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Wang Y, Meng FL, Yeap LS. DNA flexibility can shape the preferential hypermutation of antibody genes. Trends Immunol 2024; 45:167-176. [PMID: 38402044 DOI: 10.1016/j.it.2024.01.005] [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: 12/28/2023] [Revised: 01/28/2024] [Accepted: 01/29/2024] [Indexed: 02/26/2024]
Abstract
Antibody-coding genes accumulate somatic mutations to achieve antibody affinity maturation. Genetic dissection using various mouse models has shown that intrinsic hypermutations occur preferentially and are predisposed in the DNA region encoding antigen-contacting residues. The molecular basis of nonrandom/preferential mutations is a long-sought question in the field. Here, we summarize recent findings on how single-strand (ss)DNA flexibility facilitates activation-induced cytidine deaminase (AID) activity and fine-tunes the mutation rates at a mesoscale within the antibody variable domain exon. We propose that antibody coding sequences are selected based on mutability during the evolution of adaptive immunity and that DNA mechanics play a noncoding role in the genome. The mechanics code may also determine other cellular DNA metabolism processes, which awaits future investigation.
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Affiliation(s)
- Yanyan Wang
- Shanghai Institute of Immunology, State Key Laboratory of Oncogenes and Related Genes, Department of Immunology and Microbiology, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Fei-Long Meng
- Key Laboratory of RNA Science and Engineering, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai 200031, China.
| | - Leng-Siew Yeap
- Shanghai Institute of Immunology, State Key Laboratory of Oncogenes and Related Genes, Department of Immunology and Microbiology, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China.
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2
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Bello A, Hirth G, Voigt S, Tepper S, Jungnickel B. Mechanism and regulation of secondary immunoglobulin diversification. Cell Cycle 2023; 22:2070-2087. [PMID: 37909747 PMCID: PMC10761156 DOI: 10.1080/15384101.2023.2275397] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Accepted: 10/20/2023] [Indexed: 11/03/2023] Open
Abstract
Secondary immunoglobulin diversification by somatic hypermutation and class switch recombination in B cells is instrumental for an adequate adaptive humoral immune response. These genetic events may, however, also introduce aberrations into other cellular genes and thereby cause B cell malignancies. While the basic mechanism of somatic hypermutation and class switch recombination is now well understood, their regulation and in particular the mechanism of their specific targeting to immunoglobulin genes is still rather mysterious. In this review, we summarize the current knowledge on the mechanism and regulation of secondary immunoglobulin diversification and discuss known mechanisms of physiological targeting to immunoglobulin genes and mistargeting to other cellular genes. We summarize open questions in the field and provide an outlook on future research.
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Affiliation(s)
- Amanda Bello
- Institute of Biochemistry and Biophysics, Faculty of Biological Sciences, Friedrich Schiller University, Jena, Germany
| | - Gianna Hirth
- Institute of Biochemistry and Biophysics, Faculty of Biological Sciences, Friedrich Schiller University, Jena, Germany
| | - Stefanie Voigt
- Institute of Biochemistry and Biophysics, Faculty of Biological Sciences, Friedrich Schiller University, Jena, Germany
| | - Sandra Tepper
- Institute of Biochemistry and Biophysics, Faculty of Biological Sciences, Friedrich Schiller University, Jena, Germany
| | - Berit Jungnickel
- Institute of Biochemistry and Biophysics, Faculty of Biological Sciences, Friedrich Schiller University, Jena, Germany
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3
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Lee JH, Sutton HJ, Cottrell CA, Phung I, Ozorowski G, Sewall LM, Nedellec R, Nakao C, Silva M, Richey ST, Torres JL, Lee WH, Georgeson E, Kubitz M, Hodges S, Mullen TM, Adachi Y, Cirelli KM, Kaur A, Allers C, Fahlberg M, Grasperge BF, Dufour JP, Schiro F, Aye PP, Kalyuzhniy O, Liguori A, Carnathan DG, Silvestri G, Shen X, Montefiori DC, Veazey RS, Ward AB, Hangartner L, Burton DR, Irvine DJ, Schief WR, Crotty S. Long-primed germinal centres with enduring affinity maturation and clonal migration. Nature 2022; 609:998-1004. [PMID: 36131022 PMCID: PMC9491273 DOI: 10.1038/s41586-022-05216-9] [Citation(s) in RCA: 53] [Impact Index Per Article: 26.5] [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: 12/13/2021] [Accepted: 08/09/2022] [Indexed: 02/06/2023]
Abstract
Germinal centres are the engines of antibody evolution. Here, using human immunodeficiency virus (HIV) Env protein immunogen priming in rhesus monkeys followed by a long period without further immunization, we demonstrate germinal centre B (BGC) cells that last for at least 6 months. A 186-fold increase in BGC cells was present by week 10 compared with conventional immunization. Single-cell transcriptional profiling showed that both light- and dark-zone germinal centre states were sustained. Antibody somatic hypermutation of BGC cells continued to accumulate throughout the 29-week priming period, with evidence of selective pressure. Env-binding BGC cells were still 49-fold above baseline at 29 weeks, which suggests that they could remain active for even longer periods of time. High titres of HIV-neutralizing antibodies were generated after a single booster immunization. Fully glycosylated HIV trimer protein is a complex antigen, posing considerable immunodominance challenges for B cells1,2. Memory B cells generated under these long priming conditions had higher levels of antibody somatic hypermutation, and both memory B cells and antibodies were more likely to recognize non-immunodominant epitopes. Numerous BGC cell lineage phylogenies spanning more than the 6-month germinal centre period were identified, demonstrating continuous germinal centre activity and selection for at least 191 days with no further antigen exposure. A long-prime, slow-delivery (12 days) immunization approach holds promise for difficult vaccine targets and suggests that patience can have great value for tuning of germinal centres to maximize antibody responses.
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Affiliation(s)
- Jeong Hyun Lee
- Center for Infectious Disease and Vaccine Research, La Jolla Institute for Immunology, La Jolla, CA, USA
- Consortium for HIV/AIDS Vaccine Development, The Scripps Research Institute, La Jolla, CA, USA
- IAVI Neutralizing Antibody Center, The Scripps Research Institute, La Jolla, CA, USA
| | - Henry J Sutton
- Center for Infectious Disease and Vaccine Research, La Jolla Institute for Immunology, La Jolla, CA, USA
- Consortium for HIV/AIDS Vaccine Development, The Scripps Research Institute, La Jolla, CA, USA
| | - Christopher A Cottrell
- Consortium for HIV/AIDS Vaccine Development, The Scripps Research Institute, La Jolla, CA, USA
- IAVI Neutralizing Antibody Center, The Scripps Research Institute, La Jolla, CA, USA
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA, USA
| | - Ivy Phung
- Center for Infectious Disease and Vaccine Research, La Jolla Institute for Immunology, La Jolla, CA, USA
- Consortium for HIV/AIDS Vaccine Development, The Scripps Research Institute, La Jolla, CA, USA
- Department of Medicine, Division of Infectious Diseases and Global Public Health, University of California, San Diego, La Jolla, CA, USA
| | - Gabriel Ozorowski
- Consortium for HIV/AIDS Vaccine Development, The Scripps Research Institute, La Jolla, CA, USA
- IAVI Neutralizing Antibody Center, The Scripps Research Institute, La Jolla, CA, USA
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, USA
| | - Leigh M Sewall
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, USA
| | - Rebecca Nedellec
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA, USA
| | - Catherine Nakao
- Center for Infectious Disease and Vaccine Research, La Jolla Institute for Immunology, La Jolla, CA, USA
| | - Murillo Silva
- Consortium for HIV/AIDS Vaccine Development, The Scripps Research Institute, La Jolla, CA, USA
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Sara T Richey
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, USA
| | - Jonathan L Torres
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, USA
| | - Wen-Hsin Lee
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, USA
| | - Erik Georgeson
- Consortium for HIV/AIDS Vaccine Development, The Scripps Research Institute, La Jolla, CA, USA
- IAVI Neutralizing Antibody Center, The Scripps Research Institute, La Jolla, CA, USA
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA, USA
| | - Michael Kubitz
- Consortium for HIV/AIDS Vaccine Development, The Scripps Research Institute, La Jolla, CA, USA
- IAVI Neutralizing Antibody Center, The Scripps Research Institute, La Jolla, CA, USA
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA, USA
| | - Sam Hodges
- Consortium for HIV/AIDS Vaccine Development, The Scripps Research Institute, La Jolla, CA, USA
- IAVI Neutralizing Antibody Center, The Scripps Research Institute, La Jolla, CA, USA
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA, USA
| | - Tina-Marie Mullen
- Consortium for HIV/AIDS Vaccine Development, The Scripps Research Institute, La Jolla, CA, USA
- IAVI Neutralizing Antibody Center, The Scripps Research Institute, La Jolla, CA, USA
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA, USA
| | - Yumiko Adachi
- Consortium for HIV/AIDS Vaccine Development, The Scripps Research Institute, La Jolla, CA, USA
- IAVI Neutralizing Antibody Center, The Scripps Research Institute, La Jolla, CA, USA
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA, USA
| | - Kimberly M Cirelli
- Center for Infectious Disease and Vaccine Research, La Jolla Institute for Immunology, La Jolla, CA, USA
