1
|
Kartal L, Mueller I, Longley RJ. Using Serological Markers for the Surveillance of Plasmodium vivax Malaria: A Scoping Review. Pathogens 2023; 12:791. [PMID: 37375481 DOI: 10.3390/pathogens12060791] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2023] [Revised: 05/29/2023] [Accepted: 05/29/2023] [Indexed: 06/29/2023] Open
Abstract
The utilisation of serological surveillance methods for malaria has the potential to identify individuals exposed to Plasmodium vivax, including asymptomatic carriers. However, the application of serosurveillance varies globally, including variations in methodology and transmission context. No systematic review exists describing the advantages and disadvantages of utilising serosurveillance in various settings. Collation and comparison of these results is a necessary first step to standardise and validate the use of serology for the surveillance of P. vivax in specific transmission contexts. A scoping review was performed of P. vivax serosurveillance applications globally. Ninety-four studies were found that met predefined inclusion and exclusion criteria. These studies were examined to determine the advantages and disadvantages of serosurveillance experienced in each study. If studies reported seroprevalence results, this information was also captured. Measurement of antibodies serves as a proxy by which individuals exposed to P. vivax may be indirectly identified, including those with asymptomatic infections, which may be missed by other technologies. Other thematic advantages identified included the ease and simplicity of serological assays compared to both microscopy and molecular diagnostics. Seroprevalence rates varied widely from 0-93%. Methodologies must be validated across various transmission contexts to ensure the applicability and comparability of results. Other thematic disadvantages identified included challenges with species cross-reactivity and determining changes in transmission patterns in both the short- and long-term. Serosurveillance requires further refinement to be fully realised as an actionable tool. Some work has begun in this area, but more is required.
Collapse
Affiliation(s)
- Lejla Kartal
- School of Population and Global Health, The University of Melbourne, Parkville 3010, Australia
- Population Health and Immunity, The Walter and Eliza Hall Institute of Medical Research, Parkville 3052, Australia
| | - Ivo Mueller
- Population Health and Immunity, The Walter and Eliza Hall Institute of Medical Research, Parkville 3052, Australia
- Department of Medical Biology, The University of Melbourne, Parkville 3010, Australia
| | - Rhea J Longley
- Population Health and Immunity, The Walter and Eliza Hall Institute of Medical Research, Parkville 3052, Australia
- Department of Medical Biology, The University of Melbourne, Parkville 3010, Australia
| |
Collapse
|
2
|
França ACB, Françoso KS, Marques RF, Trossini GHG, Gomes RA, Póvoa MM, Cunha MG, Silveira ELV, Soares IS. Antibodies Against the Plasmodium vivax Apical Membrane Antigen 1 From the Belem Strain Share Common Epitopes Among Other Worldwide Variants. Front Cell Infect Microbiol 2021; 11:616230. [PMID: 33796476 PMCID: PMC8009186 DOI: 10.3389/fcimb.2021.616230] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2020] [Accepted: 02/23/2021] [Indexed: 12/31/2022] Open
Abstract
Malaria is a human parasitic disease distributed in many tropical countries and caused by various Plasmodium species. Plasmodium vivax has the largest geographical distribution of the Plasmodium species and is predominant in the Americas, including Brazil. Only a small number of P. vivax vaccine formulations have successfully reached clinical trials relative to their P. falciparum counterparts. One of the candidate antigens for a blood-stage P. vivax vaccine is apical membrane antigen 1 (PvAMA-1). Due to the worldwide distribution of Plasmodium parasites, a high degree of variability has been detected in this antigen sequence, representing a considerable challenge to the development of a universal vaccine against malaria. In this study, we evaluated how PvAMA-1 polymorphisms influence vaccine-derived immune responses in P. vivax malaria. To this end, we expressed 9 recombinant protein representatives of different PvAMA-1 