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1.
Front Cell Infect Microbiol ; 13: 1192134, 2023.
Article in English | MEDLINE | ID: covidwho-20237402

ABSTRACT

Tuberculosis, caused by Mycobacterium tuberculosis (MTB), is the second leading cause of death after COVID-19 pandemic. Here, we coupled multiple cross displacement amplification (MCDA) technique with CRISPR-Cas12a-based biosensing system to design a novel detection platform for tuberculosis diagnosis, termed MTB-MCDA-CRISPR. MTB-MCDA-CRISPR pre-amplified the specific sdaA gene of MTB by MCDA, and the MCDA results were then decoded by CRISPR-Cas12a-based detection, resulting in simple visual fluorescent signal readouts. A set of standard MCDA primers, an engineered CP1 primer, a quenched fluorescent ssDNA reporter, and a gRNA were designed targeting the sdaA gene of MTB. The optimal temperature for MCDA pre-amplification is 67°C. The whole experiment process can be completed within one hour, including sputum rapid genomic DNA extraction (15 minutes), MCDA reaction (40 minutes), and CRISPR-Cas12a-gRNA biosensing process (5 minutes). The limit of detection (LoD) of the MTB-MCDA-CRISPR assay is 40 fg per reaction. The MTB-MCDA-CRISPR assay does not cross reaction with non-tuberculosis mycobacterium (NTM) strains and other species, validating its specificity. The clinical performance of MTB-MCDA-CRISPR assay was higher than that of the sputum smear microscopy test and comparable to that of Xpert method. In summary, the MTB-MCDA-CRISPR assay is a promising and effective tool for tuberculosis infection diagnosis, surveillance and prevention, especially for point-of-care (POC) test and field deployment in source-limited regions.


Subject(s)
COVID-19 , Mycobacterium tuberculosis , Tuberculosis , Humans , Mycobacterium tuberculosis/genetics , CRISPR-Cas Systems , Pandemics , Sensitivity and Specificity , COVID-19/genetics , Tuberculosis/microbiology
2.
PLoS Pathog ; 19(3): e1011297, 2023 03.
Article in English | MEDLINE | ID: covidwho-2311522

ABSTRACT

Macrophages are a first line of defense against pathogens. However, certain invading microbes modify macrophage responses to promote their own survival and growth. Mycobacterium tuberculosis (M.tb) is a human-adapted intracellular pathogen that exploits macrophages as an intracellular niche. It was previously reported that M.tb rapidly activates cAMP Response Element Binding Protein (CREB), a transcription factor that regulates diverse cellular responses in macrophages. However, the mechanism(s) underlying CREB activation and its downstream roles in human macrophage responses to M.tb are largely unknown. Herein we determined that M.tb-induced CREB activation is dependent on signaling through MAPK p38 in human monocyte-derived macrophages (MDMs). Using a CREB-specific inhibitor, we determined that M.tb-induced CREB activation leads to expression of immediate early genes including COX2, MCL-1, CCL8 and c-FOS, as well as inhibition of NF-kB p65 nuclear localization. These early CREB-mediated signaling events predicted that CREB inhibition would lead to enhanced macrophage control of M.tb growth, which we observed over days in culture. CREB inhibition also led to phosphorylation of RIPK3 and MLKL, hallmarks of necroptosis. However, this was unaccompanied by cell death at the time points tested. Instead, bacterial control corresponded with increased colocalization of M.tb with the late endosome/lysosome marker LAMP-1. Increased phagolysosomal fusion detected during CREB inhibition was dependent on RIPK3-induced pMLKL, indicating that M.tb-induced CREB signaling limits phagolysosomal fusion through inhibition of the necroptotic signaling pathway. Altogether, our data show that M.tb induces CREB activation in human macrophages early post-infection to create an environment conducive to bacterial growth. Targeting certain aspects of the CREB-induced signaling pathway may represent an innovative approach for development of host-directed therapeutics to combat TB.


