Project description:Aged hematopoietic stem cells (HSCs) display myeloid-biased differentiation and reduced regenerative potential. In this study, we uncover that P-selectin (Selp) marks a subset of aged HSCs with reduced repopulation capacity. This population of HSCs expresses a prominent aging transcriptome. Overexpression of Selp in young HSCs impaired long-term reconstitution potential and repressed erythropoiesis. We show that IL-1β is elevated in aged bone marrow and administration of IL-1β induces expression of Selp and other aging-associated genes in HSCs. Finally, we demonstrate that transplantation of aged HSCs into young recipients restores a young-like transcriptome, specifically by repressing pro-inflammatory pathways, highlighting the important role of the bone marrow microenvironment in HSC aging.
Project description:The importance of unanchored Ub in innate immunity has been shown only for a limited number of unanchored Ub-interactors. We investigated what additional cellular factors interact with unanchored Ub and whether unanchored Ub plays a broader role in innate immunity. To identify unanchored Ub-interacting factors from murine lungs, we used His-tagged recombinant poly-Ub chains as bait. These chains were mixed with lung tissue lysates and protein complexes were isolated with Ni-NTA beads. Sample elutions were subjected to mass spectrometry (LC-MSMS) analysis.
Project description:In mammals, retinal damage is followed by Müller glia cell activation and proliferation. While retinal gliosis persists in adult mammals after an insult or disease, some vertebrates, including zebrafish, have the capacity to regenerate. We believe we are the first group to show that gliosis is a fibrotic-like process in mammals’ eyes caused by differential activation of canonical and non-canonical TGFβ signaling pathways.
Project description:Interleukin-1 (IL-1) is a key pro-inflammatory cytokine, which has diverse actions in the brain as a regulator of host defence responses and a mediator of inflammation. Two major agonists, IL-1α and IL-1β bind to a single known functional (type-1) IL-1 receptor (IL-1RI), which associates with an accessory protein (IL-1RAcP) leading to signal transduction. However, recent evidence suggests that some actions of IL-1 in the brain may be independent of IL-1R1 and its classical signalling pathways, pointing to an as yet unidentified functional receptor for IL-1 expressed in the CNS. In this study, cDNA array based gene expression profiling was used to identify possible genes induced by IL-1β independently of IL-1R1. The results show that IL-1β may indeed regulate some genes independently of IL-1R1, suggesting the presence of additional functional IL-1 receptors in the mouse brain. Keywords: experimental treatment (IL-1β), gene ablation (IL-1R1), glia
