Project description:Blood monocytes serve as the first line of host defense and are equipped to recognize and respond to infection by triggering an immune-inflammatory response. While most information on these cells comes from in vitro studies in humans or in vivo studies in mice, little is known about monocytes under human disease conditions. We investigated the role of monocytes during sepsis and its resolution in humans. A transcriptomal and functional analysis of blood monocytes from patients during gram negative sepsis and at recovery was performed. Monocytes from sepsis patients showed upregulation of a large number of pro-inflammatory genes and cytokines/chemokines, consistent with an ongoing systemic inflammation. However, these cells showed impairment to ex vivo endotoxin (LPS) challenge, displaying a quantitative decrease in the number of LPS-inducible genes. Moreover, they downregulated the expression of several pro-inflammatory cytokine/chemokine genes, activation marker genes and transcription factors associated with monocyte/macrophage activation, upon ex vivo LPS stimulation. Functionally, they downregulated expression of inflammatory cytokines/chemokines and antigen presentation-related molecules and functions. In contrast, genes and functions related to phagocytosis, anti-microbial activity and tissue remodeling where remained unaffected or even enhanced . Collectively, our observations suggest a genetic and functional re-programming of these cells during human sepsis progression. Understanding the molecular mechanisms which regulate this re-programming will allow to devise strategies which could modulate the response of these cells and hence, disease progression. Blood monocytes from gram-negative sepsis patients during sepsis (Sepsis) and following their recovery (Recovery/Basal) as well as healthy donor (control) were isolated. Thereafter, these cells were treated ex vivo with or without LPS for 3h and analysed for transcriptomic study.
Project description:Blood monocytes serve as the first line of host defense and are equipped to recognize and respond to infection by triggering an immune-inflammatory response. While most information on these cells comes from in vitro studies in humans or in vivo studies in mice, little is known about monocytes under human disease conditions. We investigated the role of monocytes during sepsis and its resolution in humans. A transcriptomal and functional analysis of blood monocytes from patients during gram negative sepsis and at recovery was performed. Monocytes from sepsis patients showed upregulation of a large number of pro-inflammatory genes and cytokines/chemokines, consistent with an ongoing systemic inflammation. However, these cells showed impairment to ex vivo endotoxin (LPS) challenge, displaying a quantitative decrease in the number of LPS-inducible genes. Moreover, they downregulated the expression of several pro-inflammatory cytokine/chemokine genes, activation marker genes and transcription factors associated with monocyte/macrophage activation, upon ex vivo LPS stimulation. Functionally, they downregulated expression of inflammatory cytokines/chemokines and antigen presentation-related molecules and functions. In contrast, genes and functions related to phagocytosis, anti-microbial activity and tissue remodeling where remained unaffected or even enhanced . Collectively, our observations suggest a genetic and functional re-programming of these cells during human sepsis progression. Understanding the molecular mechanisms which regulate this re-programming will allow to devise strategies which could modulate the response of these cells and hence, disease progression.
Project description:In this project we performed a comprehensive exploration of monocyte molecular responses in a cohort of patients with septic shock via label-free shotgun proteomics. We enrolled adult (≥18 years old) patients with sepsis from community-acquired infections, diagnosed according to the Third International Consensus Definitions for Sepsis and Septic Shock (Sepsis-3) criteria. Blood samples were obtained within the first 72 hours from the diagnosis of sepsis (sepsis phase) and on de day before ICU discharge (recovery phase). The Control group consisted of age matched healthy volunteers. We excluded subjects with AIDS, advanced cancer, hematological diseases, and pregnancy.
Project description:Myeloid-derived suppressor cells (MDSCs) are highly immunosuppressive myeloid cells, which increase in cancer patients. The molecular mechanism behind their generation and function is unclear. Whereas granulocytic-MDSCs correlate with poor overall survival in breast cancer, the presence and relevance of monocytic-MDSCs (Mo-MDSCs) is unknown. Here we report for the first time an enrichment of functional blood Mo-MDSCs in breast cancer patients before they acquire a typical Mo-MDSC surface phenotype. A clear population of Mo-MDSCs with the typical cell surface phenotype (CD14+HLA-DRlow/-Co-receptorlow/-) increased significantly first during disease progression and correlated to metastasis to lymph nodes and visceral organs. Furthermore, monocytes, comprising the Mo-MDSC population, from patients with metastatic breast cancer resemble the reprogrammed immunosuppressive monocytes in patients with severe infections, both by their surface and functional phenotype but also at their molecular gene expression profile. Our data suggest that monitoring the Mo-MDSC levels in breast cancer patients may represent a novel and simple biomarker for assessing disease progression. Peripheral blood monocytes were isolated using magnetic cell sorting from 4 patients with metastatic breast cancer, 3 healthy controls, 3 patients with sepsis and 3 patients with active tuberculosis were immediately frozen at -80C in TRIZOL.