- Consortium for HIV/AIDS Vaccine Development, The Scripps Research Institute, La Jolla, CA, USA
| | - Amitinder Kaur
- Tulane National Primate Research Center, Tulane School of Medicine, Covington, LA, USA
| | - Carolina Allers
- Tulane National Primate Research Center, Tulane School of Medicine, Covington, LA, USA
| | - Marissa Fahlberg
- Tulane National Primate Research Center, Tulane School of Medicine, Covington, LA, USA
| | - Brooke F Grasperge
- Tulane National Primate Research Center, Tulane School of Medicine, Covington, LA, USA
| | - Jason P Dufour
- Tulane National Primate Research Center, Tulane School of Medicine, Covington, LA, USA
| | - Faith Schiro
- Tulane National Primate Research Center, Tulane School of Medicine, Covington, LA, USA
| | - Pyone P Aye
- Tulane National Primate Research Center, Tulane School of Medicine, Covington, LA, USA
| | - Oleksandr Kalyuzhniy
- Consortium for HIV/AIDS Vaccine Development, The Scripps Research Institute, La Jolla, CA, USA
- IAVI Neutralizing Antibody Center, The Scripps Research Institute, La Jolla, CA, USA
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA, USA
| | - Alessia Liguori
- Consortium for HIV/AIDS Vaccine Development, The Scripps Research Institute, La Jolla, CA, USA
- IAVI Neutralizing Antibody Center, The Scripps Research Institute, La Jolla, CA, USA
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA, USA
| | - Diane G Carnathan
- Consortium for HIV/AIDS Vaccine Development, The Scripps Research Institute, La Jolla, CA, USA
- Emory National Primate Research Center and Emory Vaccine Center, Emory University School of Medicine, Atlanta, GA, USA
| | - Guido Silvestri
- Consortium for HIV/AIDS Vaccine Development, The Scripps Research Institute, La Jolla, CA, USA
- Emory National Primate Research Center and Emory Vaccine Center, Emory University School of Medicine, Atlanta, GA, USA
| | - Xiaoying Shen
- Department of Surgery, Laboratory for AIDS Vaccine Research & Development, Duke University Medical Center, Duke University, Durham, NC, USA
| | - David C Montefiori
- Department of Surgery, Laboratory for AIDS Vaccine Research & Development, Duke University Medical Center, Duke University, Durham, NC, USA
| | - Ronald S Veazey
- Tulane National Primate Research Center, Tulane School of Medicine, Covington, LA, USA
| | - Andrew B Ward
- Consortium for HIV/AIDS Vaccine Development, The Scripps Research Institute, La Jolla, CA, USA
- IAVI Neutralizing Antibody Center, The Scripps Research Institute, La Jolla, CA, USA
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, USA
| | - Lars Hangartner
- Consortium for HIV/AIDS Vaccine Development, The Scripps Research Institute, La Jolla, CA, USA
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA, USA
| | - Dennis R Burton
- Consortium for HIV/AIDS Vaccine Development, The Scripps Research Institute, La Jolla, CA, USA
- IAVI Neutralizing Antibody Center, The Scripps Research Institute, La Jolla, CA, USA
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA, USA
- Ragon Institute of Massachusetts General Hospital, Massachusetts Institute of Technology and Harvard University, Cambridge, MA, USA
| | - Darrell J Irvine
- Consortium for HIV/AIDS Vaccine Development, The Scripps Research Institute, La Jolla, CA, USA
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, USA
- Ragon Institute of Massachusetts General Hospital, Massachusetts Institute of Technology and Harvard University, Cambridge, MA, USA
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
- Howard Hughes Medical Institute, Chevy Chase, MD, USA
| | - William R Schief
- Consortium for HIV/AIDS Vaccine Development, The Scripps Research Institute, La Jolla, CA, USA
- IAVI Neutralizing Antibody Center, The Scripps Research Institute, La Jolla, CA, USA
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA, USA
- Ragon Institute of Massachusetts General Hospital, Massachusetts Institute of Technology and Harvard University, Cambridge, MA, USA
| | - Shane Crotty
- Center for Infectious Disease and Vaccine Research, La Jolla Institute for Immunology, La Jolla, CA, USA.
- Consortium for HIV/AIDS Vaccine Development, The Scripps Research Institute, La Jolla, CA, USA.
- Department of Medicine, Division of Infectious Diseases and Global Public Health, University of California, San Diego, La Jolla, CA, USA.
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4
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Wu L, Shukla V, Yadavalli AD, Dinesh RK, Xu D, Rao A, Schatz DG. HMCES protects immunoglobulin genes specifically from deletions during somatic hypermutation. Genes Dev 2022; 36:433-450. [PMID: 35450882 PMCID: PMC9067407 DOI: 10.1101/gad.349438.122] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [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: 01/30/2022] [Accepted: 03/29/2022] [Indexed: 01/07/2023]
Abstract
Somatic hypermutation (SHM) produces point mutations in immunoglobulin (Ig) genes in B cells when uracils created by the activation-induced deaminase are processed in a mutagenic manner by enzymes of the base excision repair (BER) and mismatch repair (MMR) pathways. Such uracil processing creates DNA strand breaks and is susceptible to the generation of deleterious deletions. Here, we demonstrate that the DNA repair factor HMCES strongly suppresses deletions without significantly affecting other parameters of SHM in mouse and human B cells, thereby facilitating the production of antigen-specific antibodies. The deletion-prone repair pathway suppressed by HMCES operates downstream from the uracil glycosylase UNG and is mediated by the combined action of BER factor APE2 and MMR factors MSH2, MSH6, and EXO1. HMCES's ability to shield against deletions during SHM requires its capacity to form covalent cross-links with abasic sites, in sharp contrast to its DNA end-joining role in class switch recombination but analogous to its genome-stabilizing role during DNA replication. Our findings lead to a novel model for the protection of Ig gene integrity during SHM in which abasic site cross-linking by HMCES intercedes at a critical juncture during processing of vulnerable gapped DNA intermediates by BER and MMR enzymes.
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Affiliation(s)
- Lizhen Wu
- Department of Immunobiology, Yale School of Medicine, New Haven, Connecticut 06520, USA
| | - Vipul Shukla
- Division of Signaling and Gene Expression, La Jolla Institute for Immunology, La Jolla, California 92037, USA
| | | | - Ravi K Dinesh
- Department of Immunobiology, Yale School of Medicine, New Haven, Connecticut 06520, USA
| | - Dijin Xu
- Department of Microbial Pathogenesis, Yale University School of Medicine, New Haven, Connecticut 06510, USA
| | - Anjana Rao
- Division of Signaling and Gene Expression, La Jolla Institute for Immunology, La Jolla, California 92037, USA
- Department of Pharmacology, Moores Cancer Center, University of California at San Diego, La Jolla, California 92093, USA
- Consortium for Regenerative Medicine, La Jolla, California 92037, USA
| | - David G Schatz
- Department of Immunobiology, Yale School of Medicine, New Haven, Connecticut 06520, USA
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5
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Dirks J, Haase G, Cantaert T, Frey L, Klaas M, Rickert CH, Girschick H, Meffre E, Morbach H. A Novel AICDA Splice-Site Mutation in Two Siblings with HIGM2 Permits Somatic Hypermutation but Abrogates Mutational Targeting. J Clin Immunol 2022; 42:771-782. [PMID: 35246784 PMCID: PMC9166864 DOI: 10.1007/s10875-022-01233-5] [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: 12/02/2021] [Accepted: 02/14/2022] [Indexed: 11/29/2022]
Abstract
Hyper-IgM syndrome type 2 (HIGM2) is a B cell intrinsic primary immunodeficiency caused by mutations in AICDA encoding activation-induced cytidine deaminase (AID) which impair immunoglobulin class switch recombination (CSR) and somatic hypermutation (SHM). Whereas autosomal-recessive AID-deficiency (AR-AID) affects both CSR and SHM, the autosomal-dominant form (AD-AID) due to C-terminal heterozygous variants completely abolishes CSR but only partially affects SHM. AR-AID patients display enhanced germinal center (GC) reactions and autoimmune manifestations, which are not present in AD-AID, suggesting that SHM but not CSR regulates GC reactions and peripheral B cell tolerance. Herein, we describe two siblings with HIGM2 due to a novel homozygous AICDA mutation (c.428-1G > T) which disrupts the splice acceptor site of exon 4 and results in the sole expression of a truncated AID variant that lacks 10 highly conserved amino acids encoded by exon 4 (AID-ΔE4a). AID-ΔE4a patients suffered from defective CSR and enhanced GC reactions and were therefore indistinguishable from other AR-AID patients. However, the AID-ΔE4a variant only partially affected SHM as observed in AD-AID patients. In addition, AID-ΔE4a but not AD-AID patients revealed impaired targeting of mutational hotspot motives and distorted mutational patterns. Hence, qualitative defects in AID function and altered SHM rather than global decreased SHM activity may account for the disease phenotype in these patients.
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Affiliation(s)
- Johannes Dirks
- Pediatric Immunology, University Childrens' Hospital Würzburg, Würzburg, Germany
| | - Gabriele Haase
- Pediatric Immunology, University Childrens' Hospital Würzburg, Würzburg, Germany
| | - Tineke Cantaert
- Immunology Unit, Institut Pasteur du Cambodge, Phnom Penh, Cambodia
| | - Lea Frey
- Institute of Pathology, Würzburg University, Würzburg, Germany
| | - Moritz Klaas
- Pediatric Rheumatology, Vivantes Hospital Friedrichshain, Berlin, Germany
| | | | - Hermann Girschick
- Pediatric Rheumatology, Vivantes Hospital Friedrichshain, Berlin, Germany
- German Center for Growth and Development "DEUZWEG", Berlin, Germany
| | - Eric Meffre
- Department of Immunobiology, Yale University School of Medicine, New Haven, CT, USA
| | - Henner Morbach
- Pediatric Immunology, University Childrens' Hospital Würzburg, Würzburg, Germany.
