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The eradication of tuberculosis remains a global challenge. Despite being the only licensed vaccine, Bacillus Calmette-Guérin (BCG) confers limited protective efficacy in adults and individuals with latent tuberculosis infections (LTBI). There is an urgent need to develop novel vaccines that can enhance the protective effect of BCG. Protein subunit vaccines have garnered significant research interest due to their safety and plasticity. Based on previous studies, we selected three antigens associated with LTBI (Rv2028c, Rv2029c, Rv3126c) and fused them with an immunodominant antigen Ag85A, resulting in the construction of a multistage protein subunit vaccine named A986. We evaluated the protective effect of recombinant protein A986 adjuvanted with MPL/QS21 as a booster vaccine for BCG against Mycobacterium tuberculosis (Mtb) infection in mice. The A986 + MPL/QS21 induced the secretion of antigen-specific Th1 (IL-2 + , IFN-γ + and TNF-α + ) and Th17 (IL-17A + ) cytokines in CD4 + and CD8 + T cells within the lung and spleen of mice, while also increased the frequency of central memory and effector memory T cells. Additionally, it also induced the enhanced production of IgG antibodies. Compared to BCG alone, A986 + MPL/QS21 boosting significantly augmented the proliferation of antigen-specific multifunctional T cells and effectively reduced bacterial load in infected mice. Taken together, A986 + MPL/QS21 formulation induced robust antigen-specific immune responses and provided enhanced protection against Mtb infection as a booster of BCG vaccine., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Most people infected with Mycobacterium tuberculosis ( Mtb ) are believed to be in a state of latent tuberculosis (TB) infection (LTBI). Although LTBI is asymptomatic and not infectious, there is a risk of developing active disease even decades after infection. Here, to characterize mutations acquired during LTBI, we collected and analyzed Mtb genomes from seven Japanese patient pairs, each pair consisting of two active TB patients whose starting dates of developing active disease were >3 years apart; one had a high suspicion of LTBI before developing active disease, whereas the other did not. Thereafter, we compared these genomes with those of longitudinal sample pairs within a host of chronic active TB infections combined with public data. The bacterial populations in patients with LTBI were genetically more homogeneous and accumulated single nucleotide polymorphisms (SNPs) slower than those from active disease. Moreover, the lower proportion of nonsynonymous SNPs indicated weaker selective pressures during LTBI than active disease. Finally, the different mutation spectrums indicated different mutators between LTBI and active disease. These results suggest that the likelihood of the acquisition of mutations responsible for antibiotic resistance and increased virulence was lower in the Mtb population from LTBI than active disease.IMPORTANCEControlling latent tuberculosis (TB) infection (LTBI) activation is an effective strategy for TB elimination, where understanding Mycobacterium tuberculosis ( Mtb ) dynamics within the host plays an important role. Previous studies on chronic active disease reported that Mtb accumulated genomic mutations within the host, possibly resulting in acquired drug resistance and increased virulence. However, several reports suggest that fewer mutations accumulate during LTBI than during the active disease, but the associated risk is largely unknown. Here, we analyzed the genomic dynamics of Mtb within the host during LTBI. Our results statistically suggest that Mtb accumulates mutations during LTBI, but most mutations are under low selective pressures, which induce mutations responsible for drug resistance and virulence. Thus, we propose that LTBI acts as a source for new TB disease rather than as a period for in-host genome evolution., Competing Interests: The authors declare no conflict of interest.

One-quarter of the world's population is infected with Mycobacterium tuberculosis ( Mtb ). After initial exposure, more immune-competent persons develop asymptomatic latent tuberculosis infection (LTBI) but not active diseases, creates an extensive reservoir at risk of developing active tuberculosis. Previously, we constructed a novel recombinant Sendai virus (SeV)-vectored vaccine encoding two dominant antigens of Mtb , which elicited immune protection against acute Mtb infection. In this study, nine Mtb latency-associated antigens were screened as potential supplementary vaccine candidate antigens, and three antigens (Rv2029c, Rv2028c, and Rv3126c) were selected based on their immune-therapeutic effect in mice, and their elevated immune responses in LTBI human populations. Then, a recombinant SeV-vectored vaccine, termed SeV986A, that expresses three latency-associated antigens and Ag85A was constructed. In murine models, the doses, titers, and inoculation sites of SeV986A were optimized, and its immunogenicity in BCG-primed and BCG-naive mice were determined. Enhanced immune protection against the Mtb challenge was shown in both acute-infection and latent-infection murine models. The expression levels of several T-cell exhaustion markers were significantly lower in the SeV986A-vaccinated group, suggesting that the expression of latency-associated antigens inhibited the T-cell exhaustion process in LTBI infection. Hence, the multistage quarter-antigenic SeV986A vaccine holds considerable promise as a novel post-exposure prophylaxis vaccine against tuberculosis.

Objective: To understand the infection status of mycobacterium tuberculosis among health workers in tuberculosis designated medical institutions and explore the risk factors of infection. Methods: From September 2021 to June 2022, a questionnaire survey was conducted among health workers in relevant departments of 4 tuberculosis designated medical institutions by cluster stratified sampling, including the implementation of hospital infection control measures in medical institutions and occupational exposure of medical staff to mycobacterium tuberculosis. Peripheral blood interferon gamma release assays (IGRAs) and lung imaging examination were performed to determine the mycobacterium tuberculosis infection. Factors with statistical significance in univariate analysis were included in multivariate logistic regression to analyze the risk factors of mycobacterium tuberculosis infection. Results: A total of 657 people completed the lung imaging examination and questionnaire, of which 654 people had peripheral blood IGRAs detection, and the latent infection rate of tuberculosis was 39.45% (258/654) . Univariate analysis showed that age, sex, marital status, economic income, occupational category, professional title, length of service, and other variables had statistical significances in tuberculosis latent infection ( P <0.05) . In terms of personal health status, there were statistically significant differences in the distribution of health workers in terms of their tuberculosis history, tuberculosis history of their immediate family members, previous tuberculin skin test (TST) ( P <0.05) . Multivariate analysis showed that there were four risk factors related to tuberculosis, including professional title ( X (1)) , years of tuberculosis related works ( X (2)) , tuberculosis history ( X (3)) and previous TST ( X (4)) . The regression equation of the probability of tuberculosis among health workers was y =-1.920+0.246 X (1)+0.046 X (2)+1.231 X (3)+0.478 X (4). Conclusion: The latent infection rate of tuberculosis among health workers in tuberculosis designated medical institutions is high. It is necessary to strengthen the management of infection control, carry out regular screening, enhance the self-protection awareness of health workers, and reduce their exposure to mycobacterium tuberculosis and infection risk.

Background: Currently, diagnosis of latent TB infection (LTBI) is based on the secretion of IFN-γ in response to Mycobacterium tuberculosis (Mtb) antigens, the absence of which is regarded as no infection. Some individuals appear to resist Mtb infection despite sustained exposure (resisters). In this study, we aimed to assess cytokines, chemokines and antibodies that may be associated with resistance to Mtb infection. We hypothesized that there may be an alternative immune response to Mtb exposure in the absence of IFN-γ in resisters., Methods: We enrolled HIV-uninfected healthcare workers who had worked in high TB-exposure environments for 5 years or longer. We screened them for LTBI using the tuberculin skin test and the QuantiFERON-TB Gold Plus assay. We performed multiplex Luminex to measure concentrations of T cell-associated cytokines and chemokines as well as total antibodies in plasma collected from unstimulated fresh whole blood and supernatants from QuantiFERON-TB Gold Plus tubes following incubation of whole blood for 16-24 hours with ESAT6/CFP10 peptides., Results: Samples from 78 individuals were analyzed: 33 resisters (TST<10mm; IGRA<0.35 IU/mL), 33 with LTBI (TST≥10mm and IGRA≥0.35 IU/mL) and 12 discordant (TST=0mm; IGRA≥1.0 IU/mL). There were no differences in concentrations of cytokines and chemokines in plasma between the different groups. Resisters had significantly lower concentrations of IFN-γ, IL-2, TNF-α, MIP-1α, MIP-1β, ITAC, IL-13 and GM-CSF in supernatants compared with LTBI group. There were no significant differences in the concentrations in supernatants of IL-10, IL-1β, IL-17A, IL-21, IL-23, MIP-3α, IL-4, IL-5, IL-6, IL-7, IL-8, Fractalkine and IL-12p70 between the groups. We observed that resisters had similar concentrations of total antibodies (IgG1, IgG2, IgG3, IgG4, IgA, and IgM) in plasma and supernatants compared to the LTBI and discordant groups., Conclusion: Resistance to Mtb infection despite sustained exposure is associated with lower Mtb-specific secretion of Th1-associated cytokines and chemokines. However, resisters showed secreted concentrations after Mtb stimulation of total antibodies and cytokines/chemokines associated with innate and Th17 immune responses similar to those with Mtb infection. This suggests an ability to mount non-IFN-γ immune responses to Mtb in apparent resisters., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Shey, Balfour, Masina, Bekiswa, Schutz, Goliath, Dielle, Katoto, Wilkinson, Lewinsohn, Lewinsohn and Meintjes.)