Subject(s)
Cyclic AMP Response Element-Binding Protein , Macrophages , Mycobacterium tuberculosis , Tuberculosis , Humans , Cyclic AMP Response Element-Binding Protein/metabolism , Macrophages/metabolism , Mycobacterium tuberculosis/genetics , Necroptosis , NF-kappa B/metabolism , Phagosomes/metabolism , Signal Transduction , Tuberculosis/metabolism , Tuberculosis/microbiology
3.
Molecules ; 28(8)2023 Apr 10.
Article in English | MEDLINE | ID: covidwho-2294072

ABSTRACT

The human immunodeficiency virus (HIV) produces the pathologic basis of acquired immunodeficiency syndrome (AIDS). An increase in the viral load in the body leads to a decline in the number of T lymphocytes, compromising the patient's immune system. Some opportunistic diseases may result, such as tuberculosis (TB), which is the most common in seropositive patients. Long-term treatment is required for HIV-TB coinfection, and cocktails of drugs for both diseases are used concomitantly. The most challenging aspects of treatment are the occurrence of drug interactions, overlapping toxicity, no adherence to treatment and cases of resistance. Recent approaches have involved using molecules that can act synergistically on two or more distinct targets. The development of multitarget molecules could overcome the disadvantages of the therapies used to treat HIV-TB coinfection. This report is the first review on using molecules with activities against HIV and Mycobacterium tuberculosis (MTB) for molecular hybridization and multitarget strategies. Here, we discuss the importance and development of multiple targets as a means of improving adherence to therapy in cases of the coexistence of these pathologies. In this context, several studies on the development of structural entities to treat HIV-TB simultaneously are discussed.


Subject(s)
Coinfection , HIV Infections , Mycobacterium tuberculosis , Tuberculosis , Humans , HIV , Antitubercular Agents/pharmacology , Antitubercular Agents/therapeutic use , Coinfection/drug therapy , Coinfection/epidemiology , Tuberculosis/complications , Tuberculosis/drug therapy , Tuberculosis/microbiology , HIV Infections/complications , HIV Infections/drug therapy
5.
Int J Mol Sci ; 24(5)2023 Mar 06.
Article in English | MEDLINE | ID: covidwho-2283654

ABSTRACT

Mycobacterium tuberculosis (Mtb), the etiologic agent of tuberculosis (TB), has killed nearly one billion people in the last two centuries. Nowadays, TB remains a major global health problem, ranking among the thirteen leading causes of death worldwide. Human TB infection spans different levels of stages: incipient, subclinical, latent and active TB, all of them with varying symptoms, microbiological characteristics, immune responses and pathologies profiles. After infection, Mtb interacts with diverse cells of both innate and adaptive immune compartments, playing a crucial role in the modulation and development of the pathology. Underlying TB clinical manifestations, individual immunological profiles can be identified in patients with active TB according to the strength of their immune responses to Mtb infection, defining diverse endotypes. Those different endotypes are regulated by a complex interaction of the patient's cellular metabolism, genetic background, epigenetics, and gene transcriptional regulation. Here, we review immunological categorizations of TB patients based on the activation of different cellular populations (both myeloid and lymphocytic subsets) and humoral mediators (such as cytokines and lipid mediators). The analysis of the participating factors that operate during active Mtb infection shaping the immunological status or immune endotypes of TB patients could contribute to the development of Host Directed Therapy.


Subject(s)
Latent Tuberculosis , Mycobacterium tuberculosis , Tuberculosis , Humans , Tuberculosis/microbiology , Mycobacterium tuberculosis/metabolism , Latent Tuberculosis/microbiology , Cytokines/metabolism
6.
BMC Microbiol ; 23(1): 7, 2023 01 09.
Article in English | MEDLINE | ID: covidwho-2196045

