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Pastor AF, Silva MR, Dos Santos WJT, Rego T, Brandão E, de-Melo-Neto OP, Rocha A. Recombinant antigens used as diagnostic tools for lymphatic filariasis. Parasit Vectors 2021; 14:474. [PMID: 34526120 PMCID: PMC8442287 DOI: 10.1186/s13071-021-04980-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Accepted: 08/26/2021] [Indexed: 11/13/2022] Open
Abstract
Lymphatic filariasis (LF) is a parasitic disease caused by the worms Wuchereria bancrofti, Brugia malayi, or Brugia timori. It is a tropical and subtropical illness that affects approximately 67 million people worldwide and that still requires better diagnostic tools to prevent its spread and enhance the effectiveness of control procedures. Traditional parasitological tests and diagnostic methods based on whole protein extracts from different worms are known for problems related to sample time collection, sensitivity, and specificity. More recently, new diagnostic tools based on immunological methods using recombinant antigens have been developed. The current review describes the several recombinant antigens used as tools for lymphatic filariasis diagnosis in antigen and antibody capture assays, highlighting their advantages and limitations as well as the main commercial tests developed based on them. The literature chronology is from 1991 to 2021. First, it describes the historical background related to the identification of relevant antigens and the generation of the recombinant polypeptides used for the LF diagnosis, also detailing features specific to each antigen. The subsequent section then discusses the use of those proteins to develop antigen and antibody capture tests to detect LF. So far, studies focusing on antibody capture assays are based on 13 different antigens with at least six commercially available tests, with five proteins further used for the development of antigen capture tests. Five antigens explored in this paper belong to the SXP/RAL-2 family (BmSXP, Bm14, WbSXP-1, Wb14, WbL), and the others are BmShp-1, Bm33, BmR1, BmVAH, WbVAH, BmALT-1, BmALT-2, and Wb123. It is expected that advances in research with these antigens will allow further development of tests combining both sensitivity and specificity with low costs, assisting the Global Program to Eliminate Lymphatic Filariasis (GPELF). ![]()
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Affiliation(s)
- André Filipe Pastor
- Fundação Oswaldo Cruz-Fiocruz, Instituto Aggeu Magalhães, Recife, PE, Brazil. .,Instituto Federal de Educação, Ciência e Tecnologia do Sertão Pernambucano (IFSertao-PE), Campus Floresta, Floresta, PE, Brazil.
| | | | | | - Tamisa Rego
- Fundação Oswaldo Cruz-Fiocruz, Instituto Aggeu Magalhães, Recife, PE, Brazil
| | - Eduardo Brandão
- Fundação Oswaldo Cruz-Fiocruz, Instituto Aggeu Magalhães, Recife, PE, Brazil.,Fundação Oswaldo Cruz-Fiocruz, Instituto Aggeu Magalhães, Serviço de Referência Nacional em Filarioses, Recife, PE, Brazil
| | | | - Abraham Rocha
- Fundação Oswaldo Cruz-Fiocruz, Instituto Aggeu Magalhães, Recife, PE, Brazil.,Fundação Oswaldo Cruz-Fiocruz, Instituto Aggeu Magalhães, Serviço de Referência Nacional em Filarioses, Recife, PE, Brazil.,Laboratório do Hospital Otávio de Freitas, Secretaria de Saúde do Estado de Pernambuco, Recife, PE, Brazil
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Rahumatullah A, Lim TS, Yunus MH, Noordin R. Development of an Antigen Detection ELISA for Bancroftian Filariasis Using BmSXP-Specific Recombinant Monoclonal Antibody. Am J Trop Med Hyg 2020; 101:436-440. [PMID: 31162018 DOI: 10.4269/ajtmh.19-0034] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Lymphatic filariasis is a mosquito-borne parasitic disease responsible for morbidity and disability that affects 1.2 billion people worldwide, mainly the poor communities. Currently, filarial antigen testing is the method of choice for the detection of bancroftian filariasis, and to date, there are two commonly used tests. In the present study, a recently reported recombinant monoclonal antibody (5B) specific to BmSXP filarial antigen was used in developing an ELISA for the detection of circulating filarial antigen in sera of patients with bancroftian filariasis. The performance of the ELISA was evaluated using 124 serum samples. The ELISA was positive with all sera from microfilaremic bancroftian filariasis patients (n = 34). It also showed 100% diagnostic specificity when tested with sera from 50 healthy individuals and 40 patients with other parasitic diseases. The developed assay using the novel 5B recombinant monoclonal antibody could potentially be a promising alternative antigen detection test for bancroftian filariasis.