Background: A mechanistic understanding of uncommon immune outcomes such as resistance to infection has led to the development of novel therapies. Using gene level analytic methods, we previously found distinct monocyte transcriptional responses associated with resistance to Mycobacterium tuberculosis (Mtb) infection defined as persistently negative tuberculin skin test (TST) and interferon gamma release assay (IGRA) reactivity among highly exposed contacts (RSTR phenotype)., Objective: Using transcript isoform analyses, we aimed to identify novel RSTR-associated genes hypothesizing that previous gene-level differential expression analysis obscures isoform-specific differences that contribute to phenotype., Materials and Methods: Monocytes from 49 RSTR versus 52 subjects with latent Mtb infection (LTBI) were infected with M. tuberculosis (H37Rv) or left unstimulated (media) prior to RNA isolation and sequencing. RSTR-associated gene expression was then identified using differential transcript isoform analysis., Results: We identified 81 differentially expressed transcripts (DETs) in 70 genes (FDR <0.05) comparing RSTR and LTBI phenotypes with the majority (n = 79 DETs) identified under Mtb-stimulated conditions. Seventeen of these genes were previously identified with gene-level bulk RNAseq analyses including genes in the IFNγ response that had increased expression among LTBI subjects, findings consistent with a clinical phenotype based on IGRA reactivity. Among the subset of 23 genes with positive differential expression among Mtb-infected RSTR monocytes, 13 were not previously identified. These novel DET genes included PDE4A and ZEB2, which each had multiple DETs with higher expression among RSTR subjects, and ACSL4 and GAPDH that each had a single transcript isoform associated with RSTR., Conclusion and Limitations: Transcript isoform-specific analyses identify transcriptional associations, such as those associated with resistance to TST/IGRA conversion, that are obscured when using gene-level approaches. These findings should be validated with additional RSTR cohorts and whether the newly identified candidate resistance genes directly influence the monocyte Mtb response requires functional study., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Simmons et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Mycobacterium tuberculosis infection outcomes have been described as active tuberculosis or latent infection but a spectrum of outcomes is now recognized. We used a nonhuman primate model, which recapitulates human infection, to characterize the clinical, microbiologic, and radiographic patterns associated with developing latent M. tuberculosis infection. Four patterns were identified. "Controllers" had normal erythrocyte sedimentation rate (ESR) without M. tuberculosis growth in bronchoalveolar lavage or gastric aspirate (BAL/GA). "Early subclinicals" showed transient ESR elevation and/or M. tuberculosis growth on BAL/GA for 60 days postinfection, "mid subclinicals" were positive for 90 days, and "late subclinicals" were positive intermittently, despite the absence of clinical disease. Variability was noted regarding granuloma formation, lung/lymph node metabolic activity, lung/lymph node bacterial burden, gross pathology, and extrapulmonary disease. Like human M. tuberculosis infection, this highlights the heterogeneity associated with the establishment of latent infection, underscoring the need to understand the clinical spectrum and risk factors associated with severe disease., Competing Interests: Potential conflicts of interest. All authors: No reported conflicts of interest. All authors have submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest. Conflicts that the editors consider relevant to the content of the manuscript have been disclosed., (© The Author(s) 2023. Published by Oxford University Press on behalf of Infectious Diseases Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Objectives: To evaluate the performance of selected host immunological biomarkers in differentiating tuberculosis (TB) disease from latent TB infection (LTBI) in HIV uninfected and infected individuals enrolled in TB low-burden countries., Design: Participants with TB disease (N = 85) and LTBI (N = 150) were recruited from prospective cohorts at hospitals in Norway and Denmark. Plasma concentrations of 54 host markers were assessed by Luminex multiplex immunoassays. Using receiver operator characteristic curves and general discriminant analysis, we determined the abilities of individual and combined biomarkers to discriminate between TB disease and LTBI including when patients were stratified according to HIV infection status., Results: Regardless of the groups compared, CCL1 and IL-2Ra were the most accurate single biomarkers in differentiating TB disease from LTBI. Regardless of HIV status, a 4-marker signature (CCL1+RANTES+CRP+MIP-1α) derived from a training set (n = 155) differentiated TB disease from LTBI in the test set (n = 67) with a sensitivity of 56.0% (95% CI, 34.9-75.6) and a specificity of 85.7% (95% CI, 71.5-94.6). A 5-marker signature derived from the HIV uninfected group (CCL1+RANTES+MIP-1α+procalcitonin+IP-10) performed in HIV-infected individuals with a sensitivity of 75.0% and a specificity of 96.7% after leave-one-out cross validation. A 2-marker signature (CCL1+TNF-α) identified in HIV-infected persons performed in HIV-uninfected with a sensitivity and specificity of 66.7% and 100% respectively in the test set., Conclusions: Plasma CCL1 and IL-2Ra have potential as biomarkers for differentiating TB disease from LTBI in low TB burden settings unaffected by HIV infection. Combinations between these and other biomarkers in bio-signatures for global use warrant further exploration., Competing Interests: Declaration of Competing Interest All other authors declare no competing interests., (Copyright © 2021. Published by Elsevier Ltd.)

Background: Tuberculosis is a chronic infectious disease caused by acid-fast mycobacteria from the Mycobacterium tuberculosis complex group. The disease spreads when people with pulmonary tuberculosis excrete bacteria when they cough, sneeze, laugh or speak. Prisons are often called reservoirs of patients with tuberculosis, posing a great threat to their staff. Longer working hours in prison and penitentiary facilities aid latent contamination among the prison staff. So far, there have been few works discussing latent tuberculosis infection issues among the prisoners and prison staff., Material and Methods: A total of 84 employees of penitentiary facilities located in the Lublin Voivodship were examined using the QuantiFERON-TB Gold In-Tube (QFT-GIT) test which was approved for use in 2005 by the U.S. Food and Drug Administration as an aid in the diagnosis of Mycobacterium tuberculosis . The material for the research included blood samples collected using the QFT-GIT., Results: Positive test results of latent tuberculosis infections were found in 16.6% of officers. The highest percentage with positive results of tuberculosis infections was found among the surveyed single women aged 36-57, working in penitentiary facilities. There have been no statistically significant differences between the position of officers and the risk factors increasing the chance of the latent tuberculosis infection. Work experience and contact with inmates were found to have an impact on tuberculosis infection., Conclusions: The obtained results partially confirm other authors' observations concerning the influence of the risk factors of latent tuberculosis infections in prisons. Work experience and contact with inmates have an impact on tuberculosis infections among the prison staff in the Lublin Voivodeship. Med Pr. 2021;72(4):415-22., (This work is available in Open Access model and licensed under a CC BY-NC 3.0 PL license.)

