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Mumme H, Thomas BE, Bhasin SS, Krishnan U, Dwivedi B, Perumalla P, Sarkar D, Ulukaya GB, Sabnis HS, Park SI, DeRyckere D, Raikar SS, Pauly M, Summers RJ, Castellino SM, Wechsler DS, Porter CC, Graham DK, Bhasin M. Single-cell analysis reveals altered tumor microenvironments of relapse- and remission-associated pediatric acute myeloid leukemia. Nat Commun 2023; 14:6209. [PMID: 37798266 PMCID: PMC10556066 DOI: 10.1038/s41467-023-41994-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Accepted: 09/25/2023] [Indexed: 10/07/2023] Open
Abstract
Acute myeloid leukemia (AML) microenvironment exhibits cellular and molecular differences among various subtypes. Here, we utilize single-cell RNA sequencing (scRNA-seq) to analyze pediatric AML bone marrow (BM) samples from diagnosis (Dx), end of induction (EOI), and relapse timepoints. Analysis of Dx, EOI scRNA-seq, and TARGET AML RNA-seq datasets reveals an AML blasts-associated 7-gene signature (CLEC11A, PRAME, AZU1, NREP, ARMH1, C1QBP, TRH), which we validate on independent datasets. The analysis reveals distinct clusters of Dx relapse- and continuous complete remission (CCR)-associated AML-blasts with differential expression of genes associated with survival. At Dx, relapse-associated samples have more exhausted T cells while CCR-associated samples have more inflammatory M1 macrophages. Post-therapy EOI residual blasts overexpress fatty acid oxidation, tumor growth, and stemness genes. Also, a post-therapy T-cell cluster associated with relapse samples exhibits downregulation of MHC Class I and T-cell regulatory genes. Altogether, this study deeply characterizes pediatric AML relapse- and CCR-associated samples to provide insights into the BM microenvironment landscape.
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Affiliation(s)
- Hope Mumme
- Department of Biomedical Informatics, Emory University School of Medicine, Atlanta, GA, USA
| | - Beena E Thomas
- Aflac Cancer and Blood Disorders Center, Children's Healthcare of Atlanta, Atlanta, GA, USA
- Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, USA
| | - Swati S Bhasin
- Aflac Cancer and Blood Disorders Center, Children's Healthcare of Atlanta, Atlanta, GA, USA
- Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, USA
| | - Upaasana Krishnan
- Department of Biomedical Informatics, Emory University School of Medicine, Atlanta, GA, USA
- Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA, USA
| | - Bhakti Dwivedi
- Department of Biostatistics and Bioinformatics Shared Resource, Winship Cancer Institute, Emory University, Atlanta, GA, USA
| | - Pruthvi Perumalla
- Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA, USA
| | - Debasree Sarkar
- Department of Biomedical Informatics, Emory University School of Medicine, Atlanta, GA, USA
- Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, USA
| | - Gulay B Ulukaya
- Department of Biomedical Informatics, Emory University School of Medicine, Atlanta, GA, USA
| | - Himalee S Sabnis
- Aflac Cancer and Blood Disorders Center, Children's Healthcare of Atlanta, Atlanta, GA, USA
- Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, USA
| | - Sunita I Park
- Department of Pathology, Children's Healthcare of Atlanta, Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, GA, USA
| | - Deborah DeRyckere
- Aflac Cancer and Blood Disorders Center, Children's Healthcare of Atlanta, Atlanta, GA, USA
- Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, USA
| | - Sunil S Raikar
- Aflac Cancer and Blood Disorders Center, Children's Healthcare of Atlanta, Atlanta, GA, USA
- Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, USA
| | - Melinda Pauly
- Aflac Cancer and Blood Disorders Center, Children's Healthcare of Atlanta, Atlanta, GA, USA
- Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, USA
| | - Ryan J Summers
- Aflac Cancer and Blood Disorders Center, Children's Healthcare of Atlanta, Atlanta, GA, USA
- Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, USA
| | - Sharon M Castellino
- Aflac Cancer and Blood Disorders Center, Children's Healthcare of Atlanta, Atlanta, GA, USA
- Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, USA
| | - Daniel S Wechsler
- Aflac Cancer and Blood Disorders Center, Children's Healthcare of Atlanta, Atlanta, GA, USA
- Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, USA
| | - Christopher C Porter
- Aflac Cancer and Blood Disorders Center, Children's Healthcare of Atlanta, Atlanta, GA, USA
- Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, USA
| | - Douglas K Graham
- Aflac Cancer and Blood Disorders Center, Children's Healthcare of Atlanta, Atlanta, GA, USA
- Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, USA
| | - Manoj Bhasin
- Department of Biomedical Informatics, Emory University School of Medicine, Atlanta, GA, USA.
