Project description:Experimental screening of a compound library identified a molecule that potently inhibits the growth of the obligate intracellular bacterial pathogen Chlamydia trachomatis in human cells. To identify the molecular target of the compound, three mutant bacterial strains resistant to its inhibitory action were generated by long-term passage in the presence of initially low but increasing concentrations of the molecule. Subsequently, genomic DNA of the three mutant and the wildtype bacteria was isolated and subjected to whole genome sequencing to identify resistance-promoting mutations.
Project description:<p>Chlamydia trachomatis, an intracellular pathogen, is recognized as the most common sexually transmitted bacterial infection among women worldwide. Chlamydia infections can lead to undesirable clinical outcomes, including pelvic inflammatory disease and infertility. Recently, the gut has been identified as a niche for Chlamydia colonization; however, despite the biological impact on the host remaining under investigation, oral inoculation of Chlamydia as a whole-organism vaccine has been reported as a promising strategy for preventing genital Chlamydia infections. Few studies have evaluated the impact of oral Chlamydia vaccination on the gut microbiome and metabolite changes. In this study, we assessed time-series alterations in the gut microbiome and metabolites following oral Chlamydia inoculation, and we analyzed the composition and correlation between serum immune parameters and the sequencing profiles in the host. We identified 129 microbial changes and 186 significantly different metabolites in the gut across various vaccination approaches during the 30-day immunization process. Additionally, we discussed potential biomarkers of effective immunization based on correlation analysis.</p>
Project description:The T cell response to Chlamydia genital tract infections in humans and mice is unusual in that the majority of antigen-specific CD8 T cells are not restricted by HLA/MHC class I and therefore have been referred to as “unrestricted” or “atypical”. We previously reported that a subset of unrestricted murine Chlamydia-specific CD8 T cells had an unusual cytokine polarization pattern that included IFN-ɣ and IL-13. For this report, we investigated the transcriptome of Chlamydia-specific CD8ɣ13 T cells, comparing them to Chlamydia-specific multifunctional Tc1 clones using gene expression micro array analysis. The molecular study revealed that CD8ɣ13 polarization included IL-5 in addition to IFN-γ and IL-13. Adoptive transfer studies were performed with Tc1 clone and CD8ɣ13 T cell clones to determine whether either influenced bacterial clearance or immunopathology during Chlamydia muridarum (Cm) genital tract infections. To our surprise, an adoptively transferred CD8ɣ13 T cell clone was remarkably proficient at preventing chlamydia immunopathology while the multifunctional Tc1 clone did not enhance clearance or significantly protect from immunopathology. Mapping studies with MHC class I- and class II-deficient splenocytes showed our previously published Chlamydia-specific CD8 T cell clones are MHC class II-restricted. MHC class II-restricted CD8 T cells may play important roles in protection from intracellular pathogens that limit class I antigen presentation or deplete the CD4 T cell compartment.
Project description:We applied Formaldehyde-Assisted Isolation of Regulatory Elements enrichment followed by sequencing (FAIRE-Seq) to generate genome-wide temporal chromatin maps of Chlamydia trachomatis-infected human epithelial cells in vitro over the chlamydial developmental cycle. We detected both conserved and distinct temporal regions of chromatin accessibility associated with C. trachomatis infection. The observed differentially accessible chromatin regions, including several Clusters of Open Regulatory Elements (COREs) and temporally-enriched sets of transcription factors, may help shape the host cell response to infection. These regions and motifs were linked to genomic features and genes associated with immune responses, re-direction of host cell nutrients, intracellular signaling, cell-cell adhesion, extracellular matrix, metabolism and apoptosis. This work will serve as a basis for future functional studies of transcriptional regulation and epigenomic regulatory elements in Chlamydia-infected human cells.
Project description:Transcriptional profiling of human epithelial cell line (HL) infected with Chlamydia penumoniae compared to control cells at time points 12h, 24h, 48h, 72h after the infection. Keywords: Chlamydia peneumoniae infection
Project description:Chlamydia trachomatis is an obligate intracellular pathogen that causes trachoma and sextually transmitted disease in human. During early stage of infection, Chlamydia secreted bacterial effector proteins into host cell cytoplasm to help its entry and estabilishment of early replicated niche. We identified a Chlamydia mutant that lack an early Effector. To address the function of this effector, we infected A2EN cells with this mutant (G1V) and its complemented counterpart (G1TEPP) to see what host gene transcriptions are affected by this effector. A2EN cells were mock infected, or infected with a Chlamydia mutant or its complemented counterpart for 4 hour post infection.
Project description:The overall study examines the mechanism and role of innate re-stimulation of T cells after activation and differentiation during infection. This particular study is focused on the restimulation of Th1 cells activated during Chlamydia infection, using in vivo LPS stimulation to increase the response. The study was conducted to compare the expression profile after LPS stimulation during Chlamydia infection to that seen after LPS stimulation during Salmonella infection (submitted as a separate dataset).