testing in POC conditions.
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Affiliation(s)
- Vasily G. Panferov
- A.N. Bach Institute of Biochemistry, Research Center of Biotechnology of the Russian Academy of Sciences, 119071 Moscow, Russia; (V.G.P.); (A.V.Z.)
- Department of Chemistry, York University, Toronto, ON M3J 1P3, Canada
| | - Anatoly V. Zherdev
- A.N. Bach Institute of Biochemistry, Research Center of Biotechnology of the Russian Academy of Sciences, 119071 Moscow, Russia; (V.G.P.); (A.V.Z.)
| | - Boris B. Dzantiev
- A.N. Bach Institute of Biochemistry, Research Center of Biotechnology of the Russian Academy of Sciences, 119071 Moscow, Russia; (V.G.P.); (A.V.Z.)
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2
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Sharma V, Choudhary S, Mankotia P, Kumari A, Sharma K, Sehgal R, Kumar V. Nanoparticles as fingermark sensors. Trends Analyt Chem 2021. [DOI: 10.1016/j.trac.2021.116378] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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3
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Kalimuthu K, Cha BS, Kim S, Park KS. Eco-friendly synthesis and biomedical applications of gold nanoparticles: A review. Microchem J 2020. [DOI: 10.1016/j.microc.2019.104296] [Citation(s) in RCA: 70] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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4
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Niehaus WL, Howlin RP, Johnston DA, Bull DJ, Jones GL, Calton E, Mavrogordato MN, Clarke SC, Thurner PJ, Faust SN, Stoodley P. Development of X-ray micro-focus computed tomography to image and quantify biofilms in central venous catheter models in vitro. MICROBIOLOGY-SGM 2016; 162:1629-1640. [PMID: 27384949 DOI: 10.1099/mic.0.000334] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Bacterial infections of central venous catheters (CVCs) cause much morbidity and mortality, and are usually diagnosed by concordant culture of blood and catheter tip. However, studies suggest that culture often fails to detect biofilm bacteria. This study optimizes X-ray micro-focus computed tomography (X-ray µCT) for the quantification and determination of distribution and heterogeneity of biofilms in in vitro CVC model systems.Bacterial culture and scanning electron microscopy (SEM) were used to detect Staphylococcus epidermidis ATCC 35984 biofilms grown on catheters in vitro in both flow and static biofilm models. Alongside this, X-ray µCT techniques were developed in order to detect biofilms inside CVCs. Various contrast agent stains were evaluated using energy-dispersive X-ray spectroscopy (EDS) to further optimize these methods. Catheter material and biofilm were segmented using a semi-automated matlab script and quantified using the Avizo Fire software package. X-ray µCT was capable of distinguishing between the degree of biofilm formation across different segments of a CVC flow model. EDS screening of single- and dual-compound contrast stains identified 10 nm gold and silver nitrate as the optimum contrast agent for X-ray µCT. This optimized method was then demonstrated to be capable of quantifying biofilms in an in vitro static biofilm formation model, with a strong correlation between biofilm detection via SEM and culture. X-ray µCT has good potential as a direct, non-invasive, non-destructive technology to image biofilms in CVCs, as well as other in vivo medical components in which biofilms accumulate in concealed areas.
