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Cell Proliferation Jul 2024Tuberculosis (TB) is a chronic disease caused by Mycobacterium tuberculosis (M.tb) and responsible for millions of deaths worldwide each year. It has a complex... (Review)
Review
Tuberculosis (TB) is a chronic disease caused by Mycobacterium tuberculosis (M.tb) and responsible for millions of deaths worldwide each year. It has a complex pathogenesis that primarily affects the lungs but can also impact systemic organs. In recent years, single-cell sequencing technology has been utilized to characterize the composition and proportion of immune cell subpopulations associated with the pathogenesis of TB disease since it has a high resolution that surpasses conventional techniques. This paper reviews the current use of single-cell sequencing technologies in TB research and their application in analysing specimens from various sources of TB, primarily peripheral blood and lung specimens. The focus is on how these technologies can reveal dynamic changes in immune cell subpopulations, genes and proteins during disease progression after M.tb infection. Based on the current findings, single-cell sequencing has significant potential clinical value in the field of TB research. Next, we will focus on the real-world applications of the potential targets identified through single-cell sequencing for diagnostics, therapeutics and the development of effective vaccines.
PubMed: 38956399
DOI: 10.1111/cpr.13698 -
NPJ Vaccines Jul 2024The Mycobacterial growth inhibition assay (MGIA) is an ex-vivo assay used to measure the overall functional immune response elicited by infection or vaccination. In...
The Mycobacterial growth inhibition assay (MGIA) is an ex-vivo assay used to measure the overall functional immune response elicited by infection or vaccination. In tuberculosis (TB) vaccine development, MGIA is a potentially important tool for preclinical evaluation of early-stage vaccine candidates to complement existing assays, and to potentially reduce the need for lengthy and costly pathogenic Mycobacterium tuberculosis (Mtb) animal challenge experiments. The conventional method of MGIA in mice entails directly infecting mixed cell cultures, most commonly splenocytes, from immunised mice with mycobacteria. However, this direct infection of mixed cell populations may yield unreliable results and lacks sufficient sensitivity to discriminate well between different vaccines due to the low number of mycobacteria-permissive cells. Here, we modified the assay by inclusion of mycobacteria-infected congenic murine macrophage cell lines as the target cells, and by measuring the total number of killed cells rather than the relative reduction between different groups. Thus, using splenocytes from Mycobacterium bovis BCG immunised mice, and J774 and MH-S (BALB/c background) or BL/6-M (C57Bl/6 background) macrophage cell lines, we demonstrated that the modified assay resulted in at least 26-fold greater mycobacterial killing per set quantity of splenocytes as compared to the conventional method. This increased sensitivity of measuring mycobacterial killing was confirmed using both the standard culture forming unit (CFU) assay and luminescence readings of luciferase-tagged virulent and avirulent mycobacteria. We propose that the modified MGIA can be used as a highly calibrated tool for quantitating the killing capacity of immune cells in preclinical evaluation of vaccine candidates for TB.
PubMed: 38956057
DOI: 10.1038/s41541-024-00906-z -
Saudi Medical Journal Jul 2024To evaluate cytokine profiles and interferon-gamma release assay (IGRA) for their diagnostic capabilities in the differentiation of tuberculosis (TB) from non-TB...
OBJECTIVES
To evaluate cytokine profiles and interferon-gamma release assay (IGRA) for their diagnostic capabilities in the differentiation of tuberculosis (TB) from non-TB conditions, as well as smear-negative pulmonary tuberculosis (SNPT) from smear-positive pulmonary tuberculosis (SPPT).
METHODS
A total of 125 participants were included, 77 of whom had TB and 48 who didn't, and demographic, clinical, and laboratory data were collected, including cytokine levels and IGRA results. The TB patients were further divided into 2 subgroups: SNPT (n=42) and SPPT (n=35).
