Project description:To investigate the intestinal ileum response to dietary tryptophan deficiency and the contribution of the intestinal microbiome in regulating these responses
Project description:To understand how cholera toxin (CT) produced by Vibrio cholerae modulates gene expression of this organism within the intestine, RNA-seq analysis was performed on two samples each of WT and the ∆ctx mutant bacteria harvested from either the infant rabbit ileum or the cecum one-day post-intragastric infection. We found that 243 genes that were significantly up-regulated in the WT compared to the ∆ctx mutant and these included 101 genes in ileum samples, 118 in the cecum samples, and 24 in both samples. We found that genes known to be induced under low-iron growth conditions were up-regulated in WT relative to the ∆ctx mutant in both the ileum and in the cecum, with a marked up-regulation in the ileum relative to the cecum. We also found that genes involved in TCA cycle metabolism, L-Lactate utilization, and LCFA utilization were significantly up-regulated in the WT in the ileum relative to the ∆ctx mutant during infection. We conclude that CT-induced disease creates an iron-depleted metabolic niche in the gut that modulates the transcriptional profile of this pathogen during infection.
Project description:To increase our knowledge of the effects of Fructo oligosaccharides (FOS) on the intestinal barrier function in rats, a controlled rat infection study was performed. Two groups of rats (n=12 per group) were adapted to a diet with or without FOS. mRNA was collected from the mucosa of the cecum and changes in gene expression were assessed using an agilent rat whole genome microarray (G4131A Agilent Technologies). Results indicate that dietary FOS influences immune response and wound healing mechanisms, which will most likely affect the intestinal barrier. Keywords: Dietary treatment, cecum mucosa, Rat
Project description:Patient-derived xenografts (PDX) and organoids (PDO) have been shown to model clinical response to cancer therapy. However, it remains challenging to use these models to guide timely clinical decisions for cancer patients. Here we used droplet emulsion microfluidics with temperature control and dead-volume minimization to rapidly generate thousands of Micro- Organospheres (MOS) from low-volume patient tissues, which serve as an ideal patient-derived model for clinical precision oncology. A clinical study of newly diagnosed metastatic colorectal cancer (CRC) patients using a MOS-based precision oncology pipeline reliably predicted patient treatment outcome within 14 days, a timeline suitable for guiding treatment decisions in clinic. Furthermore, MOS capture original stromal cells and allow T cell penetration, providing a clinical assay for testing immuno-oncology (IO) therapies such as PD-1 blockade, bispecific antibodies, and T cell therapies on patient tumors.
Project description:Canonical Wnt signaling controls proliferation and differentiation of osteogenic progenitor cells, and tumor-derived secretion of the Wnt antagonist Dickkopf-1 (Dkk1) is correlated with osteolyses and metastasis in many bone malignancies. However, the role of Dkk1 in the oncogenesis of primary osteosarcoma (OS) remains unexplored. Here, we over-expressed Dkk1 in the OS cell line MOS-J. Contrary to expectations, Dkk1 had autocrine effects on MOSJ cells in that it increased proliferation and resistance to metabolic stress in vitro. In vivo, Dkk1 expressing MOS-J cells formed larger and more destructive tumors than controls. These effects were attributed in part to up-regulation of the stress response enzyme and cancer stem cell marker aldehyde-dehydrogenase-1 (ALDH1) through Jun-N-terminal kinase signaling. This is the first report linking Dkk1 to tumor stress resistance, further supporting the targeting of Dkk1 not only to prevent and treat osteolytic bone lesions but also to reduce numbers of stress-resistant tumor cells. Two samples were analyzed, one human DKK1 transfected MOS-J cell sample and one control vector transfected MOS-J cell sample.
Project description:Regnase-1 plays essential roles in restricting inflammation by acting as a RNase degrading mRNAs involved in immune reactions via the recognition of stem-loop structures in the 3’untranslated regions (UTRs). Dysregulated expression of Regnase-1 is implicated in the pathogenesis of inflammatory and autoimmune diseases in mice and humans. Here we developed a novel therapeutic strategy to suppress inflammatory responses by blocking Regnase-1 self-regulation, which was enabled by the simultaneous use of two antisense phosphorodiamidate morpholino oligonucleotides (MOs) to alter the binding affinity of Regnase-1 towards the stem-loop structures present in its 3’UTR. The Regnase-1-targeting MOs successfully stabilized Regnase-1 mRNA expression. Furthermore, increasing the abundance of Regnase-1 by MO treatment effectively reduced multiple pro-inflammatory transcripts that were controlled by Regnase-1 in BMDMs. Collectively, these data suggested that MO-mediated disruption of the Regnase-1 self-regulation pathway is an attractive therapeutic strategy to enhance Regnase-1 abundance, which could provide clinical benefits for treating inflammatory diseases through the suppression of inflammation.
Project description:After 2 months arsenic exposure, among the 33,492 surveyed genes, 13,005 genes were detected with expression (mean FPKM > 1) in 27 samples of the intestinal tracts (ileum, cecum, and colon) of control and test mice. Among the detected genes, and in comparison to the control and test mice, 328, 579 and 90 dierentially expressed genes (DEGs) were obtained from ileum, cecum, and colon, respectively (FDR < 0.05, Log2 Fold Change > 1). To explore the potential functions of DEGs in the three intestines, we performed GO and KEGG pathway enrichment analysis. Analysis revealed by machine learning of the transcriptome results showed that significantly affected the gene network of pathways related to disease and immunity in the intestine. The results demonstrated that food arsenicals change the intestinal transcriptome significantly, suggest that the host genes might participate in arsenical biotransformation.