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Affiliation(s)
- Wilmari L Niehaus
- National Centre for Advanced Tribology at Southampton (nCATS), Faculty of Engineering and the Environment (FEE), University of Southampton, UK.,Southampton NIHR Wellcome Trust Clinical Research Facility, University Hospital Southampton NHS Foundation Trust, Southampton, UK.,Southampton NIHR Biomedical Research Centre and NIHR Respiratory Biomedical Research Unit, University of Southampton and University Hospital Southampton NHS Foundation Trust, Southampton, UK.,Faculty of Medicine, University of Southampton and University Hospital Southampton NHS Foundation Trust, Southampton, UK
| | - Robert P Howlin
- Southampton NIHR Biomedical Research Centre and NIHR Respiratory Biomedical Research Unit, University of Southampton and University Hospital Southampton NHS Foundation Trust, Southampton, UK.,Centre for Biological Sciences, Faculty of Natural and Environmental Sciences and Institute for Life Sciences, University of Southampton, Southampton, UK
| | - David A Johnston
- Faculty of Medicine, University of Southampton and University Hospital Southampton NHS Foundation Trust, Southampton, UK.,Biomedical Imaging Unit, University Hospital Southampton NHS Foundation Trust, Southampton, UK
| | - Daniel J Bull
- Engineering Materials Research Group, FEE, University of Southampton, UK
| | - Gareth L Jones
- Centre for Hybrid Biodevices, Electronics and Computer Science, University of Southampton, UK
| | - Elizabeth Calton
- Southampton NIHR Wellcome Trust Clinical Research Facility, University Hospital Southampton NHS Foundation Trust, Southampton, UK
| | | | - Stuart C Clarke
- Faculty of Medicine, University of Southampton and University Hospital Southampton NHS Foundation Trust, Southampton, UK.,Southampton NIHR Biomedical Research Centre and NIHR Respiratory Biomedical Research Unit, University of Southampton and University Hospital Southampton NHS Foundation Trust, Southampton, UK
| | - Philipp J Thurner
- Bioengineering Science Research Group, FEE, University of Southampton, UK.,Institute of Lightweight Design and Structural Biomechanics, TU Wien, Vienna, Austria
| | - Saul N Faust
- Faculty of Medicine, University of Southampton and University Hospital Southampton NHS Foundation Trust, Southampton, UK.,Southampton NIHR Biomedical Research Centre and NIHR Respiratory Biomedical Research Unit, University of Southampton and University Hospital Southampton NHS Foundation Trust, Southampton, UK.,Southampton NIHR Wellcome Trust Clinical Research Facility, University Hospital Southampton NHS Foundation Trust, Southampton, UK
| | - Paul Stoodley
- National Centre for Advanced Tribology at Southampton (nCATS), Faculty of Engineering and the Environment (FEE), University of Southampton, UK.,Center for Microbial Interface Biology (CMIB), Departments of Microbial Infection and Immunity, and Orthopaedics, The Ohio State University, Columbus, OH, USA
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5
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CAFIERO G, PAPALE F, GRIMALDI A, ROSSO F, BARBARISI M, TORTORA C, MARINO G, BARBARISI A. Immunogold labelling in environmental scanning electron microscopy: applicative features for complementary cytological interpretation. J Microsc 2010; 241:83-93. [DOI: 10.1111/j.1365-2818.2010.03405.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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6
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Defibrotide prevents the activation of macrovascular and microvascular endothelia caused by soluble factors released to blood by autologous hematopoietic stem cell transplantation. Biol Blood Marrow Transplant 2010; 17:497-506. [PMID: 21126597 DOI: 10.1016/j.bbmt.2010.11.019] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2010] [Accepted: 11/22/2010] [Indexed: 11/20/2022]
Abstract
Endothelial activation and damage occur in association with autologous hematopoietic stem cell transplantation (HSCT). Several of the early complications associated with HSCT seem to have a microvascular location. Through the present study, we have characterized the activation and damage of endothelial cells of both macro (HUVEC) and microvascular (HMEC) origin, occurring early after autologous HSCT, and the potential protective effect of defibrotide (DF). Sera samples from patients were collected before conditioning (Pre), at the time of transplantation (day 0), and at days 7, 14, and 21 after autologous HSCT. Changes in the expression of endothelial cell receptors at the surface, presence and reactivity of extracellular adhesive proteins, and the signaling pathways involved were analyzed. The expression of ICAM-1 at the cell surface increased progressively in both HUVEC and HMEC. However, a more prothrombotic profile was denoted for HMEC, in particular at the time of transplantation (day 0), reflecting the deleterious effect of the conditioning treatment on the endothelium, especially at a microvascular location. Interestingly, this observation correlated with a higher increase in the expression of both tissue factor and von Willebrand factor on the extracellular matrix, together with activation of intracellular p38 MAPK and Akt. Previous exposure and continuous incubation of cells with DF prevented the signs of activation and damage induced by the autologous sera. These observations corroborate that conditioning treatment in autologous HSCT induces a proinflammatory and a prothrombotic phenotype, especially at a microvascular location, and indicate that DF has protective antiinflammatory and antithrombotic effects in this setting.
