1
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Ozonoff A, Jayavelu ND, Liu S, Melamed E, Milliren CE, Qi J, Geng LN, McComsey GA, Cairns CB, Baden LR, Schaenman J, Shaw AC, Samaha H, Seyfert-Margolis V, Krammer F, Rosen LB, Steen H, Syphurs C, Dandekar R, Shannon CP, Sekaly RP, Ehrlich LIR, Corry DB, Kheradmand F, Atkinson MA, Brakenridge SC, Higuita NIA, Metcalf JP, Hough CL, Messer WB, Pulendran B, Nadeau KC, Davis MM, Sesma AF, Simon V, van Bakel H, Kim-Schulze S, Hafler DA, Levy O, Kraft M, Bime C, Haddad EK, Calfee CS, Erle DJ, Langelier CR, Eckalbar W, Bosinger SE, Peters B, Kleinstein SH, Reed EF, Augustine AD, Diray-Arce J, Maecker HT, Altman MC, Montgomery RR, Becker PM, Rouphael N. Features of acute COVID-19 associated with post-acute sequelae of SARS-CoV-2 phenotypes: results from the IMPACC study. Nat Commun 2024; 15:216. [PMID: 38172101 PMCID: PMC10764789 DOI: 10.1038/s41467-023-44090-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 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: 03/17/2023] [Accepted: 11/29/2023] [Indexed: 01/05/2024] Open
Abstract
Post-acute sequelae of SARS-CoV-2 (PASC) is a significant public health concern. We describe Patient Reported Outcomes (PROs) on 590 participants prospectively assessed from hospital admission for COVID-19 through one year after discharge. Modeling identified 4 PRO clusters based on reported deficits (minimal, physical, mental/cognitive, and multidomain), supporting heterogenous clinical presentations in PASC, with sub-phenotypes associated with female sex and distinctive comorbidities. During the acute phase of disease, a higher respiratory SARS-CoV-2 viral burden and lower Receptor Binding Domain and Spike antibody titers were associated with both the physical predominant and the multidomain deficit clusters. A lower frequency of circulating B lymphocytes by mass cytometry (CyTOF) was observed in the multidomain deficit cluster. Circulating fibroblast growth factor 21 (FGF21) was significantly elevated in the mental/cognitive predominant and the multidomain clusters. Future efforts to link PASC to acute anti-viral host responses may help to better target treatment and prevention of PASC.
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Affiliation(s)
- Al Ozonoff
- Clinical & Data Coordinating Center (CDCC), Precision Vaccines Program, Boston Children's Hospital, Boston, MA, USA
| | | | - Shanshan Liu
- Clinical & Data Coordinating Center (CDCC), Precision Vaccines Program, Boston Children's Hospital, Boston, MA, USA
| | | | - Carly E Milliren
- Clinical & Data Coordinating Center (CDCC), Precision Vaccines Program, Boston Children's Hospital, Boston, MA, USA
| | - Jingjing Qi
- Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | | | - Grace A McComsey
- Case Western Reserve University and University Hospitals of Cleveland, Cleveland, OH, USA
| | | | - Lindsey R Baden
- Boston Clinical Site: Precision Vaccines Program, Boston Children's Hospital, Brigham and Women's Hospital, and Harvard Medical School, Boston, MA, USA
| | - Joanna Schaenman
- David Geffen School of Medicine at the University of California Los Angeles, Los Angeles, CA, USA
| | - Albert C Shaw
- Yale School of Medicine, and Yale School of Public Health, New Haven, CT, USA
| | | | | | | | - Lindsey B Rosen
- National Institute of Allergy and Infectious Diseases/National Institutes of Health, Bethesda, MD, USA
| | - Hanno Steen
- Boston Clinical Site: Precision Vaccines Program, Boston Children's Hospital, Brigham and Women's Hospital, and Harvard Medical School, Boston, MA, USA
| | - Caitlin Syphurs
- Clinical & Data Coordinating Center (CDCC), Precision Vaccines Program, Boston Children's Hospital, Boston, MA, USA
| | - Ravi Dandekar
- University of California San Francisco School of Medicine, San Francisco, CA, USA
| | - Casey P Shannon
- Centre for Heart Lung Innovation, Providence Research, St. Paul's Hospital, and the PROOF Centre of Excellence, Vancouver, BC, Canada
| | - Rafick P Sekaly
- Case Western Reserve University and University Hospitals of Cleveland, Cleveland, OH, USA
| | | | - David B Corry
- Baylor College of Medicine, and the Center for Translational Research on Inflammatory Diseases, Michael E. DeBakey VA Medical Center, Houston, TX, USA
| | - Farrah Kheradmand
- Baylor College of Medicine, and the Center for Translational Research on Inflammatory Diseases, Michael E. DeBakey VA Medical Center, Houston, TX, USA
| | - Mark A Atkinson
- University of Florida/University of South Florida, Tampa, FL, USA
| | | | | | - Jordan P Metcalf
- Oklahoma University Health Sciences Center, Oklahoma City, OK, USA
| | | | | | | | | | | | | | - Viviana Simon
- Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Harm van Bakel
- Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | | | - David A Hafler
- Yale School of Medicine, and Yale School of Public Health, New Haven, CT, USA
| | - Ofer Levy
- Boston Clinical Site: Precision Vaccines Program, Boston Children's Hospital, Brigham and Women's Hospital, and Harvard Medical School, Boston, MA, USA
| | | | | | - Elias K Haddad
- Drexel University/Tower Health Hospital, Philadelphia, PA, USA
| | - Carolyn S Calfee
- University of California San Francisco School of Medicine, San Francisco, CA, USA
| | - David J Erle
- University of California San Francisco School of Medicine, San Francisco, CA, USA
| | - Charles R Langelier
- University of California San Francisco School of Medicine, San Francisco, CA, USA
| | - Walter Eckalbar
- University of California San Francisco School of Medicine, San Francisco, CA, USA
| | | | - Bjoern Peters
- La Jolla Institute for Immunology, La Jolla, CA, USA
| | - Steven H Kleinstein
- Yale School of Medicine, and Yale School of Public Health, New Haven, CT, USA
| | - Elaine F Reed
- David Geffen School of Medicine at the University of California Los Angeles, Los Angeles, CA, USA
| | - Alison D Augustine
- National Institute of Allergy and Infectious Diseases/National Institutes of Health, Bethesda, MD, USA
| | - Joann Diray-Arce
- Clinical & Data Coordinating Center (CDCC), Precision Vaccines Program, Boston Children's Hospital, Boston, MA, USA
| | | | | | - Ruth R Montgomery
- Yale School of Medicine, and Yale School of Public Health, New Haven, CT, USA
| | - Patrice M Becker
- National Institute of Allergy and Infectious Diseases/National Institutes of Health, Bethesda, MD, USA
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Siles N, Schuler M, Maguire C, Amengor D, Nguyen A, Wilen R, Rogers J, Bazzi S, Caslin B, DiPasquale C, Abigania M, Olson E, Creaturo J, Hurley K, Triplett TA, Rousseau JF, Strakowski SM, Wylie D, Maynard J, Ehrlich LIR, Melamed E. SARS-CoV-2 Humoral Immune Responses in Convalescent Individuals Over 12 Months Reveal Severity-Dependent Antibody Dynamics. medRxiv 2023:2023.12.05.23299462. [PMID: 38106077 PMCID: PMC10723498 DOI: 10.1101/2023.12.05.23299462] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2023]
Abstract
Background Understanding the kinetics and longevity of antibody responses to SARS-CoV-2 is critical to informing strategies toward reducing Coronavirus disease 2019 (COVID-19) reinfections, and improving vaccination and therapy approaches. Methods We evaluated antibody titers against SARS-CoV-2 nucleocapsid (N), spike (S), and receptor binding domain (RBD) of spike in 98 convalescent participants who experienced asymptomatic, mild, moderate or severe COVID-19 disease and in 17 non-vaccinated, non-infected controls, using four different antibody assays. Participants were sampled longitudinally at 1, 3, 6, and 12 months post-SARS-CoV-2 positive PCR test. Findings Increasing acute COVID-19 disease severity correlated with higher anti-N and anti-RBD antibody titers throughout 12 months post-infection. Anti-N and anti-RBD titers declined over time in all participants, with the exception of increased anti-RBD titers post-vaccination, and the decay rates were faster in hospitalized compared to non-hospitalized participants. <50% of participants retained anti-N titers above control levels at 12 months, with non-hospitalized participants falling below control levels sooner. Nearly all hospitalized and non-hospitalized participants maintained anti-RBD titers above controls for up to 12 months, suggesting longevity of protection against severe reinfections. Nonetheless, by 6 months, few participants retained >50% of their 1-month anti-N or anti-RBD titers. Vaccine-induced increases in anti-RBD titers were greater in non-hospitalized relative to hospitalized participants. Early convalescent antibody titers correlated with age, but no association was observed between Post-Acute Sequelae of SARS-CoV-2 infection (PASC) status or acute steroid treatment and convalescent antibody titers. Interpretation Hospitalized participants developed higher anti-SARS-CoV-2 antibody titers relative to non-hospitalized participants, a difference that persisted throughout 12 months, despite the faster decline in titers in hospitalized participants. In both groups, while anti-N titers fell below control levels for at least half of the participants, anti-RBD titers remained above control levels for almost all participants over 12 months, demonstrating generation of long-lived antibody responses known to correlate with protection from severe disease across COVID-19 severities. Overall, our findings contribute to the evolving understanding of COVID-19 antibody dynamics. Funding Austin Public Health, NIAAA, Babson Diagnostics, Dell Medical School Startup.
