RESUMEN

Introduction: tuberculosis remains a major public health problem, with continuing high levels of prevalence, and mortality. In Niger, the incidence of tuberculosis remains high. This study aims to investigate the epidemiology of pulmonary tuberculosis at the National Anti-Tuberculosis Center of Niamey in Niger. Methods: this study used a quantitative approach with a retrospective and descriptive design. Data were obtained from positive pulmonary tuberculosis cases detected by microscopy on Ziehl-Neelsen stained sputum at the National Anti-Tuberculosis Center (NATC) in Niamey, Niger covered the period between June 2017 and January 2020. 955 pulmonary TB patients were recorded whose diagnosis was based either on clinical-radiological arguments (thus negative microscopy) or positive microscopy. This form was used to collect data recorded in the clinical case registers, registers, and Excel files of the GeneXpert platform of the NATC laboratory. Results: eighty-nine-point eleven percent (89.11%) of the patients were microscopy-positive. Among the study population, men were the most affected by tuberculosis with 80.03%. The 25-34 age group, representing 23.77%, was the most affected. 6.93% of patients were co-infected with tuberculosis and HIV. All patients were put on treatment, with a therapeutic success rate of 72.38% and a therapeutic failure rate of 10.95%. Among the cases of therapeutic failure, 80.90% had Mycobacterium tuberculosis complex detected and 27.14% were resistant to Rifampicin. Conclusion: Niger continues to have a tuberculosis epidemic which requires monitoring. Improving the diagnostic system for more effective management of the disease is important for appropriate diagnosis and treatment.

Asunto(s)

Antituberculosos , Mycobacterium tuberculosis , Tuberculosis Pulmonar , Humanos , Estudios Retrospectivos , Masculino , Niger/epidemiología , Femenino , Adulto , Tuberculosis Pulmonar/tratamiento farmacológico , Tuberculosis Pulmonar/epidemiología , Tuberculosis Pulmonar/diagnóstico , Antituberculosos/farmacología , Antituberculosos/administración & dosificación , Adulto Joven , Persona de Mediana Edad , Mycobacterium tuberculosis/aislamiento & purificación , Mycobacterium tuberculosis/efectos de los fármacos , Adolescente , Resultado del Tratamiento , Niño , Infecciones por VIH/epidemiología , Infecciones por VIH/tratamiento farmacológico , Preescolar , Anciano , Tuberculosis Resistente a Múltiples Medicamentos/epidemiología , Tuberculosis Resistente a Múltiples Medicamentos/tratamiento farmacológico , Tuberculosis Resistente a Múltiples Medicamentos/diagnóstico , Esputo/microbiología , Prevalencia , Coinfección/epidemiología , Coinfección/tratamiento farmacológico , Lactante , Incidencia

RESUMEN

The Mycobacterium cell wall is a capsule-like structure comprising of various layers of biomolecules such as mycolic acid, peptidoglycans, and arabinogalactans, which provide the Mycobacteria a sort of cellular shield. Drugs like isoniazid, ethambutol, cycloserine, delamanid, and pretomanid inhibit cell wall synthesis by inhibiting one or the other enzymes involved in cell wall synthesis. Many enzymes present across these layers serve as potential targets for the design and development of newer anti-TB drugs. Some of these targets are currently being exploited as the most druggable targets like DprE1, InhA, and MmpL3. Many of the anti-TB agents present in clinical trials inhibit cell wall synthesis. The present article covers a systematic perspective of developing cell wall inhibitors targeting various enzymes involved in cell wall biosynthesis as potential drug candidates for treating Mtb infection.

Asunto(s)

Antituberculosos , Proteínas Bacterianas , Pared Celular , Mycobacterium tuberculosis , Pared Celular/metabolismo , Pared Celular/efectos de los fármacos , Antituberculosos/farmacología , Antituberculosos/química , Mycobacterium tuberculosis/efectos de los fármacos , Mycobacterium tuberculosis/metabolismo , Humanos , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/antagonistas & inhibidores , Tuberculosis/tratamiento farmacológico , Oxidorreductasas/metabolismo , Oxidorreductasas/antagonistas & inhibidores , Ácidos Micólicos/metabolismo , Oxidorreductasas de Alcohol , Proteínas de Transporte de Membrana

RESUMEN

BACKGROUNDS: Mycobacterium tuberculosis (Mtb), the pathogen responsible for tuberculosis, secretes a multitude of proteins that modulate the host's immune response to ensure its own persistence. The region of difference (RD) genes encoding proteins play key roles in TB immunity and pathogenesis. Nevertheless, the roles of the majority of RD-encoded proteins remain to be elucidated. OBJECTS: To elucidate the role of Rv2652c located in RD13 in Mtb on bacterial growth, bacterial survival, and host immune response. METHODS: We constructed the strain MS_Rv2652c which over-expresses Mtb RD-encoding protein Rv2652c in M. smegmatis (MS), and compared it with the wild strain in the bacterial growth, bacterial survival, virulence of Rv2652c, and determined the effect of MS_Rv2652c on host immune response in macrophages. RESULTS: Rv2652c protein is located at cell wall of MS_Rv2652c strain and also an integral component of the Mtb H37Rv cell wall. Rv2652c can enhance the resistance of recombinant MS to various stressors. Moreover, Rv2652c inhibits host proinflammatory responses via modulation of the NF-κB pathway, thereby promoting Mtb survival in vitro and in vivo. CONCLUSION: Our data suggest that cell wall protein Rv2652c plays an important role in creating a favorable environment for bacterial survival by modulating host signals and could be established as a potential TB drug target.

