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.
View Article and Find Full Text PDFBackground: The efficacy of bioresorbable vascular scaffolds (BVS) compared to metallic stents for the treatment of coronary heart disease remains controversial. The analysis of clinical outcomes at five years following the initial treatment has yet to be reviewed. This study sought to assess the five-year outcomes in randomized controlled trials of BVS in the treatment of coronary heart disease using a systematic review and meta-analysis.
View Article and Find Full Text PDFThe blockade of programmed death-ligand 1 (PD-L1) pathway has been clinically used in cancer immunotherapy, while its effects on infectious diseases remain elusive. Roles of PD-L1 signaling in the macrophage-mediated innate immune defense against M.tb is unclear.
View Article and Find Full Text PDFAnimal Model Exp Med
December 2024
Background: The continuing emergence of influenza virus has highlighted the value of public databases and related bioinformatic analysis tools in investigating transcriptomic change caused by different influenza virus infections in human and animal models.
Methods: We collected a large amount of transcriptome research data related to influenza virus-infected human and animal models in public databases (GEO and ArrayExpress), and extracted and integrated array and metadata. The gene expression matrix was generated through strictly quality control, balance, standardization, batch correction, and gene annotation.
CRISPR screening, including CRISPR interference (CRISPRi) and CRISPR-knockout (CRISPR-KO) screening, has become a powerful technology in the genetic screening of eukaryotes. In contrast with eukaryotes, CRISPR-KO screening has not yet been applied to functional genomics studies in bacteria. Here, we constructed genome-scale CRISPR-KO and also CRISPRi libraries in (Mtb).
View Article and Find Full Text PDFAngiotensin-converting enzyme 2 (ACE2) is required for the cellular entry of the severe acute respiratory syndrome coronavirus 2. ACE2, via the Ang-(1-7)-Mas-R axis, is part of the antihypertensive and cardioprotective effects of the renin-angiotensin system. We studied hospitalized COVID-19 patients with hypertension and hypertensive human(h) ACE2 transgenic mice to determine the outcome of COVID-19 with or without AT1 receptor (AT1R) blocker treatment.
View Article and Find Full Text PDFGenetic changes are difficult to reverse; thus, epigenetic aberrations, including changes in DNA methylation, histone modifications, and noncoding RNAs, with potential reversibility, have attracted attention as pharmaceutical targets. The current paradigm is that histone deacetylases (HDACs) regulate gene expression via deacetylation of histone and nonhistone proteins or by forming corepressor complexes with transcription factors. The emergence of epigenetic tools related to HDACs can be used as diagnostic and therapeutic markers.
View Article and Find Full Text PDFZhongguo Yi Xue Ke Xue Yuan Xue Bao
June 2021
Objective To establish a mouse model of exogenous iron overload combined with tuberculosis(TB). Methods C57BL/6N mice were divided into negative control, low-, medium-, and high-dose iron groups and received intraperitoneal injection of iron dextran at 0, 3.75, 7.
View Article and Find Full Text PDFNPJ Vaccines
January 2021
Bacillus Calmette-Guérin (BCG), the only vaccine proven to be effective against tuberculosis (TB), is the most commonly used vaccine globally. In addition to its effects on mycobacterial diseases, an increasing amount of epidemiological and experimental evidence accumulated since its introduction in 1921 has shown that BCG also exerts non-specific effects against a number of diseases, such as non-mycobacterial infections, allergies and certain malignancies. Recent Corona Virus Disease 2019 (COVID-19) outbreak has put BCG, a classic vaccine with significant non-specific protection, into the spotlight again.
View Article and Find Full Text PDFclinical strains usually possess traits different from the laboratory strains like H37Rv, especially those clinical drug resistant strains. With whole genome and transcriptome sequencing, we depicted the feature of two multi-drug resistant Mtb strains in resistance and virulence. Compared with H37Rv, the differential expressed genes (DEGs) of the MDR strains showed featured enrichment in arginine biosynthesis, fatty acid biosynthesis, and metabolism pathway.
View Article and Find Full Text PDFGPR183/EBI2 is a key chemotactic receptor for the positioning of B cells in lymphoid organs, and also for the migration of T cells and other immune cells. Here, we demonstrate that the downregulation of GPR183 in macrophage induced during Mtb infection restrains the bacterial early infection and intracellular replication. Overexpression of GPR183 or stimulation with its natural ligand favors Mtb replication in macrophage, while treatment with its antagonist represses both Mtb early infection and intracellular replication.
View Article and Find Full Text PDFEur J Clin Microbiol Infect Dis
August 2020
Bacillus Calmette-Guérin (BCG) has been in use for nearly 100 years and is the only licensed TB vaccine. While BCG provides protection against disseminated TB in infants, its protection against adult pulmonary tuberculosis (PTB) is variable. To achieve the ambitious goal of eradicating TB worldwide by 2050, there is an urgent need to develop novel TB vaccines.
View Article and Find Full Text PDFTuberculosis (TB), caused by () bacteria, is a leading infectious cause of mortality worldwide. The emergence of drug-resistant has made control of TB more difficult. The selective optimization of side activities (SOSA) approach uses old drugs for new pharmacological targets.
