Project description:Purpose: To understand how loss of epithelial Smad4 alters gene expression in mouse colon stroma Methods: To understand the extent of Smad-mediated gene regulation in the colon, we isolated colon epithelium from three Smad4ΔLrig1 and from three SMAD4+ control mice (either mice lacking a CreERT allele and treated with tamoxifen, or mice bearing a CreERT allele but treated with vehicle only) and analyzed the colonic stroma by RNAseq. Results: A comparison of gene expression within the sub-epithelial stroma of Smad4Lrig1 mice relative to SMAD4+ control mice demonstrated a marked increase in inflammatory gene signaling. Of the 95 genes that were upregulated by at least 2.5-fold (≥1.32 Log2 Fold Change) and a false discovery rate <0.05, 51 genes are known to be expressed on immune cells or have immune-related functions, including Ccr6. Conclusions: SMAD4 modulates inflammatory signaling in colonic stroma to repress colitis-associated tumor formation
Project description:This RNA seq experiment was designed to identify a gene signature of a CCR5-expressing subset of human intestinal Th17-cells. T helper-cells from peripheral blood of healthy donors and from the lamina propria of Crohn’s Disease patients were FACS-purified according to the expression of the chemokine receptors CCR6, CCR5 and CXCR3. Four CCR6+Th- subsets were isolated according to CXCR3 and CCR5 expression: two CXCR3- Th17 subsets (CCR5-: “cTh17” or CCR5+: “pTh17”) and two subsets of CXCR3+ Th1/17-cells (CCR5+ or CCR5-)
Project description:To detect the miRNA expression profile in CCR6+ regulatory T cells In this study, the total RNA was extracted from CCR6+ regulatory T cells and CCR6- regulatory T cells. Then, the expression profile of miRNA on these cells was detected by microarray.
Project description:To understand the extent of Smad-mediated gene regulation in the colon, we isolated colon epithelium from Smad4ΔLrig1 and from Smad4+ control mice (either mice lacking a CreERT allele and treated with tamoxifen, or mice bearing a CreERT allele but treated with vehicle only) and analyzed the colonic epithelium by RNAseq. The ability of TGFβ1 and/or BMP2 to block TNF-mediated induction of Ccl20 from our study suggests that these Smad-mediated pathways may act as gatekeepers for induction of other inflammation-associated genes. To determine if Smad-mediated signaling blocks all or specific subsets of TNF-induced genes, we analyzed both colonocytes and mouse colonoid treated with or without TNF, TGFβ1, and BMP2 by RNA seq.
Project description:We previously reported that CCR4+CCR6+Th17 cells are permissive to HIV, while CXCR3+CCR6- Th1 cells are relatively resistant. To identify molecular mechanisms underlying these differences, we performed a genome-wide transcriptional profiling in CXCR3+CCR6-Th1, CCR4+CCR6-Th2, CCR4+CCR6+Th17, and CXCR3+CCR6+Th1Th17 upon TCR triggering. Transcriptional differences between Th17 and Th1 were the most remarkable. HIV-DNA integration was highly efficient in Th17 versus Th1 upon exposure to both wild-type and VSV-G-pseudotyped HIV, indicative that post-entry mechanisms contribute to HIV permissiveness. 4 cell populations from up to 5 donors for a total of 19 samples.
Project description:Microarray was used to determine transcriptional differences between Nr1d1+/+ CCR6+ ILC3s and Nr1d1-/- CCR6+ ILC3s isolated from small intestine lamina propria
Project description:We previously reported that CCR4+CCR6+Th17 cells are permissive to HIV, while CXCR3+CCR6- Th1 cells are relatively resistant. To identify molecular mechanisms underlying these differences, we performed a genome-wide transcriptional profiling in CXCR3+CCR6-Th1, CCR4+CCR6-Th2, CCR4+CCR6+Th17, and CXCR3+CCR6+Th1Th17 upon TCR triggering. Transcriptional differences between Th17 and Th1 were the most remarkable. HIV-DNA integration was highly efficient in Th17 versus Th1 upon exposure to both wild-type and VSV-G-pseudotyped HIV, indicative that post-entry mechanisms contribute to HIV permissiveness.
