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Campo JJ, Romeis E, Oberai A, Pablo JV, Hung C, Teng AA, Shandling AD, Phan A, Haynes AM, Giacani L. A novel pan-proteome array for high-throughput profiling of the humoral response to Treponema pallidum. iScience 2024; 27:110618. [PMID: 39262771 PMCID: PMC11387709 DOI: 10.1016/j.isci.2024.110618] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2024] [Revised: 06/08/2024] [Accepted: 07/26/2024] [Indexed: 09/13/2024] Open
Abstract
Given the resurgence of syphilis, research endeavors to improve current assays for serological diagnosis and management of this disease are a priority. A proteome-scale platform for high-throughput profiling of the humoral response to Treponema pallidum (T. pallidum) proteins during infection could identify antigens suitable to ameliorate the performance and capabilities of treponemal tests for syphilis. Additionally, because infection-induced immunity is partially protective, profiling the response to T. pallidum outer membrane proteins (OMPs) could help select vaccine candidates. Therefore, we developed a pan-proteome array (PPA) based on the Nichols and SS14 strain complete proteomes and used it to define the immunoglobulin M (IgM) and IgG humoral response to T. pallidum proteins in sera collected longitudinally from long-term infected rabbits and from rabbits that were infected, treated, and re-infected. We identified antigens that could facilitate early diagnosis and immunity to a core set of OMP that could explain protection upon reinfection.
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Affiliation(s)
| | - Emily Romeis
- Department of Medicine, Division of Allergy and Infectious Diseases, University of Washington, Seattle, WA, USA
| | | | | | | | | | | | - Amber Phan
- Department of Medicine, Division of Allergy and Infectious Diseases, University of Washington, Seattle, WA, USA
| | - Austin M Haynes
- Department of Medicine, Division of Allergy and Infectious Diseases, University of Washington, Seattle, WA, USA
| | - Lorenzo Giacani
- Department of Medicine, Division of Allergy and Infectious Diseases, University of Washington, Seattle, WA, USA
- Department of Global Health, University of Washington, Seattle, WA, USA
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Silva ÂAO, Lima AA, Vasconcelos LCM, Almeida RA, Freitas NEM, Oliva TA, de Carvalho Ribeiro da Silva MF, Marchini FK, Zanchin NIT, de Siqueira IC, Santos FLN. Evaluating the diagnostic accuracy of TpN17 and TmpA recombinant proteins in syphilis detection: a phase II study. Front Microbiol 2024; 15:1348437. [PMID: 38476951 PMCID: PMC10929016 DOI: 10.3389/fmicb.2024.1348437] [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: 12/02/2023] [Accepted: 02/06/2024] [Indexed: 03/14/2024] Open
Abstract
Syphilis is a sexually transmitted infection (STI) caused by the spiral bacterium Treponema pallidum. Diagnosis is based on epidemiology, clinical and serology, but serodiagnosis is challenging because distinct clinical forms of the infection may influence serological performance. Several recombinant Treponema pallidum-proteins have already been tested for syphilis diagnosis and they are critical to achieve high accuracy in serological testing. A total of 647 samples were included in the study: 180 T. pallidum-positive samples, 191 T. pallidum-negative samples and 276 sera from individuals infected with unrelated diseases. The diagnostic potential was validated by analysis of ROC curves. For the indirect ELISA, TpN17 (100%) and TmpA (99%) showed excellent AUC values. Sensitivity values were 97.2% for TpN17 and 90.6% for TmpA, while specificity was 100% for both molecules. According to the clinical phase, TmpA ranged from 84% to 97%, with the highest value for secondary syphilis. TpN17 was 100% sensitive for the primary and secondary stages and 93.2% for recent latent syphilis. All clinical phases achieved 100% specificity. Accuracy values showed that TmpA (> 95%) and TpN17 (> 98%) presented high diagnostic accuracy for all clinical stages of syphilis. Cross-reactivity was only observed in one sample positive for Chagas disease (1.5%), when TpN17 was evaluated. On the other hand, TmpA showed reactivity for two samples positive for Chagas disease (3.1%), one sample positive for HBV (1.25%), two samples positive for HIV (9.5%) and one sample positive for HTLV (1.6%). The TmpA antigen's performance was evaluated in multiple studies for syphilis diagnosis, corroborating our findings. However, TpN17 sensitivity values have ranged in other studies. According to clinical stages of the infection, our findings obtained close performance values.