allelic variants in the yeast Pichia pastoris: Belem, Chesson I, Sal-1, Indonesia XIX, SK0814, TC103, PNG_05_ESP, PNG_62_MU, and PNG_68_MAS. After protein expression and purification, we evaluated the breadth of the immune responses derived from malaria-exposed individuals from the Amazon region. From 611 serum samples of malaria-exposed individuals, 53.68% of them reacted against the PvAMA-1 Belem through ELISA. Positive samples were further tested against recombinant proteins representing the other PvAMA-1 allelic variants. Whereas Sal-1, Chesson I and SK0814 variants were highly recognized by tested serum samples, Indonesia XIX, TC103, PNG_05_ESP, PNG_62_MU, and PNG_68_MAS were only slightly recognized. Moreover, polyclonal sera derived from C57BL/6 mice immunized with the PvAMA-1 Belem protein predominantly recognized Belem, Sal-1, Chesson I, SK0814, and Indonesia XIX through ELISA. Last, ELISA-based competition assays demonstrated that a previous interaction between anti-Belem polyclonal serum and Sal-1, Chesson I, SK0814, or Indonesia XIX proteins could further inhibit antibody binding to the Belem variant. Our human and mouse data suggest the presence of common epitopes or cross-reactivity between Belem, Sal-1, Chesson I, and SK0814 variants. Although the PvAMA-1 Belem variant induces strain-transcendent antibodies, PvAMA-1 variants from Thailand and Papua New Guinea may need to be included in a universal vaccine formulation to achieve protection against P. vivax malaria.
Collapse
Affiliation(s)
- Ana Caroline Barbosa França
- Department of Clinical and Toxicological Analyses, School of Pharmaceutical Sciences, University of São Paulo, São Paulo, Brazil
| | - Kátia Sanches Françoso
- Department of Clinical and Toxicological Analyses, School of Pharmaceutical Sciences, University of São Paulo, São Paulo, Brazil
| | - Rodolfo Ferreira Marques
- Department of Clinical and Toxicological Analyses, School of Pharmaceutical Sciences, University of São Paulo, São Paulo, Brazil
| | - Gustavo H. G. Trossini
- Department of Pharmacy, School of Pharmaceutical Sciences, University of São Paulo, São Paulo, Brazil
| | - Renan A. Gomes
- Department of Pharmacy, School of Pharmaceutical Sciences, University of São Paulo, São Paulo, Brazil
| | | | - Maristela G. Cunha
- Instituto de Ciências Biológicas, Universidade Federal do Pará, Belém, Brazil
| | - Eduardo L. V. Silveira
- Department of Clinical and Toxicological Analyses, School of Pharmaceutical Sciences, University of São Paulo, São Paulo, Brazil
| | - Irene S. Soares
- Department of Clinical and Toxicological Analyses, School of Pharmaceutical Sciences, University of São Paulo, São Paulo, Brazil
| |
Collapse
|
3
|
Analyses of the expression, immunohistochemical properties and serodiagnostic potential of Schistosoma japonicum peroxiredoxin-4. Parasit Vectors 2020; 13:436. [PMID: 32867818 PMCID: PMC7460784 DOI: 10.1186/s13071-020-04313-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Accepted: 08/24/2020] [Indexed: 12/31/2022] Open
Abstract
Background Schistosoma japonicum, which inhabits the mesenteric vein of the mammalian hosts for about 20 to 30 years, is subjected to the oxidative stresses from the host defense mechanism during their intra-mammalian stages. To counteract this host immune attack, the parasite utilizes their antioxidant system for survival inside the host. Peroxiredoxins (Prxs), thiol-specific antioxidant proteins, play an essential role for protecting the parasite against oxidative stress by reducing hydrogen peroxide to water. Only three types of 2-Cys Prxs have been previously characterized in S. japonicum whereas a fourth Prx has been identified for Schistosoma mansoni as Prx-4. A sequence coding homologous to this gene in the S. japonicum database was identified, characterized and expressed as recombinant SjPrx-4 protein (rSjPrx-4). Furthermore, rSjPrx-4 was evaluated in this study for its diagnostic potentials in detecting S. japonicum infection in humans. Results The gene found in the parasite genome contained 2 active-site cysteines with conserved sequences in the predicted amino acid (AA) sequence and showed 75% identity with that of the previously characterized Prx (TPx-1) of S. japonicum. The gene was expressed in different