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Affiliation(s)
- Nadia Siles
- Department of Neurology, Dell Medical School, University of Texas at Austin, Austin, Texas
| | - Maisey Schuler
- Department of Neurology, Dell Medical School, University of Texas at Austin, Austin, Texas
| | - Cole Maguire
- Department of Neurology, Dell Medical School, University of Texas at Austin, Austin, Texas
| | - Dzifa Amengor
- Department of Molecular Biosciences, University of Texas at Austin, Austin, Texas
| | - Annalee Nguyen
- Department of Chemical Engineering, University of Texas at Austin, Austin, Texas
| | - Rebecca Wilen
- Department of Chemical Engineering, University of Texas at Austin, Austin, Texas
| | - Jacob Rogers
- Department of Neurology, Dell Medical School, University of Texas at Austin, Austin, Texas
| | - Sam Bazzi
- Department of Neurology, Dell Medical School, University of Texas at Austin, Austin, Texas
| | - Blaine Caslin
- Department of Neurology, Dell Medical School, University of Texas at Austin, Austin, Texas
| | | | | | | | - Janelle Creaturo
- Department of Neurology, Dell Medical School, University of Texas at Austin, Austin, Texas
| | - Kerin Hurley
- Department of Neurology, Dell Medical School, University of Texas at Austin, Austin, Texas; Dell Seton Medical Center at the University of Texas, Austin, Texas
| | - Todd A Triplett
- Department of Oncology Dell Medical School, University of Texas at Austin, Austin, Texas; Department of Immunotherapeutics & Biotechnology, School of Pharmacy, Texas Tech University Health Sciences Center, Abilene, TX, USA
| | - Justin F Rousseau
- Department of Neurology, Dell Medical School, University of Texas at Austin, Austin, Texas; Department of Population Health, Dell Medical School, University of Texas at Austin, Austin, Texas
| | - Stephen M Strakowski
- Department of Psychiatry, Indiana University School of Medicine, Indianapolis; Department of Psychiatry, Dell Medical School, University of Texas at Austin, Austin, Texas
| | - Dennis Wylie
- Center for Biomedical Research Support, University of Texas at Austin, Austin Texas
| | - Jennifer Maynard
- Department of Chemical Engineering, University of Texas at Austin, Austin, Texas
| | - Lauren I R Ehrlich
- Department of Molecular Biosciences, University of Texas at Austin, Austin, Texas
| | - Esther Melamed
- Department of Neurology, Dell Medical School, University of Texas at Austin, Austin, Texas
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3
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Ozonoff A, Schaenman J, Jayavelu ND, Milliren CE, Calfee CS, Cairns CB, Kraft M, Baden LR, Shaw AC, Krammer F, van Bakel H, Esserman DA, Liu S, Sesma AF, Simon V, Hafler DA, Montgomery RR, Kleinstein SH, Levy O, Bime C, Haddad EK, Erle DJ, Pulendran B, Nadeau KC, Davis MM, Hough CL, Messer WB, Agudelo Higuita NI, Metcalf JP, Atkinson MA, Brakenridge SC, Corry D, Kheradmand F, Ehrlich LIR, Melamed E, McComsey GA, Sekaly R, Diray-Arce J, Peters B, Augustine AD, Reed EF, Altman MC, Becker PM, Rouphael N. Corrigendum to "Phenotypes of disease severity in a cohort of hospitalized COVID-19 patients: results from the IMPACC study" [eBioMedicine 83 (2022) 104208]. EBioMedicine 2023; 98:104860. [PMID: 37918220 PMCID: PMC10643088 DOI: 10.1016/j.ebiom.2023.104860] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2023] Open
Affiliation(s)
- Al Ozonoff
- Clinical & Data Coordinating Center (CDCC), Precision Vaccines Program, Boston Children's Hospital, Boston, MA, USA
| | - Joanna Schaenman
- David Geffen School of Medicine at the University of California Los Angeles, Los Angeles, CA, USA
| | | | - Carly E Milliren
- Clinical & Data Coordinating Center (CDCC), Precision Vaccines Program, Boston Children's Hospital, Boston, MA, USA
| | - Carolyn S Calfee
- University of California San Francisco School of Medicine, San Francisco, CA, USA
| | | | | | - Lindsey R Baden
- Boston Clinical Site: Precision Vaccines Program, Boston Children's Hospital, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Albert C Shaw
- Yale School of Medicine, Yale School of Public Health, New Haven, CT, USA
| | | | - Harm van Bakel
- Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Denise A Esserman
- Yale School of Medicine, Yale School of Public Health, New Haven, CT, USA
| | - Shanshan Liu
- Clinical & Data Coordinating Center (CDCC), Precision Vaccines Program, Boston Children's Hospital, Boston, MA, USA
| | | | - Viviana Simon
- Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - David A Hafler
- Yale School of Medicine, Yale School of Public Health, New Haven, CT, USA
| | - Ruth R Montgomery
- Yale School of Medicine, Yale School of Public Health, New Haven, CT, USA
| | | | - Ofer Levy
- Boston Clinical Site: Precision Vaccines Program, Boston Children's Hospital, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | | | - Elias K Haddad
- Drexel University/Tower Health Hospital, Philadelphia, PA, USA
| | - David J Erle
- University of California San Francisco School of Medicine, San Francisco, CA, USA
| | | | | | | | | | | | | | | | - Mark A Atkinson
- University of Florida, Gainesville and University of South Florida, Tampa, FL, USA
| | - Scott C Brakenridge
- University of Florida, Gainesville and University of South Florida, Tampa, FL, USA
| | - David Corry
- Baylor College of Medicine, The Center for Translational Research on Inflammatory Diseases, Michael E. DeBakey, Houston, TX, USA
| | - Farrah Kheradmand
- Baylor College of Medicine, The Center for Translational Research on Inflammatory Diseases, Michael E. DeBakey, Houston, TX, USA
| | | | | | | | | | - Joann Diray-Arce
- Clinical & Data Coordinating Center (CDCC), Precision Vaccines Program, Boston Children's Hospital, Boston, MA, USA
| | - Bjoern Peters
- La Jolla Institute for Immunology, La Jolla, CA, USA
| | - Alison D Augustine
- National Institute of Allergy and Infectious Diseases/National Institutes of Health, Bethesda, MD, USA
| | - Elaine F Reed
- David Geffen School of Medicine at the University of California Los Angeles, Los Angeles, CA, USA
| | | | - Patrice M Becker
- National Institute of Allergy and Infectious Diseases/National Institutes of Health, Bethesda, MD, USA
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4
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Gygi JP, Maguire C, Patel RK, Shinde P, Konstorum A, Shannon CP, Xu L, Hoch A, Jayavelu ND, Network I, Haddad EK, Reed EF, Kraft M, McComsey GA, Metcalf J, Ozonoff A, Esserman D, Cairns CB, Rouphael N, Bosinger SE, Kim-Schulze S, Krammer F, Rosen LB, van Bakel H, Wilson M, Eckalbar W, Maecker H, Langelier CR, Steen H, Altman MC, Montgomery RR, Levy O, Melamed E, Pulendran B, Diray-Arce J, Smolen KK, Fragiadakis GK, Becker PM, Augustine AD, Sekaly RP, Ehrlich LIR, Fourati S, Peters B, Kleinstein SH, Guan L. Integrated longitudinal multi-omics study identifies immune programs associated with COVID-19 severity and mortality in 1152 hospitalized participants. bioRxiv 2023:2023.11.03.565292. [PMID: 37986828 PMCID: PMC10659275 DOI: 10.1101/2023.11.03.565292] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2023]
Abstract
Hospitalized COVID-19 patients exhibit diverse clinical outcomes, with some individuals diverging over time even though their initial disease severity appears similar. A systematic evaluation of molecular and cellular profiles over the full disease course can link immune programs and their coordination with progression heterogeneity. In this study, we carried out deep immunophenotyping and conducted longitudinal multi-omics modeling integrating ten distinct assays on a total of 1,152 IMPACC participants and identified several immune cascades that were significant drivers of differential clinical outcomes. Increasing disease severity was driven by a temporal pattern that began with the early upregulation of immunosuppressive metabolites and then elevated levels of inflammatory cytokines, signatures of coagulation, NETosis, and T-cell functional dysregulation. A second immune cascade, predictive of 28-day mortality among critically ill patients, was characterized by reduced total plasma immunoglobulins and B cells, as well as dysregulated IFN responsiveness. We demonstrated that the balance disruption between IFN-stimulated genes and IFN inhibitors is a crucial biomarker of COVID-19 mortality, potentially contributing to the failure of viral clearance in patients with fatal illness. Our longitudinal multi-omics profiling study revealed novel temporal coordination across diverse omics that potentially explain disease progression, providing insights that inform the targeted development of therapies for hospitalized COVID-19 patients, especially those critically ill.
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5
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Lyu A, Humphrey RS, Nam SH, Durham TA, Hu Z, Arasappan D, Horton TM, Ehrlich LIR. Integrin signaling is critical for myeloid-mediated support of T-cell acute lymphoblastic leukemia. Nat Commun 2023; 14:6270. [PMID: 37805579 PMCID: PMC10560206 DOI: 10.1038/s41467-023-41925-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 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: 02/03/2022] [Accepted: 09/21/2023] [Indexed: 10/09/2023] Open
Abstract
We previously found that T-cell acute lymphoblastic leukemia (T-ALL) requires support from tumor-associated myeloid cells, which activate Insulin Like Growth Factor 1 Receptor (IGF1R) signaling in leukemic blasts. However, IGF1 is not sufficient to sustain T-ALL in vitro, implicating additional myeloid-mediated signals in leukemia progression. Here, we find that T-ALL cells require close contact with myeloid cells to survive. Transcriptional profiling and in vitro assays demonstrate that integrin-mediated cell adhesion activates downstream focal adhesion kinase (FAK)/ proline-rich tyrosine kinase 2 (PYK2), which are required for myeloid-mediated T-ALL support, partly through activation of IGF1R. Blocking integrin ligands or inhibiting FAK/PYK2 signaling diminishes leukemia burden in multiple organs and confers a survival advantage in a mouse model of T-ALL. Inhibiting integrin-mediated adhesion or FAK/PYK2 also reduces survival of primary patient T-ALL cells co-cultured with myeloid cells. Furthermore, elevated integrin pathway gene signatures correlate with higher FAK signaling and myeloid gene signatures and are associated with an inferior prognosis in pediatric T-ALL patients. Together, these findings demonstrate that integrin activation and downstream FAK/PYK2 signaling are important mechanisms underlying myeloid-mediated support of T-ALL progression.
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Affiliation(s)
- Aram Lyu
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX, USA
| | - Ryan S Humphrey
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX, USA
| | - Seo Hee Nam
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX, USA
| | - Tyler A Durham
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX, USA
| | - Zicheng Hu
- Bakar Computational Health Sciences Institute, University of California, San Francisco, San Francisco, CA, USA
| | - Dhivya Arasappan
- Center for Biomedical Research Support, The University of Texas at Austin, Austin, TX, USA
| | - Terzah M Horton
- Department of Pediatrics, Baylor College of Medicine/Dan L. Duncan Cancer Center and Texas Children's Cancer Center, Houston, TX, USA
| | - Lauren I R Ehrlich
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX, USA.
- Department of Oncology, Livestrong Cancer Institutes, The University of Texas at Austin Dell Medical School, Austin, TX, USA.
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6
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Srinivasan J, Vasudev A, Shasha C, Selden HJ, Perez E, LaFleur B, Sinari SA, Krueger A, Richie ER, Ehrlich LIR. The initial age-associated decline in early T-cell progenitors reflects fewer pre-thymic progenitors and altered signals in the bone marrow and thymus microenvironments. Aging Cell 2023; 22:e13870. [PMID: 37221658 PMCID: PMC10410006 DOI: 10.1111/acel.13870] [Citation(s) in RCA: 0] [Impact Index Per Article: 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: 05/01/2022] [Revised: 05/01/2023] [Accepted: 05/03/2023] [Indexed: 05/25/2023] Open
Abstract
Age-related thymus involution results in decreased T-cell production, contributing to increased susceptibility to pathogens and reduced vaccine responsiveness. Elucidating mechanisms underlying thymus involution will inform strategies to restore thymopoiesis with age. The thymus is colonized by circulating bone marrow (BM)-derived thymus seeding progenitors (TSPs) that differentiate into early T-cell progenitors (ETPs). We find that ETP cellularity declines as early as 3 months (3MO) of age in mice. This initial ETP reduction could reflect changes in thymic stromal niches and/or pre-thymic progenitors. Using a multicongenic progenitor transfer approach, we demonstrate that the number of functional TSP/ETP niches does not diminish with age. Instead, the number of pre-thymic lymphoid progenitors in the BM and blood is substantially reduced by 3MO, although their intrinsic ability to seed and differentiate in the thymus is maintained. Additionally, Notch signaling in BM lymphoid progenitors and in ETPs diminishes by 3MO, suggesting reduced niche quality in the BM and thymus contribute to the early decline in ETPs. Together, these findings indicate that diminished BM lymphopoiesis and thymic stromal support contribute to an initial reduction in ETPs in young adulthood, setting the stage for progressive age-associated thymus involution.
