Background Traditional anti-tuberculosis (TB) treatments have limitations. Host-directed therapy (HDT), which boosts the immune response, presents a new treatment approach. This study aimed to identify a new host defense factor against tuberculosis, understand its mechanism, and evaluate its potential as an HDT target. Results Polo-like kinase 2 (PLK2) was discovered as a novel host restriction factor that increases during Mycobacterium tuberculosis infection. It limited bacterial survival by activating the p38 MAPK pathway and enhancing reactive oxygen species (ROS) production. Additionally, the histone deacetylase inhibitor trichostatin A (TSA) served as a PLK2 agonist, boosting PLK2 levels and decreasing bacterial load in vitro and in vivo. Conclusion This study identifies PLK2 as a crucial defense against tuberculosis, working through the p38-ROS axis. Targeting this pathway with TSA shows promise for HDT, offering a new strategy and target for tuberculosis treatment.

Marine biofilms are known as a reservoir of bacterial specialized metabolites, but the majority of these metabolites remain unexplored because most biofilm-associated bacteria have not yet been cultivated or genomically characterized. In a recent study, we isolated and cultivated 713 bacterial strains from marine biofilms and generated their nearly complete genomes. Here, we conduct a systematic analysis of biosynthetic gene clusters (BGCs) contained in these bacterial genomes. A total of 3,146 BGCs are predicted and organized into 2,176 mostly new gene cluster families (GCFs), in comparison with the GCFs in the Minimum Information about a Biosynthetic Gene cluster database, and those from genomes of global seawater bacteria. In particular, certain less-studied microorganisms, such as members of the Roseobacteriaceae family, possess a number of novel BGCs. Moreover, through bacterial antagonistic tests, 50 of the 713 strains inhibit the growth of at least one tested pathogenic bacterial strain. Furthermore, metabolomics followed by molecular networking reveals previously uncharacterized antimicrobial activities associated with known secondary metabolites, represented by the polycyclic tetramate macrolactam alteramide A. IMPORTANCE:Marine microorganisms are important sources of natural products, yet quite a few studies have systematically explored the production of active molecules by marine biofilm-associated bacteria. In the present study, we analyzed nearly complete genomes of 713 strains isolated from marine biofilms to assess their biosynthetic potential. We further conducted experiments to discover compounds with a strong inhibitory effect against pathogenic bacterial strains. This work has laid the groundwork for further prospecting marine biofilm-associated bacterial strains for antibacterial agents.

Autosomal dominant non-syndromic hearing loss (ADNSHL) caused by MYO6 gene variation typically manifests as progressive post-lingual deafness. We identified an 11-member Chinese family across four generations with ADNSHL. We investigated the genetic patterns and mechanisms and employed whole-exome sequencing on genomic DNA derived from peripheral blood to screen and identify pathogenic genes. We verified the potential pathogenicity of the mutation site through minigene assays. Our investigation revealed a novel splice variant, c.554-4A > G (NM_004999.4), located in intron 7 of MYO6, which exhibited clear co-segregation with the hearing impairment phenotype among the family members. Subsequent minigene splicing assays demonstrated that the c.554-4A > G variation resulted in an insertion of three bp in intron 7 of MYO6 (c.554-1_554-3 insTAG, p.184_185insV). The novel splice variant: c.554-4A > G was associated with ADNSHL. Our study expands the spectrum of pathogenic genes and variant sites associated with ADNSHL.

Substantial amounts of phosphorus are discharged into water bodies, leading to an urgent need to develop methods for phosphorus removal. Here, 12 novel polyphosphate-accumulating organisms were identified from marine biofilms through genomic screening and incorporated into a stable community for phosphorus removal from high-salinity water. The synthetic biofilm community achieved an 82% removal efficiency in a marine broth medium. Electron microscopy showed storage of polyphosphate particles in the bacterial cells. Metatranscriptomic analysis indicated expression changes of genes for phosphate transport, as well as relevant metabolic pathways. In particular, pst genes encoding transporters with high phosphate affinity were downregulated at high-phosphorus concentration, whereas pit genes encoding transporters with low phosphate affinity were constitutively expressed. Furthermore, the synthetic biofilm community exhibited remarkable efficiency in removing over 92% of phosphorus from fish farming facility wastewater. Taken together, synthetic community using marine biofilm bacteria is a new strategy of phosphorus removal.

