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Branch DR. Warm autoimmune hemolytic anemia: new insights and hypotheses. Curr Opin Hematol 2023; 30:203-209. [PMID: 37497853 PMCID: PMC10552839 DOI: 10.1097/moh.0000000000000779] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/28/2023]
Abstract
PURPOSE OF REVIEW Warm autoimmune hemolytic anemia (wAIHA) is the most common of the immune hemolytic anemias. Although there are numerous case reports and reviews regarding this condition, some of the unusual and more recent findings have not been fully defined and may be contentious. This review will provide insight into the common specificity of the warm autoantibodies and hypothesize a novel mechanism of wAIHA, that is proposed to be linked to the controversial subject of red blood cell senescence. RECENT FINDINGS AND HYPOTHESES It is now well established that band 3 on the red blood cell is the main target of autoantibodies in wAIHA. wAIHA targets the older red blood cells (RBCs) in about 80% of cases and, recently, it has been shown that the RBCs in these patients are aging faster than normal. It has been proposed that in these 80% of patients, that the autoantibody recognizes the senescent red blood cell antigen on band 3. It is further hypothesized that this autoantibody's production and potency has been exacerbated by hypersensitization to the RBC senescent antigen, which is processed through the adaptive immune system to create the pathogenic autoantibody. Recent publications have supported previous data that the senescent RBC antigen is exposed via a dynamic process, wherein oscillation of a band 3 internal loop flipping to the cell surface, creates a conformational neoantigen that is the RBC senescent antigen. It has also recently been shown that the cytokine profile in patients with wAIHA favors production of inflammatory cytokines/chemokines that includes interleukin-8 which can activate neutrophils to increase the oxidative stress on circulating RBCs to induce novel antigens, as has been postulated to favour exposure of the senescent RBC antigen. SUMMARY This manuscript reviews new findings and hypotheses regarding wAIHA and proposes a novel mechanism active in most wAIHA patients that is due to an exacerbation of normal RBC senescence.
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Affiliation(s)
- Donald R Branch
- Departments of Medicine and Laboratory Medicine and Pathobiology, University of Toronto and the Canadian Blood Services, Centre for Innovation, Toronto, Ontario M5B 1W8, Canada
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2
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Cao H, Mathur A, Robertson C, Antonopoulos A, Henderson S, Girard LP, Wong JH, Davie A, Wright S, Brewin J, Rees DC, Dell A, Haslam SM, Vickers MA. Measurement of erythrocyte membrane mannoses to assess splenic function. Br J Haematol 2022; 198:155-164. [PMID: 35411940 PMCID: PMC9321840 DOI: 10.1111/bjh.18164] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Revised: 02/25/2022] [Accepted: 03/13/2022] [Indexed: 11/30/2022]
Abstract
Red blood cells (RBCs) lose plasma membrane in the spleen as they age, but the cells and molecules involved are yet to be identified. Sickle cell disease and infection by Plasmodium falciparum cause oxidative stress that induces aggregates of cross‐linked proteins with N‐linked high‐mannose glycans (HMGs). These glycans can be recognised by mannose‐binding lectins, including the mannose receptor (CD206), expressed on macrophages and specialised phagocytic endothelial cells in the spleen to mediate the extravascular haemolysis characteristic of these diseases. We postulated this system might also mediate removal of molecules and membrane in healthy individuals. Surface expression of HMGs on RBCs from patients who had previously undergone splenectomy was therefore assessed: high levels were indeed observable as large membrane aggregates. Glycomic analysis by mass spectrometry identified a mixture of Man5‐9GlcNAc2 structures. HMG levels correlated well with manual pit counts (r = 0.75–0.85). To assess further whether HMGs might act as a splenic reticuloendothelial function test, we measured levels on RBCs from patients with potential functional hyposplenism, some of whom exhibited high levels that may indicate risk of complications.
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Affiliation(s)
- Huan Cao
- School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, UK
| | - Abhinav Mathur
- Department of Haematology, Aberdeen Royal Infirmary, Aberdeen, UK
| | | | | | - Sadie Henderson
- School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, UK
| | | | - Jin Hien Wong
- School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, UK
| | - Adam Davie
- School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, UK
| | - Sonja Wright
- Department of Haematology, Aberdeen Royal Infirmary, Aberdeen, UK
| | - John Brewin
- Department of Haematology, King's College Hospital, London, UK
| | - David C Rees
- Department of Haematology, King's College Hospital, London, UK
| | - Anne Dell
- Department of Life Sciences, Imperial College London, London, UK
| | - Stuart M Haslam
- Department of Life Sciences, Imperial College London, London, UK
| | - Mark A Vickers
- School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, UK.,Department of Haematology, Aberdeen Royal Infirmary, Aberdeen, UK.,Scottish National Blood Transfusion Service, Aberdeen, UK
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3
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Cao H, Antonopoulos A, Henderson S, Wassall H, Brewin J, Masson A, Shepherd J, Konieczny G, Patel B, Williams ML, Davie A, Forrester MA, Hall L, Minter B, Tampakis D, Moss M, Lennon C, Pickford W, Erwig L, Robertson B, Dell A, Brown GD, Wilson HM, Rees DC, Haslam SM, Alexandra Rowe J, Barker RN, Vickers MA. Red blood cell mannoses as phagocytic ligands mediating both sickle cell anaemia and malaria resistance. Nat Commun 2021; 12:1792. [PMID: 33741926 PMCID: PMC7979802 DOI: 10.1038/s41467-021-21814-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Accepted: 02/08/2021] [Indexed: 02/06/2023] Open
Abstract
In both sickle cell disease and malaria, red blood cells (RBCs) are phagocytosed in the spleen, but receptor-ligand pairs mediating uptake have not been identified. Here, we report that patches of high mannose N-glycans (Man5-9GlcNAc2), expressed on diseased or oxidized RBC surfaces, bind the mannose receptor (CD206) on phagocytes to mediate clearance. We find that extravascular hemolysis in sickle cell disease correlates with high mannose glycan levels on RBCs. Furthermore, Plasmodium falciparum-infected RBCs expose surface mannose N-glycans, which occur at significantly higher levels on infected RBCs from sickle cell trait subjects compared to those lacking hemoglobin S. The glycans are associated with high molecular weight complexes and protease-resistant, lower molecular weight fragments containing spectrin. Recognition of surface N-linked high mannose glycans as a response to cellular stress is a molecular mechanism common to both the pathogenesis of sickle cell disease and resistance to severe malaria in sickle cell trait.