RESULTS
Compared to non-TB, the TB group had lower BMI, higher WBC, neutrophils, monocytes, ESR and CRP (<0.05). TB patients showed higher IL-2, IL-6, IFN-γ, IL-8 (<0.001) and higher IGRA positivity (88.3% versus [vs.] 29.2%, <0.001). Between SNPT and SPPT, moderate effect sizes were observed for IFN-α, IL-2, IL-10, IL-8 (Cohen's d 0.59-0.76), with lower IGRA positivity in SNPT (81.0% vs. 97.1%, =0.015). ROC analysis indicated IFN-α, IL-2, IL-10, IL-8 had moderate accuracy for SNPT diagnosis (AUCs 0.668-0.734), and combining these improved accuracy (AUC 0.759, 80% sensitivity, 64.2% specificity).
CONCLUSION
A multi-biomarker approach combining these cytokines demonstrates enhanced diagnostic accuracy for tuberculosis.
Topics: Humans; Tuberculosis, Pulmonary; Male; Female; Cytokines; Adult; Middle Aged; Retrospective Studies; Interferon-gamma Release Tests; Interleukin-2; Interleukin-8; ROC Curve; Interleukin-6; Interleukin-10
PubMed: 38955446
DOI: 10.15537/smj.2024.45.7.20240310 -
The American Journal of Tropical... Jul 2024Latin American region is a high-burden setting for tuberculosis where multidrug-resistant tuberculosis (MDR-TB) is among the main challenge to move forward the End TB...
Latin American region is a high-burden setting for tuberculosis where multidrug-resistant tuberculosis (MDR-TB) is among the main challenge to move forward the End TB Strategy goals. It has been shown that MDR-TB is associated to certain Mycobacterium tuberculosis (MTB) lineages like L2-Beijing sublineage or L4-LAM. Although L2-Beijing is present in South America, the L4 lineage is the most prevalent with values ranging from 75% to 99% depending on the country. Within L4, Latin American-Mediterranean (LAM) family is the most prevalent. Moreover, within LAM, RDRio subfamily is present in high prevalence in several countries in South America like Venezuela or Brazil. RDRio has been associated to MDR-TB in several studies in Brazil but more epidemiological information is needed for South America. Here we discuss the problem of MDR-TB in Latin America and the potential threat that RDRio could represent. At this time, more molecular epidemiology studies are necessary to improve TB surveillance programs in Latin America by tracking MTB strains potentially responsible for MDR-TB spread.
PubMed: 38955162
DOI: 10.4269/ajtmh.24-0073 -
Clinical Infectious Diseases : An... Jul 2024Interferon-gamma release assays (IGRA) are widely used for diagnosis of latent tuberculosis infection. However, with repeat testing, IGRA transformation (conversion or...
BACKGROUND
Interferon-gamma release assays (IGRA) are widely used for diagnosis of latent tuberculosis infection. However, with repeat testing, IGRA transformation (conversion or reversion) may be detected and is challenging to interpret. We reviewed the frequency of and risk factors for IGRA transformation.
METHODS
We screened public databases for studies of human participants that reported the frequency of IGRA transformation. We extracted study and subject characteristics, details of IGRA testing and results. We calculated the pooled frequency of IGRA transformation (and transient transformation) and examined associated risk factors.
RESULTS
The pooled frequency of IGRA conversion or reversion from 244 studies was estimated at 7.3% (95% CI 6.1-8.5%) or 22.8% (20.1-25.7%), respectively. Transient conversion or reversion were estimated at 46.0% (35.7-56.4%) or 19.6% (9.2-31.7%) of conversion or reversion events respectively. Indeterminate results seldom reverted to positive (1.2% [0.1-3.5%]). IGRA results in the borderline positive or negative range were associated with increased risk of conversion or reversion (pooled OR: conversion, 4.15 [3.00-5.30]; reversion, 4.06 [3.07-5.06]). BCG vaccination was associated with decreased risk of conversion (0.70, 0.56-0.84), cigarette smoking with decreased risk of reversion (0.44, 0.06-0.82), and female sex with decreased risk of either conversion or reversion (conversion, 0.66 [0.58-0.75]; reversion, 0.46 [0.31-0.61]).