Objectives:This study aimed to investigate the impact of foam macrophages (FMs) on the intracellular survival of Mycobacterium tuberculosis (MTB) and identify the molecular mechanisms influencing MTB survival. Methods:An in vitro FM model was established using oleic acid induction. Transcriptomic and metabolomic analyses were conducted to identify the key molecular pathways involved in FM-mediated MTB survival. Results:Induced FMs effectively restricted MTB survival. Transcriptomic and metabolomic profiling revealed distinct changes in gene and metabolite expression in FMs during MTB infection compared with normal macrophages. Integrated analyses identified significant alterations in the cyclic adenosine monophosphate (cAMP) signaling pathway, indicating that its activation contributes to the FM-mediated restriction of MTB survival. Conclusions:FMs inhibit MTB survival. The cAMP signaling pathway is a key contributor. These findings enhance the understanding of the role of FMs in tuberculosis progression, suggest potential targets for host-directed therapies, and offer new directions for developing diagnostic and therapeutic strategies against tuberculosis.

To investigate the epidemiological profile and cost burden of pediatric inpatients with tuberculous meningitis (TBM) in China. We conducted a descriptive multicenter study involving pediatric TBM inpatients from 9 provincial hospitals and 20 municipal hospitals across 24 provinces in China from January 2016 to December 2021. Sociodemographic and geographic variables, admission and discharge information were extracted from face sheets of discharge medical records to describe the epidemiological characteristics. Length of hospital stay (LOS) and hospitalization expenses were used to assess disease burden. TBM accounted for 0.01

Tuberculosis (TB), the leading cause of death from bacterial infections worldwide, results from infection with Mycobacterium tuberculosis (Mtb). The antitubercular agents delamanid (DLM) and pretomanid (PMD) are nitroimidazole prodrugs that require activation by an enzyme intrinsic to Mtb; however, the mechanism(s) of action and the associated metabolic pathways are largely unclear. Profiling of the chemical-genetic interactions of PMD and DLM in Mtb using combined CRISPR screening reveals that the mutation of rv2073c increases susceptibility of Mtb to these nitroimidazole drugs both in vitro and in infected mice, whereas mutation of rv0078 increases drug resistance. Further assays show that Rv2073c might confer intrinsic resistance to DLM/PMD by interfering with inhibition of the drug target, decaprenylphophoryl-2-keto-b-D-erythro-pentose reductase (DprE2), by active nicotinamide adenine dinucleotide (NAD) adducts. Characterization of the metabolic pathways of DLM/PMD in Mtb using a combination of chemical genetics and comparative liquid chromatography-mass spectrometry (LC-MS) analysis of DLM/PMD metabolites reveals that Rv0077c, which is negatively regulated by Rv0078, mediates drug resistance by metabolizing activated DLM/PMD. These results might guide development of new nitroimidazole prodrugs and new regimens for TB treatment.

Antimicrobial peptides (AMPs) have become a viable source of novel antibiotics that are effective against human pathogenic bacteria. In this study, we construct a bank of culturable marine biofilm bacteria constituting 713 strains and their nearly complete genomes and predict AMPs using ribosome profiling and deep learning. Compared with previous approaches, ribosome profiling has improved the identification and validation of small open reading frames (sORFs) for AMP prediction. Among the 80,430 expressed sORFs, 341 are identified as candidate AMPs with high probability. Most potential AMPs have less than 40% similarity in their amino acid sequence compared to those listed in public databases. Furthermore, these AMPs are associated with bacterial groups that are not previously known to produce AMPs. Therefore, our deep learning model has acquired characteristics of unfamiliar AMPs. Chemical synthesis of 60 potential AMP sequences yields 54 compounds with antimicrobial activity, including potent inhibitory effects on various drug-resistant human pathogens. This study extends the range of AMP compounds by investigating marine biofilm microbiomes using a novel approach, accelerating AMP discovery.