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Palomo M, Diaz-Ricart M, Carbo C, Rovira M, Fernandez-Aviles F, Escolar G, Eissner G, Holler E, Carreras E. The release of soluble factors contributing to endothelial activation and damage after hematopoietic stem cell transplantation is not limited to the allogeneic setting and involves several pathogenic mechanisms. Biol Blood Marrow Transplant 2009; 15:537-46. [PMID: 19361745 DOI: 10.1016/j.bbmt.2009.01.013] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2008] [Accepted: 01/15/2009] [Indexed: 01/16/2023]
Abstract
This study evaluated the relative impact of the intensity of the conditioning regimen and the alloreactivity in the endothelial dysfunction occurring after allogeneic hematopoietic stem cell transplantation (allo-HSCT). It involved a comparative analysis of the effect of incubating human umbilical vein endothelial cells (ECs) with serum samples from patients receiving autologous HSCT (auto-HSCT) or unrelated donor allo-HSCT. In both groups, blood samples were collected through a central line before conditioning (Pre), before transplantation (day 0), and at days 7, 14, and 21 after transplantation. Changes in the expression of EC receptors and adhesion proteins, adhesion of leukocytes and platelets under flow, and signaling pathways were analyzed. Endothelial activation and damage were observed in both groups, but with differing patterns. All markers of endothelial dysfunction demonstrated a progressive increase from day Pre to day 14 in the auto-HSCT group and exhibited 2 peaks of maximal expression (at days 0 and 21) in the allo-HSCT group. Both treatments induced a proinflammatory state (ie, expression of adhesion receptors, leukocyte adhesion, and p38 MAPK activation) and cell proliferation (ie, morphology and activation of ErK42/44). Prothrombotic changes (ie, von Willebrand factor expression and platelet adhesion) predominated after allo-HSCT, and a proapoptotic tendency (ie, activation of SAPK/JNK) was seen only in this group. These findings indicate that endothelial activation and damage after HSCT also occur in the autologous setting and affect macrovascular ECs. After the initial damage induced by the conditioning regimen, other factors, such as granulocyte colony-stimulating factor (G-CSF) toxicity, engraftment, and alloreactivity, may contribute to the endothelial damage seen during HSCT. Further studies are needed to explore the association between this endothelial damage and the vascular complications associated with HSCT.
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Affiliation(s)
- Marta Palomo
- Hemotherapy-Hemostasis Department, Centre de Diagnòstic Biomèdic, University of Barcelona, Barcelona, Spain
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8
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Kenzaka T, Ishidoshiro A, Yamaguchi N, Tani K, Nasu M. rRNA sequence-based scanning electron microscopic detection of bacteria. Appl Environ Microbiol 2005; 71:5523-31. [PMID: 16151145 PMCID: PMC1214627 DOI: 10.1128/aem.71.9.5523-5531.2005] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A new scanning electron microscopic method was developed for gaining both phylogenetic and morphological information about target microbes using in situ hybridization with rRNA-targeted oligonucleotide probes (SEM-ISH). Target cells were hybridized with oligonucleotide probes after gold labeling. Gold enhancement was used for amplification of probe signals from hybridized cells. The hybridized cells released a strong backscatter electron signal due to accumulation of gold atoms inside cells. SEM-ISH was applied to analyze bacterial community composition in freshwater samples, and bacterial cell counts determined by SEM-ISH with rRNA-targeted probes for major phyla within the domain Bacteria were highly correlated to those by fluorescent in situ hybridization (FISH). The bacterial composition on surface of river sediment particles before and after cell dispersion treatment by sonication was successfully revealed by SEM-ISH. Direct enumeration of bacterial cells on the surface of sonicated sediment particles by SEM-ISH demonstrated that members of Cytophaga-Flavobacterium existed tightly on the surface of particles. SEM-ISH allows defining the number and distribution of phylogenetically defined cells adherent to material surfaces, which is difficult in FISH, and it gives new insight into electron microscopic studies of microorganisms in their natural environment.