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Affiliation(s)
- Ângelo Antônio Oliveira Silva
- Advanced Public Health Laboratory, Gonçalo Moniz Institute (IGM) Foundation Oswaldo Cruz (Fiocruz-BA), Salvador, Brazil
- Salvador University (UNIFACS), Salvador, Brazil
| | - Ayla Araújo Lima
- Advanced Public Health Laboratory, Gonçalo Moniz Institute (IGM) Foundation Oswaldo Cruz (Fiocruz-BA), Salvador, Brazil
| | | | - Rosângela Andrade Almeida
- Advanced Public Health Laboratory, Gonçalo Moniz Institute (IGM) Foundation Oswaldo Cruz (Fiocruz-BA), Salvador, Brazil
| | - Natália Erdens Maron Freitas
- Advanced Public Health Laboratory, Gonçalo Moniz Institute (IGM) Foundation Oswaldo Cruz (Fiocruz-BA), Salvador, Brazil
| | | | | | - Fabricio Klerynton Marchini
- Molecular Biology Institute of Paraná, Curitiba, Brazil
- Laboratory for Applied Science and Technology in Health, Carlos Chagas Institute (ICC) Oswaldo Cruz Foundation (Fiocruz-PR), Curitiba, Brazil
| | - Nilson Ivo Tonin Zanchin
- Structural Biology and Protein Engineering Laboratory, Carlos Chagas Institute (ICC) Oswaldo Cruz Foundation (Fiocruz-PR), Curitiba, Brazil
- Integrated Translational Program in Chagas Disease from Fiocruz (Fio-Chagas), Oswaldo Cruz Foundation (Fiocruz-RJ), Rio de Janeiro, Brazil
| | - Isadora Cristina de Siqueira
- Integrated Translational Program in Chagas Disease from Fiocruz (Fio-Chagas), Oswaldo Cruz Foundation (Fiocruz-RJ), Rio de Janeiro, Brazil
- Laboratory of Investigation in Global Health and Neglected Diseases, Gonçalo Moniz Institute (IGM) Oswaldo Cruz Foundation (FIOCRUZ-BA), Salvador, Brazil
| | - Fred Luciano Neves Santos
- Advanced Public Health Laboratory, Gonçalo Moniz Institute (IGM) Foundation Oswaldo Cruz (Fiocruz-BA), Salvador, Brazil
- Integrated Translational Program in Chagas Disease from Fiocruz (Fio-Chagas), Oswaldo Cruz Foundation (Fiocruz-RJ), Rio de Janeiro, Brazil
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Haynes AM, Konda KA, Romeis E, Siebert J, Vargas SK, Reyes Diaz M, Phan A, Caceres CF, Giacani L, Klausner JD. Evaluation of a minimal array of Treponema pallidum antigens as biomarkers for syphilis diagnosis, infection staging, and response to treatment. Microbiol Spectr 2024; 12:e0346623. [PMID: 38095465 PMCID: PMC10782976 DOI: 10.1128/spectrum.03466-23] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Accepted: 11/27/2023] [Indexed: 01/13/2024] Open
Abstract
IMPORTANCE This manuscript explores the host humoral response to selected antigens of the syphilis agent during infection to evaluate their potential use as diagnostic tests and markers for treatment.