ABSTRACT

INTRODUCTION: Globally, the highest burden of bovine and human tuberculosis resides in Africa and Asia. Tuberculosis (TB) is the second leading single infectious killer after severe acute respiratory syndrome corona virus-2 (SARSCOV-2). Bovine TB remains a treat to wild and domesticated animals, humans and hinders international trade in endemic countries like Nigeria. We aimed at determining the prevalence of bovine and human tuberculosis, and the spoligotypes of Mycobacterium tuberculosis complex in cattle and humans in Maiduguri. METHODS: We conducted a cross sectional study on bovine and human tuberculosis in Maiduguri, Borno state. We calculated sample size using the method of Thrusfield. Lesions suggestive of TB from 160 slaughtered cattle were obtained from Maiduguri Central Abattoir. Sputum samples from humans; 82 abattoir workers and 147 suspected TB patients from hospitals/clinics were obtained. Lesions and sputum samples were cultured for the isolation of Mycobacterium spp. Positive cultures were subjected genus typing, deletion analysis and selected isolates were spoligotyped. Data was analysed using SPSS VERSION 16.0. RESULTS: Prevalence of 32.5% (52/160) was obtained in cattle. Damboa local government area (LGA), where majority of the infected animals were obtained from had 35.5% bTB prevalence. All categories analysed (breed, age, sex, body conformation and score) had P-values that were not significant (P > 0.05). Sputum culture revealed a prevalence of 3.7% (3/82) from abattoir workers and 12.2% from hospitals/clinics. A significant P-value (0.03) was obtained when positive culture from abattoir and that of hospitals/clinics were compared. Out of the 52 culture positive isolates obtained from cattle, 26 (50%) belonged to M. tuberculosis complex (MTC) and 17/26 (65.4%) were characterized as M. bovis. In humans, 7/12 (58.3%) MTC obtained were characterized as M. tuberculosis. Spoligotyping revealed SB0944 and SB1025 in cattle, while SIT838, SIT61 of LAM10_CAM and SIT1054, SIT46 of Haarlem (H) families were obtained from humans. CONCLUSIONS: Cattle in Damboa LGA need to be screened for bTB as majority of the infected animals were brought from there. Our findings revealed the presence of SB0944 and SB1025 spoligotypes from cattle in Borno state. We isolated M. tuberculosis strain of the H family mainly domiciled in Europe from humans.


Subject(s)
Mycobacterium bovis , Mycobacterium tuberculosis , Tuberculosis, Bovine , Tuberculosis , Animals , Cattle , Humans , Animals, Domestic , Cross-Sectional Studies , Nigeria/epidemiology , Prevalence , Tuberculosis/epidemiology , Tuberculosis/veterinary , Tuberculosis/microbiology , Tuberculosis, Bovine/diagnosis , Tuberculosis, Bovine/epidemiology , Tuberculosis, Bovine/microbiology
7.
Int J Mycobacteriol ; 11(4): 415-422, 2022.
Article in English | MEDLINE | ID: covidwho-2163900

ABSTRACT

Background: Recent pandemic of coronavirus SARS-CoV-2 (COVID-19) caused limitations in the country's strategies to fight against mycobacterial infections. The aim of this study was to compare the suspected tuberculosis (TB) pulmonary patients before and during the COVID-19 pandemic (January 2018-December 2021) who were referred to the National Reference TB Laboratory (NRL TB), Tehran, Iran. The mycobacterial isolated strains were identified and compared with previous data. Methods: A total of 16,899 clinical samples collected from 7041 suspected pulmonary TB patients were received from 2018 to 2021. Primary isolation of Mycobacterium isolates was done on Löwenstein-Jensen medium. Then, the DNA was extracted from acid-fast bacillus culture-positive samples and identification was performed by IS6110, Hsp65, and 16S-23S rRNA genes using polymerase chain reaction (PCR), PCR-restriction fragment length polymorphism, and nested PCR methods. Results: A total of 11679 specimens (69.1%) from 4866 suspected TB patients were collected in 2018-2019 and 5220 specimens (30.8%; from 2175 patients) in 2020-2021. Out of 11679 specimens, 2046 samples that belong to 852 patients were infected with Mycobacterium tuberculosis, and the remaining were non-TB Mycobacterium (NTM) species (n = 244) isolated from 102 patients. The cultures for 12894 specimens were either negative (76.3%) or contaminated (845/16899; 5%). A comparison of the total number of patients who were referred for diagnosis and treatment (954/666 patients, P > 0.05) showed a 30.1% reduction during the COVID-19 pandemic. Although, with these low number of patients, the significant increases of NTM species (P < 0.05) among suspected TB pulmonary patients were observed. Besides, new species of NTM, for example, Mycobacterium peregrinum and Mycobacterium montefiorense, were detected. For the past 20 years, these two species were not reported from pulmonary patients in Iran. Conclusions: During the pandemic of COVID-19, the TB diagnosis network became irregular, as a consequence, many patients could not reach the treatment center, and this could increase the circulation of mycobacterial diseases (TB and NTM). The study shows the emergence of new opportunistic NTM species also.