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Affiliation(s)
- Takehiko Kenzaka
- Graduate School of Pharmaceutical Sciences, Osaka University, 1-6 Yamada-oka, Suita, Osaka 565-0871, Japan
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9
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Mills E, Parker M, Wellner N, Toole G, Feeney K, Shewry P. Chemical imaging: the distribution of ions and molecules in developing and mature wheat grain. J Cereal Sci 2005. [DOI: 10.1016/j.jcs.2004.09.003] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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10
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Wang YF, Shen JT, Liu HH. Analytical performance of and real sample analysis with an HBV gene visual detection chip. J Virol Methods 2004; 121:79-84. [PMID: 15350736 DOI: 10.1016/j.jviromet.2004.06.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2003] [Revised: 05/19/2004] [Accepted: 06/07/2004] [Indexed: 11/27/2022]
Abstract
A novel hepatitis B virus (HBV) gene detection chip has been developed. The HBV-specific probes immobilized on glass slides were hybridized with polymerase chain reaction (PCR) products of different serum samples. The hybridization signal can be easily visualized upon a sandwich assay with nanoparticle amplification. The analytical performance (e.g., specificity, sensitivity, and accuracy) of this method has been evaluated. The chip-based detection method possesses a greater sensitivity and a better reproducibility than some of the conventional immunological or molecular biological methods (e.g., enzyme-linked immunosorbent assay, ELISA) and is simple, cost-effective, and highly selective.
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Affiliation(s)
- Ye-Fu Wang
- College of Life Sciences, Wuhan University, Wuhan 430072, PR China.
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11
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Brandner JM, Kief S, Grund C, Rendl M, Houdek P, Kuhn C, Tschachler E, Franke WW, Moll I. Organization and formation of the tight junction system in human epidermis and cultured keratinocytes. Eur J Cell Biol 2002; 81:253-63. [PMID: 12067061 DOI: 10.1078/0171-9335-00244] [Citation(s) in RCA: 219] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Occludin and several proteins of the claudin family have been identiried in simple epithelia and in endothelia as major and structure-determining transmembrane proteins clustered in the barrier-forming tight junctions (TJ), where they are associated with a variety of TJ plaque proteins, including protein ZO-1. To examine whether TJ also occur in the squamous stratified epithelium of the interfollicular human epidermis we have applied several microscopic and biochemical techniques. Using RT-PCR techniques, we have identiried mRNAs encoding protein ZO-1, occludin and claudins 1, 4, 7, 8, 11, 12, and 17 in both tissues, skin and cultured keratinocytes, whereas claudins i and 10 have only been detected in skin tissue. By immunocytochemistry we have localized claudin-1, occludin and protein ZO-1 in distinct plasma membrane structures representing cell-cell attachment zones. While claudin-1 occurs in plasma membranes of all living cell layers, protein ZO-1 is concentrated in or even restricted to the uppermost layers, and occludin is often detected only in the stratum granulosum. Using electron microscopy, typical TJ structures ("kissing points") as well as some other apparently related junctional structures have been detected in the stratum granulosum, interspersed between desmosomes. Modes and patterns of TJ formation have also been studied in experimental model systems, e.g., during wound healing and stratification as well as in keratinocyte cultures during Ca2+-induced stratification. We conclude that the epidermis contains in the stratum granulosum a continuous zonula occludens-equivalent structure with typical TJ morphology and molecular composition, characterized by colocalization of occludin, claudins and TJ plaque proteins. In addition, cell-cell contact structures and certain TJ proteins can also be detected in other epidermal cell layers in specific cell contacts. The pattern of formation and possible functions of epidermal TJ and related structures are discussed.
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Affiliation(s)
- Johanna M Brandner
- Department of Dermatology and Venerology, University Hospital Hamburg-Eppendorf, Germany.