stages of schistosome life-cycle with highest transcription level in the adult male. The gene was cloned into a plasmid vector and then transfected into Escherichia coli for expression of rSjPrx-4. Anti-rSjPrx-4 mouse sera recognized native SjPrx-4 in egg and adult worm lysate by western blotting. The result of a mixed function oxidation assay in which rSjPrx-4 prevented the nicking of DNA from hydroxyl radicals confirmed its antioxidant activity. Subsequently, immunolocalization analysis showed the localization of SjPrx-4 inside the egg, on the tegument and in the parenchyma of the adult worm. Enzyme-linked immunosorbent assay results showed that rSjPrx-4 has 83.3% sensitivity and 87.8% specificity. Its diagnostic potential was further evaluated in combination with recombinant SjTPx-1 protein, yielding an improved sensitivity and specificity of 90% and 92.7%, respectively. Conclusions These results suggest that SjPrx-4 plays a role as an antioxidant dealing with oxidative stresses of S. japonicum, and its diagnostic potential improved by coupling it with SjTPx-1 is a proof for developing a serological test with better diagnostic performance for human schistosomiasis.![]()
Collapse
|
4
|
Moendeg KJ, Angeles JMM, Goto Y, Leonardo LR, Kirinoki M, Villacorte EA, Rivera PT, Inoue N, Chigusa Y, Kawazu SI. Development and optimization of cocktail-ELISA for a unified surveillance of zoonotic schistosomiasis in multiple host species. Parasitol Res 2015; 114:1225-8. [DOI: 10.1007/s00436-015-4312-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2014] [Accepted: 01/07/2015] [Indexed: 12/13/2022]
|
5
|
Cutts JC, Powell R, Agius PA, Beeson JG, Simpson JA, Fowkes FJI. Immunological markers of Plasmodium vivax exposure and immunity: a systematic review and meta-analysis. BMC Med 2014; 12:150. [PMID: 25199532 PMCID: PMC4172944 DOI: 10.1186/s12916-014-0150-1] [Citation(s) in RCA: 64] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/16/2014] [Accepted: 08/12/2014] [Indexed: 01/25/2023] Open
Abstract
BACKGROUND Identifying Plasmodium vivax antigen-specific antibodies associated with P. vivax infection and protective immunity is key to the development of serosurveillance tools and vaccines for malaria. Antibody targets of P. vivax can be identified by seroepidemiological studies of individuals living in P. vivax-endemic areas, and is an important strategy given the limited ability to culture P. vivax in vitro. There have been numerous studies investigating the association between P. vivax antibody responses and P. vivax infection, but there has been no standardization of results to enable comparisons across populations. METHODS We performed a systematic review with meta-analysis of population-based, cross-sectional, case-control, and cohort studies of individuals living in P. vivax-endemic areas. We searched 6 databases and identified 18 studies that met predefined inclusion and quality criteria, and examined the association between antibody responses to P. vivax antigens and P. vivax malaria. RESULTS The majority of studies were published in South America (all from Brazil) and the rest from geographically diverse areas in the Asia-Pacific region. Considerable heterogeneity in estimates was observed, but IgG responses to PvCSP, PvMSP-119, PvMSP-9RIRII, and PvAMA1 were associated with increased odds of P. vivax infection in geographically diverse populations. Potential sources of heterogeneity included study design, different transmission intensities and transmigrant populations. Protective associations were observed for antibodies to PvMSP-119, PvMSP-1NT, PvMSP-3α and PvMSP-9NT antigens, but only in single geographical locations. CONCLUSIONS This systematic review revealed several antigen-specific antibodies that were associated with active infection and protective immunity, which may be useful biomarkers. However, more studies are needed on additional antigens, particularly cohort studies to increase the body of evidence for protective immunity. More studies representing diverse geographical regions encompassing varying P. vivax endemicities are needed to validate the generalizability of the findings and to provide a solid evidence base for the use of P. vivax antigens in vaccines and serosurveillance tools.