Eradication of tuberculosis (TB), caused by Mycobacterium tuberculosis ( Mtb ), has been a challenge due to its uncanny ability to survive in a dormant state inside host granulomas for decades. Mtb rewires its metabolic and redox regulatory networks to survive in the hostile hypoxic and nutrient-limiting environment, facilitating the formation of drug-tolerant persisters. Previously, we showed that protein kinase G (PknG), a virulence factor required for lysosomal escape, aids in metabolic adaptation, thereby promoting the survival of nonreplicating mycobacteria. Here, we sought to investigate the therapeutic potential of PknG against latent mycobacterium. We show that inhibition of PknG by AX20017 reduces mycobacterial survival in in vitro latency models such as hypoxia, persisters, and nutrient starvation. Targeting PknG enhances the bactericidal activity of the frontline anti-TB drugs in peritoneal macrophages. Deletion of pknG resulted in 5- to 15-fold-reduced survival of Mtb in chronically infected mice treated with anti-TB drugs. Importantly, in the Cornell mouse model of latent TB, the deletion of pknG drastically attenuated Mtb 's ability to resuscitate after antibiotic treatment compared with wild-type and complemented strains. This is the first study to investigate the sterilizing activity of pknG deletion and inhibition for adjunct therapy against latent TB in a preclinical model. Collectively, these results suggest that PknG may be a promising drug target for adjunct therapy to shorten the treatment duration and reduce disease relapse., (Copyright © 2021 American Society for Microbiology.)

Background: Diagnosis of active tuberculosis (ATB) currently relies on detection of Mycobacterium tuberculosis (Mtb). Identifying patients with extrapulmonary TB (EPTB) remains challenging because microbiological confirmation is often not possible. Highly accurate blood-based tests could improve diagnosis of both EPTB and pulmonary TB (PTB) and timely initiation of anti-TB therapy., Methods: A case-control study was performed using discriminant analyses to validate an approach using Mtb-specific CD4+T-cell activation markers in blood to discriminate PTB and EPTB from latent TB infection (LTBI) as well as EPTB from PTB in 270 Brazilian individuals. We further tested the effect of human immunodeficiency virus (HIV) coinfection on diagnostic performance. Frequencies of interferon-γ +CD4+T cells expressing CD38, HLADR, and/or Ki67 were assessed by flow cytometry., Results: EPTB and PTB were associated with higher frequencies of CD4+T cells expressing CD38, HLADR, or Ki67 compared with LTBI (all P values < .001). Moreover, frequencies of HLADR+ (P = .03) or Ki67+ (P < .001) cells accurately distinguished EPTB from PTB. HIV infection did not affect the capacity of these markers to distinguish ATB from LTBI or EPTB from PTB., Conclusions: Cell activation markers in Mtb-specific CD4+T cells distinguished ATB from LTBI and EPTB from PTB, regardless of HIV infection status. These parameters provide an attractive approach for developing blood-based diagnostic tests for both active and latent TB., (© The Author(s) 2019. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.)

Objective: HIV-infection increases the risk to progress to active-tuberculosis (TB). Detection of latent TB infection (LTBI) is needed to eventually propose preventive-therapy and reduce TB reservoir. QuantiFERON-TB Plus (QFT-Plus)-test identifies LTBI. Currently, only two studies on QFT-Plus accuracy in HIV-infected-population are available in high TB-endemic-countries. Therefore we aimed to evaluate the effect of HIV-infection on QFT-Plus accuracy to detect LTBI in a low TB-endemic-country., Methods: We enrolled 465 participants, among the 167 HIV-infected-persons: 32 with active-TB (HIV-TB), 45 remote-LTBI (HIV-LTBI) and 90 at low M. tuberculosis (Mtb)-infection risk. Among the 298 HIV-uninfected-persons: 170 with active-TB, 76 recent-LTBI, 34 remote-LTBI and 18 with low Mtb-infection risk., Results: QFT-Plus sensitivity was similar in TB regardless of HIV-status. CD4-count did not influence the distribution of IFN-γ values in HIV-TB and HIV-LTBI. Moreover HIV-LTBI and HIV-uninfected remote LTBI had a similar proportion of results in the uncertain range (IFNγ ≥0.2 ≤ 0.7 IU/ml) differently from those LTBI-persons reporting recent-exposure (p = 0.016). Cytometry results demonstrated that CD8-response was similar in HIV-infected- and -uninfected-persons whereas CD4-response was impaired in HIV-infected-persons (p = 0.011)., Conclusions: HIV-infection does not affect QFT-Plus response in active-TB, whereas the time of exposure influences the proportion of uncertain-results in LTBI., Competing Interests: Declaration of Competing Interest DG received consultant fees for public speaking in international meetings by Qiagen and Diasorin., (Copyright © 2020 The British Infection Association. Published by Elsevier Ltd. All rights reserved.)

Competing Interests: Declaration of competing interest None.

Mycobacterium tuberculosis is the leading cause of death worldwide from a single bacterial pathogen. The World Health Organization estimates that annually 1 million children have tuberculosis (TB) disease and many more harbor a latent form. Accurate estimates are hindered by under-recognition and challenges in diagnosis. To date, an accurate diagnostic test to confirm TB in children does not exist. Treatment is lengthy but outcomes are generally favorable with timely initiation. With the End TB Strategy, there is an urgent need for improved diagnostics and treatment to prevent the unnecessary morbidity and mortality from TB in children., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Tuberculosis (TB) remains a devastating disease, yet despite its enormous toll on global health, tools to control TB are insufficient and often outdated. TB Biomarkers (TB-BM) would constitute extremely useful tools to measure infection status and predict outcome of infection, vaccination or therapy. There are several types of TB-BM: Correlate of Infection; Correlate of TB Disease; Correlate of Increased Risk of Developing Active TB Disease; Correlate of the Curative Response to Therapy; and Correlate of Protection (CoP). Most TB-BM currently studied are host-derived BM, and consist of transcriptomic, proteomic, metabolomic, cellular markers or marker combinations ('signatures'). In particular, vaccine-inducible CoP are expected to be transformative in developing new TB vaccines as they will de-risk vaccine research and development (R&D) as well as human testing at an early stage. In addition, CoP could also help minimizing the need for preclinical studies in experimental animals. Of key importance is that TB-BM are tested and validated in different well-characterized human TB cohorts, preferably with complementary profiles and geographically diverse populations: genetic and environmental factors such as (viral) coinfections, exposure to non-tuberculous mycobacteria, nutritional status, metabolic status, age (infants vs children vs adolescents vs adults) and other factors impact host immune set points and host responses across different populations. In this study, we review the most recent advances in research into TB-BM for the diagnosis of active TB, risk of TB development and treatment-induced TB cure., (© 2018 Asian Pacific Society of Respirology.)

Objectives: The serological antibody detection tests offer several advantages for the rapid diagnosis of tuberculosis (TB). The Mycobacterium tuberculosis-specific antibody responses associated with different stages of TB infection remain to be investigated., Methods: The Pathozyme-Myco IgG (Myco G), Pathozyme TB Complex Plus (TB Complex), IBL M. tuberculosis IgG ELISA (IBL), Anda Biologicals TB IgG (Anda-TB), and T-SPOT.TB (T-SPOT) tests were performed for 133 active TB patients (ATB group), 131 controls (CON group), and 95 subjects with latent TB infection (LTBI group)., Results: The four serological tests all showed relatively low sensitivity in the ATB group but high specificity in the LTBI and CON groups. The antibody levels of the four serological tests were significantly higher in the ATB group than in the LTBI group. The same trend was observed between the LTBI and CON groups. The four serological tests demonstrated potential diagnostic value in discriminating ATB from LTBI. A combination of the Anda-TB and TB Complex tests exhibited the best diagnostic potential in discriminating ATB from LTBI, with a sensitivity of 89.4% and a specificity of 94.7%. Further, the diagnostic value of Anda-TB and TB Complex were validated in a prospective cohort including 106 patients with suspected ATB. Combined with the T-SPOT test, the tests showed a sensitivity of 87.2% and a specificity of 92.5% for discriminating ATB patients from all ATB suspected cases in the validation group., Conclusions: The antibody responses of the serological tests all showed significant differences between the ATB and LTBI groups. A combination of Anda-TB and the TB Complex test demonstrated high diagnostic potential in discriminating ATB from LTBI and may be an additional diagnostic tool in the diagnosis of M. tuberculosis infection., (Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Heat shock protein Hsp16.3 is closely related to latent Mycobacterium tuberculosis (MTB) infection and plays an important role in sustained survival when MTB is dormant. In this study, the Hsp16.3 gene mutant MTB H37Rv strain (Hsp16.3ΔMTB) was obtained through gene recombination and infected into murine RAW 264.7 macrophages. Western blotting and immunofluorescence showed increased expression of the autophagy-related protein LC3, and transmission electron microscopy showed significantly increased macrophage autophagosomes, suggesting that Hsp16.3ΔMTB facilitates murine macrophage autophagy. These findings have implications for preventing and controlling tuberculosis.

