Comparative Analysis of B- and T-Cell Epitopes of Mycobacterium leprae and Mycobacterium tuberculosis Culture Filtrate Protein 10

ABSTRACT Culture filtrate protein 10 (CFP-10) from Mycobacterium tuberculosis is a well-characterized immunodominant 10-kDa protein antigen known to elicit a very potent early gamma interferon response in T cells from M. tuberculosis-infected mice and humans. The sequence of the Mycobacterium leprae homologue of CFP-10 shows only 40% identity (60% homology) at the protein level with M. tuberculosis CFP-10 and thus has the potential for development as a T- or B-cell reactive antigen for specific diagnosis of leprosy. Antisera raised in mice or rabbits against recombinant M. leprae and M. tuberculosis CFP-10 proteins reacted only with homologous peptides from arrays of overlapping synthetic peptides, indicating that there was no detectable cross-reactivity at the antibody level. Sera from leprosy and tuberculosis patients were also specific for the homologous protein or peptides and showed distinct patterns of recognition for either M. leprae or M. tuberculosis CFP-10 peptides. At the cellular level, only 2 of 45 mouse T-cell hybridomas raised against either M. leprae or M. tuberculosis CFP-10 displayed a cross-reactive response against the N-terminal heterologous CFP-10 peptide, the region that exhibits the highest level of identity in the two proteins; however, the majority of peptide epitopes recognized by mouse T-cell hybridomas specific for each protein did not cross-react with heterologous peptides. Coupled with the human serology data, these results raise the possibility that peptides that could be used to differentiate infections caused by these two related microorganisms could be developed. Immunohistochemical staining of sections of M. leprae-infected nude mouse footpads resulted in strongly positive staining in macrophages and dendritic cells, as well as weaker staining in extracellular areas, suggesting that M. leprae CFP-10, like its homologue in M. tuberculosis, is a secreted protein.

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Antigenic Specificity of the Mycobacterium leprae Homologue of ESAT-6

Infection and Immunity ◽

10.1128/iai.70.2.1010-1013.2002 ◽

2002 ◽

Vol 70 (2) ◽

pp. 1010-1013 ◽

Cited By ~ 25

Author(s):

John S. Spencer ◽

Maria Angela M. Marques ◽

Monica C. B. S. Lima ◽

Ana Paula Junqueira-Kipnis ◽

Bruce C. Gregory ◽

...

Keyword(s):

Cell Wall ◽

Mycobacterium Tuberculosis ◽

Monoclonal Antibodies ◽

T Cell ◽

Mycobacterium Leprae ◽

Antigenic Specificity ◽

Cell Wall Fraction ◽

T Cell Epitopes ◽

Homologous Protein ◽

Diagnostic Agent

ABSTRACT The sequence of the Mycobacterium leprae homologue of ESAT-6 shows only 36% amino acid correspondence to that from Mycobacterium tuberculosis. Anti-M. leprae ESAT-6 polyclonal and monoclonal antibodies and T-cell hybridomas reacted only with the homologous protein and allowed identification of the B- and T-cell epitopes. The protein is expressed in M. leprae and appears in the cell wall fraction. Thus, M. leprae ESAT-6 shows promise as a specific diagnostic agent for leprosy.

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Highly conserved, non-human-like, and cross-reactive SARS-CoV-2 T cell epitopes for COVID-19 vaccine design and validation

npj Vaccines ◽

10.1038/s41541-021-00331-6 ◽

2021 ◽

Vol 6 (1) ◽

Author(s):

Lauren M. Meyers ◽

Andres H. Gutiérrez ◽

Christine M. Boyle ◽

Frances Terry ◽

Bethany G. McGonnigal ◽

...

Keyword(s):

T Cell ◽

Cross Reactivity ◽

Binding Potential ◽

T Cell Epitopes ◽

Block Transmission ◽

Peptide Epitopes ◽

Specific Memory ◽

Cell Immunity ◽

Mouse Immunization ◽

Hla Binding

AbstractNatural and vaccine-induced SARS-CoV-2 immunity in humans has been described but correlates of protection are not yet defined. T cells support the SARS-CoV-2 antibody response, clear virus-infected cells, and may be required to block transmission. In this study, we identified peptide epitopes associated with SARS-CoV-2 T-cell immunity. Using immunoinformatic methods, T-cell epitopes from spike, membrane, and envelope were selected for maximal HLA-binding potential, coverage of HLA diversity, coverage of circulating virus, and minimal potential cross-reactivity with self. Direct restimulation of PBMCs collected from SARS-CoV-2 convalescents confirmed 66% of predicted epitopes, whereas only 9% were confirmed in naive individuals. However, following a brief period of epitope-specific T-cell expansion, both cohorts demonstrated robust T-cell responses to 97% of epitopes. HLA-DR3 transgenic mouse immunization with peptides co-formulated with poly-ICLC generated a potent Th1-skewed, epitope-specific memory response, alleviating safety concerns of enhanced respiratory disease associated with Th2 induction. Taken together, these epitopes may be used to improve our understanding of natural and vaccine-induced immunity, and to facilitate the development of T-cell-targeted vaccines that harness pre-existing SARS-CoV-2 immunity.

