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A MAPS Vaccine Induces Multipronged Systemic and Tissue-Resident Cellular Responses and Protects Mice against Mycobacterium tuberculosis. mBio 2023; 14:e0361122. [PMID: 36749098 PMCID: PMC9973048 DOI: 10.1128/mbio.03611-22] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Tuberculosis (TB) remains a leading cause of morbidity and mortality worldwide. To date, the mainstay of vaccination involves the use of Mycobacterium bovis bacillus Calmette-Guérin (BCG), a live-attenuated vaccine that confers protection against extrapulmonary disease in infants and children but not against lung disease. Thus, there is an urgent need for novel vaccines. Here, we show that a multicomponent acellular vaccine (TB-MAPS) induces robust antibody responses and long-lived systemic and tissue-resident memory Th1, Th17, and cytotoxic CD4+ and CD8+ T cells, and promotes trained innate immunity mediated by γδT and NKT cells in mice. When tested in a mouse aerosol infection model, TB-MAPS significantly reduced bacterial loads in the lungs and spleens to the same extent as BCG. When used in conjunction with BCG, TB-MAPS further enhanced BCG-mediated protection, especially in the lungs, further supporting this construct as a promising TB vaccine candidate. IMPORTANCE Tuberculosis (TB) remains a leading cause of morbidity and mortality worldwide. Here, we evaluate a novel vaccine which induces a broad immune response to Mycobacterium tuberculosis including robust antibody responses and long-lived systemic and tissue-resident memory Th1, Th17, and cytotoxic CD4+ and CD8+ T cells. When tested in a mouse aerosol infection model, this vaccine significantly reduced bacterial loads in the lungs and spleens to the same extent as BCG. When used in conjunction with BCG, TB-MAPS further enhanced BCG-mediated protection, especially in the lungs, further supporting this construct as a promising TB vaccine candidate.
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Zagmignan A, Costa ACD, Viana JL, Lima Neto LG, Monteiro CDA, Gaioso Neto AG, Junqueira-Kipnis AP, de Sousa EM. Identification of specific antibodies against the Ag85C-MPT51-HspX fusion protein (CMX) for serological screening of tuberculosis in endemic area. Expert Rev Clin Immunol 2017. [PMID: 28633546 DOI: 10.1080/1744666x.2017.1345626] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
OBJECTIVES Development of new tools for rapid and accurate diagnosis of tuberculosis (TB) is considered a strategy for controlling the disease. The recombinant CMX fusion protein is composed of immunodominant epitopes of the Ag85C (Rv0129c), MPT51 (Rv3803c) and the entire HspX (Rv2031c) proteins from Mycobacterium tuberculosis H37Rv (Mtb). The aim of this study was to evaluate the applicability of a test using the CMX protein in individuals suspected of TB. METHODS Indirect ELISA was used to measure serum anti-CMX IgM and IgG in individuals with pulmonary TB. RESULTS Patients with pulmonary TB had higher titers of IgM (OD = 0.502 ± 0.281) than healthy controls (OD = 0.200 ± 0.125). The cutoff for IgM-ELISA was determined using ROC curve analyzes (AUC = 0.868) with a sensitivity of 80.1% and a specificity of 78.2%. Patients with pulmonary TB also had higher titers of IgG (OD = 0.525 ± 0.391) than healthy controls (OD = 0.215 ± 0.077). The cutoff for IgG-ELISA was determined using ROC curve analyzes (AUC = 0.864) with a sensitivity of 81.7% and a specificity of 74.7%. CONCLUSION The results suggest that the recombinant protein CMX can be used in a serological test to complement the screening of individuals suspected of having active pulmonary TB.