Collapse
|
6
|
Nam HW, Song KJ, Ahn HJ, Yang Z, Chong CK, Cho PY, Ahn SK, Kim TS. Probability of antibody formation against circumsporozoite protein of Plasmodium vivax among Korean malaria patients. THE KOREAN JOURNAL OF PARASITOLOGY 2014; 52:143-9. [PMID: 24850957 PMCID: PMC4028451 DOI: 10.3347/kjp.2014.52.2.143] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/28/2013] [Accepted: 12/14/2013] [Indexed: 11/26/2022]
Abstract
To evaluate the seroprevalence against circumsporozoite protein (CSP) of Plasmodium vivax in sera of Korean patients, the central repeating domain (CRD) of CSP was cloned and analyzed. From the genomic DNA of patient's blood, 2 kinds of CSPs were identified to belong to a VK210 type, which is the dominant repeating of GDRA(D/A)GQPA, and named as PvCSPA and PvCSPB. Recombinantly expressed his-tagged PvCSPA or PvCSPB in Escherichia coli reacted well against sera of patients in western blot, with the detecting rate of 47.9% (58/121), which included 15 cases positive for PvCSPA, 6 cases positive for PvCSPB, and 37 cases for both. The mixture of PvCSPA and PvCSPB was loaded to a rapid diagnostic test kit (RDT) and applied with the same set of patient sera, which resulted in detection rates of 57.0% (69/121). When the protein sequences of PvCSPA were compared with those of P. vivax in endemic regions of India and Uganda, they were compatibly homologous to PvCSPA with minor mutations. These results suggested that the recombinant PvCSPA and PvCSPB loaded RDT may be a milestone in latent diagnosis which has been a hot issue of domestic malaria and important for radical therapy in overlapped infections with P. falciparum in tropical and subtropical areas. During the biological process of malarial infection, exposure of CSP to antigen-antibody reaction up to 57.0% is the first report in Korea.
Collapse
Affiliation(s)
- Ho-Woo Nam
- Department of Parasitology, College of Medicine, The Catholic University of Korea, Seoul 137-701, Korea
| | - Kyoung Ju Song
- Department of Parasitology, College of Medicine, The Catholic University of Korea, Seoul 137-701, Korea
| | - Hye Jin Ahn
- Department of Parasitology, College of Medicine, The Catholic University of Korea, Seoul 137-701, Korea
| | - Zhaoshou Yang
- Department of Parasitology, College of Medicine, The Catholic University of Korea, Seoul 137-701, Korea
| | | | - Pyo Yun Cho
- Department of Tropical Medicine and Parasitology, Inha University School of Medicine, Incheon 400-712, Korea
| | - Seong Kyu Ahn
- Department of Tropical Medicine and Parasitology, Inha University School of Medicine, Incheon 400-712, Korea
| | - Tong-Soo Kim
- Department of Tropical Medicine and Parasitology, Inha University School of Medicine, Incheon 400-712, Korea
| |
Collapse
|
7
|
Chen SB, Ju C, Chen JH, Zheng B, Huang F, Xiao N, Zhou X, Ernest T, Zhou XN. Operational research needs toward malaria elimination in China. ADVANCES IN PARASITOLOGY 2014; 86:109-33. [PMID: 25476883 DOI: 10.1016/b978-0-12-800869-0.00005-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Owing to the implementation of a national malaria elimination programme from 2010 to 2020, we performed a systematic review to assess research challenges in the People's Republic of China (P.R. China) and define research priorities in the next few years. A systematic search was conducted for articles published from January 2000 to December 2012 in international journals from PubMed and Chinese journals from the China National Knowledge Infrastructure (CNKI). In total, 2532 articles from CNKI and 308 articles from PubMed published between 2010 and 2012 related to malaria after unrelated references and review or comment were further excluded, and a set of research gaps have been identified that could hinder progress toward malaria elimination in P.R. China. For example, there is a lack of sensitive and specific tests for the diagnosis of malaria cases with low parasitemia, and there is a need for surveillance tools that can evaluate the epidemic status for guiding the elimination strategy. Hence, we argue that malaria elimination will be accelerated in P.R. China through the development of new tests, such as detection of parasite or drug resistance, monitoring glucose-6-phosphate dehydrogenase (G6PD) deficiency, active malaria screening methods, and understanding the effects of the environment and climate variation on vector distribution.
