Effect of Mn2+@Man-phage on gene expression in RAW264.7 macrophages
Ontology highlight
ABSTRACT: Bacterial infectious diseases have posed a serious challenge to public health, often resulting in treatment failure and infection recurrence due to the emergence of drug-resistant bacteria. Owing to inaccessible binding sites, pathogens can evade attack from host immune cells and traditional antibiotics, leading to local immunosuppressive status. Our study reports a novel bacteriophage-based immune scavenger labeling nanoplatform (Mn2+@Man-phage) to combat immune-evasive bacteria and reverse immunosuppressive status. Our nanosystem utilizes the inherent bacterium-targeting ability of bacteriophages to aggregate at infection sites and mediates mannose-dependent recognition, phagocytosis, and killing of bacteria by macrophages, while the released Mn2+ amplifies the antibacterial immune efficacy. Consequently, macrophages polarize towards M1 and secrete various pro-inflammatory factors, effectively clearing bacteria. Moreover, reprogramming macrophages directly activate T cells at infection sites, eliciting potent adaptive antibacterial immune responses and ultimately achieving bacterial eradication. Overall, we demonstrate a universal strategy for pathogen targeting and immunomodulation of macrophages against bacterial infection.
Project description:Bacterial infectious diseases have posed a serious challenge to public health, often resulting in treatment failure and infection recurrence due to the emergence of drug-resistant bacteria. Owing to inaccessible binding sites, pathogens can evade attack from host immune cells and traditional antibiotics, leading to local immunosuppressive status. Our study reports a novel bacteriophage-based immune scavenger labeling nanoplatform (Mn2+@Man-phage) to combat immune-evasive bacteria and reverse immunosuppressive status. Our nanosystem utilizes the inherent bacterium-targeting ability of bacteriophages to aggregate at infection sites and mediates mannose-dependent recognition, phagocytosis, and killing of bacteria by macrophages, while the released Mn2+ amplifies the antibacterial immune efficacy. Consequently, macrophages polarize towards M1 and secrete various pro-inflammatory factors, effectively clearing bacteria. Moreover, reprogramming macrophages directly activate T cells at infection sites, eliciting potent adaptive antibacterial immune responses and ultimately achieving bacterial eradication. Overall, we demonstrate a universal strategy for pathogen targeting and immunomodulation of macrophages against bacterial infection.
Project description:The skin is the human body’s largest organ and is in contact with a diverse community of microorganisms that includes both resident and pathogenic bacteria. Skin immune defenses include the production of antimicrobial proteins that kill bacteria directly. However, we still have an incomplete understanding of how skin antimicrobial proteins promote homeostasis with resident bacterial communities and limit infection. Here, we show that resistin-like molecule α (RELMα) is an antibacterial protein that is produced by keratinocytes and sebocytes in the mouse skin. RELMα expression was induced in mouse skin by resident and pathogenic skin bacteria and was bactericidal for several bacterial species found on the skin, including Streptococcus pyogenes. Mice lacking RELMα had altered resident skin bacterial communities and were more susceptible to bacterial infection, indicating that RELMα controls bacterial colonization of the skin. RELMα expression required dietary vitamin A and could be induced by therapeutic retinoids that protected against bacterial infection in a RELMα-dependent manner. Resistin, another member of the RELM family, was expressed in human skin, required retinoids for expression, and killed skin bacteria, indicating a conserved function for RELM proteins in skin innate immunity. Our findings thus identify members of the RELM family as antibacterial proteins that provide vitamin A-dependent antimicrobial protection of the skin, and provide insight into why skin immunity requires adequate dietary vitamin A.
Project description:Bacterial resistance has become more and more widespread which seriously threatens human life and health. Therefore, using the natural immune system of host to kill bacteria is particularly fascinating. Here, using mass spectrometry analyses, we depicted the dynamic expression landscape of mitochondria and lysosomes proteins upon five kinds of bacteria (L. monocytogenes, Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa) infection in Macrophages cells. We showed that the protein expression level of Cathepsin D (CTSD) is up-regualated after bacterial infection. The knockout of CTSD indicated that, as a broad-spectrum antibacterial protein in the host, played an indispensable role in killing bacteria. Our study shows that CTSD can serve as a potential molecular drug target for antibacterial treatment.
Project description:Macrophages phagocytose bacteria. Certain pathogenic bacteria access and replicate within the cytosol of infected macrophages and induce changes in macrophage gene expression by triggering of innate immune receptors and/or the effects of bacterial virulence factors. We used microarray analysis to identify changes in macrophage gene expression following infection with Listeria monocytogenes.