Aortic dissection (AD) is the most catastrophic vascular disease with a high mortality rate. Trimethylamine N-oxide (TMAO), a gut microbial metabolite, has been implicated in the pathogenesis of cardiovascular diseases. However, the role of TMAO in AD and the underlying mechanisms remain unclear. This study aimed to explore the effects of TMAO on AD. Plasma and fecal samples from patients with AD and healthy individuals were collected to analyze TMAO levels and gut microbial species, respectively. The plasma levels of TMAO were significantly higher in 253 AD patients compared with those in 98 healthy subjects (3.47, interquartile range (IQR): 2.33 to 5.18 mu M vs. 1.85, IQR: 1.40 to 3.35 mu M; p < 0.001). High plasma TMAO levels were positively associated with AD severity. An increase in the relative abundance of TMA-producing genera in patients with AD was revealed using 16S rRNA sequencing. In the angiotensin II or beta-aminopropionitrile-induced rodent model of AD, mice fed a TMAO-supplemented diet were more likely to develop AD compared to mice fed a normal diet. Conversely, TMAO depletion mitigated AD formation in the BAPN model. RNA sequencing of aortic endothelial cells isolated from mice administered TMAO revealed significant upregulation of genes involved in inflammatory pathways. The in vitro experiments verified that TMAO promotes endothelial dysfunction and activates nuclear factor (NF)-kappa B signaling. The in vivo BAPN-induced AD model confirmed that TMAO increased aortic inflammation. Our study demonstrates that the gut microbial metabolite TMAO aggravates the development of AD at least in part by inducing endothelial dysfunction and inflammation. This study provides new insights into the etiology of AD and ideas for its management.

SQ109 is a promising candidate drug for the treatment of patients with drug-resistant tuberculosis (DR-TB). The purpose of this study was to investigate the activity of SQ109 against clinical isolates of Mycobacterium tuberculosis (MTB) from patients with multidrug-resistant TB (MDR-TB) and pre-extensively drug-resistant TB (pre-XDR-TB), and to explore new drug-resistant mechanisms of SQ109. We evaluated the in vitro activity of SQ109 against clinical isolates from patients with MDR-TB and pre-XDR-TB using minimal inhibitory concentration (MIC) assay. The drug-resistant gene, mmpL3 of SQ109-resistant strains was sequenced, and a quantitative real-time PCR assay was used to analyze 28 efflux pump genes in SQ109-resistant strains without mmpL3 mutations. The role of candidate efflux pumps mmpL5 and mmpL7 on the MIC of SQ109 was evaluated using recombinantly cloned MmpL5 and MmpL7 expressed in Mycobacterium smegmatis. The MIC90, MIC95 and MIC99 values of SQ109 for 225 clinical isolates of MTB were 0.25 mg/L, 0.5 mg/L and 1.0 mg/L, respectively. Among the pre-XDR strains, six showed resistance to SQ109 despite the absence of gene mutations in mmpL3. In six resistant pre-XDR strains, the MIC of SQ109 decreased with the use of an efflux pump inhibitor, and there was significant upregulation of mmpL5 and mmpL7 in two strains after exposure to SQ109. The presence of MmpL7 in Mycobacterium smegmatis resulted in decreased susceptibility to SQ109, with the MIC increasing from 16 mg/L to 32 mg/L. Our data demonstrated that SQ109 exhibited excellent levels of in vitro activity against MTB. MmpL7 may be a potential gene for MTB resistance to SQ109, providing a useful target for detecting SQ109 resistance in MTB.

Members of the genus Phaeobacter are widely distributed in the marine environment and are known for their ability to produce tropodithietic acid (TDA). Studies investigating the genomic and metabolic features of Phaeobacter strains from marine biofilms are sparse. Here, we analyze the complete genomes of 18 Phaeobacter strains isolated from biofilms on subtidal stones, with the aim of determining their potential to synthesize secondary metabolites. Based on whole-genome comparison and average nucleotide identity calculation, the isolated bacteria are classified as novel strains of Phaeobacter inhibens. Further analysis reveals a total of 153 biosynthetic gene clusters, which are assigned to 32 gene cluster families with low similarity to previously published ones. Complete TDA clusters are identified in 14 of the 18 strains, while in the other 4 strains the TDA clusters are rather incomplete and scattered across different chromosome and plasmid locations. Phylogenetic analysis suggests that their presence or absence may be potentially attributed to horizontal gene transfer. High-performance liquid chromatography–mass spectrometry analysis demonstrates the production of TDA in all the examined strains. Furthermore, the Phaeobacter strains have strong antibacterial activity against the pathogenic strain Vibrio owensii ems001, which is associated with acute hepatopancreatic necrosis in South American white shrimp. Altogether, this study ameliorates our knowledge of marine biofilm-associated Phaeobacter and offers new avenues for exploiting marine antimicrobial agents.