Asunto(s)

Proteínas Bacterianas , Macrófagos , Mycobacterium tuberculosis , Mycobacterium tuberculosis/inmunología , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/inmunología , Animales , Ratones , Macrófagos/inmunología , Macrófagos/microbiología , Macrófagos/metabolismo , Tuberculosis/inmunología , Tuberculosis/microbiología , Humanos , Interacciones Huésped-Patógeno/inmunología , Virulencia , Mycobacterium smegmatis/inmunología , Viabilidad Microbiana/inmunología , FN-kappa B/metabolismo , Ratones Endogámicos C57BL , Pared Celular/inmunología , Pared Celular/metabolismo

RESUMEN

Tuberculosis(TB) of the Central nervous system (CNS) is a rare and highly destructive disease. The emergence of drug resistance has increased treatment difficulty, leaving the Bacillus Calmette-Guérin (BCG) vaccine as the only licensed preventative immunization available. This study focused on identifying the epitopes of PknD (Rv0931c) and Rv0986 from Mycobacterium tuberculosis(Mtb) strain H37Rv using an in silico method. The goal was to develop a therapeutic mRNA vaccine for preventing CNS TB. The vaccine was designed to be non-allergenic, non-toxic, and highly antigenic. Codon optimization was performed to ensure effective translation in the human host. Additionally, the secondary and tertiary structures of the vaccine were predicted, and molecular docking with TLR-4 was carried out. A molecular dynamics simulation confirmed the stability of the complex. The results indicate that the vaccine structure shows effectiveness. Overall, the constructed vaccine exhibits ideal physicochemical properties, immune response, and stability, laying a theoretical foundation for future laboratory experiments.

Asunto(s)

Simulación por Computador , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Mycobacterium tuberculosis , Tuberculosis del Sistema Nervioso Central , Humanos , Mycobacterium tuberculosis/inmunología , Tuberculosis del Sistema Nervioso Central/prevención & control , Tuberculosis del Sistema Nervioso Central/inmunología , Vacunas contra la Tuberculosis/inmunología , Epítopos/inmunología , Epítopos/química , Vacunas de ARNm , Vacunas Sintéticas/inmunología

RESUMEN

BACKGROUND: Rifampicin resistant tuberculosis remains a global health problem with almost half a million new cases annually. In high-income countries patients empirically start a standardized treatment regimen, followed by an individualized regimen guided by drug susceptibility test (DST) results. In most settings, DST information is not available or is limited to isoniazid and fluoroquinolones. Whole genome sequencing could more accurately guide individualized treatment as the full drug resistance profile is obtained with a single test. Whole genome sequencing has not reached its full potential for patient care, in part due to the complexity of translating a resistance profile into the most effective individualized regimen. METHODS: We developed a treatment recommender clinical decision support system (CDSS) and an accompanying web application for user-friendly recommendation of the optimal individualized treatment regimen to a clinician. RESULTS: Following expert stakeholder meetings and literature review, nine drug features and 14 treatment regimen features were identified and quantified. Using machine learning, a model was developed to predict the optimal treatment regimen based on a training set of 3895 treatment regimen-expert feedback pairs. The acceptability of the treatment recommender CDSS was assessed as part of a clinical trial and in a routine care setting. Within the clinical trial setting, all patients received the CDSS recommended treatment. In 8 of 20 cases, the initial recommendation was recomputed because of stock out, clinical contra-indication or toxicity. In routine care setting, physicians rejected the treatment recommendation in 7 out of 15 cases because it deviated from the national TB treatment guidelines. A survey indicated that the treatment recommender CDSS is easy to use and useful in clinical practice but requires digital infrastructure support and training. CONCLUSIONS: Our findings suggest that global implementation of the novel treatment recommender CDSS holds the potential to improve treatment outcomes of patients with RR-TB, especially those with 'difficult-to-treat' forms of RR-TB.

Asunto(s)

Antituberculosos , Sistemas de Apoyo a Decisiones Clínicas , Aprendizaje Automático , Rifampin , Tuberculosis Resistente a Múltiples Medicamentos , Humanos , Rifampin/uso terapéutico , Tuberculosis Resistente a Múltiples Medicamentos/tratamiento farmacológico , Antituberculosos/uso terapéutico , Antituberculosos/administración & dosificación , Mycobacterium tuberculosis/efectos de los fármacos , Medicina de Precisión/métodos , Pruebas de Sensibilidad Microbiana , Masculino , Femenino , Adulto

RESUMEN

Culturing and genomic sequencing of Mycobacterium tuberculosis (MTB) from tuberculosis (TB) cases is the basis for many research and clinical applications. The alternative, culture-free sequencing from diagnostic samples, is promising but poses challenges to obtain and analyse the MTB genome. Paradoxically, culture is assumed to impose a diversity bottleneck, which, if true, would entail unexplored consequences. To unravel this paradox we generate high-quality genomes of sputum-culture pairs from two different settings after developing a workflow for sequencing from sputum and a tailored bioinformatics analysis. Careful downstream comparisons reveal sources of sputum-culture incongruences due to false positive/negative variation associated with factors like low input MTB DNA or variable genomic depths. After accounting for these factors, contrary to the bottleneck dogma, we identify a 97% variant agreement within sputum-culture pairs, with a high correlation also in the variants' frequency (0.98). The combined analysis from five different settings and more than 100 available samples shows that our results can be extrapolated to different TB epidemic scenarios, demonstrating that for the cases tested culture accurately mirrors clinical samples.