Mycobacterium tuberculosis is the leading cause of death worldwide from a single bacterial pathogen. The World Health Organization estimates that annually 1 million children have tuberculosis (TB) disease and many more harbor a latent form. Accurate estimates are hindered by under-recognition and challenges in diagnosis. To date, an accurate diagnostic test to confirm TB in children does not exist. Treatment is lengthy but outcomes are generally favorable with timely initiation. With the End TB Strategy, there is an urgent need for improved diagnostics and treatment to prevent the unnecessary morbidity and mortality from TB in children., (Copyright © 2017 Elsevier Inc. All rights reserved.)

In many countries with low to moderate tuberculosis (TB) incidence, cases have shifted to elderly persons. It is unclear, however, whether these cases are associated with recent Mycobacterium tuberculosis transmission or represent reactivation of past disease. During 2009-2015, we performed a population-based TB investigation in Yamagata Prefecture, Japan, using in-depth contact tracing and 24-loci variable-number tandem-repeat typing optimized for Beijing family M. tuberculosis strains. We analyzed 494 strains, of which 387 (78.3%) were derived from elderly patients. Recent transmission with an epidemiologic link was confirmed in 22 clusters (70 cases). In 17 (77.3%) clusters, the source patient was elderly; 11 (64.7%) of the 17 clusters occurred in a hospital or nursing home. In this setting, the increase in TB cases was associated with M. tuberculosis transmissions from elderly persons. Prevention of transmission in places where elderly persons gather will be an effective strategy for decreasing TB incidence among predominantly elderly populations.

The genome of Mycobacterium tuberculosis (Mtb) of latently infected individuals may hold the key to understanding the processes that lead to reactivation and progression to clinical disease. We report here analysis of pairs of Mtb isolates from putative prolonged latent TB cases. We identified two confirmed cases, and used whole genome sequencing to investigate the mutational processes that occur over decades in latent Mtb. We found an estimated mutation rate between 0.2 and 0.3 over 33 years, suggesting that latent Mtb accumulates mutations at rates similar to observations from cases of active disease., (Copyright © 2016 Elsevier GmbH. All rights reserved.)

Donor-derived tuberculosis (TB) is an increasingly recognized complication of solid organ transplantation. We report a case of isoniazid-resistant pulmonary TB in a lung transplant recipient. The patient acquired the infection from the lung donor who was previously empirically treated with isoniazid for latent TB. The case highlights the caveat that, while adequate treatment of latent TB with isoniazid is presumed, meticulous screening of donors is required., (© 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

This report demonstrates that using interferon gamma release assays to screen for latent tuberculosis infection in female commercial sex workers in an outreach sexual health clinic is feasible and acceptable. Routine interferon gamma release assay use successfully identified high numbers of latent tuberculosis infection. Innovative approaches to treatment and follow up were required to improve treatment adherence in this group. Direct observation of therapy within the sexual health clinic was also feasible. Successful follow up was dependent on the support of outreach workers, interpreters and tuberculosis nurses., (© The Author(s) 2015.)

Background: The durability of isoniazid preventive therapy (IPT) in preventing tuberculosis (TB) is limited in high-prevalence settings. The underlying mechanism (reactivation of persistent latent TB or reinfection) is not known. We aimed to investigate the timing of TB incidence during and after IPT and associated risk factors in a very high TB and HIV-prevalence setting, and to compare the observed rate with a modelled estimate of TB incidence rate after IPT due to reinfection., Methods: In a post-hoc analysis of a cluster-randomized trial of community-wide IPT among South African gold miners, all intervention arm participants that were dispensed IPT for at least one of the intended 9 months were included. An incident TB case was defined as any participant with a positive sputum smear or culture, or with a clinical TB diagnosis assigned by a senior study clinician. Crude TB incidence rates were calculated during and after IPT, overall and by follow-up time. HIV status was not available. Multivariable Cox regression was used to analyse risk factors by follow-up time after IPT. Estimates from a published mathematical model of trial data were used to calculate the average reinfection TB incidence in the first year after IPT., Results: Among 18,520 participants (96% male, mean age 41 years, median follow-up 2.1 years), 708 developed TB. The TB incidence rate during the intended IPT period was 1.3/100 person-years (pyrs; 95% confidence interval (CI), 1.0-1.6) and afterwards 2.3/100 pyrs (95% CI, 1.9-2.7). TB incidence increased within 6 months followed by a stable rate over time. There was no evidence for changing risk factors for TB disease over time after miners stopped IPT. The average TB incidence rate attributable to reinfection in the first year was estimated at 1.3/100 pyrs, compared to an observed rate of 2.2/100 pyrs (95% CI, 1.8-2.7)., Conclusions: The durability of protection by IPT was lost within 6-12 months in this setting with a high HIV prevalence and a high annual risk of M. tuberculosis infection. The observed rate was higher than the modelled rate, suggesting that reactivation of persistent latent infection played a role in the rapid return to baseline TB incidence.

Mycobacterium tuberculosis, the causative agent of tuberculosis (TB), has developed various mechanisms to survive and cause disease in the human host. Incomplete understanding of the complex microbe-host interactions has hindered the identification of suitable biomarkers to expedite the development of diagnostic tools, drugs and vaccines. The field effectiveness of directly observed therapy-short course has been compromised by the intrinsic limitations of sputum microscopy and suboptimal adherence to the long duration of treatment amid the HIV-TB syndemic and various socioeconomic constraints. While molecular tools are transforming the diagnostic processes, especially for multi-drug-resistant (MDR)-TB, drug development and service provision for MDR-TB seriously lag behind. Inappropriate management of detected MDR-TB cases may amplify drug resistance, jeopardizing future control. Targeted screening and treatment of latent infection with M. tuberculosis with the currently available immunodiagnostic tools and treatment regimens aim more for personal protection than major epidemiological impact or elimination. The interferon-γ release assays (IGRA) are not affected by cross-reaction to the bacillus Calmette-Guérin (BCG) vaccine and are increasingly used for such screening before initiation of biologics for treatment of rheumatoid arthritis and other autoimmune disorders. BCG offers only partial and unreliable protection against pulmonary TB in adults, the crucial transmission link for this airborne infection. Systems biology and vaccinomics may speed up vaccine research. The successful development of a fully effective TB vaccine that targets both growing bacteria and non-growing persisters may reflect a major breakthrough, as natural infection does not induce sufficient immunity to prevent reinfection., (© 2013 The Authors. Respirology © 2013 Asian Pacific Society of Respirology.)

Apremilast is a relatively new oral treatment for psoriasis, which reduces expression of pro‐inflammatory factors, including tumour necrosis factor‐α (TNFα), critical to the immune control of Mycobacterium tuberculosis infection. In randomised controlled trials (RCTs) for apremilast no new cases of active tuberculosis (TB) were identified, thus, screening for latent TB infection (LTBI) is not currently recommended prior to apremilast initiation. We describe a case of M.tuberculosis reactivation shortly after commencement of apremilast for psoriasis. We are recommending clinicians perform LTBI risk assessment in all patients, and appropriate LTBI screening in select populations prior to apremilast initiation. [ABSTRACT FROM AUTHOR]

Tuberculosis (TB), caused by Mycobacterium tuberculosis, is a significant global health problem. In immunocompetent individuals, the microorganism can remain in a latent, non‐contagious form, however, it may become active under conditions of immunosuppression. Tumour necrosis factor (TNF) inhibitors, which are frequently used for the management of immune‐mediated disorders like psoriasis, have been associated with a significantly increased risk of reactivating latent TB. Consequently, international guidelines recommend TB screening and preventive treatment before starting anti‐TNF therapy. These recommendations have extended to IL‐12/23, IL‐17, IL‐23 and TYK2 inhibitors under a caution principle, despite their different mechanisms of action. However, current evidence suggests that some of these agents are arguably not associated with an increased risk of TB reactivation or development of TB disease after infection, which calls for a critical reassessment of these guidelines. We have conducted a literature search evaluating the risk of TB reactivation associated with these innovative therapies, integrating findings from both randomized clinical trials and real‐world evidence. The identified evidence is limited but the low number of identified cases of reactivation with IL‐17 and IL‐23 inhibitors prompts reconsidering the need for preventive treatment for latent TB in all cases, regardless of biologic class or individual patient's risk of TB reactivation or drug toxicity. This review, along with the clinical insight of a panel of experts on behalf of the SPIN‐FRT, led to the development of these consensus recommendations for managing psoriasis treatment in patients with latent TB infection or at risk of TB infection, who are receiving or are intended to receive biologic and non‐biologic targeted therapies. These recommendations highlight the need for updates to the existing guidelines, aiming to provide a more differentiated approach that reflects the evolving landscape of psoriasis treatment and its implications for TB management. [ABSTRACT FROM AUTHOR]