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Affiliation(s)
- Huan Cao
- grid.7107.10000 0004 1936 7291School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, UK
| | | | - Sadie Henderson
- grid.476695.f0000 0004 0495 4557Scottish National Blood Transfusion Service, Aberdeen, UK
| | - Heather Wassall
- grid.7107.10000 0004 1936 7291School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, UK
| | - John Brewin
- grid.46699.340000 0004 0391 9020Department of Haematology, King’s College Hospital, London, UK
| | - Alanna Masson
- grid.417581.e0000 0000 8678 4766Department of Haematology, Aberdeen Royal Infirmary, Aberdeen, UK
| | - Jenna Shepherd
- grid.7107.10000 0004 1936 7291School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, UK
| | - Gabriela Konieczny
- grid.7107.10000 0004 1936 7291School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, UK
| | - Bhinal Patel
- grid.7445.20000 0001 2113 8111Department of Life Sciences, Imperial College London, London, UK
| | - Maria-Louise Williams
- grid.7107.10000 0004 1936 7291School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, UK
| | - Adam Davie
- grid.7107.10000 0004 1936 7291School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, UK
| | - Megan A. Forrester
- grid.7107.10000 0004 1936 7291School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, UK
| | - Lindsay Hall
- grid.7107.10000 0004 1936 7291School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, UK
| | - Beverley Minter
- grid.7107.10000 0004 1936 7291School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, UK
| | - Dimitris Tampakis
- grid.13097.3c0000 0001 2322 6764Centre for Biological Engineering, School of Mechanical, Electrical and Manufacturing Engineering, Loughborough University and Division of Cancer Studies, King’s College London, London, UK
| | - Michael Moss
- grid.476695.f0000 0004 0495 4557Scottish National Blood Transfusion Service, Aberdeen, UK
| | - Charlotte Lennon
- grid.7107.10000 0004 1936 7291School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, UK
| | - Wendy Pickford
- grid.7107.10000 0004 1936 7291School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, UK
| | - Lars Erwig
- grid.7107.10000 0004 1936 7291School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, UK
| | - Beverley Robertson
- grid.7445.20000 0001 2113 8111Department of Life Sciences, Imperial College London, London, UK
| | - Anne Dell
- grid.46699.340000 0004 0391 9020Department of Haematology, King’s College Hospital, London, UK
| | - Gordon D. Brown
- grid.7107.10000 0004 1936 7291School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, UK ,grid.8391.30000 0004 1936 8024Medical Medical Research Council Centre for Medical Mycology at the University of Exeter, Exeter, UK
| | - Heather M. Wilson
- grid.7107.10000 0004 1936 7291School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, UK
| | - David C. Rees
- grid.46699.340000 0004 0391 9020Department of Haematology, King’s College Hospital, London, UK
| | - Stuart M. Haslam
- grid.7445.20000 0001 2113 8111Department of Life Sciences, Imperial College London, London, UK
| | - J. Alexandra Rowe
- grid.4305.20000 0004 1936 7988Centre for Immunity, Infection and Evolution, Institute of Immunology and Infection Research, University of Edinburgh, Edinburgh, UK
| | - Robert N. Barker
- grid.7107.10000 0004 1936 7291School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, UK
| | - Mark A. Vickers
- grid.7107.10000 0004 1936 7291School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, UK ,grid.476695.f0000 0004 0495 4557Scottish National Blood Transfusion Service, Aberdeen, UK ,grid.417581.e0000 0000 8678 4766Department of Haematology, Aberdeen Royal Infirmary, Aberdeen, UK
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Bloch EM, Branch HA, Sakac D, Leger RM, Branch DR. Differential red blood cell age fractionation and Band 3 phosphorylation distinguish two different subtypes of warm autoimmune hemolytic anemia. Transfusion 2020; 60:1856-1866. [PMID: 32750167 DOI: 10.1111/trf.15911] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Revised: 04/20/2020] [Accepted: 05/18/2020] [Indexed: 11/29/2022]
Abstract
Warm autoimmune hemolytic anemia (wAIHA) is a blood disorder characterized by the increased destruction of autologous red blood cells (RBCs) due to the presence of opsonizing pathogenic autoantibodies. Preliminary reports published more than three decades ago proposed the presence of two wAIHA subtypes: Type I, in which autoantibodies preferentially recognize the oldest, most dense RBCs; and Type II, characterized by autoantibodies that show no preference. STUDY DESIGN AND METHODS We evaluated patients having wAIHA for Type I and II subtype using discontinuous Percoll gradient age fractionation and direct antiglobulin test (DAT). We performed Western immunoblotting and mass spectrometry to show autoantibody specificity for Band 3. We investigated Band 3 tyrosine phosphorylation in different Percoll fractions to determine aging associated with oxidative stress. RESULTS We confirm the existence of two subtypes of wAIHA, Type I and Type II, and that autoantibodies recognize Band 3. Type I patients were characterized by five Percoll fractions, with a DAT showing IgG opsonization F1 < F5 and elevated Band 3 phosphorylation compared to healthy controls (HCs). In contrast, Type II wAIHA patients were characterized by three to four Percoll fractions, where the DAT IgG opsonization shows F1 ≥ F3/4 and Band 3 phosphorylation was absent or significantly decreased compared to HC. CONCLUSIONS Type I patients have increased Band 3 tyrosine phosphorylation that may represent accelerated aging of their RBCs resulting in exacerbation of a pathologic form of RBC senescence. Type II patients show decreased Band 3 tyrosine phosphorylation and lack the oldest, most dense RBCs suggesting premature RBC clearance and a more severe wAIHA.
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Affiliation(s)
- Evgenia M Bloch
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada.,Centre for Innovation, Canadian Blood Services, Toronto, Ontario, Canada
| | - Haley A Branch
- Centre for Innovation, Canadian Blood Services, Toronto, Ontario, Canada.,Department of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Darinka Sakac
- Centre for Innovation, Canadian Blood Services, Toronto, Ontario, Canada
| | - Regina M Leger
- American Red Cross, Southern California Region, Pomona, California, USA
| | - Donald R Branch
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada.,Centre for Innovation, Canadian Blood Services, Toronto, Ontario, Canada.,Department of Medicine, University of Toronto, Toronto, Ontario, Canada.,Toronto General Hospital Research Institute, University Health Network, Toronto, Ontario, Canada
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5
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Kawamoto S, Kamesaki T, Masutani R, Kitao A, Hatanaka K, Imakita M, Tamaki T, Takubo T. Ectopic expression of band 3 anion transport protein in colorectal cancer revealed in an autoimmune hemolytic anemia patient. Hum Pathol 2019; 83:193-198. [DOI: 10.1016/j.humpath.2018.07.020] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/21/2018] [Revised: 06/26/2018] [Accepted: 07/10/2018] [Indexed: 11/30/2022]
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Sys J, Provan D, Schauwvlieghe A, Vanderschueren S, Dierickx D. The role of splenectomy in autoimmune hematological disorders: Outdated or still worth considering? Blood Rev 2017; 31:159-172. [DOI: 10.1016/j.blre.2017.01.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2016] [Revised: 12/12/2016] [Accepted: 01/03/2017] [Indexed: 01/26/2023]
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Disturbed B-lymphocyte selection in autoimmune lymphoproliferative syndrome. Blood 2016; 127:2193-202. [PMID: 26907631 DOI: 10.1182/blood-2015-04-642488] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2015] [Accepted: 02/15/2016] [Indexed: 01/05/2023] Open
Abstract
Fas is a transmembrane receptor involved in the maintenance of tolerance and immune homeostasis. In murine models, it has been shown to be essential for deletion of autoreactive B cells in the germinal center. The role of Fas in human B-cell selection and in development of autoimmunity in patients carrying FAS mutations is unclear. We analyzed patients with either a somatic FAS mutation or a germline FAS mutation and somatic loss-of-heterozygosity, which allows comparing the fate of B cells with impaired vs normal Fas signaling within the same individual. Class-switched memory B cells showed: accumulation of FAS-mutated B cells; failure to enrich single V, D, J genes and single V-D, D-J gene combinations of the B-cell receptor variable region; increased frequency of variable regions with higher content of positively charged amino acids; and longer CDR3 and maintenance of polyreactive specificities. Importantly, Fas-deficient switched memory B cells showed increased rates of somatic hypermutation. Our data uncover a defect in B-cell selection in patients with FAS mutations, which has implications for the understanding of the pathogenesis of autoimmunity and lymphomagenesis of autoimmune lymphoproliferative syndrome.
