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Ogongo P, Nyakundi RK, Chege GK, Ochola L. The Road to Elimination: Current State of Schistosomiasis Research and Progress Towards the End Game. Front Immunol 2022; 13:846108. [PMID: 35592327 PMCID: PMC9112563 DOI: 10.3389/fimmu.2022.846108] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2021] [Accepted: 03/21/2022] [Indexed: 12/14/2022] Open
Abstract
The new WHO Roadmap for Neglected Tropical Diseases targets the global elimination of schistosomiasis as a public health problem. To date, control strategies have focused on effective diagnostics, mass drug administration, complementary and integrative public health interventions. Non-mammalian intermediate hosts and other vertebrates promote transmission of schistosomiasis and have been utilized as experimental model systems. Experimental animal models that recapitulate schistosomiasis immunology, disease progression, and pathology observed in humans are important in testing and validation of control interventions. We discuss the pivotal value of these models in contributing to elimination of schistosomiasis. Treatment of schistosomiasis relies heavily on mass drug administration of praziquantel whose efficacy is comprised due to re-infections and experimental systems have revealed the inability to kill juvenile schistosomes. In terms of diagnosis, nonhuman primate models have demonstrated the low sensitivity of the gold standard Kato Katz smear technique. Antibody assays are valuable tools for evaluating efficacy of candidate vaccines, and sera from graded infection experiments are useful for evaluating diagnostic sensitivity of different targets. Lastly, the presence of Schistosomes can compromise the efficacy of vaccines to other infectious diseases and its elimination will benefit control programs of the other diseases. As the focus moves towards schistosomiasis elimination, it will be critical to integrate treatment, diagnostics, novel research tools such as sequencing, improved understanding of disease pathogenesis and utilization of experimental models to assist with evaluating performance of new approaches.
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Affiliation(s)
- Paul Ogongo
- Division of Experimental Medicine, Department of Medicine, University of California, San Francisco, San Francisco, CA, United States.,Department of Tropical and Infectious Diseases, Institute of Primate Research, Nairobi, Kenya
| | - Ruth K Nyakundi
- Department of Tropical and Infectious Diseases, Institute of Primate Research, Nairobi, Kenya
| | - Gerald K Chege
- Primate Unit & Delft Animal Centre, South African Medical Research Council, Cape Town, South Africa.,Department of Pathology, University of Cape Town, Cape Town, South Africa
| | - Lucy Ochola
- Department of Tropical and Infectious Diseases, Institute of Primate Research, Nairobi, Kenya.,Department of Environmental Health, School of Behavioural and Lifestyle Sciences, Faculty of Health Sciences, Nelson Mandela University, Gqeberha, South Africa
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2
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Rodpai R, Sadaow L, Boonroumkaew P, Phupiewkham W, Thanchomnang T, Limpanont Y, Chusongsang P, Sanpool O, Ohmae H, Yamasaki H, Intapan PM, Maleewong W. Comparison of point-of-care test and enzyme-linked immunosorbent assay for detection of immunoglobulin G antibodies in the diagnosis of human schistosomiasis japonica. Int J Infect Dis 2021; 107:47-52. [PMID: 33864916 DOI: 10.1016/j.ijid.2021.04.039] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2021] [Revised: 04/10/2021] [Accepted: 04/12/2021] [Indexed: 11/18/2022] Open
Abstract
OBJECTIVE Schistosomiasis japonica is an important helminthic disease in Asia. Sensitive and accurate diagnostic tools are indispensable for clinical diagnosis, screening infection and monitoring its control. In this study, we developed an immunochromatographic test (Sj-ICT) to detect anti-Schistosoma japonicum immunoglobulin G antibodies in human sera. METHODS Somatic extract from adult S. japonicum was used as an antigen. The Sj-ICT was developed and optimized as a point-of-care test. All 214 human serum samples were evaluated for diagnostic usefulness and comparison with an enzyme-linked immunosorbent assay (ELISA). RESULTS The diagnostic sensitivity, specificity, positive and negative predictive values, and accuracy of the Sj-ICT were 90.8%, 87.9%, 86.4%, 91.9% and 89.3%, respectively. For ELISA the values were respectively 91.8%, 87.9%, 86.5%, 92.7% and 89.7%. The concordance between both methods was 86.4 % (Cohen's kappa value = 0.729). CONCLUSIONS The immunochromatographic test kit developed can support clinical diagnosis and large-scale surveys in endemic areas without requiring additional facilities or ancillary supplies.
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Affiliation(s)
- Rutchanee Rodpai
- Department of Parasitology and Excellence in Medical Innovation, and Technology Research Group, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand; Mekong Health Science Research Institute, Khon Kaen University, Khon Kaen, Thailand
| | - Lakkhana Sadaow
- Department of Parasitology and Excellence in Medical Innovation, and Technology Research Group, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand; Mekong Health Science Research Institute, Khon Kaen University, Khon Kaen, Thailand
| | - Patcharaporn Boonroumkaew
- Department of Parasitology and Excellence in Medical Innovation, and Technology Research Group, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand; Mekong Health Science Research Institute, Khon Kaen University, Khon Kaen, Thailand
| | - Weeraya Phupiewkham
- Department of Parasitology and Excellence in Medical Innovation, and Technology Research Group, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand; Mekong Health Science Research Institute, Khon Kaen University, Khon Kaen, Thailand
| | - Tongjit Thanchomnang
- Mekong Health Science Research Institute, Khon Kaen University, Khon Kaen, Thailand; Faculty of Medicine, Mahasarakram University, Mahasarakram, Thailand
| | - Yanin Limpanont
- Applied Malacology Laboratory, Department of Social and Environmental Medicine, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Phiraphol Chusongsang
- Applied Malacology Laboratory, Department of Social and Environmental Medicine, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Oranuch Sanpool
- Department of Parasitology and Excellence in Medical Innovation, and Technology Research Group, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand; Mekong Health Science Research Institute, Khon Kaen University, Khon Kaen, Thailand.
| | - Hiroshi Ohmae
- Department of Parasitology, National Institute of Infectious Diseases, Tokyo 162-8640, Japan; Department of Tropical Medicine and Parasitology, Dokkyo Medical University, Tochigi 321-0293, Japan
| | - Hiroshi Yamasaki
- Department of Parasitology, National Institute of Infectious Diseases, Tokyo 162-8640, Japan
| | - Pewpan M Intapan
- Department of Parasitology and Excellence in Medical Innovation, and Technology Research Group, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand; Mekong Health Science Research Institute, Khon Kaen University, Khon Kaen, Thailand
| | - Wanchai Maleewong
- Department of Parasitology and Excellence in Medical Innovation, and Technology Research Group, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand; Mekong Health Science Research Institute, Khon Kaen University, Khon Kaen, Thailand
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3
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El Saftawy EA. Validity of urine-CCA cassette test and indirect haem-agglutination assay (IHA) in the detection of schistosomiasis- mansoni infection relative to microscopic examination. J Parasit Dis 2021; 45:285-292. [PMID: 33746416 DOI: 10.1007/s12639-020-01303-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Accepted: 10/27/2020] [Indexed: 12/12/2022] Open
Abstract
Several immunodiagnostic assays have been commercially presented over the last years as easy diagnostic methods for schistosomiasis using serum or urine samples. The performance of immunochromatographic test (ICT) and indirect hemagglutination assay (IHA) was validated in the identification of active schistosomiasis infection. Detection of circulating cathodic antigen (CCA) of the parasite in urine samples and anti-Schistosoma antibodies in serum using ICT (Urine-CCA Cassette test) and IHA respectively. Proved diagnosis of Schistosoma mansoni infection was defined by the sum of positive results from microscopic examination (Gold standard) and Kato-Katz method. Out of 173 (mean age, 45 ± 10 years; 70 from Giza, 103 from different Egyptian governorates), 9 4 adult patients were infected. Urine-CCA cassette test despite showing high specificity (91.14%) it was of low sensitivity (23.40%). PPVs was 75.86% and NPV was 50.00% and diagnostic accuracy of 54.34%. The IHA showed a sensitivity of 57.45% and specificity of 48.10%. PPVs was 56.84% whereas NPVs was 48.72%. As for diagnostic accuracy, it was 53.18%. Urine-CCA Cassette test had lower sensitivity than expected for detection of circulating antigen and the IHA kit is generally more expensive than microscopic examination and Urine-CCA cassette test with low sensitivity and specificity. On the basis of this diagnostic performance none of the two tested immune-assays can be a sole tool in the principal diagnosis of active schistosomiasis infections.