- Aflac Cancer and Blood Disorders Center, Children's Healthcare of Atlanta, Atlanta, GA, USA.
- Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, USA.
- Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA, USA.
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2
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Elchaninov A, Vishnyakova P, Lokhonina A, Kiseleva V, Menyailo E, Antonova M, Mamedov A, Arutyunyan I, Bolshakova G, Goldshtein D, Bao X, Fatkhudinov T, Sukhikh G. Spleen regeneration after subcutaneous heterotopic autotransplantation in a mouse model. Biol Res 2023; 56:15. [PMID: 36991509 DOI: 10.1186/s40659-023-00427-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Accepted: 03/20/2023] [Indexed: 03/31/2023] Open
Abstract
BACKGROUND Splenectomy may lead to severe postoperative complications, including sepsis and cancers. A possible solution to this problem is heterotopic autotransplantation of the spleen. Splenic autografts rapidly restore the regular splenic microanatomy in model animals. However, the functional competence of such regenerated autografts in terms of lympho- and hematopoietic capacity remains uncertain. Therefore, this study aimed to monitor the dynamics of B and T lymphocyte populations, the monocyte-macrophage system, and megakaryocytopoiesis in murine splenic autografts. METHODS The model of subcutaneous splenic engraftment was implemented in C57Bl male mice. Cell sources of functional recovery were studied using heterotopic transplantations from B10-GFP donors to C57Bl recipients. The cellular composition dynamics were studied by immunohistochemistry and flow cytometry. Expression of regulatory genes at mRNA and protein levels was assessed by real-time PCR and Western blot, respectively. RESULTS Characteristic splenic architecture is restored within 30 days post-transplantation, consistent with other studies. The monocyte-macrophage system, megakaryocytes, and B lymphocytes show the highest rates, whereas the functional recovery of T cells takes longer. Cross-strain splenic engraftments using B10-GFP donors indicate the recipient-derived cell sources of the recovery. Transplantations of scaffolds populated with splenic stromal cells or without them afforded no restoration of the characteristic splenic architecture. CONCLUSIONS Allogeneic subcutaneous transplantation of splenic fragments in a mouse model leads to their structural recovery within 30 days, with full reconstitution of the monocyte-macrophage, megakaryocyte and B lymphocyte populations. The circulating hematopoietic cells provide the likely source for the cell composition recovery.
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Affiliation(s)
- Andrey Elchaninov
- Laboratory of Growth and Development, Avtsyn Research Institute of Human Morphology of FSBI Petrovsky National Research Centre of Surgery, Moscow, Russia.
- Histology Department, Medical Institute, Peoples' Friendship University of Russia (RUDN University), Moscow, Russia.