- Center for Rare Diseases - Reference Center Northern Bavaria (ZESE), Würzburg, Germany.
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6
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Rogier M, Moritz J, Robert I, Lescale C, Heyer V, Abello A, Martin O, Capitani K, Thomas M, Thomas-Claudepierre AS, Laffleur B, Jouan F, Pinaud E, Tarte K, Cogné M, Conticello SG, Soutoglou E, Deriano L, Reina-San-Martin B. Fam72a enforces error-prone DNA repair during antibody diversification. Nature 2021; 600:329-333. [PMID: 34819671 DOI: 10.1038/s41586-021-04093-y] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Accepted: 10/04/2021] [Indexed: 12/26/2022]
Abstract
Efficient humoral responses rely on DNA damage, mutagenesis and error-prone DNA repair. Diversification of B cell receptors through somatic hypermutation and class-switch recombination are initiated by cytidine deamination in DNA mediated by activation-induced cytidine deaminase (AID)1 and by the subsequent excision of the resulting uracils by uracil DNA glycosylase (UNG) and by mismatch repair proteins1-3. Although uracils arising in DNA are accurately repaired1-4, how these pathways are co-opted to generate mutations and double-strand DNA breaks in the context of somatic hypermutation and class-switch recombination is unknown1-3. Here we performed a genome-wide CRISPR-Cas9 knockout screen for genes involved in class-switch recombination and identified FAM72A, a protein that interacts with the nuclear isoform of UNG (UNG2)5 and is overexpressed in several cancers5. We show that the FAM72A-UNG2 interaction controls the levels of UNG2 and that class-switch recombination is defective in Fam72a-/- B cells due to the upregulation of UNG2. Moreover, we show that somatic hypermutation is reduced in Fam72a-/- B cells and that its pattern is skewed upon upregulation of UNG2. Our results are consistent with a model in which FAM72A interacts with UNG2 to control its physiological level by triggering its degradation, regulating the level of uracil excision and thus the balance between error-prone and error-free DNA repair. Our findings have potential implications for tumorigenesis, as reduced levels of UNG2 mediated by overexpression of Fam72a would shift the balance towards mutagenic DNA repair, rendering cells more prone to acquire mutations.
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Affiliation(s)
- Mélanie Rogier
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Illkirch, France
- Institut National de la Santé et de la Recherche Médicale (INSERM), U1258, Illkirch, France
- Centre National de la Recherche Scientifique (CNRS), UMR7104, Illkirch, France
- Université de Strasbourg, Illkirch, France
| | - Jacques Moritz
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Illkirch, France
- Institut National de la Santé et de la Recherche Médicale (INSERM), U1258, Illkirch, France
- Centre National de la Recherche Scientifique (CNRS), UMR7104, Illkirch, France
- Université de Strasbourg, Illkirch, France
| | - Isabelle Robert
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Illkirch, France
- Institut National de la Santé et de la Recherche Médicale (INSERM), U1258, Illkirch, France
- Centre National de la Recherche Scientifique (CNRS), UMR7104, Illkirch, France
- Université de Strasbourg, Illkirch, France
| | - Chloé Lescale
- Genome Integrity, Immunity and Cancer Unit, Equipe Labellisée Ligue Contre Le Cancer, INSERM U1223, Institut Pasteur, Paris, France
| | - Vincent Heyer
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Illkirch, France
- Institut National de la Santé et de la Recherche Médicale (INSERM), U1258, Illkirch, France
- Centre National de la Recherche Scientifique (CNRS), UMR7104, Illkirch, France
- Université de Strasbourg, Illkirch, France
| | - Arthur Abello
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Illkirch, France
- Institut National de la Santé et de la Recherche Médicale (INSERM), U1258, Illkirch, France
- Centre National de la Recherche Scientifique (CNRS), UMR7104, Illkirch, France
- Université de Strasbourg, Illkirch, France
| | - Ophélie Martin
- Genome Damage and Stability Centre, School of Life Sciences, University of Sussex, Brighton, UK
| | - Katia Capitani
- Core Research Laboratory, ISPRO, Firenze, Italy
- Department of Medical Biotechnologies, University of Siena, Siena, Italy
| | - Morgane Thomas
- Centre National de la Recherche Scientifique (CNRS), UMR7276, Institut National de la Santé et de la Recherche Médicale (INSERM), UMR1262-Contrôle de la Réponse Immune B et Lymphoproliférations, Université de Limoges, Limoges, France
| | - Anne-Sophie Thomas-Claudepierre
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Illkirch, France
- Institut National de la Santé et de la Recherche Médicale (INSERM), U1258, Illkirch, France
- Centre National de la Recherche Scientifique (CNRS), UMR7104, Illkirch, France
- Université de Strasbourg, Illkirch, France
| | - Brice Laffleur
- Institut national de la santé et de la recherche médicale (INSERM), UMR1236, Université Rennes 1, Etablissement Français du Sang Bretagne, Rennes, France
| | - Florence Jouan
- Institut national de la santé et de la recherche médicale (INSERM), UMR1236, Université Rennes 1, Etablissement Français du Sang Bretagne, Rennes, France
| | - Eric Pinaud
- Centre National de la Recherche Scientifique (CNRS), UMR7276, Institut National de la Santé et de la Recherche Médicale (INSERM), UMR1262-Contrôle de la Réponse Immune B et Lymphoproliférations, Université de Limoges, Limoges, France
| | - Karin Tarte
- Institut national de la santé et de la recherche médicale (INSERM), UMR1236, Université Rennes 1, Etablissement Français du Sang Bretagne, Rennes, France
| | - Michel Cogné
- Centre National de la Recherche Scientifique (CNRS), UMR7276, Institut National de la Santé et de la Recherche Médicale (INSERM), UMR1262-Contrôle de la Réponse Immune B et Lymphoproliférations, Université de Limoges, Limoges, France
- Institut national de la santé et de la recherche médicale (INSERM), UMR1236, Université Rennes 1, Etablissement Français du Sang Bretagne, Rennes, France
| | - Silvestro G Conticello
- Core Research Laboratory, ISPRO, Firenze, Italy
- Institute of Clinical Physiology, National Research Council, Pisa, Italy
| | - Evi Soutoglou
- Genome Damage and Stability Centre, School of Life Sciences, University of Sussex, Brighton, UK
| | - Ludovic Deriano
- Genome Integrity, Immunity and Cancer Unit, Equipe Labellisée Ligue Contre Le Cancer, INSERM U1223, Institut Pasteur, Paris, France
| | - Bernardo Reina-San-Martin
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Illkirch, France.
- Institut National de la Santé et de la Recherche Médicale (INSERM), U1258, Illkirch, France.
- Centre National de la Recherche Scientifique (CNRS), UMR7104, Illkirch, France.
- Université de Strasbourg, Illkirch, France.
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7
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Feng Y, Li C, Stewart JA, Barbulescu P, Seija Desivo N, Álvarez-Quilón A, Pezo RC, Perera MLW, Chan K, Tong AHY, Mohamad-Ramshan R, Berru M, Nakib D, Li G, Kardar GA, Carlyle JR, Moffat J, Durocher D, Di Noia JM, Bhagwat AS, Martin A. FAM72A antagonizes UNG2 to promote mutagenic repair during antibody maturation. Nature 2021; 600:324-328. [PMID: 34819670 PMCID: PMC9425297 DOI: 10.1038/s41586-021-04144-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [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: 12/16/2020] [Accepted: 10/14/2021] [Indexed: 11/09/2022]
Abstract
Activation-induced cytidine deaminase (AID) catalyses the deamination of deoxycytidines to deoxyuracils within immunoglobulin genes to induce somatic hypermutation and class-switch recombination1,2. AID-generated deoxyuracils are recognized and processed by subverted base-excision and mismatch repair pathways that ensure a mutagenic outcome in B cells3-6. However, why these DNA repair pathways do not accurately repair AID-induced lesions remains unknown. Here, using a genome-wide CRISPR screen, we show that FAM72A is a major determinant for the error-prone processing of deoxyuracils. Fam72a-deficient CH12F3-2 B cells and primary B cells from Fam72a-/- mice exhibit reduced class-switch recombination and somatic hypermutation frequencies at immunoglobulin and Bcl6 genes, and reduced genome-wide deoxyuracils. The somatic hypermutation spectrum in B cells from Fam72a-/- mice is opposite to that observed in mice deficient in uracil DNA glycosylase 2 (UNG2)7, which suggests that UNG2 is hyperactive in FAM72A-deficient cells. Indeed, FAM72A binds to UNG2, resulting in reduced levels of UNG2 protein in the G1 phase of the cell cycle, coinciding with peak AID activity. FAM72A therefore causes U·G mispairs to persist into S phase, leading to error-prone processing by mismatch repair. By disabling the DNA repair pathways that normally efficiently remove deoxyuracils from DNA, FAM72A enables AID to exert its full effects on antibody maturation. This work has implications in cancer, as the overexpression of FAM72A that is observed in many cancers8 could promote mutagenesis.