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Mycobacterium tuberculosis Culture Filtrate Protein 10-Specific Effector/Memory CD4+and CD8+T Cells in Tubercular Pleural Fluid, with Biased Usage of T Cell Receptor Vβ Chains

Infection and Immunity ◽

10.1128/iai.00014-11 ◽

2011 ◽

Vol 79 (8) ◽

pp. 3358-3365 ◽

Cited By ~ 12

Author(s):

Dan Qiao ◽

Li Li ◽

Jian Guo ◽

Suihua Lao ◽

Xianlan Zhang ◽

...

Keyword(s):

Immune Response ◽

T Cells ◽

Mycobacterium Tuberculosis ◽

T Cell ◽

Pleural Fluid ◽

Culture Filtrate ◽

T Cell Subsets ◽

Effector Memory ◽

Content Type ◽

Culture Filtrate Protein

ABSTRACTT cell-mediated immunity is critical for the control ofMycobacterium tuberculosisinfection. Identifying the precise immune mechanisms that lead to control of initialM. tuberculosisinfection and preventing reactivation of latent infection are crucial for combating tuberculosis. However, a detailed understanding of the role of T cells in the immune response to infection has been hindered. In addition, there are few flow cytometry studies characterizing the Vβ repertoires of T cell receptors (TCRs) at local sites ofM. tuberculosisinfection in adult tuberculosis. In this study, we used culture filtrate protein 10 (CFP-10) fromM. tuberculosisto characterize T cells at local sites of infection. We simultaneously analyzed the correlation of the production of cytokines with TCR Vβ repertoires in CFP-10-specific CD4+and CD8+T cell subsets. For the first time, we demonstrate that CFP-10-specific CD4+or CD8+T cells from tubercular pleural fluid can produce high levels of gamma interferon (IFN-γ) and tumor necrosis factor alpha (TNF-α) and upregulate the expression of CD107a/b on the cell surface. The CFP-10-specific cells were effector/memory cells with a CD45RO+CD62L−CCR7−CD27−expression profile. In addition, we found CFP-10-specific CD4+and CD8+T cells in tubercular pleural fluid, with biased usage of TCR Vβ9, Vβ12, or Vβ7.2. Our findings of CFP-10-specific CD4+and CD8+T cells in tubercular pleural fluid are critical for understanding the mechanisms of the local cellular immune response and developing more effective therapeutic interventions in cases ofM. tuberculosisinfection.

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Pulmonary delivery of chitosan-DNA nanoparticles enhances the immunogenicity of a DNA vaccine encoding HLA-A*0201-restricted T-cell epitopes of Mycobacterium tuberculosis

Vaccine ◽

10.1016/j.vaccine.2003.09.044 ◽

2004 ◽

Vol 22 (13-14) ◽

pp. 1609-1615 ◽

Cited By ~ 131

Author(s):

Maytal Bivas-Benita ◽

Krista E. van Meijgaarden ◽

Kees L.M.C. Franken ◽

Hans E. Junginger ◽

Gerrit Borchard ◽

...

Keyword(s):

Mycobacterium Tuberculosis ◽

T Cell ◽

Dna Vaccine ◽

Pulmonary Delivery ◽

T Cell Epitopes ◽

Dna Nanoparticles

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Vaccine-Elicited 10-Kilodalton Culture Filtrate Protein-Specific CD8+ T Cells Are Sufficient To Mediate Protection against Mycobacterium tuberculosis Infection

Infection and Immunity ◽

10.1128/iai.00024-08 ◽

2008 ◽

Vol 76 (5) ◽

pp. 2249-2255 ◽

Cited By ~ 39

Author(s):

Ying Wu ◽

Joshua S. Woodworth ◽

Daniel S. Shin ◽

Sheldon Morris ◽

Samuel M. Behar

Keyword(s):