Subject(s)
COVID-19 , Mycobacterium Infections, Nontuberculous , Mycobacterium tuberculosis , Tuberculosis , Humans , Mycobacterium Infections, Nontuberculous/microbiology , Pandemics , COVID-19/epidemiology , SARS-CoV-2/genetics , Iran/epidemiology , Nontuberculous Mycobacteria , Tuberculosis/diagnosis , Tuberculosis/epidemiology , Tuberculosis/microbiology , RNA, Ribosomal, 16S/genetics
9.
Molecules ; 27(20)2022 Oct 17.
Article in English | MEDLINE | ID: covidwho-2071654

ABSTRACT

Mycobacterium tuberculosis (Mtb), an acid-fast bacillus that causes Tuberculosis (TB), is a pathogen that caused 1.5 million deaths in 2020. As per WHO estimates, another 4.1 million people are suffering from latent TB, either asymptomatic or not diagnosed, and the frequency of drug resistance is increasing due to intrinsically linked factors from both host and bacterium. For instance, poor access to TB diagnosis and reduced treatment in the era of the COVID-19 pandemic has resulted in more TB deaths and an 18% reduction in newly diagnosed cases of TB. Additionally, the detection of Mtb isolates exhibiting resistance to multiple drugs (MDR, XDR, and TDR) has complicated the scenario in the pathogen's favour. Moreover, the conventional methods to detect drug resistance may miss mutations, making it challenging to decide on the treatment regimen. However, owing to collaborative initiatives, the last two decades have witnessed several advancements in both the detection methods and drug discovery against drug-resistant isolates. The majority of them belong to nucleic acid detection techniques. In this review, we highlight and summarize the molecular mechanism underlying drug resistance in Mtb, the recent advancements in resistance detection methods, and the newer drugs used against drug-resistant TB.


Subject(s)
COVID-19 , Mycobacterium tuberculosis , Nucleic Acids , Tuberculosis , Humans , Antitubercular Agents/pharmacology , Antitubercular Agents/therapeutic use , Pandemics , Tuberculosis/drug therapy , Tuberculosis/epidemiology , Tuberculosis/microbiology , Drug Resistance , Drug Resistance, Multiple, Bacterial , Microbial Sensitivity Tests
10.
Microbiol Spectr ; 10(5): e0125222, 2022 Oct 26.
Article in English | MEDLINE | ID: covidwho-2029475

ABSTRACT

Tuberculosis (TB) remains one of the most important infectious diseases globally. Establishing a resistance profile from the initial TB diagnosis is a priority. Rapid molecular tests evaluate only the most common genetic variants responsible for resistance to certain drugs, and Whole Genome Sequencing (WGS) needs culture prior to next-generation sequencing (NGS), limiting their clinical value. Targeted sequencing (TS) from clinical samples avoids these drawbacks, providing a signature of genetic markers that can be associated with drug resistance and phylogeny. In this study, a proof-of-concept protocol was developed for detecting genomic variants associated with drug resistance and for the phylogenetic classification of Mycobacterium Tuberculosis (Mtb) in sputum samples. Initially, a set of Mtb reference strains from the WHO were sequenced (WGS and TS). The results from the protocol agreed >95% with WHO reported data and phenotypic drug susceptibility testing (pDST). Lineage genetics results were 100% concordant with those derived from WGS. After that, the TS protocol was applied to sputum samples from TB patients to detect resistance to first- and second-line drugs and derive phylogeny. The accuracy was >90% for all evaluated drugs, except Eto/Pto (77.8%), and 100% were phylogenetically classified. The results indicate that the described protocol, which affords the complete drug resistance profile and phylogeny of Mtb from sputum, could be useful in the clinical area, advancing toward more personalized and more effective treatments in the near future. IMPORTANCE The COVID-19 pandemic negatively affected the progress in accessing essential Tuberculosis (TB) services and reducing the burden of TB disease, resulting in a decreased detection of new cases and increased deaths. Generating molecular diagnostic tests with faster results without losing reliability is considered a priority. Specifically, developing an antimicrobial resistance profile from the initial stages of TB diagnosis is essential to ensure appropriate treatment. Currently available rapid molecular tests evaluate only the most common genetic variants responsible for resistance to certain drugs, limiting their clinical value. In this work, targeted sequencing on sputum samples from TB patients was used to identify Mycobacterium tuberculosis mutations in genes associated with drug resistance and to derive a phylogeny of the infecting strain. This protocol constitutes a proof-of-concept toward the goal of helping clinicians select a timely and appropriate treatment by providing them with actionable information beyond current molecular approaches.


