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Yoo J, Dombrovski M, Mirshahidi P, Nern A, LoCascio SA, Zipursky SL, Kurmangaliyev YZ. Brain wiring determinants uncovered by integrating connectomes and transcriptomes. Curr Biol 2023; 33:3998-4005.e6. [PMID: 37647901 DOI: 10.1016/j.cub.2023.08.020] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Revised: 07/12/2023] [Accepted: 08/04/2023] [Indexed: 09/01/2023]
Abstract
Advances in brain connectomics have demonstrated the extraordinary complexity of neural circuits.1,2,3,4,5 Developing neurons encounter the axons and dendrites of many different neuron types and form synapses with only a subset of them. During circuit assembly, neurons express cell-type-specific repertoires comprising many cell adhesion molecules (CAMs) that can mediate interactions between developing neurites.6,7,8 Many CAM families have been shown to contribute to brain wiring in different ways.9,10 It has been challenging, however, to identify receptor-ligand pairs directly matching neurons with their synaptic targets. Here, we integrated the synapse-level connectome of the neural circuit11,12 with the developmental expression patterns7 and binding specificities of CAMs6,13 on pre- and postsynaptic neurons in the Drosophila visual system. To overcome the complexity of neural circuits, we focus on pairs of genetically related neurons that make differential wiring choices. In the motion detection circuit,14 closely related subtypes of T4/T5 neurons choose between alternative synaptic targets in adjacent layers of neuropil.12 This choice correlates with the matching expression in synaptic partners of different receptor-ligand pairs of the Beat and Side families of CAMs. Genetic analysis demonstrated that presynaptic Side-II and postsynaptic Beat-VI restrict synaptic partners to the same layer. Removal of this receptor-ligand pair disrupts layers and leads to inappropriate targeting of presynaptic sites and postsynaptic dendrites. We propose that different Side/Beat receptor-ligand pairs collaborate with other recognition molecules to determine wiring specificities in the fly brain. Combining transcriptomes, connectomes, and protein interactome maps allow unbiased identification of determinants of brain wiring.
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Affiliation(s)
- Juyoun Yoo
- Department of Biological Chemistry, Howard Hughes Medical Institute, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095, USA; Neuroscience Interdepartmental Program, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Mark Dombrovski
- Department of Biological Chemistry, Howard Hughes Medical Institute, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Parmis Mirshahidi
- Department of Biological Chemistry, Howard Hughes Medical Institute, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Aljoscha Nern
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - Samuel A LoCascio
- Department of Biological Chemistry, Howard Hughes Medical Institute, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - S Lawrence Zipursky
- Department of Biological Chemistry, Howard Hughes Medical Institute, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095, USA.
| | - Yerbol Z Kurmangaliyev
- Department of Biological Chemistry, Howard Hughes Medical Institute, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095, USA.
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2
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Kurmangaliyev YZ, Yoo J, LoCascio SA, Zipursky SL. Modular transcriptional programs separately define axon and dendrite connectivity. eLife 2019; 8:50822. [PMID: 31687928 PMCID: PMC6855804 DOI: 10.7554/elife.50822] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2019] [Accepted: 11/04/2019] [Indexed: 01/31/2023] Open
Abstract
Patterns of synaptic connectivity are remarkably precise and complex. Single-cell RNA sequencing has revealed a vast transcriptional diversity of neurons. Nevertheless, a clear logic underlying the transcriptional control of neuronal connectivity has yet to emerge. Here, we focused on Drosophila T4/T5 neurons, a class of closely related neuronal subtypes with different wiring patterns. Eight subtypes of T4/T5 neurons are defined by combinations of two patterns of dendritic inputs and four patterns of axonal outputs. Single-cell profiling during development revealed distinct transcriptional programs defining each dendrite and axon wiring pattern. These programs were defined by the expression of a few transcription factors and different combinations of cell surface proteins. Gain and loss of function studies provide evidence for independent control of different wiring features. We propose that modular transcriptional programs for distinct wiring features are assembled in different combinations to generate diverse patterns of neuronal connectivity.
