Epithelial TIPE1 Protein Guards against Colitis by Inhibiting TNF-α-Mediated Inflammation.

Intestinal epithelial cells (IECs) at the internal/external interface orchestrate the mucosal immune response, and IEC dysfunction has been linked to multiple inflammatory diseases, including inflammatory bowel disease. In this study, we found that a member of the TNF-α-induced protein 8 (TNFAIP8 or TIPE) family called TIPE1 is indispensable for maintaining epithelial cell barrier integrity and homeostasis under inflammatory conditions. TIPE1-deficient mice, or chimeric mice that were deficient in TIPE1 in their nonhematopoietic cells, were more sensitive to dextran sulfate sodium-induced experimental colitis; however, TIPE1 deficiency had no impact on the development of inflammation-associated and sporadic colorectal cancers. Mechanistically, TIPE1 prevented experimental colitis through modulation of TNF-α-dependent inflammatory response in IECs. Importantly, genetic deletion of both TIPE1 and its related protein TNFAIP8 in mice led to the development of spontaneous chronic colitis, indicating that both of these two TIPE family members play crucial roles in maintaining intestinal homeostasis. Collectively, our findings highlight an important mechanism by which TIPE family proteins maintain intestinal homeostasis and prevent inflammatory disorders in the gut.

Polarized Th2 cells attenuate high-fat-diet induced obesity through the suppression of lipogenesis.

Immune cells, such as macrophages, B cells, neutrophils and T cell subsets, have been implicated in the context of obesity. However, the specific role of Th2 cells in adipose tissue function has remained elusive. Eight-week-old male CD3ε─/─ mice were randomly divided into two groups (≥ 5 mice per group): one received intravenous injection of Th2 cells isolated from LATY136F mice, while the other receiving PBS as a control. Both of groups were subjected to a high-fat diet (HFD). The adoptive transfer of polarized Th2 cells led to a significant reduction in obesity following a HFD. This reduction was accompanied by improvements in hepatic steatosis, glucose intolerance, and insulin resistance. Mechanistically, Th2 cell treatment promoted oxidative phosphorylation of adipocytes, thereby contributing to a reduction of lipid droplet accumulation. These findings suggest that Th2 cell therapy represents a novel approach for treating diet-induced obesity and other diseases involving lipid droplet accumulation disorders.

Loss of Bcl-3 regulates macrophage polarization by promoting macrophage glycolysis.

M1/M2 macrophage polarization plays an important role in regulating the balance of the microenvironment within tissues. Moreover, macrophage polarization involves the reprogramming of metabolism, such as glucose and lipid metabolism. Transcriptional coactivator B-cell lymphoma-3 (Bcl-3) is an atypical member of the IκB family that controls inflammatory factor levels in macrophages by regulating nuclear factor kappa B pathway activation. However, the relationship between Bcl-3 and macrophage polarization and metabolism remains unclear. In this study, we show that the knockdown of Bcl-3 in macrophages can regulate glycolysis-related gene expression by promoting the activation of the nuclear factor kappa B pathway. Furthermore, the loss of Bcl-3 was able to promote the interferon gamma/lipopolysaccharide-induced M1 macrophage polarization by accelerating glycolysis. Taken together, these results suggest that Bcl-3 may be a candidate gene for regulating M1 polarization in macrophages.

Treatment outcomes of retreated patients with isoniazid/rifampicin resistant pulmonary tuberculosis.