Subject(s)
COVID-19 , Mycobacterium tuberculosis , Tuberculosis, Multidrug-Resistant , Tuberculosis , Humans , Sputum , Antitubercular Agents/pharmacology , Antitubercular Agents/therapeutic use , Phylogeny , Microbial Sensitivity Tests , Reproducibility of Results , Genetic Markers , Pandemics , Tuberculosis/microbiology , Drug Resistance , Tuberculosis, Multidrug-Resistant/drug therapy
11.
Molecules ; 27(16)2022 Aug 22.
Article in English | MEDLINE | ID: covidwho-2023940

ABSTRACT

Tuberculosis (TB) caused by the bacterial pathogen Mycobacterium tuberculosis (Mtb) remains a threat to mankind, with over a billion of deaths in the last two centuries. Recent advancements in science have contributed to an understanding of Mtb pathogenesis and developed effective control tools, including effective drugs to control the global pandemic. However, the emergence of drug resistant Mtb strains has seriously affected the TB eradication program around the world. There is, therefore, an urgent need to develop new drugs for TB treatment, which has grown researchers' interest in small molecule-based drug designing and development. The small molecules-based treatments hold significant potential to overcome drug resistance and even provide opportunities for multimodal therapy. In this context, various natural and synthetic flavonoids were reported for the effective treatment of TB. In this review, we have summarized the recent advancement in the understanding of Mtb pathogenesis and the importance of both natural and synthetic flavonoids against Mtb infection studied using in vitro and in silico methods. We have also included flavonoids that are able to inhibit the growth of non-tubercular mycobacterial organisms. Hence, understanding the therapeutic properties of flavonoids can be useful for the future treatment of TB.


Subject(s)
Mycobacterium tuberculosis , Tuberculosis , Antitubercular Agents/pharmacology , Antitubercular Agents/therapeutic use , Drug Delivery Systems , Flavonoids/pharmacology , Flavonoids/therapeutic use , Humans , Tuberculosis/drug therapy , Tuberculosis/microbiology
12.
Int J Mol Sci ; 23(15)2022 Aug 01.
Article in English | MEDLINE | ID: covidwho-1994084

ABSTRACT

Tuberculosis remains a major threat to global public health, with more than 1.5 million deaths recorded in 2020. Improved interventions against tuberculosis are urgently needed, but there are still gaps in our knowledge of the host-pathogen interaction that need to be filled, especially at the site of infection. With a long history of infection in humans, Mycobacterium tuberculosis (Mtb) has evolved to be able to exploit the microenvironment of the infection site to survive and grow. The immune cells are not only reliant on immune signalling to mount an effective response to Mtb invasion but can also be orchestrated by their metabolic state. Cellular metabolism was often overlooked in the past but growing evidence of its importance in the functions of immune cells suggests that it can no longer be ignored. This review aims to gain a better understanding of mucosal immunometabolism of resident effector cells, such as alveolar macrophages and mucosal-associated invariant T cells (MAIT cells), in response to Mtb infection and how Mtb manipulates them for its survival and growth, which could address our knowledge gaps while opening up new questions, and potentially be applied for future vaccination and therapeutic strategies.


Subject(s)
Mucosal-Associated Invariant T Cells , Mycobacterium tuberculosis , Tuberculosis , Host-Pathogen Interactions , Humans , Immunity, Innate , Tuberculosis/microbiology
13.
Front Immunol ; 13: 870768, 2022.
Article in English | MEDLINE | ID: covidwho-1957155

ABSTRACT

Tuberculosis (TB), considered an ancient disease, is still killing one person every 21 seconds. Diagnosis of Mycobacterium tuberculosis (M.tb) still has many challenges, especially in low and middle-income countries with high burden disease rates. Over the last two decades, the amount of drug-resistant (DR)-TB cases has been increasing, from mono-resistant (mainly for isoniazid or rifampicin resistance) to extremely drug resistant TB. DR-TB is problematic to diagnose and treat, and thus, needs more resources to manage it. Together with+ TB clinical symptoms, phenotypic and genotypic diagnosis of TB includes a series of tests that can be used on different specimens to determine if a person has TB, as well as if the M.tb strain+ causing the disease is drug susceptible or resistant. Here, we review and discuss advantages and disadvantages of phenotypic vs. genotypic drug susceptibility testing for DR-TB, advances in TB immunodiagnostics, and propose a call to improve deployable and low-cost TB diagnostic tests to control the DR-TB burden, especially in light of the increase of the global burden of bacterial antimicrobial resistance, and the potentially long term impact of the coronavirus disease 2019 (COVID-19) disruption on TB programs.