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Affiliation(s)
- Yerbol Z Kurmangaliyev
- Department of Biological Chemistry, Howard Hughes Medical Institute, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, United States
| | - Juyoun Yoo
- Neuroscience Interdepartmental Program, University of California, Los Angeles, Los Angeles, United States
| | - Samuel A LoCascio
- Department of Biological Chemistry, Howard Hughes Medical Institute, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, United States
| | - S Lawrence Zipursky
- Department of Biological Chemistry, Howard Hughes Medical Institute, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, United States
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3
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Atabay KD, LoCascio SA, de Hoog T, Reddien PW. Self-organization and progenitor targeting generate stable patterns in planarian regeneration. Science 2018; 360:404-409. [PMID: 29545509 PMCID: PMC6135251 DOI: 10.1126/science.aap8179] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2017] [Accepted: 02/26/2018] [Indexed: 12/26/2022]
Abstract
During animal regeneration, cells must organize into discrete and functional systems. We show that self-organization, along with patterning cues, govern progenitor behavior in planarian regeneration. Surgical paradigms allowed the manipulation of planarian eye regeneration in predictable locations and numbers, generating alternative stable neuroanatomical states for wild-type animals with multiple functional ectopic eyes. We used animals with multiple ectopic eyes and eye transplantation to demonstrate that broad progenitor specification, combined with self-organization, allows anatomy maintenance during regeneration. We propose a model for regenerative progenitors involving (i) migratory targeting cues, (ii) self-organization into existing or regenerating eyes, and (iii) a broad zone, associated with coarse progenitor specification, in which eyes can be targeted by progenitors. These three properties help explain how tissues can be organized during regeneration.
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Affiliation(s)
- Kutay Deniz Atabay
- Whitehead Institute for Biomedical Research, Cambridge, MA 02142, USA
- Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
- Howard Hughes Medical Institute, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Samuel A LoCascio
- Whitehead Institute for Biomedical Research, Cambridge, MA 02142, USA
- Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
- Howard Hughes Medical Institute, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Thom de Hoog
- Whitehead Institute for Biomedical Research, Cambridge, MA 02142, USA
- Howard Hughes Medical Institute, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Peter W Reddien
- Whitehead Institute for Biomedical Research, Cambridge, MA 02142, USA.
- Howard Hughes Medical Institute, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
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Sprangers B, DeWolf S, Savage TM, Morokata T, Obradovic A, LoCascio SA, Shonts B, Zuber J, Lau SP, Shah R, Morris H, Steshenko V, Zorn E, Preffer FI, Olek S, Dombkowski DM, Turka LA, Colvin R, Winchester R, Kawai T, Sykes M. Origin of Enriched Regulatory T Cells in Patients Receiving Combined Kidney-Bone Marrow Transplantation to Induce Transplantation Tolerance. Am J Transplant 2017; 17:2020-2032. [PMID: 28251801 PMCID: PMC5519438 DOI: 10.1111/ajt.14251] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2016] [Revised: 02/14/2017] [Accepted: 02/22/2017] [Indexed: 01/25/2023]
Abstract
We examined tolerance mechanisms in patients receiving HLA-mismatched combined kidney-bone marrow transplantation (CKBMT) that led to transient chimerism under a previously published nonmyeloablative conditioning regimen (Immune Tolerance Network study 036). Polychromatic flow cytometry and high-throughput sequencing of T cell receptor-β hypervariable regions of DNA from peripheral blood regulatory T cells (Tregs) and CD4 non-Tregs revealed marked early enrichment of Tregs (CD3+ CD4+ CD25high CD127low Foxp3+ ) in blood that resulted from peripheral proliferation (Ki67+ ), possibly new thymic emigration (CD31+ ), and, in one tolerant subject, conversion from non-Tregs. Among recovering conventional T cells, central memory CD4+ and CD8+ cells predominated. A large proportion of the T cell clones detected in posttransplantation biopsy specimens by T cell receptor sequencing were detected in the peripheral blood and were not donor-reactive. Our results suggest that enrichment of Tregs by new thymic emigration and lymphopenia-driven peripheral proliferation in the early posttransplantation period may contribute to tolerance after CKBMT. Further, most conventional T cell clones detected in immunologically quiescent posttransplantation biopsy specimens appear to be circulating cells in the microvasculature rather than infiltrating T cells.