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Affiliation(s)
- Jayashree Srinivasan
- Department of Molecular BiosciencesThe University of Texas at AustinAustinTexasUnited States
| | - Anusha Vasudev
- Department of Epigenetics and Molecular CarcinogenesisThe University of Texas MD Anderson Cancer CenterHoustonTexasUnited States
| | - Carolyn Shasha
- Vaccine and Infectious Disease DivisionFred Hutchinson Cancer CenterSeattleWashingtonUnited States
| | - Hilary J. Selden
- Department of Molecular BiosciencesThe University of Texas at AustinAustinTexasUnited States
| | - Encarnacion Perez
- Department of Epigenetics and Molecular CarcinogenesisThe University of Texas MD Anderson Cancer CenterHoustonTexasUnited States
| | - Bonnie LaFleur
- Center for Biomedical Informatics and StatisticsThe University of ArizonaTucsonArizonaUnited States
| | - Shripad A. Sinari
- Center for Biomedical Informatics and StatisticsThe University of ArizonaTucsonArizonaUnited States
| | - Andreas Krueger
- Molecular ImmunologyJustus‐Liebig‐University GiessenGiessenGermany
| | - Ellen R. Richie
- Department of Epigenetics and Molecular CarcinogenesisThe University of Texas MD Anderson Cancer CenterHoustonTexasUnited States
| | - Lauren I. R. Ehrlich
- Department of Molecular BiosciencesThe University of Texas at AustinAustinTexasUnited States
- Department of OncologyLivestrong Cancer Institutes, Dell Medical School at The University of Texas at AustinAustinTexasUnited States
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7
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Li Y, Guaman Tipan P, Selden HJ, Srinivasan J, Hale LP, Ehrlich LIR. CCR4 and CCR7 differentially regulate thymocyte localization with distinct outcomes for central tolerance. eLife 2023; 12:80443. [PMID: 37266571 DOI: 10.7554/elife.80443] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Accepted: 06/01/2023] [Indexed: 06/03/2023] Open
Abstract
Central tolerance ensures autoreactive T cells are eliminated or diverted to the regulatory T cell lineage, thus preventing autoimmunity. To undergo central tolerance, thymocytes must enter the medulla to test their TCRs for autoreactivity against the diverse self-antigens displayed by antigen presenting cells (APCs). While CCR7 is known to promote thymocyte medullary entry and negative selection, our previous studies implicate CCR4 in these processes, raising the question of whether CCR4 and CCR7 play distinct or redundant roles in central tolerance. Here, synchronized positive selection assays, 2-photon timelapse microscopy, and quantification of TCR-signaled apoptotic thymocytes, demonstrate that CCR4 and CCR7 promote medullary accumulation and central tolerance of distinct post-positive selection thymocyte subsets in mice. CCR4 is upregulated within hours of positive selection signaling and promotes medullary entry and clonal deletion of immature post-positive selection thymocytes. In contrast, CCR7 is expressed several days later and is required for medullary localization and negative selection of mature thymocytes. In addition, CCR4 and CCR7 differentially enforce self-tolerance, with CCR4 enforcing tolerance to self-antigens presented by activated APCs, which express CCR4 ligands. Our findings show that CCR7 expression is not synonymous with medullary localization and support a revised model of central tolerance in which CCR4 and CCR7 promote early and late stages of negative selection, respectively, via interactions with distinct APC subsets.
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Affiliation(s)
- Yu Li
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, United States
| | - Pablo Guaman Tipan
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, United States
| | - Hilary J Selden
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, United States
| | - Jayashree Srinivasan
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, United States
| | - Laura P Hale
- Department of Pathology, Duke University, Durham, United States
| | - Lauren I R Ehrlich
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, United States
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8
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Bazzi SA, Maguire C, Holay N, Geltman J, Hurley K, DiPasquale C, Abigania M, Olson E, Ehrlich LIR, Triplett TA, Melamed E. Longitudinal COVID-19 immune trajectories in patients with neurological autoimmunity on anti-CD20 therapy. Mult Scler Relat Disord 2022; 68:104195. [PMID: 36223705 PMCID: PMC9511881 DOI: 10.1016/j.msard.2022.104195] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2022] [Revised: 09/21/2022] [Accepted: 09/23/2022] [Indexed: 12/15/2022]
Abstract
BACKGROUND AND OBJECTIVES During the COVID-19 pandemic, B cell depleting therapies pose a clinical concern for patients with neuroimmune conditions, as patients may not mount a sufficient immune response to SARS-CoV-2 infection and vaccinations. Studies to-date have reported conflicting results on the degree of antibody production post-SARS-CoV-2 infection and vaccinations in B cell depleted patients, focusing primarily on short-term immune profiling. Our objective was to follow longitudinal immune responses in COVID-19 B cell depleted patients with neuroimmune disorders post-COVID-19 and SARS-CoV-2-vaccination. METHODS CD20 B cell depleted autoimmune patients and age/sex-matched controls positive for SARS-CoV-2 were recruited at Dell Medical School, UT Austin between 2020 and 2021, followed prospectively for 12 months and evaluated at multiple time points for spike S1 receptor binding domain (RBD) antibody titers, B and T cell composition, and frequency of T cells specific for SARS-CoV-2 antigens. RESULTS Immune responses post-SARS-CoV-2 infection and vaccination were evaluated in a cohort of COVID-19 B cell depleted neuroimmune patients (n = 5), COVID-19 non-B cell depleted autoimmune patients (n = 15), COVID-19 immunocompetent patients (n = 117), and healthy controls (n = 6) for a total of 259 samples in 137 participants. 4/5 B cell-depleted patients developed detectable anti-spike RBD antibodies, which were boosted by vaccination in 2 patients. While spike RBD antibodies were associated with presence of CD20+ B cells, very few B cells were required. In contrast, patients whose B cell compartment primarily consisted of CD19+CD20- Bcells during acute COVID-19 disease or vaccination did not seroconvert. Interestingly, circulating Bcells in B cell depleted patients were significantly CD38high with co-expression of CD24 and CD27, indicating that B cell depletion may impact B cell activation patterns. Additionally, all B cell depleted patients mounted a sustained T cell response to SARS-CoV-2 antigens, regardless of seroconversion. Specifically, all patients developed naïve, central memory, effector memory, and effector memory RA+ T cells, suggesting intact T cell memory conversion in B cell depleted patients compared to controls. DISCUSSION We present the longest COVID-19 immune profiling analysis to date in B cell depleted patients, demonstrating that both humoral and cellular immune responses can be generated and sustained up to 12 months post SARS-CoV-2 infection and vaccination. Notably, failure to establish humoral immunity did not result in severe disease. We also highlight specific T and B cell signatures that could be used as clinical biomarkers to advise patients on timing of SARS-CoV-2 vaccinations.
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Affiliation(s)
- Sam A Bazzi
- Department of Neurology, Dell Medical School, University of Texas at Austin, Austin, TX, United States
| | - Cole Maguire
- Department of Neurology, Dell Medical School, University of Texas at Austin, Austin, TX, United States
| | - Nisha Holay
- Department of Oncology Dell Medical School, University of Texas at Austin, Austin, TX, United States
| | - Janelle Geltman
- Department of Neurology, Dell Medical School, University of Texas at Austin, Austin, TX, United States
| | - Kerin Hurley
- Department of Neurology, Dell Medical School, University of Texas at Austin, Austin, TX, United States
| | | | | | - Eric Olson
- Babson Diagnostics, Austin, TX, United States
| | - Lauren I R Ehrlich
- Department of Oncology Dell Medical School, University of Texas at Austin, Austin, TX, United States; Department of Molecular Biosciences, University of Texas at Austin, Austin, TX, United States
| | - Todd A Triplett
- Department of Oncology Dell Medical School, University of Texas at Austin, Austin, TX, United States
| | - Esther Melamed
- Department of Neurology, Dell Medical School, University of Texas at Austin, Austin, TX, United States.
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9
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Lancaster JN, Keatinge‐Clay DE, Srinivasan J, Li Y, Selden HJ, Nam S, Richie ER, Ehrlich LIR. Central tolerance is impaired in the middle-aged thymic environment. Aging Cell 2022; 21:e13624. [PMID: 35561351 PMCID: PMC9197411 DOI: 10.1111/acel.13624] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [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: 01/25/2022] [Revised: 04/03/2022] [Accepted: 04/20/2022] [Indexed: 12/03/2022] Open
Abstract
One of the earliest hallmarks of immune aging is thymus involution, which not only reduces the number of newly generated and exported T cells, but also alters the composition and organization of the thymus microenvironment. Thymic T‐cell export continues into adulthood, yet the impact of thymus involution on the quality of newly generated T‐cell clones is not well established. Notably, the number and proportion of medullary thymic epithelial cells (mTECs) and expression of tissue‐restricted antigens (TRAs) decline with age, suggesting the involuting thymus may not promote efficient central tolerance. Here, we demonstrate that the middle‐aged thymic environment does not support rapid motility of medullary thymocytes, potentially diminishing their ability to scan antigen presenting cells (APCs) that display the diverse self‐antigens that induce central tolerance. Consistent with this possibility, thymic slice assays reveal that the middle‐aged thymic environment does not support efficient negative selection or regulatory T‐cell (Treg) induction of thymocytes responsive to either TRAs or ubiquitous self‐antigens. This decline in central tolerance is not universal, but instead impacts lower‐avidity self‐antigens that are either less abundant or bind to TCRs with moderate affinities. Additionally, the decline in thymic tolerance by middle age is accompanied by both a reduction in mTECs and hematopoietic APC subsets that cooperate to drive central tolerance. Thus, age‐associated changes in the thymic environment result in impaired central tolerance against moderate‐avidity self‐antigens, potentially resulting in export of increasingly autoreactive naive T cells, with a deficit of Treg counterparts by middle age.