BACKGROUND: About 8% of TB cases worldwide are estimated to have rifampicin-susceptible, isoniazid-resistant tuberculosis (Hr-TB), ranging from 5 to 11% regions. However, Hr-TB has not received much attention while comparing to be given high priority to the management of rifampicin-resistant tuberculosis (RR-TB). This study aimed to compare the differences of treatment effects for Hr-TB and RR-TB, so as to intensify the treatment and management of Hr-TB. METHODS: A retrospective study was used to collect bacteriologically positive retreated patients with isoniazid/rifampicin resistant pulmonary tuberculosis, who were conducted at 29 tuberculosis control institutions in China from July 2009 to June 2021. We assessed effectiveness and safety of retreated patients with isoniazid/ rifampicin resistant pulmonary tuberculosis. RESULTS: A total of 147 with either positive smear or cultures were enrolled, and 80 cases were in Hr-TB group and 67 cases were in RR-TB group. There was no significant difference in terms of age, sex, body mass, type of retreatment and comorbid diabetes between the two groups (P > 0.05). The rate of number of lesions involving lung fields ≥ 3 in Hr-TB group 75.9% (60/79) was significantly higher than RR-TB group 56.7% (38/67) (χ2 = 6.077, P = 0.014). There was no statistically significant difference (P = 0.166) with regard to the treatment outcomes of the two groups, the cure rates were 54.7% (41/75) and 53.6% (30/56), respectively, and the failure rate in Hr-TB group 22.7% (17/75) was 10% higher than RR-TB group 10.7% (6/56). The rate of negative sputum smear at the end of the second month (65.7%) in the Hr-TB group was significantly lower than that in the RR-TB group (85.7%) (P = 0.025). There were no significant differences in the incidences of serious adverse reactions and chest X-ray changes between the two groups (P > 0.05). During the 5-year follow-up, recurrence in the Hr-TB group (7 cases, 14.9%) was no significantly lower than that in the RR-TB group (4 cases, 11.8%) (P = 0.754). CONCLUSION: The treatment of retreated Hr-TB patients was difficult and could be statistically similar or considerably worse than RR-TB. It's urgent to conduct further evaluation of the treatment status quo to guide the guideline development and clinical practice of Hr-TB patients.

Development and Validation of a Nomogram for Prediction of QT Interval Prolongation in Patients Administered Bedaquiline-Containing Regimens in China: a Modeling Study.

Corrected QT duration (QTc) interval prolongation is the most frequent adverse event associated with bedaquiline (BDQ) use. It may affect the safety of antituberculosis therapy, which leads to the consequent demands of needing to monitor during therapy. Our objective was to establish and validate a prediction model for estimating the risk of QTc prolongation after initiation of BDQ-containing regimens to multidrug-resistant tuberculosis (MDR-TB) patients. We constructed an individualized nomogram model based on baseline demographic and clinical characteristics of each patient within a Chinese cohort during BDQ treatment. The generalizability of this model was further validated through use of externally acquired data obtained from Beijing Chest Hospital from 2019 to 2020. Overall, 1,215 and 165 patients were included in training and external validation cohorts, respectively, whereby during anti-TB drug treatment, QTc prolongation was observed in 273 (22.5%) and 29 (17.6%) patients within these respective cohorts, for whom QTc values were >500 ms in 86 (31.5%) and 10 (34.7%) patients, respectively. Next, a total of four Cox proportional hazards models were created and assessed; then, nomograms derived from the models were plotted based on independent predictors of clofazimine, baseline QTc interval, creatinine, extensive drug-resistance (XDR), moxifloxacin, levofloxacin, and sex. Nomogram analysis revealed concordance index values of 0.723 (95% confidence interval [CI], 0.695 to 0.750) for the training cohort and 0.710 (95% CI, 0.627 to 0.821) for the external validation cohort, thus indicating relatively fair agreement between predicted and observed probabilities of QTc prolongation occurrence based on data obtained during 8-week, 16-week, and 24-week anti-TB treatment of both cohorts. Taken together, results obtained using these models demonstrated that coadministration of clofazimine and abnormal baseline QTc interval significantly contributed to QTc prolongation development during MDR-TB patient treatment with a BDQ-containing anti-TB treatment regimen.

Effects of Bedaquiline on Antimicrobial Activity and Cytokine Secretion of Macrophages Infected with Multidrug-Resistant Mycobacterium tuberculosis Strains.