Asunto(s)

Variación Genética , Mycobacterium tuberculosis , Esputo , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/aislamiento & purificación , Esputo/microbiología , Humanos , Tuberculosis/microbiología , Tuberculosis/diagnóstico , Genoma Bacteriano , ADN Bacteriano/genética , Tuberculosis Pulmonar/microbiología , Tuberculosis Pulmonar/diagnóstico

RESUMEN

The recA gene, encoding Recombinase A (RecA) is one of three Mycobacterium tuberculosis (Mtb) genes encoding an in-frame intervening protein sequence (intein) that must splice out of precursor host protein to produce functional protein. Ongoing debate about whether inteins function solely as selfish genetic elements or benefit their host cells requires understanding of interplay between inteins and their hosts. We measured environmental effects on native RecA intein splicing within Mtb using a combination of western blots and promoter reporter assays. RecA splicing was stimulated in bacteria exposed to DNA damaging agents or by treatment with copper in hypoxic, but not normoxic, conditions. Spliced RecA was processed by the Mtb proteasome, while free intein was degraded efficiently by other unknown mechanisms. Unspliced precursor protein was not observed within Mtb despite its accumulation during ectopic expression of Mtb recA within E. coli. Surprisingly, Mtb produced free N-extein in some conditions, and ectopic expression of Mtb N-extein activated LexA in E. coli. These results demonstrate that the bacterial environment greatly impacts RecA splicing in Mtb, underscoring the importance of studying intein splicing in native host environments and raising the exciting possibility of intein splicing as a novel regulatory mechanism in Mtb.

Asunto(s)

Proteínas Bacterianas , Escherichia coli , Inteínas , Mycobacterium tuberculosis , Empalme de Proteína , Rec A Recombinasas , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/metabolismo , Rec A Recombinasas/metabolismo , Rec A Recombinasas/genética , Inteínas/genética , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Exteínas/genética , Daño del ADN , Complejo de la Endopetidasa Proteasomal/metabolismo , Complejo de la Endopetidasa Proteasomal/genética , Regulación Bacteriana de la Expresión Génica , Regiones Promotoras Genéticas , Serina Endopeptidasas

RESUMEN

Drug-resistant Tuberculosis (TB) is a global public health problem. Resistance to rifampicin, the most effective drug for TB treatment, is a major growing concern. The etiological agent, Mycobacterium tuberculosis (Mtb), has a cluster of ATP-binding cassette (ABC) transporters which are responsible for drug resistance through active export. Here, we describe studies characterizing Mtb Rv1217c-1218c as an ABC transporter that can mediate mycobacterial resistance to rifampicin and have determined the cryo-electron microscopy structures of Rv1217c-1218c. The structures show Rv1217c-1218c has a type V exporter fold. In the absence of ATP, Rv1217c-1218c forms a periplasmic gate by two juxtaposed-membrane helices from each transmembrane domain (TMD), while the nucleotide-binding domains (NBDs) form a partially closed dimer which is held together by four salt-bridges. Adenylyl-imidodiphosphate (AMPPNP) binding induces a structural change where the NBDs become further closed to each other, which downstream translates to a closed conformation for the TMDs. AMPPNP binding results in the collapse of the outer leaflet cavity and the opening of the periplasmic gate, which was proposed to play a role in substrate export. The rifampicin-bound structure shows a hydrophobic and periplasm-facing cavity is involved in rifampicin binding. Phospholipid molecules are observed in all determined structures and form an integral part of the Rv1217c-1218c transporter system. Our results provide a structural basis for a mycobacterial ABC exporter that mediates rifampicin resistance, which can lead to different insights into combating rifampicin resistance.

Asunto(s)

Transportadoras de Casetes de Unión a ATP , Proteínas Bacterianas , Microscopía por Crioelectrón , Farmacorresistencia Bacteriana , Mycobacterium tuberculosis , Rifampin , Rifampin/farmacología , Rifampin/metabolismo , Transportadoras de Casetes de Unión a ATP/metabolismo , Transportadoras de Casetes de Unión a ATP/química , Transportadoras de Casetes de Unión a ATP/ultraestructura , Transportadoras de Casetes de Unión a ATP/genética , Mycobacterium tuberculosis/metabolismo , Mycobacterium tuberculosis/efectos de los fármacos , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/química , Proteínas Bacterianas/ultraestructura , Proteínas Bacterianas/genética , Modelos Moleculares , Adenilil Imidodifosfato/metabolismo

RESUMEN

Mycobacterium tuberculosis (Mtb), which causes tuberculosis (TB), is still a major global health problem. According to the World Health Organization (WHO), TB still causes more deaths worldwide than any other infectious agent. Drug-sensitive TB is treatable using first-line drugs; treatment of multidrug-resistant (MDR) and extensively drug-resistant (XDR) TB requires second- and third-line drugs. However, due to the long duration of treatment, the noncompliance of patients with different levels of resistance of Mtb to these drugs has worsened the situation. Previously developed anti-TB drugs targeted the replication machinery, protein synthesis, and cell wall biosynthesis pathways of Mtb. Therefore, novel drugs targeting alternate pathways crucial for the survival and pathogenesis of Mtb in the human host are needed. The genome of Mtb encodes three ß-carbonic anhydrases (CAs) that are fundamental for pH homeostasis, hypoxia, survival, and pathogenesis. Recently, several studies have shown that the ß-CAs of Mtb could be inhibited both in vitro and in vivo using small chemical molecules, suggesting that these enzymes could be novel targets for developing anti-TB compounds that are devoid of resistance by Mtb. In addition, homologs of ß-CAs are absent in humans; therefore, drugs developed to target these enzymes might have minimal off-target effects. In this work, we describe the roles of ß-CAs in Mtb and discuss bioinformatics and cheminformatics tools used in development and discovery of novel inhibitors of these enzymes. In addition, we summarize the in vitro and in vivo studies demonstrating that the ß-CAs of Mtb are indeed druggable targets.