T Cells ◽

Mycobacterium Tuberculosis ◽

Culture Filtrate ◽

Protective Immunity ◽

Protective Antigen ◽

T Cell Response ◽

Rapid Expansion ◽

Mycobacterium Tuberculosis Infection ◽

Infected People ◽

Culture Filtrate Protein

ABSTRACT The 10-kDa culture filtrate protein (CFP-10) and 6-kDa early secretory antigen of T cells (ESAT-6) are secreted in abundance by Mycobacterium tuberculosis and are frequently recognized by T cells from infected people. The genes encoding these proteins have been deleted from the genome of the vaccine strain Mycobacterium bovis bacillus Calmette-Guérin (BCG), and it is hypothesized that these proteins are important targets of protective immunity. Indeed, vaccination with ESAT-6 elicits protective CD4+ T cells in C57BL/6 mice. We have previously shown that M. tuberculosis infection of C3H mice elicits CFP-10-specific CD8+ and CD4+ T cells. Here we demonstrate that immunization with a CFP-10 DNA vaccine stimulates a specific T-cell response only to the H-2Kk-restricted epitope CFP-1032-39. These CFP-1032-39-specific CD8+ cells undergo a rapid expansion and accumulate in the lung following challenge of immunized mice with aerosolized M. tuberculosis. Protective immunity is induced by CFP-10 DNA vaccination as measured by a CFU reduction in the lung and spleen 4 and 8 weeks after challenge with M. tuberculosis. These data demonstrate that CFP-10 is a protective antigen and that CFP-1032-39-specific CD8+ T cells elicited by vaccination are sufficient to mediate protection against tuberculosis.

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A Novel Tuberculosis DNA Vaccine in an HIV-1 p24 Protein Backbone Confers Protection against Mycobacterium tuberculosis and Simultaneously Elicits Robust Humoral and Cellular Responses to HIV-1

Clinical and Vaccine Immunology ◽

10.1128/cvi.05700-11 ◽

2012 ◽

Vol 19 (5) ◽

pp. 723-730 ◽

Cited By ~ 4

Author(s):

Xiaoman Li ◽

Wei Xu ◽

Sidong Xiong

Keyword(s):

Mycobacterium Tuberculosis ◽

T Cell ◽

Dna Vaccine ◽

Cellular Response ◽

Mycobacterial Infection ◽

T Cell Epitopes ◽

Content Type ◽

P24 Protein ◽

Elevated Frequency ◽

Hiv 1

ABSTRACTTuberculosis (TB) caused byMycobacterium tuberculosisremains a major infectious disease worldwide. Moreover, latentM. tuberculosisinfection is more likely to progress to active TB and eventually leads to death when HIV infection is involved. Thus, it is urgent to develop a novel TB vaccine with immunogenicity to bothM. tuberculosisand HIV. In this study, four uncharacterized T cell epitopes from MPT64, Ag85A, Ag85B, and TB10.4 antigens ofM. tuberculosiswere predicted, and HIV-1-derived p24, an immunodominant protein that can induce protective responses to HIV-1, was used as an immunogenic backbone.M. tuberculosisepitopes were incorporated separately into the gene backbone of p24, forming a pP24-Mtb DNA vaccine. We demonstrated that pP24-Mtb immunization induced a strongM. tuberculosis-specific cellular response as evidenced by T cell proliferation, cytotoxicity, and elevated frequency of gamma interferon (IFN-γ)-secreting T cells. Interestingly, a p24-specific cellular response and high levels of p24-specific IgG were also induced by pP24-Mtb immunization. When the protective effect was assessed after mycobacterial challenge, pP24-Mtb vaccination significantly reduced tissue bacterial loads and profoundly attenuated the mycobacterial infection-related lung inflammation and injury. Our findings demonstrated that the pP24-Mtb tuberculosis vaccine confers effective protection against mycobacterial challenge with simultaneously elicited robust immune responses to HIV-1, which may provide clues for developing novel vaccines to prevent dual infections.

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Protective Vaccine Efficacy of the Complete Form of PPE39 Protein from Mycobacterium tuberculosis Beijing/K Strain in Mice

Clinical and Vaccine Immunology ◽

10.1128/cvi.00219-17 ◽

2017 ◽

Vol 24 (11) ◽

Cited By ~ 4

Author(s):

Ahreum Kim ◽

Yun-Gyoung Hur ◽

Sunwha Gu ◽

Sang-Nae Cho

Keyword(s):