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Affiliation(s)
- Ben Sprangers
- Columbia Center for Translational Immunology, Department of Medicine, Columbia University Medical Center, New York, NY, USA,Department of Microbiology and Immunology, Laboratory of Experimental Transplantation, KU Leuven - University of Leuven, and Department of Nephrology, University Hospitals Leuven, Leuven, Belgium
| | - Susan DeWolf
- Columbia Center for Translational Immunology, Department of Medicine, Columbia University Medical Center, New York, NY, USA
| | - Thomas M. Savage
- Columbia Center for Translational Immunology, Department of Medicine, Columbia University Medical Center, New York, NY, USA
| | - Tatsuaki Morokata
- Center for Transplantation Sciences, Department of Surgery, Massachusetts General Hospital (MGH)/Harvard Medical School (HMS), Boston, MA, USA
| | - Aleksandar Obradovic
- Columbia Center for Translational Immunology, Department of Medicine, Columbia University Medical Center, New York, NY, USA
| | - Samuel A. LoCascio
- Columbia Center for Translational Immunology, Department of Medicine, Columbia University Medical Center, New York, NY, USA
| | - Brittany Shonts
- Columbia Center for Translational Immunology, Department of Medicine, Columbia University Medical Center, New York, NY, USA
| | - Julien Zuber
- Columbia Center for Translational Immunology, Department of Medicine, Columbia University Medical Center, New York, NY, USA
| | - Sai ping Lau
- Columbia Center for Translational Immunology, Department of Medicine, Columbia University Medical Center, New York, NY, USA
| | - Ravi Shah
- Columbia Center for Translational Immunology, Department of Medicine, Columbia University Medical Center, New York, NY, USA
| | - Heather Morris
- Columbia Center for Translational Immunology, Department of Medicine, Columbia University Medical Center, New York, NY, USA
| | - Valeria Steshenko
- Division of Rheumatology, Department of Medicine, Columbia University Medical Center, New York, NY, USA
| | - Emmanuel Zorn
- Columbia Center for Translational Immunology, Department of Medicine, Columbia University Medical Center, New York, NY, USA
| | | | - Sven Olek
- Epiontis Gmbh, Rudower Chaussee 29, 12489 Berlin, Germany
| | | | - Laurence A. Turka
- Center for Transplantation Sciences, Department of Surgery, Massachusetts General Hospital (MGH)/Harvard Medical School (HMS), Boston, MA, USA,Immune Tolerance Network, Seattle, WA, USA
| | | | - Robert Winchester
- Division of Rheumatology, Department of Medicine, Columbia University Medical Center, New York, NY, USA
| | - Tatsuo Kawai
- Transplantation Unit, Department of Surgery, MGH/HMS, Boston, MA, USA
| | - Megan Sykes
- Columbia Center for Translational Immunology, Department of Medicine, Columbia University Medical Center, New York, NY, USA,Center for Transplantation Sciences, Department of Surgery, Massachusetts General Hospital (MGH)/Harvard Medical School (HMS), Boston, MA, USA,Department of Microbiology and Immunology, Columbia University Medical Center, Columbia University, New York, NY, USA
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LoCascio SA, Lapan SW, Reddien PW. Eye Absence Does Not Regulate Planarian Stem Cells during Eye Regeneration. Dev Cell 2017; 40:381-391.e3. [PMID: 28245923 DOI: 10.1016/j.devcel.2017.02.002] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2016] [Revised: 01/06/2017] [Accepted: 02/01/2017] [Indexed: 12/28/2022]
Abstract
Dividing cells called neoblasts contain pluripotent stem cells and drive planarian flatworm regeneration from diverse injuries. A long-standing question is whether neoblasts directly sense and respond to the identity of missing tissues during regeneration. We used the eye to investigate this question. Surprisingly, eye removal was neither sufficient nor necessary for neoblasts to increase eye progenitor production. Neoblasts normally increase eye progenitor production following decapitation, facilitating regeneration. Eye removal alone, however, did not induce this response. Eye regeneration following eye-specific resection resulted from homeostatic rates of eye progenitor production and less cell death in the regenerating eye. Conversely, large head injuries that left eyes intact increased eye progenitor production. Large injuries also non-specifically increased progenitor production for multiple uninjured tissues. We propose a model for eye regeneration in which eye tissue production by planarian stem cells is not directly regulated by the absence of the eye itself.
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Affiliation(s)
- Samuel A LoCascio
- Whitehead Institute for Biomedical Research, Cambridge, MA 02142, USA; Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139, USA; Howard Hughes Medical Institute, MIT, Cambridge, MA 02139, USA
| | - Sylvain W Lapan
- Whitehead Institute for Biomedical Research, Cambridge, MA 02142, USA; Department of Biology, MIT, Cambridge, MA 02139, USA; Howard Hughes Medical Institute, MIT, Cambridge, MA 02139, USA
| | - Peter W Reddien
- Whitehead Institute for Biomedical Research, Cambridge, MA 02142, USA; Department of Biology, MIT, Cambridge, MA 02139, USA; Howard Hughes Medical Institute, MIT, Cambridge, MA 02139, USA.