Collapse
Affiliation(s)
- Shen-Bo Chen
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention; Key Laboratory of Parasite and Vector Biology of the Chinese Ministry of Health; WHO Collaborating Centre for Malaria, Schistosomiasis and Filariasis, Shanghai, People's Republic of China
| | - Chuan Ju
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention; Key Laboratory of Parasite and Vector Biology of the Chinese Ministry of Health; WHO Collaborating Centre for Malaria, Schistosomiasis and Filariasis, Shanghai, People's Republic of China
| | - Jun-Hu Chen
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention; Key Laboratory of Parasite and Vector Biology of the Chinese Ministry of Health; WHO Collaborating Centre for Malaria, Schistosomiasis and Filariasis, Shanghai, People's Republic of China
| | - Bin Zheng
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention; Key Laboratory of Parasite and Vector Biology of the Chinese Ministry of Health; WHO Collaborating Centre for Malaria, Schistosomiasis and Filariasis, Shanghai, People's Republic of China
| | - Fang Huang
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention; Key Laboratory of Parasite and Vector Biology of the Chinese Ministry of Health; WHO Collaborating Centre for Malaria, Schistosomiasis and Filariasis, Shanghai, People's Republic of China
| | - Ning Xiao
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention; Key Laboratory of Parasite and Vector Biology of the Chinese Ministry of Health; WHO Collaborating Centre for Malaria, Schistosomiasis and Filariasis, Shanghai, People's Republic of China
| | - Xia Zhou
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention; Key Laboratory of Parasite and Vector Biology of the Chinese Ministry of Health; WHO Collaborating Centre for Malaria, Schistosomiasis and Filariasis, Shanghai, People's Republic of China
| | - Tambo Ernest
- Center for Sustainable Malaria Control, Faculty of Natural and Environmental Science; Center for Sustainable Malaria Control, Biochemistry Department, Faculty of Natural and Agricultural Sciences, University of Pretoria, Pretoria, South Africa
| | - Xiao-Nong Zhou
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention; Key Laboratory of Parasite and Vector Biology of the Chinese Ministry of Health; WHO Collaborating Centre for Malaria, Schistosomiasis and Filariasis, Shanghai, People's Republic of China
| |
Collapse
|
8
|
Parija SC, Gireesh A. Cysticercus cellulosae antigens in the serodiagnosis of neurocysticercosis. Trop Parasitol 2013; 1:64-72. [PMID: 23508242 PMCID: PMC3593475 DOI: 10.4103/2229-5070.86932] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2011] [Accepted: 10/31/2011] [Indexed: 11/04/2022] Open
Abstract
Neurocysticercosis (NCC) is difficult to diagnose clinically because of its varied clinical presentation. However, an accurate diagnosis is possible only after suspicion on epidemiological grounds, proper interpretation of the clinical data, analysis of the findings on imaging studies, and specific immunological tests on the serum and cerebrospinal fluid (CSF). The diagnosis of NCC by any single parameter thus continues to remain difficult. In the past, detection of NCC was based on autopsy studies and histological confirmation. In recent times, the advent of imaging methods such as computed tomography and magnetic resonance imaging have provided excellent non-invasive tools for easy detection of NCC. Nevertheless, an imaging technique of the brain, although useful, is not considered as a gold standard for the diagnosis of NCC. Serological tests are being increasingly used in adjunct with imaging techniques, to aid the diagnosis of NCC. Immunodiagnostic techniques include detection methods for specific antibodies and for circulating parasite antigens in the serum and CSF. Currently, many of the immunodiagnostic tests, including the enzyme-linked immunosorbent assay and enzyme immunotransfer blot, use purified native antigens for the immunodiagnosis of NCC. Nevertheless, the main problem with the use of native cysticercal antigens is that the native proteins often show cross reactions with sera from humans infected with other parasites. The preparation of native antigens also demand a constant supply of parasitic material from the intermediate host pig. In order to overcome the problems in using native antigens, the recombinant antigens or synthetic peptides, which can be produced under stable conditions, are being evaluated for the serodiagnosis of NCC.