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8
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Swann JW, Garden OA. Novel immunotherapies for immune-mediated haemolytic anaemia in dogs and people. Vet J 2016; 207:13-9. [DOI: 10.1016/j.tvjl.2015.10.022] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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9
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Lyse or not to lyse: Clinical significance of red blood cell autoantibodies. Blood Rev 2015; 29:369-76. [DOI: 10.1016/j.blre.2015.05.001] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2015] [Revised: 05/03/2015] [Accepted: 05/04/2015] [Indexed: 01/08/2023]
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10
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Bloch EM, Sakac D, Branch HA, Cserti-Gazdewich C, Pendergrast J, Pavenski K, Branch DR. Western immunoblotting as a new tool for investigating direct antiglobulin test-negative autoimmune hemolytic anemias. Transfusion 2015; 55:1529-37. [DOI: 10.1111/trf.13082] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2014] [Revised: 02/08/2015] [Accepted: 02/10/2015] [Indexed: 11/27/2022]
Affiliation(s)
- Evgenia M. Bloch
- Department of Laboratory Medicine and Pathobiology; University of Toronto
- Centre for Innovation; Canadian Blood Services
| | | | | | - Christine Cserti-Gazdewich
- Department of Laboratory Medicine and Pathobiology; University of Toronto
- Centre for Innovation; Canadian Blood Services
- Department of Medicine; University of Toronto
- Toronto General Hospital, University Health Network
| | - Jacob Pendergrast
- Department of Laboratory Medicine and Pathobiology; University of Toronto
- Department of Medicine; University of Toronto
- Toronto General Hospital, University Health Network
| | - Katerina Pavenski
- Department of Laboratory Medicine and Pathobiology; University of Toronto
- St. Michael's Hospital; Toronto Ontario Canada
| | - Donald R. Branch
- Department of Laboratory Medicine and Pathobiology; University of Toronto
- Centre for Innovation; Canadian Blood Services
- Department of Medicine; University of Toronto
- Toronto General Hospital, University Health Network
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11
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Dinkla S, Novotný VMJ, Joosten I, Bosman GJCGM. Storage-induced changes in erythrocyte membrane proteins promote recognition by autoantibodies. PLoS One 2012; 7:e42250. [PMID: 22879923 PMCID: PMC3411782 DOI: 10.1371/journal.pone.0042250] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2012] [Accepted: 07/05/2012] [Indexed: 12/19/2022] Open
Abstract
Physiological erythrocyte removal is associated with a selective increase in expression of neoantigens on erythrocytes and their vesicles, and subsequent autologous antibody binding and phagocytosis. Chronic erythrocyte transfusion often leads to immunization and the formation of alloantibodies and autoantibodies. We investigated whether erythrocyte storage leads to the increased expression of non-physiological antigens. Immunoprecipitations were performed with erythrocytes and vesicles from blood bank erythrocyte concentrates of increasing storage periods, using patient plasma containing erythrocyte autoantibodies. Immunoprecipitate composition was identified using proteomics. Patient plasma antibody binding increased with erythrocyte storage time, while the opposite was observed for healthy volunteer plasma, showing that pathology-associated antigenicity changes during erythrocyte storage. Several membrane proteins were identified as candidate antigens. The protein complexes that were precipitated by the patient antibodies in erythrocytes were different from the ones in the vesicles formed during erythrocyte storage, indicating that the storage-associated vesicles have a different immunization potential. Soluble immune mediators including complement factors were present in the patient plasma immunoprecipitates, but not in the allogeneic control immunoprecipitates. The results support the theory that disturbed erythrocyte aging during storage of erythrocyte concentrates contributes to transfusion-induced alloantibody and autoantibody formation.
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Affiliation(s)
- Sip Dinkla
- Department of Laboratory Medicine - Laboratory of Medical Immunology, Radboud University Medical Centre, Nijmegen Institute for Infection Inflammation and Immunity, Nijmegen, The Netherlands
| | - Věra M. J. Novotný
- Department of Hematology, Radboud University Medical Centre, Nijmegen, The Netherlands
| | - Irma Joosten
- Department of Laboratory Medicine - Laboratory of Medical Immunology, Radboud University Medical Centre, Nijmegen Institute for Infection Inflammation and Immunity, Nijmegen, The Netherlands
| | - Giel J. C. G. M. Bosman
- Department of Biochemistry, Radboud University Medical Centre, Nijmegen Centre for Molecular Life Sciences, Nijmegen, The Netherlands
- * E-mail:
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Hudson KE, Hendrickson JE, Cadwell CM, Iwakoshi NN, Zimring JC. Partial tolerance of autoreactive B and T cells to erythrocyte-specific self-antigens in mice. Haematologica 2012; 97:1836-44. [PMID: 22733018 DOI: 10.3324/haematol.2012.065144] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
BACKGROUND Breakdown of humoral tolerance to RBC antigens may lead to autoimmune hemolytic anemia, a severe and sometimes fatal disease. The underlying mechanisms behind the breakdown of humoral tolerance to RBC antigens are poorly understood. DESIGN AND METHODS In order to study the pathogenesis of autoimmune hemolytic anemia, we developed a murine model with RBC-specific expression of a model antigen carrying epitopes from hen egg lysozyme and ovalbumin. RESULTS Humoral tolerance was observed; this was not broken even by strong immunogenic stimulation (lysozyme or ovalbumin with adjuvant). Autoreactive CD4(+) T cells were detected by tetramer enrichment assays, but failed to activate or expand despite repeat stimulation, indicating a nonresponsive population rather than deletion. Adoptive transfer of autoreactive CD4(+) T cells (OT-II mice) led to autoantibody (anti-lysozyme) production by B cells in multiple anatomic compartments, including the bone marrow. CONCLUSIONS These data demonstrate that B cells autoreactive to RBC antigens survive in healthy mice with normal immune systems. Furthermore, autoreactive B cells are not centrally tolerized and are receptive to T-cell help. As the autoreactive T cells are present but non-responsive, these data indicate that factors that reverse T-cell non-responsiveness may be central to the pathogenesis of autoimmune hemolytic anemia.
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Affiliation(s)
- Krystalyn E Hudson
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, GA, USA
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13
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Hall AM, Zamzami OM, Whibley N, Hampsey DP, Haggart AM, Vickers MA, Barker RN. Production of the effector cytokine interleukin-17, rather than interferon-γ, is more strongly associated with autoimmune hemolytic anemia. Haematologica 2012; 97:1494-500. [PMID: 22419580 DOI: 10.3324/haematol.2011.060822] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
BACKGROUND Interleukin-17A is the signature cytokine of the Th17 subset and drives inflammatory pathology, but its relevance to autoantibody-mediated diseases is unclear. Th1 cells secreting interferon-γ have been implicated in autoimmune hemolytic anemia, so the aim was to determine which cytokine is more closely associated with disease severity. DESIGN AND METHODS Interferon-γ and interleukin-17A were measured in the sera of patients with autoimmune hemolytic anemia and healthy donors, and in peripheral blood mononuclear cell cultures stimulated with autologous red blood cells, or a panel of peptides spanning red blood cell autoantigen. RESULTS Serum interleukin-17A, but not interferon-γ, was significantly raised in patients with autoimmune hemolytic anemia (P<0.001), and correlated with the degree of anemia. Interleukin-17A was also more prominent in the responses of peripheral blood mononuclear cells from patients with autoimmune hemolytic anemia to red blood cells, and, again unlike interferon-γ, significantly associated with more severe anemia (P<0.005). There were no interleukin-17A responses to red blood cells by peripheral blood mononuclear cells from healthy donors. Specific autoantigenic peptides were identified that elicit patients' interleukin-17A responses. CONCLUSIONS Interleukin-17A makes a previously unrecognized contribution to the autoimmune response in autoimmune hemolytic anemia, challenging the model that the disease is driven primarily by Th1 cells. This raises the possibility that Th17, rather than Th1, cells should be the target for therapy.
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Affiliation(s)
- Andrew M Hall
- Section of Immunology & Infection, Division of Applied Medicine, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, UK.
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14
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Scatizzi JC, Haraldsson MK, Pollard KM, Theofilopoulos AN, Kono DH. The Lbw2 locus promotes autoimmune hemolytic anemia. THE JOURNAL OF IMMUNOLOGY 2012; 188:3307-14. [PMID: 22371393 DOI: 10.4049/jimmunol.1103561] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The lupus-prone New Zealand Black (NZB) strain uniquely develops a genetically imposed severe spontaneous autoimmune hemolytic anemia (AIHA) that is very similar to the corresponding human disease. Previous studies have mapped anti-erythrocyte Ab (AEA)-promoting NZB loci to several chromosomal locations, including chromosome 4; however, none of these have been analyzed with interval congenics. In this study, we used NZB.NZW-Lbw2 congenic (designated Lbw2 congenic) mice containing an introgressed fragment of New Zealand White (NZW) on chromosome 4 encompassing Lbw2, a locus previously linked to survival, glomerulonephritis, and splenomegaly, to investigate its role in AIHA. Lbw2 congenic mice exhibited marked reductions in AEAs and splenomegaly but not in anti-nuclear Abs. Furthermore, Lbw2 congenics had greater numbers of marginal zone B cells and reduced expansion of peritoneal cells, particularly the B-1a cell subset at early ages, but no reduction in B cell response to LPS. Analysis of a panel of subinterval congenic mice showed that the full effect of Lbw2 on AEA production was dependent on three subloci, with splenomegaly mapping to two of the subloci and expansions of peritoneal cell populations, including B-1a cells to one. These results directly demonstrated the presence of AEA-specific promoting genes on NZB chromosome 4, documented a marked influence of background genes on autoimmune phenotypes related to Lbw2, and further refined the locations of the underlying genetic variants. Delineation of the Lbw2 genes should yield new insights into both the pathogenesis of AIHA and the nature of epistatic interactions of lupus-modifying genetic variants.