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Affiliation(s)
- Anizah Rahumatullah
- Institute for Research in Molecular Medicine (INFORMM), Universiti Sains Malaysia, Pulau Pinang, Malaysia
| | - Theam Soon Lim
- Institute for Research in Molecular Medicine (INFORMM), Universiti Sains Malaysia, Pulau Pinang, Malaysia
| | - Muhammad Hafiznur Yunus
- Institute for Research in Molecular Medicine (INFORMM), Universiti Sains Malaysia, Pulau Pinang, Malaysia
| | - Rahmah Noordin
- Institute for Research in Molecular Medicine (INFORMM), Universiti Sains Malaysia, Pulau Pinang, Malaysia
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Noordin R, Mohd Zain SN, Yunus MH, Sahimin N. Seroprevalence of lymphatic filariasis among migrant workers in Peninsular Malaysia. Trans R Soc Trop Med Hyg 2018; 111:370-372. [PMID: 29206992 DOI: 10.1093/trstmh/trx062] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2017] [Accepted: 11/06/2017] [Indexed: 11/13/2022] Open
Abstract
Background Malaysia aims to eliminate lymphatic filariasis (LF) by the year 2020, thus the potential threat of LF from migrant workers needs to be investigated. Methods Brugian and bancroftian filariasis among 484 migrant workers from six countries were investigated using rapid tests based on detection of specific IgG4 antibodies against BmR1 (Brugia Rapid) and BmSXP recombinant antigens. Results The seroprevalence of brugian filariasis was very low; however, bancroftian filariasis was notable among workers from India, Nepal and Myanmar. Conclusion Malaysia is not endemic for Wuchereria bancrofti, but harbors the vectors for the parasite, thus the results showed that migrant workers should be monitored for this infection.
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Affiliation(s)
- Rahmah Noordin
- Institute for Research in Molecular Medicine (INFORMM), Universiti Sains Malaysia, 11800 Penang
| | - Siti Nursheena Mohd Zain
- Institute of Biological Science, Faculty of Science, University of Malaya, Kuala Lumpur, Malaysia
| | - Muhammad Hafiznur Yunus
- Institute for Research in Molecular Medicine (INFORMM), Universiti Sains Malaysia, 11800 Penang
| | - Norhidayu Sahimin
- Institute of Biological Science, Faculty of Science, University of Malaya, Kuala Lumpur, Malaysia
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Tsanglao WR, Nandan D, Chandelia S, Arya NK, Sharma A. Filarial tropical pulmonary eosinophilia: a condition masquerading asthma, a series of 12 cases. J Asthma 2018; 56:791-798. [PMID: 29969926 DOI: 10.1080/02770903.2018.1490748] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
INTRODUCTION Tropical pulmonary eosinophilia (TPE) is a form of occult filariasis, clinically characterized by paroxysmal cough, wheezing and dyspnea which is often misdiagnosed and treated as asthma. These manifestations result from a host immune response to trapped antigens of the microfilarial parasites Wuchereria bancrofti or Brugia malayi in the pulmonary microcirculation. CASE STUDY We describe three rare presentations of TPE (cor pumonale, cystic lung disease and respiratory distress mimicking acute severe asthma) in our series of 12 cases. All cases were from filaria endemic areas and presented with cough, wheezing and dyspnea, either alone or in combination. Subsequent work-up revealed peripheral eosinophilia, raised serum IgE levels and positive serum filarial antibody and/or antigen in all the cases. RESULTS All patients were treated with diethylcarbamazine (DEC), while few required inhaled/systemic corticosteroid. Prompt improvement in clinical symptoms with a decrease in eosinophil count was seen in all. Two cases relapsed requiring a second course of DEC. Long-term outcome was good, however, there was a persistence of restrictive lung function and echocardiographic feature of pulmonary hypertension in the patients with cystic lung disease and cor pulmonale, respectively. CONCLUSION TPE should always be considered in patients from filaria endemic areas presenting with cough, dyspnea or wheezing. High eosinophil count (>3 × 109 cells) with raised IgE level (>1000 IU/mL) in such cases should alert the physician to look for TPE. Early diagnosis and treatment can prevent disease progression and complications.