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6
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Morris H, DeWolf S, Robins H, Sprangers B, LoCascio SA, Shonts BA, Kawai T, Wong W, Yang S, Zuber J, Shen Y, Sykes M. Tracking donor-reactive T cells: Evidence for clonal deletion in tolerant kidney transplant patients. Sci Transl Med 2015; 7:272ra10. [PMID: 25632034 DOI: 10.1126/scitranslmed.3010760] [Citation(s) in RCA: 175] [Impact Index Per Article: 19.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
T cell responses to allogeneic major histocompatibility complex antigens present a formidable barrier to organ transplantation, necessitating long-term immunosuppression to minimize rejection. Chronic rejection and drug-induced morbidities are major limitations that could be overcome by allograft tolerance induction. Tolerance was first intentionally induced in humans via combined kidney and bone marrow transplantation (CKBMT), but the mechanisms of tolerance in these patients are incompletely understood. We now establish an assay to identify donor-reactive T cells and test the role of deletion in tolerance after CKBMT. Using high-throughput sequencing of the T cell receptor B chain CDR3 region, we define a fingerprint of the donor-reactive T cell repertoire before transplantation and track those clones after transplant. We observed posttransplant reductions in donor-reactive T cell clones in three tolerant CKBMT patients; such reductions were not observed in a fourth, nontolerant, CKBMT patient or in two conventional kidney transplant recipients on standard immunosuppressive regimens. T cell repertoire turnover due to lymphocyte-depleting conditioning only partially accounted for the observed reductions in tolerant patients; in fact, conventional transplant recipients showed expansion of circulating donor-reactive clones, despite extensive repertoire turnover. Moreover, loss of donor-reactive T cell clones more closely associated with tolerance induction than in vitro functional assays. Our analysis supports clonal deletion as a mechanism of allograft tolerance in CKBMT patients. The results validate the contribution of donor-reactive T cell clones identified before transplant by our method, supporting further exploration as a potential biomarker of transplant outcomes.
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Affiliation(s)
- Heather Morris
- Columbia University Medical Center, New York, NY 10032, USA
| | - Susan DeWolf
- Columbia University Medical Center, New York, NY 10032, USA
| | - Harlan Robins
- Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA
| | - Ben Sprangers
- Columbia University Medical Center, New York, NY 10032, USA
| | | | | | - Tatsuo Kawai
- Massachusetts General Hospital, Boston, MA 02114, USA
| | - Waichi Wong
- Columbia University Medical Center, New York, NY 10032, USA
| | - Suxiao Yang
- Columbia University Medical Center, New York, NY 10032, USA
| | - Julien Zuber
- Columbia University Medical Center, New York, NY 10032, USA
| | - Yufeng Shen
- Columbia University Medical Center, New York, NY 10032, USA.
| | - Megan Sykes
- Columbia University Medical Center, New York, NY 10032, USA.
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Farris AB, Taheri D, Kawai T, Fazlollahi L, Wong W, Tolkoff-Rubin N, Spitzer TR, Iafrate AJ, Preffer FI, LoCascio SA, Sprangers B, Saidman S, Smith RN, Cosimi AB, Sykes M, Sachs DH, Colvin RB. Acute renal endothelial injury during marrow recovery in a cohort of combined kidney and bone marrow allografts. Am J Transplant 2011; 11:1464-77. [PMID: 21668634 PMCID: PMC3128680 DOI: 10.1111/j.1600-6143.2011.03572.x] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
An idiopathic capillary leak syndrome ('engraftment syndrome') often occurs in recipients of hematopoietic cells, manifested clinically by transient azotemia and sometimes fever and fluid retention. Here, we report the renal pathology in 10 recipients of combined bone marrow and kidney allografts. Nine developed graft dysfunction on day 10-16 and renal biopsies showed marked acute tubular injury, with interstitial edema, hemorrhage and capillary congestion, with little or no interstitial infiltrate (≤10%) and marked glomerular and peritubular capillary (PTC) endothelial injury and loss by electron microscopy. Two had transient arterial endothelial inflammation; and 2 had C4d deposition. The cells in capillaries were primarily CD68(+) MPO(+) mononuclear cells and CD3(+) CD8(+) T cells, the latter with a high proliferative index (Ki67(+) ). B cells (CD20(+) ) and CD4(+) T cells were not detectable, and NK cells were rare. XY FISH showed that CD45(+) cells in PTCs were of recipient origin. Optimal treatment remains to be defined; two recovered without additional therapy, six were treated with anti-rejection regimens. Except for one patient, who later developed thrombotic microangiopathy and one with acute humoral rejection, all fully recovered within 2-4 weeks. Graft endothelium is the primary target of this process, attributable to as yet obscure mechanisms, arising during leukocyte recovery.