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Affiliation(s)
- Jessica N. Lancaster
- Department of Molecular Biosciences The University of Texas at Austin Austin Texas USA
| | | | - Jayashree Srinivasan
- Department of Molecular Biosciences The University of Texas at Austin Austin Texas USA
| | - Yu Li
- Department of Molecular Biosciences The University of Texas at Austin Austin Texas USA
| | - Hilary J. Selden
- Department of Molecular Biosciences The University of Texas at Austin Austin Texas USA
| | - Seohee Nam
- Department of Molecular Biosciences The University of Texas at Austin Austin Texas USA
| | - Ellen R. Richie
- Department of Epigenetics and Molecular Carcinogenesis The University of Texas MD Anderson Cancer Center Houston Texas USA
| | - Lauren I. R. Ehrlich
- Department of Molecular Biosciences The University of Texas at Austin Austin Texas USA
- Department of Oncology Dell Medical School at The University of Texas at Austin Austin Texas USA
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10
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Srinivasan J, Lancaster JN, Singarapu N, Hale LP, Ehrlich LIR, Richie ER. Age-Related Changes in Thymic Central Tolerance. Front Immunol 2021; 12:676236. [PMID: 33968086 PMCID: PMC8100025 DOI: 10.3389/fimmu.2021.676236] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [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: 03/04/2021] [Accepted: 04/06/2021] [Indexed: 01/03/2023] Open
Abstract
Thymic epithelial cells (TECs) and hematopoietic antigen presenting cells (HAPCs) in the thymus microenvironment provide essential signals to self-reactive thymocytes that induce either negative selection or generation of regulatory T cells (Treg), both of which are required to establish and maintain central tolerance throughout life. HAPCs and TECs are comprised of multiple subsets that play distinct and overlapping roles in central tolerance. Changes that occur in the composition and function of TEC and HAPC subsets across the lifespan have potential consequences for central tolerance. In keeping with this possibility, there are age-associated changes in the cellular composition and function of T cells and Treg. This review summarizes changes in T cell and Treg function during the perinatal to adult transition and in the course of normal aging, and relates these changes to age-associated alterations in thymic HAPC and TEC subsets.
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Affiliation(s)
- Jayashree Srinivasan
- Department of Molecular Biosciences, Institute of Cellular and Molecular Biology, The University of Texas at Austin, Austin, TX, United States
| | | | - Nandini Singarapu
- Department of Epigenetics and Molecular Carcinogenesis, The University of Texas M.D. Anderson Cancer Center, Smithville, TX, United States
| | - Laura P Hale
- Department of Pathology, Duke University School of Medicine, Durham, NC, United States
| | - Lauren I R Ehrlich
- Department of Molecular Biosciences, Institute of Cellular and Molecular Biology, The University of Texas at Austin, Austin, TX, United States.,Livestrong Cancer Institutes, Dell Medical School, The University of Texas at Austin, Austin, TX, United States
| | - Ellen R Richie
- Department of Epigenetics and Molecular Carcinogenesis, The University of Texas M.D. Anderson Cancer Center, Smithville, TX, United States
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11
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Wei SC, Meijers WC, Axelrod ML, Anang NAAS, Screever EM, Wescott EC, Johnson DB, Whitley E, Lehmann L, Courand PY, Mancuso JJ, Himmel LE, Lebrun-Vignes B, Wleklinski MJ, Knollmann BC, Srinivasan J, Li Y, Atolagbe OT, Rao X, Zhao Y, Wang J, Ehrlich LIR, Sharma P, Salem JE, Balko JM, Moslehi JJ, Allison JP. A Genetic Mouse Model Recapitulates Immune Checkpoint Inhibitor-Associated Myocarditis and Supports a Mechanism-Based Therapeutic Intervention. Cancer Discov 2021; 11:614-625. [PMID: 33257470 PMCID: PMC8041233 DOI: 10.1158/2159-8290.cd-20-0856] [Citation(s) in RCA: 131] [Impact Index Per Article: 43.7] [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: 06/18/2020] [Revised: 10/08/2020] [Accepted: 11/23/2020] [Indexed: 11/16/2022]
Abstract
Immune checkpoint inhibitors (ICI) targeting CTLA4 or PD-1/PD-L1 have transformed cancer therapy but are associated with immune-related adverse events, including myocarditis. Here, we report a robust preclinical mouse model of ICI-associated myocarditis in which monoallelic loss of Ctla4 in the context of complete genetic absence of Pdcd1 leads to premature death in approximately half of mice. Premature death results from myocardial infiltration by T cells and macrophages and severe ECG abnormalities, closely recapitulating the clinical and pathologic hallmarks of ICI-associated myocarditis observed in patients. Using this model, we show that Ctla4 and Pdcd1 functionally interact in a gene dosage-dependent manner, providing a mechanism by which myocarditis arises with increased frequency in the setting of combination ICI therapy. We demonstrate that intervention with CTLA4-Ig (abatacept) is sufficient to ameliorate disease progression and additionally provide a case series of patients in which abatacept mitigates the fulminant course of ICI myocarditis. SIGNIFICANCE: We provide a preclinical model of ICI-associated myocarditis which recapitulates this clinical syndrome. Using this model, we demonstrate that CTLA4 and PD-1 (ICI targets) functionally interact for myocarditis development and that intervention with CTLA4-Ig (abatacept) attenuates myocarditis, providing mechanistic rationale and preclinical support for therapeutic clinical studies.See related commentary by Young and Bluestone, p. 537.This article is highlighted in the In This Issue feature, p. 521.
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Affiliation(s)
- Spencer C Wei
- Department of Immunology, The University of Texas MD Anderson Cancer Center, Houston, Texas.
| | - Wouter C Meijers
- Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Margaret L Axelrod
- Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Nana-Ama A S Anang
- Department of Immunology, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Elles M Screever
- Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Elizabeth C Wescott
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Douglas B Johnson
- Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Elizabeth Whitley
- Department of Veterinary Medicine and Surgery, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Lorenz Lehmann
- Department of Cardiology, University Hospital of Heidelberg, Heidelberg, Germany; German Center for Cardiovascular Research (DZHK), Partner Site Heidelberg/Mannheim, German Research Center (DKFZ), Heidelberg, Germany
| | - Pierre-Yves Courand
- Hospices Civils de Lyon, Service de cardiologie, IMMUCARE, Hôpital de la Croix-Rousse et Hôpital Lyon Sud, Lyon, France; Université de Lyon, CREATIS UMR INSERM U1044, INSA, Lyon France
| | - James J Mancuso
- Department of Immunology, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Lauren E Himmel
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Benedicte Lebrun-Vignes
- Department of Pharmacology, APHP. Sorbonne Université, INSERM, CIC-1901, UNICO-GRECO Cardiooncology Program, Paris, France
| | - Matthew J Wleklinski
- Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Bjorn C Knollmann
- Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Jayashree Srinivasan
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, Texas
| | - Yu Li
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, Texas
| | | | - Xiayu Rao
- Department of Bioinformatics and Computational Biology, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Yang Zhao
- Department of Bioinformatics and Computational Biology, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Jing Wang
- Department of Bioinformatics and Computational Biology, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Lauren I R Ehrlich
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, Texas.,Livestrong Cancer Institutes, Dell Medical School, The University of Texas at Austin, Austin, Texas
| | - Padmanee Sharma
- Department of Genitourinary Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas.,Parker Institute for Cancer Immunotherapy, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Joe-Elie Salem
- Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee.,Department of Pharmacology, APHP. Sorbonne Université, INSERM, CIC-1901, UNICO-GRECO Cardiooncology Program, Paris, France
| | - Justin M Balko
- Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee.,Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Javid J Moslehi
- Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee.
| | - James P Allison
- Department of Immunology, The University of Texas MD Anderson Cancer Center, Houston, Texas. .,Parker Institute for Cancer Immunotherapy, The University of Texas MD Anderson Cancer Center, Houston, Texas
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12
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Lyu A, Triplett TA, Godfrey WH, Nam SH, Ames RY, Hu Z, Sarang A, Selden HJ, Lee CH, Georgiou G, Horton TM, Ehrlich LIR. Tumor-associated myeloid cells provide critical support for T-ALL in vivo. The Journal of Immunology 2020. [DOI: 10.4049/jimmunol.204.supp.163.5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Abstract
T cell acute lymphoblastic leukemia (T-ALL) is a malignancy of immature T cells. Despite harboring multiple genetic alterations that drive disease, primary T-ALL cells require exogenous signals to survive. We previously reported that tumor-associated myeloid cells support survival of primary mouse T-ALL cells in vitro. However, the contribution of myeloid cells to T-ALL progression in vivo remains unclear. Here, we depleted phagocytic myeloid cells from leukemic mice, resulting in a significant reduction in tumor burden in multiple organs and prolonged survival. T-ALL burden also diminished following myeloid depletion in lymphodeficient mice, indicating that adaptive immunity was not required to eliminate T-ALL cells, thus suggesting tumor-associated myeloid cells could directly support T-ALL growth. Consistent with this possibility, multiple subsets of tumor-associated myeloid cells support survival of mouse and primary patient T-ALL cells in vitro. Acute myeloid depletion reduced activation of several pathways regulating cell survival in T-ALL cells, implicating these pathways in promoting T-ALL progression in vivo. Computational analysis of published datasets shows an association between enriched macrophage gene signatures and poor prognosis in T-ALL patients, further implicating a pro-tumor role for myeloid cells. Together, our results indicate that an altered myeloid compartment directly promotes T-ALL progression at divergent T-ALL sites in vivo.
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Affiliation(s)
- Aram Lyu
- 1Univ. of Texas, Austin, Department of Molecular Biosciences
| | - Todd A. Triplett
- 1Univ. of Texas, Austin, Department of Molecular Biosciences
- 2Univ. of Texas, Austin, Dell Medical School
| | | | - Seo Hee Nam
- 1Univ. of Texas, Austin, Department of Molecular Biosciences
| | - Rachel Y. Ames
- 1Univ. of Texas, Austin, Department of Molecular Biosciences
| | - Zicheng Hu
- 3Univ. of California, San Francisco, Bakar Computational Health Sciences Institute
| | - Adviti Sarang
- 1Univ. of Texas, Austin, Department of Molecular Biosciences
| | | | - Chang-Han Lee
- 4Univ. of Texas, Austin, Department of Chemical Engineering
| | | | - Terzah M. Horton
- 5Baylor College of Medicine/Dan L. Duncan Cancer Center and Texas Children’s Cancer Center, Department of Pediatrics
| | - Lauren I. R. Ehrlich
- 1Univ. of Texas, Austin, Department of Molecular Biosciences
- 2Univ. of Texas, Austin, Dell Medical School
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13
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Lancaster JN, Thyagarajan HM, Srinivasan J, Li Y, Hu Z, Ehrlich LIR. Live-cell imaging reveals the relative contributions of antigen-presenting cell subsets to thymic central tolerance. Nat Commun 2019; 10:2220. [PMID: 31101805 PMCID: PMC6525199 DOI: 10.1038/s41467-019-09727-4] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2018] [Accepted: 03/18/2019] [Indexed: 12/31/2022] Open
Abstract
Both medullary thymic epithelial cells (mTEC) and dendritic cells (DC) present tissue-restricted antigens (TRA) to thymocytes to induce central tolerance, but the relative contributions of these antigen-presenting cell (APC) subsets remain unresolved. Here we developed a two-photon microscopy approach to observe thymocytes interacting with intact APCs presenting TRAs. We find that mTECs and DCs cooperate extensively to induce tolerance, with their relative contributions regulated by the cellular form of the TRA and the class of major histocompatibility complex (MHC) on which antigen is presented. Even when TRA expression is restricted to mTECs, DCs still present self-antigens at least as frequently as mTECs. Notably, the DC subset cDC2 efficiently acquires secreted mTEC-derived TRAs for cross-presentation on MHC-I. By directly imaging interactions between thymocytes and APCs, while monitoring intracellular signaling, this study reveals that distinct DC subsets and AIRE+ mTECs contribute substantially to presentation of diverse self-antigens for establishing central tolerance.