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Affiliation(s)
- Wonashi R Tsanglao
- a Department of Pediatrics , PGIMER, Dr.RML Hospital , New Delhi , India
| | - Devki Nandan
- a Department of Pediatrics , PGIMER, Dr.RML Hospital , New Delhi , India
| | - Sudha Chandelia
- a Department of Pediatrics , PGIMER, Dr.RML Hospital , New Delhi , India
| | | | - Anu Sharma
- a Department of Pediatrics , PGIMER, Dr.RML Hospital , New Delhi , India
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The design of target specific antibodies (scFv) by applying de novo workflow: Case study on BmR1 antigen from Brugia malayi. J Mol Graph Model 2017; 76:543-550. [DOI: 10.1016/j.jmgm.2017.07.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2017] [Revised: 06/02/2017] [Accepted: 07/05/2017] [Indexed: 11/24/2022]
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Pedram B, Pasquetto V, Drame PM, Ji Y, Gonzalez-Moa MJ, Baldwin RK, Nutman TB, Biamonte MA. A novel rapid test for detecting antibody responses to Loa loa infections. PLoS Negl Trop Dis 2017; 11:e0005741. [PMID: 28749939 PMCID: PMC5531435 DOI: 10.1371/journal.pntd.0005741] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Accepted: 06/23/2017] [Indexed: 01/06/2023] Open
Abstract
Ivermectin-based mass drug administration (MDA) programs have achieved remarkable success towards the elimination of onchocerciasis and lymphatic filariasis. However, their full implementation has been hindered in Central Africa by the occurrence of ivermectin-related severe adverse events (SAEs) in a subset of individuals with high circulating levels of Loa loa microfilariae. Extending MDA to areas with coincident L. loa infection is problematic, and inexpensive point-of-care tests for L. loa are acutely needed. Herein, we present a lateral flow assay (LFA) to identify subjects with a serological response to Ll-SXP-1, a specific and validated marker of L. loa. The test was evaluated on serum samples from patients infected with L. loa (n = 109) and other helminths (n = 204), as well as on uninfected controls (n = 77). When read with the naked eye, the test was 94% sensitive for L. loa infection and was 100% specific when sera from healthy endemic and non-endemic controls or from those with S. stercoralis infections were used as the comparators. When sera of patients with O. volvulus, W. bancrofti, or M. perstans were used as the comparators, the specificity of the LFA was 82%, 87%, and 88%, respectively. A companion smartphone reader allowed measurement of the test line intensities and establishment of cutoff values. With a cutoff of 600 Units, the assay sensitivity decreased to 71%, but the specificity increased to 96% for O. volvulus, 100% for W. bancrofti, and 100% for M. perstans-infected individuals. The LFA may find applications in refining the current maps of L. loa prevalence, which are needed to eliminate onchocerciasis and lymphatic filariasis from the African continent.