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Affiliation(s)
- Yuqing Feng
- Department of Immunology, University of Toronto, Toronto, Ontario, Canada
| | - Conglei Li
- Department of Immunology, University of Toronto, Toronto, Ontario, Canada
- School of Medicine, The Chinese University of Hong Kong, Shenzhen, China
| | | | - Philip Barbulescu
- Department of Immunology, University of Toronto, Toronto, Ontario, Canada
| | - Noé Seija Desivo
- Institut de recherches cliniques de Montréal, Montreal, Quebec, Canada
- Molecular Biology Programs, Department of Medicine, University of Montreal, Montreal, Quebec, Canada
| | - Alejandro Álvarez-Quilón
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
- Lunenfeld-Tanenbaum Research Institute, Sinai Health System, Toronto, Ontario, Canada
| | - Rossanna C Pezo
- Sunnybrook Health Sciences Center, Toronto, Ontario, Canada
- Department of Medicine, University of Toronto, Toronto, Ontario, Canada
| | | | - Katherine Chan
- Donnelly Centre, University of Toronto, Toronto, Ontario, Canada
| | - Amy Hin Yan Tong
- Donnelly Centre, University of Toronto, Toronto, Ontario, Canada
| | | | - Maribel Berru
- Department of Immunology, University of Toronto, Toronto, Ontario, Canada
| | - Diana Nakib
- Department of Immunology, University of Toronto, Toronto, Ontario, Canada
| | - Gavin Li
- Department of Immunology, University of Toronto, Toronto, Ontario, Canada
| | - Gholam Ali Kardar
- Immunology, Asthma and Allergy Research Institute, Tehran University of Medical Sciences, Tehran, Iran
| | - James R Carlyle
- Department of Immunology, University of Toronto, Toronto, Ontario, Canada
| | - Jason Moffat
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
- Donnelly Centre, University of Toronto, Toronto, Ontario, Canada
- Institute for Biomedical Engineering, University of Toronto, Toronto, Ontario, Canada
| | - Daniel Durocher
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
- Lunenfeld-Tanenbaum Research Institute, Sinai Health System, Toronto, Ontario, Canada
| | - Javier M Di Noia
- Institut de recherches cliniques de Montréal, Montreal, Quebec, Canada
- Molecular Biology Programs, Department of Medicine, University of Montreal, Montreal, Quebec, Canada
| | - Ashok S Bhagwat
- Department of Chemistry, Wayne State University, Detroit, MI, USA
- Department of Biochemistry, Microbiology and Immunology, Wayne State University School of Medicine, Detroit, MI, USA
| | - Alberto Martin
- Department of Immunology, University of Toronto, Toronto, Ontario, Canada.
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8
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Bartsch T, Arndt C, Loureiro LR, Kegler A, Puentes-Cala E, Soto JA, Kurien BT, Feldmann A, Berndt N, Bachmann MP. A Small Step, a Giant Leap: Somatic Hypermutation of a Single Amino Acid Leads to Anti-La Autoreactivity. Int J Mol Sci 2021; 22:ijms222112046. [PMID: 34769474 PMCID: PMC8584381 DOI: 10.3390/ijms222112046] [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] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Revised: 11/03/2021] [Accepted: 11/05/2021] [Indexed: 11/16/2022] Open
Abstract
The anti-La mab 312B, which was established by hybridoma technology from human-La transgenic mice after adoptive transfer of anti-human La T cells, immunoprecipitates both native eukaryotic human and murine La protein. Therefore, it represents a true anti-La autoantibody. During maturation, the anti-La mab 312B acquired somatic hypermutations (SHMs) which resulted in the replacement of four aa in the complementarity determining regions (CDR) and seven aa in the framework regions. The recombinant derivative of the anti-La mab 312B in which all the SHMs were corrected to the germline sequence failed to recognize the La antigen. We therefore wanted to learn which SHM(s) is (are) responsible for anti-La autoreactivity. Humanization of the 312B ab by grafting its CDR regions to a human Ig backbone confirms that the CDR sequences are mainly responsible for anti-La autoreactivity. Finally, we identified that a single amino acid replacement (D > Y) in the germline sequence of the CDR3 region of the heavy chain of the anti-La mab 312B is sufficient for anti-La autoreactivity.
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Affiliation(s)
- Tabea Bartsch
- Department of Radioimmunology, Institute of Radiopharmaceutical Cancer Research, Helmholtz-Zentrum Dresden-Rossendorf (HZDR), 01328 Dresden, Germany; (T.B.); (C.A.); (L.R.L.); (A.K.); (E.P.-C.); (J.A.S.); (A.F.); (N.B.)
| | - Claudia Arndt
- Department of Radioimmunology, Institute of Radiopharmaceutical Cancer Research, Helmholtz-Zentrum Dresden-Rossendorf (HZDR), 01328 Dresden, Germany; (T.B.); (C.A.); (L.R.L.); (A.K.); (E.P.-C.); (J.A.S.); (A.F.); (N.B.)
| | - Liliana R. Loureiro
- Department of Radioimmunology, Institute of Radiopharmaceutical Cancer Research, Helmholtz-Zentrum Dresden-Rossendorf (HZDR), 01328 Dresden, Germany; (T.B.); (C.A.); (L.R.L.); (A.K.); (E.P.-C.); (J.A.S.); (A.F.); (N.B.)
| | - Alexandra Kegler
- Department of Radioimmunology, Institute of Radiopharmaceutical Cancer Research, Helmholtz-Zentrum Dresden-Rossendorf (HZDR), 01328 Dresden, Germany; (T.B.); (C.A.); (L.R.L.); (A.K.); (E.P.-C.); (J.A.S.); (A.F.); (N.B.)
| | - Edinson Puentes-Cala
- Department of Radioimmunology, Institute of Radiopharmaceutical Cancer Research, Helmholtz-Zentrum Dresden-Rossendorf (HZDR), 01328 Dresden, Germany; (T.B.); (C.A.); (L.R.L.); (A.K.); (E.P.-C.); (J.A.S.); (A.F.); (N.B.)
- Corporación para la Investigación de la Corrosión (CIC), Piedecuesta 681011, Colombia
| | - Javier Andrés Soto
- Department of Radioimmunology, Institute of Radiopharmaceutical Cancer Research, Helmholtz-Zentrum Dresden-Rossendorf (HZDR), 01328 Dresden, Germany; (T.B.); (C.A.); (L.R.L.); (A.K.); (E.P.-C.); (J.A.S.); (A.F.); (N.B.)
- BIOGEN Research Group, University of Santander, Faculty of Health Sciences, Cúcuta 540001, Colombia
| | - Biji T. Kurien
- The Arthritis and Clinical Immunology Program, Oklahoma Medical Research Foundation, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA;
| | - Anja Feldmann
- Department of Radioimmunology, Institute of Radiopharmaceutical Cancer Research, Helmholtz-Zentrum Dresden-Rossendorf (HZDR), 01328 Dresden, Germany; (T.B.); (C.A.); (L.R.L.); (A.K.); (E.P.-C.); (J.A.S.); (A.F.); (N.B.)
| | - Nicole Berndt
- Department of Radioimmunology, Institute of Radiopharmaceutical Cancer Research, Helmholtz-Zentrum Dresden-Rossendorf (HZDR), 01328 Dresden, Germany; (T.B.); (C.A.); (L.R.L.); (A.K.); (E.P.-C.); (J.A.S.); (A.F.); (N.B.)
| | - Michael P. Bachmann
- Department of Radioimmunology, Institute of Radiopharmaceutical Cancer Research, Helmholtz-Zentrum Dresden-Rossendorf (HZDR), 01328 Dresden, Germany; (T.B.); (C.A.); (L.R.L.); (A.K.); (E.P.-C.); (J.A.S.); (A.F.); (N.B.)
- BIOGEN Research Group, University of Santander, Faculty of Health Sciences, Cúcuta 540001, Colombia
- The Arthritis and Clinical Immunology Program, Oklahoma Medical Research Foundation, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA;
- Tumor Immunology, University Cancer Center (UCC), University Hospital Carl Gustav Carus Dresden, TU Dresden, 01307 Dresden, Germany
- National Center for Tumor Diseases (NCT), 03128 Dresden, Germany
- Correspondence: ; Tel.: +49-351-260-3223
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9
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Amanat F, Thapa M, Lei T, Ahmed SMS, Adelsberg DC, Carreño JM, Strohmeier S, Schmitz AJ, Zafar S, Zhou JQ, Rijnink W, Alshammary H, Borcherding N, Reiche AG, Srivastava K, Sordillo EM, van Bakel H, Turner JS, Bajic G, Simon V, Ellebedy AH, Krammer F. SARS-CoV-2 mRNA vaccination induces functionally diverse antibodies to NTD, RBD, and S2. Cell 2021; 184:3936-3948.e10. [PMID: 34192529 PMCID: PMC8185186 DOI: 10.1016/j.cell.2021.06.005] [Citation(s) in RCA: 185] [Impact Index Per Article: 61.7] [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: 03/09/2021] [Revised: 05/14/2021] [Accepted: 06/02/2021] [Indexed: 01/12/2023]
Abstract
In this study we profiled vaccine-induced polyclonal antibodies as well as plasmablast-derived mAbs from individuals who received SARS-CoV-2 spike mRNA vaccine. Polyclonal antibody responses in vaccinees were robust and comparable to or exceeded those seen after natural infection. However, the ratio of binding to neutralizing antibodies after vaccination was greater than that after natural infection and, at the monoclonal level, we found that the majority of vaccine-induced antibodies did not have neutralizing activity. We also found a co-dominance of mAbs targeting the NTD and RBD of SARS-CoV-2 spike and an original antigenic-sin like backboost to spikes of seasonal human coronaviruses OC43 and HKU1. Neutralizing activity of NTD mAbs but not RBD mAbs against a clinical viral isolate carrying E484K as well as extensive changes in the NTD was abolished, suggesting that a proportion of vaccine-induced RBD binding antibodies may provide substantial protection against viral variants carrying single E484K RBD mutations.