The 2022 World Health Organization guidelines recommend use of two core anti-tuberculosis (TB) drugs, bedaquiline (BDQ) and clofazimine (CFZ), for treatment of drug-resistant (DR)-TB. However, several mutated Mycobacterium tuberculosis (MTB) genes, conferring BDQ and CFZ resistance, have been reported that predominantly arose from sporadic mutations that have not been comprehensively characterized. Herein, MTB clinical isolates collected from drug-susceptible (DS)-, multidrug-resistant (MDR)-, and extensively drug-resistant (XDR)-TB patients were cultured in vitro with BDQ or CFZ to generate progeny strains with resistance to these drugs. Progeny strains exposed to CFZ exhibited increased CFZ minimum inhibitory concentrations (MICs) that exceeded MIC increases of BDQ-exposed progeny strains. Notably, mmpR and pepQ mutations accounted for 83% and 17% of BDQ-induced spontaneous gene mutations, respectively, and 86% and 14% of CFZ-induced spontaneous gene mutations, respectively. Analyses of predicted mutation-induced changes in amino acid sequences and structures of MmpR and PepQ mutants revealed several point mutations affected sequence conversation and functionality as an underlying mechanism for observed acquired BDQ/CFZ resistance. Moreover, our results revealed differences in patterns of BDQ- and CFZ-induced acquired spontaneous mutations that may enhance our understanding of MTB BDQ/CFZ-resistance mechanisms.IMPORTANCE This study of MTB drug resistance mechanisms revealed patterns of spontaneous MTB mutations associated with acquired BDQ and CFZ resistance that arose after clinical MTB isolates were cultured in vitro with BDQ or CFZ. Results of protein sequence and structural analyses provided insights into potential mechanisms underlying associations between MTB gene mutations and DR phenotypes. Taken together, these results revealed differences in acquired BDQ and CFZ resistance mechanisms as a new perspective that may enhance our understanding of BDQ/CFZ resistance mechanisms and facilitate the development of new methods for detecting MTB drug resistance genes.

High-risk neuroblastoma (HR-NB) is an aggressive childhood cancer that responds poorly to currently available therapies and is associated with only about a 50% 5-year survival rate. MYCN amplification is a critical driver of these aggressive tumors, but so far there have not been any approved treatments to effectively treat HR-NB by targeting MYCN or its downstream effectors. Thus, the identification of novel molecular targets and therapeutic strategies to treat children diagnosed with HR-NB represents an urgent unmet medical need. Here, we conducted a targeted siRNA screening and identified TATA box-binding protein-associated factor RNA polymerase I subunit D, TAF1D, as a critical regulator of the cell cycle and proliferation in HR-NB cells. Analysis of three independent primary NB cohorts determined that high TAF1D expression correlated with MYCN-amplified, high-risk disease and poor clinical outcomes. TAF1D knockdown more robustly inhibited cell proliferation in MYCN-amplified NB cells compared with MYCN-non-amplified NB cells, as well as suppressed colony formation and inhibited tumor growth in a xenograft mouse model of MYCN-amplified NB. RNA-seq analysis revealed that TAF1D knockdown downregulates the expression of genes associated with the G2/M transition, including the master cell-cycle regulator, cell-cycle-dependent kinase 1 (CDK1), resulting in cell-cycle arrest at G2/M. Our findings demonstrate that TAF1D is a key oncogenic regulator of MYCN-amplified HR-NB and suggest that therapeutic targeting of TAF1D may be a viable strategy to treat HR-NB patients by blocking cell-cycle progression and the proliferation of tumor cells.