CONCLUSIONS
IGRA conversion is less common than reversion, and frequently transient. Research is needed to determine whether individuals with reversion would benefit from tuberculosis preventive treatment. Re-testing of people with indeterminate results is probably not indicated, since indeterminate results seldom revert to positive.
PubMed: 38954503
DOI: 10.1093/cid/ciae357 -
Organic Letters Jul 2024We herein report for the first time the inter- and intramolecular orthogonal cleavage of two -nitrobenzyl (NB) analogues. It is shown that the nitroveratryl (NV) group...
We herein report for the first time the inter- and intramolecular orthogonal cleavage of two -nitrobenzyl (NB) analogues. It is shown that the nitroveratryl (NV) group can be photolyzed with high priority when NV and -nitrobenzyl carbonate (NBC) are used together as the protecting groups of glycans. Notably, the photolytic products could be used directly in the subsequent glycosylation without further purification. With the above-mentioned orthogonal photolabile protecting group strategy in hand, a tetrasaccharide and a derivative of glucosyl glycerol were rapidly prepared.
PubMed: 38953872
DOI: 10.1021/acs.orglett.4c01906 -
Cureus May 2024Introduction Pulmonary tuberculosis (TB) remains a global health concern, exacerbated by the emergence of extensively drug-resistant (XDR) strains of . This study...
Introduction Pulmonary tuberculosis (TB) remains a global health concern, exacerbated by the emergence of extensively drug-resistant (XDR) strains of . This study employs advanced molecular techniques, specifically polymerase chain reaction (PCR) profiling, to comprehensively characterize the genetic landscape of XDR pathogenic bacteria in patients diagnosed with pulmonary TB. The objective of the study is to elucidate the genes that are associated with drug resistance in pulmonary TB strains through the application of PCR and analyze specific genetic loci that contribute to the development of resistance against multiple drugs. Materials and methods A total of 116 clinical samples suspected of TB were collected from the tertiary healthcare setting of Saveetha Medical College and Hospitals for the identification of MTB, which includes sputum (n = 35), nasal swabs (n = 17), blood (n = 44), and bronchoalveolar lavage (BAL) (n = 20). The collected specimens were processed and subjected to DNA extraction. As per the protocol, reconstitution of the DNA pellet was carried out. The reconstituted DNA was stored at -20 °C for the PCR assay. From the obtained positive sample specimens, XDR pulmonary TB specimens were focused on the targeted genes, specifically the gene for rifampicin resistance, , and gene for thepromoter region for isoniazid resistance. Results Out of a total of 116 samples obtained, 53 tested positive for pulmonary TB, indicative of a mycobacterial infection. Among these positive cases, 43 patients underwent treatment at a tertiary healthcare facility. Subsequently, a PCR assay was performed with the extracted DNA for the target genes , , and . Specifically, 22 sputum samples exhibited gene expression for , , and , while nine nasal swabs showed expression of the and genes. Additionally, gene expression was detected in seven blood specimens, and both and genes were expressed in five BAL samples. Conclusion The swift diagnosis and efficient treatment of XDR-TB can be facilitated by employing advanced and rapid molecular tests and oral medication regimens. Utilizing both newly developed and repurposed anti-TB drugs like pretomanid, bedaquiline, linezolid, and ethionamide. Adhering to these current recommendations holds promise for managing XDR-TB effectively. Nevertheless, it is significant to conduct well-designed clinical trials and studies to further evaluate the efficacy of new agents and shorter treatment regimens, thus ensuring continuous improvement in the management of this challenging condition.
PubMed: 38953074
DOI: 10.7759/cureus.61424 -
Cureus May 2024Tuberculosis is a disease with presentations both in the lungs and at other extrapulmonary sites. While pulmonary tuberculosis constitutes a significant proportion of...
Tuberculosis of the Cervical Vertebrae With Retropharyngeal and Parapharyngeal Abscesses Due to Staphylococcus aureus and Mycobacterium tuberculosis in an Adult: A Report of a Rare Case.