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Affiliation(s)
- Fatima Amanat
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA; Graduate School of Biomedical Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Mahima Thapa
- Department of Pathology & Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Tinting Lei
- Department of Pathology & Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Shaza M Sayed Ahmed
- Department of Pathology & Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Daniel C Adelsberg
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Juan Manuel Carreño
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Shirin Strohmeier
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Aaron J Schmitz
- Department of Pathology & Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Sarah Zafar
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Julian Q Zhou
- AbCellera Biologics Inc., Vancouver, BC V5Y 0A1, Canada
| | - Willemijn Rijnink
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Hala Alshammary
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Nicholas Borcherding
- Department of Pathology & Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Ana Gonzalez Reiche
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Komal Srivastava
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Emilia Mia Sordillo
- Department of Pathology, Molecular and Cell Based Medicine, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Harm van Bakel
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA; Icahn Institute for Data Science and Genomic Technology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Jackson S Turner
- Department of Pathology & Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Goran Bajic
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA.
| | - Viviana Simon
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA; Division of Infectious Diseases, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA; The Global Health and Emerging Pathogens Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA.
| | - Ali H Ellebedy
- Department of Pathology & Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA; Andrew M. and Jane M. Bursky Center for Human Immunology and Immunotherapy Programs, Washington University School of Medicine, Saint Louis, MO 63110, USA; Center for Vaccines and Immunity to Microbial Pathogens, Washington University School of Medicine, Saint Louis, MO 63110, USA.
| | - Florian Krammer
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA.
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10
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Xu J, Xu K, Jung S, Conte A, Lieberman J, Muecksch F, Lorenzi JCC, Park S, Schmidt F, Wang Z, Huang Y, Luo Y, Nair MS, Wang P, Schulz JE, Tessarollo L, Bylund T, Chuang GY, Olia AS, Stephens T, Teng IT, Tsybovsky Y, Zhou T, Munster V, Ho DD, Hatziioannou T, Bieniasz PD, Nussenzweig MC, Kwong PD, Casellas R. Nanobodies from camelid mice and llamas neutralize SARS-CoV-2 variants. Nature 2021; 595:278-282. [PMID: 34098567 PMCID: PMC8260353 DOI: 10.1038/s41586-021-03676-z] [Citation(s) in RCA: 132] [Impact Index Per Article: 44.0] [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: 03/04/2021] [Accepted: 05/27/2021] [Indexed: 11/08/2022]
Abstract
Since the start of the COVID-19 pandemic, SARS-CoV-2 has caused millions of deaths worldwide. Although a number of vaccines have been deployed, the continual evolution of the receptor-binding domain (RBD) of the virus has challenged their efficacy. In particular, the emerging variants B.1.1.7, B.1.351 and P.1 (first detected in the UK, South Africa and Brazil, respectively) have compromised the efficacy of sera from patients who have recovered from COVID-19 and immunotherapies that have received emergency use authorization1-3. One potential alternative to avert viral escape is the use of camelid VHHs (variable heavy chain domains of heavy chain antibody (also known as nanobodies)), which can recognize epitopes that are often inaccessible to conventional antibodies4. Here, we isolate anti-RBD nanobodies from llamas and from mice that we engineered to produce VHHs cloned from alpacas, dromedaries and Bactrian camels. We identified two groups of highly neutralizing nanobodies. Group 1 circumvents antigenic drift by recognizing an RBD region that is highly conserved in coronaviruses but rarely targeted by human antibodies. Group 2 is almost exclusively focused to the RBD-ACE2 interface and does not neutralize SARS-CoV-2 variants that carry E484K or N501Y substitutions. However, nanobodies in group 2 retain full neutralization activity against these variants when expressed as homotrimers, and-to our knowledge-rival the most potent antibodies against SARS-CoV-2 that have been produced to date. These findings suggest that multivalent nanobodies overcome SARS-CoV-2 mutations through two separate mechanisms: enhanced avidity for the ACE2-binding domain and recognition of conserved epitopes that are largely inaccessible to human antibodies. Therefore, although new SARS-CoV-2 mutants will continue to emerge, nanobodies represent promising tools to prevent COVID-19 mortality when vaccines are compromised.
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MESH Headings
- Animals
- Antibodies, Neutralizing/chemistry
- Antibodies, Neutralizing/genetics
- Antibodies, Neutralizing/immunology
- Antibodies, Neutralizing/isolation & purification
- CRISPR-Cas Systems
- Camelids, New World/genetics
- Camelids, New World/immunology
- Female
- Gene Editing
- Humans
- Male
- Mice
- Mice, Inbred C57BL
- Models, Molecular
- Mutation
- Neutralization Tests
- SARS-CoV-2/chemistry
- SARS-CoV-2/genetics
- SARS-CoV-2/immunology
- Single-Domain Antibodies/chemistry
- Single-Domain Antibodies/genetics
- Single-Domain Antibodies/immunology
- Single-Domain Antibodies/isolation & purification
- Somatic Hypermutation, Immunoglobulin/genetics
- Spike Glycoprotein, Coronavirus/chemistry
- Spike Glycoprotein, Coronavirus/immunology
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Affiliation(s)
- Jianliang Xu
- Lymphocyte Nuclear Biology, NIAMS, NIH, Bethesda, MD, USA.
| | - Kai Xu
- Vaccine Research Center, NIAID, NIH, Bethesda, MD, USA
- Department of Veterinary Biosciences, College of Veterinary Medicine, The Ohio State University, Columbus, OH, USA
| | | | - Andrea Conte
- Lymphocyte Nuclear Biology, NIAMS, NIH, Bethesda, MD, USA
| | | | - Frauke Muecksch
- Laboratory of Retrovirology, The Rockefeller University, New York, NY, USA
| | | | - Solji Park
- Lymphocyte Nuclear Biology, NIAMS, NIH, Bethesda, MD, USA
| | - Fabian Schmidt
- Laboratory of Retrovirology, The Rockefeller University, New York, NY, USA
| | - Zijun Wang
- Laboratory of Molecular Immunology, The Rockefeller University, New York, NY, USA
| | - Yaoxing Huang
- Aaron Diamond AIDS Research Center, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA
| | - Yang Luo
- Aaron Diamond AIDS Research Center, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA
| | - Manoj S Nair
- Aaron Diamond AIDS Research Center, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA
| | - Pengfei Wang
- Aaron Diamond AIDS Research Center, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA
| | - Jonathan E Schulz
- Laboratory of Virology, Division of Intramural Research, NIAID, NIH, Rocky Mountain Laboratories, Hamilton, MT, USA
| | - Lino Tessarollo
- Mouse Cancer Genetics Program, CCR, NCI, NIH, Frederick, MD, USA
| | | | - Gwo-Yu Chuang
- Vaccine Research Center, NIAID, NIH, Bethesda, MD, USA
| | - Adam S Olia
- Vaccine Research Center, NIAID, NIH, Bethesda, MD, USA
| | - Tyler Stephens
- Electron Microscopy Laboratory, Cancer Research Technology Program, Frederick National Laboratory for Cancer Research sponsored by the National Cancer Institute, Frederick, MD, USA
| | - I-Ting Teng
- Vaccine Research Center, NIAID, NIH, Bethesda, MD, USA
| | - Yaroslav Tsybovsky
- Electron Microscopy Laboratory, Cancer Research Technology Program, Frederick National Laboratory for Cancer Research sponsored by the National Cancer Institute, Frederick, MD, USA
| | - Tongqing Zhou
- Vaccine Research Center, NIAID, NIH, Bethesda, MD, USA
| | - Vincent Munster
- Laboratory of Virology, Division of Intramural Research, NIAID, NIH, Rocky Mountain Laboratories, Hamilton, MT, USA
| | - David D Ho
- Aaron Diamond AIDS Research Center, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA
| | | | - Paul D Bieniasz
- Laboratory of Retrovirology, The Rockefeller University, New York, NY, USA
- Howard Hughes Medical Institute, The Rockefeller University, New York, NY, USA
| | - Michel C Nussenzweig
- Laboratory of Molecular Immunology, The Rockefeller University, New York, NY, USA.
- Howard Hughes Medical Institute, The Rockefeller University, New York, NY, USA.
| | - Peter D Kwong
- Vaccine Research Center, NIAID, NIH, Bethesda, MD, USA.
| | - Rafael Casellas
- Lymphocyte Nuclear Biology, NIAMS, NIH, Bethesda, MD, USA.
- The NIH Regulome Project, NIH, Bethesda, MD, USA.
- Center for Cancer Research, NCI, NIH, Bethesda, MD, USA.
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11
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Fukuyama J, Olson BJ, Matsen FA. Lack of Evidence for a Substantial Rate of Templated Mutagenesis in B Cell Diversification. J Immunol 2020; 205:936-944. [PMID: 32669310 PMCID: PMC7593666 DOI: 10.4049/jimmunol.2000092] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Accepted: 06/17/2020] [Indexed: 11/19/2022]
Abstract
BCR sequences diversify through mutations introduced by purpose-built cellular machinery. A recent paper has concluded that a "templated mutagenesis" process is a major contributor to somatic hypermutation and therefore Ig diversification in mice and humans. In this proposed process, mutations in the Ig locus are introduced by copying short segments from other Ig genes. If true, this would overturn decades of research on B cell diversification and would require a complete rewrite of computational methods to analyze B cell data for these species. In this paper, we re-evaluate the templated mutagenesis hypothesis. By applying the original inferential method using potential donor templates absent from B cell genomes, we obtain estimates of the methods' false positive rates. We find false positive rates of templated mutagenesis in murine and human Ig loci that are similar to or even higher than the original rate inferences, and by considering the bases used in substitution, we find evidence that if templated mutagenesis occurs, it is at a low rate. We also show that the statistically significant results in the original paper can easily result from a slight misspecification of the null model.