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Affiliation(s)
- Enas A El Saftawy
- Medical Parasitology Department, Faculty of Medicine, Cairo University, Cairo, Egypt.,Medical Parasitology Department, Faculty of Medicine, Armed Forces College of Medicine, Cairo, Egypt
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Ogongo P, Kariuki TM, Wilson RA. Diagnosis of schistosomiasis mansoni: an evaluation of existing methods and research towards single worm pair detection. Parasitology 2018; 145:1355-66. [PMID: 29506583 DOI: 10.1017/S0031182018000240] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The inadequacy of current diagnostics for the detection of low worm burdens in humans means that schistosomiasis mansoni is more widespread than previously acknowledged. With the inception of mass drug treatment programmes aimed at disease elimination and the advent of human vaccine trials, the need for more sensitive diagnostics is evident. In this review, we evaluate the merits and limitations of the principal diagnostic methods, namely detection of eggs in faeces; anti-schistosome antibodies in serum; parasite-derived proteins and glycans in serum or urine; parasite DNA in blood, faeces or urine. Only in the baboon model, where actual worm burden is determined by portal perfusion, have faecal smear and circulating antigen methods been calibrated, and shown to have thresholds of detection of 10-19 worm pairs. There is scope for improvement in all the four methods of detection, e.g. the identification of single targets for host antibodies to improve the specificity of enzyme linked immunosorbent assay. Despite recent advances in the definition of the schistosome secretome, there have been no comprehensive biomarker investigations of parasite products in the urine of infected patients. Certainly, the admirable goal of eliminating schistosomiasis will not be achieved unless individuals with low worm burdens can be diagnosed.
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Beltrame A, Guerriero M, Angheben A, Gobbi F, Requena-Mendez A, Zammarchi L, Formenti F, Perandin F, Buonfrate D, Bisoffi Z. Accuracy of parasitological and immunological tests for the screening of human schistosomiasis in immigrants and refugees from African countries: An approach with Latent Class Analysis. PLoS Negl Trop Dis 2017; 11:e0005593. [PMID: 28582412 PMCID: PMC5472324 DOI: 10.1371/journal.pntd.0005593] [Citation(s) in RCA: 66] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2017] [Revised: 06/15/2017] [Accepted: 04/24/2017] [Indexed: 12/17/2022] Open
Abstract
Background Schistosomiasis is a neglected infection affecting millions of people, mostly living in sub-Saharan Africa. Morbidity and mortality due to chronic infection are relevant, although schistosomiasis is often clinically silent. Different diagnostic tests have been implemented in order to improve screening and diagnosis, that traditionally rely on parasitological tests with low sensitivity. Aim of this study was to evaluate the accuracy of different tests for the screening of schistosomiasis in African migrants, in a non endemic setting. Methodology/Principal findings A retrospective study was conducted on 373 patients screened at the Centre for Tropical Diseases (CTD) in Negrar, Verona, Italy. Biological samples were tested with: stool/urine microscopy, Circulating Cathodic Antigen (CCA) dipstick test, ELISA, Western blot, immune-chromatographic test (ICT). Test accuracy and predictive values of the immunological tests were assessed primarily on the basis of the results of microscopy (primary reference standard): ICT and WB resulted the test with highest sensitivity (94% and 92%, respectively), with a high NPV (98%). CCA showed the highest specificity (93%), but low sensitivity (48%). The analysis was conducted also using a composite reference standard, CRS (patients classified as infected in case of positive microscopy and/or at least 2 concordant positive immunological tests) and Latent Class Analysis (LCA). The latter two models demonstrated excellent agreement (Cohen’s kappa: 0.92) for the classification of the results. In fact, they both confirmed ICT as the test with the highest sensitivity (96%) and NPV (97%), moreover PPV was reasonably good (78% and 72% according to CRS and LCA, respectively). ELISA resulted the most specific immunological test (over 99%). The ICT appears to be a suitable screening test, even when used alone. Conclusions The rapid test ICT was the most sensitive test, with the potential of being used as a single screening test for African migrants. Schistosomiasis is probably the most important of the neglected tropical diseases (NTD) caused by helminthes (worms). It is acquired bathing in freshwater in endemic areas. The life cycle is complex and involves freshwater snails. Schistosomiasis, caused by Schistosoma mansoni, S. haematobium and less frequently by other species, affects more than 200 million people, mostly in Africa, and may chronically cause irreversible damage of the liver (S. mansoni) or of the kidneys and the urinary tract, including cancer of the bladder (S. haematobium). As in chronic infections eggs of both species are often missed by microscopy of faeces and urine, with this retrospective study we evaluate the accuracy of different, alternative diagnostic tests, for the screening of schistosomiasis in African migrants and asylum seekers, of whom many thousands reach the Italian coast every year proceding from the most endemic areas. The most interesting finding of our study is that a rapid diagnostic test for antibody detection in blood, easy to use as a point-of-care tool, resulted the most sensitive of the five tests evaluated, and thus is very promising as a screening tool even when used without any additional test.
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Affiliation(s)
- Anna Beltrame
- Centre for Tropical Diseases, Ospedale Sacro Cuore Don Calabria, Negrar, Verona, Italy
| | | | - Andrea Angheben
- Centre for Tropical Diseases, Ospedale Sacro Cuore Don Calabria, Negrar, Verona, Italy
| | - Federico Gobbi
- Centre for Tropical Diseases, Ospedale Sacro Cuore Don Calabria, Negrar, Verona, Italy
| | - Ana Requena-Mendez
- Barcelona Institute for Global Health, ISGlobal-CRESIB, Universitat de Barcelona, Barcelona, Spain
| | - Lorenzo Zammarchi
- Infectious and Tropical Diseases Department, Azienda Ospedaliera Universitaria Careggi, Florence, Italy
| | - Fabio Formenti
- Centre for Tropical Diseases, Ospedale Sacro Cuore Don Calabria, Negrar, Verona, Italy
| | - Francesca Perandin
- Centre for Tropical Diseases, Ospedale Sacro Cuore Don Calabria, Negrar, Verona, Italy
| | - Dora Buonfrate
- Centre for Tropical Diseases, Ospedale Sacro Cuore Don Calabria, Negrar, Verona, Italy
- * E-mail:
| | - Zeno Bisoffi
- Centre for Tropical Diseases, Ospedale Sacro Cuore Don Calabria, Negrar, Verona, Italy
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Corstjens PL, De Dood CJ, Kornelis D, Fat EM, Wilson RA, Kariuki TM, Nyakundi RK, Loverde PT, Abrams WR, Tanke HJ, Van Lieshout L, Deelder AM, Van Dam GJ. Tools for diagnosis, monitoring and screening of Schistosoma infections utilizing lateral-flow based assays and upconverting phosphor labels. Parasitology 2014; 141:1841-55. [PMID: 24932595 DOI: 10.1017/S0031182014000626] [Citation(s) in RCA: 135] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The potential of various quantitative lateral flow (LF) based assays utilizing up-converting phosphor (UCP) reporters for the diagnosis of schistosomiasis is reviewed including recent developments. Active infections are demonstrated by screening for the presence of regurgitated worm antigens (genus specific polysaccharides), whereas anti-Schistosoma antibodies may indicate ongoing as well as past infections. The circulating anodic antigen (CAA) in serum or urine (and potentially also saliva) is identified as the marker that may allow detection of single-worm infections. Quantitation of antigen levels is a reliable method to study effects of drug administration, worm burden and anti-fecundity mechanisms. Moreover, the ratio of CAA and circulating cathodic antigen (CCA) is postulated to facilitate identification of either Schistosoma mansoni or Schistosoma haematobium infections. The UCP-LF assays allow simultaneous detection of multiple targets on a single strip, a valuable feature for antibody detection assays. Although antibody detection in endemic regions is not a useful tool to diagnose active infections, it gains potential when the ratio of different classes of antibody specific for the parasite/disease can be determined. The UCP-LF antibody assay format allows this type of multiplexing, including testing a linear array of up to 20 different targets. Multiple test spots would allow detection of specific antibodies, e.g. against different Schistosoma species or other pathogens as soil-transmitted helminths. Concluding, the different UCP-LF based assays for diagnosis of schistosomiasis provide a collection of tests with relatively low complexity and high sensitivity, covering the full range of diagnostics needed in control programmes for mapping, screening and monitoring.