The study aims to accurately identify differentially expressed genes (DEGs) and biological pathways in mycobacterial infections through bioinformatics for deeper disease understanding. Differentially expressed genes (DEGs) was explored by Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis. Unique DEGs were submitted on least absolute shrinkage and selection operator (LASSO) regression analysis. 1,057 DEGs from two GSE datasets were identified, which were closely connected with NTM/ latent TB infection (LTBI)/active TB disease (ATB). It was demonstrated that these DEGs are mainly associated with detoxification processes, and virus and bacterial infections. Moreover, the METTL7B gene was the most informative marker for distinguishing LTBI and ATB with an area under the curve (AUC) of 0.983 (95%CI: 0.964 to 1). The significantly upregulated HBA1/2 genes were the most informative marker for distinguishing between individuals of IGRA-HC/NTM and LTBI (P < 0.001). Moreover, the upregulated HBD gene was also differ between IGRA-HC/NTM and ATB (P < 0.001). We have identified gene signatures associated with Mycobacterium infection in whole blood, which could be significant for understanding the molecular mechanisms and diagnosis of NTM, LTBI, or ATB. [ABSTRACT FROM AUTHOR]

Background: Mycobacterium tuberculosis is the second most common infectious cause of death in adults worldwide. The ability of this organism to efficiently establish latent infection has enabled it to spread to nearly one-third of individuals worldwide. Approximately 8 million new cases of active tuberculosis disease occur each year, leading to about 1.7 million deaths. The disease incidence is magnified by the concurrent epidemic of human immunodeficiency virus infection. A total of 1.3 million people died from tuberculosis in 2022. In 2022, an estimated 10.6 million people fell ill with tuberculosis worldwide, including 5.8 million men, 3.5 million women, and 1.3 million children. We report a case of thyroid tuberculosis presenting as multinodular goiter. Neck ultrasound was done and revealed abscess collection on the background of multinodular colloid goiter. The diagnosis of thyroid tuberculosis was confirmed by a positive GeneXpert of the pus sample and the presence of extensive caseous necrosis on cytopathology examination. Furthermore, anterior neck swelling may provide a diagnostic challenge by clinically mimicking multinodular goiter or thyroid neoplasms. Owing to its rarity and its tendency to pose a clinical diagnostic challenge, we decided to report it. Case presentation: A 60-year-old retired female Ethiopian high-school teacher presented to University of Gondar Hospital, Gondar, Ethiopia with firm, nontender multinodular anterior neck swelling measuring at largest 2 × 3 cm that moves with swallowing. GeneXpert of the pus sample and cytopathology examination confirmed the diagnosis of thyroid tuberculosis, and the patient was started on 2 rifampicin−ethambutol−isoniazid−pyrazinamide/4 rifampicin−isoniazid 3 tablets by mouth/day, which is defined as the preferred first-line anti-tuberculosis regimen in Ethiopia, and pyridoxine 50 mg by mouth per day for 6 months. Since then, she has been followed with regular liver function tests. The patient has shown a smooth course with no significant adverse effects encountered. Currently, the patient has completed her anti-tuberculosis treatment and is doing well. Conclusion: In the clinical evaluation of a patient with anterior neck swelling, tuberculosis must be considered as a differential diagnosis in subjects from endemic areas for early diagnostic workup and management. [ABSTRACT FROM AUTHOR]

A study published in Clinical & Translational Medicine explores the potential of transfer RNA-derived small RNAs (tsRNAs) as diagnostic biomarkers for active tuberculosis (TB). The study identified 128 tsRNAs with differing expression patterns in peripheral blood mononuclear cells (PBMCs) of TB patients. Among these, tRF-Glu-TTC-026 showed promise as a diagnostic marker, with high sensitivity and specificity in distinguishing TB patients from non-TB individuals. Additionally, the study found that tRF-Glu-TTC-026 promotes the intracellular survival of Mycobacterium tuberculosis in macrophages by regulating macrophage polarization. Further research is needed to understand the mechanism and potential treatment strategies based on tsRNAs for TB control. [Extracted from the article]

Introduction: The unique dormancy of Mycobacterium tuberculosis plays a significant role in the major clinical treatment challenge of tuberculosis, such as its long treatment cycle, antibiotic resistance, immune escape, and high latent infection rate. Methods: To determine the function of MtrA, the only essential response regulator, one strategy was developed to establish its regulatory network according to high-quality genome-wide binding sites. Results and discussion: The complex modulation mechanisms were implied by the strong bias distribution of MtrA binding sites in the noncoding regions, and 32.7% of the binding sites were located inside the target genes. The functions of 288 potential MtrA target genes predicted according to 294 confirmed binding sites were highly diverse, and DNA replication and damage repair, lipid metabolism, cell wall component biosynthesis, cell wall assembly, and cell division were the predominant pathways. Among the 53 pathways shared between dormancy/resuscitation and persistence, which accounted for 81.5% and 93.0% of the total number of pathways, respectively, MtrA regulatory genes were identified not only in 73.6% of their mutual pathways, but also in 75.4% of the pathways related to dormancy/resuscitation and persistence respectively. These results suggested the pivotal roles of MtrA in regulating dormancy/resuscitation and the apparent relationship between dormancy/resuscitation and persistence. Furthermore, the finding that 32.6% of the MtrA regulons were essential in vivo and/or in vitro for M. tuberculosis provided new insight into its indispensability. The findings mentioned above indicated that MtrA is a novel promising therapeutic target for tuberculosis treatment since the crucial function of MtrA may be a point of weakness for M. tuberculosis. [ABSTRACT FROM AUTHOR]

Despite huge efforts, tuberculosis (TB) is still a major public health threat worldwide, with approximately 23% of the human population harboring a latent TB infection (LTBI). LTBI can reactivate and progress to active and transmissible TB disease, contributing to its spread within the population. The challenges in diagnosing and treating LTBI patients have been major factors contributing to this phenomenon. Exosomes offer a novel avenue for investigating the process of TB infection. In this study, we conducted small RNA sequencing to investigate the small RNA profiles of plasma exosomes derived from individuals with LTBI and healthy controls. Our findings revealed distinct miRNA profiles in the exosomes between the two groups. We identified 12 differentially expressed miRNAs through this analysis, which were further validated via qRT-PCR using the same exosomes. Notably, six miRNAs (hsa-miR-7850-5p, hsa-miR-1306-5p, hsa-miR-363-5p, hsa-miR-374a-5p, hsa-miR-4654, has-miR-6529-5p, and hsa-miR-140-5p) exhibited specifically elevated expression in individuals with LTBI. Gene ontology and KEGG pathway analyses revealed that the targets of these miRNAs were enriched in functions associated with ferroptosis and fatty acid metabolism, underscoring the critical role of these miRNAs in regulating the intracellular survival of Mycobacterium tuberculosis (Mtb). Furthermore, our results indicated that the overexpression of miR-7850-5p downregulated the expression of the SLC11A1 protein in both Mtb-infected and Mtb-uninfected THP1 cells. Additionally, we observed that miR-7850-5p promoted the intracellular survival of Mtb by suppressing the expression of the SLC11A1 protein. Overall, our findings provide valuable insights into the role of miRNAs and repetitive region-derived small RNAs in exosomes during the infectious process of Mtb and contribute to the identification of potential molecular targets for the detection and diagnosis of latent tuberculosis. [ABSTRACT FROM AUTHOR]