Asunto(s)

Antituberculosos , Inhibidores de Anhidrasa Carbónica , Anhidrasas Carbónicas , Mycobacterium tuberculosis , Tuberculosis , Mycobacterium tuberculosis/efectos de los fármacos , Mycobacterium tuberculosis/enzimología , Humanos , Anhidrasas Carbónicas/metabolismo , Antituberculosos/farmacología , Inhibidores de Anhidrasa Carbónica/farmacología , Inhibidores de Anhidrasa Carbónica/uso terapéutico , Tuberculosis/tratamiento farmacológico , Tuberculosis/microbiología , Animales , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/antagonistas & inhibidores , Proteínas Bacterianas/genética

RESUMEN

INTRODUCTION: The WHO estimates a gap of about 30% between the incident (10.6 million) and notified (7.5 million) cases of tuberculosis (TB). Combined with the growing recognition in prevalence surveys of the high proportion of cases identified who are asymptomatic or paucisymptomatic, these data underscore how current symptom screening approaches and use of diagnostic tests with suboptimal performance on sputum miss large numbers of cases. Thus, the development of sputum-free biomarker-based tests for diagnosis is becoming necessary, which the WHO has already identified as a priority for new TB diagnostics.The objective of this study is to evaluate a combination of exhaled breath condensate (EBC) samples and mycobacterial lipoarabinomannan (LAM) as point-of-care (POC) assays to identify TB patients. METHODS AND ANALYSIS: This prospective diagnostic accuracy study is conducted at the TB Screening and Treatment Centre of International Center for Diarrhoeal Disease Research, Bangladesh, on a cohort of adults and adolescents >11 years of age. A total of 614 individuals with presumptive pulmonary TB based on TB signs, symptoms and radiography are being recruited from 28 August 2023. Spot sputum is collected for standard reference testing (L-J culture, GeneXpert MTB/Rif, acid-fast Bacilli microscopy) to fine-tune categorisation of TB disease status for each participant, defined as (1) definite TB (at least one positive standard reference test); (2) probable TB (not microbiologically confirmed but under TB treatment); (3) possible TB (no TB treatment but signs, symptoms and radiography suggestive of TB); (4) other respiratory disease (microbiologically not confirmed and no radiography presenting abnormalities compatible with TB); and (5) unknown (no microbiological evidence with normal/no TB abnormalities with radiography). Urine and EBC specimens will be subjected to LAM POC testing and biobanked for further investigation. Statistical analyses will include an assessment of diagnostic accuracy by constructing receiver operating curves and calculating sensitivity and specificity, as well as post-test probabilities. ETHICS AND DISSEMINATION: The study protocol was approved by the Research Review Committee as well as the Ethical Review Committee of icddr,b and recorded under a protocol reference number, PR-2301. Results will be submitted to open-access peer-reviewed journals, presented at academic meetings, and shared with national and international policymaking bodies.

Asunto(s)

Pruebas Respiratorias , Lipopolisacáridos , Tuberculosis Pulmonar , Humanos , Lipopolisacáridos/análisis , Tuberculosis Pulmonar/diagnóstico , Pruebas Respiratorias/métodos , Estudios Prospectivos , Biomarcadores/análisis , Bangladesh , Adulto , Pruebas en el Punto de Atención , Sensibilidad y Especificidad , Sistemas de Atención de Punto , Masculino , Femenino , Adolescente , Mycobacterium tuberculosis/aislamiento & purificación , Esputo/microbiología

RESUMEN

Introduction: Tuberculosis (TB) remains a significant health concern in India, and its complexity is exacerbated by the rising occurrence of non-communicable diseases such as diabetes mellitus (DM). Recognizing that DM is a risk factor for active TB, the emerging comorbidity of TB and PDM (TB-PDM) presents a particular challenge. Our study focused on the impact of PDM on cytokine and chemokine profiles in patients with pulmonary tuberculosis TB) who also have PDM. Materials and methods: We measured and compared the cytokine (GM-CSF, IFN-γ, IL-1α/IL-1F1, IL-1ß/IL-1F2, IL-2, IL-4, IL-5, IL-6, IL-10, IL-12p70, IL-13, IL-17/IL-17A, IL-18/IL-1F4, TNF-α) and chemokine (CCL1, CCL2, CCL3, CCL4, CCL11, CXCL1, CXCL2, CXCL9, CXCL10, and CXCL11) levels in plasma samples of TB-PDM, only TB or only PDM using multiplex assay. Results: We observed that PDM was linked to higher mycobacterial loads in TB. Patients with coexisting TB and PDM showed elevated levels of various cytokines (including IFNγ, TNFα, IL-2, IL-17, IL-1α, IL-1ß, IL-6, IL-12, IL-18, and GM-CSF) and chemokines (such as CCL1, CCL2, CCL3, CCL4, CCL11, CXCL1, CXCL9, CXCL10, and CXCL11). Additionally, cytokines such as IL-18 and GM-CSF, along with the chemokine CCL11, were closely linked to levels of glycated hemoglobin (HbA1c), hinting at an interaction between glycemic control and immune response in TB patients with PDM. Conclusion: Our results highlight the complex interplay between metabolic disturbances, immune responses, and TB pathology in the context of PDM, particularly highlighting the impact of changes in HbA1c levels. This emphasizes the need for specialized approaches to manage and treat TB-PDM comorbidity.