Background: Bedaquiline (Bdq) exerts bactericidal effects against drug-susceptible and drug-resistant Mycobacterium tuberculosis strains, including multidrug-resistant M. tuberculosis strains (MDR-MTBs). However, few reported investigations exist regarding Bdq effects on MDR-MTBs-infected macrophages activities and cytokine secretion. Here, Bdq bactericidal activities against MDR-MTBs and related cellular immune mechanisms were explored. Methods: Macrophages infected with MDR-MTBs or H37Rv received Bdq treatments (4 h/8 h/24 h/48 h) at 1 × the minimum inhibitory concentration (1 × MIC), 10 × MIC and 20 × MIC. Intracellular colony-forming units (CFUs) and culture supernatant IL-12/23 p40, TNF-α, IL-6, and IL-10 were determined using the Luminex® 200TM system. Normally distributed continuous data (mean ± standard deviation) were analyzed using t-test or F-test (SPSS 25.0, P < 0.05 deemed statistically significant). Results: (1) 100% of Bdq-treated macrophages (all doses applied over 4-48 h) survived with 0% inhibition of proliferation observed. (2) Intracellular CFUs of Bdq-treated MDR-MTBs-infected macrophages decreased over 4-48 h of treatment, were lower than preadministration and control CFUs, decreased with increasing Bdq dose, and resembled H37Rv-infected group CFUs (48 h). (3) For MDR-MTBs-infected macrophages (various Bdq doses), IL-12/23 p40 levels resembled preadministration group levels and exceeded controls (4 h); TNF-α levels exceeded preadministration group levels (24 h/48 h) and controls (24 h); IL-12/23 p40 and TNF-α levels resembled H37Rv-infected group levels (4 h/8 h/24 h/48 h); IL-6 levels exceeded preadministration and H37Rv-infected group levels (24 h/48 h) and controls (24 h); IL-10 levels resembled preadministration and H37Rv-infected group levels (4 h/8 h/24 h/48 h) and were lower than controls (24 h/48 h); IL-12/23 p40 and IL-10 levels remained unchanged as intracellular CFUs changed, with IL-12/23 p40 levels exceeding controls (4 h) and IL-10 levels remaining lower than controls (24 h/48 h); TNF-α and IL-6 levels increased as intracellular CFUs decreased (24 h/48 h) and exceed controls (24 h). Conclusion: Bdq was strongly bactericidal against intracellular MDR-MTBs and H37Rv in a time-dependent, concentration-dependent manner. Bdq potentially exerted immunomodulatory effects by inducing high-level Th1 cytokine expression (IL-12/23 p40, TNF-α) and low-level Th2 cytokine expression (IL-10).

Wdpcp regulates cellular proliferation and differentiation in the developing limb via hedgehog signaling.

BACKGROUND: Mice with a loss of function mutation in Wdpcp were described previously to display severe birth defects in the developing heart, neural tube, and limb buds. Further characterization of the skeletal phenotype of Wdpcp null mice was limited by perinatal lethality. RESULTS: We utilized Prx1-Cre mice to generate limb bud mesenchyme specific deletion of Wdpcp. These mice recapitulated the appendicular skeletal phenotype of the Wdpcp null mice including polydactyl and limb bud signaling defects. Examination of late stages of limb development demonstrated decreased size of cartilage anlagen, delayed calcification, and abnormal growth plates. Utilizing in vitro assays, we demonstrated that loss of Wdpcp in skeletal progenitors lead to loss of hedgehog signaling responsiveness and associated proliferative response. In vitro chondrogenesis assays showed this loss of hedgehog and proliferative response was associated with decreased expression of early chondrogenic marker N-Cadherin. E14.5 forelimbs demonstrated delayed ossification and expression of osteoblast markers Runx2 and Sp7. P0 growth plates demonstrated loss of hedgehog signaling markers and expansion of the hypertrophic zones of the growth plate. In vitro osteogenesis assays demonstrated decreased osteogenic differentiation of Wdpcp null mesenchymal progenitors in response to hedgehog stimulation. CONCLUSIONS: These findings demonstrate how Wdpcp and associated regulation of the hedgehog signaling pathway plays an important role at multiple stages of skeletal development. Wdpcp is necessary for positive regulation of hedgehog signaling and associated proliferation is key to the initiation of chondrogenesis. At later stages, Wdpcp facilitates the robust hedgehog response necessary for chondrocyte hypertrophy and osteogenic differentiation.

Reduced Susceptibility of Mycobacterium tuberculosis to Bedaquiline During Antituberculosis Treatment and Its Correlation With Clinical Outcomes in China.