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Affiliation(s)
- John C Scatizzi
- Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, CA 92037, USA
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15
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Barros MM, Blajchman MA, Bordin JO. Warm Autoimmune Hemolytic Anemia: Recent Progress in Understanding the Immunobiology and the Treatment. Transfus Med Rev 2010; 24:195-210. [DOI: 10.1016/j.tmrv.2010.03.002] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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16
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Galletti J, Cañones C, Morande P, Borge M, Oppezzo P, Geffner J, Bezares R, Gamberale R, Giordano M. Chronic lymphocytic leukemia cells bind and present the erythrocyte protein band 3: possible role as initiators of autoimmune hemolytic anemia. THE JOURNAL OF IMMUNOLOGY 2008; 181:3674-83. [PMID: 18714043 DOI: 10.4049/jimmunol.181.5.3674] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The mechanisms underlying the frequent association between chronic lymphocytic leukemia (CLL) and autoimmune hemolytic anemia are currently unclear. The erythrocyte protein band 3 (B3) is one of the most frequently targeted Ags in autoimmune hemolytic anemia. In this study, we show that CLL cells specifically recognize B3 through a still unidentified receptor. B3 interaction with CLL cells involves the recognition of its N-terminal domain and leads to its internalization. Interestingly, when binding of erythrocyte-derived vesicles as found physiologically in blood was assessed, we observed that CLL cells could only interact with inside-out vesicles, being this interaction strongly dependent on the recognition of the N-terminal portion of B3. We then examined T cell responses to B3 using circulating CLL cells as APCs. Resting B3-pulsed CLL cells were unable to induce T cell proliferation. However, when deficient costimulation was overcome by CD40 engagement, B3-pulsed CLL cells were capable of activating CD4(+) T cells in a HLA-DR-dependent fashion. Therefore, our work shows that CLL cells can specifically bind, capture, and present B3 to T cells when in an activated state, an ability that could allow the neoplastic clone to trigger the autoaggressive process against erythrocytes.
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Affiliation(s)
- Jeremías Galletti
- Department of Immunology, Institute for Hematologic Research, National Academy of Medicine, Buenos Aires, Argentina
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17
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Abstract
The diagnosis of autoimmune hemolytic anemia (AHA) requires evidence of shortened red blood cell (RBC) survival mediated by autoantibodies directed against autologous RBCs. About 80 percent of patients with AHA have warm-reactive antibodies of the IgG isotype; the remainder exhibit cold-reactive autoantibodies. Typical patients exhibit anemia, reticulocytosis, spherocytes and polychromasia on the blood film and a positive direct antiglobulin test (DAT). Increased indirect serum bilirubin, urinary urobilinogen and serum lactate dehydrogenase (LDH), and decreased serum haptoglobin are not required for the diagnosis, but are frequently present. Patients with AHA and no underlying associated disease are said to have primary or idiopathic AHA. AHA in patients with associated autoimmune disease and certain malignant or infectious diseases is classified as secondary. The etiology of AHA is unknown. Patients with symptomatic anemia require transfusion of RBCs. Prednisone and splenectomy may provide long term remission. Rituximab, intravenous immunoglobulin, immunosuppressive drugs and danazol have been effective in refractory cases and for patients who are poor candidates for surgery.
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Affiliation(s)
- Charles H Packman
- University of North Carolina School of Medicine, Chapel Hill, North Carolina, United States.
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18
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Hall AM, Ward FJ, Shen CR, Rowe C, Bowie L, Devine A, Urbaniak SJ, Elson CJ, Barker RN. Deletion of the dominant autoantigen in NZB mice with autoimmune hemolytic anemia: effects on autoantibody and T-helper responses. Blood 2007; 110:4511-7. [PMID: 17785581 DOI: 10.1182/blood-2007-06-094383] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The mechanisms underlying apparently spontaneous autoimmune diseases, such as autoimmune hemolytic anemia (AIHA) in New Zealand Black (NZB) mice, are unknown. Here, we determine the contribution of the dominant red blood cell (RBC) autoantigen, the anion exchanger protein Band 3, to the development of NZB autoimmune responses. The approach was to prevent Band 3 expression in NZB mice by disrupting the AE1 gene. AE1(-/-) NZB mice produced RBC autoantibodies at the same levels as the wild-type strain, but they differed in recognizing antigens that correspond to glycophorins, rather than Band 3. Splenic T-helper (Th) cells from wild-type NZB mice proliferated strongly against multiple Band 3 peptides, particularly the dominant epitope within aa861-874. This helper response was severely attenuated in AE1(-/-) animals, leaving only weak proliferation to peptide aa861-874. The results demonstrate that the defect in self-tolerance in NZB AIHA is directed to the RBC type, and is not specific for, or dependent on, Band 3. However, the predisposition to RBC autoimmunity may be focused onto Band 3 by weak Th cell cross-reactivity between the helper dominant epitope and an exogenous antigen. The redundancy of the major autoantigen illustrates the requirement for specific therapy to induce dominant forms of tolerance, such as T-cell regulation.
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Affiliation(s)
- Andrew M Hall
- Department of Medicine and Therapeutics, University of Aberdeen, Aberdeen, UK
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19
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Abstract
Autoimmune hemolytic anemia (AIHA) is diagnosed in the presence of anemia, usually macrocytic and of variable intensity, reticulocytosis, and a positive direct and/or indirect antiglobulin test, after ruling out other types of hemolytic anemia. A positive direct antiglobulin test alone is not sufficient to diagnose AIHA and may be positive in many patients without anemia or negative in some patients with AIHA. AIHA may be classified into two major categories according to the optimal temperature of antibody activity: warm-reacting autoantibodies (usually IgG) optimal around 37 degrees C and cold-reacting autoantibodies, optimal at 4 degrees C (usually IgM). This classification guides the selection of tests and treatment. AIHA is widely reported to be associated with a variety of other diseases, although these associations are often fortuitous. A minimal set of useful investigations is appropriate since AIHA may be secondary to viral infections, lymphoid malignancies, or autoimmune disorders such as lupus. Transfusion should remain rare in AHAI, but close contact with the transfusion service is necessary if it is to succeed. As for many autoimmune and/or systemic diseases, numerous types of treatment have been proposed but have not been validated in controlled multicenter studies. These are necessary to improve the management of these rare disorders.
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MESH Headings
- Adrenal Cortex Hormones/administration & dosage
- Adrenal Cortex Hormones/therapeutic use
- Adult
- Algorithms
- Anemia, Hemolytic, Autoimmune/diagnosis
- Anemia, Hemolytic, Autoimmune/drug therapy
- Anemia, Hemolytic, Autoimmune/etiology
- Anemia, Hemolytic, Autoimmune/immunology
- Anemia, Hemolytic, Autoimmune/therapy
- Antibodies, Monoclonal/administration & dosage
- Antibodies, Monoclonal/therapeutic use
- Antibodies, Monoclonal, Murine-Derived
- Autoantibodies/blood
- Blood Transfusion
- Child
- Child, Preschool
- Clinical Trials as Topic
- Coombs Test
- Danazol/therapeutic use
- Female
- Follow-Up Studies
- Forecasting
- Hemagglutination Tests
- Humans
- Immunoglobulins, Intravenous/therapeutic use
- Immunologic Factors/administration & dosage
- Immunologic Factors/therapeutic use
- Immunosuppressive Agents/administration & dosage
- Immunosuppressive Agents/therapeutic use
- Male
- Middle Aged
- Plasma Exchange
- Rituximab
- Splenectomy
- Time Factors
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Affiliation(s)
- Pierre Philippe
- Service de médecine interne, Hôtel-Dieu, CHU de Clermont-Ferrand, Clermont-Ferrand, France.