Collapse
Affiliation(s)
- Subhash Chandra Parija
- Department of Microbiology, Jawaharlal Institute of Postgraduate Medical Education and Research (JIPMER), Puducherry, India
| | | |
Collapse
|
9
|
de Carvalho GB, de Carvalho GB. Duffy Blood Group System and the malaria adaptation process in humans. Rev Bras Hematol Hemoter 2013; 33:55-64. [PMID: 23284245 PMCID: PMC3521437 DOI: 10.5581/1516-8484.20110016] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2010] [Accepted: 02/04/2011] [Indexed: 11/27/2022] Open
Abstract
Malaria is an acute infectious disease caused by the protozoa of the genus
Plasmodium. The antigens of the Duffy Blood Group System, in addition to
incompatibilities in transfusions and hemolytic disease of the newborn, are of great
interest in medicine due to their association with the invasion of red blood cells by
the parasite Plasmodium vivax. For invasions to occur an interaction between the
parasites and antigens of the Duffy Blood Group System is necessary. In Caucasians
six antigens are produced by the Duffy locus (Fya, Fyb, F3, F4, F5 and F6). It has
been observed that Fy(a-b-) individuals are resistant to Plasmodium knowlesi and P.
vivax infection, because the invasion requires at least one of these antigens. The P.
vivax Duffy Binding Protein (PvDBP) is functionally important in the invasion process
of these parasites in Duffy / DARC positive humans. The proteins or fractions may be
considered, therefore, an important and potential inoculum to be used in immunization
against malaria.
Collapse
|
10
|
Haghi AM, Khoramizade MR, Nateghpour M, Mohebali M, Edrissian GH, Eshraghian MR, Sepehrizadeh Z. A recombinant Plasmodium vivax apical membrane antigen-1 to detect human infection in Iran. THE KOREAN JOURNAL OF PARASITOLOGY 2012; 50:15-21. [PMID: 22451729 PMCID: PMC3309046 DOI: 10.3347/kjp.2012.50.1.15] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/22/2011] [Revised: 12/20/2011] [Accepted: 01/07/2012] [Indexed: 11/23/2022]
Abstract
In Iran, Plasmodium vivax is responsible for more than 80% of the infected cases of malaria per year. Control interventions for vivax malaria in humans rely mainly on developed diagnostic methods. Recombinant P. vivax apical membrane antigen-1 (rPvAMA-1) has been reported to achieve designing rapid, sensitive, and specific molecular diagnosis. This study aimed to perform isolation and expression of a rPvAMA-1, derived from Iranian patients residing in an endemic area. Then, the diagnostic efficiency of the characterized Iranian PvAMA-1 was assessed using an indirect ELISA method. For this purpose, a partial region of AMA-1 gene was amplified, cloned, and expressed in pET32a plasmid. The recombinant His-tagged protein was purified and used to coat the ELISA plate. Antibody detection was assessed by indirect ELISA using rPvAMA-1. The validity of the ELISA method for detection of anti-P. vivax antibodies in the field was compared to light microscopy on 84 confirmed P. vivax patients and compared to 84 non-P. vivax infected individuals. The ELISA cut-off value was calculated as the mean+2SD of OD values of the people living in malaria endemic areas from a south part of Iran. We found a cut-off point of OD=0.311 that showed the best correlation between the sera confirmed with P. vivax infection and healthy control sera. A sensitivity of 81.0% and specificity of 84.5% were found at this cut off titer. A good degree of statistical agreement was found between ELISA using rPvAMA-1 and light microscopy (0.827) by Kappa analysis.