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Affiliation(s)
- Adrielle Zagmignan
- a Programa de Pós-graduação , Universidade Ceuma , São Luis , MA , Brazil
| | - Adeliane Castro da Costa
- b Universidade Federal de Goias- Laboratory of Immunopathology of Infectious Disease, Department of Microbiology , Immunology, Parasitology and Pathology, Institute of Tropical Disease and Public Health , Goiania , Brazil
| | - José Lima Viana
- a Programa de Pós-graduação , Universidade Ceuma , São Luis , MA , Brazil
| | | | | | | | - Ana Paula Junqueira-Kipnis
- b Universidade Federal de Goias- Laboratory of Immunopathology of Infectious Disease, Department of Microbiology , Immunology, Parasitology and Pathology, Institute of Tropical Disease and Public Health , Goiania , Brazil
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Alves Da Silva D, Cavalcanti MAR, Muniz De Oliveira F, Trentini MM, Junqueira-Kipnis AP, Kipnis A. Immunogenicity of a recombinant Mycobacterium smegmatis vaccine expressing the fusion protein CMX in cattle from Goiás State, Brazil. J Vet Med Sci 2014; 76:977-84. [PMID: 24681608 PMCID: PMC4143659 DOI: 10.1292/jvms.13-0338] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
This study aimed to evaluate the immunogenicity of a recombinant Mycobacterium smegmatis vaccine expressing the CMX fusion protein composed of immunodominant epitopes Ag85C, MPT51 and HspX of Mycobacterium tuberculosis, which are important mycobacteria virulence factors. A group of Nelore heifers that were 10 to 12 months of age and negative for the tuberculin skin test (TST) were immunized with four doses of the recombinant vaccine mc(2)-CMX (M. smegmatis-Ag85C-MPT51-HspX) during a period of one year. Before each immunization, blood was collected to obtain sera for antibody analysis. Serological analysis demonstrated that mc(2)-CMX was able to induce a humoral response with increased levels of specific IgG antibodies against CMX, despite minimum antibody levels being detected for individual Ag85C, MPT51 or HspX recombinant antigens. However, there was no significant increase in specific CD4(+) IFN-γ-positive T cells. Lymphadenomegaly was observed in superficial cervical lymph nodes adjacent to the site of vaccination among mc(2)-CMX-vaccinated bovines, and the histopathological analysis demonstrated follicular hyperplasia without inflammatory infiltrate or granuloma formation. Animals remained negative for the TST until the end of the experiments, showing no cross-reactivity with the recombinant vaccine and tuberculin proteins. We discuss the potential of mc(2)-CMX to induce an immune response in cattle.
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Affiliation(s)
- Duanne Alves Da Silva
- Tropical Pathology and Public Health Institute, Federal University of Goiás, Rua 235 esquina com 1a Avenida, Setor Universitário, Goiânia, Goiás, CEP 74605-050, Brazil
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Silva BDDS, Trentini MM, da Costa AC, Kipnis A, Junqueira-Kipnis AP. Different phenotypes of CD8+ T cells associated with bacterial load in active tuberculosis. Immunol Lett 2014; 160:23-32. [PMID: 24694750 DOI: 10.1016/j.imlet.2014.03.009] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2014] [Revised: 03/20/2014] [Accepted: 03/21/2014] [Indexed: 12/22/2022]
Abstract
Tuberculosis is an infectious disease that affects millions of people worldwide with an annual mortality rate of 1.3 million. The mechanisms contributing to the loss of balance of immune responses and progression to active tuberculosis disease are unknown. Although CD4+ and CD8+ T cells and the cytokines they produce are crucial for protection against tuberculosis they have different roles in tuberculosis immunology. The function of CD4+ T cells has been extensively studied; however, less is known about the phenotype and function of CD8+ T cells. This study evaluated the specific expression of IFN-γ, IL-17, IL-10, and TGF-β and ex vivo expression of perforin and granzyme-B by CD8+ T cells from active tuberculosis individuals compared with latent infected individuals and non-latent infected individuals. Tuberculosis responses were correlated with the baciloscopy score. We observed that the presence of IL-10 and TGF-β expression and down-expression of granzyme-B in CD8+ T cells correlated with increased sputum bacillary load in active tuberculosis individuals. These findings provide new insights into the role of CD8+ T cells in Mycobacterium tuberculosis disease.