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20
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Barker RN, Vickers MA, Ward FJ. Controlling autoimmunity—Lessons from the study of red blood cells as model antigens. Immunol Lett 2007; 108:20-6. [PMID: 17134764 DOI: 10.1016/j.imlet.2006.10.005] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2006] [Revised: 10/13/2006] [Accepted: 10/20/2006] [Indexed: 11/29/2022]
Abstract
The characterization of human and animal red blood cell (RBC) autoantigens in autoimmune hemolytic anemia (AIHA) has provided an opportunity study the control of specific autoimmune responses of unequivocal pathogenic relevance. The results reveal that censorship of the autoimmune helper T (Th) cell repertoire by deletion and anergy is very incomplete in healthy individuals, even for widely distributed, abundant self-antigens on RBC. There is strong evidence that autoaggression by surviving Th cells is normally held in check by other mechanisms, including failure to display the epitopes that they recognize, and active immunoregulation. AIHA is one of the first human autoimmune diseases in which regulatory T (Tr) cells that are specific for the major autoantigens have been identified. These Tr cells recognize the dominant naturally processed epitopes, and recent studies suggest that disease develops when other determinants, to which such tolerance is less secure, and which are normally inefficiently presented, are displayed at higher levels. Together, the results raise the possibility that therapy for diseases such as AIHA could be based on switching the balance of the response back towards regulation, in particular by the administration of the dominant peptides recognized by specific Tr cells.
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Affiliation(s)
- Robert N Barker
- Department Medicine and Therapeutics, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeeen AB25 2ZD, UK.
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21
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Stahl D. Warm Autoimmune Hemolytic Anemia: A Clinical Model to Study Mechanisms of Immunoregulation*. Transfus Med Hemother 2006. [DOI: 10.1159/000091108] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
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22
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Stahl D, Sibrowski W. Warm autoimmune hemolytic anemia is an IgM–IgG immune complex disease. J Autoimmun 2005; 25:272-82. [PMID: 16242913 DOI: 10.1016/j.jaut.2005.08.003] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2005] [Revised: 07/11/2005] [Accepted: 08/01/2005] [Indexed: 10/25/2022]
Abstract
Warm autoimmune hemolytic anemia (WAIHA) is characterized by polyclonal IgG autoantibodies binding to red blood cells (RBC). The characterization of the autoantigen in WAIHA has not yet led to definitive results, and the etiology of RBC autoantibodies remains unclear. An altered control of self-reactive IgG by autologous IgM has been proposed as the underlying mechanism of disease in WAIHA, suggesting that IgM-IgG immune complexes contribute to the pathophysiology of the disease. In the present study, we purified and characterized IgM from plasma of WAIHA patients and from healthy controls using FPLC-based protocols and optical biosensor technology, and investigated IgG present within the IgM fractions. We provide evidence that IgM-IgG immune complexes in plasma and associated with the RBC membrane are the characteristic feature of WAIHA, independent of the etiology of the disease. IgM-IgG immune complexes of WAIHA patients differ from IgM-IgG immune complexes of healthy individuals with regard to quantity and to structural composition. The data suggest that self-immunoglobulin is the original autoantigen underlying WAIHA. The molecular characterization of IgM-IgG immune complexes may define new targets for therapeutic intervention in WAIHA.
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Affiliation(s)
- D Stahl
- Institute for Transfusion Medicine, University of Münster, Domagkstrasse 11, D-48149 Münster, Germany.
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23
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Hall AM, Vickers MA, McLeod E, Barker RN. Rh autoantigen presentation to helper T cells in chronic lymphocytic leukemia by malignant B cells. Blood 2005; 105:2007-15. [PMID: 15284121 DOI: 10.1182/blood-2003-10-3563] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
AbstractChronic lymphocytic leukemia (CLL) is frequently associated with autoimmune diseases directed against constituents of the blood, including hemolytic anemia (AIHA). We hypothesized that CLL cells predispose to hematologic autoimmunity by acting as aberrant antigen-presenting cells (APCs). Initially, it was confirmed that all studied patients with AIHA secondary to CLL harbored activated helper T (TH) cells specific for epitopes on the dominant red blood cell (RBC) autoantigens in primary AIHA, the Rh proteins. Rh-specific TH cells were also detected in a number of patients with CLL who, although they did not have AIHA, had low levels of anti-RBC antibody in their sera. Fractionation of putative APC populations from the peripheral blood of patients by negative selection showed that CD5+ CLL cells are the most effective cell type in processing and presenting purified Rh protein to autoreactive TH cells. This ability was confirmed using positively selected CD5+ CLL cells. Thus, our study provides the first evidence for malignant cells driving an autoimmune response by acting as aberrant APCs.
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MESH Headings
- Adolescent
- Adult
- Aged
- Aged, 80 and over
- Antibody Specificity
- Antigen Presentation
- Autoantibodies/blood
- Autoantigens
- Autoimmune Diseases/etiology
- B-Lymphocytes/immunology
- B-Lymphocytes/pathology
- CD5 Antigens/analysis
- Female
- Humans
- Leukemia, Lymphocytic, Chronic, B-Cell/blood
- Leukemia, Lymphocytic, Chronic, B-Cell/complications
- Leukemia, Lymphocytic, Chronic, B-Cell/immunology
- Male
- Middle Aged
- Rh-Hr Blood-Group System/immunology
- T-Cell Antigen Receptor Specificity/immunology
- T-Lymphocytes, Helper-Inducer/immunology
- T-Lymphocytes, Helper-Inducer/pathology
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Affiliation(s)
- Andrew M Hall
- Department of Medicine and Therapeutics, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, United Kingdom
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24
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Sherer Y, Gorstein A, Fritzler MJ, Shoenfeld Y. Autoantibody explosion in systemic lupus erythematosus: more than 100 different antibodies found in SLE patients. Semin Arthritis Rheum 2005; 34:501-37. [PMID: 15505768 DOI: 10.1016/j.semarthrit.2004.07.002] [Citation(s) in RCA: 422] [Impact Index Per Article: 22.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
OBJECTIVE Description of the various autoantibodies that can be detected in patients with systemic lupus erythematosus (SLE). METHODS A literature review, using the terms "autoantibody" and "systemic lupus erythematosus", was conducted to search for articles on autoantibodies in SLE, their target antigens, association with disease activity, or other clinical associations. RESULTS One hundred sixteen autoantibodies were described in SLE patients. These include autoantibodies that target nuclear antigens, cytoplasmic antigens, cell membrane antigens, phospholipid-associated antigens, blood cells, endothelial cells, and nervous system antigens, plasma proteins, matrix proteins, and miscellaneous antigens. The target of autoantibody, the autoantigen properties, autoantibody frequencies in SLE, as well as clinical associations, and correlation with disease activity are described for all 116 autoantibodies. CONCLUSIONS SLE is the autoimmune disease with the largest number of detectable autoantibodies. Their production could be antigen-driven, the result of polyclonal B cell activation, impaired apoptotic pathways, or the outcome of idiotypic network dysregulation.