Project description:<p>The reverse transsulfuration pathway is the major route for the metabolism of sulfur-containing amino acids. The role of this metabolic pathway in macrophage response and function is unknown. We show that the enzyme cystathionine γ-lyase (CTH) is induced in macrophages infected with pathogenic bacteria through signaling involving phosphatidylinositol 3-kinase (PI3K)/MTOR and the transcription factor SP1. This results in the synthesis of cystathionine, which facilitates the survival of pathogens within myeloid cells. Our data demonstrate that the expression of CTH leads to defective macrophage activation by (i) dysregulation of polyamine metabolism by depletion of S-adenosylmethionine, resulting in immunosuppressive putrescine accumulation and inhibition of spermidine and spermine synthesis, and (ii) increased histone H3K9, H3K27, and H3K36 di/trimethylation, which is associated with gene expression silencing. Thus, CTH is a pivotal enzyme of the innate immune response that disrupts host defense. The induction of the reverse transsulfuration pathway by bacterial pathogens can be considered an unrecognized mechanism for immune escape.</p><p><strong>IMPORTANCE:</strong> Macrophages are professional immune cells that ingest and kill microbes. In this study, we show that different pathogenic bacteria induce the expression of cystathionine γ-lyase (CTH) in macrophages. This enzyme is involved in a metabolic pathway called the reverse transsulfuration pathway, which leads to the production of numerous metabolites, including cystathionine. Phagocytized bacteria use cystathionine to better survive in macrophages. In addition, the induction of CTH results in dysregulation of the metabolism of polyamines, which in turn dampens the proinflammatory response of macrophages. In conclusion, pathogenic bacteria can evade the host immune response by inducing CTH in macrophages.</p>
Project description:Macrophages phagocytose bacteria. Certain pathogenic bacteria access and replicate within the cytosol of infected macrophages and induce changes in macrophage gene expression by triggering of innate immune receptors and/or the effects of bacterial virulence factors. We used microarray analysis to identify changes in macrophage gene expression following infection with Listeria monocytogenes. Experiment Overall Design: Macrophages were cultured from bone marrow of female C57BL/6 mice using 10% L-cell conditioned media and mock infected (3 chips) or infected with log phase L. monocytogenes (2 chips). Samples were harvested for RNA isolation at 10 h after infection. Experiment Overall Design: Supplementary file below reports Genesifter-processed data: mean ("P" only) signal intensities and SEM for the MOCK and LM_INF groups.
Project description:Type I interferons were discovered as the primary antiviral cytokines and are now known to serve critical functions in host defense against bacterial pathogens. Accordingly, established mediators of interferon antiviral activity may mediate previously unrecognized antibacterial functions. RNase-L is the terminal component of an RNA decay pathway that is an important mediator of interferon-induced antiviral activity. Here we identify a novel role for RNase-L in the host antibacterial response. RNase-L-/- mice exhibited a dramatic increase in mortality following challenge with Bacillus anthracis and Escherichia coli; this increased susceptibility was due to a compromised immune response resulting in increased bacterial load. Investigation of the mechanisms of RNase-L antibacterial activity indicated that RNase-L is required for the optimal induction of proinflammatory cytokines that play essential roles in host defense from bacterial pathogens. RNase-L also regulated the expression of the endolysosomal protease, cathepsin-E, and endosome-associated activities, that function to eliminate internalized bacteria and may contribute to RNase-L antimicrobial action. Our results reveal a unique role for RNase-L in the antibacterial response that is mediated through multiple mechanisms. As a regulator of fundamental components of the innate immune response, RNase-L represents a viable therapeutic target to augment host defense against diverse microbial pathogens. two strains: wildtype and knockout, three time points: untreated, 2hours, and 8hours. three replication for each group. Totally 18 samples.
Project description:Due to the rapid emergence of antibiotic-resistant bacteria, there is a growing need to discover antibacterial agents. Herein, we design and synthesize a compound of TPA2PyBu that kills both Gram-negative and Gram-positive bacteria with an undetectably low drug resistance. Comprehensive analyses reveal that the antimicrobial activity of TPA2PyBu proceeds via a unique dual mechanism by damaging bacterial membrane integrity and inducing DNA aggregation. TPA2PyBu could provide imaging specificity that differentiates bacterial infection from inflammation and cancer. Importantly, high in vivo treatment efficacy of TPA2PyBu was achieved in methicillin-resistant S. aureus infection mouse models. This promising antimicrobial agent suggests that combining multiple mechanisms of action into a single molecule can be an effective approach to address challenging bacterial infections.
Project description:Porcine cytomegalovirus (PCMV; genus Cytomegalovirus, subfamily Betaherpesvirinae, family Herpesviridae) is an immunosuppressive virus that mainly inhibits the immune function of T lymphocytes and macrophages, which has caused great distress to the farming industry. In this study, we obtained the miRNA expression profiles of PCMV-infected and control porcine macrophages, PCMV-infected and control porcine tissues via high-throughput sequencing. The comprehensive analysis of miRNA profiles showed that 306 miRNA database annotated and 295 novel pig-encoded miRNAs were detected. Gene Ontology (GO) analysis of the target genes of miRNAs in PCMV infected porcine macrophages showed that the differentially expressed miRNAs are mainly involved in immune and metabolic process. This is the first report of the miRNA transcriptome in PCMV infected porcine macrophages and PCMV infected tissues and the analysis of the miRNA regulatory mechanism during PCMV infection. Further research into the regulatory mechanisms of miRNAs during immunosuppressive viral infections will contribute to the treatment and prevention of immunosuppressive viruses. miRNA expression profiling of PCMV-infected and control porcine macrophages; PCMV-infected and control porcine tissues via high-throughput sequencing.
Project description:Using integrated genomics we identify a role for CLEC12A in antibacterial autophagy. Clec12a-/- mice are more susceptible to bacterial infection and CLEC12A deficient cells exhibit impaired antibacterial autophagy. We used transcriptional profilinf to understand the role of CLEC12A in the response to Salmonella and Listeria. Bone marrow-derived macrophages from WT or Clec12a-/- mice were infected with Salmonella enterica serovar Typhimurium or Listeria monocytogenes. Cells were harvested at 0,3,6, and 24hours post-infection for RNA analysis. Please note that single-end sequencing was performed but two files: R1 files that contained the sample barcodes (19 or 17bp reads) and R2 files that contained the single-end-sequenced 46bp cDNA reads were generated. Since the barcode info is mostly redundant, only R2 reads were submitted (described in 'raw_file_readme.txt').