BACKGROUND: We aimed to assess the proportion of multidrug-resistant tuberculosis (MDR-TB) cases with initial bedaquiline (BDQ) resistance, monitor the dynamics of BDQ susceptibility of Mycobacterium tuberculosis isolates during therapy, and correlate susceptibility with MDR-TB patient clinical outcomes in China. METHODS: A retrospective, cohort study of MDR-TB patients was conducted, with positive cultures collected from cases at 13 sites. Patients with nontuberculous mycobacterial infection during anti-TB therapy were excluded. BDQ minimal inhibitory concentrations (MICs) were determined using a 7H9 Middlebrook broth-based microdilution method. Mutations that conferred BDQ resistance were detected via Sanger sequencing. RESULTS: A total of 277 patients receiving BDQ treatment were studied, with BDQ resistance noted in isolates from 2.2% (6/277) of MDR-TB cases, sputum conversion observed in 5 cases, and culture conversion observed in 138 cases within 2 weeks. Another 15 and 30 isolates were excluded from final analysis due to failures in obtaining subcultures and serial isolates, respectively. Of 94 cases that yielded serial isolates, 11 exhibited reduced BDQ susceptibility, while 3 of 5 cases with acquired resistance failed to culture-convert. Sequence analysis revealed that 6 of 11 BDQ-resistant isolates harbored Rv0678 mutations; no mutations were detected in 3 other BDQ resistance-associated genes. No significant intergroup difference in culture conversion time was observed. CONCLUSIONS: MDR-TB patients in China exhibited a low initial BDQ resistance rate. MDR-TB cases with acquired BDQ resistance were at greater risk of treatment failure relative to initially BDQ-resistant cases. Rv0678 mutations accounted for BDQ resistance in this cohort.

Stepwise selection of mutation conferring fluroquinolone resistance: multisite MDR-TB cohort study.

In this study, we demonstrate that fluroquinolone (FQ) is at risk of acquired drug resistance after continuous exposure. The reduced susceptibility is observed in subsequent Mycobacterium tuberculosis isolates from patients without FQ exposure. The stepwise selection of mutation of increasing FQ resistance highlights the urgent need for monitoring FQ resistance in multidrug-resistant tuberculosis patients throughout the entire treatment course.

Multicenter feasibility study to assess external quality panels for molecular diagnostics for tuberculosis in China.

The roll-out of molecular diagnostic tools continues to be the most important shift in the tuberculosis diagnostic landscape. The aim of this study was to develop a novel external quality assessment (EQA) panels for molecular TB diagnostics. In addition, we also assessed the performance of the laboratories with the EQA panels in China. Dried Mycobacterium tuberculosis (MTB) DNA in the chelex resin was designed as part of an EQA program. The storage of genomic DNA in the chelex resin layer had no effect on the stability of genomic DNA, even after 12 weeks of storage. Seventy-one laboratories have participated in EQA of molecular diagnostics for TB diagnosis in 2018. GeneXpert (74.6%, 53/71) was the most predominant molecular method, followed by GeneChip (32.3%, 23/71), MeltPro (22.5%, 16/71), and TB-LAMP (7.0%, 5/71). Out of 105 EQA panels, 103 EQA results (98.1%) achieved perfect scores, whereas the other two (1.9%) had satisfactory scores. There were a total of two false-negative results reported from two laboratories with local LAMP, respectively. In conclusion, we firstly develop feasible EQA panels for molecular diagnostics for tuberculosis in China. Our data demonstrate that a majority of participating laboratories are able to produce perfect results with molecular diagnostics in China, giving us important hints for the implementation of molecular diagnostics.

Effect of FGF/FGFR pathway blocking on lung adenocarcinoma and its cancer-associated fibroblasts.