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Abstract
There are innumerable clinical and pathological problems associated with schistosomiasis that have necessitated various control programs. Successful control would naturally depend on effective rapid diagnosis in the field. However, the overlapping distribution of urinary and intestinal schistosomiasis in hyperendemic areas calls for differential diagnosis. This study was aimed at producing anti-Schistosoma mansoni monoclonal antibodies (MAbs) for possible utilization in assays to detect antigens in the urine of infected persons. In order to raise antibodies to less immunogenic urinary parasite antigens, BALB/c mice were immunized with Schistosoma mansoni soluble worm antigens (Sm-SWA) while urinary proteins (Sm-UP(2)IP), isolated from infected human urine samples, was used as a final booster before cell fusion. Hybridoma cells were obtained by the fusion of mouse myeloma and spleen cells from the immunized mice, which were screened by microplate ELISA and then studied further to obtain anti-S. mansoni specific MAbs. The MAbs analyzed presented IgM isotypes. The reactivity of anti-S. mansoni MAbs with Sm-UP(2)IP, 13/43 (30.2%), MAbs showed stronger reactivity. It was observed that one of the MAbs cross-reacted with antigen associated with S. haematobium urinary antigen (Sh-UP(2)IP). Nine (9/13, 69.2%) MAbs recognized glycoprotein antigenic epitopes of Sm-UP(2)IP and Sm-SWA. On the other hand, 4/13 (30.8%) MAbs recognized carbohydrate antigenic epitopes. Band size of 8.9 kDa associated with Sm-UP(2)IP was detected by the 13 MAbs. With Sm-SWA, all the MAbs detected band sizes of 177.8 and 158.5 kDa. In addition, three MAbs recognized a 38.9 kDa band. The generation of anti-S. mansoni species-specific MAbs offers opportunities to develop a specific MAb-based diagnostic tool for use in the field to detect Schistosoma mansoni infection in Ghana.
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MESH Headings
- Animals
- Antibodies, Helminth/biosynthesis
- Antibodies, Helminth/immunology
- Antibodies, Monoclonal, Murine-Derived/biosynthesis
- Antibodies, Monoclonal, Murine-Derived/immunology
- Antibody Specificity
- Antigens, Helminth/immunology
- Blotting, Western
- Child
- Diagnosis, Differential
- Endemic Diseases
- Epitope Mapping
- Ghana/epidemiology
- Humans
- Hybridomas
- Immunoglobulin M/biosynthesis
- Immunoglobulin M/immunology
- Mice
- Mice, Inbred BALB C
- Prevalence
- Schistosoma mansoni/immunology
- Schistosomiasis mansoni/diagnosis
- Schistosomiasis mansoni/epidemiology
- Schistosomiasis mansoni/urine
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Affiliation(s)
- D Boamah
- Institute of Tropical Medicine, Nagasaki University, Sakamoto, Nagasaki City, Japan.
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Coulibaly JT, Knopp S, N'Guessan NA, Silué KD, Fürst T, Lohourignon LK, Brou JK, N'Gbesso YK, Vounatsou P, N'Goran EK, Utzinger J. Accuracy of urine circulating cathodic antigen (CCA) test for Schistosoma mansoni diagnosis in different settings of Côte d'Ivoire. PLoS Negl Trop Dis 2011; 5:e1384. [PMID: 22132246 DOI: 10.1371/journal.pntd.0001384] [Citation(s) in RCA: 110] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2011] [Accepted: 09/18/2011] [Indexed: 01/30/2023] Open
Abstract
Background Promising results have been reported for a urine circulating cathodic antigen (CCA) test for the diagnosis of Schistosoma mansoni. We assessed the accuracy of a commercially available CCA cassette test (designated CCA-A) and an experimental formulation (CCA-B) for S. mansoni diagnosis. Methodology We conducted a cross-sectional survey in three settings of Côte d'Ivoire: settings A and B are endemic for S. mansoni, whereas S. haematobium co-exists in setting C. Overall, 446 children, aged 8–12 years, submitted multiple stool and urine samples. For S. mansoni diagnosis, stool samples were examined with triplicate Kato-Katz, whereas urine samples were tested with CCA-A. The first stool and urine samples were additionally subjected to an ether-concentration technique and CCA-B, respectively. Urine samples were examined for S. haematobium using a filtration method, and for microhematuria using Hemastix dipsticks. Principal Findings Considering nine Kato-Katz as diagnostic ‘gold’ standard, the prevalence of S. mansoni in setting A, B and C was 32.9%, 53.1% and 91.8%, respectively. The sensitivity of triplicate Kato-Katz from the first stool and a single CCA-A test was 47.9% and 56.3% (setting A), 73.9% and 69.6% (setting B), and 94.2% and 89.6% (setting C). The respective sensitivity of a single CCA-B was 10.4%, 29.9% and 75.0%. The ether-concentration technique showed a low sensitivity for S. mansoni diagnosis (8.3–41.0%). The specificity of CCA-A was moderate (76.9–84.2%); CCA-B was high (96.7–100%). The likelihood of a CCA-A color reaction increased with higher S. mansoni fecal egg counts (odds ratio: 1.07, p<0.001). A concurrent S. haematobium infection or the presence of microhematuria did not influence the CCA-A test results for S. mansoni diagnosis. Conclusion/Significance CCA-A showed similar sensitivity than triplicate Kato-Katz for S. mansoni diagnosis with no cross-reactivity to S. haematobium and microhematuria. The low sensitivity of CCA-B in our study area precludes its use for S. mansoni diagnosis. We aimed to assess the accuracy of a commercially available rapid diagnostic test for the detection of an infection with the blood fluke Schistosoma mansoni in urine. In total, 446 school children from three different settings of south Côte d'Ivoire provided three stool and three urine samples. Stool samples were examined with the widely used Kato-Katz technique and analyzed with a microscope for S. mansoni eggs. Urine samples were examined with a filtration method for S. haematobium eggs and with a rapid diagnostic test for S. mansoni that is based on detecting circulating cathodic antigens (CCA). We used a commercially available test (designated CCA-A) and an experimental formulation (CCA-B). Examination of nine Kato-Katz thick smears per child revealed a prevalence of S. mansoni in the three settings of 32.9%, 53.1%, and 91.8%. The sensitivity of triplicate Kato-Katz from the first stool sample was comparable to a single CCA-A (47.9–94.2% vs. 56.3–89.6%), and significantly higher than the sensitivity of a single CCA-B test (10.4–75.0%). CCA-A showed a considerably lower specificity than CCA-B (76.9–84.2% vs. 96.7–100%). In the settings studied in south Côte d'Ivoire, the CCA-A test holds promise for the diagnosis of S. mansoni, whereas results with CCA-B were suboptimal.
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Balog CIA, Mayboroda OA, Wuhrer M, Hokke CH, Deelder AM, Hensbergen PJ. Mass spectrometric identification of aberrantly glycosylated human apolipoprotein C-III peptides in urine from Schistosoma mansoni-infected individuals. Mol Cell Proteomics 2010; 9:667-81. [PMID: 20071361 DOI: 10.1074/mcp.m900537-mcp200] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Schistosomiasis is a parasitic infection caused by Schistosoma flatworms, prime examples of multicellular parasites that live in the mammalian host for many years. Glycoconjugates derived from the parasite have been shown to play an important role in many aspects of schistosomiasis, and some of them are present in the circulation of the host. The aim of this study was to identify novel glycoconjugates related to schistosomiasis in urine of Schistosoma mansoni-infected individuals using a combination of glycopeptide separation techniques and in-depth mass spectrometric analysis. Surprisingly, we characterized a heterogeneous population of novel aberrantly O-glycosylated peptides derived from the C terminus of human apolipoprotein C-III (apoC-III) in urine of S. mansoni-infected individuals that were not detected in urine of non-infected controls. The glycan composition of these glycopeptides is completely different from what has been described previously for apoC-III. Most importantly, they lack sialylation and display a high degree of fucosylation. This study exemplifies the potential of mass spectrometry for the identification and characterization of O-glycopeptides without prior knowledge of either the glycan or the peptide sequence. Furthermore, our results indicate for the first time that as a result of S. mansoni infection the glycosylation of a host protein is altered.