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Affiliation(s)
- Austin M. Haynes
- Department of Medicine, Division of Allergy and Infectious Diseases, Harborview Medical Center, University of Washington, Seattle, Washington, USA
| | - Kelika A. Konda
- Division of Infectious Disease, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California, USA
- Center for Interdisciplinary Studies in Sexuality, AIDS and Society, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Emily Romeis
- Department of Medicine, Division of Allergy and Infectious Diseases, Harborview Medical Center, University of Washington, Seattle, Washington, USA
| | | | - Silver K. Vargas
- Center for Interdisciplinary Studies in Sexuality, AIDS and Society, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Michael Reyes Diaz
- Division of Infectious Disease, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California, USA
| | - Amber Phan
- Department of Medicine, Division of Allergy and Infectious Diseases, Harborview Medical Center, University of Washington, Seattle, Washington, USA
| | - Carlos F. Caceres
- Division of Infectious Disease, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California, USA
| | - Lorenzo Giacani
- Department of Medicine, Division of Allergy and Infectious Diseases, Harborview Medical Center, University of Washington, Seattle, Washington, USA
- Department of Global Health, Harborview Medical Center, University of Washington, Seattle, Washington, USA
| | - Jeffrey D. Klausner
- Keck School of Medicine, University of Southern California, Los Angeles, California, USA
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Silva ÂAO, de Oliveira UD, Vasconcelos LDCM, Foti L, Leony LM, Daltro RT, Leitolis A, Lima FWDM, Krieger MA, Zanchin NIT, Santos FLN. Performance of Treponema pallidum recombinant proteins in the serological diagnosis of syphilis. PLoS One 2020; 15:e0234043. [PMID: 32555593 PMCID: PMC7302711 DOI: 10.1371/journal.pone.0234043] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Accepted: 05/18/2020] [Indexed: 11/18/2022] Open
Abstract
Syphilis serodiagnosis is challenging because distinct clinical forms of the infection may influence serological performance and discordant results between tests make clinical decisions difficult. Several recombinant Treponema pallidum-proteins have already been tested for syphilis diagnosis and they are critical to achieve high accuracy in serological testing. Our aim was to assess the varied from performance of T. pallidum-recombinant proteins TmpA, TpN17 and TpN47 for syphilis serodiagnosis. The proteins were evaluated using sera of 338 T. pallidum-negative, 173 T. pallidum-positive individuals and 209 sera from individuals infected with unrelated diseases. The diagnostic potential was validated by analysis of ROC curves. In the liquid microarray analyses, the ROC curve varied from 99.0% for TmpA and TpN17 to 100% for TpN47. The sensitivity score yielded values of up to 90% for TpN17, 100% for TpN47 and 80.0% for TmpA. The lowest and highest specificity values were presented by TpN47 (91.9%) and TmpA antigens (100%), respectively. TpN47 showed the highest accuracy score (95.5%) among all the recombinant proteins assayed. For the ELISA, the ROC curve was 97.2%, 91.8% and 81.6% for TpN17, TmpA and TpN47, respectively. TpN17 and TmpA yielded a sensitivity of 69.9%, while TpN47 obtained a value of 53.8%. Specificity was almost 100% for all three proteins. No cross-reaction was observed for TpN17 in the serum samples from non-bacterial infections. Regarding leptospirosis-positive samples, cross-reactivity score was varied from 8.6 to 34.6%. This is most probably due to conservation of the epitopes in these proteins across bacteria. The use of recombinant proteins in immunoassays for syphilis diagnosis was showed provide greater reliability to results of the treponemal assays. Despite the low sensitivity, the proteins showed high diagnostic capacity due to the AUC values found. However, an improvement in sensitivity could be achieved when antigenic mixtures are evaluated.
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Affiliation(s)
| | | | | | - Leonardo Foti
- Carlos Chagas Institute, Oswaldo Cruz Foundation (Fiocruz-PR), Curitiba, Paraná, Brazil
| | - Leonardo Maia Leony
- Gonçalo Moniz Institute, Oswaldo Cruz Foundation (Fiocruz-BA), Salvador, Bahia, Brazil
| | - Ramona Tavares Daltro
- Gonçalo Moniz Institute, Oswaldo Cruz Foundation (Fiocruz-BA), Salvador, Bahia, Brazil
| | | | | | - Marco Aurélio Krieger
- Carlos Chagas Institute, Oswaldo Cruz Foundation (Fiocruz-PR), Curitiba, Paraná, Brazil
- Molecular Biology Institute of Paraná, Curitiba, Paraná, Brazil
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Tang J, Zhou L, Gao W, Cao X, Wang Y. Visual DNA microarrays for simultaneous detection of human immunodeficiency virus type-1 and Treponema pallidum coupled with multiplex asymmetric polymerase chain reaction. Diagn Microbiol Infect Dis 2009; 65:372-8. [PMID: 19765935 DOI: 10.1016/j.diagmicrobio.2009.07.017] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2009] [Revised: 06/25/2009] [Accepted: 07/13/2009] [Indexed: 11/17/2022]
Abstract
Based on gold label silver stain and coupled with multiplex asymmetric polymerase chain reaction (PCR) analysis, we developed the visual DNA microarray for simultaneous, sensitive, and specific detection of human immunodeficiency virus type-1 (HIV-1) and Treponema pallidum. The 5'-end amino-modified oligonucleotides were immobilized on glass surface, which were used as the capturing probes to bind the complement biotinylated target DNA. The gold-conjugated streptavidins were introduced to the microarray for specific binding to biotin. The black image of microarray spots, which were the result from the precipitation of silver onto nanogold particles and bound to streptavidins, was visualized and accounted as the detection of biotinylated target DNA. Multiplex asymmetric PCR products of HIV-1 and T. pallidum and Bacillus subtilis (used as positive control) were performed for preparing the abundant biotinylated single-stranded target DNA of which could affect detection efficiency and sensitivity of hybridization on microarray. One hundred sixty-nine clinical samples of HIV-1 and T. pallidum from infected patients were tested using the homemade DNA microarrays. The results were identical to those shown in the assays of ELISA and fluorescence quantitative real-time PCR. Our results demonstrate that we have developed the visual gene detection technique, which is of high sensitivity and specificity; it may have potential in clinical applications.