Subject(s)
COVID-19 , Mycobacterium tuberculosis , Tuberculosis, Multidrug-Resistant , Tuberculosis , Antitubercular Agents/pharmacology , Antitubercular Agents/therapeutic use , COVID-19/diagnosis , Humans , Microbial Sensitivity Tests , Mycobacterium tuberculosis/genetics , Tuberculosis/diagnosis , Tuberculosis/drug therapy , Tuberculosis/microbiology , Tuberculosis, Multidrug-Resistant/diagnosis , Tuberculosis, Multidrug-Resistant/drug therapy , Tuberculosis, Multidrug-Resistant/microbiology
14.
Infect Genet Evol ; 103: 105343, 2022 09.
Article in English | MEDLINE | ID: covidwho-1956268

ABSTRACT

The dramatic change in global health imposed by the Covid-19 pandemic has also impacted TB control. The TB incidence decreased dramatically not because of the improved situation but due to undertesting, reduced resources, and ultimately, substantially reduced detection rate. We hypothesized that multiple and partly counteracting factors could influence changes in the local Mycobacterium tuberculosis population. To test this hypothesis, we analyzed M. tuberculosis isolates collected in Western Siberia, Russia, before and during the Covid-19 pandemic. A total of 269 M. tuberculosis isolates from patients admitted at referral clinics were studied. The pre-pandemic and pandemic collections included 179 and 90 isolates, respectively. Based on genotyping, both pre-pandemic and pandemic samples are heavily dominated by the Beijing genotype isolates (95% and 88%) that were mostly MDR (80 and 68%). The high proportion of MDR isolates is due to the specific features of the studied collections biased towards patients with severe TB admitted at the National referral center in Novosibirsk. While no dramatic change was observed in the M. tuberculosis population structure in the survey area in Western Siberia during the Covid-19 pandemic in 2020-2021 compared to the pre-pandemic collection, still we note a certain decrease of the Beijing genotype and an increase in the proportion and diversity of the non-Beijing isolates. However, the transmissible and MDR Beijing B0/W148 did not increase its prevalence rate during the pandemic. More generally, the high prevalence rate of the Beijing genotype and its strong association with MDR both before and during the pandemic are alarming features of this region in Western Siberia, Russia.


Subject(s)
COVID-19 , Mycobacterium tuberculosis , Tuberculosis, Multidrug-Resistant , Tuberculosis , Antitubercular Agents/pharmacology , COVID-19/epidemiology , Drug Resistance, Multiple, Bacterial/genetics , Genotype , Humans , Pandemics , Referral and Consultation , Russia/epidemiology , Siberia/epidemiology , Tuberculosis/microbiology , Tuberculosis, Multidrug-Resistant/microbiology
15.
Int J Mol Sci ; 23(13)2022 Jun 29.
Article in English | MEDLINE | ID: covidwho-1911406

ABSTRACT

Tuberculosis (TB), caused by the bacillus Mycobacterium tuberculosis (Mtb), remains a leading cause of death by infectious disease, overshadowed only recently by the COVID-19 pandemic [...].


Subject(s)
COVID-19 , Mycobacterium tuberculosis , Tuberculosis , Humans , Pandemics , Tuberculosis/microbiology
16.
PLoS Pathog ; 18(5): e1010490, 2022 05.
Article in English | MEDLINE | ID: covidwho-1902645

ABSTRACT

Tuberculosis (TB), one of the deadliest threats to human health, is mainly caused by 2 highly related and human-adapted bacteria broadly known as Mycobacterium tuberculosis and Mycobacterium africanum. Whereas M. tuberculosis is widely spread, M. africanum is restricted to West Africa, where it remains a significant cause of tuberculosis. Although several differences have been identified between these 2 pathogens, M. africanum remains a lot less studied than M. tuberculosis. Here, we discuss the genetic, phenotypic, and clinical similarities and differences between strains of M. tuberculosis and M. africanum. We also discuss our current knowledge on the immune response to M. africanum and how it possibly articulates with distinct disease progression and with the geographical restriction attributed to this pathogen. Understanding the functional impact of the diversity existing in TB-causing bacteria, as well as incorporating this diversity in TB research, will contribute to the development of better, more specific approaches to tackle TB.


