Project description:To determine whether dural fibroblasts (DuF) under IL-1β-mediated wound conditions, release pro-angiogenic factors, and promote angiogenic properties in human endothelial cells (ECs). DuF were stimulated by pro-inflammatory cytokines interleukin (IL)-1β, and transcriptome sequencing was then used to identify the differentially expressed genes in the DuF with/without IL-1β stimulation (DuFCon/DuFIL1b)
Project description:To investigate cellular landscape of dural immune cells, dural immune cells from 30 P28 male mice and 30 P7 male mice were FACS sorted and single-cell RNA seqs were performed
Project description:The aim of our study was to determin if papillary and reticular fibroblasts cell sheets expressed distinct genes involved in angiogenesis regulation and extracellular matrix. Thanks to our RNAseq analyssis, we demonstrated that papillary and reticular fibroblasts express specific signature of genes related to secreted angiogenic regulators and matrisome genes, suggesting that each subtype of fibroblasts differently regulate the formation of capillary via secreted factors and the microenvironment they generate. We confirmed this hypothesis with functional angiogenesis model in vitro. Overall, we show that papillary fibroblasts have a greater angiogenic potential and support the formation of dense branched vascular netword. On the other hand, reticular fibroblasts allow the formation of fewer vessel of larger diameter. This resultats are coherent with native skin vasculature and suggest that each fibroblasts subtypes play a role in regulating skin vascularisation.
Project description:Each organ of the human body requires locally-adapted blood vessels1–3. The gain of such organotypic vessel specializations is often deemed molecularly unrelated to the process of organ vascularization. Opposing this model, we reveal a molecular mechanism for brain-specific angiogenesis that operates under the control of Wnt7a/b ligands, well-known blood-brain barrier maturation signals4–6. The control mechanism relies on Wnt7a/b-dependent expression of Mmp25 in brain endothelial cells. This hitherto poorly characterized GPI-anchored matrix metalloproteinase is selectively required in endothelial tip cells to enable their initial migration across the pial basement membrane which lines the brain surface, and whose distinctive molecular composition is controlled by embryonic pial fibroblasts. Mechanistically, Mmp25 confers brain invasive competence by cleaving the pial basement membrane-enriched Col4a5/6 within a short non-collagenous region of the central helical part of the heterotrimer. Upon genetic interference with pial basement membrane composition, the Wnt/β-catenin-dependent organotypic control of brain angiogenesis is lost, resulting in a properly patterned, yet blood-brain barrier-defective cerebrovasculature. This work reveals an organ-specific angiogenesis mechanism, sheds light on tip cell mechanistic angiodiversity, and thereby illustrates how organs, by imposing local constraints on angiogenic tip cells, can select vessels matching their distinctive physiological requirements.
Project description:To investigate different responses of dural macrophage subsets to systemic viral infection, we collected the dura mater from mice 12 h after systemic LCMV infection and macrophages were sorted
Project description:We tested the hypothesis that endothelial capillary tube formation in 3D cultures in basement membrane extract (BME) is secondary to the altered DNA promoter methylation and mRNA expression in Human Brain Micro Endothelial Cells (HBMEC). We conducted a whole-genome transcriptomic and methylation microarray and CRISPR/Cas9-mediated gene knockdown to test our hypothesis. The data demonstrated that with angiogenic transformation 1318 and 1490 genes were significantly (p<0.05) upregulated and downregulated, respectively. We compared our gene expression data with the published databases on GEO and found several genes in common. PTGS2, SELE, ID2, HSPA6, DLX2, HEY2, FOSB, SMAD6, SMAD7, and SMAD9 showed a very high level of expression during capillary tube formation. Among downregulated gene were ITGB4, TNNT1, PRSS35, TXNIP, IGFBP5. The most affected canonical pathways were ATM signaling and cell cycle G2/M DNA damage checkpoint regulation. The top upstream regulators of angiogenic transformation were identified to be VEGF, TP53, HGF, ESR1, and CDKN1A. We compared the changes in gene expression with the change in gene methylation and found hypomethylation of the CpG sites was associated with upregulation of 515 genes and hypermethylation was associated with the downregulation of 31 genes. Furthermore, the silencing of FOSB, FZD7, HEY2, HSPA6, NR4A3, SELE, PTGS2, SMAD6, SMAD7, and SMAD9 significantly inhibited angiogenic transformation as well as cell migration of HBMECs. We conclude that the angiogenic transformation is associated with altered DNA methylation and gene expression changes.