Project description:Among both healthy and immunocompromised patient populations, pneumonia is a leading cause of death worldwide. Yet, despite structural vulnerability resulting in recurrent exposure to pathogens, the lungs’ mucosal immunity successfully suppresses most infections. We recently reported that these innate defenses can be substantially augmented by inhalational exposure to a crude bacterial lysate, protecting broadly against respiratory pathogens, including lethal pneumonia caused by bacteria, fungi or viruses. The phenomenon of inducible resistance is associated with rapid pathogen killing in the lungs and persists in the absence of the typical leukocytes of innate immunity. Rather, the respiratory epithelium appears to be the predominant effector. Toll-like receptors (TLRs) are highly conserved pattern recognition receptors crucial to host defense through the sensing of pathogen associated molecular patterns. Given the importance of TLRs to mucosal immunity, the presence of numerous pathogen associated molecular patterns in the bacterial lysate, and the induction of many TLR-dependent genes following lysate treatment, we hypothesized that induced resistance follows simultaneous stimulation of multiple TLRs. To test this, we challenged mice deficient in TLR/IL1R adaptor proteins and found that resistance could not be induced in mice lacking MyD88. Having identified this phenomenon to be MyD88-dependent, we sought to determine whether the protective phenomenon could be recapitulated by treatment with synthetic TLR agonists. Mice were treated with aerosolized TLR ligands, alone and in combination, prior to infection with virulent pathogens. While limited protection against pneumonia was afforded by the individual TLR ligands, we discovered that the synergistic combination of diacylated lipopetide TLR2/6 agonist Pam2CSK4 and CpG oligodeoxynucleotide TLR9 agonist ODN2395 induced profound resistance against all tested pathogens. This combination also induced greater than additive pathogen killing in the lungs of challenged mice, and we found that the combination could effectively induce pathogen killing by respiratory epithelial cells in vitro. In order to better understand the mechanisms underlying the inducible pathogen killing by this unique combination of TLR agonists, we performed microarray analysis of murine MLE-15 respiratory epithelial cells following 4 h treatment with PBS (sham treatment), Pam2CSK4 alone, ODN2395 alone, or the combination of both agonists, using Illumina Sentrix MouseRef-8 v2 BeadChips. This allows for assessment of differential gene expression, not only between treated and untreated, but between single and combination treated. The intent of the experiment is to gain insight into the transcriptionally-regulated means by which TLR2/6 and TLR9 signaling pathways synergistically interact. Keywords: Differential expression, epithelium, in vitro
Project description:Infectious pneumonias exact an unacceptable mortality burden worldwide. Efforts to protect populations from pneumonia have historically focused on antibiotic development and vaccine-enhanced adaptive immunity. However, we have recently reported that the lungs’ innate defenses can be therapeutically induced by inhalation of a combination of synthetic TLR ligands that synergize to protect mice against otherwise lethal pneumonia. Simultaneous treatment with ligands for TLR2/6 and TLR9 conferred robust, synergistic protection against virulent Gram-positive and Gram-negative pathogens, as well as viruses. Protection is associated with rapid pathogen killing in the lungs, and pathogen killing can be induced from lung epithelial cells in isolation. Here we explore the mechanisms underlying this dramatic phenomenon by performing microarray gene expression analysis of mouse lungs treated by aerosol with PBS (sham treatment), Pam2CSK4 (TLR 2/6 ligand), ODN2395 (TLR9 ligand), or both TLR ligands.