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Affiliation(s)
- Crina I A Balog
- Department of Parasitology, Center of Infectious Diseases, Leiden University Medical Center, Leiden, The Netherlands.
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Peng SY, Tsaihong JC, Fan PC, Lee KM. Diagnosis of schistosomiasis using recombinant fructose-1,6-bisphosphate aldolase from a Formosan strain of Schistosoma japonicum. J Helminthol 2009; 83:211-8. [PMID: 19079948 DOI: 10.1017/S0022149X08147411] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Schistosoma japonicum obtained from Taiwan is a zoophilic strain that only infects domestic and small animals. Recombinant fructose-1,6-bisphosphate aldolase (FBPA) derived from this strain was used as an antigen in an enzyme-linked immunosorbent assay (ELISA) for the diagnosis of human schistosomiasis. The full-length DNA sequence of FBPA was found to be 1092 bp, encoding a protein of 363 amino acid residues, with a molecular mass of 39.6 kDa. A total of 120 participants were recruited from China and Taiwan to evaluate the diagnostic value of this recombinant protein. In these participants, 34 were found to be infected with S. japonicum, 16 with Ascaris lumbricoides, 15 with hookworm, 13 with Paragonimus westermani and 13 with Clonorchis sinensis, whereas 29 had no ova on faecal examination. Western blot analysis showed that the recombinant FBPA reacts strongly with schistosome ova-positive sera. The sensitivity and specificity of ELISA with FBPA were found to be 85.3% and 93.0%, respectively. These results indicate that FBPA derived from the Formosan strain of S. japonicum can be used for the diagnosis of human schistosomiasis.
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Abstract
In recent years, there has been an increase in cases of imported helminthiasis in Spain because of two complementary causes: immigration and international travel. Although the prevalence of helminthiasis is high in the immigrant population, the risk of transmission to the Spanish population is low. In this review, we provide clues to aid in the diagnosis of the helminthiasis, highlighting the geographic characteristics, clinical findings and analytical results of the most frequent types. The low sensitivity of the classic parasitological diagnostic test, mainly in tissue helminthiasis, is described. In addition, the advantages and limitations of the common serological methods for detecting related circulating antigens and antibodies are presented. Certain molecular methods used in the diagnosis of imported helminthiasis and the best strategies for screening of this condition are discussed.
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Affiliation(s)
- Javier Pardo
- Laboratorio de Inmunología Parasitaria y Molecular, CISET, Facultad de Farmacia, Universidad de Salamanca, España.
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Planchart S, Incani RN, Cesari IM. Preliminary characterization of an adult worm “vomit” preparation of Schistosoma mansoni and its potential use as antigen for diagnosis. Parasitol Res 2007; 101:301-9. [PMID: 17310394 DOI: 10.1007/s00436-007-0482-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2006] [Accepted: 01/24/2007] [Indexed: 11/30/2022]
Abstract
Schistosoma mansoni is a parasitic trematode of the portal-mesenteric veins with a closed-end intestine. Adult worms regurgitate their intestinal content after digestion, together with constituents of the lining gut. Some of these molecules circulate in the blood and are antigenic. We obtain a "vomit" preparation and preliminary evaluate its biochemical composition and antigenic capacity. The "vomit" preparation was obtained after changes in temperature and solutions of incubation of adult worms between 4 and 37 degrees C. Supernatant was assayed for protein, carbohydrate concentration and enzymatic activities associated to the intestine and to the worm tegument. The antigenicity of the product was evaluated using Western blot (WB) analysis against sera of experimentally infected mice, before and after drug cure, sera from people infected with S. mansoni and from individuals infected with other parasitoses. More carbohydrate than protein was detected in the preparations. Cysteine proteinase (CP), N-acetyl-beta-D: -glucosaminidase and alkaline phosphatase activities were detected. The latter enzyme activity is a marker of the tegument, suggesting that in spite of careful conditions used to avoid the presence of tegumental material, manipulation of the worms always resulted in the release of tegumental molecules. Cationic exchange chromatography was useful to separate various components of this "vomit" preparation, particularly enzymes responsible for CP activity. Two highly immunogenic and specific duplets were observed in the WB analysis, 31/32- and 38/40-kDa components, the former probably referring to the intestinal CPs Sm31/Sm32. None of the two duplets disappeared after successful chemotherapy during the time of evaluation in mice or humans.
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Affiliation(s)
- Sandra Planchart
- Departamento de Parasitología, Facultad de Ciencias de la Salud, Universidad de Carabobo, Valencia, Venezuela
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13
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Akhiani AA, Deelder AM, Månsson JE, Nilsson LA. Interaction of cholera toxin with three life-cycle stages of Schistosoma mansoni: adult worm, egg and cercaria. Scand J Immunol 2007; 65:48-53. [PMID: 17212766 DOI: 10.1111/j.1365-3083.2006.01868.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
We have previously reported that there is an immunological cross-reactivity between Schistosoma mansoni and cholera toxin (CT). In this study, using an immunofluorescence technique with anti-CT antibody, we provide further evidence for this cross-reactivity by demonstrating an antigen, localized in the tegument of S. mansoni adult worms which is cross-reactive with a CT antigen. Anti-CT antibodies also reacted with structures in S. mansoni cercariae and eggs. Additionally, CT itself was found to bind strongly to the gut of the adult worm, gut cells of cercaria and the egg shell. The binding of CT to the parasite was blocked when parasite sections were incubated with CT which had been incubated with the ganglioside GM1. Lipid extraction and isolation of gangliosides demonstrated the presence of GM1 in adult worms. For further analysis of CT-binding structures, the possible interaction of CT with two major schistosome gut antigens, circulating cathodic antigen (CCA) and circulating anodic antigen (CAA), was studied. We found that CT blocked the binding of anti-CCA antibody to the gut of adult worms and that anti-CCA blocked the binding of CT to the worm gut. These findings indicate that CT binds to CCA present in the gut of the parasite and thus has, in addition to GM1, a second binding specificity.
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Affiliation(s)
- A A Akhiani
- Department of Clinical Bacteriology, Clinical Virology and Infectious Diseases, Institute of Biomedicine, Göteborg University, Göteborg, Sweden
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14
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Pardo J, Carranza C, Turrientes MC, Pérez Arellano JL, López Vélez R, Ramajo V, Muro A. Utility of Schistosoma bovis adult worm antigens for diagnosis of human schistosomiasis by enzyme-linked immunosorbent assay and electroimmunotransfer blot techniques. Clin Diagn Lab Immunol 2005; 11:1165-70. [PMID: 15539523 PMCID: PMC524774 DOI: 10.1128/cdli.11.6.1165-1170.2004] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Immunodiagnostic methods based on the detection of antibodies continue to be the most effective and practical methods for the diagnosis of imported schistosomiasis. Schistosoma bovis is a species whose final natural hosts are bovines, ovines, caprines, and small wild ruminants. Different studies have demonstrated the analogies existing between S. bovis and other Schistosoma species which affect humans. The objective of this work was to evaluate the utility of S. bovis adult worm antigens (AWA) for the diagnosis of imported human schistosomiasis by enzyme-linked immunosorbent assay (ELISA) and electroimmunotransfer blotting (EITB) techniques. By detecting eggs, the ELISA for S. bovis AWA was able to definitively detect imported cases with a sensitivity of 94%. The specificity of the ELISA for S. bovis AWA was 97%. There were no differences between the results of the S. bovis AWA ELISA for patients infected with Schistosoma mansoni and those infected with Schistosoma haematobium. The EITB technique showed bands of 85, 37, and 20 kDa, which are characteristic of infections with Schistosoma spp. Specific bands to indicate infection by different species of Schistosoma have not been detected. The combined use of the ELISA for S. bovis AWA and EITB increased the global sensitivity of the study to 97%. Our findings suggest that the ELISA for S. bovis AWA is a useful test for the immunodiagnosis of imported schistosomiasis and that EITB for detecting S. bovis AWA permits the confirmation of diagnosis when the ELISA for S. bovis AWA is positive.