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12
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Shapiro A, Mullins JT. Hyphal tip growth in Achlya bisexualis. I. Distribution of 1,3-β-glucans in elongating and non-elongating regions of the wall. Mycologia 2002. [DOI: 10.1080/15572536.2003.11833232] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
| | - J. Thomas Mullins
- Department of Botany, PO Box 118526, University of Florida, Gainesville, Florida 32611-8526
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13
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Shapiro A, Mullins JT. Hyphal tip growth in Achlya bisexualis. II. Distribution of cellulose in elongating and non-elongating regions of the wall. Mycologia 2002. [DOI: 10.1080/15572536.2003.11833233] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
| | - J. Thomas Mullins
- Department of Botany, PO Box 118526, University of Florida, Gainesville, Florida 32611-8526
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González-García MB, Costa-García A. Silver electrodeposition catalyzed by colloidal gold on carbon paste electrode: application to biotin-streptavidin interaction monitoring. Biosens Bioelectron 2001; 15:663-70. [PMID: 11213227 DOI: 10.1016/s0956-5663(00)00111-1] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
A new electrochemical method to monitor biotin-streptavidin interaction on carbon paste electrode, based on silver electrodeposition catalyzed by colloidal gold, was investigated. Silver reduction potential changed when colloidal gold was attached to an electrode surface through the biotin-streptavidin interaction. Thus, the direct reduction of silver ions on the electrode surface could be avoided and therefore, they were only reduced to metallic silver on the colloidal gold particle surface, forming a shell around these particles. When an anodic scan was performed, this shell of silver was oxidized and an oxidation process at + 0.08 V was recorded in NH3 1.0 M. Biotinylated albumin was adsorbed on the pretreated electrode surface. This modified electrode was immersed in colloidal gold-streptavidin labeled solutions. The carbon paste electrode was then activated in adequate medium (NaOH 0.1 M and H2SO4 0.1 M) to remove proteins from the electrode surface while colloidal gold particles remained adsorbed on it. Then, a silver electrodeposition at -0.18 V for 2 min and anodic stripping voltammetry were carried out in NH3 1.0 M containing 2.0 x 10(-5) M of silver lactate. An electrode surface preparation was carried out to obtain a good reproducibility of the analytical signal (5.3%), using a new electrode for each experiment. In addition, a sequential competitive assay was carried out to determine streptavidin. A linear relationship between peak current and logarithm of streptavidin concentration from 2.25 x 10(-15) to 2.24 x 10(-12) M and a limit of detection of 2.0 x 10(15) M were obtained.
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Affiliation(s)
- M B González-García
- Departamento de Química Física y Analítica, Universidad de Oviedo, Asturias, Spain
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15
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Ito Y, Otsuki Y. Localization of apoptotic cells in the human epidermis by an in situ DNA nick end-labeling method using confocal reflectant laser microscopy. J Histochem Cytochem 1998; 46:783-6. [PMID: 9603792 DOI: 10.1177/002215549804600613] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
We describe an immunohistochemical method that allows the detection of apoptotic cells in human epidermis by use of confocal laser reflectance and antibody-immunogold-silver complexes. For this purpose, the site of free 3'-OH DNA ends was detected by the reflectance from heavy metal products (anti-digoxigenin antibody-immunogold-silver complexes) instead of 3, 3'-diaminobenzidine (DAB) reaction products in the conventional in situ nick end-labeling of DNA strand breaks (ISEL) technique. Localization of double-stranded DNA was demonstrated by the autofluorescence of methyl green. The ISEL technique using confocal reflectant laser microscopy (CRLM) clearly showed the most intense reflectance in the nuclei of granular cells, in contrast to only a weaker reflectance in those of basal cells. On the other hand, the extent of autofluorescence of methyl green was significantly more intense in the nuclei of basal cells and showed a reciprocal relation to that of the reflectance. Therefore, granular cells were most prone to apoptosis and did not contain double-stranded DNA, as indicated by the lack of stainability with methyl green. In addition, this method demonstrating the simultaneous localization of both free 3'-OH DNA ends and double-stranded DNA proved to have a wide range of applications, including the study of other DNA autolytic processes.
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Affiliation(s)
- Y Ito
- Department of Anatomy and Biology, Osaka Medical College, Osaka, Japan
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Herter P, Laube G, Gronczewski J, Minuth WW. Silver-enhanced colloidal-gold labelling of rabbit kidney collecting-duct cell surfaces imaged by scanning electron microscopy. J Microsc 1993; 171:107-15. [PMID: 7692067 DOI: 10.1111/j.1365-2818.1993.tb03364.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The luminal cell surfaces of rabbit kidney cortical collecting-duct cells were labelled with peanut lectin (PNA) and investigated by scanning electron microscopy. Labelling was performed either on 20-microns-thick cryostat sections from prefixed and cryoprotected rabbit kidney tissue or on cultured collecting-duct epithelium using biotinylated PNA and a 6-nm colloidal-gold-coupled antibody against biotin. Colloidal-gold labels were detected at low magnification (2000-4000x) using silver enhancement. Coating with chromium allowed simultaneous imaging of both cell-surface morphology and labelling topography in the backscattered electron imaging mode. Our results show that PNA binding is specific for a subtype of intercalated cells equipped with microvilli on the luminal surface. The presented method promises to be useful for the identification of specific cell types in heterogeneous tissues.