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Affiliation(s)
- Yaniv Sherer
- Department of Medicine B and Center for Autoimmune Disease, Sheba Medical Center, Tel-Hashomer 52621, Israel
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25
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26
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Hall AM, Ward FJ, Vickers MA, Stott LM, Urbaniak SJ, Barker RN. Interleukin-10-mediated regulatory T-cell responses to epitopes on a human red blood cell autoantigen. Blood 2002; 100:4529-36. [PMID: 12393426 DOI: 10.1182/blood-2002-05-1383] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Regulatory T cells have been shown to control animal models of immune-mediated pathology by inhibitory cytokine production, but little is known about such cells in human disease. Here we characterize regulatory T-cell responses specific for a human red blood cell autoantigen in patients with warm-type autoimmune hemolytic anemia. Peripheral blood mononuclear cells from patients with autoimmune hemolytic anemia were found either to proliferate and produce interferon-gamma or to secrete the regulatory cytokine interleukin 10 when stimulated in vitro with a major red blood cell autoantigen, the RhD protein. Flow cytometric analysis confirmed that the majority of the responding cells were of the CD4(+) phenotype. Serial results from individual patients demonstrated that this bias toward proliferative or interleukin-10 responses was unstable over time and could reverse in subsequent samples. Epitope mapping studies identified peptides from the sequence of the autoantigen that preferentially induced interleukin-10 production, rather than proliferation, and demonstrated that many contain naturally processed epitopes. Responses to such peptides suppressed T-cell proliferation against the RhD protein, an inhibition that was mediated largely by interleukin 10 and dependent on cytotonic T lymphocyte-associated antigen (CTLA-4) costimulation. Antigenic peptides with the ability to stimulate specific regulatory cells may represent a new class of therapeutic agents for immune-mediated disease.
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Affiliation(s)
- Andrew M Hall
- Department of Medicine and Therapeutics, Institute of Medical Sciences, University of Aberdeen Foresterhill, Aberdeen, United Kingdom
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27
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Barker RN, Shen CR, Elson CJ. T-cell specificity in murine autoimmune haemolytic anaemia induced by rat red blood cells. Clin Exp Immunol 2002; 129:208-13. [PMID: 12165075 PMCID: PMC1906435 DOI: 10.1046/j.1365-2249.2002.01917.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/01/2002] [Indexed: 11/20/2022] Open
Abstract
Autoimmune haemolytic anaemia (AIHA) can be induced in mice by repeated injections with rat red blood cells (RBC). Here we describe the identification of rat and murine RBC antigens recognized by T-cells from mice with this disease. Splenic T-cells from mice with AIHA proliferated in response to multiple murine RBC membrane components, each of which is recognized by rat RBC induced autoantibodies. Thus, there were responses to murine autoantigen fractions that correspond in apparent molecular mass with the anion channel Band 3, with spectrin from the membrane skeleton and with the high and low molecular mass glycophorins, and the equivalent fractions from rat RBC also stimulated proliferation by T-cells. It was confirmed that purified Band 3 from murine and rat RBC also elicited responses. In contrast with the results in AIHA, T-cells from healthy control mice failed to respond to the antigens from either species, with the exception of proliferation induced by murine spectrin in one experiment and weak responses elicited by rat Band 3. It is suggested that T-cells activated by multiple cross-reactions between rat and murine RBC proteins, and by epitope spreading, are necessary to drive autoantibody production in this model of AIHA.
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Affiliation(s)
- R N Barker
- Department of Medicine and Therapeutics, University of Aberdeen, UK.
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28
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Iwamoto S, Kamesaki T, Oyamada T, Okuda H, Kumada M, Omi T, Takahashi J, Tani Y, Omine M, Kajii E. Reactivity of autoantibodies of autoimmune hemolytic anemia with recombinant rhesus blood group antigens or anion transporter band3. Am J Hematol 2001; 68:106-14. [PMID: 11559950 DOI: 10.1002/ajh.1161] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The specificity of autoantibodies in autoimmune hemolytic anemia (AIHA) has been studied using the serological procedure and immunoprecipitation technique with rare phenotype red cells. We attempted to analyze specificity using recombinant rhesus (Rh) blood group and band3 antigens expressed on erythroleukemic cell lines, KU812E. The autoantibody eluates were isolated by the acid elution procedure from the red cells of 20 AIHA patients. The recombinant Rh antigens, RhD, cE, ce, CE, and chimera antigens CE-D and D-CE, were obtained by retroviral cDNA transduction into KU812E cells, and the cell line expressing the antigens was cloned. Band3 cDNA was also obtained and introduced into KU812E and cloned KU812 expressing RhcE. The reactivities of AIHA eluates with recombinant Rh and band3 antigens were studied by flow cytometry. Fifteen eluates reacted with at least one of the RhcE, ce, or CE antigens, and four eluates reacted with RhD. Seven eluates with strong Rh specificity were studied further using chimera antigen. Five eluates showed reduced or lost reactivity, although two eluates reacted identically with the chimera antigens as wild type. These results indicated that conformational epitopes constituted by RhD or CE specific exofacial peptide loops are important for autoantibodies in most cases. Seven eluates reacted with band3, five exclusively. The coexpression study of RhcE and band3 did not enhance the expression of either antigen nor the reactivity with patient eluates, indicating that association of Rh and band3 was not involved in the appearance of autoantigen.
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MESH Headings
- Anemia, Hemolytic, Autoimmune/blood
- Anemia, Hemolytic, Autoimmune/immunology
- Anion Exchange Protein 1, Erythrocyte/immunology
- Anion Exchange Protein 1, Erythrocyte/metabolism
- Antibodies, Monoclonal/immunology
- Antibodies, Monoclonal/metabolism
- Antibody Specificity
- Antigen-Antibody Complex/analysis
- Autoantibodies/blood
- Autoantibodies/immunology
- Autoantibodies/isolation & purification
- Epitopes
- Erythrocytes/chemistry
- Erythrocytes/immunology
- Flow Cytometry
- Humans
- Recombinant Fusion Proteins/immunology
- Recombinant Fusion Proteins/metabolism
- Recombinant Proteins/immunology
- Rh-Hr Blood-Group System/immunology
- Transduction, Genetic
- Tumor Cells, Cultured
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Affiliation(s)
- S Iwamoto
- Department of Legal Medicine and Human Genetics, Jichi Medical School, Tochigi, Japan.
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29
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Abstract
The production of pathogenic autoantibodies in organ-specific autoimmune diseases is largely T cell dependent. For many of these diseases, the precise specificities and cytokine profiles of the T cells that respond to the corresponding autoantigens have now been identified. This knowledge has been exploited to treat some models of antibody-mediated autoimmunity using peptides corresponding to the dominant helper epitopes, giving impetus to the development of a similar approach in the equivalent human diseases.
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Affiliation(s)
- C J Elson
- Department of Pathology and Microbiology, School of Medical Sciences, University of Bristol, Bristol BS8 1TD, UK.
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30
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Abstract
Autoimmune haemolytic anaemia (AIHA) is the most common clinical manifestation of autoimmunity in the dog and generally presents as a profound, regenerative, Coombs' positive anaemia of acute or chronic onset. The disease pathogenesis involves formation of erythrocyte-specific autoantibodies of the IgG and IgM class that may fix complement resulting in intra- or extravascular haemolysis. Western blotting and immunoprecipitation studies using autoantibody eluted from the erythrocytes of dogs with AIHA have demonstrated specificity for erythrocyte glycophorins and the membrane anion-exchange molecule (band 3). Autoantibodies specific for the cytoskeletal molecule spectrin have been identified in serum by ELISA. The specificity of autoreactive T-cells has been examined in vitro using bulk cultures stimulated with a panel of autoantigens including intact erythrocyte membranes, purified glycophorin and spectrin fractions and a panel of overlapping 15-mer glycophorin peptides. Control responses to ConA and recall (vaccine antigens) and non-recall (KLH) antigens were measured in the same system. PBMC obtained from dogs that had recovered from AIHA consistently proliferated in response to erythrocyte membranes, with occasional responses to spectrin or glycophorin. PBMC from sone clinically normal dogs also responded to erythrocyte membranes. PBMC obtained from dogs closely related to AIHA cases gave the most consistent responses, including proliferation when stimulated by the glycophorin peptides. These data suggest that normal dogs harbour erythrocyte autoreactive lymphocytes, and that these cells may be primed in dogs recovered from AIHA or having genetic susceptibility to the disease.
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Affiliation(s)
- M J Day
- Department of Pathology and Microbiology, University of Bristol, UK.