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Affiliation(s)
- J Pardo
- Laboratorio de Inmunología Parasitaria y Molecular, CISET, Facultad de Farmacia, Universidad de Salamanca, Avda. Campo Charro s/n 37007, Salamanca, Spain
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15
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Nyame AK, Kawar ZS, Cummings RD. Antigenic glycans in parasitic infections: implications for vaccines and diagnostics. Arch Biochem Biophys 2004; 426:182-200. [PMID: 15158669 DOI: 10.1016/j.abb.2004.04.004] [Citation(s) in RCA: 114] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2004] [Revised: 04/12/2004] [Indexed: 02/01/2023]
Abstract
Infections by parasitic protozoans and helminths are a major world-wide health concern, but no vaccines exist to the major human parasitic diseases, such as malaria, African trypanosomiasis, amebiasis, leishmaniasis, schistosomiasis, and lymphatic filariasis. Recent studies on a number of parasites indicate that immune responses to parasites in infected animals and humans are directed to glycan determinants within cell surface and secreted glycoconjugates and that glycoconjugates are important in host-parasite interactions. Because of the tremendous success achieved recently in generating carbohydrate-protein conjugate vaccines toward microbial infections, such as Haemophilus influenzae type b, there is renewed interest in defining parasite-derived glycans in the prospect of developing conjugate vaccines and new diagnostics for parasitic infections. Parasite-derived glycans are compelling vaccine targets because they have structural features that distinguish them from mammalian glycans. There have been exciting new developments in techniques for glycan analysis and the methods for synthesizing oligosaccharides by chemical or combined chemo-enzymatic approaches that now make it feasible to generate parasite glycans to test as vaccine candidates. Here, we highlight recent progress made in elucidating the immunogenicity of glycans from some of the major human and animal parasites, the potential for developing conjugate vaccines for parasitic infections, and the possible utilization of these novel glycans in diagnostics.
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Affiliation(s)
- A Kwame Nyame
- Department of Biochemistry and Molecular Biology, Oklahoma Center for Medical Glycobiology, University of Oklahoma Health Sciences Center, Biomedical Research Center, Room 417, 975 NE 10th Street, Oklahoma City, OK 73104, USA
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16
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Ribeiro de Jesus A, Araújo I, Bacellar O, Magalhães A, Pearce E, Harn D, Strand M, Carvalho EM. Human immune responses to Schistosoma mansoni vaccine candidate antigens. Infect Immun 2000; 68:2797-803. [PMID: 10768975 PMCID: PMC97490 DOI: 10.1128/iai.68.5.2797-2803.2000] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
To determine the naturally occurring immunological responses to the Schistosoma mansoni antigens paramyosin, IrV-5, Sm-23 (MAP-3), and triose phosphate isomerase (MAP-4), a total of 119 subjects from an area of endemicity for schistosomiasis, including "resistant" subjects (n = 17) were evaluated. Specific immunoglobulin G1 (IgG1), IgG2, IgG3, IgG4, and IgA levels for each of the antigens and the cytokine profile in culture supernatants from antigen-stimulated peripheral blood mononuclear cells (PBMC) were determined. Although all the subjects had a high degree of contaminated water exposure, their infection levels were variable (0 to 1,128 eggs/g of stool). There were direct correlations between infection levels and levels of SWAP- and paramyosin-specific IgG1 and IgG4 (P < 0.05). However, an inverse correlation between infection levels and specific IgG2 to IrV-5 (P < 0.01) was observed. The evaluation of the cytokine profile (interleukin 5 [IL-5], IL-10, gamma interferon [IFN-gamma], and tumor necrosis factor alpha) in response to these antigens showed inverse correlations between the degree of infection and IFN-gamma levels in PBMC supernatants stimulated with paramyosin (P < 0.05) and IrV-5 (P < 0.01). Additionally, inverse correlations between the degree of infection and IL-5 levels in MAP-3- and MAP-4-stimulated PBMC supernatants (P < 0.01) were found. Logistic regression analysis was performed to adjust the results of cytokine profile by age. IL-5 production in MAP-3-stimulated PBMC supernatants was associated with lower infection levels (odds ratio = 11.2 [95% confidence interval, 2.7 to 45.8]).
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Affiliation(s)
- A Ribeiro de Jesus
- Serviço de Imunologia, Hospital Universitário Prof. Edgard Santos, Universidade Federal da Bahia, Bahia, Brazil
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17
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Attallah AM, Ismail H, El Masry SA, Rizk H, Handousa A, El Bendary M, Tabll A, Ezzat F. Rapid detection of a Schistosoma mansoni circulating antigen excreted in urine of infected individuals by using a monoclonal antibody. J Clin Microbiol 1999; 37:354-7. [PMID: 9889217 PMCID: PMC84306 DOI: 10.1128/jcm.37.2.354-357.1999] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Schistosoma circulating antigens were used to indicate the infection intensity and to assess cure. An immunoglobulin G2a (IgG2a) mouse monoclonal antibody was used in a fast dot-enzyme-linked immunosorbent assay (ELISA; FDA) for rapid and simple diagnosis of schistosomiasis in the field. Seven hundred Egyptians were parasitologically examined for Schistosoma mansoni and other parasitic infections. A rectal biopsy was done as a "gold standard" for individuals showing no S. mansoni eggs in their feces. Egg counts were obtained by the Kato smear method for only 100 of 152 individuals with eggs in their feces. Specific anti-schistosome IgG antibodies were evaluated in sera by ELISA. Urine samples from the 700 individuals were tested by FDA for detection of the circulating antigen. The assay showed a sensitivity of 93% among 433 infected individuals and a specificity of 89% among 267 noninfected individuals. FDA showed the highest efficiency of antigen detection (91%) compared with the efficiency of antibody detection by ELISA (75%) and stool analysis (60%). In addition, FDA detected infected patients with 20 eggs/g of feces. Also, the sensitivity of FDA ranged from 90 to 94% among samples from patients with different clinical stages of schistosomiasis. All the assay steps can be completed within 30 min at room temperature for 96 urine samples. The monoclonal antibody identified a 74-kDa antigen in different antigenic extracts of S. mansoni and Schistosoma haematobium and in the urine of infected individuals. In addition, a 30-kDa degradation product was identified only in the urine samples. On the basis of these results, FDA should be used as a rapid tool for the sensitive and specific diagnosis of Schistosoma infection.
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Affiliation(s)
- A M Attallah
- Biotechnology Research Center, New Damietta City, Faculty of Medicine, Mansoura University, Mansoura, Egypt
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18
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Attallah AM, Ismail H, El Masry SA, Rizk H, Handousa A, El Bendary M, Tabll A, Ezzat F. Rapid detection of a Schistosoma mansoni circulating antigen excreted in urine of infected individuals by using a monoclonal antibody. J Clin Microbiol 1999; 37:354-7. [PMID: 9889217 DOI: 10.1128/JCM.37.2.354-357.1999] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Schistosoma circulating antigens were used to indicate the infection intensity and to assess cure. An immunoglobulin G2a (IgG2a) mouse monoclonal antibody was used in a fast dot-enzyme-linked immunosorbent assay (ELISA; FDA) for rapid and simple diagnosis of schistosomiasis in the field. Seven hundred Egyptians were parasitologically examined for Schistosoma mansoni and other parasitic infections. A rectal biopsy was done as a "gold standard" for individuals showing no S. mansoni eggs in their feces. Egg counts were obtained by the Kato smear method for only 100 of 152 individuals with eggs in their feces. Specific anti-schistosome IgG antibodies were evaluated in sera by ELISA. Urine samples from the 700 individuals were tested by FDA for detection of the circulating antigen. The assay showed a sensitivity of 93% among 433 infected individuals and a specificity of 89% among 267 noninfected individuals. FDA showed the highest efficiency of antigen detection (91%) compared with the efficiency of antibody detection by ELISA (75%) and stool analysis (60%). In addition, FDA detected infected patients with 20 eggs/g of feces. Also, the sensitivity of FDA ranged from 90 to 94% among samples from patients with different clinical stages of schistosomiasis. All the assay steps can be completed within 30 min at room temperature for 96 urine samples. The monoclonal antibody identified a 74-kDa antigen in different antigenic extracts of S. mansoni and Schistosoma haematobium and in the urine of infected individuals. In addition, a 30-kDa degradation product was identified only in the urine samples. On the basis of these results, FDA should be used as a rapid tool for the sensitive and specific diagnosis of Schistosoma infection.