Tuberculosis is a disease with presentations both in the lungs and at other extrapulmonary sites. While pulmonary tuberculosis constitutes a significant proportion of total tuberculosis cases, extrapulmonary cases with infections at rare sites are also documented. Herein, an exceedingly rare case of tuberculosis of the cervical vertebrae with retropharyngeal and parapharyngeal abscesses due to and in a young Indian male is presented. The rarity of the locations of the lesions with coinfections with two bacteria made the diagnosis challenging. Besides, the potential for a retropharyngeal abscess to compress the airway is an emergency situation. However, the ultimate diagnosis was achieved with the help of a radiograph of the neck, contrast-enhanced computed tomography of the neck, fine-needle aspiration cytology, and a cartridge-based nucleic acid amplification test. He was initiated on appropriate antibiotics and antituberculous chemotherapy per his weight.
PubMed: 38953070
DOI: 10.7759/cureus.61412 -
Frontiers in Microbiology 2024The unique dormancy of plays a significant role in the major clinical treatment challenge of tuberculosis, such as its long treatment cycle, antibiotic resistance,...
INTRODUCTION
The unique dormancy of 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 and/or for 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 .
PubMed: 38952446
DOI: 10.3389/fmicb.2024.1415554 -
Zhongguo Xue Xi Chong Bing Fang Zhi Za... Jun 2024To evaluate the auxiliary diagnostic value of T cells spot test of infection (T-SPOT.TB) for pulmonary and extra-pulmonary tuberculosis among the elderly.
OBJECTIVE
To evaluate the auxiliary diagnostic value of T cells spot test of infection (T-SPOT.TB) for pulmonary and extra-pulmonary tuberculosis among the elderly.
METHODS
A total of 173 elderly patients at ages of 60 years and older and with suspected tuberculosis that were admitted to People's Hospital of Xinjiang Uygur Autonomous Region during the period from October 2022 through February 2024 were enrolled, and all patients underwent T-SPOT.TB, acid fast staining and GeneXpert MTB/RIF tests. The etiological tests of MTB served as a gold standard, and the diagnostic values of T-SPOT.TB, acid fast staining and GeneXpert MTB/RIF tests for pulmonary and extra-pulmonary tuberculosis were compared among the elderly patients.
RESULTS
Of the 173 elderly patients suspected of tuberculosis, there were 44 patients definitely diagnosed with pulmonary tuberculosis, 30 cases with extra-pulmonary tuberculosis, and 99 cases without tuberculosis. The sensitivities of T-SPOT.TB, acid fast staining and GeneXpert MTB/RIF tests were 86.5%, 27.0% and 54.1% for diagnosis of tuberculosis. The sensitivities of T-SPOT.TB were 86.4% and 86.7% for diagnosis of pulmonary tuberculosis and extra-pulmonary tuberculosis, with an 80.8% specificity for diagnosis of tuberculosis. The sensitivities of GeneXpert MTB/RIF were 56.8% and 50.0% for diagnosis of pulmonary tuberculosis and extra-pulmonary tuberculosis, with a 100.0% specificity each, and the sensitivities of acid fast staining were 31.8% and 20.0% for diagnosis of pulmonary tuberculosis and extra-pulmonary tuberculosis, with a 100.0% specificity each. In addition, the areas under the receiver operating characteristic curve were 0.836, 0.635 and 0.770 for diagnosis of tuberculosis with T-SPOT.TB, acid fast staining and GeneXpert MTB/RIF tests among the elderly patients, respectively.
CONCLUSIONS
T-SPOT.TB has a high auxiliary diagnostic value for both pulmonary and extra-pulmonary tuberculosis among elderly patients.
Topics: Humans; Aged; Mycobacterium tuberculosis; Male; Female; Tuberculosis, Pulmonary; Middle Aged; Tuberculosis; Aged, 80 and over; T-Lymphocytes; Sensitivity and Specificity; Tuberculosis, Extrapulmonary
PubMed: 38952319
DOI: 10.16250/j.32.1374.2024121