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Affiliation(s)
- Julia Fukuyama
- Department of Statistics, Indiana University Bloomington, Bloomington, IN 47408
| | - Branden J Olson
- Program in Computational Biology, Fred Hutchinson Cancer Research Center, Seattle, WA 98109; and
- Department of Statistics, University of Washington, Seattle, WA 98195
| | - Frederick A Matsen
- Program in Computational Biology, Fred Hutchinson Cancer Research Center, Seattle, WA 98109; and
- Department of Statistics, University of Washington, Seattle, WA 98195
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12
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Dhar A, Ralph DK, Minin VN, Matsen FA. A Bayesian phylogenetic hidden Markov model for B cell receptor sequence analysis. PLoS Comput Biol 2020; 16:e1008030. [PMID: 32804924 PMCID: PMC7451993 DOI: 10.1371/journal.pcbi.1008030] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [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: 10/03/2019] [Revised: 08/27/2020] [Accepted: 06/08/2020] [Indexed: 11/24/2022] Open
Abstract
The human body generates a diverse set of high affinity antibodies, the soluble form of B cell receptors (BCRs), that bind to and neutralize invading pathogens. The natural development of BCRs must be understood in order to design vaccines for highly mutable pathogens such as influenza and HIV. BCR diversity is induced by naturally occurring combinatorial "V(D)J" rearrangement, mutation, and selection processes. Most current methods for BCR sequence analysis focus on separately modeling the above processes. Statistical phylogenetic methods are often used to model the mutational dynamics of BCR sequence data, but these techniques do not consider all the complexities associated with B cell diversification such as the V(D)J rearrangement process. In particular, standard phylogenetic approaches assume the DNA bases of the progenitor (or "naive") sequence arise independently and according to the same distribution, ignoring the complexities of V(D)J rearrangement. In this paper, we introduce a novel approach to Bayesian phylogenetic inference for BCR sequences that is based on a phylogenetic hidden Markov model (phylo-HMM). This technique not only integrates a naive rearrangement model with a phylogenetic model for BCR sequence evolution but also naturally accounts for uncertainty in all unobserved variables, including the phylogenetic tree, via posterior distribution sampling.
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MESH Headings
- Bayes Theorem
- Computational Biology
- Gene Rearrangement, B-Lymphocyte/genetics
- Humans
- Markov Chains
- Models, Genetic
- Phylogeny
- Receptors, Antigen, B-Cell/classification
- Receptors, Antigen, B-Cell/genetics
- Receptors, Antigen, B-Cell/immunology
- Sequence Analysis, DNA/methods
- Somatic Hypermutation, Immunoglobulin/genetics
- Vaccines
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Affiliation(s)
- Amrit Dhar
- Department of Statistics, University of Washington, Seattle, Washington, United States of America
- Computational Biology, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
| | - Duncan K. Ralph
- Computational Biology, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
| | - Vladimir N. Minin
- Department of Statistics, University of California, Irvine, California, United States of America
| | - Frederick A. Matsen
- Computational Biology, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
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13
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Chen H, Zhang Y, Ye AY, Du Z, Xu M, Lee CS, Hwang JK, Kyritsis N, Ba Z, Neuberg D, Littman DR, Alt FW. BCR selection and affinity maturation in Peyer's patch germinal centres. Nature 2020; 582:421-425. [PMID: 32499646 PMCID: PMC7478071 DOI: 10.1038/s41586-020-2262-4] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [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: 07/07/2018] [Accepted: 02/28/2020] [Indexed: 12/23/2022]
Abstract
The antigen-binding variable regions of the B cell receptor (BCR) and of antibodies are encoded by exons that are assembled in developing B cells by V(D)J recombination1. The BCR repertoires of primary B cells are vast owing to mechanisms that create diversity at the junctions of V(D)J gene segments that contribute to complementarity-determining region 3 (CDR3), the region that binds antigen1. Primary B cells undergo antigen-driven BCR affinity maturation through somatic hypermutation and cellular selection in germinal centres (GCs)2,3. Although most GCs are transient3, those in intestinal Peyer's patches (PPs)-which depend on the gut microbiota-are chronic4, and little is known about their BCR repertoires or patterns of somatic hypermutation. Here, using a high-throughput assay that analyses both V(D)J segment usage and somatic hypermutation profiles, we elucidate physiological BCR repertoires in mouse PP GCs. PP GCs from different mice expand public BCR clonotypes (clonotypes that are shared between many mice) that often have canonical CDR3s in the immunoglobulin heavy chain that, owing to junctional biases during V(D)J recombination, appear much more frequently than predicted in naive B cell repertoires. Some public clonotypes are dependent on the gut microbiota and encode antibodies that are reactive to bacterial glycans, whereas others are independent of gut bacteria. Transfer of faeces from specific-pathogen-free mice to germ-free mice restored germ-dependent clonotypes, directly implicating BCR selection. We identified somatic hypermutations that were recurrently selected in such public clonotypes, indicating that affinity maturation occurs in mouse PP GCs under homeostatic conditions. Thus, persistent gut antigens select recurrent BCR clonotypes to seed chronic PP GC responses.
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Affiliation(s)
- Huan Chen
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA, USA
- Department of Genetics, Harvard Medical School, Boston, MA, USA
- The Howard Hughes Medical Institute, Boston Children's Hospital, Boston, MA, USA
| | - Yuxiang Zhang
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA, USA
- Department of Genetics, Harvard Medical School, Boston, MA, USA
- The Howard Hughes Medical Institute, Boston Children's Hospital, Boston, MA, USA
| | - Adam Yongxin Ye
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA, USA
- Department of Genetics, Harvard Medical School, Boston, MA, USA
- The Howard Hughes Medical Institute, Boston Children's Hospital, Boston, MA, USA
| | - Zhou Du
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA, USA
- Department of Genetics, Harvard Medical School, Boston, MA, USA
- The Howard Hughes Medical Institute, Boston Children's Hospital, Boston, MA, USA
| | - Mo Xu
- Molecular Pathogenesis Program, The Kimmel Center for Biology and Medicine of the Skirball Institute, New York University School of Medicine, New York, NY, USA
- The Howard Hughes Medical Institute, New York University School of Medicine, New York, NY, USA
| | - Cheng-Sheng Lee
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA, USA
- Department of Genetics, Harvard Medical School, Boston, MA, USA
- The Howard Hughes Medical Institute, Boston Children's Hospital, Boston, MA, USA
| | - Joyce K Hwang
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA, USA
- Department of Genetics, Harvard Medical School, Boston, MA, USA
- The Howard Hughes Medical Institute, Boston Children's Hospital, Boston, MA, USA
| | - Nia Kyritsis
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA, USA
- Department of Genetics, Harvard Medical School, Boston, MA, USA
- The Howard Hughes Medical Institute, Boston Children's Hospital, Boston, MA, USA
| | - Zhaoqing Ba
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA, USA
- Department of Genetics, Harvard Medical School, Boston, MA, USA
- The Howard Hughes Medical Institute, Boston Children's Hospital, Boston, MA, USA
| | - Donna Neuberg
- Department of Data Sciences, Dana-Farber Cancer Institute, Boston, MA, USA
| | - Dan R Littman
- Molecular Pathogenesis Program, The Kimmel Center for Biology and Medicine of the Skirball Institute, New York University School of Medicine, New York, NY, USA
- The Howard Hughes Medical Institute, New York University School of Medicine, New York, NY, USA
| | - Frederick W Alt
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA, USA.
- Department of Genetics, Harvard Medical School, Boston, MA, USA.
- The Howard Hughes Medical Institute, Boston Children's Hospital, Boston, MA, USA.
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14
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Liu LD, Huang M, Dai P, Liu T, Fan S, Cheng X, Zhao Y, Yeap LS, Meng FL. Intrinsic Nucleotide Preference of Diversifying Base Editors Guides Antibody Ex Vivo Affinity Maturation. Cell Rep 2019; 25:884-892.e3. [PMID: 30355495 DOI: 10.1016/j.celrep.2018.09.090] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2018] [Revised: 09/13/2018] [Accepted: 09/27/2018] [Indexed: 12/27/2022] Open
Abstract
Base editors (BEs) are emerging tools used for precision correction or diversifying mutation. It provides a potential way to recreate somatic hypermutations (SHM) for generating high-affinity antibody, which is usually screened from antigen-challenged animal models or synthetic combinatorial libraries. By comparing somatic mutations in the same genomic context, we screened engineered deaminases and CRISPR-deaminase coupling approaches and updated diversifying base editors (DBEs) to generate SHM. The deaminase used in DBEs retains its intrinsic nucleotide preference and mutates cytidines at its preferred motifs. DBE with AID targets the same hotspots as physiological AID does in vivo, while DBE with other deaminases generates distinct mutation profiles from the same DNA substrate. Downstream DNA repair pathways further diversified the sequence, while Cas9-nickase restricted mutation spreading. Finally, application of DBE in an antibody display system achieved antibody affinity maturation ex vivo. Our findings provide insight of DBE working mechanism and an alternative antibody engineering approach.