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Affiliation(s)
- J N Lancaster
- Department of Molecular Biosciences, Institute of Cellular and Molecular Biology, The University of Texas at Austin, 100 E. 24th Street A5000, Austin, TX, 78712, USA
| | - H M Thyagarajan
- Department of Molecular Biosciences, Institute of Cellular and Molecular Biology, The University of Texas at Austin, 100 E. 24th Street A5000, Austin, TX, 78712, USA
| | - J Srinivasan
- Department of Molecular Biosciences, Institute of Cellular and Molecular Biology, The University of Texas at Austin, 100 E. 24th Street A5000, Austin, TX, 78712, USA
| | - Y Li
- Department of Molecular Biosciences, Institute of Cellular and Molecular Biology, The University of Texas at Austin, 100 E. 24th Street A5000, Austin, TX, 78712, USA
| | - Z Hu
- Department of Molecular Biosciences, Institute of Cellular and Molecular Biology, The University of Texas at Austin, 100 E. 24th Street A5000, Austin, TX, 78712, USA
| | - L I R Ehrlich
- Department of Molecular Biosciences, Institute of Cellular and Molecular Biology, The University of Texas at Austin, 100 E. 24th Street A5000, Austin, TX, 78712, USA.
- Livestrong Cancer Institutes, Dell Medical School, The University of Texas at Austin, Austin, TX, 78712, USA.
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14
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Singarapu N, Ma K, Reeh KAG, Shen J, Lancaster JN, Yi S, Xie H, Orkin SH, Manley NR, Ehrlich LIR, Jiang N, Richie ER. Polycomb Repressive Complex 2 is essential for development and maintenance of a functional TEC compartment. Sci Rep 2018; 8:14335. [PMID: 30254371 PMCID: PMC6156232 DOI: 10.1038/s41598-018-32729-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2018] [Accepted: 09/12/2018] [Indexed: 12/15/2022] Open
Abstract
Thymic epithelial cells (TEC) are essential for thymocyte differentiation and repertoire selection. Despite their indispensable role in generating functional T cells, the molecular mechanisms that orchestrate TEC development from endodermal progenitors in the third pharyngeal pouch (3rd PP) are not fully understood. We recently reported that the T-box transcription factor TBX1 negatively regulates TEC development. Although initially expressed throughout the 3rd PP, Tbx1 becomes downregulated in thymus-fated progenitors and when ectopically expressed impairs TEC progenitor proliferation and differentiation. Here we show that ectopic Tbx1 expression in thymus fated endoderm increases expression of Polycomb repressive complex 2 (PRC2) target genes in TEC. PRC2 is an epigenetic modifier that represses gene expression by catalyzing trimethylation of lysine 27 on histone H3. The increased expression of PRC2 target genes suggests that ectopic Tbx1 interferes with PRC2 activity and implicates PRC2 as an important regulator of TEC development. To test this hypothesis, we used Foxn1Cre to delete Eed, a PRC2 component required for complex stability and function in thymus fated 3rd PP endoderm. Proliferation and differentiation of fetal and newborn TEC were disrupted in the conditional knockout (EedCKO) mutants leading to severely dysplastic adult thymi. Consistent with PRC2-mediated transcriptional silencing, the majority of differentially expressed genes (DEG) were upregulated in EedCKO TEC. Moreover, a high frequency of EedCKO DEG overlapped with DEG in TEC that ectopically expressed Tbx1. These findings demonstrate that PRC2 plays a critical role in TEC development and suggest that Tbx1 expression must be downregulated in thymus fated 3rd PP endoderm to ensure optimal PRC2 function.
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Affiliation(s)
- Nandini Singarapu
- Department of Epigenetics and Molecular Carcinogenesis, The University of Texas M.D. Anderson Cancer Center, Science Park, Smithville, Texas, 78957, USA
| | - Keyue Ma
- Department of Biomedical Engineering, Cockrell School of Engineering, The University of Texas at Austin, Austin, TX, 78712, USA
| | - Kaitlin A G Reeh
- Department of Epigenetics and Molecular Carcinogenesis, The University of Texas M.D. Anderson Cancer Center, Science Park, Smithville, Texas, 78957, USA
| | - Jianjun Shen
- Department of Epigenetics and Molecular Carcinogenesis, The University of Texas M.D. Anderson Cancer Center, Science Park, Smithville, Texas, 78957, USA
| | - Jessica N Lancaster
- Department of Molecular Biosciences, Institute for Cellular and Molecular Biology, The University of Texas at Austin, Austin, TX, 78712, USA
| | - Song Yi
- Department of Oncology, Dell Medical School and Department of Biomedical Engineering, Cockrell School of Engineering, The University of Texas at Austin, Austin, TX, 78712, USA.,Livestrong Cancer Institutes, Dell Medical School, The University of Texas at Austin, Austin, TX, 78712, USA
| | - Huafeng Xie
- Division of Hematology/Oncology, Boston Children's Hospital, Boston, MA, 02115, USA.,Department of Pediatric Oncology, Dana-Farber Cancer Institute, Boston, MA, 02115, USA
| | - Stuart H Orkin
- Division of Hematology/Oncology, Boston Children's Hospital, Boston, MA, 02115, USA.,Department of Pediatric Oncology, Dana-Farber Cancer Institute, Boston, MA, 02115, USA.,Harvard Stem Cell Institute, Harvard University, Cambridge, MA, 02138, USA.,Howard Hughes Medical Institute, Boston, MA, 02115, USA
| | - Nancy R Manley
- Department of Genetics, Paul D. Coverdell Center, 500 DW Brooks Drive, University of Georgia, Athens, GA, 30602, USA
| | - Lauren I R Ehrlich
- Department of Molecular Biosciences, Institute for Cellular and Molecular Biology, The University of Texas at Austin, Austin, TX, 78712, USA.,Livestrong Cancer Institutes, Dell Medical School, The University of Texas at Austin, Austin, TX, 78712, USA
| | - Ning Jiang
- Department of Biomedical Engineering, Cockrell School of Engineering, The University of Texas at Austin, Austin, TX, 78712, USA
| | - Ellen R Richie
- Department of Epigenetics and Molecular Carcinogenesis, The University of Texas M.D. Anderson Cancer Center, Science Park, Smithville, Texas, 78957, USA.
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15
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Thyagarajan HM, Lancaster JN, Lira SA, Ehrlich LIR. CCR8 is expressed by post-positive selection CD4-lineage thymocytes but is dispensable for central tolerance induction. PLoS One 2018; 13:e0200765. [PMID: 30024927 PMCID: PMC6053179 DOI: 10.1371/journal.pone.0200765] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Accepted: 07/02/2018] [Indexed: 12/19/2022] Open
Abstract
Following positive selection, thymocytes migrate into the medulla where they encounter diverse self-antigens that induce central tolerance. Thymocytes expressing T cell receptors (TCRs) with high affinity for self-antigens displayed by medullary antigen presenting cells (APCs) undergo either negative selection or diversion to the regulatory T cell (Treg) lineage, thus ensuring maturation of non-autoreactive T cells. Because many self-antigens are expressed by only a small percentage of medullary thymic epithelial cells, thymocytes must enter the medulla and efficiently scan APCs therein to encounter the full array of self-antigens that induce central tolerance. Chemokine receptors play a critical role in promoting medullary entry and rapid motility of post-positive selection thymocytes. We found that the chemokine receptor CCR8 is expressed by post-positive selection CD4+ single positive (SP) thymocytes in mice, while the corresponding chemokine ligands are expressed by medullary APCs, and thus hypothesized that CCR8 would promote thymocyte medullary entry and/or rapid motility to induce negative selection. However, despite a subtle decline in thymocyte medullary accumulation and the presence of autoantibodies in aged CCR8-deficient mice, CCR8 was not required for thymocyte differentiation, rapid motility, or negative selection.
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Affiliation(s)
- Hiran M. Thyagarajan
- Department of Molecular Biosciences, Institute for Cellular and Molecular Biology, The University of Texas at Austin, Austin, Texas, United States of America
| | - Jessica N. Lancaster
- Department of Molecular Biosciences, Institute for Cellular and Molecular Biology, The University of Texas at Austin, Austin, Texas, United States of America
| | - Sergio A. Lira
- Immunology Institute, Icahn School of Medicine at Mount Sinai, New York, New York, United States of America
| | - Lauren I. R. Ehrlich
- Department of Molecular Biosciences, Institute for Cellular and Molecular Biology, The University of Texas at Austin, Austin, Texas, United States of America
- Livestrong Cancer Institutes, Dell Medical School, The University of Texas at Austin, Austin, Texas, United States of America
- * E-mail:
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16
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Hu Z, Li Y, Van Nieuwenhuijze A, Selden HJ, Jarrett AM, Sorace AG, Yankeelov TE, Liston A, Ehrlich LIR. CCR7 Modulates the Generation of Thymic Regulatory T Cells by Altering the Composition of the Thymic Dendritic Cell Compartment. Cell Rep 2018; 21:168-180. [PMID: 28978470 DOI: 10.1016/j.celrep.2017.09.016] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [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: 08/12/2016] [Revised: 07/21/2017] [Accepted: 09/01/2017] [Indexed: 12/29/2022] Open
Abstract
Upon recognition of auto-antigens, thymocytes are negatively selected or diverted to a regulatory T cell (Treg) fate. CCR7 is required for negative selection of auto-reactive thymocytes in the thymic medulla. Here, we describe an unanticipated contribution of CCR7 to intrathymic Treg generation. Ccr7-/- mice have increased Treg cellularity because of a hematopoietic but non-T cell autonomous CCR7 function. CCR7 expression by thymic dendritic cells (DCs) promotes survival of mature Sirpα- DCs. Thus, CCR7 deficiency results in apoptosis of Sirpα- DCs, which is counterbalanced by expansion of immature Sirpα+ DCs that efficiently induce Treg generation. CCR7 deficiency results in enhanced intrathymic generation of Tregs at the neonatal stage and in lymphopenic adults, when Treg differentiation is critical for establishing self-tolerance. Together, these results reveal a complex function for CCR7 in thymic tolerance induction, where CCR7 not only promotes negative selection but also governs intrathymic Treg generation via non-thymocyte intrinsic mechanisms.
