TY - JOUR A1 - Bell, Luisa A1 - Lenhart, Alexander A1 - Rosenwald, Andreas A1 - Monoranu, Camelia M. A1 - Berberich-Siebelt, Friederike T1 - Lymphoid aggregates in the CNS of progressive multiple sclerosis patients lack regulatory T cells JF - Frontiers in Immunology N2 - In gray matter pathology of multiple sclerosis, neurodegeneration associates with a high degree of meningeal inflammatory activity. Importantly, ectopic lymphoid follicles (eLFs) were identified at the inflamed meninges of patients with progressive multiple sclerosis. Besides T lymphocytes, they comprise B cells and might elicit germinal center (GC)-like reactions. GC reactions are controlled by FOXP3+ T-follicular regulatory cells (TFR), but it is unknown if they participate in autoantibody production in eLFs. Receiving human post-mortem material, gathered from autopsies of progressive multiple sclerosis patients, indeed, distinct inflammatory infiltrates enriched with B cells could be detected in perivascular areas and deep sulci. CD35+ cells, parafollicular CD138+ plasma cells, and abundant expression of the homing receptor for GCs, CXCR5, on lymphocytes defined some of them as eLFs. However, they resembled GCs only in varying extent, as T cells did not express PD-1, only few cells were positive for the key transcriptional regulator BCL-6 and ongoing proliferation, whereas a substantial number of T cells expressed high NFATc1 like GC-follicular T cells. Then again, predominant cytoplasmic NFATc1 and an enrichment with CD3+CD27+ memory and CD4+CD69+ tissue-resident cells implied a chronic state, very much in line with PD-1 and BCL-6 downregulation. Intriguingly, FOXP3+ cells were almost absent in the whole brain sections and CD3+FOXP3+ TFRs were never found in the lymphoid aggregates. This also points to less controlled humoral immune responses in those lymphoid aggregates possibly enabling the occurrence of CNS-specific autoantibodies in multiple sclerosis patients. KW - ectopic lymphoid follicle KW - lymphoid aggregate KW - T-follicular regulatory cell KW - meningeal inflammation KW - NFATc1 KW - progressive multiple sclerosis Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-198130 SN - 1664-3224 VL - 10 IS - 3090 ER - TY - JOUR A1 - Majumder, Snigdha A1 - Jugovic, Isabelle A1 - Saul, Domenica A1 - Bell, Luisa A1 - Hundhausen, Nadine A1 - Seal, Rishav A1 - Beilhack, Andreas A1 - Rosenwald, Andreas A1 - Mougiakakos, Dimitrios A1 - Berberich-Siebelt, Friederike T1 - Rapid and Efficient Gene Editing for Direct Transplantation of Naive Murine Cas9\(^+\) T Cells JF - Frontiers in Immunology N2 - Gene editing of primary T cells is a difficult task. However, it is important for research and especially for clinical T-cell transfers. CRISPR/Cas9 is the most powerful gene-editing technique. It has to be applied to cells by either retroviral transduction or electroporation of ribonucleoprotein complexes. Only the latter is possible with resting T cells. Here, we make use of Cas9 transgenic mice and demonstrate nucleofection of pre-stimulated and, importantly, of naive CD3\(^+\) T cells with guideRNA only. This proved to be rapid and efficient with no need of further selection. In the mixture of Cas9\(^+\)CD3\(^+\) T cells, CD4\(^+\) and CD8\(^+\) conventional as well as regulatory T cells were targeted concurrently. IL-7 supported survival and naivety in vitro, but T cells were also transplantable immediately after nucleofection and elicited their function like unprocessed T cells. Accordingly, metabolic reprogramming reached normal levels within days. In a major mismatch model of GvHD, not only ablation of NFATc1 and/or NFATc2, but also of the NFAT-target gene IRF4 in naïve primary murine Cas9\(^+\)CD3\(^+\) T cells by gRNA-only nucleofection ameliorated GvHD. However, pre-activated murine T cells could not achieve long-term protection from GvHD upon single NFATc1 or NFATc2 knockout. This emphasizes the necessity of gene-editing and transferring unstimulated human T cells during allogenic hematopoietic stem cell transplantation. KW - CRISPR/Cas9 KW - gRNA-only KW - GvHD KW - metabolism KW - NFAT KW - naive T-cell gene editing KW - T-cell transfer KW - IRF4 Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-242896 SN - 1664-3224 VL - 12 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 -