scholarly journals Peptides Derived fromMycobacterium lepraeML1601c Discriminate between Leprosy Patients and Healthy Endemic Controls

2012 ◽  
Vol 2012 ◽  
pp. 1-11 ◽  
Author(s):  
Kidist Bobosha ◽  
Jolien J. van der Ploeg-van Schip ◽  
Danuza A. Esquenazi ◽  
Marjorie M. Guimarães ◽  
Marcia V. Martins ◽  
...  
Keyword(s):  
Whole Blood ◽  
Early Stage ◽  
Mycobacterium Leprae ◽  
Diagnostic Tools ◽  
Whole Blood Assay ◽  
Cell Responses ◽  
Household Contacts ◽  
Blood Assay ◽  
Diagnostic Potential ◽  
Leprosy Patients

The stable incidence of new leprosy cases suggests that transmission of infection continues despite worldwide implementation of MDT. Thus, specific tools are needed to diagnose early stageMycobacterium lepraeinfection, the likely sources of transmission.M. lepraeantigens that induce T-cell responses inM. lepraeexposed and/or infected individuals thus are major targets for new diagnostic tools. Previously, we showed that ML1601c was immunogenic in patients and healthy household contacts (HHC). However, some endemic controls (EC) also recognized this protein. To improve the diagnostic potential, IFN-γresponses to ML1601c peptides were assessed using PBMC from Brazilian leprosy patients and EC. Five ML1601c peptides only induced IFN-γin patients and HHC. Moreover, 24-hour whole-blood assay (WBA), two ML1601c peptides could assess the level ofM. lepraeexposure in Ethiopian EC. Beside IFN-γ, also IP-10, IL-6, IL-1β, TNF-α, and MCP-1 were increased in EC from areas with high leprosy prevalence in response to these ML1601c peptides. Thus, ML1601c peptides may be useful for differentiatingM. lepraeexposed or infected individuals and can also be used to indicate the magnitude ofM. lepraetransmission even in the context of various HLA alleles as present in these different genetic backgrounds.

scholarly journals Rational Combination of Peptides Derived from Different Mycobacterium leprae Proteins Improves Sensitivity for Immunodiagnosis of M. leprae Infection

2008 ◽  
Vol 15 (3) ◽  
pp. 522-533 ◽  
Author(s):  
Annemieke Geluk ◽  
Jolien van der Ploeg ◽  
Rose O. B. Teles ◽  
Kees L. M. C. Franken ◽  
Corine Prins ◽  
...  
Keyword(s):  
T Cell ◽  
Early Stage ◽  
T Cell Responses ◽  
Hla Class I ◽  
Mycobacterium Leprae ◽  
Diagnostic Tools ◽  
Cell Responses ◽  
Diagnostic Potential ◽  
Leprosy Patients ◽  
Hla Binding

ABSTRACT The stable incidence of new leprosy cases suggests that transmission of infection is continuing despite the worldwide implementation of multidrug therapy programs. Highly specific tools are required to accurately diagnose asymptomatic and early stage Mycobacterium leprae infections which are the likely sources of transmission and cannot be identified by using the detection of antibodies against phenolic glycolipid I. One of the hurdles hampering T-cell-based diagnostic tests is that M. leprae antigens cross-react at the T-cell level with antigens present in other mycobacteria, like M. tuberculosis or M. bovis bacillus Calmette-Guerin (BCG). Using comparative genomics, we previously identified five candidate proteins highly restricted to M. leprae which showed promising features with respect to application in leprosy diagnostics. However, despite the lack of overall sequence homology, the use of recombinant proteins includes the risk of detecting T-cell responses that are cross-reactive with other antigens. To improve the diagnostic potential of these M. leprae sequences, we used 50 synthetic peptides spanning the sequences of all five proteins for the induction of T-cell responses (gamma interferon) in leprosy patients, healthy household contacts (HHC) of leprosy patients, and healthy controls in Brazil, as well as in tuberculosis patients, BCG vaccinees, and healthy subjects from an area of nonendemicity. Using the combined T-cell responses toward four of these peptides, all paucibacillary patients and 13 out of 14 HHC were detected without compromising specificity. The peptides contain HLA binding motifs for various HLA class I and II alleles, thereby meeting an important requirement for the applicability of diagnostic tools in genetically diverse populations. Thus, this study provides the first evidence for the possibility of immunodiagnostics for leprosy based on mixtures of peptides recognized in the context of different HLA alleles.