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Affiliation(s)
- Liu Daisy Liu
- State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, 320 Yueyang Road, Shanghai 200031, China
| | - Min Huang
- State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, 320 Yueyang Road, Shanghai 200031, China
| | - Pengfei Dai
- State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, 320 Yueyang Road, Shanghai 200031, China
| | - Tingting Liu
- State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, 320 Yueyang Road, Shanghai 200031, China
| | - Shuangshuang Fan
- State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, 320 Yueyang Road, Shanghai 200031, China
| | - Xueqian Cheng
- State Key Laboratory of Agrobiotechnology, China Agricultural University, Beijing 100193, China
| | - Yaofeng Zhao
- State Key Laboratory of Agrobiotechnology, China Agricultural University, Beijing 100193, China
| | - Leng-Siew Yeap
- Shanghai Institute of Immunology, Department of Immunology and Microbiology, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China
| | - Fei-Long Meng
- State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, 320 Yueyang Road, Shanghai 200031, China.
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15
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Cho A, Caldara AL, Ran NA, Menne Z, Kauffman RC, Affer M, Llovet A, Norwood C, Scanlan A, Mantus G, Bradley B, Zimmer S, Schmidt T, Hertl M, Payne AS, Feldman R, Kowalczyk AP, Wrammert J. Single-Cell Analysis Suggests that Ongoing Affinity Maturation Drives the Emergence of Pemphigus Vulgaris Autoimmune Disease. Cell Rep 2019; 28:909-922.e6. [PMID: 31340153 PMCID: PMC6684256 DOI: 10.1016/j.celrep.2019.06.066] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [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: 02/10/2019] [Revised: 05/22/2019] [Accepted: 06/18/2019] [Indexed: 11/29/2022] Open
Abstract
Pemphigus vulgaris (PV) is an autoimmune disease characterized by blistering sores on skin and mucosal membranes, caused by autoantibodies primarily targeting the cellular adhesion protein, desmoglein-3 (Dsg3). To better understand how Dsg3-specific autoantibodies develop and cause disease in humans, we performed a cross-sectional study of PV patients before and after treatment to track relevant cellular responses underlying disease pathogenesis, and we provide an in-depth analysis of two patients by generating a panel of mAbs from single Dsg3-specific memory B cells (MBCs). Additionally, we analyzed a paired sample from one patient collected 15-months prior to disease diagnosis. We find that Dsg3-specific MBCs have an activated phenotype and show signs of ongoing affinity maturation and clonal selection. Monoclonal antibodies (mAbs) with pathogenic activity primarily target epitopes in the extracellular domains EC1 and EC2 of Dsg3, though they can also bind to the EC4 domain. Combining antibodies targeting different epitopes synergistically enhances in vitro pathogenicity.
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Affiliation(s)
- Alice Cho
- Department of Pediatrics, Division of Infectious Disease, Emory University School of Medicine, Atlanta, GA, USA; Emory Vaccine Center, Emory University School of Medicine, Atlanta, GA, USA
| | - Amber L Caldara
- Department of Cell Biology, Emory University, Atlanta, GA, USA; Department of Dermatology, Emory University School of Medicine, Atlanta, GA, USA
| | - Nina A Ran
- Department of Dermatology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Zach Menne
- Department of Pediatrics, Division of Infectious Disease, Emory University School of Medicine, Atlanta, GA, USA; Emory Vaccine Center, Emory University School of Medicine, Atlanta, GA, USA
| | - Robert C Kauffman
- Department of Pediatrics, Division of Infectious Disease, Emory University School of Medicine, Atlanta, GA, USA; Emory Vaccine Center, Emory University School of Medicine, Atlanta, GA, USA
| | - Maurizio Affer
- Department of Pediatrics, Division of Infectious Disease, Emory University School of Medicine, Atlanta, GA, USA; Emory Vaccine Center, Emory University School of Medicine, Atlanta, GA, USA
| | - Alexandra Llovet
- Department of Pediatrics, Division of Infectious Disease, Emory University School of Medicine, Atlanta, GA, USA; Emory Vaccine Center, Emory University School of Medicine, Atlanta, GA, USA
| | - Carson Norwood
- Department of Pediatrics, Division of Infectious Disease, Emory University School of Medicine, Atlanta, GA, USA; Emory Vaccine Center, Emory University School of Medicine, Atlanta, GA, USA
| | - Aaron Scanlan
- Department of Pediatrics, Division of Infectious Disease, Emory University School of Medicine, Atlanta, GA, USA; Emory Vaccine Center, Emory University School of Medicine, Atlanta, GA, USA
| | - Grace Mantus
- Department of Pediatrics, Division of Infectious Disease, Emory University School of Medicine, Atlanta, GA, USA; Emory Vaccine Center, Emory University School of Medicine, Atlanta, GA, USA
| | - Bridget Bradley
- Department of Dermatology, Emory University School of Medicine, Atlanta, GA, USA
| | - Stephanie Zimmer
- Department of Cell Biology, Emory University, Atlanta, GA, USA; Department of Dermatology, Emory University School of Medicine, Atlanta, GA, USA
| | - Thomas Schmidt
- Department of Dermatology and Allergology, Philipps-University, Marburg, Germany
| | - Michael Hertl
- Department of Dermatology and Allergology, Philipps-University, Marburg, Germany
| | - Aimee S Payne
- Department of Dermatology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Ron Feldman
- Department of Dermatology, Emory University School of Medicine, Atlanta, GA, USA
| | - Andrew P Kowalczyk
- Department of Cell Biology, Emory University, Atlanta, GA, USA; Department of Dermatology, Emory University School of Medicine, Atlanta, GA, USA
| | - Jens Wrammert
- Department of Pediatrics, Division of Infectious Disease, Emory University School of Medicine, Atlanta, GA, USA; Emory Vaccine Center, Emory University School of Medicine, Atlanta, GA, USA.
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16
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Muramatsu M, Kinoshita K, Fagarasan S, Yamada S, Shinkai Y, Honjo T. Pillars Article: Class Switch Recombination and Hypermutation Require Activation-Induced Cytidine Deaminase (AID), a Potential RNA Editing Enzyme. Cell. 2000. 102: 553-563. J Immunol 2018; 201:2530-2540. [PMID: 30348658] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
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17
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Abstract
The human immunoglobulin repertoire is a hugely diverse set of sequences that are formed by processes of gene rearrangement, heavy and light chain gene assortment, class switching and somatic hypermutation. Early B cell development produces diverse IgM and IgD B cell receptors on the B cell surface, resulting in a repertoire that can bind many foreign antigens but which has had self-reactive B cells removed. Later antigen-dependent development processes adjust the antigen affinity of the receptor by somatic hypermutation. The effector mechanism of the antibody is also adjusted, by switching the class of the antibody from IgM to one of seven other classes depending on the required function. There are many instances in human biology where positive and negative selection forces can act to shape the immunoglobulin repertoire and therefore repertoire analysis can provide useful information on infection control, vaccination efficacy, autoimmune diseases, and cancer. It can also be used to identify antigen-specific sequences that may be of use in therapeutics. The juxtaposition of lymphocyte development and numerical evaluation of immune repertoires has resulted in the growth of a new sub-speciality in immunology where immunologists and computer scientists/physicists collaborate to assess immune repertoires and develop models of immune action.
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Affiliation(s)
| | | | - Emma Sinclair
- Faculty of Health and Medical SciencesUniversity of SurreyGuildfordUK
| | - Alex Stewart
- Faculty of Health and Medical SciencesUniversity of SurreyGuildfordUK
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18
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Abstract
Probabilistic modeling is fundamental to the statistical analysis of complex data. In addition to forming a coherent description of the data-generating process, probabilistic models enable parameter inference about given datasets. This procedure is well developed in the Bayesian perspective, in which one infers probability distributions describing to what extent various possible parameters agree with the data. In this paper, we motivate and review probabilistic modeling for adaptive immune receptor repertoire data then describe progress and prospects for future work, from germline haplotyping to adaptive immune system deployment across tissues. The relevant quantities in immune sequence analysis include not only continuous parameters such as gene use frequency but also discrete objects such as B-cell clusters and lineages. Throughout this review, we unravel the many opportunities for probabilistic modeling in adaptive immune receptor analysis, including settings for which the Bayesian approach holds substantial promise (especially if one is optimistic about new computational methods). From our perspective, the greatest prospects for progress in probabilistic modeling for repertoires concern ancestral sequence estimation for B-cell receptor lineages, including uncertainty from germline genotype, rearrangement, and lineage development.
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Affiliation(s)
- Branden Olson
- Computational Biology Program Fred Hutchinson Cancer Research Center, 1100 Fairview Ave. N., Mail stop: M1-B514 Seattle, WA 98109-1024 phone: +1 206 667 7318
| | - Frederick A. Matsen
- Computational Biology Program Fred Hutchinson Cancer Research Center, 1100 Fairview Ave. N., Mail stop: M1-B514 Seattle, WA 98109-1024 phone: +1 206 667 7318
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19
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Klymenko T, Bloehdorn J, Bahlo J, Robrecht S, Akylzhanova G, Cox K, Estenfelder S, Wang J, Edelmann J, Strefford JC, Wojdacz TK, Fischer K, Hallek M, Stilgenbauer S, Cragg M, Gribben J, Braun A. Lamin B1 regulates somatic mutations and progression of B-cell malignancies. Leukemia 2018; 32:364-375. [PMID: 28804121 PMCID: PMC5808072 DOI: 10.1038/leu.2017.255] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [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: 01/23/2017] [Revised: 07/07/2017] [Accepted: 07/31/2017] [Indexed: 12/24/2022]
Abstract
Somatic hypermutation (SHM) is a pivotal process in adaptive immunity that occurs in the germinal centre and allows B cells to change their primary DNA sequence and diversify their antigen receptors. Here, we report that genome binding of Lamin B1, a component of the nuclear envelope involved in epigenetic chromatin regulation, is reduced during B-cell activation and formation of lymphoid germinal centres. Chromatin immunoprecipitation-Seq analysis showed that kappa and heavy variable immunoglobulin domains were released from the Lamin B1 suppressive environment when SHM was induced in B cells. RNA interference-mediated reduction of Lamin B1 resulted in spontaneous SHM as well as kappa-light chain aberrant surface expression. Finally, Lamin B1 expression level correlated with progression-free and overall survival in chronic lymphocytic leukaemia, and was strongly involved in the transformation of follicular lymphoma. In summary, here we report that Lamin B1 is a negative epigenetic regulator of SHM in normal B-cells and a 'mutational gatekeeper', suppressing the aberrant mutations that drive lymphoid malignancy.