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Affiliation(s)
- Jingfeng Tang
- The State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan 430072, China
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6
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Sun AH, Mao YF, Hu Y, Sun Q, Yan J. Sensitive and specific ELISA coated by TpN15-TpN17-TpN47 fusion protein for detection of antibodies to Treponema pallidum. Clin Chem Lab Med 2009; 47:321-6. [PMID: 19676144 DOI: 10.1515/cclm.2009.071] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND We constructed an artificial fusion gene tpN15-17-47 and then used the prokaryotic expression fusion protein rTpN15-17-47 as the coated antigen to establish a new enzyme-linked immunosorbent assay (ELISA) for serological diagnosis of syphilis. METHODS tpN15, tpN17, and tpN47 genes were amplified separately by polymerase chain reaction (PCR) and then assembled into a fusion gene coding a trigeminy protein antigen by primer linking PCR. The target recombinant protein antigens rTpN15, rTpN17, rTpN-47, and rTpN15-17-47 were expressed and then purified antigens were immobilized on the surface of microplate wells for detecting Treponema pallidum-specific antibodies by ELISAs. RESULTS The relative positive rate of rTpN15-17-47-ELISA in 965 serum specimens of syphilis patients was 99.5%, which was higher than that of the T. pallidum hemagglutination assay (TPHA) (98.3%) (p<0.05) and much higher than that of the rTpN15-ELISA (83.1%), the rTpN17-ELISA (84.4%), the rTpN47-ELISA (82.1%), and the toluidine red unheated serum test (TRUST) (72.2%) (p<0.01). All the ELISAs and the TPHA in detecting serum specimens from 62 cases with systemic lupus erythematosus (SLE), 86 cases with rheumatic arthritis (RA), and 250 healthy cases were negative, but the TRUST was positive in five cases with SLE, seven cases with RA, and two healthy cases. CONCLUSIONS The rTpN15-17-47-ELISA is a sensitive and specific serological screening or a diagnostic method for syphilis in the clinical setting.
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Affiliation(s)
- Ai Hua Sun
- Faculty of Basic Medicine, Zhejiang Medical College, Zhejiang Hangzhou, PR China
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7
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de Lemos EA, Belém ZR, Santos A, Ferreira AW. Characterization of the Western blotting IgG reactivity patterns in the clinical phases of acquired syphilis. Diagn Microbiol Infect Dis 2007; 58:177-83. [PMID: 17350208 DOI: 10.1016/j.diagmicrobio.2006.12.024] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2006] [Revised: 12/08/2006] [Accepted: 12/16/2006] [Indexed: 11/19/2022]
Abstract
We standardized the Western blotting (WB) method for detecting Treponema pallidum IgG (Tp-IgG) antibodies in sera samples of patients with syphilis and correlated the reactivity profile of bands with the clinical phases of the disease. The WB Tp-IgG has 100% sensitivity and 99.5% specificity. The clinical phases of the disease were associated with the reactive bands from TpN15 to TpN47. Quantitative Venereal Disease Research Laboratories was used to assist the WB Tp-IgG analysis. In primary syphilis, the reaction intensity for the antigenic band TpN47 was usually more intense when compared with other clinical phase. In secondary and sometimes in early latent syphilis, antibodies reacted with high numbers of antigenic proteins of T. pallidum. In late latent syphilis, various bands became negative, but the TpN15 and TpN47 were reactive. In tertiary syphilis, we observed reactivity with the TpN15 band and low reactivity with the TpN47. We concluded that WB Tp-IgG could be used to confirm serologic tests and characterize clinical phases of syphilis.
