scholarly journals Screening for Mycobacterium tuberculosis Infection Using Beijing/K Strain-Specific Peptides in a School Outbreak Cohort

Author(s):  
Ji Young Hong ◽  
Ahreum Kim ◽  
So Yeong Park ◽  
Sang-Nae Cho ◽  
Hazel M. Dockrell ◽  
...  

BackgroundThe Beijing strain of Mycobacterium tuberculosis (M. tb) has been most frequently isolated from TB patients in South Korea, and the hyper-virulent Beijing/K genotype is associated with TB outbreaks. To examine the diagnostic potential of Beijing/K-specific peptides, we performed IFN-γ release assays (IGRA) using a MTBK antigen tube containing Beijing/K MTBK_24800, ESAT-6, and CFP-10 peptides in a cohort studied during a school TB outbreak.MethodsA total of 758 contacts were investigated for M. tb infection, and 43 contacts with latent TB infection (LTBI) and 25 active TB patients were enrolled based on serial screening with QuantiFERON-TB Gold In-Tube tests followed by clinical examinations. Blood collected in MTBK antigen tubes was utilized for IGRA and multiplex cytokine bead arrays. Immune responses were retested in 24 patients after TB treatment, and disease progression was investigated in subjects with LTBI.ResultsTotal proportions of active disease and LTBI during the outbreak were 3.7% (28/758) and 9.2% (70/758), respectively. All clinical isolates had a Beijing/K M. tb genotype. IFN-γ responses to the MTBK antigen identified M. tb infection and distinguished between active disease and LTBI. After anti-TB treatment, IFN-γ responses to the MTBK antigen were significantly reduced, and strong TNF-α responses at diagnosis were dramatically decreased.ConclusionsMTBK antigen-specific IFN-γ has diagnostic potential for differentiating M. tb infection from healthy controls, and between active TB and LTBI as well. In addition, TNF-α is a promising marker for monitoring therapeutic responses. These data provide informative readouts for TB diagnostics and vaccine studies in regions where the Beijing/K strain is endemic.

2020 ◽  
Vol 58 (6) ◽  
Author(s):  
Danilo Buonsenso ◽  
Giovanni Delogu ◽  
Clelia Perricone ◽  
Roberta Grossi ◽  
Angela Careddu ◽  
...  

ABSTRACT Compared to its predecessor QuantiFERON-TB Gold In Tube (QFT-IT), QuantiFERON-TB Gold Plus (QFT-Plus) contains an additional antigen tube (TB2), stimulating both CD4+ and CD8+ T cells. The ability to discriminate CD4+ and CD8+ responses is suggested to be useful in differentiating stages of Mycobacterium tuberculosis infection. While QFT-Plus has already been evaluated in adults, there are not enough data in children evaluated for suspected active tuberculosis (TB) or latent TB infection (LTBI). A prospective cross-sectional study was conducted among children aged 0 to 17 years who were evaluated for suspected active TB or screened for LTBI. All children underwent QFT-Plus and further clinical, radiological, and/or microbiological analyses according to clinical scenario. Of the 198 children enrolled, 43 (21.7%) were tested because of suspicion of active TB. A total of 12/43 (27.9%) were diagnosed with active TB, and among these, 10/12 (83.3%) had a positive QFT-Plus assay. Of the 155 children screened for LTBI, 18 (11.6%) had a positive QFT-Plus, and 5 (2.5%) had an indeterminate result. TB1 and TB2 quantitative responses were not able to discriminate active disease from latent infection. The percent agreement between TB1 and TB2 was 100%. QFT-Plus assay showed good sensitivity for active TB and was particularly useful for the evaluation of children with suspected LTBI, giving a low rate of indeterminate results in this group. More studies are needed to properly evaluate QFT-Plus ability in discriminating active disease from latent infection.


2009 ◽  
Vol 36 (9) ◽  
pp. 1876-1884 ◽  
Author(s):  
BOLETTE SOBORG ◽  
MORTEN RUHWALD ◽  
MERETE LUND HETLAND ◽  
SØREN JACOBSEN ◽  
AASE BENGAARD ANDERSEN ◽  
...  