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Affiliation(s)
- Bruna Daniella de Souza Silva
- Department of Microbiology, Immunology, Parasitology and Pathology, Tropical Pathology and Public Health Institute, Federal University of Goiás, Goiânia, Goiás, Brazil
| | - Monalisa Martins Trentini
- Department of Microbiology, Immunology, Parasitology and Pathology, Tropical Pathology and Public Health Institute, Federal University of Goiás, Goiânia, Goiás, Brazil
| | - Adeliane Castro da Costa
- Department of Microbiology, Immunology, Parasitology and Pathology, Tropical Pathology and Public Health Institute, Federal University of Goiás, Goiânia, Goiás, Brazil
| | - Andre Kipnis
- Department of Microbiology, Immunology, Parasitology and Pathology, Tropical Pathology and Public Health Institute, Federal University of Goiás, Goiânia, Goiás, Brazil
| | - Ana Paula Junqueira-Kipnis
- Department of Microbiology, Immunology, Parasitology and Pathology, Tropical Pathology and Public Health Institute, Federal University of Goiás, Goiânia, Goiás, Brazil.
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Ashraf S, Saqib MAN, Sharif MZ, Khatak AA, Khan SN, Malik SA, Tahseen S, Khanum A. EVALUATION OF DIAGNOSTIC POTENTIAL OF Rv3803c AND Rv2626c RECOMBINANT ANTIGENS IN TB ENDEMIC COUNTRY PAKISTAN. J Immunoassay Immunochem 2013; 35:120-9. [DOI: 10.1080/15321819.2013.824897] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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Junqueira-Kipnis AP, de Oliveira FM, Trentini MM, Tiwari S, Chen B, Resende DP, Silva BDS, Chen M, Tesfa L, Jacobs WR, Kipnis A. Prime-boost with Mycobacterium smegmatis recombinant vaccine improves protection in mice infected with Mycobacterium tuberculosis. PLoS One 2013; 8:e78639. [PMID: 24250805 PMCID: PMC3826754 DOI: 10.1371/journal.pone.0078639] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2013] [Accepted: 09/21/2013] [Indexed: 02/06/2023] Open
Abstract
The development of a new vaccine as a substitute for Bacillus Calmette-Guerin or to improve its efficacy is one of the many World Health Organization goals to control tuberculosis. Mycobacterial vectors have been used successfully in the development of vaccines against tuberculosis. To enhance the potential utility of Mycobacterium smegmatis as a vaccine, it was transformed with a recombinant plasmid containing the partial sequences of the genes Ag85c, MPT51, and HspX (CMX) from M. tuberculosis. The newly generated recombinant strain mc(2)-CMX was tested in a murine model of infection. The recombinant vaccine induced specific IgG1 or IgG2a responses to CMX. CD4(+) and CD8(+) T cells from the lungs and spleen responded ex vivo to CMX, producing IFN-γ, IL17, TNF-α, and IL2. The vaccine thus induced a significant immune response in mice. Mice vaccinated with mc(2)-CMX and challenged with M. tuberculosis showed better protection than mice immunized with wild-type M. smegmatis or BCG. To increase the safety and immunogenicity of the CMX antigens, we used a recombinant strain of M. smegmatis, IKE (immune killing evasion), to express CMX. The recombinant vaccine IKE-CMX induced a better protective response than mc(2)-CMX. The data presented here suggest that the expression of CMX antigens improves the immune response and the protection induced in mice when M. smegmatis is used as vaccine against tuberculosis.