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19
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Pereira e Silva Y, Secor E, Andrade MO, Katz N, Rabello A. Circulating antigens levels in different clinical forms of the Schistosoma mansoni infection. Mem Inst Oswaldo Cruz 1999; 94:83-6. [PMID: 10029916 DOI: 10.1590/s0074-02761999000100017] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
With the aim to evaluate the circulating cathodic antigen (CCA) levels in relation to the different clinical phases of Schistosoma sp. infection a sandwich ELISA using monoclonal antibody 5H11 was performed. The sera of three groups of 25 Brazilian patients with acute, intestinal and hepatosplenic forms of S. mansoni infection were tested and compared to a non-infected control group. Patients and control groups were matched for age and sex and the number of eggs per gram of feces was equally distributed among the three patient groups. Sensitivity of 100%, 72%, 52% of the assay was observed for the intestinal, hepatosplenic and acute toxemic groups respectively. The specificity was 100%. Intestinal and hepatosplenic groups presented CCA levels significantly higher in comparison to those observed for acute patients (F-ratio = 2,524; p = 0.000 and F-ratio = 6,314; p = 0.015 respectively). There was no significant difference of CCA serum levels between hepatosplenic and intestinal groups (F-ratio = 1,026; p = 0.316).
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Affiliation(s)
- Y Pereira e Silva
- Laboratório de Esquistossomose, Centro de Pesquisas René Rachou-Fiocruz, MG, Brasil
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20
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Abstract
The ideal diagnostic method for schistosomiasis detection seems to be still far from available. Paucity of egg output in low prevalence situations, low levels of circulating antigens in individuals with low intensity of infection and inadequate specificity of antibody detection systems outline pieces of a puzzle that challenges scientific efforts. Estimated prevalence, financial resources and operational reality must be taken into account when deciding the diagnostic method to be used. A combination of a screening step, using a fast strip test for antibody detection with a parasitological ratification step such as Kato-Katz repeated stool examination may serve as a diagnostic approach for a previously untreated low level endemic area. However, when eradication is the aim, and high financial investment is available, re-treatment may be based on the association between multiple stool examination and circulating antigen detection. Ethical aspects as well as cost-benefit rates between treatment and diagnosis approaches lead to the conclusion that in spite of the recent advances in simple administered and relatively safe drugs, treatment should only be performed when supported by appropriated diagnosis.
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Affiliation(s)
- A Rabello
- Centro de Pesquisas René Rachou-FIOCRUZ, Belo Horizonte, MG, Brasil.
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21
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Alarcón de Noya BA, Cesari IM, Losada S, Colmenares C, Balzán C, Hoebeke J, Noya O. Evaluation of alkaline phosphatase immunoassay and comparison with other diagnostic methods in areas of low transmission of schistosomiasis. Acta Trop 1997; 66:69-78. [PMID: 9227799 DOI: 10.1016/s0001-706x(97)00032-6] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The alkaline phosphatase immunoassay (APIA) is an antibody detection technique which permits the diagnosis of schistosomiasis using a butanolic extract preparation from adult worms. APIA has demonstrated high sensitivity and specificity in previous reports with well characterized human sera. Its potential as a diagnostic tool for epidemiological surveillance was assessed in comparison with three other diagnostic tests: stool examination, ELISA with soluble egg antigen (SEA) and the circumoval precipitin test (COPT). APIA was 100% specific in an area without Schistosoma mansoni transmission and had 89% sensitivity in an endemic area where 69% of the infected subjects excreted less than 100 eggs g of faeces. It was found to be less sensitive in children under 5 years of age who were positive by the COPT test. APIA can be applied as an initial screening test, based on its high sensitivity, specificity, absence of cross-reactivity with intestinal parasites and the fact that it is a technique suitable for use in epidemiological surveillance.
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Affiliation(s)
- B A Alarcón de Noya
- Sección de Biohelmintiasis, Universidád Central de Venezuela, Caracas, Venezuela.
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22
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Nibbeling HA, Van Etten L, Fillié YE, Deelder AM. Enhanced detection of Schistosoma circulating antigens by testing 1 ml urine samples using immunomagnetic beads. Acta Trop 1997; 66:85-92. [PMID: 9227801 DOI: 10.1016/s0001-706x(97)00039-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The potential advantage of increasing the sample volume for enhanced detection of two Schistosoma circulating antigens in urine has been evaluated. Two different, monoclonal antibody based, immunomagnetic beads assays detecting circulating anodic antigen (CAA) and circulating soluble egg antigen (CSEA), respectively, were investigated. By increasing the sample volume to 1.0 ml, the lower detection limit of antigen dilution series was improved six eight-fold in both immunomagnetic beads assays. Indeed, an improvement could be shown when testing the urine of Schistosoma-infected individuals with these magnetic beads assays. To compare the sensitivity of the immunomagnetic beads method with the standard ELISA, urine was experimentally adjusted to mirror low natural infection intensities. CSEA-positive urine samples were adjusted to levels below the detection limit of the corresponding ELISA and indeed were still found positive by the CSEA immunomagnetic beads assay. These results demonstrate that by using immunomagnetic beads, an assay method which can utilise larger sample volumes than an ELISA, enhanced detection can be achieved. This might be particularly valuable in areas with low prevalence of schistosomiasis or for the assessment of cure after chemotherapy.
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Affiliation(s)
- H A Nibbeling
- Laboratory of Parasitology, University of Leiden, The Netherlands
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De Bont J, Van Lieshout L, Deelder AM, Ysebaert MT, Vercruysse J. Circulating antigen levels in serum of cattle naturally infected with Schistosoma mattheei. Parasitology 1996; 113 ( Pt 5):465-71. [PMID: 8893532 DOI: 10.1017/s0031182000081531] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Levels of 2 Schistosoma circulating antigens, the circulating anodic antigen (CAA) and the circulating cathodic antigen (CCA), were determined in serum samples collected, on a monthly basis over a period of 1.5 years, from 32 farm animals of different ages and from 12 tracer calves exposed to Schistosoma mattheei infection on a Zambian farm. Faecal egg counts were monitored in all animals and worm burdens in tracers determined after perfusion. Antigen determination tests in serum, with sensitivities between 95 and 100% in heifers and adult cows, proved to be excellent tools for the diagnosis of cattle schistosomiasis. Also in young calves, some infections could be demonstrated earlier by CCA determination than by faecal egg examination. A poor correlation was seen between the data for faecal egg counts and for CAA and CCA levels. It therefore appears that circulating antigen measurements in serum are of limited value as indicators of the pathogenesis of infection in cattle. Although all tracer calves were found infected at perfusion, large variations were recorded in antigen levels. An unexpected finding was the observation in farm animals of a clear seasonal pattern in CAA levels, with significant increase between August and October during the second half of the dry season, when animals are subjected to heavy physical and nutritional stress. It therefore appears that, although circulating antigen determination may provide an indication of the worm burden in ageing infections, possible variations of antigen clearance rate with the physiological condition of the host may complicate the interpretation of the results.
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Affiliation(s)
- J De Bont
- Department of Clinical Studies, Samora Machel School of Veterinary Medicine, University of Zambia, Lusaka
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24
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Ramírez RM, Ceballos E, Alarcón de Noya B, Noya O, Bianco N. The immunopathology of human Schistosomiasis-III. Immunoglobulin isotype profiles and response to praziquantel. Mem Inst Oswaldo Cruz 1996; 91:593-9. [PMID: 9137744 DOI: 10.1590/s0074-02761996000500010] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/10/2023] Open
Abstract
Immunoglobulin (Ig) isotype (IgG, IgG1, IgG2, IgG3, IgG4, IgM, IgD and IgE) levels were investigated, both pre- and post-treatment with praziquantel (PZQ), in 43 adults and children chronically infected with Schistosoma mansoni, by means of a two-site, isotype-specific immunoenzymometric assay. The patients were classified as responders (R) or non-responders (NR) on the basis of their circumoval precipitin test (COPT) results 12 months after treatment. In comparison with controls, pre-treatment R children showed significantly higher levels of IgG, IgG1, IgG4 (p < 0.001) and IgE (p < 0.01); and diminished IgG2 (p < 0.05), while NR children showed significantly elevated levels only of IgE (p < 0.05). Twelve months after therapy, R children maintained significantly lower levels of IgG2, but showed significantly decreased levels of IgG, IgG1, IgG4, and IgE, while the Ig isotype profile of NR children was unaltered. Adult R and NR showed similar isotype profiles before chemotherapy, with the exception of significantly elevated IgM levels in R. Twelve months after therapy, R adults showed significantly decreased levels of IgG, IgG1, and IgG4, while NR adults showed only diminished IgG4 levels. These results reveal different Ig isotype profiles in untreated adults and children chronically infected with S. mansoni. The results further show that the pre-treatment Ig isotype profile may be significantly modified after an effective R to chemotherapy, accounted for by down regulation of the IgG1 isotype in association with negative seroconversion of the COPT in R patients. The COPT reaction has been associated with the highly specific egg glycoprotein antigen omega 1, which shows a significant reduction in reactivity six months after treatment. IgG1 may thus play a main role in the response against the omega 1 antigen.