Objective.To test if Mycobacterium tuberculosis screening results differ among patients with inflammatory disease depending on whether the QuantiFeron TB-Gold test (QFT) or tuberculin skin test (TST) is used; and to evaluate if a possible difference is influenced by the presence of risk factors or immunosuppression.Methods.The interferon-γ response to in vitro stimulation of M. tuberculosis-specific antigens was measured with QFT and results were compared with TST. Associations to bacillus Calmette-Guerin (BCG) vaccination, risk factors, and immunosuppression were analyzed for both tests.Results.QFT and TST results were available for 294/302 and 241/302 patients, respectively; 234 had results from both tests. Twenty-one (7%) tested positive with QFT and 45 (19%) with TST. A positive QFT was associated with risk factors for M. tuberculosis infection: i.e., birth or upbringing in a TB-endemic area [risk ratio (RR) = 7.8, 95% CI 1.5–18.2, p < 0.001], previous TB treatment (RR 4.7, 95% CI 1.6–13.5, p = 0.005), and any latent TB infection risk factor (RR 4.7, 95% CI 2.1–11.0, p = 0.0002). Treatment with corticosteroids increased the risk for an inconclusive QFT result (RR 4.2, 95% CI 1.6–10.7, p = 0.04) and decreased the risk for a positive TST result (RR 0.4, 95% CI 0.1–1.0, p = 0.04). Agreement between the tests was low (kappa 0.2, 95% CI 0.02–0.3, p = 0.002).Conclusion.The study documented a high degree of discordant positive QFT and TST results. A positive QFT was more closely associated with risk factors for M. tuberculosis infection than the TST. The use of corticosteroids affected test outcome by increasing the risk for an inconclusive QFT result and decreasing the risk for a positive TST result.


2021 ◽  
Vol 27 (1) ◽  
Author(s):  
Rasoul Mirzaei ◽  
Sajad Babakhani ◽  
Parisa Ajorloo ◽  
Razieh Heidari Ahmadi ◽  
Seyed Reza Hosseini-Fard ◽  
...  

AbstractTuberculosis (TB), caused by Mycobacterium tuberculosis (Mtb), has been the world’s driving fatal bacterial contagious disease globally. It continues a public health emergency, and around one-third of the global community has been affected by latent TB infection (LTBI). This is mostly due to the difficulty in diagnosing and treating patients with TB and LTBI. Exosomes are nanovesicles (40–100 nm) released from different cell types, containing proteins, lipids, mRNA, and miRNA, and they allow the transfer of one’s cargo to other cells. The functional and diagnostic potential of exosomal miRNAs has been demonstrated in bacterial infections, including TB. Besides, it has been recognized that cells infected by intracellular pathogens such as Mtb can be secreting an exosome, which is implicated in the infection’s fate. Exosomes, therefore, open a unique viewpoint on the investigative process of TB pathogenicity. This study explores the possible function of exosomal miRNAs as a diagnostic biomarker. Moreover, we include the latest data on the pathogenic and therapeutic role of exosomal miRNAs in TB.


Pathogens ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 517
Author(s):  
Magdalena Druszczynska ◽  
Michal Seweryn ◽  
Sebastian Wawrocki ◽  
Magdalena Kowalewska-Pietrzak ◽  
Anna Pankowska ◽  
...  

None of the currently used diagnostic tools are efficient enough in diagnosing Mycobacterium tuberculosis (M.tb) infection in children. The study was aimed to identify cytokine biosignatures characterizing active and latent tuberculosis (TB) in children. Using a multiplex bead-based technology, we analyzed the levels of 53 Th17-related cytokines and inflammatory mediators in sera from 216 BCG-vaccinated children diagnosed with active TB (TB) or latent TB (LTBI) as well as uninfected controls (HC). Children with active TB, compared to HC children, showed reduced serum levels of IL-17A, MMP-2, OPN, PTX-3, and markedly elevated concentrations of APRIL/TNFSF13. IL-21, sCD40L, MMP-2, and IL-8 were significantly differentially expressed in the comparisons between groups: (1) HC versus TB and LTBI (jointly), and (2) TB versus LTBI. The panel consisting of APRIL/TNFSF13, sCD30/TNFRSF8, IFN-α2, IFN-γ, IL-2, sIL-6Rα, IL-8, IL-11, IL-29/IFN-λ1, LIGHT/TNFSF14, MMP-1, MMP-2, MMP-3, osteocalcin, osteopontin, TSLP, and TWEAK/TNFSF12 possessed a discriminatory potential for the differentiation between TB and LTBI children. Serum-based host biosignatures carry the potential to aid the diagnosis of childhood M.tb infections. The proposed panels of markers allow distinguishing not only children infected with M.tb from uninfected individuals but also children with active TB from those with latent TB.


2010 ◽  
Vol 17 (12) ◽  
pp. 1985-1990 ◽  
Author(s):  
Shu Zhang ◽  
Lingyun Shao ◽  
Ling Mo ◽  
Jiazhen Chen ◽  
Feifei Wang ◽  
...  