Cancer-associated fibroblasts (CAFs) are known to promote tumourigenesis through various mechanisms. Fibroblast growth factor (FGF)/FGF receptor (FGFR)-dependent lung cancers have been described. We have developed a mouse model of lung adenocarcinoma that was constructed through the induction of Fgf9 overexpression in type 2 alveolar cells. The expression of Fgf9 in adult lungs resulted in the rapid development of multiple adenocarcinoma-like tumour nodules. Here, we have characterised the contribution of CAFs and the Fgf/Fgfr signalling pathway in maintaining the lung tumours initiated by Fgf9 overexpression. We found that CAF-secreted Fgf2 contributes to tumour cell growth. CAFs overexpressed Tgfb, Mmp7, Fgf9, and Fgf2; synthesised more collagen, and secreted inflammatory cell-recruiting cytokines. CAFs also enhanced the conversion of tumour-associated macrophages (TAMs) to the tumour-supportive M2 phenotype but did not influence angiogenesis. In vivo inhibition of Fgfrs during early lung tumour development resulted in significantly smaller and fewer tumour nodules, whereas inhibition in established lung tumours caused a significant reduction in tumour size and number. Fgfr inhibition also influenced tumour stromal cells, as it significantly abolished TAM recruitment and reduced tumour vascularity. However, the withdrawal of the inhibitor caused a significant recurrence/regrowth of Fgf/Fgfr-independent lung tumours. These recurrent tumours did not possess a higher proliferative or propagative potential. Our results provide evidence that fibroblasts associated with the Fgf9-induced lung adenocarcinoma provide multiple means of support to the tumour. Although the Fgfr blocker significantly suppressed the tumour and its stromal cells, it was not sufficient to completely eliminate the tumour, probably due to the emergence of alternative (resistance/maintenance) mechanism(s). This model represents an excellent tool to further study the complex interactions between CAFs, their related chemokines, and the progression of lung adenocarcinoma; it also provides further evidence to support the need for a combinatorial strategy to treat lung cancer. © 2019 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Development and validation of external quality assessment panels for mycobacterial culture testing to diagnose tuberculosis in China.

Mycobacterial culture remains the gold standard for detection of Mycobacterium tuberculosis (MTB) in clinical samples. However, no external quality assessment (EQA) tools exist to validate results obtained using this sophisticated method. Therefore, we developed EQA panels to assess the quality of mycobacterial culture results produced by designated TB hospitals in China. Artificial sputum containing methylcellulose was used to supplement quantified mycobacterial solutions to simulate culture-negative and culture-positive clinical sputum samples of low or high mycobacterial concentration, respectively. After storage of the quantified simulated EQA panels for 4 weeks at 4 °C, experimental bacterial quantification of the panels was again conducted, with no impact of artificial sputum on mycobacterial culture results observed. Next, 47 tuberculosis (TB) hospitals were recruited for evaluation of the EQA panels. Overall, 29 hospitals (61.7%) produced mycobacterial culture test results matching expected results for the EQA panels, while the remaining 18 (38.3%) hospitals did not. False-negative results for the low mycobacterial concentration panel sample accounted for 33 (73.3%) diagnostic errors. Compared with hospitals using solid culture methods as a control group, hospitals using the liquid culture method were less likely to produce uncertified results (aOR 0.064, 95% CI 0.005-0.770). In conclusion, we first developed then evaluated EQA panels for validation of mycobacterial culture testing in China. Our data demonstrate that approximately one-third of TB hospitals failed to produce results that met criteria for classification as certified mycobacterial culture testing providers, emphasizing the importance of quality control and quality assurance in TB diagnostics.

Efficacy of ultra-short course chemotherapy for new smear positive drug susceptible pulmonary tuberculosis: study protocol of a multicenter randomized controlled clinical trial.

BACKGROUND: Shortening the standard 6-month treatment for drug-susceptible pulmonary tuberculosis (DS-PTB) would be a major improvement for TB case management and disease control. METHODS: We are conducting a randomized, open-label, controlled, non-inferiority trial involving patients with smear-positive, newly diagnosed DS-PTB cases nationwide to assess the efficacy and safety of two 4.5- month regimens in comparison to the standard 6-month WHO recommended regimen. The regimen used in one experiment group is a 4.5-month fluoroquinolone-containing regimen, which consists of full course of levofloxacin, isoniazid (H), rifampin (R), parazinamid (Z) and ethambutol (E). Regimen used in the second experiment group includes 4.5-month full course of H, R, Z, E with levofloxacin removed. Patients in the control group, receive H, R, Z and E for 2 months, followed by 4 months of H and R. The primary endpoint is treatment failure or relapse within 24 month after treatment completion. DISCUSSION: Results from this trial along with other studies will contribute to the science of constructing a shorter, effective and safe regiment for TB patients. TRIAL REGISTRATION: The protocol has been registered on ClinicalTrials.gov on 2 September,2016 with identifier NCT02901288 .