Project description:Antiretroviral therapy (ART) has the potency of suppressing systemic viral replication and spread. Still, persistent human immunodeficiency virus type-1 (HIV) survive for decades during treatment in latently infected cells, making up the latent viral reservoir. This reservoir is believed to reside in subtypes of memory T cells and cell from monocytic lineages, but some functional and naïve T cells have also shown to carry latent HIV. Eradication of latently infected cells, in terms of a sterilizing cure, have proven to be a hurdle since there is a heterogeneity in mechanisms governing latency and integration site into the genome. Over the course of suppressive therapy, persisting HIV, sustained by low levels of viral replication, homeostatic proliferation, and cell to cell transmission, is a driver of chronic immune activation in the body. For the immune system to elicit an appropriate inflammatory response it is dependent on secretion of inflammatory molecules, such as chemokines and cytokines. Most chemokines are pro-inflammatory factors that facilitate leukocyte recruitment to site of inflammation where they can exert their regulatory role in response to pathological and physiological stressors e.g., infection, inflammation, and tissue damage. Alterations in chemokine receptor expression and chemokine levels modulates the activity of the immune response and in HIV infection contribute to chronic inflammation and mortality. Therefore, people living with HIV on suppressive therapy (PLWH) are at higher risk of age associated co-morbidities due to elevated immune activation and chronic inflammation induced by ART toxicities, microbiome dysbiosis leading to microbial translocation and dysregulated immune cell activation and function. As a result, the causative HIV pathogenesis and immune dysfunction further chronic immune activation. This result in a vicious cycle as immune activation is driver of HIV disease progression and inflammaeging leading to earlier onset of age-related diseases. An alternative approach in cure strategies is a functional cure for HIV aiming at suppressing viral replication without ART. A model for functional cure studies are elite controllers (EC). EC constitute a small fraction of HIV+ individuals (<0.5%) exhibiting the unique characteristic of natural control of viral replication in absence of ART. However, there is a population-based heterogeneity of how these individuals naturally supress viral replication. This heterogeneity is caused by viral genetic factors, variability of integration site in the human genome, together with host response against the pathogen and immunological factors. In terms of immune cell activation, studies have shown how EC maintain lower levels of inflammatory markers compared to PLWH. Contradictory, some studies have shown elevated inflammatory markers in EC which could be attributed to the heterogeneity of the EC group or as others have shown it is a consequence of loss of spontaneous control of HIV. Therefore, as no consensus exist further studies comparing variability of immune function between EC and ART can aid in understanding the mechanisms of natural control of HIV. In our recent study (Sperk et al 2021, iScience) we hypothesised that modulated CCR6/CCL20 chemokine axis and CCR2-CCL7-CCL2 signalling can play a protective role in the EC phenotype. Downregulation of CCR2 and CCR6 receptors in lymphocytes and higher plasma abundance of CCL4, CCL7 and CCL20 in EC compared to the HIV-negative controls can provide natural resistance to HIV-infection. In the present study, we further extended our analysis to evaluate the expression profile dynamics of key chemokine receptors, CCR2, CCR3, CCR5 and CCR6, in successfully treated PLWH. We compared well treated PLWH with HIV-1 elite controllers and its association with HIV-1 persistence. Furthermore, cell populations of interest were isolated for liquid chromatography mass spectrometry (LC-MS/MS) based untargeted proteomics analysis to evaluate specific characteristics regulating these cell populations and their role in HIV persistence. Our study provides important understanding of the chemokine receptor dynamics and its role in HIV persistence that differentiate elite controllers from long term treated PLWH.
Project description:Inactivation of TGF-beta family signaling is implicated in colorectal tumor progression. Using the cis-Apc/Smad4 mutant mice, a model of invasive colorectal cancer whose TGF-beta family signaling is blocked, we demonstrate here that a novel type of immature myeloid cells (iMCs) is recruited from the bone marrow to the tumor invasion front. These CD34+ iMCs express MMP9/2 and CC-chemokine receptor 1 (CCR1), and migrate toward its ligand CCL9. In the adenocarcinomas, expression of CCL9 is increased in the tumor epithelium. Such changes in the chemokine expression or the CD34+ iMC recruitment are not observed in the Apc (+/–) mice, a model of adenomatous polyposis. By knocking out Ccr1 gene in the cis-Apc/Smad4 mutant mice, we further demonstrate that lack of CCR1 prevents the accumulation of CD34+ iMCs at the invasion front and suppresses tumor invasion. These results indicate that loss of the TGF-beta family signaling in tumor epithelium causes accumulation of iMCs that help tumor invasion. Keywords: disease state analysis