ABSTRACT T-cell-based gamma interferon (IFN-γ) release assays (IGRAs) using Mycobacterium tuberculosis-specific antigens have shown higher sensitivity and specificity than the routine tuberculin skin test (TST). However, the effects of Mycobacterium bovis BCG vaccination and anti-tuberculosis (TB) treatment on dynamic T-cell responses to M. tuberculosis-specific antigens in active TB cases have rarely been investigated in regions where TB is endemic. Eighty-nine patients with active pulmonary TB (ATB) and 57 healthy controls (HC) from China were recruited and tested by sputum smear and culture, TSTs, and IGRAs with M. tuberculosis-specific antigens ESAT-6 and CFP-10 (T-SPOT.TB) as well as purified protein derivative (PPD) stimulation. All 146 participants were screened by the T-SPOT.TB assay at recruitment. T-SPOT.TB-positive rates in ATB and HC groups were 87.6% (78/89) and 21.1% (12/57), respectively. Of 38 ATB patients who were both TST and T-SPOT.TB tested, the positive rates were 73.7% (28/38) and 94.7% (36/38), respectively (P = 0.0215), and those in the HC group were 62.3% (33/53) and 18.9% (10/53), respectively (P < 0.0001). The T-SPOT.TB-positive rates declined during TB treatment and were 94.4% (51/54), 86.4% (19/22), and 61.5% (8/13) for ATB patients receiving 0- to 1-month, 1- to 3-month, and 3- to 6-month anti-TB treatment, respectively. The IGRA is a most promising test for both active TB and latent TB infection (LTBI) diagnosis due to the improvement of its specificity and convenience, especially in the Mycobacterium bovis BCG-vaccinated population. Furthermore, the T-SPOT.TB assay using ESAT-6 and CFP-10 in ATB patients during anti-TB treatment could serve as a potential predictor of therapeutic efficacy.


2018 ◽  
Author(s):  
Mrinal K. Das ◽  
Aurelie A. Ray ◽  
Yi Cai ◽  
Akul Singhania ◽  
Christine M. Graham ◽  
...  

AbstractExperimental mouse models of TB suggest that early events in the lung impact immunity. Early events in the human lung in response to TB are difficult to probe and their impact on disease outcome is unknown. We have shown in mouse that a secreted alternatively-spliced variant of IL-12Rβ1, lacking the transmembrane domain and termed ΔTM-IL-12Rβ1, promotes dendritic cell migration to the draining lymph node, augments T cell activation and limits dissemination ofM. tuberculosis(Mtb). We show here that CBA/J and C3H/HeJ mice (both highly susceptible to Mtb) express higher levels of ΔTM-IL-12Rβ1 than resistant C57BL6 mice and limit early dissemination of Mtb from the lungs. Both CD11c+ cells and T cells express ΔTM-IL-12Rβ1 in humans, and mice unable to make ΔTM-IL-12Rβ1 in either CD4 or CD11c expressing cells permit early dissemination from the lung. Analysis of publically available blood transcriptomes indicates that pulmonary TB is associated with high ΔTM-IL-12Rβ1 expression and that of all IL-12 related signals, the ΔTM-IL-12Rβ1 signal best predicts active disease. ΔTM-IL-12Rβ1 expression reflects the heterogeneity of latent TB infection and has the capacity to discriminate between latent and active disease. In a new Chinese TB patient cohort, ΔTM-IL-12Rβ1 effectively differentiates TB from latent TB, healthy controls and pneumonia patients. Finally, ΔTM-IL-12Rβ1 expression drops in drug-treated individuals in the UK and China where infection pressure is low. We propose that ΔTM-IL-12Rβ1 regulates early dissemination from the lung and that it has diagnostic potential and provides mechanistic insights into human TB.


2020 ◽  
pp. 4026-4031
Author(s):  
Hannah Jarvis ◽  
Onn Min Kon

Mycobacteria are Gram-negative, rod-shaped bacilli comprising the Mycobacterium tuberculosis complex (TB) and non-tuberculous mycobacteria. Infection, usually via inhalation, is often asymptomatic but can lead to primary TB or to latent TB infection which can later develop into ‘reactivation’ or ‘post-primary’ active disease. Pulmonary TB is the commonest manifestation, but extrapulmonary disease can affect almost any organ. Definitive diagnosis is by culture. Standard chemotherapy involves the use of rifampicin, isoniazid, pyrazinamide, and ethambutol. Drug resistance is an increasing problem. Around 1.5 million people die from TB each year. Infection tends to present with a worsening of chronic respiratory symptoms in patients with underlying lung diseases. Diagnosis is difficult because these organisms are common in the environment. A long course of treatment with several drugs is required.


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