Asunto(s)

Citocinas , Estado Prediabético , Tuberculosis Pulmonar , Humanos , Tuberculosis Pulmonar/inmunología , Tuberculosis Pulmonar/sangre , Citocinas/sangre , Masculino , Femenino , Adulto , Persona de Mediana Edad , Estado Prediabético/inmunología , Estado Prediabético/sangre , Quimiocinas/sangre , Biomarcadores/sangre , Mycobacterium tuberculosis/inmunología , India/epidemiología

RESUMEN

Tuberculosis remains a significant global health issue, with spinal tuberculosis being a severe form of extrapulmonary tuberculosis. Despite the high morbidity associated with spinal tuberculosis, effective and rapid diagnostic methods are limited. The aim of this study was to evaluate the diagnostic accuracy of the GeneXpert compared to other microbiological methods in diagnosing spinal tuberculosis. A systematic review and meta-analysis were conducted following the PRISMA guidelines. Six databases (PubMed, Scopus, EBSCO, EMBASE, ScienceDirect, and Cochrane Central) were searched for relevant studies as of August 31, 2023. Studies were selected based on predefined inclusion criteria, focusing on patients diagnosed with spinal tuberculosis and comparing GeneXpert to microbiological culture, acid-fast bacilli (AFB) staining, and polymerase chain reaction (PCR). Two authors independently performed data extraction and quality assessment, and the meta-analysis was conducted using Meta-DiSc 2.0. Fourteen studies comprising retrospective cohort, prospective cohort, and cross-sectional designs were included. GeneXpert demonstrated a pooled sensitivity of 92% (85-96%) and specificity of 71% (51-86%) compared to culture. AFB smear had the highest specificity at 80% (70- 88%) but the lowest sensitivity at 27% (20-35%). The PCR had sensitivity and specificity of 83% (67-92%) and 58% (31-81%), respectively. Substantial heterogeneity was noted across the studies. This study highlighted that GeneXpert had high sensitivity and moderate specificity in diagnosing spinal tuberculosis, making it an alternative to conventional methods. However, further validation through larger, interventional studies is necessary to standardize its use in clinical practice.

Asunto(s)

Mycobacterium tuberculosis , Tuberculosis de la Columna Vertebral , Humanos , Tuberculosis de la Columna Vertebral/diagnóstico , Tuberculosis de la Columna Vertebral/microbiología , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/aislamiento & purificación , Sensibilidad y Especificidad

RESUMEN

Tuberculosis (TB) is caused by infection with the bacterial pathogen Mycobacterium tuberculosis (M.tb) in the respiratory tract. There was an estimated 10.6 million people newly diagnosed with TB, and there were approximately 1.3 million deaths caused by TB in 2022. Although the global prevalence of TB has remained high for decades and is an annual leading cause of death attributed to infectious diseases, only one vaccine, Bacillus Calmette-Guérin (BCG), has been approved so far to prevent/attenuate TB disease. Correlates of protection or immunological mechanisms that are needed to control M.tb remain unknown. The protective role of antibodies after BCG vaccination has also remained largely unclear; however, recent studies have provided evidence for their involvement in protection against disease, as biomarkers for the state of infection, and as potential predictors of outcomes. Interestingly, the antibodies generated post-vaccination with BCG are linked to the activation of innate immune cascades, providing further evidence that antibody effector functions are critical for protection against respiratory pathogens such as M.tb. In this review, we aim to provide current knowledge of antibody application in TB diagnosis, prevention, and treatment. Particularly, this review will focus on 1) The role of antibodies in preventing M.tb infections through preventing Mtb adherence to epithelium, antibody-mediated phagocytosis, and antibody-mediated cellular cytotoxicity; 2) The M.tb-directed antibody response generated after vaccination and how humoral profiles with different glycosylation patterns of these antibodies are linked with protection against the disease state; and 3) How antibody-mediated immunity against M.tb can be further explored as early diagnosis biomarkers and different detection methods to combat the global M.tb burden. Broadening the paradigm of differentiated antibody profiling and antibody-based detection during TB disease progression offers new directions for diagnosis, treatment, and preventative strategies. This approach involves linking the aforementioned humoral responses with the disease state, progression, and clearance.

Asunto(s)

Anticuerpos Antibacterianos , Vacuna BCG , Mycobacterium tuberculosis , Tuberculosis , Humanos , Mycobacterium tuberculosis/inmunología , Anticuerpos Antibacterianos/inmunología , Tuberculosis/inmunología , Tuberculosis/prevención & control , Vacuna BCG/inmunología , Animales , Inmunidad Innata , Vacunación , Biomarcadores