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Affiliation(s)
- Bijan Pedram
- Drugs & Diagnostics for Tropical Diseases, San Diego, California, United States of America
| | - Valérie Pasquetto
- Drugs & Diagnostics for Tropical Diseases, San Diego, California, United States of America
| | - Papa M. Drame
- Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Yongchang Ji
- Drugs & Diagnostics for Tropical Diseases, San Diego, California, United States of America
| | - Maria J. Gonzalez-Moa
- Drugs & Diagnostics for Tropical Diseases, San Diego, California, United States of America
| | | | - Thomas B. Nutman
- Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Marco A. Biamonte
- Drugs & Diagnostics for Tropical Diseases, San Diego, California, United States of America
- * E-mail:
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Circulating filarial antigen detection in brugian filariasis. Parasitology 2015; 143:350-7. [PMID: 26646772 DOI: 10.1017/s0031182015001675] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Human lymphatic filariasis (LF) is a major cause of disability globally. The success of global elimination programmes for LF depends upon effectiveness of tools for diagnosis and treatment. In this study on stage-specific antigen detection in brugian filariasis, L3, adult worm (AW) and microfilarial antigenaemia were detected in around 90-95% of microfilariae carriers (MF group), 50-70% of adenolymphangitis (ADL) patients, 10-25% of chronic pathology (CP) patients and 10-15% of endemic normal (EN) controls. The sensitivity of the circulating filarial antigen (CFA) detection in serum samples from MF group was up to 95%. In sera from ADL patients, unexpectedly, less antigen reactivity was observed. In CP group all the CFA positive individuals were from CP grade I and II only and none from grade III or IV, suggesting that with chronicity the AWs lose fecundity and start to disintegrate and die. Amongst EN subject, 10-15% had CFA indicating that few of them harbour filarial AWs, thus they might not be truly immune as has been conventionally believed. The specificity for antigen detection was 100% when tested with sera from various other protozoan and non-filarial helminthic infections.
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Khor BY, Tye GJ, Lim TS, Noordin R, Choong YS. The structure and dynamics of BmR1 protein from Brugia malayi: in silico approaches. Int J Mol Sci 2014; 15:11082-99. [PMID: 24950179 PMCID: PMC4100200 DOI: 10.3390/ijms150611082] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2014] [Revised: 03/25/2014] [Accepted: 06/04/2014] [Indexed: 12/27/2022] Open
Abstract
Brugia malayi is a filarial nematode, which causes lymphatic filariasis in humans. In 1995, the disease has been identified by the World Health Organization (WHO) as one of the second leading causes of permanent and long-term disability and thus it is targeted for elimination by year 2020. Therefore, accurate filariasis diagnosis is important for management and elimination programs. A recombinant antigen (BmR1) from the Bm17DIII gene product was used for antibody-based filariasis diagnosis in "Brugia Rapid". However, the structure and dynamics of BmR1 protein is yet to be elucidated. Here we study the three dimensional structure and dynamics of BmR1 protein using comparative modeling, threading and ab initio protein structure prediction. The best predicted structure obtained via an ab initio method (Rosetta) was further refined and minimized. A total of 5 ns molecular dynamics simulation were performed to investigate the packing of the protein. Here we also identified three epitopes as potential antibody binding sites from the molecular dynamics average structure. The structure and epitopes obtained from this study can be used to design a binder specific against BmR1, thus aiding future development of antigen-based filariasis diagnostics to complement the current diagnostics.
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Affiliation(s)
- Bee Yin Khor
- Institute for Research in Molecular Medicine, Universiti Sains Malaysia, Minden, Penang 11800, Malaysia.
| | - Gee Jun Tye
- Institute for Research in Molecular Medicine, Universiti Sains Malaysia, Minden, Penang 11800, Malaysia.
| | - Theam Soon Lim
- Institute for Research in Molecular Medicine, Universiti Sains Malaysia, Minden, Penang 11800, Malaysia.
| | - Rahmah Noordin
- Institute for Research in Molecular Medicine, Universiti Sains Malaysia, Minden, Penang 11800, Malaysia.
| | - Yee Siew Choong
- Institute for Research in Molecular Medicine, Universiti Sains Malaysia, Minden, Penang 11800, Malaysia.