View Article and Find Full Text PDFAccumulating evidence suggests important functions for human Toll-like receptor 8 in tuberculosis and autoimmune diseases. However, these studies are limited by the lack of specific agonists and by the fact that the homology of TLR8 in human and mice is not sufficient to rely on mouse models. In this study, we examined the role of human TLR8 in the disease progression of experimental infection, as well as the benefits provided by a TLR8 agonist against challenge in a human transgenic mouse.
View Article and Find Full Text PDFTuberculosis (TB) is a health threat to the global population. Anti-TB drugs and vaccines are key approaches for TB prevention and control. TB animal models are basic tools for developing biomarkers of diagnosis, drugs for therapy, vaccines for prevention and researching pathogenic mechanisms for identification of targets; thus, they serve as the cornerstone of comparative medicine, translational medicine, and precision medicine.
View Article and Find Full Text PDFA mouse model of spontaneous latent tuberculosis infection (LTBI) that mimics LTBI in humans is valuable for drug/vaccine development and the study of tuberculosis. However, most LTBI mouse models require interventions, and a spontaneous LTBI mouse model with a low bacterial load is difficult to establish. In this study, mice were IV-inoculated with 100 CFU Mycobacterium tuberculosis H37Rv, and a persistent LTBI was established with low bacterial loads (0.
View Article and Find Full Text PDFApoptosis was considered as one of the important host defense mechanisms against mycobacteria infection. In macrophage, the main target cell of Mycobacterium tuberculosis, apoptosis after infection could help kill the bacillus inside and process the antigens for further presentation and proper immune response. Here, we identified a role of TLR8 during the apoptosis induced by Bacillus Calmette Guérin (BCG) infection in THP-1 cells.
View Article and Find Full Text PDFFEMS Microbiol Lett
November 2014
In recent years, the Chinese tree shrew has been considered to be a promising experimental animal for numerous diseases. Yet the susceptibility of Mycobacterium tuberculosis (MTB) in Chinese tree shrew is still unknown. We infected Chinese tree shrews with a high dose (2.
View Article and Find Full Text PDFThe study was to evaluate the long term immunological efficacy of pandemic 2009 H1N1 influenza live virus infection and split vaccine against the homologous virus challenge in ferrets. Antibodies in ferrets were monitored by haemagglutination inhibition (HI) assay for 200 days, the HI titers of both infected-only and vaccinated plus infected ferrets could maintain a high level for at least 182 days, without significant difference between the two infected groups. While one-dose and two-dose vaccinated ferrets could last a moderate antibody titers for 81 days, with its peak value at day 7 post immunization.
View Article and Find Full Text PDFThe real-time PCR diagnostics for avian influenza virus H5N1 in tissue specimens are often suboptimal, since naturally occurring PCR inhibitors present in samples, or unanticipated match of primer to unsequenced species' genome. With the principal aim of optimizing the SYBR Green real-time PCR method for detecting H5N1 in ferret and monkey (Chinese rhesus macaque) tissue specimens, we screened various H5N1 gene-specific primer pairs and tested their ability to sensitively and specifically detect H5N1 transcripts in the infected animal tissues, then we assessed RNA yield and quality by comparing Ct values obtained from the standard Trizol method, and four commonly used RNA isolation kits with small modifications, including Roche High Pure, Ambion RNAqueous, BioMIGA EZgene, and Qiagen RNeasy. The results indicated that a single primer pair exhibited high specificity and sensitivity for H5N1 transcripts in ferret and monkey tissues.
View Article and Find Full Text PDFThe experimental infection of a mouse lung with influenza A virus has proven to be an invaluable model for studying the mechanisms of viral adaptation and virulence. The mouse adaption of human influenza A virus can result in mutations in the HA and other proteins, which is associated with increased virulence in mouse lungs. In this study, a mouse-adapted seasonal H1N1 virus was obtained through serial lung-to-lung passages and had significantly increased virulence and pathogenicity in mice.
View Article and Find Full Text PDFThe novel pandemic A (H1N1) virus was first identified in Mexico in April 2009 and quickly spread worldwide. Like all influenzas, the H1N1 strain-specific properties of replication, virulence, and pathogenicity are a result of the particular genomic sequence and concerted expression of multiple genes. Thus, specific mutations may support increased virulence and may be useful as biomarkers of potential threat to human health.
View Article and Find Full Text PDFBackground: The novel pandemic A (H1N1) virus was first identified in Mexico in April 2009 and since then it spread world wide over a short period of time. Although the virus infection is generally associated with mild disease and a relatively low mortality, it is projected that mutations in specific regions of the viral genome, especially within the receptor binding domain of the hemagglutinin (HA) protein could result in more virulent virus stains, leading to a more severe pandemic.
Results: Here, we found that a single amino acid substitution of Asp-to-Gly at position 222 in the HA protein of the A (H1N1) virus occurred after two passage propagation in the allantoic cavities of chicken embryonated eggs, and this single residue variation dramatically increased the viral replication ability in MDCK cells and pathogenicity in BALB/c mice.