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Affiliation(s)
- AB Farris
- Pathology Service, Massachusetts General Hospital (MGH), Boston, Massachusetts, United States, Pathology Department and Laboratory Medicine, Emory University, Atlanta, Georgia, United States, Harvard Medical School, Boston
| | - D Taheri
- Pathology Service, Massachusetts General Hospital (MGH), Boston, Massachusetts, United States, Harvard Medical School, Boston
| | - T Kawai
- Transplantation Unit, MGH, Boston, Harvard Medical School, Boston
| | - L Fazlollahi
- Pathology Service, Massachusetts General Hospital (MGH), Boston, Massachusetts, United States, Harvard Medical School, Boston
| | - W. Wong
- Medical Service, MGH, Boston, Harvard Medical School, Boston
| | - N Tolkoff-Rubin
- Medical Service, MGH, Boston, Harvard Medical School, Boston
| | - TR Spitzer
- Medical Service, MGH, Boston, Harvard Medical School, Boston
| | - AJ Iafrate
- Pathology Service, Massachusetts General Hospital (MGH), Boston, Massachusetts, United States, Harvard Medical School, Boston
| | - FI Preffer
- Pathology Service, Massachusetts General Hospital (MGH), Boston, Massachusetts, United States, Harvard Medical School, Boston
| | - SA LoCascio
- Transplantation Biology Research Center, MGH, Boston, Department of Medicine, Surgery, and Microbiology & Immunology, Columbia Center for Translational Immunology, Columbia University, New York City, New York, United States
| | - B Sprangers
- Department of Medicine, Surgery, and Microbiology & Immunology, Columbia Center for Translational Immunology, Columbia University, New York City, New York, United States
| | - S Saidman
- Pathology Service, Massachusetts General Hospital (MGH), Boston, Massachusetts, United States, Harvard Medical School, Boston
| | - RN Smith
- Pathology Service, Massachusetts General Hospital (MGH), Boston, Massachusetts, United States, Harvard Medical School, Boston
| | - AB Cosimi
- Transplantation Unit, MGH, Boston, Harvard Medical School, Boston
| | - M Sykes
- Transplantation Biology Research Center, MGH, Boston, Department of Medicine, Surgery, and Microbiology & Immunology, Columbia Center for Translational Immunology, Columbia University, New York City, New York, United States, Harvard Medical School, Boston
| | - DH Sachs
- Transplantation Biology Research Center, MGH, Boston, Harvard Medical School, Boston
| | - RB Colvin
- Pathology Service, Massachusetts General Hospital (MGH), Boston, Massachusetts, United States, Harvard Medical School, Boston
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LoCascio SA, Spinelli J, Kurtz J. Hematopoietic stem cell transplantation for the treatment of autoimmunity in type 1 diabetes. Curr Stem Cell Res Ther 2011; 6:29-37. [PMID: 20955158 DOI: 10.2174/157488811794480681] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2009] [Accepted: 11/03/2009] [Indexed: 11/22/2022]
Abstract
Type 1 diabetes (T1D) is an autoimmune disease that leads to the destruction of the insulin-producing pancreatic b cells. While there is no current cure, recent work in the field of allogeneic hematopoietic stem cell transplantation (HSCT) and the induction of mixed chimerism, a state in which multilineage hematopoietic populations of both recipient and donor co-exist, has demonstrated that it is possible to provide protection from disease onset, as well as reverse the autoimmune state in spontaneously diabetic mice. Furthermore, the establishment of mixed chimerism induces donor-specific tolerance, providing the potential to normalize glucose regulation via pancreatic islet transplantation without the requirement of life-long immunosuppression. Current studies are aimed at understanding the mechanisms involved in both the reversal of autoimmunity and the induction of tolerance, with the aim of moving this promising approach to curing T1D into the clinic.
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