Subject(s)
Mycobacterium tuberculosis , Tuberculosis , Africa, Western , Geography , Humans , Mycobacterium tuberculosis/genetics , Tuberculosis/microbiology
17.
Int J Mol Sci ; 23(11)2022 May 27.
Article in English | MEDLINE | ID: covidwho-1892895

ABSTRACT

Identification of alternative attenuation targets of Mycobacterium tuberculosis (Mtb) is pivotal for designing new candidates for live attenuated anti-tuberculosis (TB) vaccines. In this context, the CtpF P-type ATPase of Mtb is an interesting target; specifically, this plasma membrane enzyme is involved in calcium transporting and response to oxidative stress. We found that a mutant of MtbH37Rv lacking ctpF expression (MtbΔctpF) displayed impaired proliferation in mouse alveolar macrophages (MH-S) during in vitro infection. Further, the levels of tumor necrosis factor and interferon-gamma in MH-S cells infected with MtbΔctpF were similar to those of cells infected with the parental strain, suggesting preservation of the immunogenic capacity. In addition, BALB/c mice infected with Mtb∆ctpF showed median survival times of 84 days, while mice infected with MtbH37Rv survived 59 days, suggesting reduced virulence of the mutant strain. Interestingly, the expression levels of ctpF in a mouse model of latent TB were significantly higher than in a mouse model of progressive TB, indicating that ctpF is involved in Mtb persistence in the dormancy state. Finally, the possibility of complementary mechanisms that counteract deficiencies in Ca2+ transport mediated by P-type ATPases is suggested. Altogether, our results demonstrate that CtpF could be a potential target for Mtb attenuation.


Subject(s)
Mycobacterium tuberculosis , Tuberculosis , Animals , Calcium , Calcium-Transporting ATPases , Cell Membrane/pathology , Mice , Tuberculosis/microbiology , Virulence/genetics
18.
Braz J Microbiol ; 53(2): 633-639, 2022 Jun.
Article in English | MEDLINE | ID: covidwho-1872828

ABSTRACT

Tuberculosis (TB) and COVID-19 affect the lungs and are transmitted mainly by aerosols or particles of saliva from infected persons. Clinical similarities between diseases can affect correct diagnosis. Individuals belonging to the population deprived of liberty (PDL) are at increased risk of contagion due to precarious sanitary conditions and overcrowded environments. A variety of specimens may be suitable for the diagnosis of COVID-19, using molecular diagnostic techniques; however, there is little data on the analysis of sputum samples with the Xpert Xpress SARS-CoV-2® for the diagnosis of COVID-19, especially in this population group. The present study reports a case of TB and COVID-19 co-infection detected in sputum from an individual belonging to the PDL. For the detection, it used the GeneXpert platform (Cepheid, USA). Mycobacterium tuberculosis complex (MTC) was detected using the Xpert MTB/RIF Ultra® cartridge and SARS-CoV-2 was detected using the Xpert Xpress SARS-CoV-2® cartridge. The genes IS6110 and IS1081 were detected within 80 min indicating the presence of MTC, with no mutations related to resistance to rifampicin. The SARS-CoV-2 E and N2 genes were detected within 45 min. The result was confirmed by RT-qPCR with detection of E, N, and RdRP/S genes in the sputum and nasopharyngeal (NP) specimens. Rapid diagnoses that allow the identification and differentiation of such diseases are important for adequate epidemiological surveillance, isolation of infected individuals, and interruption of the transmission chain. Using the GeneXpert platform, specimens can be tested as soon as they are received, without the need for prior preparation. The US Food and Drug Administration has issued emergency authorization for the use of the Cepheid Xpert Xpress SARS-CoV-2 for the rapid detection of SARS-CoV-2 using specimens from a NP or nasal wash/aspirate. The case presented here gains an innovation with the use of the sputum to COVID-19 diagnosis.