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Transmission assessment surveys (TAS) to define endpoints for lymphatic filariasis mass drug administration: a multicenter evaluation. PLoS Negl Trop Dis 2013; 7:e2584. [PMID: 24340120 PMCID: PMC3855047 DOI: 10.1371/journal.pntd.0002584] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2013] [Accepted: 10/29/2013] [Indexed: 11/19/2022] Open
Abstract
Background Lymphatic filariasis (LF) is targeted for global elimination through treatment of entire at-risk populations with repeated annual mass drug administration (MDA). Essential for program success is defining and confirming the appropriate endpoint for MDA when transmission is presumed to have reached a level low enough that it cannot be sustained even in the absence of drug intervention. Guidelines advanced by WHO call for a transmission assessment survey (TAS) to determine if MDA can be stopped within an LF evaluation unit (EU) after at least five effective rounds of annual treatment. To test the value and practicality of these guidelines, a multicenter operational research trial was undertaken in 11 countries covering various geographic and epidemiological settings. Methodology The TAS was conducted twice in each EU with TAS-1 and TAS-2 approximately 24 months apart. Lot quality assurance sampling (LQAS) formed the basis of the TAS survey design but specific EU characteristics defined the survey site (school or community), eligible population (6–7 year olds or 1st–2nd graders), survey type (systematic or cluster-sampling), target sample size, and critical cutoff (a statistically powered threshold below which transmission is expected to be no longer sustainable). The primary diagnostic tools were the immunochromatographic (ICT) test for W. bancrofti EUs and the BmR1 test (Brugia Rapid or PanLF) for Brugia spp. EUs. Principal Findings/Conclusions In 10 of 11 EUs, the number of TAS-1 positive cases was below the critical cutoff, indicating that MDA could be stopped. The same results were found in the follow-up TAS-2, therefore, confirming the previous decision outcome. Sample sizes were highly sex and age-representative and closely matched the target value after factoring in estimates of non-participation. The TAS was determined to be a practical and effective evaluation tool for stopping MDA although its validity for longer-term post-MDA surveillance requires further investigation. Lymphatic filariasis (LF) is targeted for global elimination through a strategy of repeated annual mass drug administration (MDA) to entire at-risk populations. A transmission assessment survey (TAS) is designed to evaluate whether transmission of LF is presumed to have reached a level low enough that it cannot be sustained in the absence of drug intervention and, therefore, MDA can be stopped. This multicenter operational research trial examines the value and practicality of the TAS guidelines through its implementation in 11 countries of diverse geographical and epidemiologic profiles. The field experiences support the TAS survey design methodology with particular respect to school and cluster-based sampling strategies. We found that sample sizes were age and sex representative and met the target values after factoring in estimates of non-participation rates. In 10 of 11 countries, the TAS found the number of positive cases in the evaluation unit to be no more than the statistically powered critical threshold. These results were corroborated in a follow-up TAS approximately 24 months later. We conclude the TAS is a valuable and effective tool for stopping MDA but its utility for longer-term post-MDA surveillance needs further empirical evidence and may be best supported with complementary tools and methods.
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Metenou S, Nutman TB. Regulatory T cell subsets in filarial infection and their function. Front Immunol 2013; 4:305. [PMID: 24137161 PMCID: PMC3786323 DOI: 10.3389/fimmu.2013.00305] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2013] [Accepted: 09/13/2013] [Indexed: 01/11/2023] Open
Abstract
Filarial infections in humans are chronic infections that cause significant morbidity. The chronic nature of these infections with continuous antigen release is associated with a parasite-specific T cell hypo-responsiveness that may over time also affect the immune responses to bystander antigens. Previous studies have shown the filarial parasite antigen-specific T cells hypo-responsiveness is mediated by regulatory cytokines – IL-10 and TGF-β in particular. Recent studies have suggested that the modulated/regulated T cell responses associated with patent filarial infection may reflect an expansion of regulatory T cells (Tregs) that include both Tregs induced in peripheral circulation or pTregs and the thymus-derived Tregs or tTregs. Although much is known about the phenotype of these regulatory populations, the mechanisms underlying their expansion and their mode of action in filarial and other infections remain unclear. Nevertheless there are data to suggest that while many of these regulatory cells are activated in an antigen-specific manner the ensuing effectors of this activation are relatively non-specific and may affect a broad range of immune cells. This review will focus on the subsets and function of regulatory T cells in filarial infection.