Project description:Critical illness and sepsis are characterized by drastic changes in the systemic innate immune response, particularly involving monocytes. Here we prospectively analyzed the gene expression profile of circulating CD14+ monocytes of selected samples by RNA Sequencing.
Project description:Genome wide DNA methylation profiling of monocytes from healthy donors, systemic inflammatory response syndrome (SIRS) and septic patients. The Illumina Infinium MethylationEPIC Beadchip was used to obtain DNA methylation profiles across approximately 850,000 CpGs in CD14+CD66bneg monocytes isolated from PBMCs of 11 healthy donors, 4 SIRS and 14 septic patients.
Project description:We sequenced and analyzed the transcriptomes of PBMCs from the peripheral blood of 5 kidney transplant patients taken at the time of indicated biopsy. We filtered these data to focus on monocytes and compared these data with previously published monocytes/macrophage transcriptomes from paired biopsies.
Project description:Gain-of-function mutations in STING1, that codes for the Stimulator of Interferon Gene (STING), result in a severe autoinflammatory disease termed STING-associated vasculopathy with onset in infancy (SAVI). Although elevated type I interferon (IFN) production is thought to be the leading cause of the symptoms observed in patients, STING can induce a set of pathways, and their role in the onset and severity of SAVI remains to be elucidated. To address this point, we compared a single-cell RNA sequencing (scRNA-seq) dataset of peripheral blood mononuclear cells (PBMCs) from SAVI patients to a dataset of healthy PBMCs treated with recombinant IFN-β. We revealed a loss of mucosal associated invariant T cells and CD56bright natural killer cells in SAVI patients, not replicated in IFN-β-treated PBMC. Patient T cells are in an activated state associated with senescence and apoptosis, dependent on type I IFNs. Inferring cell to cell communication, from scRNA-seq predicted monocytes as potential drivers of this T cell phenotype and was supported by plasma cytokines measurement, with high CCL3, CCL4 and IL-6. Furthermore, scRNA-seq clustering identified a patient-specific subset of monocytes, highly inflammatory and expressing a strong integrated stress response (ISR). It also pinpointed to a patient with lower ISR, allowing us to identify a secondary mutation in PERK, that was recently shown to be activated by STING to trigger the ISR. Finally, based on the identification of this patient-specific subset of monocytes and the exploration of IFN-β stimulated PBMCs from healthy donors, we developed a strategy to propose a transcriptomic signature specific of STING activation and independent of type I IFN. Altogether, these results provide a deeper understanding of SAVI at the cellular and molecular levels.
Project description:Gain-of-function mutations in STING1, that codes for the Stimulator of Interferon Gene (STING), result in a severe autoinflammatory disease termed STING-associated vasculopathy with onset in infancy (SAVI). Although elevated type I interferon (IFN) production is thought to be the leading cause of the symptoms observed in patients, STING can induce a set of pathways, and their role in the onset and severity of SAVI remains to be elucidated. To address this point, we compared a single-cell RNA sequencing (scRNA-seq) dataset of peripheral blood mononuclear cells (PBMCs) from SAVI patients to a dataset of healthy PBMCs treated with recombinant IFN-β. We revealed a loss of mucosal associated invariant T cells and CD56bright natural killer cells in SAVI patients, not replicated in IFN-β-treated PBMC. Patient T cells are in an activated state associated with senescence and apoptosis, dependent on type I IFNs. Inferring cell to cell communication, from scRNA-seq predicted monocytes as potential drivers of this T cell phenotype and was supported by plasma cytokines measurement, with high CCL3, CCL4 and IL-6. Furthermore, scRNA-seq clustering identified a patient-specific subset of monocytes, highly inflammatory and expressing a strong integrated stress response (ISR). It also pinpointed to a patient with lower ISR, allowing us to identify a secondary mutation in PERK, that was recently shown to be activated by STING to trigger the ISR. Finally, based on the identification of this patient-specific subset of monocytes and the exploration of IFN-β stimulated PBMCs from healthy donors, we developed a strategy to propose a transcriptomic signature specific of STING activation and independent of type I IFN. Altogether, these results provide a deeper understanding of SAVI at the cellular and molecular levels.