| | - Polina Vishnyakova
- Laboratory of Regenerative Medicine, National Medical Research Center for Obstetrics, Gynecology and Perinatology Named after Academician V.I. Kulakov of Ministry of Healthcare of Russian Federation, Moscow, Russia
- Histology Department, Medical Institute, Peoples' Friendship University of Russia (RUDN University), Moscow, Russia
| | - Anastasiya Lokhonina
- Laboratory of Regenerative Medicine, National Medical Research Center for Obstetrics, Gynecology and Perinatology Named after Academician V.I. Kulakov of Ministry of Healthcare of Russian Federation, Moscow, Russia
- Histology Department, Medical Institute, Peoples' Friendship University of Russia (RUDN University), Moscow, Russia
| | - Viktoria Kiseleva
- Laboratory of Regenerative Medicine, National Medical Research Center for Obstetrics, Gynecology and Perinatology Named after Academician V.I. Kulakov of Ministry of Healthcare of Russian Federation, Moscow, Russia
| | - Egor Menyailo
- Laboratory of Growth and Development, Avtsyn Research Institute of Human Morphology of FSBI Petrovsky National Research Centre of Surgery, Moscow, Russia
| | - Maria Antonova
- Histology Department, Pirogov Russian National Research Medical University, Ministry of Healthcare of the Russian Federation, Moscow, Russia
| | - Aiaz Mamedov
- Histology Department, Pirogov Russian National Research Medical University, Ministry of Healthcare of the Russian Federation, Moscow, Russia
| | - Irina Arutyunyan
- Laboratory of Regenerative Medicine, National Medical Research Center for Obstetrics, Gynecology and Perinatology Named after Academician V.I. Kulakov of Ministry of Healthcare of Russian Federation, Moscow, Russia
| | - Galina Bolshakova
- Laboratory of Growth and Development, Avtsyn Research Institute of Human Morphology of FSBI Petrovsky National Research Centre of Surgery, Moscow, Russia
| | - Dmitry Goldshtein
- Laboratory of Stem Cells Genetics, Research Center of Medical Genetics, Moscow, Russia
| | - Xuhui Bao
- Institute of Therapeutic Cancer Vaccines, Fudan University Pudong Medical Center, Shanghai, China
| | - Timur Fatkhudinov
- Laboratory of Growth and Development, Avtsyn Research Institute of Human Morphology of FSBI Petrovsky National Research Centre of Surgery, Moscow, Russia
- Histology Department, Medical Institute, Peoples' Friendship University of Russia (RUDN University), Moscow, Russia
| | - Gennady Sukhikh
- Laboratory of Regenerative Medicine, National Medical Research Center for Obstetrics, Gynecology and Perinatology Named after Academician V.I. Kulakov of Ministry of Healthcare of Russian Federation, Moscow, Russia
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3
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Extramedullary hematopoiesis: mesenchymal stromal cells from spleen provide an in vitro niche for myelopoiesis. In Vitro Cell Dev Biol Anim 2022; 58:429-439. [PMID: 35641778 PMCID: PMC9213314 DOI: 10.1007/s11626-022-00693-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2022] [Accepted: 05/09/2022] [Indexed: 11/05/2022]
Abstract
Murine spleen has been shown to harbour stromal cells that support hematopoiesis with production of myeloid antigen-presenting cells. Similar stromal lines have now been isolated from long-term cultures (LTC) of human spleen. When human progenitor populations from spleen, bone marrow and cord blood were employed as a source of progenitors for co-culture above splenic stromal lines, myelopoiesis was supported. Human splenocytes gave production of predominantly myeloid dendritic-like cells, with minor subsets resembling conventional dendritic cells (cDC) cells, and myeloid or monocyte-derived DC. Human bone marrow progenitors gave rise to myelopoiesis from hematopoietic progenitors, while human cord blood supported limited myelopoiesis from existing myeloid precursors. Transcriptome analysis compared two stromal lines differing in myelopoietic support capacity. Gene profiling revealed both stromal lines to reflect perivascular reticular cells with osteogenic characteristics. However, the 5C6 stroma which failed to support hematopoiesis uniquely expressed several inhibitors of the WNT pathway. Combined data now show that splenic stroma of both human and murine origin provides a mesenchymal stromal cell microenvironment which is WNT pathway-dependent, and which supports in vitro myelopoiesis with production of specific subsets of myeloid and dendritic-like cells.