Collapse
Affiliation(s)
- Afsaneh Motevalli Haghi
- Department of Medical Parasitology and Mycology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | | | | | | | | | | | | |
Collapse
|
11
|
Abstract
Many of malaria's signs and symptoms are indistinguishable from those of other febrile diseases. Detection of the presence of Plasmodium parasites is essential, therefore, to guide case management. Improved diagnostic tools are required to enable targeted treatment of infected individuals. In addition, field-ready diagnostic tools for mass screening and surveillance that can detect asymptomatic infections of very low parasite densities are needed to monitor transmission reduction and ensure elimination. Antibody-based tests for infection and novel methods based on biomarkers need further development and validation, as do methods for the detection and treatment of Plasmodium vivax. Current rapid diagnostic tests targeting P. vivax are generally less effective than those targeting Plasmodium falciparum. Moreover, because current drugs for radical cure may cause serious side effects in patients with glucose-6-phosphate dehydrogenase (G6PD) deficiency, more information is needed on the distribution of G6PD-deficiency variants as well as tests to identify at-risk individuals. Finally, in an environment of very low or absent malaria transmission, sustaining interest in elimination and maintaining resources will become increasingly important. Thus, research is required into the context in which malaria diagnostic tests are used, into diagnostics for other febrile diseases, and into the integration of these tests into health systems.
Collapse
|
12
|
Detection of Plasmodium falciparum, P. vivax, P. ovale, and P. malariae merozoite surface protein 1-p19 antibodies in human malaria patients and experimentally infected nonhuman primates. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2010; 17:1631-8. [PMID: 20702658 DOI: 10.1128/cvi.00196-10] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Approximately 3.2 billion people live in areas where malaria is endemic, and WHO estimates that 350 to 500 million malaria cases occur each year worldwide. This high prevalence, and the high frequency of international travel, creates significant risk for the exportation of malaria to countries where malaria is not endemic and for the introduction of malaria organisms into the blood supply. Since all four human infectious Plasmodium species have been transmitted by blood transfusion, we sought to develop an enzyme-linked immunosorbent assay (ELISA) capable of detecting antibodies elicited by infection with any of these species. The merozoite surface protein 1 (MSP1), a P. falciparum and P. vivax vaccine candidate with a well-characterized immune response, was selected for use in the assay. The MSP1 genes from P. ovale and P. malariae were cloned and sequenced (L. Birkenmeyer, A. S. Muerhoff, G. Dawson, and S. M. Desai, Am. J. Trop. Med. Hyg. 82:996-1003, 2010), and the carboxyl-terminal p19 regions of all four species were expressed in Escherichia coli. Performance results from individual p19 ELISAs were compared to those of a commercial test (Lab 21 Healthcare Malaria enzyme immunoassay [EIA]). The commercial ELISA detected all malaria patients with P. falciparum or P. vivax infections, as did the corresponding species-specific p19 ELISAs. However, the commercial ELISA detected antibodies in 0/2 and 5/8 individuals with P. malariae and P. ovale infections, respectively, while the p19 assays detected 100% of individuals with confirmed P. malariae or P. ovale infections. In experimentally infected nonhuman primates, the use of MSP1-p19 antigens from all four species resulted in the detection of antibodies within 2 to 10 weeks postinfection. Use of MSP1-p19 antigens from all four Plasmodium species in a single immunoassay would provide significantly improved efficacy compared to existing tests.