scholarly journals From Genome-Based In Silico Predictions to Ex Vivo Verification of Leprosy Diagnosis

2009 ◽  
Vol 16 (3) ◽  
pp. 352-359 ◽  
Author(s):  
Annemieke Geluk ◽  
John S. Spencer ◽  
Kidist Bobosha ◽  
Maria C. V. Pessolani ◽  
Geraldo M. B. Pereira ◽  
...  
Keyword(s):  
T Cell ◽  
Mononuclear Cells ◽  
T Cell Responses ◽  
Immunoglobulin M ◽  
Diagnostic Tools ◽  
Cell Responses ◽  
Household Contacts ◽  
Diagnostic Potential ◽  
Human T Cell ◽  
Leprosy Patients

ABSTRACT The detection of hundreds of thousands of new cases of leprosy every year suggests that transmission of Mycobacterium leprae infection still continues. Unfortunately, tools for identification of asymptomatic disease and/or early-stage M. leprae infection (likely sources of transmission) are lacking. The recent identification of M. leprae-unique genes has allowed the analysis of human T-cell responses to novel M. leprae antigens. Antigens with the most-promising diagnostic potential were tested for their ability to induce cytokine secretion by using peripheral blood mononuclear cells from leprosy patients and controls in five different areas where leprosy is endemic; 246 individuals from Brazil, Nepal, Bangladesh, Pakistan, and Ethiopia were analyzed for gamma interferon responses to five recombinant proteins (ML1989, ML1990, ML2283, ML2346, and ML2567) and 22 synthetic peptides. Of these, the M. leprae-unique protein ML1989 was the most frequently recognized and ML2283 the most specific for M. leprae infection/exposure, as only a limited number of tuberculosis patients responded to this antigen. However, all proteins were recognized by a significant number of controls in areas of endemicity. T-cell responses correlated with in vitro response to M. leprae, suggesting that healthy controls in areas where leprosy is endemic are exposed to M. leprae. Importantly, 50% of the healthy household contacts and 59% of the controls in areas of endemicity had no detectable immunoglobulin M antibodies to M. leprae-specific PGL-I but responded in T-cell assays to ≥1 M. leprae protein. T-cell responses specific for leprosy patients and healthy household contacts were observed for ML2283- and ML0126-derived peptides, indicating that M. leprae peptides hold potential as diagnostic tools. Future work should concentrate on the development of a sensitive and field-friendly assay and identification of additional peptides and proteins that can induce M. leprae-specific T-cell responses.

Antigen-specific secretion of IFNγ and CXCL10 in whole blood assay detects Mycobacterium leprae infection but does not discriminate asymptomatic infection from symptomatic leprosy

2017 ◽  
Vol 87 (4) ◽  
pp. 328-334 ◽  
Author(s):  
Emerith Mayra Hungria ◽  
Aline Araújo Freitas ◽  
Maria Araci Andrade Pontes ◽  
Heitor Sá Gonçalves ◽  
Ana Lúcia Osório Maroccolo Sousa ◽  
...  
Keyword(s):  
Whole Blood ◽  
Mycobacterium Leprae ◽  
Asymptomatic Infection ◽  
Whole Blood Assay ◽  
Blood Assay

scholarly journals Uncovering Distinct Primary Vaccination-Dependent Profiles in Human Bordetella pertussis Specific CD4+ T-Cell Responses Using a Novel Whole Blood Assay

Vaccines ◽  
2020 ◽  
Vol 8 (2) ◽  
pp. 225
Author(s):  
Eleonora E. Lambert ◽  
Véronique Corbière ◽  
Jacqueline A. M. van Gaans-van den Brink ◽  
Maxime Duijst ◽  
Prashanna Balaji Venkatasubramanian ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Bordetella Pertussis ◽  
Whole Blood ◽  
T Cell Responses ◽  
Primary Vaccination ◽  
Cd4 T Cell ◽  
Whole Blood Assay ◽  
Cell Responses ◽  
Blood Assay