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Tran V, O’Neill HC. Role of SVEP1 in Stroma-Dependent Hematopoiesis In vitro. Front Cell Dev Biol 2022; 9:760480. [PMID: 35174156 PMCID: PMC8841349 DOI: 10.3389/fcell.2021.760480] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Accepted: 12/28/2021] [Indexed: 11/13/2022] Open
Abstract
Study of the microenvironment that supports hematopoietic stem cell (HSC) development in vivo is very difficult involving small numbers of interacting cells which are usually not well defined. While much is known about HSC niches located within the bone marrow in terms of contributing cell types and signalling molecules, very little is known about equivalent niches within spleen. Extramedullary hematopoiesis in spleen contributes myeloid cells important in the mobilisation of an immune response. As a result, it is important to develop in vitro models to identify the cells which constitute HSC niches in spleen and to identify the regulatory molecules supporting myeloid cell development. Studies described here document a model system to study the maintenance and differentiation of HSC by splenic stromal cells in vitro. The splenic stromal lines 5G3 and 3B5 differ in hematopoietic support capacity. SVEP1 and IGF2 are molecules of interest specifically expressed by 5G3 stroma. Gene knockdown technology using shRNA plasmids has been used to reduce gene expression in 5G3 and to determine specific effects on myeloid cell development following co-culture with overlaid hematopoietic progenitors in vitro. Knockdown of Svep1 gave specific inhibition of a dendritic cell (DC) population described previously in spleen (L-DC). Knockdown of Igf2 resulted in loss of production of a minor subset of conventional (c) DC. SVEP1 is now considered a marker of mesenchymal stromal cells with osteogenic differentiative capacity reflective of perivascular stromal cells. The power of this in vitro model is evidenced by the fact that it has been used to define SVEP1 as a specific adhesion molecule that regulates the hematopoietic process dependent on stromal niche interaction. The identification of stromal cells and molecules that contribute to the hematopoietic process in spleen, brings us closer to the realm of therapeutically regulating hematopoiesis in vivo, and to inhibiting niches which support cancer stem cells.
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Affiliation(s)
- Vinson Tran
- Research School of Biology, Australian National University, Canberra, ACT, Australia
| | - Helen C. O’Neill
- Clem Jones Centre for Regenerative Medicine, Bond University, Gold Coast, QLD, Australia
- *Correspondence: Helen C. O’Neill,
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5
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Correa-Gallegos D, Jiang D, Rinkevich Y. Fibroblasts as confederates of the immune system. Immunol Rev 2021; 302:147-162. [PMID: 34036608 DOI: 10.1111/imr.12972] [Citation(s) in RCA: 55] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Revised: 04/28/2021] [Accepted: 04/28/2021] [Indexed: 12/18/2022]
Abstract
Fibroblastic stromal cells are as diverse, in origin and function, as the niches they fashion in the mammalian body. This cellular variety impacts the spectrum of responses elicited by the immune system. Fibroblast influence on the immune system keeps evolving our perspective on fibroblast roles and functions beyond just a passive structural part of organs. This review discusses the foundations of fibroblastic stromal-immune crosstalk, under the scope of stromal heterogeneity as a basis for tissue-specific tutoring of the immune system. Focusing on the skin as a relevant immunological organ, we detail the complex interactions between distinct fibroblast populations and immune cells that occur during homeostasis, injury repair, scarring, and disease. We further review the relevance of fibroblastic stromal cell heterogeneity and how this heterogeneity is central to regulate the immune system from its inception during embryonic development into adulthood.