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Affiliation(s)
- Ana Paula Junqueira-Kipnis
- Instituto de Patologia Tropical e Saúde Pública. Universidade Federal de Goiás, Goiânia, Goiás, Brazil
- * E-mail:
| | - Fábio Muniz de Oliveira
- Instituto de Patologia Tropical e Saúde Pública. Universidade Federal de Goiás, Goiânia, Goiás, Brazil
| | - Monalisa Martins Trentini
- Instituto de Patologia Tropical e Saúde Pública. Universidade Federal de Goiás, Goiânia, Goiás, Brazil
| | - Sangeeta Tiwari
- Microbiology and Immunology, Molecular Genetics, Albert Einstein College of Medicine, New York, New York, United States of America
| | - Bing Chen
- Microbiology and Immunology, Molecular Genetics, Albert Einstein College of Medicine, New York, New York, United States of America
| | - Danilo Pires Resende
- Instituto de Patologia Tropical e Saúde Pública. Universidade Federal de Goiás, Goiânia, Goiás, Brazil
| | - Bruna D. S. Silva
- Instituto de Patologia Tropical e Saúde Pública. Universidade Federal de Goiás, Goiânia, Goiás, Brazil
| | - Mei Chen
- Microbiology and Immunology, Molecular Genetics, Albert Einstein College of Medicine, New York, New York, United States of America
| | - Lydia Tesfa
- Microbiology and Immunology, Molecular Genetics, Albert Einstein College of Medicine, New York, New York, United States of America
- Flow Cytometry Core Facility, Albert Einstein College of Medicine, New York, New York, United States of America
| | - William R. Jacobs
- Microbiology and Immunology, Molecular Genetics, Albert Einstein College of Medicine, New York, New York, United States of America
| | - André Kipnis
- Instituto de Patologia Tropical e Saúde Pública. Universidade Federal de Goiás, Goiânia, Goiás, Brazil
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de Sousa EM, da Costa AC, Trentini MM, de Araújo Filho JA, Kipnis A, Junqueira-Kipnis AP. Immunogenicity of a fusion protein containing immunodominant epitopes of Ag85C, MPT51, and HspX from Mycobacterium tuberculosis in mice and active TB infection. PLoS One 2012; 7:e47781. [PMID: 23133523 PMCID: PMC3485045 DOI: 10.1371/journal.pone.0047781] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2012] [Accepted: 09/17/2012] [Indexed: 12/29/2022] Open
Abstract
Tuberculosis (TB) remains a major global health problem. The only vaccine against tuberculosis, attenuated Mycobacterium bovis Bacillus Calmette-Guerin (BCG), has demonstrated relatively low efficacy and does not provide satisfactory protection against the disease in adults. More effective vaccines and better therapies are urgently needed to reduce the global spread of TB. This study evaluated the immunogenicity of a recombinant M. tuberculosis Ag85C-MPT51-HspX fusion protein (CMX) in mice and individuals with active tuberculosis. BALB/c mice were immunized with the CMX protein liposome-encapsulated with CpG DNA or with CpGDNA liposome-encapsulated, liposome or saline as negative controls. The immunization produced high levels of anti-CMX -specific IgG1 and IgG2a antibodies and induced an increase in the relative and absolute numbers of specific TCD4 IFN-γ+ and TNF-α+ cells in the spleen. Sera from a cohort of individuals with active tuberculosis contained higher levels of IgG and IgM that recognized CMX when compared to healthy individuals. In conclusion, this protein was shown to be immunogenic both in mice and humans.