Collapse
|
13
|
Birkenmeyer L, Muerhoff AS, Dawson GJ, Desai SM. Isolation and characterization of the MSP1 genes from Plasmodium malariae and Plasmodium ovale. Am J Trop Med Hyg 2010; 82:996-1003. [PMID: 20519591 DOI: 10.4269/ajtmh.2010.09-0022] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
The merozoite surface protein 1 (MSP1) is the principal surface antigen of the blood stage form of the Plasmodium parasite. Antibodies recognizing MSP1 are frequently detected following Plasmodium infection, making this protein a significant component of malaria vaccines and diagnostic tests. Although the MSP1 gene sequence has been reported for Plasmodium falciparum and Plasmodium vivax, this gene has not been identified for the other two major human-infectious species, Plasmodium malariae and Plasmodium ovale. MSP1 genes from these two species were isolated from Cameroon blood donor samples. The genes are similar in size to known MSP1 genes and encode proteins with interspecies conserved domains homologous to those identified in other Plasmodium species. Sequence and phylogenetic analysis of all available Plasmodium MSP1 amino acid sequences clearly shows that the Po and Pm MSP1 sequences are truly unique within the Plasmodium genus and not simply Pf or Pv variants.
Collapse
Affiliation(s)
- Larry Birkenmeyer
- Abbott Diagnostics, Infectious Diseases R&D, Dept. 09NB, Bldg. AP20, 100 Abbott Park Road, Abbott Park, IL 60064-6015, USA.
| | | | | | | |
Collapse
|
14
|
A new ELISA kit which uses a combination of Plasmodium falciparum extract and recombinant Plasmodium vivax antigens as an alternative to IFAT for detection of malaria antibodies. Malar J 2007; 6:19. [PMID: 17313669 PMCID: PMC1819385 DOI: 10.1186/1475-2875-6-19] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2006] [Accepted: 02/21/2007] [Indexed: 11/30/2022] Open
Abstract
Background The methods most commonly used to measure malarial antibody titres are the Indirect Fluorescence Antibody Test (IFAT), regarded as the gold standard, and the Enzyme-Linked ImmunoSorbent Assay (ELISA). The objective here was to assess the diagnostic performance, i.e. the sensitivity and specificity, of a new malaria antibody ELISA kit in comparison to IFAT. This new ELISA kit, the ELISA malaria antibody test (DiaMed), uses a combination of crude soluble Plasmodium falciparum extract and recombinant Plasmodium vivax antigens. Methods Two groups were used: 95 samples from malaria patients to assess the clinical sensitivity and 2,152 samples from blood donors, who had not been exposed to malaria, to assess the clinical specificity. Results The DiaMed ELISA test kit had a clinical sensitivity of 84.2% and a clinical specificity of 99.6% as compared with 70.5% and 99.6% respectively, using the IFAT method. The ELISA method was more sensitive than the IFAT method for P. vivax infections (75% vs. 25%). However, in 923 malaria risk donors the analytical sensitivity of the ELISA test was 40% and its specificity 98.3%, performances impaired by large numbers of equivocal results non-concordant between ELISA and IFAT. When the overall analytical performances of ELISA was compared to IFAT, the ELISA efficiency J index was 0.84 versus 0.71 for IFAT. Overall analytical sensitivity was 93.1% and the analytical specificity 96.7%. Overall agreement between the two methods reached 0.97 with a reliability k index of 0.64. Conclusion The DiaMed ELISA test kit shows a good correlation with IFAT for analytical and clinical parameters. It may be an interesting method to replace the IFAT especially in blood banks, but further extensive investigations are needed to examine the analytical performance of the assay, especially in a blood bank setting.
Collapse
|