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Affiliation(s)
- Simon Metenou
- Helminth Immunology Section, Laboratory of Parasitic Diseases, National Institutes of Health , Bethesda, MD , USA
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Joseph S, Verma S, Sahoo M, Sharma A, Srivastava M, Reddy M, Murthy P. IgG subclass responses to proinflammatory fraction of Brugia malayi in human filariasis. Indian J Med Res 2012; 135:650-5. [PMID: 22771594 PMCID: PMC3401695] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/24/2010] [Indexed: 11/05/2022] Open
Abstract
BACKGROUND & OBJECTIVES Earlier we demonstrated that immunization with F6, a proinflammatory molecular fraction isolated from the human filarial parasite Brugia malayi, protected the host and eliminated the infection in Mastomys coucha by a Th1/Th2 response including IgG2a antibody response. Whether F6 molecules become accessible to human host during natural course of infection and elicit similar response is not known. The present study was undertaken to determine the profile of IgG subclasses specifically reactive to F6 in different categories of bancroftian filariasis cases to infer any relationship between the levels of a particular F6-specific IgG subclass and the infection or disease status. METHODS Serum samples of normal individuals from filariasis non-endemic regions of India like Jammu & Kashmir, Uttarakhand, and Chandigarh [(NEN-W; n=10), healthy subjects from USA (NEN-U; n=10) and three categories of bancroftian filariasis cases from endemic areas: endemic normals (EN; n=10) with no symptoms and no microfilariae, asymptomatic microfilaremics (ASM; n=10) and chronic symptomatic amicrofilaremics (CL; n=10) were assayed for F6-specific IgG1, IgG2, IgG3 and IgG4 by ELISA using SDS-PAGE-isolated F6 fraction of B. malayi adult worms. RESULTS Significantly high levels of F6-specific IgG1, IgG2 and IgG3 were found in CL (P<0.001) and EN (P<0.01-0.001) bancroftian filariasis cases compared to NEN-U. Significant levels of F6-specific IgG1 (P<0.01) and IgG2 (P<0.01) but not IgG3 were found in ASM cases compared to NEN-U. The most abundant was IgG2 which when compared to NEN-U, was significantly high in CL (P<0.001) and EN cases (P<0.001), followed by ASM (P<0.01). F6-specific IgG4 response in EN, ASM and CL subjects was not significantly different from the levels of NEN-U. Among the non-endemic normals, the NEN-W subjects showed significant reactivity with IgG2 (P<0.001) but not with IgG1, IgG3 and IgG4 as compared to NEN-U subjects. IgG subclass levels were different in different categories. INTERPRETATION & CONCLUSIONS The high levels of F6 reactive IgG1, IgG2 and IgG3 in endemic normals and chronic symptomatic bancroftian patients, and IgG1 and IgG2 in asymptomatic microfilaraemics, suggest that F6 molecules of parasite are accessible in these subjects for IgG subclass-specific immune response and IgG2 may be related to pathogenesis. Studies using individual F6 molecules will be done to identify the molecule(s) involved in infection and protective immunity.
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Affiliation(s)
- S.K. Joseph
- Division of Parasitology, CSIR-Central Drug Research Institute, Lucknow, India
| | - S.K. Verma
- Division of Parasitology, CSIR-Central Drug Research Institute, Lucknow, India
| | - M.K. Sahoo
- Division of Parasitology, CSIR-Central Drug Research Institute, Lucknow, India
| | - A. Sharma
- Division of Parasitology, CSIR-Central Drug Research Institute, Lucknow, India
| | - M. Srivastava
- Division of Biometry & Statistics, CSIR-Central Drug Research Institute, Lucknow, India
| | - M.V.R. Reddy
- Department of Biochemistry & JB Tropical Disease Research Centre, Mahatma Gandhi Institute of Medical Sciences, Sevagram, India
| | - P.K. Murthy
- Division of Parasitology, CSIR-Central Drug Research Institute, Lucknow, India
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Athisaya Mary K, Hoti SL, Krishnamoorthy K, Das PK, Rahmah N. Detection of filarial specific IgG4 antibodies in individuals residing in endemic areas using panLFRAPID test card. J Parasit Dis 2011; 35:77-9. [DOI: 10.1007/s12639-011-0021-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2010] [Accepted: 01/26/2011] [Indexed: 10/18/2022] Open
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