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Affiliation(s)
- Eduardo Martins de Sousa
- Instituto de Patologia Tropical e Saúde Pública, Universidade Federal de Goiás, Goiânia, Goiás, Brazil
| | - Adeliane Castro da Costa
- Instituto de Patologia Tropical e Saúde Pública, Universidade Federal de Goiás, Goiânia, Goiás, Brazil
| | - Monalisa Martins Trentini
- Instituto de Patologia Tropical e Saúde Pública, Universidade Federal de Goiás, Goiânia, Goiás, Brazil
| | | | - André Kipnis
- Instituto de Patologia Tropical e Saúde Pública, Universidade Federal de Goiás, Goiânia, Goiás, Brazil
| | - Ana Paula Junqueira-Kipnis
- Instituto de Patologia Tropical e Saúde Pública, Universidade Federal de Goiás, Goiânia, Goiás, Brazil
- * E-mail:
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Limongi LCSA, Olival L, Conde MB, Junqueira-Kipnis AP. Pesquisa de IgA contra o antígeno recombinante HspX de Mycobacterium tuberculosis no diagnóstico de tuberculose pleural. J Bras Pneumol 2011; 37:302-7. [DOI: 10.1590/s1806-37132011000300005] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2011] [Accepted: 03/21/2011] [Indexed: 11/21/2022] Open
Abstract
OBJETIVO: Avaliar a acurácia da dosagem de IgA contra o antígeno recombinante HspX no líquido pleural e no soro de pacientes com derrame pleural para o diagnóstico de tuberculose pleural. MÉTODOS: Estudo transversal de teste diagnóstico. Amostras de líquido pleural e de soro de pacientes com derrame pleural e suspeita de tuberculose pleural foram avaliadas para a determinação da densidade óptica de IgA contra HspX utilizando ELISA indireto. RESULTADOS: Foram avaliadas amostras de líquido pleural e de soro de 132 pacientes: 97 com tuberculose pleural (grupo de estudo) e 35 com derrame pleural por outras causas (grupo controle). A dosagem de IgA em líquido pleural foi capaz de discriminar os pacientes com tuberculose pleural dos controles. A sensibilidade do teste em líquido pleural e em soro foi, respectivamente, de 69% e 30%, enquanto a especificidade foi de 83% e 84%, respectivamente. CONCLUSÕES: Os dados sugerem o potencial da utilização deste teste no diagnóstico de tuberculose pleural. Estudos com amostras maiores e em diferentes cenários epidemiológicos são necessários
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Dunn MF, Ramírez-Trujillo JA, Hernández-Lucas I. Major roles of isocitrate lyase and malate synthase in bacterial and fungal pathogenesis. MICROBIOLOGY-SGM 2009; 155:3166-3175. [PMID: 19684068 DOI: 10.1099/mic.0.030858-0] [Citation(s) in RCA: 198] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The glyoxylate cycle is an anaplerotic pathway of the tricarboxylic acid (TCA) cycle that allows growth on C(2) compounds by bypassing the CO(2)-generating steps of the TCA cycle. The unique enzymes of this route are isocitrate lyase (ICL) and malate synthase (MS). ICL cleaves isocitrate to glyoxylate and succinate, and MS converts glyoxylate and acetyl-CoA to malate. The end products of the bypass can be used for gluconeogenesis and other biosynthetic processes. The glyoxylate cycle occurs in Eukarya, Bacteria and Archaea. Recent studies of ICL- and MS-deficient strains as well as proteomic and transcriptional analyses show that these enzymes are often important in human, animal and plant pathogenesis. These studies have extended our understanding of the metabolic pathways essential for the survival of pathogens inside the host and provide a more complete picture of the physiology of pathogenic micro-organisms. Hopefully, the recent knowledge generated about the role of the glyoxylate cycle in virulence can be used for the development of new vaccines, or specific inhibitors to combat bacterial and fungal diseases.