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Affiliation(s)
- Elaine Antunes de Lemos
- Laboratório de Soroepidemiologia e Imunobiologia, Instituto de Medicina Tropical de São Paulo, Universidade de São Paulo, 05403-000, São Paulo, Brazil
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Sato NS, Suzuki T, Ueda T, Watanabe K, Hirata RDC, Hirata MH. Recombinant antigen-based immuno-slot blot method for serodiagnosis of syphilis. Braz J Med Biol Res 2004; 37:949-55. [PMID: 15264000 DOI: 10.1590/s0100-879x2004000700002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Three recombinant antigens of Treponema pallidum Nichols strain were fused with GST, cloned and expressed in Escherichia coli, resulting in high levels of GST-rTp47 and GST-rTp17 expression, and supplementation with arginine tRNA for the AGR codon was needed to obtain GST-rTp15 overexpression. Purified fusion protein yields were 1.9, 1.7 and 5.3 mg/l of cell culture for GST-rTp47, GST-rTp17 and GST-rTp15, respectively. The identities of the antigens obtained were confirmed by automated DNA sequencing using ABI Prism 310 and peptide mapping by Finningan LC/MS. These recombinant antigens were evaluated by immuno-slot blot techniques applied to 137 serum samples from patients with a clinical and laboratory diagnosis of syphilis (61 samples), from healthy blood donors (50 samples), individuals with sexually transmitted disease other than syphilis (3 samples), and from individuals with other spirochetal diseases such as Lyme disease (20 samples) and leptospirosis (3 samples). The assay had sensitivity of 95.1% (95% CI, 86.1 to 98.7%) and a specificity of 94.7% (95% CI, 87.0 to 98.7%); a stronger reactivity was observed with fraction rTp17. The immunoreactivity results showed that fusion recombinant antigens based-immuno-slot blot techniques are suitable for use in diagnostic assays for syphilis.
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Affiliation(s)
- N S Sato
- Seção de Sorologia, Divisão de Biologia Médica, Instituto Adolfo Lutz, São Paulo, SP, Brazil.
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Van Voorhis WC, Barrett LK, Lukehart SA, Schmidt B, Schriefer M, Cameron CE. Serodiagnosis of syphilis: antibodies to recombinant Tp0453, Tp92, and Gpd proteins are sensitive and specific indicators of infection by Treponema pallidum. J Clin Microbiol 2003; 41:3668-74. [PMID: 12904373 PMCID: PMC179844 DOI: 10.1128/jcm.41.8.3668-3674.2003] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Syphilis serodiagnosis relies on a combination of nonspecific screening tests (antilipoidal antibodies) and Treponema pallidum-specific tests (anti-T. pallidum antibodies). We studied a group of six recombinant T. pallidum antigens for their sensitivities and specificities with sera from individuals with syphilis (n = 43), relapsing fever (n = 8), Lyme disease (n = 8), and leptospirosis (n = 9) and from uninfected individuals (n = 15). Three recombinant proteins, Tp0155, Tp0483, and Tp0751, demonstrated sensitivity values that ranged from 28 to 42%. In contrast, three other recombinant proteins exhibited the following sensitivity and specificity values: Tp0453, 100% sensitivity and 100% specificity; Tp92 (Tp0326), 98% sensitivity and 97% specificity; and Gpd (Tp0257), 91% sensitivity and 93% specificity. Tp0453, Tp92, and Gpd also were recognized by sera from individuals with early primary syphilis that were nonreactive with the antilipoidal Venereal Disease Research Laboratory test. The reactivities of syphilis patient sera with Tp0453, Tp92, and Gpd were proportional to the titers of these sera with the treponemal test MHA-TP (microhemagglutination assay for T. pallidum). Thus, the recombinant T. pallidum antigens Tp0453, Tp92, and Gpd show promise as diagnostic antigens in the enzyme-linked immunosorbent assay-based assay.
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Affiliation(s)
- Wesley C Van Voorhis
- Departments of Medicine and Pathobiology, University of Washington, Seattle, Washington 98195, USA.