Later emergence of acquired drug resistance and its effect on treatment outcome in patients treated with Standard Short-Course Chemotherapy for tuberculosis.

BACKGROUNDS: The failure of current Standard Short-Course Chemotherapy (SCC) in new and previously treated cases with tuberculosis (TB) was mainly due to drug resistance development. But little is known on the characteristics of acquired drug resistant TB during SCC and its correlation with SCC failure. The objective of the study is to explore the traits of acquired drug resistant TB emergence and evaluate their impacts on treatment outcomes. METHODS: A prospective observational study was performed on newly admitted smear positive pulmonary TB (PTB) cases without drug resistance pretreatment treated with SCC under China's National TB Control Program (NTP) condition from 2008 to 2010. Enrolled cases were followed up through sputum smear, culture and drug susceptibility testing (DST) at the end of 1, 2, and 5 months after treatment initiation. The effect factors of early or late emergence of acquired drug resistant TB , such as acquired drug resistance patterns, the number of acquired resistant drugs and previous treatment history were investigated by multivariate logistic regression; and the impact of acquired drug resistant TB emergence on treatment failure were further evaluated. RESULTS: Among 1671 enrolled new and previously treated cases with SCC, 62 (3.7%) acquired different patterns of drug resistant TB at early period within 2 months or later around 3-5 months of treatment. Previously treated cases were more likely to develop acquired multi-drug resistant TB (MDR-TB) (OR, 3.8; 95%CI, 1.4-10.4; P = 0.015). Additionally, acquired MDR-TB cases were more likely to emerge at later period around 3-5 months after treatment starting than that of non-MDR-TB mainly appeared within 2 months (OR, 8.3; 95%CI, 1.7-39.9; P = 0.008). Treatment failure was associated with late acquired drug resistant TB emergence (OR, 25.7; 95%CI, 4.3-153.4; P < 0.001) with the reference of early acquired drug resistant TB emergence. CONCLUSIONS: This study demonstrates that later development of acquired drug resistant TB during SCC is liable to suffer treatment failure and acquired MDR-TB pattern may be one of the possible causes.

A pragmatic randomized controlled trial to evaluate the efficacy and safety of an oral short-course regimen including bedaquiline for the treatment of patients with multidrug-resistant tuberculosis in China: study protocol for PROSPECT.

INTRODUCTION: The lack of safe, effective, and simple short-course regimens (SCRs) for multidrug-resistant/rifampicin-resistant tuberculosis (MDR/RR-TB) treatment has significantly impeded TB control efforts in China. METHODS: This phase 4, randomized, open-label, controlled, non-inferiority trial aims to assess the efficacy and safety of a 9-month all-oral SCR containing bedaquiline (BDQ) versus an all-oral SCR without BDQ for adult MDR-TB patients (18-65 years) in China. The trial design mainly mirrors that of the "Evaluation of a Standardized Treatment Regimen of Anti-Tuberculosis Drugs for Patients with MDR-TB" (STREAM) stage 2 study, while also incorporating programmatic data from South Africa and the 2019 consensus recommendations of Chinese MDR/RR-TB treatment experts. Experimental arm participants will receive a modified STREAM regimen C that replaces three group C drugs, ethambutol (EMB), pyrazinamide (PZA), and prothionamide (PTO), with two group B drugs, linezolid (LZD) and cycloserine (CS), while omitting high-dose isoniazid (INH) for confirmed INH-resistant cases. BDQ duration will be extended from 6 to 9 months for participants with Mycobacterium tuberculosis-positive sputum cultures at week 16. The control arm will receive a modified STREAM regimen B without high-dose INH and injectable kanamycin (KM) that incorporates experimental arm LZD and CS dosages, treatment durations, and administration methods. LZD (600 mg) will be given daily for ≥ 24 weeks as guided by observed benefits and harm. The primary outcome measures the proportion of participants with favorable treatment outcomes at treatment completion (week 40), while the same measurement taken at 48 weeks post-treatment completion is the secondary outcome. Assuming an α = 0.025 significance level (one-sided test), 80% power, 15% non-inferiority margin, and 10% lost to follow-up rate, each arm requires 106 participants (212 total) to demonstrate non-inferiority. DISCUSSION: PROSPECT aims to assess the safety and efficacy of a BDQ-containing SCR MDR-TB treatment at seventeen sites across China, while also providing high-quality data to guide SCRs administration under the direction of the China National Tuberculosis Program for MDR-TB. Additionally, PROSPECT will explore the potential benefits of extending the administration of the 9-month BDQ-containing SCR for participants without sputum conversion by week 16. TRIAL REGISTRATION: ClinicalTrials.gov NCT05306223. Prospectively registered on 16 March 2022 at https://clinicaltrials.gov/ct2/show/NCT05306223?term=NCT05306223&draw=1&rank=1 {2}.