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Affiliation(s)
- Zicheng Hu
- Department of Molecular Biosciences, Institute for Cellular and Molecular Biology, The University of Texas at Austin, Austin, TX 78712, USA
| | - Yu Li
- Department of Molecular Biosciences, Institute for Cellular and Molecular Biology, The University of Texas at Austin, Austin, TX 78712, USA
| | - Annemarie Van Nieuwenhuijze
- Translational Immunology Laboratory, VIB, Leuven 3000, Belgium; Department of Microbiology and Immunology, University of Leuven, Leuven 3000, Belgium
| | - Hilary J Selden
- Department of Molecular Biosciences, Institute for Cellular and Molecular Biology, The University of Texas at Austin, Austin, TX 78712, USA
| | - Angela M Jarrett
- Departments of Biomedical Engineering, The University of Texas at Austin, Austin, TX 78712, USA
| | - Anna G Sorace
- Departments of Biomedical Engineering, The University of Texas at Austin, Austin, TX 78712, USA; Diagnostic Medicine, The University of Texas at Austin, Austin, TX 78712, USA; Livestrong Cancer Institutes, Dell Medical School, The University of Texas at Austin, Austin, TX 78712, USA
| | - Thomas E Yankeelov
- Departments of Biomedical Engineering, The University of Texas at Austin, Austin, TX 78712, USA; Diagnostic Medicine, The University of Texas at Austin, Austin, TX 78712, USA; Institute for Computational Engineering and Sciences, The University of Texas at Austin, Austin, TX 78712, USA; Livestrong Cancer Institutes, Dell Medical School, The University of Texas at Austin, Austin, TX 78712, USA
| | - Adrian Liston
- Translational Immunology Laboratory, VIB, Leuven 3000, Belgium; Department of Microbiology and Immunology, University of Leuven, Leuven 3000, Belgium
| | - Lauren I R Ehrlich
- Department of Molecular Biosciences, Institute for Cellular and Molecular Biology, The University of Texas at Austin, Austin, TX 78712, USA; Livestrong Cancer Institutes, Dell Medical School, The University of Texas at Austin, Austin, TX 78712, USA.
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17
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Lancaster JN, Li Y, Ehrlich LIR. Chemokine-Mediated Choreography of Thymocyte Development and Selection. Trends Immunol 2017; 39:86-98. [PMID: 29162323 DOI: 10.1016/j.it.2017.10.007] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [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] [Revised: 10/19/2017] [Accepted: 10/27/2017] [Indexed: 12/30/2022]
Abstract
As they differentiate, thymocytes encounter spatially restricted cues critical for differentiation and selection of a functional, self-tolerant T cell repertoire. Sequential migration of developing T cells through distinct thymic microenvironments is enforced by the ordered expression of chemokine receptors. Herein, we provide an updated perspective on T cell differentiation through the lens of recent advances that illuminate the dynamics of chemokine-driven thymocyte migration, localization, and interactions with stromal cells. We consider these findings in the context of earlier groundwork exploring the contribution of chemokines to T cell development, recent advances regarding the specificity of chemokine signaling, and novel techniques for evaluating the T cell repertoire. We suggest future research should amalgamate visualization of localized cellular interactions with downstream molecular signals.
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Affiliation(s)
- Jessica N Lancaster
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX 78712, USA
| | - Yu Li
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX 78712, USA
| | - Lauren I R Ehrlich
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX 78712, USA.
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18
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Ki S, Thyagarajan HM, Hu Z, Lancaster JN, Ehrlich LIR. EBI2 contributes to the induction of thymic central tolerance in mice by promoting rapid motility of medullary thymocytes. Eur J Immunol 2017; 47:1906-1917. [PMID: 28741728 DOI: 10.1002/eji.201747020] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Revised: 06/14/2017] [Accepted: 07/21/2017] [Indexed: 11/08/2022]
Abstract
Maturing thymocytes enter the thymic medulla, where they encounter numerous self-antigens presented by antigen presenting cells (APCs). Those thymocytes that are strongly self-reactive undergo either negative selection or diversion into the regulatory T-cell lineage. Although the majority of the proteome is expressed in the medulla, many self-antigens are expressed by only a minor fraction of medullary APCs; thus, thymocytes must efficiently enter the medulla and scan APCs to ensure central tolerance. Chemokine receptors promote lymphocyte migration, organization within tissues, and interactions with APCs in lymphoid organs. The chemokine receptor EBI2 governs localization of T cells, B cells, and dendritic cells (DCs) during immune responses in secondary lymphoid organs. However, the role of EBI2 in thymocyte development has not been elucidated. Here, we demonstrate that EBI2 is expressed by murine CD4+ single positive (CD4SP) thymocytes and thymic DCs. EBI2 deficiency alters the TCR repertoire, but does not grossly impact thymocyte cellularity or subset distribution. EBI2 deficiency also impairs negative selection of OT-II TCR transgenic thymocytes responding to an endogenous self-antigen. Two-photon imaging revealed that EBI2 deficiency results in reduced migration and impaired medullary accumulation of CD4SP thymocytes. These data identify a role for EBI2 in promoting efficient thymic central tolerance.
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Affiliation(s)
- Sanghee Ki
- Department of Molecular Biosciences, Institute for Cellular and Molecular Biology, The University of Texas at Austin, Austin, TX, USA
| | - Hiran M Thyagarajan
- Department of Molecular Biosciences, Institute for Cellular and Molecular Biology, The University of Texas at Austin, Austin, TX, USA
| | - Zicheng Hu
- Department of Molecular Biosciences, Institute for Cellular and Molecular Biology, The University of Texas at Austin, Austin, TX, USA
| | - Jessica N Lancaster
- Department of Molecular Biosciences, Institute for Cellular and Molecular Biology, The University of Texas at Austin, Austin, TX, USA
| | - Lauren I R Ehrlich
- Department of Molecular Biosciences, Institute for Cellular and Molecular Biology, The University of Texas at Austin, Austin, TX, USA
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19
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Abstract
The detection of T cell activation is critical in many immunological assays. However, detecting T cell activation in live tissues remains a challenge due to highly noisy data. We developed a Bayesian probabilistic model to identify T cell activation based on calcium flux, a dramatic increase in intracellular calcium concentration that occurs during T cell activation. Because a T cell has unknown number of flux events, the implementation of posterior inference requires trans-dimensional posterior simulation. The model is able to detect calcium flux events at the single cell level from simulated data, as well as from noisy biological data.
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Affiliation(s)
- Zicheng Hu
- Department of Molecular Biosciences, School of Natural Sciences, The University of Texas at Austin, Austin, TX, 78712, U.S.A
| | - Jessica N Lancaster
- Department of Molecular Biosciences, School of Natural Sciences, The University of Texas at Austin, Austin, TX, 78712, U.S.A
| | - Lauren I R Ehrlich
- Department of Molecular Biosciences, School of Natural Sciences, The University of Texas at Austin, Austin, TX, 78712, U.S.A
| | - Peter Müller
- Department of Mathmatics, School of Natural Sciences, The University of Texas at Austin, Austin, TX, 78712, U.S.A
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20
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Lancaster JN, Ehrlich LIR. Analysis of Thymocyte Migration, Cellular Interactions, and Activation by Multiphoton Fluorescence Microscopy of Live Thymic Slices. Methods Mol Biol 2017; 1591:9-25. [PMID: 28349472 DOI: 10.1007/978-1-4939-6931-9_2] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Thymocytes migrate through discrete compartments within the thymus, engaging in cellular interactions essential for their differentiation into functional and self-tolerant T cells. Thus, understanding the temporal and spatial behavior of thymocytes within an intact thymic microenvironment is critical for elucidating processes governing T cell development. Towards this end, we describe methods for preparing thymic explant slices, in which the migration of thymocytes through three-dimensional space can be probed using time-lapse, multiphoton fluorescence microscopy. Thymocytes, enriched for developmental subsets of interest, are labeled with cytoplasmic fluorescent dyes, and seeded onto live thymic slices that express an endogenous, stromal cell-specific fluorescent reporter. In response to chemotactic cues produced by thymic stromal cells, the labeled thymocytes migrate withinthymic microenvironments and engage in cellular interactions that recapitulate a physiological system, whichcan be readily imaged. Here we describe specimen preparation that maintains the integrity of thymic structures. We also describe imaging protocols for acquiring multiple fluorochrome channels to enable detection of thymocyte:stromal cell interactions and quantification of relative intracellular calcium levels to monitor T cell receptor activation. Parameters for quantifying motility and interaction behaviors during data analysis are also briefly described. The thymic slice is a versatile tool for probing live cell behaviors and developing novel hypotheses not readily apparent by static experimental methods.
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Affiliation(s)
- Jessica N Lancaster
- Department of Molecular Biosciences, Institute for Cellular and Molecular Biology, The University of Texas at Austin, 2506 Speedway, A5000, Austin, TX, 78712, USA
| | - Lauren I R Ehrlich
- Department of Molecular Biosciences, Institute for Cellular and Molecular Biology, The University of Texas at Austin, 2506 Speedway, A5000, Austin, TX, 78712, USA.
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21
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Nath S, Christian L, Tan SY, Ki S, Ehrlich LIR, Poenie M. Dynein Separately Partners with NDE1 and Dynactin To Orchestrate T Cell Focused Secretion. J Immunol 2016; 197:2090-101. [PMID: 27534551 DOI: 10.4049/jimmunol.1600180] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Accepted: 07/14/2016] [Indexed: 11/19/2022]
Abstract
Helper and cytotoxic T cells accomplish focused secretion through the movement of vesicles toward the microtubule organizing center (MTOC) and translocation of the MTOC to the target contact site. In this study, using Jurkat cells and OT-I TCR transgenic primary murine CTLs, we show that the dynein-binding proteins nuclear distribution E homolog 1 (NDE1) and dynactin (as represented by p150(Glued)) form mutually exclusive complexes with dynein, exhibit nonoverlapping distributions in target-stimulated cells, and mediate different transport events. When Jurkat cells expressing a dominant negative form of NDE1 (NDE1-enhanced GFP fusion) were activated by Staphylococcus enterotoxin E-coated Raji cells, NDE1 and dynein failed to accumulate at the immunological synapse (IS) and MTOC translocation was inhibited. Knockdown of NDE1 in Jurkat cells or primary mouse CTLs also inhibited MTOC translocation and CTL-mediated killing. In contrast to NDE1, knockdown of p150(Glued), which depleted the alternative dynein/dynactin complex, resulted in impaired accumulation of CTLA4 and granzyme B-containing intracellular vesicles at the IS, whereas MTOC translocation was not affected. Depletion of p150(Glued) in CTLs also inhibited CTL-mediated lysis. We conclude that the NDE1/Lissencephaly 1 and dynactin complexes separately mediate two key components of T cell-focused secretion, namely translocation of the MTOC and lytic granules to the IS, respectively.