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Sambri V, Marangoni A, Eyer C, Reichhuber C, Soutschek E, Negosanti M, D'Antuono A, Cevenini R. Western immunoblotting with five Treponema pallidum recombinant antigens for serologic diagnosis of syphilis. CLINICAL AND DIAGNOSTIC LABORATORY IMMUNOLOGY 2001; 8:534-9. [PMID: 11329453 PMCID: PMC96096 DOI: 10.1128/cdli.8.3.534-539.2001] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Five immunodominant Treponema pallidum recombinant polypeptides (rTpN47, rTmpA, rTpN37, rTpN17, and rTpN15) were blotted onto strips, and 450 sera (200 from blood donors, 200 from syphilis patients, and 50 potentially cross-reactive) were tested to evaluate the diagnostic performance of recombinant Western blotting (recWB) in comparison with in-house whole-cell lysate antigen-based immunoblotting (wclWB) and T. pallidum hemagglutination (MHA-TP) for the laboratory diagnosis of syphilis. None of the serum specimens from blood donors or from potential cross-reactors gave a positive result when evaluated by recWB, wclWB, or MHA-TP. The evaluation of the immunoglobulin G immune response by recWB in sera from patients with different stages of syphilis showed that rTmpA was the most frequently identified antigen (95%), whereas only 41% of the specimens were reactive to rTpN37. The remaining recombinant polypeptides were recognized as follows: rTpN47, 92.5%; rTpN17, 89.5%; and rTpN15, 67.5%. The agreement between recWB and MHA-TP was 95.0% (100% with sera from patients with latent and late disease), and the concordance between wclWB and MHA-TP was 92.0%. The overall concordance between recWB and wclWB was 97.5% (100% with sera from patients with secondary and late syphilis and 94.6 and 98.6% with sera from patients with primary and latent syphilis, respectively). The overall sensitivity of recWB was 98.8% and the specificity was 97.1% with MHA-TP as the reference method. These values for sensitivity and specificity were slightly superior to those calculated for wclWB (sensitivity, 97.1%, and specificity, 96.1%). With wclWB as the standard test, the sensitivity and specificity of recWB were 98.9 and 99.3%, respectively. These findings suggest that the five recombinant polypeptides used in this study could be used as substitutes for the whole-cell lysate T. pallidum antigens and that this newly developed recWB test is a good, easy-to-use confirmatory method for the detection of syphilis antibodies in serum.
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Affiliation(s)
- V Sambri
- Section of Microbiology, DMCSS, University of Bologna, St. Orsola Hospital, Bologna, Italy
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Sambri V, Marangoni A, Simone MA, D'Antuono A, Negosanti M, Cevenini R. Evaluation of recomWell Treponema, a novel recombinant antigen-based enzyme-linked immunosorbent assay for the diagnosis of syphilis. Clin Microbiol Infect 2001; 7:200-5. [PMID: 11422242 DOI: 10.1046/j.1469-0691.2001.00232.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To evaluate the diagnostic performance of an enzyme immunosorbent assay (recomWell Treponema) for the diagnosis of syphilis. The novel recombinant antigens Tpn47, TpN17 and TpN15 were utilized. METHODS A total of 782 human serum specimens, belonging to four different categories (blood donors, n = 200; routine laboratory screening for syphilis, n = 400; syphilis patients, n = 122; potential cross-reactors, n = 60), were evaluated to compare the sensitivity and specificity of the recomWell Treponema kit with a standard whole Treponema pallidum cell lysate antigen-based ELISA (Syphilis Screening) and with micro-haemagglutination (MHA-TP). RESULTS The overall specificity and sensitivity of the recomWell Treponema IgG was 98.9% and 98.3%, respectively. The specificity and sensitivity of Syphilis Screening ELISA was 98.7% and 98.3%, respectively. The agreement between recomWell Treponema and Syphilis Screening was 100%, 97.8%, 95.9% and 95% among the blood donor specimens, screening samples, syphilis specimens and the potential cross-reactors, respectively. Values of concordance varying from 96.7% to 98.3% were found in the different groups of sera between recomWell Treponema and MHA-TP. In addition, recomWell Treponema demonstrated a good diagnostic performance when used to detect the IgM to T. pallidum. No false-positive sera were identified and, in 17/19 samples from primary infection, an IgM immune response was found. CONCLUSIONS recomWell Treponema was shown to be a highly specific and sensitive method in all stages of syphilis screening and it can be considered as alternative to other ELISA tests based on native antigen preparations.
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Affiliation(s)
- V Sambri
- Departments of Microbiology and Dermatology, DMCSS, University of Bologna, St Orsola Hospital, via Massarenti 9, 40138 Bologna, Italy
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