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Affiliation(s)
- Donovan Correa-Gallegos
- Institute of Lung Biology and Disease, Comprehensive Pneumology Center, Helmholtz Zentrum München, Munich, Germany
| | - Dongsheng Jiang
- Institute of Lung Biology and Disease, Comprehensive Pneumology Center, Helmholtz Zentrum München, Munich, Germany
| | - Yuval Rinkevich
- Institute of Regenerative Biology and Medicine, Helmholtz Zentrum München, Munich, Germany
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6
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Cismaru AL, Rudin D, Ibañez L, Liakoni E, Bonadies N, Kreutz R, Carvajal A, Lucena MI, Martin J, Sancho Ponce E, Molokhia M, Eriksson N, Krähenbühl S, Largiadèr CR, Haschke M, Hallberg P, Wadelius M, Amstutz U. Genome-Wide Association Study of Metamizole-Induced Agranulocytosis in European Populations. Genes (Basel) 2020; 11:genes11111275. [PMID: 33138277 PMCID: PMC7716224 DOI: 10.3390/genes11111275] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2020] [Revised: 10/23/2020] [Accepted: 10/27/2020] [Indexed: 12/17/2022] Open
Abstract
Agranulocytosis is a rare yet severe idiosyncratic adverse drug reaction to metamizole, an analgesic widely used in countries such as Switzerland and Germany. Notably, an underlying mechanism has not yet been fully elucidated and no predictive factors are known to identify at-risk patients. With the aim to identify genetic susceptibility variants to metamizole-induced agranulocytosis (MIA) and neutropenia (MIN), we conducted a retrospective multi-center collaboration including cases and controls from three European populations. Association analyses were performed using genome-wide genotyping data from a Swiss cohort (45 cases, 191 controls) followed by replication in two independent European cohorts (41 cases, 273 controls) and a joint discovery meta-analysis. No genome-wide significant associations (p < 1 × 10−7) were observed in the Swiss cohort or in the joint meta-analysis, and no candidate genes suggesting an immune-mediated mechanism were identified. In the joint meta-analysis of MIA cases across all cohorts, two candidate loci on chromosome 9 were identified, rs55898176 (OR = 4.01, 95%CI: 2.41–6.68, p = 1.01 × 10−7) and rs4427239 (OR = 5.47, 95%CI: 2.81–10.65, p = 5.75 × 10−7), of which the latter is located in the SVEP1 gene previously implicated in hematopoiesis. This first genome-wide association study for MIA identified suggestive associations with biological plausibility that may be used as a stepping-stone for post-GWAS analyses to gain further insight into the mechanism underlying MIA.
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Affiliation(s)
- Anca Liliana Cismaru
- Department of Clinical Chemistry, Inselspital Bern University Hospital, University of Bern, 3010 Bern, Switzerland; (A.L.C.); (C.R.L.)
- Graduate School for Cellular and Biomedical Sciences, University of Bern, 3012 Bern, Switzerland
| | - Deborah Rudin
- Department of Clinical Pharmacology & Toxicology, University Hospital Basel, University of Basel, 4031 Basel, Switzerland; (D.R.); (S.K.)
- Department of Biomedicine, University of Basel, 4051 Basel, Switzerland
| | - Luisa Ibañez
- Clinical Pharmacology Service, Hospital Universitari Vall d’Hebron, Department of Pharmacology, Therapeutics and Toxicology, Autonomous University of Barcelona, Fundació Institut Català de Farmacología, 08035 Barcelona, Spain;
| | - Evangelia Liakoni
- Department of Clinical Pharmacology & Toxicology, Inselspital Bern University Hospital, University of Bern, 3010 Bern, Switzerland; (E.L.); (M.H.)
- Institute of Pharmacology, University of Bern, 3012 Bern, Switzerland
| | - Nicolas Bonadies
- Department of Hematology and Central Hematology Laboratory, Inselspital Bern University Hospital, University of Bern, 3010 Bern, Switzerland;
| | - Reinhold Kreutz
- Charité–Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Institut für Klinische Pharmakologie und Toxikologie, 10117 Berlin, Germany;
| | - Alfonso Carvajal
- Centro de Estudios sobre la Seguridad de los Medicamentos, Universidad de Valladolid, 47005 Valladolid, Spain;
| | - Maria Isabel Lucena
- Servicio Farmacologia Clinica, Instituto de Investigación Biomedica de Málaga, Hospital Universitario Virgen de la Victoria, Universidad de Málaga, 29010 Málaga, Spain;
| | - Javier Martin
- Instituto de Parasitología y Biomedicina Lopez-Neyra, Consejo Superior de Investigaciones Cientiíficas, 18016 Granada, Spain;
| | - Esther Sancho Ponce
- Servei d’Hematologia i Banc de Sang, Hospital General de Catalunya, 08190 Sant Cugat del Vallès, Spain;
| | - Mariam Molokhia
- Department of Population Health Sciences, King’s College London, London WC2R 2LS, UK;
| | - Niclas Eriksson
- Uppsala Clinical Research Center and Department of Medical Sciences, Uppsala University, 751 85 Uppsala, Sweden;
| | | | - Stephan Krähenbühl
- Department of Clinical Pharmacology & Toxicology, University Hospital Basel, University of Basel, 4031 Basel, Switzerland; (D.R.); (S.K.)