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Affiliation(s)
- M F Dunn
- Centro de Ciencias Genómicas, Universidad Nacional Autónoma de México, Cuernavaca, Morelos 62210, Mexico
| | - J A Ramírez-Trujillo
- Centro de Ciencias Genómicas, Universidad Nacional Autónoma de México, Cuernavaca, Morelos 62210, Mexico
| | - I Hernández-Lucas
- Departamento de Microbiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, Morelos 62210, Mexico
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Silva BDDS, da Silva EB, do Nascimento IP, dos Reis MCG, Kipnis A, Junqueira-Kipnis AP. MPT-51/CpG DNA vaccine protects mice against Mycobacterium tuberculosis. Vaccine 2009; 27:4402-7. [DOI: 10.1016/j.vaccine.2009.05.049] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2009] [Revised: 05/06/2009] [Accepted: 05/14/2009] [Indexed: 11/16/2022]
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de Araújo-Filho JA, Vasconcelos AC, Martins de Sousa E, Kipnis A, Ribeiro E, Junqueira-Kipnis AP. Cellular responses to MPT-51, GlcB and ESAT-6 among MDR-TB and active tuberculosis patients in Brazil. Tuberculosis (Edinb) 2008; 88:474-81. [PMID: 18676203 DOI: 10.1016/j.tube.2008.06.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2008] [Revised: 05/19/2008] [Accepted: 06/02/2008] [Indexed: 11/24/2022]
Abstract
Multi-drug resistant pulmonary tuberculosis (MDR-TB) may result from either insufficiency of the host cellular immune response or mycobacterial mechanisms of resistance. Mycobacterium tuberculosis-specific CD8+ and CD4+ T lymphocytes from MDR-TB patients are poorly studied. The aim of this study was to evaluate CD4+IFN-gamma+, CD4+IL-10+, CD8(+)IFN-gamma+ and CD8+IL-10+ cell populations by flow cytometry in non-resistant TB and multi-drug resistant tuberculosis (MDR-TB) patients from mid-central Brazil after stimulation with MPT-51, GlcB and ESAT-6 recombinant antigens from M. tuberculosis in comparison to tuberculin skin test negative (TST) healthy individuals. Non-resistant TB patients present specific cellular responses (CD4 and CD8, both IFN-gamma and IL-10) to GlcB, MPT-51 and ESAT-6; while MDR-TB patients present only CD8+IFN-gamma+ responses to ESAT-6 and CD8+IL-10+ responses to GlcB and ESAT-6. The results show that MDR-TB patients present impaired specific CD4 IFN-gamma and IL-10 responses and increased/normal specific CD8 IFN-gamma and IL-10 responses. This suggests an important role for CD8 function in these patients.
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Affiliation(s)
- João Alves de Araújo-Filho
- Instituto de Patologia Tropical e Saúde Pública, Universidade Federal de Goiás, Rua Delenda Rezende de Melo, S/No, Setor Universitário, Goiânia, Brazil
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Bego MG, Bawiec D, Dandge D, Martino B, Dearing D, Wilson E, St Jeor S. Development of an ELISA to detect Sin Nombre virus-specific IgM from deer mice (Peromyscus maniculatus). J Virol Methods 2008; 151:204-210. [PMID: 18586333 DOI: 10.1016/j.jviromet.2008.05.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2007] [Revised: 04/11/2008] [Accepted: 05/12/2008] [Indexed: 11/28/2022]
Abstract
Peromyscus maniculatus (deer mouse) is the primary reservoir for Sin Nombre virus (SNV). Although the presence of IgG antibodies is often used as a marker of infection, it provides little information on active infections in a population but usually is an indicator of past infections. The presence of IgM antibodies is a much better marker for determining whether active infections are present in a population. A mu-capture SNV-specific IgM enzyme linked immunosorbent assay (ELISA) was developed. From live-trap and release studies a total of 68 rodent sera were studied for the presence of Sin Nombre virus-specific IgG and IgM antibodies. In these studies, IgM responses were detected in a number of animals. In some cases early SNV infection was determined through the presence of anti-SNV IgM before IgG antibodies could be detected. From the set of animals analyzed, it was concluded that the IgM response against SNV can persist anywhere from 1 to up to over 2 months, with a median of less than 1 month. Most importantly, it was demonstrated that anti-Sin Nombre virus IgM is an important tool for detection of early infections in rodents and should be considered as a key diagnostic tool.
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Affiliation(s)
- Mariana G Bego
- University of Nevada, Reno, School of Medicine, Department of Microbiology, 1664 N Virginia St. MS 200, Reno, NV 89557, USA.
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