RESUMEN

Objective: Osteoarticular tuberculosis (OATB) is one of the most common forms of extrapulmonary tuberculosis; however, limited epidemiological data are available on this public health concern worldwide, especially in developing countries. This study aimed to analyze the clinical epidemiology and drug resistance characteristics of OATB cases in Hunan province which located in South-central China. Methods: We retrospectively enrolled OATB patients with Mycobacterium tuberculosis culture positive at Hunan Chest Hospital from January 2013 through March 31, 2022. The multiple demographic, clinical variables and drug susceptibility data of the patients were collected from the hospital's electronic patient records. Descriptive statistical methods, Chi-square test and logistic regression analysis were employed as statistical methods. Results: Of the 269 OATB cases, 197 (73.23%) were males, 206 (76.85%) were farmers; patients' ages ranged from 5 to 85 years, 57 (21.19%) aged at 20-29 years old and 52 (19.33%) aged at 60-69 years old. In terms of the disease, 177 (65.80%) had spinal TB with most occurrence in lumbar vertebrae (26.02%, 70/269), multiple spinal sites (18.96%, 51/269) and thoracic vertebrae (15.24%, 41/269). Outside of the spine, OATB mainly occurred in the lower limb (13.38%, 36/269). In terms of drug resistance, 40 (14.87%) and 72 (26.77%) were resistant to rifampicin (RFP) and isoniazid (INH) respectively; 38 (14.13%) were multi-drug resistant (MDR), and a total of 78 (29.00%) isolates were drug resistant. OATB patients aged 40-49 years old (compared to those aged ≥70 years) and from the west of Hunan province, China (compared to those from the center of Hunan) were at risk for developing RR/MDR (ORs were 5.057 and 4.942, respectively; 95% CIs were 1.009-25.342 and 1.458-16.750, respectively). Conclusion: In South-central China, OATB mainly affected males, farmers and those aged 20-29 and 60-69 years old. Spinal TB is prone to occur in the lumbar and multiple spinal sites. The resistance situation of OATB was serious, and people aged 40-49 years old and patients from the west of Hunan were risk factors of RR/MDR. All these findings will help to improve the prevention, diagnosis and treatment strategies of OATB.

Asunto(s)

Antituberculosos , Mycobacterium tuberculosis , Tuberculosis Osteoarticular , Humanos , Masculino , Adulto , Persona de Mediana Edad , China/epidemiología , Femenino , Anciano , Adolescente , Niño , Estudios Retrospectivos , Tuberculosis Osteoarticular/epidemiología , Tuberculosis Osteoarticular/tratamiento farmacológico , Tuberculosis Osteoarticular/microbiología , Anciano de 80 o más Años , Mycobacterium tuberculosis/efectos de los fármacos , Mycobacterium tuberculosis/aislamiento & purificación , Preescolar , Antituberculosos/farmacología , Antituberculosos/uso terapéutico , Adulto Joven , Tuberculosis Resistente a Múltiples Medicamentos/epidemiología , Tuberculosis Resistente a Múltiples Medicamentos/tratamiento farmacológico , Tuberculosis Resistente a Múltiples Medicamentos/microbiología , Farmacorresistencia Bacteriana

RESUMEN

Background: Patients who were infected by the Human Immunodeficiency Virus (HIV) could have weakened immunity that is complicated by opportunistic infections, especially for Mycobacterium tuberculosis (MTB). Notably, the HIV-MTB co-infection will accelerate the course of disease progress and greatly increase the mortality of patients. Since the traditional diagnostic methods are time-consuming and have low sensitivity, we aim to investigate the performance of mNGS (metagenomic Next-Generation Sequencing) and mNPS (metagenomic NanoPore Sequencing) for the rapid diagnosis of tuberculosis in HIV-infected patients. Methods: The 122 HIV-infected patients were enrolled for the retrospective analysis. All of the patients underwent traditional microbiological tests, mNGS, and (or) mNPS tests. The clinical comprehensive diagnosis was used as the reference standard to compare the diagnostic performance of culture, mNGS, and mNPS on tuberculosis. We also investigate the diagnostic value of mNGS and mNPS on mixed-infection. Furthermore, the treatment adjustment directed by mNGS and mNPS was analyzed. Results: Compared with the composite reference standard, the culture showed 42.6% clinical sensitivity and 100% specificity, and the OMT(other microbiological testing) had 38.9% sensitivity and 100% specificity. The mNGS had 58.6% clinical sensitivity and 96.8% specificity, and the mNPS had 68.0% clinical sensitivity and 100% specificity. The proportion of mixed-infection cases (88.9%) in the TB group was higher than those in the non-TB group (54.8%) and the mNGS and mNPS are more competitive on mixed-infection diagnosis compared with the traditional methods. Furthermore, there are 63 patients (69.2%) and 36 patients (63.2%) achieved effective treatment after receiving the detection of mNPS and mNGS, respectively. Conclusion: Our study indicated that mNPS and mNGS have high sensitivity and specificity for TB diagnosis compared with the traditional methods, and mNPS seems to have better diagnostic performance than mNGS. Moreover, mNGS and mNPS showed apparent advantages in detecting mixed infection. The mNPS and mNGS-directed medication adjustment have effective treatment outcomes for HIV-infected patients who have lower immunity.

Asunto(s)

Coinfección , Infecciones por VIH , Secuenciación de Nucleótidos de Alto Rendimiento , Metagenómica , Mycobacterium tuberculosis , Secuenciación de Nanoporos , Sensibilidad y Especificidad , Tuberculosis , Humanos , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Masculino , Tuberculosis/diagnóstico , Tuberculosis/microbiología , Femenino , Infecciones por VIH/complicaciones , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/aislamiento & purificación , Estudios Retrospectivos , Adulto , Persona de Mediana Edad , Coinfección/diagnóstico , Coinfección/microbiología , Coinfección/virología , Secuenciación de Nanoporos/métodos , Metagenómica/métodos