T Cells ◽

Mycobacterium Tuberculosis ◽

T Cell ◽

Vaccine Development ◽

Protective Efficacy ◽

Interleukin 2 ◽

T Cell Epitopes ◽

Content Type ◽

Complete Form ◽

Ifn Γ

ABSTRACT The aim of this study was to evaluate the protective efficacy of MTBK_24820, a complete form of PPE39 protein derived from a predominant Beijing/K strain of Mycobacterium tuberculosis in South Korea. Mice were immunized with MTKB_24820, M. bovis Bacilli Calmette-Guérin (BCG), or adjuvant prior to a high-dosed Beijing/K strain aerosol infection. After 4 and 9 weeks, bacterial loads were determined and histopathologic and immunologic features in the lungs and spleens of the M. tuberculosis-infected mice were analyzed. Putative immunogenic T-cell epitopes were examined using synthetic overlapping peptides. Successful immunization of MTBK_24820 in mice was confirmed by increased IgG responses (P < 0.05) and recalled gamma interferon (IFN-γ), interleukin-2 (IL-2), IL-6, and IL-17 responses (P < 0.05 or P < 0.01) to MTBK_24820. After challenge with the Beijing/K strain, an approximately 0.5 to 1.0 log10 reduction in CFU in lungs and fewer lung inflammation lesions were observed in MTBK_24820-immunized mice compared to those for control mice. Moreover, MTBK_24820 immunization elicited significantly higher numbers of CD4+ T cells producing protective cytokines, such as IFN-γ and IL-17, in lungs and spleens (P < 0.01) and CD4+ multifunctional T cells producing IFN-γ, tumor necrosis factor alpha (TNF-α), and/or IL-17 (P < 0.01) than in control mice, suggesting protection comparable to that of BCG against the hypervirulent Beijing/K strain. The dominant immunogenic T-cell epitopes that induced IFN-γ production were at the N terminus (amino acids 85 to 102 and 217 to 234). Its vaccine potential, along with protective immune responses in vivo, may be informative for vaccine development, particularly in regions where the M. tuberculosis Beijing/K-strain is frequently isolated from TB patients.

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Mapping of V beta 11+ helper T cell epitopes on mycobacterial antigen in mouse primed with Mycobacterium tuberculosis

International Immunology ◽

10.1093/intimm/9.2.227 ◽

1997 ◽

Vol 9 (2) ◽

pp. 227-237 ◽

Cited By ~ 32

Author(s):

S Yanagisawa

Keyword(s):

Mycobacterium Tuberculosis ◽

T Cell ◽

Mycobacterial Antigen ◽

T Cell Epitopes ◽

Helper T Cell

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Sequence Diversity in the pe_pgrs Genes of Mycobacterium tuberculosis Is Independent of Human T Cell Recognition

mBio ◽

10.1128/mbio.00960-13 ◽

2014 ◽

Vol 5 (1) ◽

Cited By ~ 60

Author(s):

Richard Copin ◽

Mireia Coscollá ◽

Salome N. Seiffert ◽

Graham Bothamley ◽

Jayne Sutherland ◽

...

Keyword(s):

Mycobacterium Tuberculosis ◽

T Cell ◽

Sequence Variation ◽

Large Family ◽

Sequence Diversity ◽

Cell Recognition ◽

T Cell Epitopes ◽

Content Type ◽

T Cell Recognition ◽

Human T Cell

ABSTRACTTheMycobacterium tuberculosisgenome includes the large family ofpe_pgrsgenes, whose functions are unknown. Because of precedents in other pathogens in which gene families showing high sequence variation are involved in antigenic variation, a similar role has been proposed for thepe_pgrsgenes. However, the impact of immune selection onpe_pgrsgenes has not been examined. Here, we sequenced 27pe_pgrsgenes in 94 clinical strains from five phylogenetic lineages of theM. tuberculosiscomplex (MTBC). We found thatpe_pgrsgenes were overall more diverse than the remainder of the MTBC genome, but individual members of the family varied widely in their nucleotide diversity and insertion/deletion (indel) content: some were more, and others were much less, diverse than the genome average. Individualpe_pgrsgenes also differed in the ratio of nonsynonymous to synonymous mutations, suggesting that different selection pressures act on individualpe_pgrsgenes. Using bioinformatic methods, we tested whether sequence diversity inpe_pgrsgenes might be selected by human T cell recognition, the major mechanism of adaptive immunity to MTBC. We found that the large majority of predicted human T cell epitopes were confined to the conserved PE domain and experimentally confirmed the antigenicity of this domain in tuberculosis patients. In contrast, despite being genetically diverse, the PGRS domains harbored few predicted T cell epitopes. These results indicate that human T cell recognition is not a significant force driving sequence diversity inpe_pgrsgenes, which is consistent with the previously reported conservation of human T cell epitopes in the MTBC.IMPORTANCERecognition ofMycobacterium tuberculosisantigens by T lymphocytes is known to be important for immune protection against tuberculosis, but it is unclear whether human T cell recognition drives antigenic variation inM. tuberculosis. We previously discovered that the known human T cell epitopes in theM. tuberculosiscomplex are highly conserved, but we hypothesized that undiscovered epitopes with naturally occurring sequence variants might exist. To test this hypothesis, we examined thepe_pgrsgenes, a large family of genes that has been proposed to function in immune evasion byM. tuberculosis. We found that thepe_pgrsgenes exhibit considerable sequence variation, but the regions containing T cell epitopes and the regions of variation are distinct. These findings confirm that the majority of human T cell epitopes ofM. tuberculosisare highly conserved and indicate that selection forces other than T cell recognition drive sequence variation in thepe_pgrsgenes.

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