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Affiliation(s)
- Shubhankar Nath
- Department of Molecular Biosciences, University of Texas at Austin, Austin, TX 78712; and
| | - Laura Christian
- Department of Molecular Cell and Developmental Biology, University of Texas at Austin, Austin, TX 78712
| | - Sarah Youngsun Tan
- Department of Molecular Cell and Developmental Biology, University of Texas at Austin, Austin, TX 78712
| | - Sanghee Ki
- Department of Molecular Biosciences, University of Texas at Austin, Austin, TX 78712; and
| | - Lauren I R Ehrlich
- Department of Molecular Biosciences, University of Texas at Austin, Austin, TX 78712; and
| | - Martin Poenie
- Department of Molecular Biosciences, University of Texas at Austin, Austin, TX 78712; and
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22
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Thyagarajan HM, Hu Z, Ehrlich LIR. Defining the role of CCR8 in promoting thymocyte development and thymic epithelial homeostasis. The Journal of Immunology 2016. [DOI: 10.4049/jimmunol.196.supp.204.25] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Abstract
Generation of functional and self-tolerant T cells in the thymus is crucial to preventing autoimmune diseases. Medullary thymic epithelial cells (mTECs) and dendritic cells (DCs) present diverse auto-antigens to developing thymocytes; strong TCR reactivity in response to self-antigens causes thymocytes to undergo negative selection, eliminating autoreactive cells from the repertoire. Chemokine receptors expressed on the surface of developing thymocytes have been shown to promote accumulation of post-positive selection thymocytes in the medulla, where they may encounter mTECs and DCs presenting auto-antigens. CCR8 is highly expressed by post-positive selection CD4 thymocytes while its ligands, CCL1 and CCL8 are expressed by mTECs. Thus, CCR8 signaling may promote medullary entry of post-positive selection thymocytes and efficient interactions with mTECs and enforcing central tolerance. Our preliminary data indicate that CCR8−/− thymi have a reduced medullary area, implicating impaired thymocyte:mTEC interactions that impacts normal proliferation and differentiation of mTECs. Furthermore, 2-photon imaging reveals that CCR8 deficiency results in a significant increase in the path straightness of CD4 SP thymocytes, which could impact the efficiency of interactions with medullary stromal cells. Strikingly, CCR8 deficiency results in increased cellularity of CD4SP OTII TCR transgenic thymocytes in a wild-type host, suggesting CCR8 is critical for efficient clonal deletion to endogenous auto-antigens. Thus, our preliminary data indicate that CCR8 contributes to the migratory properties and stromal interactions of post-positive selection thymocytes that promote efficient negative selection.
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23
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Hu Z, Lancaster JN, Sasiponganan C, Ehrlich LIR. CCR4 promotes medullary entry and thymocyte-dendritic cell interactions required for central tolerance. ACTA ACUST UNITED AC 2015; 212:1947-65. [PMID: 26417005 PMCID: PMC4612092 DOI: 10.1084/jem.20150178] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2015] [Accepted: 08/20/2015] [Indexed: 11/24/2022]
Abstract
Hu et al. show that the chemokine receptor CCR4 is involved in thymocyte medullary entry, interactions with dendritic cells, and negative selection. In the absence of CCR4, central tolerance is not established, promoting autoimmunity. Autoimmunity results from a breakdown in central or peripheral tolerance. To establish central tolerance, developing T cells must enter the thymic medulla, where they scan antigen-presenting cells (APCs) displaying a diverse array of autoantigens. If a thymocyte is activated by a self-antigen, the cell undergoes either deletion or diversion into the regulatory T cell (T reg) lineage, thus maintaining self-tolerance. Mechanisms promoting thymocyte medullary entry and interactions with APCs are incompletely understood. CCR4 is poised to contribute to central tolerance due to its expression by post-positive selection thymocytes, and expression of its ligands by medullary thymic dendritic cells (DCs). Here, we use two-photon time-lapse microscopy to demonstrate that CCR4 promotes medullary entry of the earliest post-positive selection thymocytes, as well as efficient interactions between medullary thymocytes and DCs. In keeping with the contribution of thymic DCs to central tolerance, CCR4 is involved in regulating negative selection of polyclonal and T cell receptor (TCR) transgenic thymocytes. In the absence of CCR4, autoreactive T cells accumulate in secondary lymphoid organs and autoimmunity ensues. These studies reveal a previously unappreciated role for CCR4 in the establishment of central tolerance.
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Affiliation(s)
- Zicheng Hu
- Department of Molecular Biosciences, Institute for Cellular and Molecular Biology, The University of Texas at Austin, Austin, TX 78712
| | - Jessica N Lancaster
- Department of Molecular Biosciences, Institute for Cellular and Molecular Biology, The University of Texas at Austin, Austin, TX 78712
| | - Chayanit Sasiponganan
- Department of Molecular Biosciences, Institute for Cellular and Molecular Biology, The University of Texas at Austin, Austin, TX 78712
| | - Lauren I R Ehrlich
- Department of Molecular Biosciences, Institute for Cellular and Molecular Biology, The University of Texas at Austin, Austin, TX 78712
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24
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Hu Z, Lancaster JN, Ehrlich LIR. The Contribution of Chemokines and Migration to the Induction of Central Tolerance in the Thymus. Front Immunol 2015; 6:398. [PMID: 26300884 PMCID: PMC4528182 DOI: 10.3389/fimmu.2015.00398] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [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: 06/04/2015] [Accepted: 07/20/2015] [Indexed: 02/01/2023] Open
Abstract
As T cells develop, they migrate throughout the thymus where they undergo essential bi-directional signaling with stromal cells in distinct thymic microenvironments. Immature thymocyte progenitors are located in the thymic cortex. Following T cell receptor expression and positive selection, thymocytes undergo a dramatic transition: they become rapidly motile and relocate to the thymic medulla. Antigen-presenting cells (APCs) within the cortex and medulla display peptides derived from a wide array of self-proteins, which promote thymocyte self-tolerance. If a thymocyte is auto-reactive against such antigens, it undergoes either negative selection, via apoptosis, or differentiation into the regulatory T cell lineage. This induction of central tolerance is critical for prevention of autoimmunity. Chemokines and adhesion molecules play an essential role in tolerance induction, as they promote migration of developing thymocytes through the different thymic microenvironments and enhance interactions with APCs displaying self-antigens. Herein, we review the contribution of chemokines and other regulators of thymocyte localization and motility to T cell development, with a focus on their contribution to the induction of central tolerance.
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Affiliation(s)
- Zicheng Hu
- Ehrlich Laboratory, Department of Molecular Biosciences, Institute for Cellular and Molecular Biology, The University of Texas at Austin , Austin, TX , USA
| | - Jessica Naomi Lancaster
- Ehrlich Laboratory, Department of Molecular Biosciences, Institute for Cellular and Molecular Biology, The University of Texas at Austin , Austin, TX , USA
| | - Lauren I R Ehrlich
- Ehrlich Laboratory, Department of Molecular Biosciences, Institute for Cellular and Molecular Biology, The University of Texas at Austin , Austin, TX , USA
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25
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Brown KA, Yang X, Schipper D, Hall JW, DePue LJ, Gnanam AJ, Arambula JF, Jones JN, Swaminathan J, Dieye Y, Vadivelu J, Chandler DJ, Marcotte EM, Sessler JL, Ehrlich LIR, Jones RA. A self-assembling lanthanide molecular nanoparticle for optical imaging. Dalton Trans 2015; 44:2667-75. [PMID: 25512085 PMCID: PMC4401500 DOI: 10.1039/c4dt02646b] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [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] [Indexed: 11/21/2022]
Abstract
Chromophores that incorporate f-block elements have considerable potential for use in bioimaging applications because of their advantageous photophysical properties compared to organic dye, which are currently widely used. We are developing new classes of lanthanide-based self-assembling molecular nanoparticles as reporters for imaging and as multi-functional nanoprobes or nanosensors for use with biological samples. One class of these materials, which we call lanthanide "nano-drums", are homogeneous 4d-4f clusters approximately 25 to 30 Å in diameter. These are capable of emitting from the visible to near-infrared wavelengths. Here, we present the synthesis, crystal structure, photophysical properties and comparative cytotoxicity data for a 32 metal Eu-Cd nano-drum [Eu(8)Cd(24)L(12)(OAc)(48)] (1). We also explored the imaging capabilities of this nano-drum using epifluorescence, TIRF, and two-photon microscopy platforms.
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Affiliation(s)
- Katherine A. Brown
- Cavendish Laboratory, Department of Physics, University of Cambridge, Cambridge CB3 0HE, UK
- Department of Chemistry, The University of Texas at Austin, Austin, Texas 78712, USA
| | - Xiaoping Yang
- College of Chemistry and Materials Engineering, Wenzhou University, Wenzhou 325035, China
| | - Desmond Schipper
- Department of Chemistry, The University of Texas at Austin, Austin, Texas 78712, USA
| | - Justin W. Hall
- Department of Chemistry, The University of Texas at Austin, Austin, Texas 78712, USA
| | - Lauren J. DePue
- Department of Chemistry, The University of Texas at Austin, Austin, Texas 78712, USA
| | - Annie J. Gnanam
- Department of Chemistry, The University of Texas at Austin, Austin, Texas 78712, USA
| | - Jonathan F. Arambula
- Department of Chemistry, The University of Texas at Austin, Austin, Texas 78712, USA
| | - Jessica N. Jones
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, Texas 78712, USA
- Institute for Cellular and Molecular Biology, The University of Texas at Austin, Austin, Texas 78712, USA
| | - Jagannath Swaminathan
- Institute for Cellular and Molecular Biology, The University of Texas at Austin, Austin, Texas 78712, USA
- Center for Systems and Synthetic Biology, The University of Texas at Austin, Austin, Texas 78712, USA
| | - Yakhya Dieye
- Department of Medical Microbiology, University of Malaya, Kuala Lumpur 50603, Malaysia
| | - Jamuna Vadivelu
- Department of Medical Microbiology, University of Malaya, Kuala Lumpur 50603, Malaysia
| | | | - Edward M. Marcotte
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, Texas 78712, USA
- Institute for Cellular and Molecular Biology, The University of Texas at Austin, Austin, Texas 78712, USA
- Center for Systems and Synthetic Biology, The University of Texas at Austin, Austin, Texas 78712, USA
| | - Jonathan L. Sessler
- Department of Chemistry, The University of Texas at Austin, Austin, Texas 78712, USA
| | - Lauren I. R. Ehrlich
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, Texas 78712, USA
- Institute for Cellular and Molecular Biology, The University of Texas at Austin, Austin, Texas 78712, USA
| | - Richard A. Jones
- Department of Chemistry, The University of Texas at Austin, Austin, Texas 78712, USA
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26
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Norrie JL, Lewandowski JP, Bouldin CM, Amarnath S, Li Q, Vokes MS, Ehrlich LIR, Harfe BD, Vokes SA. Dynamics of BMP signaling in limb bud mesenchyme and polydactyly. Dev Biol 2014; 393:270-281. [PMID: 25034710 DOI: 10.1016/j.ydbio.2014.07.003] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [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: 05/16/2014] [Revised: 07/03/2014] [Accepted: 07/05/2014] [Indexed: 01/20/2023]
Abstract
Mutations in the Bone Morphogenetic Protein (BMP) pathway are associated with a range of defects in skeletal formation. Genetic analysis of BMP signaling requirements is complicated by the presence of three partially redundant BMPs that are required for multiple stages of limb development. We generated an inducible allele of a BMP inhibitor, Gremlin, which reduces BMP signaling. We show that BMPs act in a dose and time dependent manner in which early reduction of BMPs result in digit loss, while inhibiting overall BMP signaling between E10.5 and E11.5 allows polydactylous digit formation. During this period, inhibiting BMPs extends the duration of FGF signaling. Sox9 is initially expressed in normal digit ray domains but at reduced levels that correlate with the reduction in BMP signaling. The persistence of elevated FGF signaling likely promotes cell proliferation and survival, inhibiting the activation of Sox9 and secondarily, inhibiting the differentiation of Sox9-expressing chondrocytes. Our results provide new insights into the timing and clarify the mechanisms underlying BMP signaling during digit morphogenesis.