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Affiliation(s)
- R M Ramírez
- Instituto de Inmunología, Facultad de Medicina, Universidad Central de Venezuela, Caracas, Venezuela
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25
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Bogers JJ, Nibbeling HA, Deelder AM, van Marck EA. Immunohistochemical and ultrastructural localization of Schistosoma mansoni soluble egg antigens processed by the infected host. Parasitology 1996; 112 ( Pt 6):537-43. [PMID: 8684828 DOI: 10.1017/s0031182000066117] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The detection of egg-derived antigens in the serum and urine of Schistosoma mansoni-infected individuals and experimental animals would provide an alternative method to assess the tissue egg burden. The detected levels are, however, not only a function of the amounts of antigen produced, but also of the processing or clearance by the host. In the present study the immunolocalization pattern of antigens using 2 recently described monoclonal antibodies to repetitive carbohydrate epitopes of S. mansoni soluble egg antigen (114-5B1-A and 114-4D12-A) in various organs of the host was investigated. In the liver strong immunoreactivity could be detected around the entrapped eggs and in egg-shells, as well as in Kupffer cells accumulating both antigen and schistosomal pigment. In the spleen, immunohistochemistry revealed antigen in the plasma as well as in secondary lysosomes of macrophages. Strong labelling was found in the vesicles of the eosinophilic granulocytes: indirect evidence perhaps for the presence of antigen-antibody complexes. In conclusion, the secreted egg antigens were sequestered in the reticulo-endothelial macrophages of the liver and the spleen as already partly described for worm-derived antigens. The presence of large quantities of antigenic material in the spleen could suggest an important role of this organ in the clearance of antigen and might even provide an additional explanation for the hepatosplenomegaly mainly present in S. mansoni-infected children.
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Affiliation(s)
- J J Bogers
- Laboratory of Pathology, University of Antwerp (UIA), Wilrijk, Belgium
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26
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Noya O, Fermín Z, Alarcón de Noya B, Losada S, Colmenares C, Hermoso T. Humoral immune response of children with chronic schistosomiasis. Isotype recognition of adult worm antigens. Parasite Immunol 1995; 17:319-28. [PMID: 7494645 DOI: 10.1111/j.1365-3024.1995.tb00898.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
In areas of low transmission of schistosomiasis, the evaluation of the success of control depends on reliable diagnostic tests. Under such conditions, some of the serological tests better estimate the real prevalence of this parasitosis than the classical stool examinations. On the search of highly sensitive and specific antigenic fractions for use in serological tests, an immunoblot technique with a luminescent substrate was used in order to evaluate, under dissociating and reducing conditions, the Schistosoma mansoni adult worm antigen (AWA). The sera of 30 infected Venezuelan children were assayed for specific recognition of AWA by IgG, IgM, IgE, IgA, and the four IgG subclasses. Eight highly specific polypeptide molecules from the parasite of 118, 114, 105, 74, 71, 45, 36, and 30 kDa were recognized by total IgG. Additionally, IgG1 and IgG2 recognized a molecule of 100 kDa and IgM one of 77 kDa. The present data suggests that certain molecules from the adult worm, specially the 36 kDa, might be relevant in the specific immunodiagnosis of this parasitic disease. The fact that the children antibodies were able to recognize the primary structure of these antigens, will allow us to chemically synthesize the relevant linear epitopes.
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Affiliation(s)
- O Noya
- Instituto de Medicina Tropical, Universidad Central de Venezuela
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Van Lieshout L, Panday UG, De Jonge N, Krijger FW, Oostburg BF, Polderman AM, Deelder AM. Immunodiagnosis of schistosomiasis mansoni in a low endemic area in Surinam by determination of the circulating antigens CAA and CCA. Acta Trop 1995; 59:19-29. [PMID: 7785523 DOI: 10.1016/0001-706x(94)00084-e] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
We evaluated the applicability of circulating antigen detection in serum and urine for the diagnosis of Schistosoma infections in a low endemic area. In total 389 individuals from Saramacca (Surinam) participated in the survey. Stool samples were examined using the Kato method, while circulating anodic antigen (CAA) and circulating cathodic antigen (CCA) were determined by highly specific monoclonal antibody-based ELISA's. Also schistosome specific IgM antibodies were measured by the indirect immunofluorescence assay, but the diagnostic performance of this test was found to be poor in this population. S. mansoni eggs were found in 29% of the examined cases, while CAA and CCA could be demonstrated in 23% and 17% of the serum samples and in 3% and 28% of the urine samples, respectively. Forty three percent of the study population was positive in at least one of these diagnostic assays, indicating that each individual test misses a substantial part of the subjects with an active infection. In most positive cases, intensities of infection were very low. As 204 individuals participated in all screening assays, diagnostic performance of each test was evaluated in this sub-population. The highest sensitivities were achieved with the urine-CCA assay and the parasitological examination, detecting 59 and 58 out of the 107 cases with an active infection, respectively. The serum-CAA assay detected 47 positive cases. Our results demonstrate that determination of circulating antigens, especially CCA in urine and CAA in serum, provides information additional to the parasitological examination, for the assessment of prevalence and intensity of Schistosoma infection in low endemic areas.
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Affiliation(s)
- L Van Lieshout
- Laboratory of Parasitology, University of Leiden, Netherlands
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28
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Bergwerff AA, van Dam GJ, Rotmans JP, Deelder AM, Kamerling JP, Vliegenthart JF. The immunologically reactive part of immunopurified circulating anodic antigen from Schistosoma mansoni is a threonine-linked polysaccharide consisting of –> 6)-(beta-D-GlcpA-(1 –> 3))-beta-D-GalpNAc-(1 –> repeating units. J Biol Chem 1994; 269:31510-7. [DOI: 10.1016/s0021-9258(18)31724-1] [Citation(s) in RCA: 56] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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29
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Van Dam GJ, Bergwerff AA, Thomas-Oates JE, Rotmans JP, Kamerling JP, Vliegenthart JF, Deelder AM. The immunologically reactive O-linked polysaccharide chains derived from circulating cathodic antigen isolated from the human blood fluke Schistosoma mansoni have Lewis x as repeating unit. Eur J Biochem 1994; 225:467-82. [PMID: 7925469 DOI: 10.1111/j.1432-1033.1994.00467.x] [Citation(s) in RCA: 98] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The gut-associated excretory antigen circulating cathodic antigen (CCA) was isolated by immunoaffinity chromatography from adult Schistosoma mansoni worms, which were collected from infected golden hamsters. This antigen is probably involved in protection of the schistosome gut and is increasingly used in highly sensitive and specific immunodiagnostic assays. Amino acid analysis before and after alkaline borohydride treatment of CCA and monosaccharide analysis indicated that CCA is O-glycosylated mostly via GalNAc-Thr. After reductive alkaline treatment, the O-linked carbohydrate chains were fractionated by gel-permeation chromatography, followed by normal-phase HPLC on LiChrosorb-NH2. Carbohydrate-positive fractions were investigated by one-dimensional and two-dimensional 1H-NMR spectroscopy, fast atom bombardment mass spectrometry and collision-induced-dissociation tandem mass spectrometry. The analyses showed that the low-molecular-mass O-linked oligosaccharide alditols (the minor fraction) consist of disaccharides to hexasaccharides having the Gal beta (1-3)GalNAc-OL core in common. The major carbohydrate fraction comprises a population of polysaccharides, containing Lewis x repeating units (-3)Gal beta (1-4)[Fuc alpha (1-3)]GlcNAc beta (1-). CCA-specific monoclonal antibodies and IgM antibodies in patient sera recognized the fucosylated O-linked carbohydrate antigenic structures. Since CCA evokes a strong IgM antibody response and carbohydrate structures containing repeating Lewis x units are found on circulating neutrophils, it is proposed that the antigenic poly-Lewis x polysaccharide of CCA is involved in the induction of auto-immunity against granulocytes, resulting in the mild to moderate neutropenia observed during schistosome infection.