Objective: To investigate the molecular regulatory mechanism of Mycobacterium tuberculosis (MTB) protein Rv0309 to promote the survival of Mycobacterium smegmatis (Ms) in macrophages. Methods: Using Ms as a model to study Mycobacterium tuberculosis, recombinant Ms transfected with pMV261 and PMV261-RV0309 in the control group and RAW264.7 cells were constructed. The effect of Rv0309 protein on intracellular survival of Ms was investigated by counting colony forming units (CFUs). Mass spectrometry was used to screen proteins interacting with host protein Rv0309, and immunocoprecipitate (Co-IP) was used to verify that host protein STUB1 could interact with host protein Rv0309. STUB1 gene knock-out RAW264.7 cells were infected with Ms, and CFUs were counted to explore the effect of protein Rv0309 on intracellular survival of Ms after STUB1 gene knock-out. STUB1 gene knock-out RAW264.7 cells were infected with Ms, and after obtaining samples, Western blotting assay was performed to explore the effect of protein Rv0309 on autophagy function of macrophages after STUB1 gene knock-out. Statistical analysis was performed using GraphPad Prism 8 software. T-test was selected for analysis in this experiment, with P<0.05 was considered statistically significant. Results: Western blotting showed that Rv0309 was expressed in M. smegmatis and secreted extracellularly. The CFUs of the Ms-Rv0309 group was higher than that of Ms-pMV261 group at 24 h after THP-1 macrophage infection, and the difference was statistically significant (P<0.05). The trend of infected RAW264.7 macrophages was the same as that of infected THP-1 macrophages. The Co-IP results showed that the corresponding Flag and HA bands appeared in the results of immunoprecipitation (IP):Flag and IP: HA. The level of CFUs in the experimental group with STUB1 deletion was significantly higher than that in the control group without STUB1 deletion. Compared with Ms-pMV261, the CFUs in the Ms-Rv0309 group was significantly higher than that in the Ms-pMV261 group. The gray scale of LC3Ⅱ bands of Ms-Rv0309 in experimental group was lighter than that of Ms-pMV261 in the control group at the corresponding time point, and the result was most significant at 8 h (LC3Ⅱ/β-actin: 0.76±0.05 vs 0.47±0.07), the difference being statistically significant (P<0.05). After STUB1 genome knock-out, the gray level of LC3Ⅱ bands at the corresponding time was lighter than that without STUB1 genome knock-out. Comparison of the results of Ms-pMV261 and Ms-Rv0309 strains revealed that LC3Ⅱ band gray Rv0309 group was lighter at the corresponding time compared with pMV261 group. Conclusions: MTB protein Rv0309 can be successfully expressed in M. smegmatis and secreted extracellularly, which can inhibit the autophagy process of macrophages. Protein Rv0309 interacts with host protein STUB1 to inhibit macrophage autophagy and promote intracellular survival of Ms.

目的 分析溶质载体家族7成员11(SLC7A11)在有无MYCN基因扩增的神经母细胞瘤(NB)细胞系和临床样本中的表达及其与患儿预后相关性,研究SLC7A11对MYCN扩增高危NB增殖的影响.方法 利用GEO数据库GSE49710数据集、TARGET数据库和R2数据库GSE45547数据集分析NB临床样本中SLC7A11 mRNA水平与MYCN基因扩增状态和NB患儿预后相关性.应用实时荧光定量PCR(RT-qPCR)检测MYCN扩增NB细胞系SK-N-BE(2)和IMR32细胞以及MYCN非扩增NB细胞系CHLA-255和SH-SY5Y细胞中SLC7A11 mRNA水平.在MYCN扩增NB细胞系SK-N-BE(2)细胞中,利用2条不同序列小干扰RNA瞬时敲低SLC7A11 mRNA,应用RT-qPCR和Western印迹法检测SLC7A11 mRNA和SLC7A11表达及MYCN mRNA和N-MYC表达,采用结晶紫染色和实时无标记细胞分析(RTCA)技术观察NB细胞增殖情况.免疫荧光法检测增殖标记物Ki-67表达情况.利用短发夹RNA慢病毒感染方法构建稳定敲低SLC7A11的SK-N-BE(2)细胞,RT-qPCR和Western印迹法检测SLC7A11的稳定敲低效果和MYCN水平,采用克隆形成实验观察NB细胞克隆形成能力.结果 分析NB临床样本GSE49710和GSE45547数据集发现,在MYCN扩增NB中,SLC7A11 mRNA水平显著高于非MYCN扩增NB(P<0.05,P<0.01),且TARGET数据库和R2数据库GSE45547数据集分析表明SLC7A11 mRNA水平与NB患儿生存率呈负相关(P<0.05,P<0.01).SLC7A11在MYCN扩增NB细胞系SK-N-BE(2)和IMR32中的表达均显著高于非扩增细胞系CHLA-255和SH-SY5Y(P<0.01).与对照敲低组相比,瞬时敲低SLC7A11导致MYCN扩增NB细胞增殖显著减慢(P<0.01),Ki-67阳性细胞比例明显减少(P<0.05);稳定敲低SLC7A11显著减少了NB细胞克隆形成数(P<0.01).瞬时和稳定敲低SLC7A11对MYCN mRNA和N-MYC蛋白水平均未见明显影响.结论 SLC7A11在MYCN扩增NB细胞系和临床样本中高表达,且其表达水平与患儿预后呈负相关,敲低SLC7A11显著抑制SK-N-BE(2)细胞的增殖和克隆形成能力.