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Affiliation(s)
- P Herter
- Max-Planck-Institut für Molekulare Physiologie, Dortmund, Germany
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18
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Scopsi L, Pilotti S, Rilke F. Immunocytochemical localization and identification of members of the pancreatic polypeptide (PP)-fold family in human thyroid C cells and medullary carcinomas. REGULATORY PEPTIDES 1990; 30:89-104. [PMID: 2274682 DOI: 10.1016/0167-0115(90)90050-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
An increasing number of regulatory peptides not coded by the calcitonin genes are known to occur in the thyroid C cells. We have now carried out light and electron microscopic immunocytochemical analyses on specimens of normal human thyroids and medullary carcinomas to establish the occurrence of members of the PP-PYY-NPY family in the C cell system. By means of site-directed immunocytochemistry we provide the first evidence that a molecule closely related to proNPY is present in normal and pathologic C cells, and is co-stored with calcitonin in the cytoplasmic dense-core granules. Preliminary observations also suggest that high levels of expression of NPY-gene products help to define a subset of tumours with a less aggressive behaviour.
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Affiliation(s)
- L Scopsi
- Division of Anatomic Pathology and Cytology, Istituto Nazionale per lo Studio e la Cura dei Tumori, Milan, Italy
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19
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Peschke T, Wollweber L, Gabert A, Augsten K, Stracke R. Effect of different fixatives on Con A surface receptors of mouse peritoneal macrophages. HISTOCHEMISTRY 1990; 93:443-6. [PMID: 2323960 DOI: 10.1007/bf00315865] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The effects of glutaraldehyde, formaldehyde, or osmium tetroxide fixation on the number of labeled Con A surface receptors on mouse peritoneal macrophages were compared. Gold-labeled Con A receptors were found to be isolatedly arranged and evenly distributed on cell surfaces independent of the fixative used. Only cells preincubated with Con A and subsequently fixed by osmium tetroxide showed arrangement of labeled receptors in clusters. Significant differences were found in the number of Con A receptors per cell depending on the fixative used. The fluorescence intensity of FITC-Con A staining was detected spectrophotometrically, the characteristic X-rays of gold-labeled Con A receptors were determined by means of electron beam-induced X-ray microanalysis. The experimental results obtained both at light and electron microscopic level pointed to formaldehyde being the best fixative also for this purpose.
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Affiliation(s)
- T Peschke
- GDR Academy of Sciences, Central Institute of Microbiology and Experimental Therapy, DDR, Jena
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20
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Arias J, Scopsi L, Fischer JA, Larsson LI. Light- and electron-microscopical localization of calcitonin, calcitonin gene-related peptide, somatostatin and C-terminal gastrin/cholecystokinin immunoreactivities in rat thyroid. HISTOCHEMISTRY 1989; 91:265-72. [PMID: 2567289 DOI: 10.1007/bf00493000] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/28/2023]
Abstract
Parafollicular C cells of the rat thyroid contain several immunoreactive peptides including calcitonin (CT), calcitonin gene-related peptide (CGRP), somatostatin and a C-terminal gastrin/CCK immunoreactive epitope as shown at the light- and electron-microscopical levels. Adult thyroid C cells are strongly immunoreactive to CT and most of the cells also react strongly with CGRP antisera and weakly with a gastrin/CCK antiserum. The latter antiserum may cross-react with CGRP. This cross-reactivity probably only occurs at very high concentrations of CGRP observed in adult thyroid C cells, but not in intrathyroidal CGRP-containing nerves, nor in early neonatal C cells. In neonatal rats, somatostatin immunoreactive C cells are numerous and most of these cells are also CT and CGRP immunoreactive. In contrast, only few C cells display somatostatin immunoreactivity in adult rat thyroids. Sequential staining experiments revealed that some thyroidal C cells simultaneously express all four types of immunoreactivity. At the electron microscopical level, all of these immunoreactivities were observed in secretory granules of C cells. Double- and triple-staining experiments, moreover, documented that some peptides are co-localized in the same granules.
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Affiliation(s)
- J Arias
- Unit of Histochemistry, University Institute of Pathology, Copenhagen, Denmark
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