TY - JOUR A1 - Kleefeldt, Florian A1 - Bömmel, Heike A1 - Broede, Britta A1 - Thomsen, Michael A1 - Pfeiffer, Verena A1 - Wörsdörfer, Philipp A1 - Karnati, Srikanth A1 - Wagner, Nicole A1 - Rueckschloss, Uwe A1 - Ergün, Süleyman T1 - Aging‐related carcinoembryonic antigen‐related cell adhesion molecule 1 signaling promotes vascular dysfunction JF - Aging Cell N2 - Aging is an independent risk factor for cardiovascular diseases and therefore of particular interest for the prevention of cardiovascular events. However, the mechanisms underlying vascular aging are not well understood. Since carcinoembryonic antigen‐related cell adhesion molecule 1 (CEACAM1) is crucially involved in vascular homeostasis, we sought to identify the role of CEACAM1 in vascular aging. Using human internal thoracic artery and murine aorta, we show that CEACAM1 is upregulated in the course of vascular aging. Further analyses demonstrated that TNF‐α is CEACAM1‐dependently upregulated in the aging vasculature. Vice versa, TNF‐α induces CEACAM1 expression. This results in a feed‐forward loop in the aging vasculature that maintains a chronic pro‐inflammatory milieu. Furthermore, we demonstrate that age‐associated vascular alterations, that is, increased oxidative stress and vascular fibrosis, due to increased medial collagen deposition crucially depend on the presence of CEACAM1. Additionally, age‐dependent upregulation of vascular CEACAM1 expression contributes to endothelial barrier impairment, putatively via increased VEGF/VEGFR‐2 signaling. Consequently, aging‐related upregulation of vascular CEACAM1 expression results in endothelial dysfunction that may promote atherosclerotic plaque formation in the presence of additional risk factors. Our data suggest that CEACAM1 might represent an attractive target in order to delay physiological aging and therefore the transition to vascular disorders such as atherosclerosis. KW - aging KW - anti‐aging KW - cytokines KW - inflammation KW - mouse KW - reactive oxygen species Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-201231 VL - 2019 IS - 18 ER - TY - JOUR A1 - Koeniger, Tobias A1 - Bell, Luisa A1 - Mifka, Anika A1 - Enders, Michael A1 - Hautmann, Valentin A1 - Mekala, Subba Rao A1 - Kirchner, Philipp A1 - Ekici, Arif B. A1 - Schulz, Christian A1 - Wörsdörfer, Philipp A1 - Mencl, Stine A1 - Kleinschnitz, Christoph A1 - Ergün, Süleyman A1 - Kuerten, Stefanie T1 - Bone marrow‐derived myeloid progenitors in the leptomeninges of adult mice JF - Stem Cells N2 - Although the bone marrow contains most hematopoietic activity during adulthood, hematopoietic stem and progenitor cells can be recovered from various extramedullary sites. Cells with hematopoietic progenitor properties have even been reported in the adult brain under steady‐state conditions, but their nature and localization remain insufficiently defined. Here, we describe a heterogeneous population of myeloid progenitors in the leptomeninges of adult C57BL/6 mice. This cell pool included common myeloid, granulocyte/macrophage, and megakaryocyte/erythrocyte progenitors. Accordingly, it gave rise to all major myelo‐erythroid lineages in clonogenic culture assays. Brain‐associated progenitors persisted after tissue perfusion and were partially inaccessible to intravenous antibodies, suggesting their localization behind continuous blood vessel endothelium such as the blood‐arachnoid barrier. Flt3\(^{Cre}\) lineage tracing and bone marrow transplantation showed that the precursors were derived from adult hematopoietic stem cells and were most likely continuously replaced via cell trafficking. Importantly, their occurrence was tied to the immunologic state of the central nervous system (CNS) and was diminished in the context of neuroinflammation and ischemic stroke. Our findings confirm the presence of myeloid progenitors at the meningeal border of the brain and lay the foundation to unravel their possible functions in CNS surveillance and local immune cell production. KW - hematopoietic KW - meninges KW - mouse KW - myeloid KW - progenitor Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-224452 VL - 39 IS - 2 SP - 227 EP - 239 ER -