To advance research and development of improved pertussis vaccines, new immunoassays are needed to qualify the outcome of Bordetella pertussis (Bp) specific CD4+ T-cell differentiation. Here, we applied a recently developed whole blood assay to evaluate Bp specific CD4+ T-cell responses. The assay is based on intracellular cytokine detection after overnight in vitro Bp antigen stimulation of diluted whole blood. We show for the first time that CD4+ T-cell memory of Th1, Th2, and Th17 lineages can be identified simultaneously in whole blood. Participants ranging from 7 to 70 years of age with different priming backgrounds of whole-cell pertussis (wP) and acellular pertussis (aP) vaccination were analyzed around an acellular booster vaccination. The assay allowed detection of low frequent antigen-specific CD4+ T-cells and revealed significantly elevated numbers of activated and cytokine-producing CD4+ T-cells, with a significant tendency to segregate recall responses based on primary vaccination background. A stronger Th2 response hallmarked an aP primed cohort compared to a wP primed cohort. In conclusion, analysis of Bp specific CD4+ T-cell responses in whole blood showed separation based on vaccination background and provides a promising tool to assess the quantity and quality of CD4+ T-cell responses induced by vaccine candidates.

scholarly journals Rapid, simplified whole blood-based multiparameter assay to quantify and phenotype SARS-CoV-2 specific T cells

2020 ◽  
Author(s):  
Catherine Riou ◽  
Georgia Schäfer ◽  
Elsa du Bruyn ◽  
Rene T. Goliath ◽  
Cari Stek ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Whole Blood ◽  
T Cell Responses ◽  
Cd4 T Cell ◽  
Proof Of Concept ◽  
Whole Blood Assay ◽  
Cell Responses ◽  
Vaccine Trials ◽  
Blood Assay

ABSTRACTRapid tests to evaluate SARS-CoV-2-specific T cell responses are urgently needed to decipher protective immunity and aid monitoring vaccine-induced immunity. Using a rapid whole blood assay requiring minimal amount of blood, we measured qualitatively and quantitatively SARS-CoV-2-specific CD4 T cell responses in 31 healthcare workers, using flow cytometry. 100% of COVID-19 convalescent participants displayed a detectable SARS-CoV-2-specific CD4 T cell response. SARS-CoV-2-responding cells were also detected in 40.9% of participants with no COVID-19-associated symptoms or who tested PCR negative. Phenotypic assessment indicated that, in COVID-19 convalescent participants, SARS-CoV-2 CD4 responses displayed an early differentiated memory phenotype with limited capacity to produce IFNγ. Conversely, in participants with no reported symptoms, SARS-CoV-2 CD4 responses were enriched in late differentiated cells, co-expressing IFNγ and TNFα and also Granzyme B. This proof of concept study presents a scalable alternative to PBMC-based assays to enumerate and phenotype SARS-CoV-2-responding T cells, thus representing a practical tool to monitor adaptive immunity in vaccine trials.SummaryIn this proof of concept study, we show that SARS-CoV-2 T cell responses are easily detectable using a rapid whole blood assay requiring minimal blood volume. Such assay could represent a suitable tool to monitor adaptive immunity in vaccine trials.

scholarly journals A High Throughput Whole Blood Assay for Analysis of Multiple Antigen-Specific T Cell Responses in HumanMycobacterium tuberculosisInfection

2018 ◽  
Vol 200 (8) ◽  
pp. 3008-3019 ◽  
Author(s):  
Wendy E. Whatney ◽  
Neel R. Gandhi ◽  
Cecilia S. Lindestam Arlehamn ◽  
Azhar Nizam ◽  
Hao Wu ◽  
...  
Keyword(s):  
T Cell ◽  
High Throughput ◽  
Whole Blood ◽  
T Cell Responses ◽  
Whole Blood Assay ◽  
Cell Responses ◽  
Blood Assay ◽  
Multiple Antigen
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