Subject(s)
COVID-19 , Coinfection , Mycobacterium tuberculosis , Tuberculosis , COVID-19/diagnosis , COVID-19 Testing , Coinfection/diagnosis , Humans , Molecular Diagnostic Techniques/methods , Mycobacterium tuberculosis/genetics , Rifampin , SARS-CoV-2/genetics , Sensitivity and Specificity , Sputum/microbiology , Tuberculosis/diagnosis , Tuberculosis/microbiology
19.
Int J Mol Sci ; 23(7)2022 Mar 23.
Article in English | MEDLINE | ID: covidwho-1785727

ABSTRACT

The field of immunometabolism seeks to decipher the complex interplay between the immune system and the associated metabolic pathways. The role of small molecules that can target specific metabolic pathways and subsequently alter the immune landscape provides a desirable platform for new therapeutic interventions. Immunotherapeutic targeting of suppressive cell populations, such as myeloid-derived suppressor cells (MDSC), by small molecules has shown promise in pathologies such as cancer and support testing of similar host-directed therapeutic approaches in MDSC-inducing conditions such as tuberculosis (TB). MDSC exhibit a remarkable ability to suppress T-cell responses in those with TB disease. In tumors, MDSC exhibit considerable plasticity and can undergo metabolic reprogramming from glycolysis to fatty acid oxidation (FAO) and oxidative phosphorylation (OXPHOS) to facilitate their immunosuppressive functions. In this review we look at the role of MDSC during M. tb infection and how their metabolic reprogramming aids in the exacerbation of active disease and highlight the possible MDSC-targeted metabolic pathways utilized during M. tb infection, suggesting ways to manipulate these cells in search of novel insights for anti-TB therapies.


Subject(s)
Mycobacterium tuberculosis , Myeloid-Derived Suppressor Cells , Neoplasms , Tuberculosis , Biology , Humans , Neoplasms/metabolism , Tuberculosis/microbiology
20.
PLoS One ; 17(2): e0262734, 2022.
Article in English | MEDLINE | ID: covidwho-1699186

ABSTRACT

BACKGROUND AND OBJECTIVE: Tuberculosis (Tuberculosis, TB) is a public health problem in China, which not only endangers the population's health but also affects economic and social development. It requires an accurate prediction analysis to help to make policymakers with early warning and provide effective precautionary measures. In this study, ARIMA, GM(1,1), and LSTM models were constructed and compared, respectively. The results showed that the LSTM was the optimal model, which can be achieved satisfactory performance for TB cases predictions in mainland China. METHODS: The data of tuberculosis cases in mainland China were extracted from the National Health Commission of the People's Republic of China website. According to the TB data characteristics and the sample requirements, we created the ARIMA, GM(1,1), and LSTM models, which can make predictions for the prevalence trend of TB. The mean absolute error (MAE), root mean square error (RMSE), and mean absolute percentage error (MAPE) were applied to evaluate the effects of model fitting predicting accuracy. RESULTS: There were 3,021,995 tuberculosis cases in mainland China from January 2018 to December 2020. And the overall TB cases in mainland China take on a downtrend trend. We established ARIMA, GM(1,1), and LSTM models, respectively. The optimal ARIMA model is the ARIMA (0,1,0) × (0,1,0)12. The equation for GM(1,1) model was X(k+1) = -10057053.55e(-0.01k) + 10153178.55 the Mean square deviation ratio C value was 0.49, and the Small probability of error P was 0.94. LSTM model consists of an input layer, a hidden layer and an output layer, the parameters of epochs, learning rating are 60, 0.01, respectively. The MAE, RMSE, and MAPE values of LSTM model were smaller than that of GM(1,1) and ARIMA models. CONCLUSIONS: Our findings showed that the LSTM model was the optimal model, which has a higher accuracy performance than that of ARIMA and GM (1,1) models. Its prediction results can act as a predictive tool for TB prevention measures in mainland China.


Subject(s)
Deep Learning , Models, Statistical , Mycobacterium tuberculosis , Seasons , Tuberculosis/epidemiology , China/epidemiology , Forecasting/methods , Humans , Incidence , Prevalence , Probability , Prognosis , Public Health , Tuberculosis/microbiology
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