Pooled sputum testing by Xpert® MTB/RIF Ultra for active tuberculosis case finding among high-risk groups in a low-incidence area: a prospective study.

BACKGROUND: Early detection and treatment of tuberculosis (TB) are of great importance to stop its spread. However, optimising the active case findingstrategy is critical to improving its feasibility in regions where TB is epidemic. METHOD: The different pooled ratios between TB-positive and TB-negative sputum specimens were evaluated and a pooling ratio of 5:1 was used for the active case finding screening by Xpert MTB/RIF Ultra among high-risk groups in Beijing. RESULTS: The sensitivity of pooling ratio at 5:1 was 97.5% (39/40). Between October 2022 and March 2023, among 17,681 participants, 1729 metthe active case finding criteria and were screened by 350 5:1 sputum pools by Xpert MTB/RIF Ultra. Four pools (1.1%) tested positive and were further confirmed as definite active TB cases. In our study population with high TB incidence (231/100,000), the cost for detection of individual patients was reduced by 77.4% at a 5:1 pooling ratio. CONCLUSIONS: pooled sputum testing at a suitable ratio using Xpert MTB/RIF Ultra provides a rapid, efficient, and cost-effective method for active TB case finding among high-risk groups in a low-incidence area.

[Analysis of the antimycobacterial activities of rifabutin and the relationship between drug-resistance and rpoB mutations of Mycobacterium tuberculosis].

OBJECTIVE: To compare the antimycobacterial activities of rifampicin (RFP) and rifabutin (RBT), and to evaluate the correlation between RBT resistance and genetic alterations in the rpoB gene. METHODS: The microplate-based alamar blue assay (MABA) method was performed to detect the antimycobacterial activities of RFP and RBT in 168 strains of Mycobacterium tuberculosis (M. tuberculosis). Meanwhile, we also analyzed the 81 bp core region of rpoB gene by DNA sequencing. The rate of gene mutations was analyzed by chi-square test. RESULTS: RBT was sensitive for all of the 66 RFP-sensitive strains with no mutations in 81 bp core region of rpoB gene. But of the 102 RFP-resistant strains, 76 strains were also resistant to RBT. Cross resistance between RFP and RBT was 74.5% (76/102). Alterations at codons 516, 526, 531 in the rpoB gene correlated with resistance to both RFP and RBT. While point mutations at codons 511 and 533 possibly influenced the susceptibility to RFP but not to RBT. The mutation rate (92.1%, 70/76) of rpoB gene of RBT-resistant strains was significantly higher than that (23.9%, 22/92) of RBT-sensitive strains (χ(2) = 78.12, P < 0.05). CONCLUSIONS: RBT was more active against M. tuberculosis as compared to RFP. The RFP-resistant strains with MIC ≤ 4 mg/L were still susceptible to RBT. Our results suggest that analysis of genetic alterations in the rpoB gene is useful for predicting RFP-resistance, and may have implications for evaluating RBT-resistance.

Transcription Coactivator BCL3 Acts as a Potential Regulator of Lipid Metabolism Through the Effects on Inflammation.