RESUMEN

Introduction: Mycobacterium tuberculosis, the causative agent of human tuberculosis, poses a significant threat to global public health and imposes a considerable burden on the economy. However, existing laboratory diagnostic methods for M. tuberculosis are time-consuming and have limited sensitivity levels. Methods: The CRISPR/Cas system, commonly known as the "gene scissors", demonstrates remarkable specificity and efficient signal amplification capabilities. Enzymatic recombinase amplification (ERA) was utilized to rapidly amplify trace DNA fragments at a consistent temperature without relying on thermal cyclers. By integrating of CRISPR/Cas12a with ERA, we successfully developed an ERA-CRISPR/Cas12a detection system that enables rapid identification of M. tuberculosis. Results: The sensitivity of the ERA-CRISPR/Cas12a fluorescence and lateral flow systems was 9 copies/µL and 90 copies/µL, respectively. Simultaneously, the detection system exhibited no cross-reactivity with various of respiratory pathogens and non-tuberculosis mycobacteria, demonstrating a specificity of 100%. The positive concordance rate between the ERA-CRISPR/Cas12a fluorescence system and commercial qPCR was 100% in 60 clinical samples. Meanwhile, the lateral flow system showed a positive concordance rate of 93.8% when compared to commercial qPCR. Both methods demonstrated a negative concordance rate of 100%, and the test results can be obtained in 50 min at the earliest. Discussion: The ERA-CRISPR/Cas12a system offers a rapid, sensitive, and specific method that presents a novel approach to laboratory diagnosis of M. tuberculosis.

Asunto(s)

Sistemas CRISPR-Cas , Mycobacterium tuberculosis , Técnicas de Amplificación de Ácido Nucleico , Sensibilidad y Especificidad , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/aislamiento & purificación , Humanos , Técnicas de Amplificación de Ácido Nucleico/métodos , Tuberculosis/diagnóstico , Tuberculosis/microbiología , Recombinasas/metabolismo , Recombinasas/genética , Técnicas de Diagnóstico Molecular/métodos , Proteínas Bacterianas/genética , ADN Bacteriano/genética , Proteínas Asociadas a CRISPR/genética , Endodesoxirribonucleasas

RESUMEN

The cytokine IFNγ is a principal effector of macrophage activation and immune resistance to mycobacterial infection; however, pathogenic mycobacteria are capable of surviving in IFNγ-activated macrophages by largely unknown mechanisms. In this study, we find that pathogenic mycobacteria, including M. bovis BCG and M. tuberculosis can sense IFNγ to promote their proliferative activity and virulence phenotype. Moreover, interaction with the host intracellular environment increases the susceptibility of mycobacteria to IFNγ through upregulating expression of mmpL10, a mycobacterial IFNγ receptor, thereby facilitating IFNγ-dependent survival and growth of mycobacteria in macrophages. Transmission electron microscopy analysis reveals that IFNγ triggers the secretion of extracellular vesicles, an essential virulence strategy of intracellular mycobacteria, while proteomics identifies numerous pivotal IFNγ-induced effectors required for mycobacterial infection in macrophages. Our study suggests that sensing host IFNγ is a crucial virulence mechanism used by pathogenic mycobacteria to survive and proliferate inside macrophages.

Asunto(s)

Interferón gamma , Macrófagos , Ratones Endogámicos C57BL , Mycobacterium tuberculosis , Interferón gamma/metabolismo , Interferón gamma/inmunología , Macrófagos/microbiología , Macrófagos/metabolismo , Macrófagos/inmunología , Animales , Ratones , Mycobacterium tuberculosis/patogenicidad , Mycobacterium tuberculosis/inmunología , Mycobacterium tuberculosis/metabolismo , Mycobacterium bovis/inmunología , Mycobacterium bovis/metabolismo , Humanos , Interacciones Huésped-Patógeno/inmunología , Virulencia , Receptores de Interferón/metabolismo , Receptores de Interferón/genética , Receptor de Interferón gamma , Vesículas Extracelulares/metabolismo , Vesículas Extracelulares/inmunología , Activación de Macrófagos , Infecciones por Mycobacterium/microbiología , Infecciones por Mycobacterium/inmunología , Infecciones por Mycobacterium/metabolismo , Infecciones por Mycobacterium/patología

RESUMEN

The diagnosis of mycobacterial infections, including both the Mycobacterium tuberculosis complex (MTBC) and non-tuberculous mycobacteria (NTM), poses a significant global medical challenge. This study proposes a novel approach using immunochromatographic (IC) strip tests for the simultaneous detection of MTBC and NTM. Traditional methods for identifying mycobacteria, such as culture techniques, are hindered by delays in distinguishing between MTBC and NTM, which can affect patient care and disease control. Molecular methods, while sensitive, are resource-intensive and unable to differentiate between live and dead bacteria. In this research, we developed unique monoclonal antibodies (mAbs) against Ag85B, a mycobacterial secretory protein, and successfully implemented IC strip tests named 8B and 9B. These strips demonstrated high concordance rates with conventional methods for detecting MTBC, with positivity rates of 93.9% and 85.9%, respectively. For NTM detection, the IC strip tests achieved a 63.2% detection rate compared to culture methods, considering variations in growth rates among different NTM species. Furthermore, this study highlights a significant finding regarding the potential of MPT64 and Ag85B proteins as markers for MTBC detection. In conclusion, our breakthrough method enables rapid and accurate detection of both MTBC and NTM bacteria within the BACTEC MGIT system. This approach represents a valuable tool in clinical settings for distinguishing between MTBC and NTM infections, thereby enhancing the management and control of mycobacterial diseases. KEY POINTS: • Panel of mAbs for differentiating MTB versus NTM • IC strips for diagnosing MTBC and NTM after the BACTEC MGIT • Combined detection of MTP64 and Ag85B enhances diagnostic accuracy.