Delamanid (DLM) and pretomanid (PTM) are recent additions to the anti-tuberculosis (TB) drug armamentarium, and they offer more effective options for drug-resistant TB treatment. In particular, DLM is included in Group C, which is recommended for use in longer multidrug-resistant (MDR)-TB regimens.

由结核分枝杆菌引起的结核病自2007年以来一直位居单一传染性疾病死因之首.结核病流行的主要原因是由于结核分枝杆菌能在宿主细胞内长期休眠,对宿主防御和药物治疗具有很强的抵抗力.结核分枝杆菌的哺乳动物细胞入侵(mammalian cell entry,Mce)蛋白家族在其侵袭和细胞内存活中起着重要作用,Mce蛋白家族有4个mce操纵子(mnce1-4)编码.其中,mce4操纵子及其编码的Mce4蛋白家族在诱导病原菌入侵、调控宿主免疫、摄取利用胆固醇的过程中至关重要.笔者综述了 mce4操纵子及Mce4蛋白家族的研究进展,以便对Mce4蛋白在结核分枝杆菌发病机制中的作用有更深入的认识.同时,也能为结核病的治疗提供潜在的新靶点.

Background Apart from bactericidal effects, anti-tuberculosis drugs can interfere with the host’s immune system. In this study, we analyzed the role of delamanid (DLM), an inhibitor of mycolic acid synthesis of mycobacterial cell wall, on human macrophages. Methods Based on a cohort of multidrug-resistant tuberculosis (MDR-TB) patients treated with DLM, the levels of C-reaction protein (CRP) and cytokines in the plasma were monitored using immunoturbidimetric assay and flow cytometry, respectively. We investigated the role of DLM on CXCL10 expression in U937 cell model using the following methods: cell viability assay, reverse transcription-quantitative polymerase chain reaction, enzyme linked immunosorbent assay, immunoblot, and transwell co-culture assay. Results A total of 23 MDR-TB patients were included, comprising of 13 patients treated with optimized background therapeutic regimen (OBR) plus DLM regimen (OBR+DLM) and 10 patients treated with OBR plus placebo. DLM administration was associated with a significant reduce in circulating CRP level. Correspondingly, after treatment, the level of CXCL10 in patients treated with OBR+DLM was significantly lower than that with control. Using cell model, DLM dramatically suppressed CXCL10 expression, which majorly depended on inhibiting the JAK/STAT pathway, and impaired the migration of PBMCs. Conclusion Our data firstly demonstrate that DLM suppresses CXCL10 expression via regulation of JAK2/STAT1 signaling and correlates with reduced inflammation in MDR-TB patients. DLM could be used as a potential drug for immunotherapy of patients with overactive immune response due to CXCL10.