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31
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Abstract
Abstract
We have shown previously that the Rhesus (Rh) polypeptides are the commonest targets for pathogenic anti-red blood cell (RBC) autoantibodies in patients with autoimmune hemolytic anemia (AIHA). The aim of the current work was to determine whether activated T cells from such patients also mount recall responses to epitopes on these proteins. Two panels of overlapping 15-mer peptides, corresponding to the sequences of the 30-kD Rh proteins associated with expression of the D and Cc/Ee blood group antigens, were synthesized and screened for the ability to stimulate the in vitro proliferation of mononuclear cells from the peripheral blood or spleen of nine AIHA cases. Culture conditions were chosen that favor recall proliferation by previously activated T cells, rather than primary responses. In seven of the patients, including all four cases with autoantibody to the Rh proteins, two or more peptides elicited proliferation, but cells from eight of nine patients with other anemias and seven of nine healthy donors failed to respond to the panels. Multiple peptides were also stimulatory in two positive control donors who had been alloimmunized with Rh D-positive RBCs. Six different profiles of peptides elicited responses in the AIHA patients, and this variation may reflect the different HLA types in the group. Stimulatory peptides were identified throughout domains shared between, or specific to, each of the related 30-kD Rh proteins, but T cells that responded to nonconserved regions did not cross-react with the alternative sequences. Anti-major histocompatibility complex class II antibodies blocked the responses and depletion experiments confirmed that the proliferating mononuclear cells were T cells. Notably, splenic T cells that proliferated against multiple Rh peptides also responded to intact RBCs. We propose that pathogenic autoantibody production in many cases of AIHA is driven by the activation of T-helper cells specific for previously cryptic epitopes on the Rh proteins.
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32
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Abstract
We have shown previously that the Rhesus (Rh) polypeptides are the commonest targets for pathogenic anti-red blood cell (RBC) autoantibodies in patients with autoimmune hemolytic anemia (AIHA). The aim of the current work was to determine whether activated T cells from such patients also mount recall responses to epitopes on these proteins. Two panels of overlapping 15-mer peptides, corresponding to the sequences of the 30-kD Rh proteins associated with expression of the D and Cc/Ee blood group antigens, were synthesized and screened for the ability to stimulate the in vitro proliferation of mononuclear cells from the peripheral blood or spleen of nine AIHA cases. Culture conditions were chosen that favor recall proliferation by previously activated T cells, rather than primary responses. In seven of the patients, including all four cases with autoantibody to the Rh proteins, two or more peptides elicited proliferation, but cells from eight of nine patients with other anemias and seven of nine healthy donors failed to respond to the panels. Multiple peptides were also stimulatory in two positive control donors who had been alloimmunized with Rh D-positive RBCs. Six different profiles of peptides elicited responses in the AIHA patients, and this variation may reflect the different HLA types in the group. Stimulatory peptides were identified throughout domains shared between, or specific to, each of the related 30-kD Rh proteins, but T cells that responded to nonconserved regions did not cross-react with the alternative sequences. Anti-major histocompatibility complex class II antibodies blocked the responses and depletion experiments confirmed that the proliferating mononuclear cells were T cells. Notably, splenic T cells that proliferated against multiple Rh peptides also responded to intact RBCs. We propose that pathogenic autoantibody production in many cases of AIHA is driven by the activation of T-helper cells specific for previously cryptic epitopes on the Rh proteins.
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33
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Shen CR, Mazza G, Perry FE, Beech JT, Thompson SJ, Corato A, Newton S, Barker RN, Elson CJ. T-helper 1 dominated responses to erythrocyte Band 3 in NZB mice. Immunology 1996; 89:195-9. [PMID: 8943714 PMCID: PMC1456485 DOI: 10.1046/j.1365-2567.1996.d01-731.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Band 3, the red blood cell (RBC) anion channel protein, is the target autoantigen for the pathogenic RBC autoantibodies and T-helper (Th) cells in New Zealand Black (NZB) mice with autoimmune haemolytic anaemia (AIHA). To determine the subpopulation of these Th cells, they were stimulated with Band 3 and the profile of the cytokines elaborated by the responding cells was measured. NZB T cells stimulated with Band 3 produced high levels of the Th1 cytokine, interferon-gamma (IFN-gamma), but little or no interleukin-4 (IL-4), IL-5 or IL-10. Similar patterns were produced by NZB T cells responding to a spectrin preparation from the RBC membrane skeleton, or to mycobacterial heat-shock protein (hsp) 65 following immunization of mice with hsp 65 in incomplete adjuvant. By contrast, T cells from CBA mice similarly immunized with hsp 65 produced high levels of IL-4 and IL-5 in response to hsp 65. Examination of the isotype of the RBC-bound immunoglobulins in NZB mice revealed that immunoglobulin G2a (IgG2a) autoantibodies were the first to be detected in most mice and that later in the disease, IgG3 autoantibodies were often prominent. It is concluded that, contrary to expectation, the development of RBC autoantibodies in NZB mice is associated with Th1 cytokine-dominated responses.
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Affiliation(s)
- C R Shen
- Department of Pathology and Microbiology, University of Bristol, UK
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34
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Therapie mit Erythrozyten. TRANSFUSIONSMEDIZIN 1996. [DOI: 10.1007/978-3-662-10599-3_19] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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35
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Perry FE, Barker RN, Mazza G, Day MJ, Wells AD, Shen CR, Schofield AE, Elson CJ. Autoreactive T cell specificity in autoimmune hemolytic anemia of the NZB mouse. Eur J Immunol 1996; 26:136-41. [PMID: 8566056 DOI: 10.1002/eji.1830260121] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Splenic T cells from Coombs'-positive New Zealand Black (NZB) mice proliferated consistently in vitro in response to the integral red blood cell (RBC) membrane protein Band 3, the antigen previously shown to be the target for the pathogenic RBC autoantibodies. The responding cells predominantly express CD4 and the proliferative response is blocked by antibodies to the NZB major histocompatibility complex class II but not by antibodies to an irrelevant H-2 haplotype. NZB splenic T cells also proliferated in response to the internal membrane skeleton protein spectrin. By contrast, T cells from BALB/c and DBA2 mice, which bear the same H-2 haplotype as NZB mice, but which do not develop autoimmune hemolytic anemia (AIHA), fail to respond to Band 3. It is considered that these results support the hypothesis that Band 3-reactive T cells provide help for the production of pathogenic anti-Band 3 autoantibodies in NZB mice. T cells from Coombs'-negative NZB mice as young as 3 weeks old proliferated in response to Band 3; moreover, the RBC from Coombs'-negative mice bore elevated levels of autoantibody as judged by a sensitive direct enzyme-linked anti-globulin test. Thus, the pathology of AIHA develops at a much earlier age than was thought previously.
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Affiliation(s)
- F E Perry
- Department of Pathology and Microbiology, University of Bristol, GB
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36
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Barker RN, Elson CJ. Red blood cell glycophorins as B and T-cell antigens in canine autoimmune haemolytic anaemia. Vet Immunol Immunopathol 1995; 47:225-38. [PMID: 8571543 DOI: 10.1016/0165-2427(94)05407-j] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Pathogenic autoantibodies from two dogs with autoimmune haemolytic anaemia (AIHA) were shown to react with glycophorin from the canine red blood cell (RBC) membrane. Autoantibodies in both cases bound to purified glycophorin in enzyme-linked immunosorbent assays (ELISAs), and the major autoantigen immunoprecipitated by the antibodies corresponded in apparent molecular mass with glycophorin. Furthermore, neuraminidase treatment of the precipitated antigen, or of canine glycophorin, resulted in identical changes in apparent molecular mass in sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE). Such removal of sialic acid from glycophorins was demonstrated to cause shifts in SDS-PAGE migration that are unique among RBC membrane proteins. In two further cases of AIHA, where autoantibodies did not immunoprecipitate the glycophorin pattern, ELISAs revealed that RBC-reactive IgG was present in serum and RBC elutes, but that these antibodies failed to bind to canine glycophorin. Thus, we consider that autoantibodies specific for glycophorin are present in some, but not all, dogs with AIHA. T-cells from a case of AIHA proliferated in vitro in response to autologous RBC, or to multiple RBC membrane components fractionated by SDS-PAGE. Three fractions, corresponding to major glycophorins, to the RBC anion channel band 3, and to spectrin from the membrane skeleton, were stimulatory. In contrast, T-cells from healthy dogs failed to respond to RBC, or to any blot fractions with the exception, in one animal, of the fraction bearing spectrin. It is suggested that activation of autoreactive T-cells with multiple specificities may be necessary to provide sufficient help for pathogenic autoantibody production.