Project description:Infectious pneumonias exact an unacceptable mortality burden worldwide. Efforts to protect populations from pneumonia have historically focused on antibiotic development and vaccine-enhanced adaptive immunity. However, we have recently reported that the lungs’ innate defenses can be therapeutically induced by inhalation of a bacterial lysate that protects mice against otherwise lethal pneumonia. Here, we tested in mice the hypothesis that Toll-like receptors (TLRs) are required for this antimicrobial phenomenon, and found that resistance could not be induced in the absence of the TLR signaling adaptor protein MyD88. We then attempted to recapitulate the protection afforded by the bacterial lysate by stimulating the lung epithelium with aerosolized synthetic TLR ligands. While most single or combination treatments yielded no protection, simultaneous treatment with ligands for TLR2/6 and TLR9 conferred robust, synergistic protection against virulent Gram-positive and Gram-negative pathogens. Protection was associated with rapid pathogen killing in the lungs, and pathogen killing could be induced from lung epithelial cells in isolation. Taken together, these data demonstrate the requirement for TLRs in inducible resistance against pneumonia, reveal a remarkable, unanticipated synergistic interaction of TLR2/6 and TLR9, reinforce the emerging evidence supporting the antimicrobial capacity of the lung epithelium, and may provide the basis for a novel clinical therapeutic that can protect patients against pneumonia during periods of peak vulnerability. MLE-15 cells were treated with 20 ul volumes of PBS (sham treatment), ODN2395 (0.4 ug), Pam2CSK4 (0.2 ug) or ODN2395+Pam2CSK4. At least 5 unique samples per group. Treated for 2 hours. Hybridized to Illumina Sentrix MouseRef-8 v2 Beadhips.
Project description:PURPOSE: To provide a detailed gene expression profile of the normal postnatal mouse cornea. METHODS: Serial analysis of gene expression (SAGE) was performed on postnatal day (PN)9 and adult mouse (6 week) total corneas. The expression of selected genes was analyzed by in situ hybridization. RESULTS: A total of 64,272 PN9 and 62,206 adult tags were sequenced. Mouse corneal transcriptomes are composed of at least 19,544 and 18,509 unique mRNAs, respectively. One third of the unique tags were expressed at both stages, whereas a third was identified exclusively in PN9 or adult corneas. Three hundred thirty-four PN9 and 339 adult tags were enriched more than fivefold over other published nonocular libraries. Abundant transcripts were associated with metabolic functions, redox activities, and barrier integrity. Three members of the Ly-6/uPAR family whose functions are unknown in the cornea constitute more than 1% of the total mRNA. Aquaporin 5, epithelial membrane protein and glutathione-S-transferase (GST) omega-1, and GST alpha-4 mRNAs were preferentially expressed in distinct corneal epithelial layers, providing new markers for stratification. More than 200 tags were differentially expressed, of which 25 mediate transcription. CONCLUSIONS: In addition to providing a detailed profile of expressed genes in the PN9 and mature mouse cornea, the present SAGE data demonstrate dynamic changes in gene expression after eye opening and provide new probes for exploring corneal epithelial cell stratification, development, and function and for exploring the intricate relationship between programmed and environmentally induced gene expression in the cornea. Keywords: other
Project description:The aim of this study was to assess whether chronic treatment with RPV can modulate the progression of chronic liver disease, especially of non-alcoholic fatty liver disease (NAFLD), through a nutritional model in wild-type mice Mice were daily treated with RPV (p.o.) and fed with normal or high fat diet during 3 months to induce fatty liver disease
Project description:Infectious pneumonias exact an unacceptable mortality burden worldwide. Efforts to protect populations from pneumonia have historically focused on antibiotic development and vaccine-enhanced adaptive immunity. However, we have recently reported that the lungs’ innate defenses can be therapeutically induced by inhalation of a combination of synthetic TLR ligands that synergize to protect mice against otherwise lethal pneumonia. Simultaneous treatment with ligands for TLR2/6 and TLR9 conferred robust, synergistic protection against virulent Gram-positive and Gram-negative pathogens, as well as viruses. Protection is associated with rapid pathogen killing in the lungs, and pathogen killing can be induced from lung epithelial cells in isolation. Here we explore the mechanisms underlying this dramatic phenomenon by performing microarray gene expression analysis of mouse lungs treated by aerosol with PBS (sham treatment), Pam2CSK4 (TLR 2/6 ligand), ODN2395 (TLR9 ligand), or both TLR ligands. C57BL/6J mice were placed, unrestrained, in a aerosolization chamber and inhalationally exposed to 20 minute treatment with an 8 ml volume of PBS (sham), Pam2CSK4 10 ug/ml, ODN 2395 20 ug/ml, or the combination. 4 h after treatment, the mice were deeply anesthetized, their lungs were harvested, homogenized, and total RNA was extracted. Amplified cRNA was hybridized to Illumina Sentrix MouseRef-8 v2 Beadhips, labeled with Cy3, and scanned on an Illumina iScan. At least 8 unique samples were obtained per condition.