Background: Lipids are a key nutrient source for the growth and reproduction of Mycobacterium tuberculosis (Mtb). Urine-derived extracellular vesicles (EVs), because of its non-invasive sampling, lipid enrichment, and specific sorting character, have been recognized as a promising research target for biomarker discovery and pathogenesis elucidation in tuberculosis (TB). We aim to profile lipidome of Mtb-infected individuals, offer novel lipid signatures for the development of urine-based TB testing, and provide new insights into the lipid metabolism after Mtb infection. Methods: Urine-derived extracellular vesicles from 41 participants (including healthy, pulmonary tuberculosis, latent tuberculosis patients, and other lung disease groups) were isolated and individually detected using targeted lipidomics and proteomics technology platforms. Biomarkers were screened by multivariate and univariate statistical analysis and evaluated by SPSS software. Correlation analyses were performed on lipids and proteins using the R Hmisc package. Results: Overall, we identified 226 lipids belonging to 14 classes. Of these, 7 potential lipid biomarkers for TB and 6 for latent TB infection (LTBI) were identified, all of which were classified into diacylglycerol (DAG), monoacylglycerol (MAG), free fatty acid (FFA), and cholesteryl ester (CE). Among them, FFA (20:1) was the most promising biomarker target in diagnosing TB/LTBI from other compared groups and also have great diagnostic performance in distinguishing TB from LTBI with AUC of 0.952. In addition, enhanced lipolysis happened as early as individuals got latent Mtb infection, and ratio of raft lipids was gradually elevated along TB progression. Conclusion: This study demonstrated individualized lipid profile of urinary EVs in patients with Mtb infection, revealed novel potential lipid biomarkers for TB/LTBI diagnosis, and explored mechanisms by which EV lipid raft-dependent bio-processes might affect pathogenesis. It lays a solid foundation for the subsequent diagnosis and therapeutic intervention of TB. [ABSTRACT FROM AUTHOR]

We have identified an acyl-carrier protein, Rv0100, that is up-regulated in a dormancy model. This protein plays a critical role in the fatty acid biosynthesis pathway, which is important for energy storage and cell wall synthesis in Mycobacterium tuberculosis (MTB). Knocking out the Rv0100 gene resulted in a significant reduction of growth compared to wild-type MTB in the Wayne model of non-replicating persistence. We have also shown that Rv0100 is essential for the growth and survival of this pathogen during infection in mice and a macrophage model. Furthermore, knocking out Rv0100 disrupted the synthesis of phthiocerol dimycocerosates, the virulence-enhancing lipids produced by MTB and Mycobacterium bovis. We hypothesize that this essential gene contributes to MTB virulence in the state of latent infection. Therefore, inhibitors targeting this gene could prove to be potent antibacterial agents against this pathogen. [ABSTRACT FROM AUTHOR]

Tuberculosis (TB) transmission and prevalence are dynamic over time, and heterogeneous within populations. Public health programmes therefore require up-to-date, accurate epidemiological data to appropriately allocate resources, target interventions, and track progress towards End TB goals. Current methods of TB surveillance often rely on case notifications, which are biased by access to healthcare, and TB disease prevalence surveys, which are highly resource-intensive, requiring many tens of thousands of people to be tested to identify high-risk groups or capture trends. Surveys of "latent TB infection", or immunoreactivity to Mycobacterium tuberculosis (Mtb), using tests such as interferon-gamma release assays (IGRAs) could provide a way to identify TB transmission hotspots, supplementing information from disease notifications, and with greater spatial and temporal resolution than is possible to achieve in disease prevalence surveys. This cross-sectional survey will investigate the prevalence of Mtb immunoreactivity amongst young children, adolescents and adults in Blantyre, Malawi, a high HIV-prevalence city in southern Africa. Through this study we will estimate the annual risk of TB infection (ARTI) in Blantyre and explore individual- and area-level risk factors for infection, as well as investigating geospatial heterogeneity of Mtb infection (and its determinants), and comparing these to the distribution of TB disease case-notifications. We will also evaluate novel diagnostics for Mtb infection (QIAreach QFT) and sampling methodologies (convenience sampling in healthcare settings and community sampling based on satellite imagery), which may increase the feasibility of measuring Mtb infection at large scale. The overall aim is to provide high-resolution epidemiological data and provide new insights into methodologies which may be used by TB programmes globally. [ABSTRACT FROM AUTHOR]

This guideline aims to provide comprehensive and practical guidance for clinical management of tuberculosis in kidney transplant recipients. First, it summarizes the particularity of tuberculosis in kidney transplant recipients, and highlights the high incidence and diverse clinical manifestations. To better understand the patients' conditions, relevant assessment of tuberculosis is recommended before kidney transplantation. Extensive attention should be paid to the monitoring of tuberculosis after kidney transplantation. Regarding the diagnosis, the guideline explicitly introduces common diagnostic approaches for tuberculosis, and evaluates the applicability in kidney transplant recipients. After the diagnosis is confirmed, it discusses how to balance the treatment and rejection of tuberculosis under the background of immunosuppressants, and focuses upon the potential drug interaction. In terms of prevention, it emphasizes the screening of tuberculosis prior to kidney transplantation. This guideline is designed to deepen the understanding of medical staff for tuberculosis management in kidney transplant recipients, promote more effective clinical practice and improve the quality of life of the recipients. [ABSTRACT FROM AUTHOR]

Background: Tuberculosis (TB) is one of the most infectious diseases caused by Mycobacterium tuberculosis (M. tb), and the diagnosis of active tuberculosis (TB) and latent TB infection (LTBI) remains challenging. Methods: Gene expression files were downloaded from the GEO database to identify the differentially expressed genes (DEGs). The ssGSEA algorithm was applied to assess the immunological characteristics of patients with LTBI and TB. Weighted gene co-expression network analysis, protein-protein interaction network, and the cytoHubba plug-in of Cytoscape were used to identify the real hub genes. Finally, a diagnostic model was constructed using real hub genes and validated using a validation set. Results: Macrophages and natural killer cells were identified as important immune cells strongly associated with TB. In total, 726 mRNAs were identified as DEGs. MX1, STAT1, IFIH1, DDX58, and IRF7 were identified as real hub immune-related genes. The diagnostic model generated by the five real hub genes could distinguish active TB from healthy controls or patients with LTBI. Conclusion: Our study may provide implications for the diagnosis and drug development of M. tb infections. [ABSTRACT FROM AUTHOR]

ABSTRACT Most people infected with Mycobacterium tuberculosis (Mtb) are believed to be in a state of latent tuberculosis (TB) infection (LTBI). Although LTBI is asymptomatic and not infectious, there is a risk of developing active disease even decades after infection. Here, to characterize mutations acquired during LTBI, we collected and analyzed Mtb genomes from seven Japanese patient pairs, each pair consisting of two active TB patients whose starting dates of developing active disease were >3 years apart; one had a high suspicion of LTBI before developing active disease, whereas the other did not. Thereafter, we compared these genomes with those of longitudinal sample pairs within a host of chronic active TB infections combined with public data. The bacterial populations in patients with LTBI were genetically more homogeneous and accumulated single nucleotide polymorphisms (SNPs) slower than those from active disease. Moreover, the lower proportion of nonsynonymous SNPs indicated weaker selective pressures during LTBI than active disease. Finally, the different mutation spectrums indicated different mutators between LTBI and active disease. These results suggest that the likelihood of the acquisition of mutations responsible for antibiotic resistance and increased virulence was lower in the Mtb population from LTBI than active disease.IMPORTANCEControlling latent tuberculosis (TB) infection (LTBI) activation is an effective strategy for TB elimination, where understanding Mycobacterium tuberculosis (Mtb) dynamics within the host plays an important role. Previous studies on chronic active disease reported that Mtb accumulated genomic mutations within the host, possibly resulting in acquired drug resistance and increased virulence. However, several reports suggest that fewer mutations accumulate during LTBI than during the active disease, but the associated risk is largely unknown. Here, we analyzed the genomic dynamics of Mtb within the host during LTBI. Our results statistically suggest that Mtb accumulates mutations during LTBI, but most mutations are under low selective pressures, which induce mutations responsible for drug resistance and virulence. Thus, we propose that LTBI acts as a source for new TB disease rather than as a period for in-host genome evolution.