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Affiliation(s)
- Jacqueline L Norrie
- Department of Molecular Biosciences, Institute for Cellular and Molecular Biology, University of Texas at Austin, 2500 Speedway Stop A4800, Austin, TX 78712, USA
| | - Jordan P Lewandowski
- Department of Molecular Biosciences, Institute for Cellular and Molecular Biology, University of Texas at Austin, 2500 Speedway Stop A4800, Austin, TX 78712, USA
| | - Cortney M Bouldin
- Department of Molecular Genetics and Microbiology, College of Medicine, UF Genetics Institute, 2033 Mowry Road, Gainesville, Florida 32610, USA
| | - Smita Amarnath
- Department of Molecular Biosciences, Institute for Cellular and Molecular Biology, University of Texas at Austin, 2500 Speedway Stop A4800, Austin, TX 78712, USA
| | - Qiang Li
- Department of Molecular Biosciences, Institute for Cellular and Molecular Biology, University of Texas at Austin, 2500 Speedway Stop A4800, Austin, TX 78712, USA
| | - Martha S Vokes
- Department of Molecular Biosciences, Institute for Cellular and Molecular Biology, University of Texas at Austin, 2500 Speedway Stop A4800, Austin, TX 78712, USA
| | - Lauren I R Ehrlich
- Department of Molecular Biosciences, Institute for Cellular and Molecular Biology, University of Texas at Austin, 2500 Speedway Stop A4800, Austin, TX 78712, USA
| | - Brian D Harfe
- Department of Molecular Genetics and Microbiology, College of Medicine, UF Genetics Institute, 2033 Mowry Road, Gainesville, Florida 32610, USA
| | - Steven A Vokes
- Department of Molecular Biosciences, Institute for Cellular and Molecular Biology, University of Texas at Austin, 2500 Speedway Stop A4800, Austin, TX 78712, USA.
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27
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Jones RA, Gnanam AJ, Arambula JF, Jones JN, Swaminathan J, Yang X, Schipper D, Hall JW, DePue LJ, Dieye Y, Vadivelu J, Chandler DJ, Marcotte EM, Sessler JL, Ehrlich LIR, Brown KA. Lanthanide nano-drums: a new class of molecular nanoparticles for potential biomedical applications. Faraday Discuss 2014; 175:241-55. [PMID: 25284181 PMCID: PMC4407017 DOI: 10.1039/c4fd00117f] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [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] [Indexed: 11/21/2022]
Abstract
We are developing a new class of lanthanide-based self-assembling molecular nanoparticles as potential reporter molecules for imaging, and as multi-functional nanoprobes or nanosensors in diagnostic systems. These lanthanide "nano-drums" are homogeneous 4d-4f clusters approximately 25 to 30 Å in diameter that can emit from the visible to near-infrared (NIR) wavelengths. Here, we present syntheses, crystal structures, photophysical properties, and comparative cytotoxicity data for six nano-drums containing either Eu, Tb, Lu, Er, Yb or Ho. Imaging capabilities of these nano-drums are demonstrated using epifluorescence, total internal reflection fluorescence (TIRF), and two-photon microscopy. We discuss how these molecular nanoparticles can to be adapted for a range of assays, particularly by taking advantage of functionalization strategies with chemical moieties to enable conjugation to protein or nucleic acids.
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Affiliation(s)
- Richard A Jones
- Department of Chemistry, The University of Texas at Austin, 105 E. 24th St. Stop A5300, Austin, Texas 78712, USA.
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28
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Li J, Zhao Z, Carter C, Ehrlich LIR, Bedford MT, Richie ER. Coactivator-associated arginine methyltransferase 1 regulates fetal hematopoiesis and thymocyte development. J Immunol 2012; 190:597-604. [PMID: 23248263 DOI: 10.4049/jimmunol.1102513] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Coactivator-associated arginine methyltransferase 1 (CARM1) is a protein arginine methyltransferase that methylates histones and transcriptional regulators. We previously reported that the absence of CARM1 partially blocks thymocyte differentiation at embryonic day 18.5 (E18.5). In this study, we find that reduced thymopoiesis in Carm1(-/-) mice is due to a defect in the fetal hematopoietic compartment rather than in the thymic stroma. To determine the cellular basis for impaired thymopoiesis, we examined the number and function of fetal liver (FL) and bone marrow cells. Despite markedly reduced cellularity of hematopoietic progenitors in E18.5 bone marrow, the number of long-term hematopoietic stem cells and downstream subsets was not reduced in Carm1(-/-) E14.5 or E18.5 FL. Nevertheless, competitive reconstitution assays revealed a deficit in the ability of Carm1(-/-) FL cells to contribute to hematopoiesis. Furthermore, impaired differentiation of Carm1(-/-) FL cells in a CARM1-sufficient host showed that CARM1 is required cell autonomously in hematopoietic cells. Coculture of Carm1(-/-) FL cells on OP9-DL1 monolayers showed that CARM1 is required for survival of hematopoietic progenitors under conditions that promote differentiation. Taken together, this report demonstrates that CARM1 is a key epigenetic regulator of hematopoiesis that affects multiple lineages at various stages of differentiation.
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Affiliation(s)
- Jia Li
- Department of Molecular Carcinogenesis, The University of Texas MD Anderson Cancer Center, Smithville, TX 78957, USA
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Seita J, Sahoo D, Rossi DJ, Bhattacharya D, Serwold T, Inlay MA, Ehrlich LIR, Fathman JW, Dill DL, Weissman IL. Gene Expression Commons: an open platform for absolute gene expression profiling. PLoS One 2012; 7:e40321. [PMID: 22815738 PMCID: PMC3399844 DOI: 10.1371/journal.pone.0040321] [Citation(s) in RCA: 190] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2011] [Accepted: 06/07/2012] [Indexed: 12/29/2022] Open
Abstract
Gene expression profiling using microarrays has been limited to comparisons of gene expression between small numbers of samples within individual experiments. However, the unknown and variable sensitivities of each probeset have rendered the absolute expression of any given gene nearly impossible to estimate. We have overcome this limitation by using a very large number (>10,000) of varied microarray data as a common reference, so that statistical attributes of each probeset, such as the dynamic range and threshold between low and high expression, can be reliably discovered through meta-analysis. This strategy is implemented in a web-based platform named "Gene Expression Commons" (https://gexc.stanford.edu/) which contains data of 39 distinct highly purified mouse hematopoietic stem/progenitor/differentiated cell populations covering almost the entire hematopoietic system. Since the Gene Expression Commons is designed as an open platform, investigators can explore the expression level of any gene, search by expression patterns of interest, submit their own microarray data, and design their own working models representing biological relationship among samples.
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Affiliation(s)
- Jun Seita
- Institute for Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, Stanford, California, United States of America
- * E-mail: (JS); (ILW)
| | - Debashis Sahoo
- Institute for Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, Stanford, California, United States of America
| | - Derrick J. Rossi
- Institute for Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, Stanford, California, United States of America
| | - Deepta Bhattacharya
- Institute for Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, Stanford, California, United States of America
| | - Thomas Serwold
- Institute for Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, Stanford, California, United States of America
| | - Matthew A. Inlay
- Institute for Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, Stanford, California, United States of America
| | - Lauren I. R. Ehrlich
- Institute for Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, Stanford, California, United States of America
| | - John W. Fathman
- Institute for Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, Stanford, California, United States of America
| | - David L. Dill
- Department of Computer Science, Stanford University, Stanford, California, United States of America
| | - Irving L. Weissman
- Institute for Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, Stanford, California, United States of America
- * E-mail: (JS); (ILW)
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Ji H, Ehrlich LIR, Seita J, Murakami P, Doi A, Lindau P, Lee H, Aryee MJ, Irizarry RA, Kim K, Rossi DJ, Inlay MA, Serwold T, Karsunky H, Ho L, Daley GQ, Weissman IL, Feinberg AP. Comprehensive methylome map of lineage commitment from haematopoietic progenitors. Nature 2010; 467:338-42. [PMID: 20720541 PMCID: PMC2956609 DOI: 10.1038/nature09367] [Citation(s) in RCA: 474] [Impact Index Per Article: 33.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2010] [Accepted: 07/26/2010] [Indexed: 12/11/2022]
Abstract
Epigenetic modifications must underlie lineage-specific differentiation as terminally differentiated cells express tissue-specific genes, but their DNA sequence is unchanged. Hematopoiesis provides a well-defined model to study epigenetic modifications during cell-fate decisions, as multipotent progenitors (MPPs) differentiate into progressively restricted myeloid or lymphoid progenitors. While DNA methylation is critical for myeloid versus lymphoid differentiation, as demonstrated by the myeloerythroid bias in Dnmt1 hypomorphs1, a comprehensive DNA methylation map of hematopoietic progenitors, or of any multipotent/oligopotent lineage, does not exist. Here we examined 4.6 million CpG sites throughout the genome for MPPs, common lymphoid progenitors (CLPs), common myeloid progenitors (CMPs), granulocyte/macrophage progenitors (GMPs), and thymocyte progenitors (DN1, DN2, DN3). Dramatic epigenetic plasticity accompanied both lymphoid and myeloid restriction. Myeloid commitment involved less global DNA methylation than lymphoid commitment, supported functionally by myeloid skewing of progenitors following treatment with a DNA methyltransferase inhibitor. Differential DNA methylation correlated with gene expression more strongly at CpG island shores than CpG islands. Many examples of genes and pathways not previously known to be involved in choice between lymphoid/myeloid differentiation have been identified, such as Arl4c and Jdp2. Several transcription factors, including Meis1, were methylated and silenced during differentiation, suggesting a role in maintaining an undifferentiated state. Additionally, epigenetic modification of modifiers of the epigenome appears to be important in hematopoietic differentiation. Our results directly demonstrate that modulation of DNA methylation occurs during lineage-specific differentiation and defines a comprehensive map of the methylation and transcriptional changes that accompany myeloid versus lymphoid fate decisions.
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Affiliation(s)
- Hong Ji
- Center for Epigenetics and Department of Medicine, Johns Hopkins University School of Medicine, 570 Rangos, 725 N. Wolfe St., Baltimore, Maryland 21205, USA
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