BACKGROUND AND PURPOSE: Transcriptional coactivator B-cell lymphoma-3 (BCL3) is a member of the IκB family of NF-κB inhibitors and regulates the activity of the NF-κB pathway. However, the relationship between BCL3 and lipid metabolism remains unclear. The present study investigates the effects of BCL3 in immune and metabolism in obese mice. ANIMALS AND METHODS: Construct Bcl3-KO mice through CRISPR/Cas9 technology. Obesity model was induced in Bcl3-KO mice by feeding a high-fat diet for 16 weeks, and some metabolic-related indicators were analysed. RESULTS: The results showed that the KO mice gained significantly less body weight on a high fat diet without a change in food intake. There was significant improvement in hepatic steatosis and adipose tissue hypertrophy in KO mice. The expression of SREBP1 and its downstream fatty acid synthetase FAS and ACC were down-regulated in KO mice, and the inflammation in adipose tissue and liver was further reduced. CONCLUSION: These results suggest that BCL3 may be a novel factor in regulating lipid metabolism in the development of obesity.

Effects of IL-33 on 3T3-L1 cells and obese mice models induced by a high-fat diet.

Obesity is a syndrome that attributes to many factors such as genetics, diet, lifestyle and environment, which includes an imbalance of immune regulation. IL-33, as a new member of the IL-1 family, is classically associated with type 2 immune responses. Here, IL-33 was investigated for its ability to optimize lipid aggregation and ameliorate the inflammatory response in obesity. In vitro experimental results showed that, compared with the induction group, the treatment with 30 ng/mL IL-33 displayed a reduction in the number of lipid droplets. The expression levels of AceCS1 and PPARγ also decreased in the 30 ng/mL IL-33 group compared to the induction group. For confirmation in vivo, three groups of C57BL/6 mice were treated for 14 weeks: mice in control were fed with a normal diet; mice in the HFD and IL-33 groups were fed with a high-fat diet (HFD) and with sterile PBS or recombinant IL-33, respectively. Liver, muscle, spleen and four types of adipose tissue, as well as serum, were collected for further testing. Our data demonstrated that after 4-week treatment with recombinant IL-33, metabolic parameters in mice were improved significantly (visceral fat weight, glucose and insulin tolerance, liver steatosis, expression of lipid synthesis index and inflammatory response). Moreover, IL-33 treatment regulated the original distribution of IL-33 among different tissues. Hence, IL-33 modulated lipid metabolism and inflammatory response in obesity, which would be a novel therapeutic target for obesity and related metabolic diseases.

Acquisition of clofazimine resistance following bedaquiline treatment for multidrug-resistant tuberculosis.

OBJECTIVES: We described the prevalence of clofazimine (CFZ) resistance in a multidrug-resistant tuberculosis (MDR-TB) cohort in China. We also aimed to identify dynamic changes in CFZ susceptibility and its molecular mechanism after exposure to bedaquiline (BDQ) and/or CFZ. METHODS: The experimental settings were conducted based on our MDR-TB cohort receiving BDQ-containing regimens. Sequential isolates were obtained from patients. CFZ and BDQ susceptibility of isolates were determined using the minimum inhibitory concentration (MIC) method. The fragments of Rv0678 and pepQ were sequenced. RESULTS: A total of 277 patients infected with MDR-TB were included in our study. CFZ resistance was noted in 23 (23/277, 8.3%) isolates. The rate of acquired CFZ resistance (12/189, 6.3%) was significantly greater than that of primary resistance (11/88, 12.5%, P = 0.028). Out of 23 CFZ-resistant isolates, five (5/23) were BDQ-resistant, and the other 18 (18/23) were susceptible to BDQ. Of note, nine 9/23) out of 23 CFZ-resistant isolates had mutations within either target genes. Kaplan-Meier analysis demonstrated that the baseline CFZ resistance had no influence on time to culture conversion in our cohort (P = 0.828). Acquired CFZ resistance emerged in eight (8/94, 8.5%) patients during treatment for MDR-TB, including three patients receiving regimens without CFZ. CONCLUSIONS: Our results demonstrate the high rate of CFZ resistance among MDR-TB patients in China. Patients treated with BDQ-containing regimens achieve comparative culture conversion rate regardless of baseline CFZ susceptibility. The presence of acquired CFZ-resistance following BDQ treatment without known mutation indicates that other mechanisms conferring cross resistance to these two compounds may exist.