Mycobacterium tuberculosis (Mtb) can cause a latent infection that sometimes progresses to clinically active tuberculosis (TB). Type I interferons (IFN‐I) have been implicated in initiating the progression from latency to active TB, in part because IFN‐I stimulated genes are the earliest genes to be upregulated in patients as they advance to active TB. Plasmacytoid dendritic cells (pDCs) are major producers of IFN‐I during viral infections and in response to autoimmune‐induced neutrophil extracellular traps. pDCs have also been suggested to be the major producers of IFN‐I during Mtb infection of mice and nonhuman primates, but direct evidence has been lacking. Here, we found that Mtb did not stimulate isolated human pDCs to produce IFN‐I, but human neutrophils infected with Mtb‐activated co‐cultured pDCs to do so. Mtb‐infected neutrophils produced neutrophil extracellular traps, whose exposed DNA is a well‐known mechanism to activate pDCs to secrete IFN‐I. We conclude that pDCs contribute to the IFN‐I response during Mtb infection by interacting with infected neutrophils which may then promote Mtb pathogenesis. [ABSTRACT FROM AUTHOR]

Background: The aim of the study was to investigate whether the expression of CD27−CD38+ in interferon (IFN)-γ+CD4+ T cells stimulated by the specific antigen early secreted antigenic target-6 (ESAT-6)/culture filter protein-10 (CFP-10) could be a potential new therapeutic evaluation indicator for anti-tuberculosis (TB) treatment. Methods: Newly diagnosed active pulmonary TB patients, latent TB infection (LTBI) and healthy controls were enrolled from January 2021 to December 2021. PTB patients were treated by standard anti-TB regimen 2HREZ/4HR (2 months of isoniazid (H), rifampin (R), ethambutol (E), and pyrazinamide (Z) followed by 4 months of isoniazid (H) and rifampin (R)). The difference of CD27−CD38+ expression in IFN-γ+CD4+ T cells before treatment, 2 months after treatment, and 6 months after treatment were compared. Results: Total 45 PTB patients, 38 LTBI cases and 43 healthy controls were enrolled. The expression of CD27−CD38+ decreased significantly after anti-TB treatment and was comparable with that in LTBI and healthy controls when the 6-month anti-TB treatment course was completed. The decline rate of CD27−CD38+ between 6 months after treatment and baseline was positively correlated with erythrocyte sedimentation rate (r = 0.766, P < 0.0001), C-reactive protein (r = 0.560, P = 0.003) and chest computerized tomography severity score (r = 0.632, P = 0.0005). The area under receiver operator characteristic curve of CD27−CD38+ in distinguish pulmonary TB patients before and after treatment was 0.779. Conclusion: The expression of CD27−CD38+ in ESAT-6/CFP-10 stimulated IFN-γ+CD4+T cells can well reflect the changes of the disease before and after anti-TB treatment, which is expected to be a potential new therapeutic evaluation index. Clinical Registry number chiCTR1800019966. [ABSTRACT FROM AUTHOR]

Background: The war in Ukraine has led to significant migration to neighboring countries, raising public health concerns. Notable tuberculosis (TB) incidence rates in Ukraine emphasize the immediate requirement to prioritize approaches that interrupt the spread and prevent new infections. Methods: We conducted a prospective genomic surveillance study to assess migration's impact on TB epidemiology in the Czech Republic and Slovakia. Mycobacterium tuberculosis isolates from Ukrainian war refugees and migrants, collected from September 2021 to December 2022 were analyzed alongside 1574 isolates obtained from Ukraine, the Czech Republic, and Slovakia. Results: Our study revealed alarming results, with historically the highest number of Ukrainian tuberculosis patients detected in the host countries. The increasing number of cases of multidrug-resistant TB, significantly linked with Beijing lineage 2.2.1 (p < 0.0001), also presents substantial obstacles to control endeavors. The genomic analysis identified the three highly related genomic clusters, indicating the recent TB transmission among migrant populations. The largest clusters comprised war refugees diagnosed in the Czech Republic, TB patients from various regions of Ukraine, and incarcerated individuals diagnosed with pulmonary TB specialized facility in the Kharkiv region, Ukraine, pointing to a national transmission sequence that has persisted for over 14 years. Conclusions: The data showed that most infections were likely the result of reactivation of latent disease or exposure to TB before migration rather than recent transmission occurring within the host country. However, close monitoring, appropriate treatment, careful surveillance, and social support are crucial in mitigating future risks, though there is currently no evidence of local transmission in EU countries. [ABSTRACT FROM AUTHOR]

Introduction: Tuberculosis (TB) remains a major public health problem in India. Individuals with latent infection do not have active disease and cannot spread Tuberculosis Infection (TBI). The prevalence of latent TB in India is very high, ranging from 40-50%. About 5 to 10% of them may convert into active TB disease. The national program primarily recommends treatment for active TB, while treatment of latent TB is recommended only in special situations. Aim: To assess the efficacy of short-course weekly Isoniazid and Rifapentine (HP) regimen as Tuberculosis Preventive Treatment (TPT) among various risk groups. Materials and Methods: A systematic review and meta-analysis were conducted, involving of about 10 Randomised Control Trials (RCTs). Studies published between 2006 and 2023 were included. Online databases such as PubMed, Google Scholar, Clinical Trial Registry India, and grey literature were searched using keywords like Isoniazid, Rifapentine, and trial. Results: In terms of TB incidence, the pooled risk ratio favoured the weekly HP regimen, estimated at 0.69 (0.49, 0.97, 95% CI). Regarding the incidence of hepatotoxicity, the weekly HP regimen showed neither superiority nor inferiority to comparators, with a pooled risk ratio of 0.50 (0.23, 1.05, 95% CI). The odds of completing treatment were 2.19 times greater for the weekly HP regimen than for controls, with a pooled odds ratio of 2.19 (1.64, 2.92; 95% CI). Conclusion: The weekly HP regimen is superior to other regimens in reducing the incidence of TB. Additionally, the duration of the HP regimen is shorter compared to the commonly advised nine-month Isoniazid regimen. Compared with the daily dosage of Isoniazid, the weekly HP regimen offers better compliance. It also exhibits a significantly higher treatment completion rate. In summary, the weekly HP regimen is superior to other regimens. [ABSTRACT FROM AUTHOR]

Introduction: The Metagenomics next-generation sequencing (mNGS) and GeneXpert MTB/RIF assay (Xpert) exhibited a sensitivity for tuberculosis (TB) diagnostic performance. Research that directly compared the clinical performance of ddPCR analysis, mNGS, and Xpert in mycobacterium tuberculosis complex (MTB) infection has not been conducted. Methods: The study aimed to evaluate the diagnostic performance of ddPCR compared to mNGS and Xpert for the detection of MTB in multiple types of clinical samples. The final clinical diagnosis was used as the reference standard. Results: Out of 236 patients with suspected active TB infection, 217 underwent synchronous testing for tuberculosis using ddPCR, Xpert, and mNGS on direct clinical samples. During follow-up, 100 out of 217 participants were diagnosed with MTB infection. Compared to the clinical final diagnosis, ddPCR produced the highest sensitivity of 99% compared with mNGS (86%) and Xpert (64%) for all active MTB cases. Discussion: Twenty-two Xpert-negative samples were positive in mNGS tests, which confirmed the clinical diagnosis results from ddPCR and clinical manifestation, radiologic findings. Thirteen mNGS-negative samples were positive in ddPCR assays, which confirmed the clinical final diagnosis.ddPCR provides a higher sensitive compared to Xpert and mNGS for MTB diagnosis, as defined by the high concordance between ddPCR assay and clinical final diagnosis. [ABSTRACT FROM AUTHOR]

The ability of Mycobacterium tuberculosis to remain dormant after primary infection represents the prime cause of new TB cases throughout the world. Hence, diagnosis and treatment of individuals hosting dormant mycobacterium is one of the crucial strategies to be adopted for the prevention of Tuberculosis. Among many strategies unleashed by the latent bacterium, one of them is scavenging host cholesterol for carbon source. Cholesterol modifies lipid membranes over many scales and here, its effect on mycobacterial membrane biophysics and the subsequent effect on partitioning of antibiotics into cholesterol‐ enriched mycobacterial membranes was investigated. Our research showed that cholesterol alters the phase state behavior of mycobacterial outer membrane lipids by enhancing the overall membrane order at the headgroup and acyl chain region and is integrated into both ordered and disordered domains/phases, with a preference for the latter. Exogenous cholesterol further alters the drug partitioning behavior of structurally different drugs, pointing to a larger clinical potential of using more hydrophobic medications to target dormant bacteria. [ABSTRACT FROM AUTHOR]