Asunto(s)

Anticuerpos Monoclonales , Antígenos Bacterianos , Proteínas Bacterianas , Mycobacterium tuberculosis , Micobacterias no Tuberculosas , Tuberculosis , Mycobacterium tuberculosis/crecimiento & desarrollo , Mycobacterium tuberculosis/aislamiento & purificación , Mycobacterium tuberculosis/genética , Anticuerpos Monoclonales/inmunología , Humanos , Micobacterias no Tuberculosas/aislamiento & purificación , Micobacterias no Tuberculosas/clasificación , Micobacterias no Tuberculosas/crecimiento & desarrollo , Antígenos Bacterianos/análisis , Antígenos Bacterianos/inmunología , Tuberculosis/diagnóstico , Tuberculosis/microbiología , Proteínas Bacterianas/genética , Cromatografía de Afinidad/métodos , Sensibilidad y Especificidad , Infecciones por Mycobacterium no Tuberculosas/diagnóstico , Infecciones por Mycobacterium no Tuberculosas/microbiología , Aciltransferasas , Anticuerpos Antibacterianos/inmunología

RESUMEN

Tuberculosis is a global public health concern. Earlier reports suggested the emergence of high rates of drug resistant tuberculosis in Egypt. This study included 102 isolates of Mycobacterium tuberculosis collected from two reference laboratories in Cairo and Alexandria. All clinical isolates were sub-cultured on Löwenstein-Jensen medium and analyzed using both BD BACTEC MGIT 960 SIRE Kit and standard diffusion disk assays to identify the antibiotic sensitivity profile. Extracted genomic DNA was subjected to whole genome sequencing (WGS) using Illumina platform. Isolates that belong to lineage 4 represented > 80%, while lineage 3 represented only 11% of the isolates. The percentage of drug resistance for the streptomycin, isoniazid, rifampicin and ethambutol were 31.0, 17.2, 19.5 and 20.7, respectively. Nearly 47.1% of the isolates were sensitive to the four anti-tuberculous drugs, while only one isolate was resistant to all four drugs. In addition, several new and known mutations were identified by WGS. High rates of drug resistance and new mutations were identified in our isolates. Tuberculosis control measures should focus on the spread of mono (S, I, R, E)- and double (S, E)-drug resistant strains present at higher rates throughout the whole Nile Delta, Egypt.

Asunto(s)

Antituberculosos , Pruebas de Sensibilidad Microbiana , Mycobacterium tuberculosis , Tuberculosis Resistente a Múltiples Medicamentos , Secuenciación Completa del Genoma , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/efectos de los fármacos , Mycobacterium tuberculosis/aislamiento & purificación , Egipto/epidemiología , Humanos , Antituberculosos/farmacología , Secuenciación Completa del Genoma/métodos , Tuberculosis Resistente a Múltiples Medicamentos/microbiología , Tuberculosis Resistente a Múltiples Medicamentos/epidemiología , Mutación , Adulto , Genoma Bacteriano , Masculino , Femenino , Farmacorresistencia Bacteriana/genética , Farmacorresistencia Bacteriana Múltiple/genética , Isoniazida/farmacología , Variación Genética , Persona de Mediana Edad , Estreptomicina/farmacología

RESUMEN

The aim of this study was to explore the related factors linked to the development and infectivity of tuberculosis. This was achieved by comparing the clinical characteristics of patients with pulmonary tuberculosis (TB) who tested positive in smear Mycobacterium tuberculosis tests with this who tested negative in smear mycobacterium tests but positive in sputum Gene Xpert tests. We gathered clinical data of 1612 recently hospitalized patients diagnosed with pulmonary tuberculosis who tested positive either in sputum Gene-Xpert test or sputum smear Mycobacterium tuberculosis tests. The data was collected from January 1, 2018 to August 5, 2023, at Sichuan Provincial People's Hospital. We conducted separately analyzes and comparisons of the clinical characteristics between the two groups of patients, aiming to discussed the related factors influencing the development and infectivity of tuberculosis. In comparison to the GeneXpert positive group, the sputum smear positive group exhibited a higher proportion of elderly patients (aged 75-89) and individuals classified as underweight (BMI < 18.5 kg/m2). Furthermore, this group was more prone to experiencing symptoms such as weight loss, coughing and sputum production, hemoptysis, shortness of breath, and difficulty breathing. Moreover, they are also more likely to develop extrapulmonary tuberculosis, such as tuberculous meningitis, tuberculous pleurisy, and tuberculous peritonitis. These clinical features, when present, not only increase the likelihood of a positive result in sputum smear tests but also suggest a high infectivity of pulmonary tuberculosis. Elderly individuals (aged 75 to 89) who are underweight (BMI < 18.5 kg/m2), display symptom of cough, expectoration, hemoptysis and dyspnea-particularly cough and expectoration-and those with extra pulmonary tuberculosis serve as indicators of highly infectious pulmonary tuberculosis patients. These patients may present with more severe condition, carrying a higher bacteria, and being more prone to bacterial elimination. Identification of these patients is crucial, and prompt actions such as timely and rapid isolation measures, cutting off transmission routes, and early empirical treatment of tuberculosis are essential to control the development of the disease.

Asunto(s)

Mycobacterium tuberculosis , Esputo , Tuberculosis Pulmonar , Humanos , Esputo/microbiología , Masculino , Femenino , Mycobacterium tuberculosis/aislamiento & purificación , Anciano , Persona de Mediana Edad , Tuberculosis Pulmonar/microbiología , Tuberculosis Pulmonar/diagnóstico , Adulto , Anciano de 80 o más Años , Adulto Joven , Adolescente