| | - Carlo R. Largiadèr
- Department of Clinical Chemistry, Inselspital Bern University Hospital, University of Bern, 3010 Bern, Switzerland; (A.L.C.); (C.R.L.)
| | - Manuel Haschke
- Department of Clinical Pharmacology & Toxicology, Inselspital Bern University Hospital, University of Bern, 3010 Bern, Switzerland; (E.L.); (M.H.)
- Institute of Pharmacology, University of Bern, 3012 Bern, Switzerland
| | - Pär Hallberg
- Department of Medical Sciences, Clinical Pharmacology and Science for Life Laboratory, Uppsala University, 751 85 Uppsala, Sweden; (P.H.); (M.W.)
| | - Mia Wadelius
- Department of Medical Sciences, Clinical Pharmacology and Science for Life Laboratory, Uppsala University, 751 85 Uppsala, Sweden; (P.H.); (M.W.)
| | - Ursula Amstutz
- Department of Clinical Chemistry, Inselspital Bern University Hospital, University of Bern, 3010 Bern, Switzerland; (A.L.C.); (C.R.L.)
- Correspondence:
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7
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Short C, Lim HK, Tan J, O'Neill HC. Targeting the Spleen as an Alternative Site for Hematopoiesis. Bioessays 2019; 41:e1800234. [PMID: 30970171 DOI: 10.1002/bies.201800234] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2018] [Revised: 02/25/2019] [Indexed: 12/21/2022]
Abstract
Bone marrow is the main site for hematopoiesis in adults. It acts as a niche for hematopoietic stem cells (HSCs) and contains non-hematopoietic cells that contribute to stem cell dormancy, quiescence, self-renewal, and differentiation. HSC also exist in resting spleen of several species, although their contribution to hematopoiesis under steady-state conditions is unknown. The spleen can however undergo extramedullary hematopoiesis (EMH) triggered by physiological stress or disease. With the loss of bone marrow niches in aging and disease, the spleen as an alternative tissue site for hematopoiesis is an important consideration for future therapy, particularly during HSC transplantation. In terms of harnessing the spleen as a site for hematopoiesis, here the remarkable regenerative capacity of the spleen is considered with a view to forming additional or ectopic spleen tissue through cell engraftment. Studies in mice indicate the potential for such grafts to support the influx of hematopoietic cells leading to the development of normal spleen architecture. An important goal will be the formation of functional ectopic spleen tissue as an aid to hematopoietic recovery following clinical treatments that impact bone marrow. For example, expansion or replacement of niches could be considered where myeloablation ahead of HSC transplantation compromises treatment outcomes.
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Affiliation(s)
- Christie Short
- Clem Jones Centre for Regenerative Medicine, Bond University, Gold Coast, QLD, 4229, Australia
| | - Hong K Lim
- Clem Jones Centre for Regenerative Medicine, Bond University, Gold Coast, QLD, 4229, Australia
| | - Jonathan Tan
- Clem Jones Centre for Regenerative Medicine, Bond University, Gold Coast, QLD, 4229, Australia
| | - Helen C O'Neill
- Clem Jones Centre for Regenerative Medicine, Bond University, Gold Coast, QLD, 4229, Australia
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