Some genetic variations in cytokine genes can alter their expression and influence the evolution of Mycobacterium tuberculosis (Mtb) infection. This study aimed to investigate the association of polymorphisms in cytokine genes and variability in plasma levels of cytokines with the development of tuberculosis (TB) and latent tuberculosis infection (LTBI). Blood samples from 245 patients with TB, 80 with LTBI, and healthy controls (n = 100) were included. Genotyping of the IFNG +874A/T, IL6 -174G/C, IL4 -590C/T, and IL10 -1082A/G polymorphisms was performed by real-time PCR, and cytokine levels were determined by flow cytometry. Higher frequencies of genotypes AA (IFNG +874A/T), GG (IL6 -174G/C), TT (IL4 -590C/T), and GG (IL10 -1082A/G) were associated with an increased risk of TB compared to that of LTBI (p = 0.0027; p = 0.0557; p = 0.0286; p = 0.0361, respectively) and the control (p = <0.0001, p = 0.0021; p = 0.01655; p = 0.0132, respectively). In combination, the A allele for IFNG +874A/T and the T allele for IL4 -590C/T were associated with a higher chance of TB (p = 0.0080; OR = 2.753 and p < 0.0001; OR = 3.273, respectively). The TB group had lower levels of IFN-γ and higher concentrations of IL-6, IL-4, and IL-10. Cytokine levels were different between the genotypes based on the polymorphisms investigated (p < 0.05). The genotype and wild-type allele for IFNG +874A/T and the genotype and polymorphic allele for IL4 -590C/T appear to be more relevant in the context of Mtb infection, which has been associated with the development of TB among individuals infected by the bacillus and with susceptibility to active infection but not with susceptibility to latent infection. [ABSTRACT FROM AUTHOR]

Tuberculosis (TB) is an infectious disease resulting in millions of deaths annually worldwide. TB treatment is challenging due to a huge number of global latent infections and due to multidrug-resistant forms of TB. Inhaled administration of anti-TB drugs using dry powder inhalers has various advantages over oral administration due to its direct drug delivery and minimization of systemic side effects. Pretomanid (PA-824, PA) is a relatively new drug with potent activity against both active and latent forms of Mycobacterium tuberculosis (Mtb). It is also known for its synergistic effects in combination with pyrazinamide (PYR) and moxifloxacin (MOX). Fixed-dose combination powder formulations of either PYR and PA or PYR and MOX were prepared for inhaled delivery to the deep lung regions where the Mtb habitats were located. Powder formulations were prepared by spray drying using L-leucine as the aerosolization enhancer and were characterized by their particle size, morphology and solid-state properties. In vitro aerosolization behaviour was studied using a Next Generation Impactor, and stability was assessed after storage at room temperature and 30% relative humidity for three months. Spray drying with L-leucine resulted in spherical dimpled particles, 1.9 and 2.4 µm in size for PYR-PA and PYR-MOX combinations, respectively. The powder formulations had an emitted dose of >83% and a fine particle fraction of >65%. PA and MOX showed better stability in the combination powders compared to PYR. Combination powder formulations with high aerosolization efficiency for direct delivery to the lungs were developed in this study for use in the treatment of latent and multidrug-resistant TB infections. [ABSTRACT FROM AUTHOR]

Key Clinical Message: Disseminated tuberculosis (TB) resulting from lymphohematogenous dissemination of Mycobacterium tuberculosis during primary infection or reactivation of latent disease is rare among young immunocompetent patients. Central nervous system TB (CNS TB) is one of the most challenging clinical diagnoses with high fatality. Here, we describe a young immunocompetent female with no known comorbidities initially presented with military pulmonary TB and later developed CNS TB. This presentation of disseminated TB in immunocompetent patient warrant early diagnosis and treatment. [ABSTRACT FROM AUTHOR]

In recognition of the high rates of undetected tuberculosis in the community, the World Health Organization (WHO) encourages targeted active case finding (ACF) among “high-risk” populations. While this strategy has led to increased case detection in these populations, the epidemic impact of these interventions has not been demonstrated. Historical data suggest that population-wide (untargeted) ACF can interrupt transmission in high-incidence settings, but implementation remains lacking, despite recent advances in screening tools. The reservoir of latent infection—affecting up to a quarter of the global population –complicates elimination efforts by acting as a pool from which future tuberculosis cases may emerge, even after all active cases have been treated. A holistic case finding strategy that addresses both active disease and latent infection is likely to be the optimal approach for rapidly achieving sustainable progress toward TB elimination in a durable way, but safety and cost effectiveness have not been demonstrated. Sensitive, symptom-agnostic community screening, combined with effective tuberculosis treatment and prevention, should eliminate all infectious cases in the community, whilst identifying and treating people with latent infection will also eliminate tomorrow’s tuberculosis cases. If real strides toward global tuberculosis elimination are to be made, bold strategies are required using the best available tools and a long horizon for cost-benefit assessment.

Background: Monocyte miRNAs govern both protective and pathological responses during tuberculosis (TB) through their differential expression and emerged as potent targets for biomarker discovery and host-directed therapeutics. Thus, this study examined the miRNA profile of sorted monocytes across the TB disease spectrum [drug-resistant TB (DR-TB), drug-sensitive TB (DS-TB), and latent TB] and in healthy individuals (HC) to understand the underlying pathophysiology and their regulatory mechanism. Methods: We sorted total monocytes including three subsets (HLA-DR+ CD14+, HLA-DR+ CD14+ CD16+, and HLA-DR+ CD16+ cells) from peripheral blood mononuclear cells (PBMCs) of healthy and TB-infected individuals through flow cytometry and subjected them to NanoString-based miRNA profiling. Results: The outcome was the differential expression of 107 miRNAs particularly the downregulation of miRNAs in the active TB groups (both drug-resistant and drug-sensitive). The miRNA profile revealed differential expression signatures: i) decline of miR-548m in DR-TB alone, ii) decline of miR-486-3p in active TB but significant elevation only in LTB iii) elevation of miR-132-3p only in active TB (DR-TB and DS-TB) and iv) elevation of miR-150-5p in DR-TB alone. The directionality of functions mediated by monocyte miRNAs from Gene Set Enrichment Analysis (GSEA) facilitated two phenomenal findings: i) a bidirectional response between active disease (activation profile in DR-TB and DS-TB compared to LTB and HC) and latent infection (suppression profile in LTB vs HC) and ii) hyper immune activation in the DR-TB group compared to DS-TB. Conclusion: Thus, monocyte miRNA signatures provide pathological clues for altered monocyte function, drug resistance, and disease severity. Further studies on monocyte miRNAs may shed light on the immune regulatory mechanism for tuberculosis. [ABSTRACT FROM AUTHOR]

Early Secreted Antigenic Target 6 kDa (ESAT6) is a potent immunogenic protein secreted by the bacteria causing tuberculosis, i.e., Mycobacterium tuberculosis. Another highly immunogenic culture filtrate protein whose gene is linked to ESAT6/ESXA is known as CFP10/ESXB. Because of their high immunogenicity and specificity to M. tuberculosis, these proteins have been proposed as a vaccine to prevent tuberculosis and diagnose the active/latent disease. However, the same proteins cannot be used for prevention and diagnosis because immunized but healthy people will also show a positive response and be falsely reported as diseased. Therefore, in this review article, the search was made to identify if any other ESAT6-like proteins exist in the M. tuberculosis genome. The search identified 21 additional ESAT-like proteins, i.e., ESXC to ESXW. Immunological characterization has shown that some of them (especially ESXV) were able to induce immune responses in vitro with cells obtained from tuberculosis patients and healthy donors. When the protein ESXV was tested in different recombinant forms (expressed in Escherichia coli, mycobacterial vectors, and DNA plasmids) and injected in mice, immune responses were induced to multiple epitopes of the protein. Furthermore, immunization of mice with ESXV protected them from infection with M. tuberculosis. The same protein was also able to protect mice against the induction of asthma. These results suggest that ESXV has the potential to protect against two major diseases in the world, i.e., tuberculosis and asthma, and hence may be used as a common vaccine for both diseases. [ABSTRACT FROM AUTHOR]