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Affiliation(s)
- G J Van Dam
- Department of Parasitology, Faculty of Medicine, University of Leiden, The Netherlands
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30
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Abstract
An enzyme-linked immunosorbent assay was developed for combined measurement of schistosome circulating anodic antigen (CAA) and circulating cathodic antigen (CCA). Monoclonal antibodies against CAA and CCA were used as coating and as fluorescein-labeled detecting antibodies in a FITC-anti-FITC system. The lower detection limit of the assay was 1.1 ng antigen (AWA-TCA)/ml. Serum samples of Schistosoma mansoni infected individuals from Zaire (n = 60) and Burundi (n = 60) were tested in this assay and in single-antigen ELISAs. Sensitivities of assaying for CAA, CCA, combined CAA + CCA, and of parallel testing for CAA and for CCA were calculated from titres and antigen concentrations. With serum samples from the heavily infected individuals (Zaire), all assays had a sensitivity of 97% or higher. In contrast, with serum samples from individuals from Burundi (low to moderate infections) it was shown that combined testing resulted in a slightly lower sensitivity than testing for individual antigens. By parallel testing for CAA and CCA, the sensitivity could be increased considerably (to 95%), however.
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Affiliation(s)
- Y E Fillié
- Laboratory for Parasitology, Medical Faculty, University of Leiden, The Netherlands
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31
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Costa-Cruz JM, Hoshino-Shimizu S, Ferreira AW, Camargo ME, de Brito T, da Silva LC. Schistosoma mansoni circulating polysaccharide and protein antigens recognized by sheep antisera in patients with different clinical forms of schistosomiasis before and after treatment. Rev Inst Med Trop Sao Paulo 1994; 36:321-5. [PMID: 7732262 DOI: 10.1590/s0036-46651994000400004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Two sheep antisera, one of which raised against polysaccharide (Po) and other against protein (Pt) components of Schistosoma mansoni adult worms, were assessed by ELISA for their ability to detect circulating parasite antigens in patients with different clinical forms of chronic schistosomiasis mansoni. The former antiserum detected parasite antigens in liver granulomata and the latter in renal glomeruli from schistosomiasis patients and mice experimentally infected with S. mansoni. In general, the levels and/or positivity rate of circulating antigens and specific IgG antibodies were significantly higher in patients with hepatointestinal (HI) and hepatosplenic (HS) forms than in mild intestinal (I) forms. An association between Po antigens and clinical features of the disease was observed, as the level of these antigens was low (137 ng/ml) as well as the positivity rate (7.9%) in patients with I forms; values that were intermediate (593 ng/ml and 33.3%) in those with HI forms, and high (1.563 ng/ml and 50.0%) in more severe HS forms. The Pt antigens were detected in the studied clinical forms not differing statistically but, the positivity rate was significantly higher in HS forms comparatively to I forms. The antisera studied revealed distinct circulating antigen profiles, and the prognostic value of Po and Pt antigens was suggested.
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Affiliation(s)
- J M Costa-Cruz
- Departamento de Patologia, Universidade Federal de Uberlândia/MG, Brasil
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32
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Krijger FW, van Lieshout L, Deelder AM. A simple technique to pretreat urine and serum samples for quantitation of schistosome circulating anodic and cathodic antigen. Acta Trop 1994; 56:55-63. [PMID: 8203296 DOI: 10.1016/0001-706x(94)90040-x] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
For the detection of the circulating schistosome antigens CAA (circulating anodic antigen) and CCA (circulating cathodic antigen) in serum and urine samples of Schistosoma infected individuals, pretreatment of samples with trichloroacetic acid (TCA) is a standard procedure. In the present study several methods were evaluated in order to develop a more simple and rapid technique than the--especially for pretreatment of urine samples--laborious TCA technique. Optimal results were obtained with a method in which serum or urine samples were pretreated by a heat-incubation step (70 degrees C, 30 min) in an alkaline buffer (pH 9.6). In a comparison of the new technique with the TCA pretreatment, serum and urine samples of S. mansoni infected individuals from Zaire (n = 80) and of uninfected controls from The Netherlands (n = 208) were pretreated and assayed for CAA and CCA. Both pretreatment techniques showed similar sensitivities and specificities for CAA and CCA in serum, and CCA in urine. However, for the determination of CAA in urine the new technique performed significantly better, resulting in an increase of the sensitivity from 32 to 70% (titre determination).
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Affiliation(s)
- F W Krijger
- Laboratory of Parasitology, Medical Faculty, University of Leiden, The Netherlands
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33
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Da Silva AJ, Piuvezam MR, de Moura H, Maddison S, Peralta JM. Rapid competitive enzyme-linked immunosorbent assay using a monoclonal antibody reacting with a 15-kilodalton tegumental antigen of Schistosoma mansoni for serodiagnosis of schistosomiasis. J Clin Microbiol 1993; 31:2315-9. [PMID: 8408548 PMCID: PMC265753 DOI: 10.1128/jcm.31.9.2315-2319.1993] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
A competitive enzyme-linked immunosorbent assay (CELISA) for antibody detection was developed by using a monoclonal antibody which reacts with a 15-kDa tegumental antigen of the adult worm of Schistosoma mansoni. This monoclonal antibody was not able to react with antigens of Schistosoma japonicum or Schistosoma haematobium in enzyme-linked immunoelectrotransfer blot (EITB) and indirect immunofluorescence tests. The assay was performed in a period of 1 h using an adult worm crude extract antigen. To evaluate the CELISA, a total of 73 serum samples was analyzed: 35 were from S. mansoni-infected patients, 23 were from individuals with parasitic infections other than schistosomiasis, and 14 were from healthy individuals. All serum samples from healthy individuals and from patients infected with other parasites were negative, as were two (6%) samples from patients infected with S. mansoni. EITB analysis showed that 32 of 33 CELISA-positive samples were positive in the EITB but with different patterns of reactivity. A 15-kDa protein reacted with 60% of serum samples, and a 60-kDa protein showed the highest level of reactivity (85%). The two samples from patients infected with S. mansoni that were negative in the CELISA reacted with 70-, 60-, 50-, 47-, and 38-kDa proteins. One sample, positive in CELISA, did not react with proteins of the antigenic extract.
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Affiliation(s)
- A J Da Silva
- Centers for Disease Control, Atlanta, Georgia 30341-3724
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Kremsner PG, de Jonge N, Simarro PP, Mühlschlegel F, Mir M, Sima FO, Feldmeier H, Bienzle U, Deelder AM. Quantitative determination of circulating anodic and cathodic antigens in serum and urine of individuals infected with Schistosoma intercalatum. Trans R Soc Trop Med Hyg 1993; 87:167-9. [PMID: 8337718 DOI: 10.1016/0035-9203(93)90474-5] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Circulating anodic and cathodic Schistosoma antigens (CAA and CCA) have been determined by enzyme immunoassays in serum and urine of 60 individuals infected with S. intercalatum in Equatorial Guinea. The median egg output was 29 eggs/g of faeces (range 3-840). The egg output strongly correlated with concentrations of serum CAA (p = 0.47) and urine CAA (p = 0.42) (P < 0.001 for both); the later 2 quantities were also correlated with each other (p = 0.44, P < 0.001). All except 3 infected individuals had detectable amounts of serum CAA and/or urine CCA, a sensitivity of 95% for these 2 tests combined. Urine CAA was detected in 43% of patients. Serum CCA was detected in all infected individuals; however, no significant correlation was obtained between serum CCA levels and egg output in the stools of individual patients. This is the first study to demonstrate CCA in specimens of patients infected with S. intercalatum. The detection of CCA in urine is a new, non-invasive diagnostic method for S. intercalatum infection.
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Affiliation(s)
- P G Kremsner
- Landesinstitut für Tropenmedizin, Berlin, Federal Republic of Germany
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