Tuberculous meningitis (TBM), the most lethal and disabling form of tuberculosis (TB), may be related to gut microbiota composition, warranting further study. Here we systematically compared gut microbiota compositions and blood cytokine profiles of TBM patients, pulmonary TB patients, and healthy controls. Notably, the significant gut microbiota dysbiosis observed in TBM patients was associated with markedly high proportions of Escherichia-Shigella species as well as increased blood levels of tumor necrosis factor alpha (TNF-α) and interleukin 6 (IL-6). Next, we obtained a fecal bacterial isolate from a TBM patient and administered it via oral gavage to mice in order to develop a murine gut microbiota dysbiosis model for use in exploring mechanisms underlying the observed relationship between gut microbial dysbiosis and TBM. Thereafter, cells of commensal Escherichia coli (E. coli) were isolated and administered to model mice by gavage and then mice were inoculated with Mycobacterium tuberculosis (M. tuberculosis). Subsequently, these mice exhibited increased blood TNF-α levels accompanied by downregulated expression of tight junction protein claudin-5, increased brain tissue bacterial burden, and elevated central nervous system inflammation relative to corresponding indicators in controls administered PBS by gavage. Thus, our results demonstrated that a signature dysbiotic gut microbiome profile containing a high proportion of E. coli was potentially associated with an increased circulating TNF-α level in TBM patients. Collectively, these results suggest that modulation of dysbiotic gut microbiota holds promise as a new strategy for preventing or alleviating TBM. IMPORTANCE As the most severe form of tuberculosis, the pathogenesis of tuberculous meningitis (TBM) is still unclear. Gut microbiota dysbiosis plays an important role in a variety of central nervous system diseases. However, the relationship between gut microbiota and TBM has not been identified. In our study, significant dysbiosis in gut microbiota composition with a high proportion of E. coli and increased levels of TNF-α in plasma was noted in TBM patients. A commensal E. coli was isolated and shown to increase the plasma level of TNF-α and downregulate brain tight junction protein claudin-5 in the murine model. Gavage administration of E. coli aggravated the bacterial burden and increased the inflammatory responses in the central nervous system after M. tuberculosis infection. Dysbiosis of gut microbiota may be a promising therapeutic target and biomarker for TBM prevention or treatment.

Objective: To compare the diagnostic performance of next-generation sequencing (NGS) detection methods in sputum samples and Mycobacterium tuberculosis strains, in order to explore the feasibility of the NGS method to detect drug resistance in sputum specimens. Methods: In this retrospective study, the sputum specimens and corresponding clinical isolates of 50 pulmonary tuberculosis patients admitted to Beijing Chest Hospital from January 2017 to December 2017 were collected. The gene mutations of katG, inhA, rpoB, embA, embB, rpsL, rrs, gyrA, gyrB and tlyA in sputum specimens and corresponding clinical isolates were detected by NGS method. The phenotypic drug susceptibility test (DST) of the strains was carried out by the proportion method. Using DST results as a reference, the sensitivity, specificity, positive predictive value and negative predictive value of the NGS method for clinical strains and sputum specimens, as well as the consistency statistic (Kappa) with phenotype DST were calculated respectively. The Chi-square test was used to compare the accuracy of the NGS testing in sputum samples and strain samples. Results: The results showed that rpoB(63.83%, 30/47) and rrs(57.45%, 27/47) were the most common mutated genes, followed by katG(46.81%, 22/47), rpsL(29.79%, 14/47), gyrA(27.66%, 13/47), embB(21.28%, 10/47), tlyA(12.77%, 6/47), gyrB(8.51%, 4/47), and inhA promoter(19.15%, 9/47), embA promoter region (12.77%, 6/47) mutation. when the NGS method was compared with the resistance phenotype of isoniazid, rifampicin, ethambutol, second-line injectable drugs (streptomycin, capreomycin, kanamycin, amikacin), levofloxacin, the sensitivity were 85.71%, 91.67%, 77.78%, 81.82%, 100.00%, 87.50%, 100.00%, 69.23%, and the specificity were 100.00%, 94.12, 87.50%, 89.47%, 97.06%, 96.97%, 94.29%, 89.29% in sputum samples, while in strain samples, the sensitivity were 92.86%, 100.00%, 81.82%, 86.96%, 88.89%, 80.00%, 100.00%, 85.71%. The specificity were 100.00%, 92.86%, 87.10%, 94.74%, 100.00%, 100.00%, 97.14%, 92.86%. Compared with the phenotypic drug susceptibility results, the NGS method has better detection performance for isoniazid, rifampicin, capreomycin, kanamycin, and amikacin in sputum specimens (Kappa≥0.75); while among the strains, the NGS method had a good detection performance for isoniazid, rifampicin, streptomycin, capreomycin, kanamycin, amikacin and levofloxacin (Kappa≥0.75). With the accuracy of the NGS method for detecting strains as a reference, there was no statistically significant difference in the accuracy of all drug resistance detected between strains and sputum specimens. Conclusions: This study showed that the NGS technology was effective in predicting the resistance of isoniazid, rifampicin, and second-line injectable drugs (capreomycin, kanamycin and amikacin) by detecting sputum samples and strain genotypes, suggesting the feasibility and potential of direct detection of sputum samples by the NGS method as an early detection method for drug resistance.