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Affiliation(s)
- R N Barker
- Department of Pathology and Microbiology, Medical School, University of Bristol, UK
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37
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De Angelis V, Biasinutto C, Pradella P, Errante D. Mixed-type auto-immune haemolytic anaemia in a patient with HIV infection. Vox Sang 1995; 68:191-4. [PMID: 7625078 DOI: 10.1111/j.1423-0410.1995.tb03926.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
A young HIV-infected patient presented with a severe auto-immune haemolytic anaemia with both warm and cold auto-antibodies, an infrequent category of anti-erythrocyte auto-immunity. Serological findings were compatible with the presence of a low-titre, high-thermal-amplitude anti-I cold-reacting antibody and a pan-reactive warm-reactive auto-antibody. Immunochemical characterisation of the warm antibody failed to identify any membrane protein acting as auto-antigen. This is, to our knowledge, the first reported case of mixed-type auto-immune haemolytic anaemia in a patient with HIV infection. Overt haemolysis is a very rare complication in HIV-infected patients, despite the high prevalence of a positive direct antiglobulin test reported in these patients. This suggests that HIV infection is a condition in which anti-erythrocyte auto-immunity is a serological finding without haemolytic effects in the large majority of cases.
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Affiliation(s)
- V De Angelis
- Servizio Immunotrasfusionale e Analisi Cliniche, IRCCS Centro di Riferimento Oncologico, Aviano, Italia
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38
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De Angelis V, Pradella P, Biasinutto C, Steffan A, Cozzi MR. Immunochemical studies on red cell auto antigens: use and limits of immunoprecipitation from biotinylated erythrocyte membrane. Autoimmunity 1995; 21:263-8. [PMID: 8852517 DOI: 10.3109/08916939509001945] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Erythrocyte surface was labelled by means of biotin; immunoprecipitation technique was then used to localise antigens recognised on red cell membrane proteins by: a) autoantibodies from 13 patients with antierythrocyte autoimmunity; b) commercially available anti-D and anti-k (Cellano) antierythrocyte alloantibodies. Results with alloantibodies are comparable to those obtained using radiochemical probes. Immunoprecipitations with autoantibody containing eluates showed reactivity at different molecular weights (the most common at 34-50 kD, others at 100 and 45 kD and a newly described one at 80 kD), thus confirming that many membrane proteins may act as target antigens for erythrocyte autoimmunity. We found a higher percentage of reactive immunoprecipitates than previously reported using the same labelling method. However, critical conditions to allow valuable results seem to be a threshold amount of autoantibody to precipitate any recognisable band and the sensitivity of the detection method. Hence methodological variables must be taken into consideration before concluding that "non protein" antigens trigger the autoimmune process.
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Affiliation(s)
- V De Angelis
- Servizio Immunotrasfusionale e Analisi Cliniche, IRCCS Centro di Riferimento Oncologico, Aviano, Italy
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39
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Barker RN, Elson CJ. Multiple self epitopes on the Rhesus polypeptides stimulate immunologically ignorant human T cells in vitro. Eur J Immunol 1994; 24:1578-82. [PMID: 7517875 DOI: 10.1002/eji.1830240719] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The extent of autoreactive T cell repertoire in the normal individual has previously been unclear. Here we demonstrate that T cells from healthy humans can be stimulated by multiple epitopes on a self protein to give primary proliferative responses in vitro. Synthetic 15-mer peptides, corresponding to the sequence of a human red blood cell Rhesus polypeptide, were tested for the ability to stimulate normal T cells. Multiple peptides were found to provoke responses reproducibly, and the proliferation could be blocked consistently by antibodies to HLA-DR, but not -DP or -DQ. T cells from each donor proliferated in response to different patterns of peptides, but this variation in pattern was less marked in individuals with the same HLA-DR type. The responses were comparable in kinetics to those elicited by the non-recall foreign antigen keyhole limpet hemocyanin, and the responding cells are most commonly derived from the CD45RA+ subpopulation, indicating that they had not been activated in vivo. It is considered that T cells are "immunologically ignorant" of many self peptides, presumably because they correspond to cryptic epitopes that are not normally presented in vivo.
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Affiliation(s)
- R N Barker
- Department of Pathology and Microbiology, University of Bristol, GB
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Eyers S, Ridgwell K, Mawby W, Tanner M. Topology and organization of human Rh (rhesus) blood group-related polypeptides. J Biol Chem 1994. [DOI: 10.1016/s0021-9258(17)37388-x] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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Guzmán J, Cabral AR, Cabiedes J, Pita-Ramirez L, Alarcón-Segovia D. Antiphospholipid antibodies in patients with idiopathic autoimmune haemolytic anemia. Autoimmunity 1994; 18:51-6. [PMID: 7999955 DOI: 10.3109/08916939409014679] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Isolated cases of anti-phospholipid antibody (aPL)-associated idiopathic autoimmune haemolytic anemia (IAHA) have been recently described. To assess the significances of this association, we studied by ELISA the presence of aPL in sera from 18 patients with IAHA and 14 patients with non-autoimmune haemolysis (NON-AH). Four IAHA cases and none of the NON-AH controls showed IgM anticardiolipin antibodies (aCL) that crossreacted extensively with zwitterionic as well as with other anionic phospholipids. IgG aCL were detected in 6 patients with IAHA and in 1 patient with NON-AH; there was little cross-reactivity with other phospholipids. Our results suggest that antiphospholipid antibodies are present in a substantial number of patients with IAHA. This humoral response does not seem to be secondary to the haemolysis proper. The potential pathogenic significance of this finding is discussed.
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Affiliation(s)
- J Guzmán
- Department of Immunology, Instituto Nacional de la Nutrición Salvador Zubirán, Tlalpan, México, D.F
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42
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Detection of red cell sensitisation by antibody and complement: Current practice and future perspectives. ACTA ACUST UNITED AC 1993. [DOI: 10.1007/bf02341967] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Barker RN, de Sá Oliveira GG, Elson CJ, Lydyard PM. Pathogenic autoantibodies in the NZB mouse are specific for erythrocyte band 3 protein. Eur J Immunol 1993; 23:1723-6. [PMID: 8325343 DOI: 10.1002/eji.1830230750] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
NZB mice spontaneously develop autoimmune hemolytic anemia (AIHA). The red blood cell (RBC) autoantigen bound by pathogenic IgG autoantibodies, previously designated "X", was identified by immunoprecipitation. Autoantibody eluted from the RBC of AIHA-positive NZB mice precipitated a 105-kDa antigen that was identical in apparent molecular mass to Band 3, the RBC anion channel protein. Furthermore, the immunoblotted antigen also reacted specifically with BRIC 132, a monoclonal antibody against Band 3. The results, therefore, demonstrate that Band 3 bears autoantigenic epitopes that are important in the pathogenesis of AIHA in the NZB mouse.
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Affiliation(s)
- R N Barker
- Department of Pathology and Microbiology, University of Bristol, London
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MESH Headings
- Adolescent
- Anemia, Hemolytic, Autoimmune/classification
- Anemia, Hemolytic, Autoimmune/epidemiology
- Anemia, Hemolytic, Autoimmune/immunology
- Anemia, Hemolytic, Autoimmune/pathology
- Antibody Formation
- Child
- Child, Preschool
- Complement System Proteins/immunology
- Erythrocytes/immunology
- Erythrocytes/pathology
- Humans
- Incidence
- Infant
- Infant, Newborn
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Affiliation(s)
- R J Sokol
- Regional Blood Transfusion Centre, Sheffield
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