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MESH Headings
- B-Lymphocytes/pathology
- Cell Line, Tumor
- Chromatin Immunoprecipitation/methods
- Disease Progression
- Humans
- Immunoglobulin Heavy Chains/genetics
- Immunoglobulin Variable Region/genetics
- Lamin Type B/genetics
- Leukemia, Lymphocytic, Chronic, B-Cell/genetics
- Leukemia, Lymphocytic, Chronic, B-Cell/pathology
- Lymphoma, Follicular/genetics
- Lymphoma, Follicular/pathology
- Somatic Hypermutation, Immunoglobulin/genetics
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Affiliation(s)
- T Klymenko
- Centre for Haemato-Oncology, Barts Cancer Institute, Queen Mary University, London, UK
| | - J Bloehdorn
- Department of Internal Medicine III, University of Ulm, Ulm, Germany
| | - J Bahlo
- Department I of Internal Medicine, Center for Integrated Oncology Cologne, University Hospital of Cologne, Cologne, Germany
| | - S Robrecht
- Department I of Internal Medicine, Center for Integrated Oncology Cologne, University Hospital of Cologne, Cologne, Germany
| | - G Akylzhanova
- Centre for Haemato-Oncology, Barts Cancer Institute, Queen Mary University, London, UK
| | - K Cox
- Academic Unit of Cancer Sciences, Faculty of Medicine, Cancer Research UK Centre and Experimental Cancer Medicine Centre, University of Southampton, Southampton, UK
| | - S Estenfelder
- Department of Internal Medicine III, University of Ulm, Ulm, Germany
| | - J Wang
- Centre for Haemato-Oncology, Barts Cancer Institute, Queen Mary University, London, UK
| | - J Edelmann
- Centre for Haemato-Oncology, Barts Cancer Institute, Queen Mary University, London, UK
| | - J C Strefford
- Academic Unit of Cancer Sciences, Faculty of Medicine, Cancer Research UK Centre and Experimental Cancer Medicine Centre, University of Southampton, Southampton, UK
| | - T K Wojdacz
- Academic Unit of Cancer Sciences, Faculty of Medicine, Cancer Research UK Centre and Experimental Cancer Medicine Centre, University of Southampton, Southampton, UK
- Aarhus Institute of Advanced Studies, Aarhus University, Aarhus, Denmark
| | - K Fischer
- Department I of Internal Medicine, Center for Integrated Oncology Cologne, University Hospital of Cologne, Cologne, Germany
| | - M Hallek
- Department I of Internal Medicine, Center for Integrated Oncology Cologne, University Hospital of Cologne, Cologne, Germany
| | - S Stilgenbauer
- Department of Internal Medicine III, University of Ulm, Ulm, Germany
| | - M Cragg
- Academic Unit of Cancer Sciences, Faculty of Medicine, Cancer Research UK Centre and Experimental Cancer Medicine Centre, University of Southampton, Southampton, UK
| | - J Gribben
- Centre for Haemato-Oncology, Barts Cancer Institute, Queen Mary University, London, UK
| | - A Braun
- Centre for Haemato-Oncology, Barts Cancer Institute, Queen Mary University, London, UK
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20
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Bahjat M, Guikema JEJ. The Complex Interplay between DNA Injury and Repair in Enzymatically Induced Mutagenesis and DNA Damage in B Lymphocytes. Int J Mol Sci 2017; 18:ijms18091876. [PMID: 28867784 PMCID: PMC5618525 DOI: 10.3390/ijms18091876] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2017] [Revised: 08/24/2017] [Accepted: 08/29/2017] [Indexed: 11/25/2022] Open
Abstract
Lymphocytes are endowed with unique and specialized enzymatic mutagenic properties that allow them to diversify their antigen receptors, which are crucial sensors for pathogens and mediators of adaptive immunity. During lymphocyte development, the antigen receptors expressed by B and T lymphocytes are assembled in an antigen-independent fashion by ordered variable gene segment recombinations (V(D)J recombination), which is a highly ordered and regulated process that requires the recombination activating gene products 1 & 2 (RAG1, RAG2). Upon activation by antigen, B lymphocytes undergo additional diversifications of their immunoglobulin B-cell receptors. Enzymatically induced somatic hypermutation (SHM) and immunoglobulin class switch recombination (CSR) improves the affinity for antigen and shape the effector function of the humoral immune response, respectively. The activation-induced cytidine deaminase (AID) enzyme is crucial for both SHM and CSR. These processes have evolved to both utilize as well as evade different DNA repair and DNA damage response pathways. The delicate balance between enzymatic mutagenesis and DNA repair is crucial for effective immune responses and the maintenance of genomic integrity. Not surprisingly, disturbances in this balance are at the basis of lymphoid malignancies by provoking the formation of oncogenic mutations and chromosomal aberrations. In this review, we discuss recent mechanistic insight into the regulation of RAG1/2 and AID expression and activity in lymphocytes and the complex interplay between these mutagenic enzymes and DNA repair and DNA damage response pathways, focusing on the base excision repair and mismatch repair pathways. We discuss how disturbances of this interplay induce genomic instability and contribute to oncogenesis.
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Affiliation(s)
- Mahnoush Bahjat
- Department of Pathology, Academic Medical Center, University of Amsterdam; Lymphoma and Myeloma Center Amsterdam (LYMMCARE), Amsterdam 1105 AZ, The Netherlands.
| | - Jeroen E J Guikema
- Department of Pathology, Academic Medical Center, University of Amsterdam; Lymphoma and Myeloma Center Amsterdam (LYMMCARE), Amsterdam 1105 AZ, The Netherlands.
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21
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Reed JH, Gorny MK, Li L, Cardozo T, Buyon JP, Clancy RM. Ro52 autoantibodies arise from self-reactive progenitors in a mother of a child with neonatal lupus. J Autoimmun 2017; 79:99-104. [PMID: 28118945 DOI: 10.1016/j.jaut.2017.01.004] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [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: 11/29/2016] [Revised: 01/04/2017] [Accepted: 01/16/2017] [Indexed: 01/06/2023]
Abstract
The detection of cardiac conduction defects in an 18-24 week old foetus in the absence of structural abnormalities predicts with near certainty the presence of autoantibodies against 60kD and 52kD SSA/Ro in the mother regardless of her health status. Previous studies have emphasized these autoantibodies as key mediators of tissue injury. The aim of this study was to focus on the anti-Ro52 response to determine whether these autoantibodies originate from progenitors that are inherently self-reactive or from B-cells that acquire self-reactivity during an immune response. We traced the evolution of two anti-Ro52 autoantibodies isolated from circulating IgG1-switched B-cells from an asymptomatic mother of a child with third degree congenital heart block. The autoantibodies were expressed as their immune form and as pre-immune ancestors by reverting somatic mutations to germline sequence. The reactivity of pre-immune and immune antibodies for Ro52, Ro60, La and DNA was measured. Both anti-Ro52 autoantibodies exhibited a low frequency of somatic mutations (3-4%) and utilised the same heavy and light chain genes but represented distinct clones based on differing complementarity determining region sequences. Pre- and post-immune antibodies showed specific binding to Ro52 with no measurable reactivity for other autoantigens. Ro52 binding was higher for immune antibodies compared to pre-immune counterparts demonstrating that autoreactivity was enhanced by affinity maturation. These data indicate that Ro52 reactivity is an intrinsic property of the germline antibody repertoire in a mother with a pathogenic antibody defined by cardiac injury in her offspring, and implies defects in both central and peripheral tolerance mechanisms.
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Affiliation(s)
- Joanne H Reed
- Dept. Immunology, Garvan Institute of Medical Research, Sydney, Australia.
| | - Miroslaw K Gorny
- Dept. Pathology, New York University School of Medicine, New York, USA
| | - Liuzhe Li
- Dept. Pathology, New York University School of Medicine, New York, USA
| | - Timothy Cardozo
- Dept. Pharmacology, New York University School of Medicine, New York, USA
| | - Jill P Buyon
- Dept. Medicine, Division of Rheumatology, New York University School of Medicine, New York, USA
| | - Robert M Clancy
- Dept. Medicine, Division of Rheumatology, New York University School of Medicine, New York, USA
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22
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Walther S, Tietze M, Czerny CP, König S, Diesterbeck US. Development of a Bioinformatics Framework for the Detection of Gene Conversion and the Analysis of Combinatorial Diversity in Immunoglobulin Heavy Chains in Four Cattle Breeds. PLoS One 2016; 11:e0164567. [PMID: 27828971 PMCID: PMC5102495 DOI: 10.1371/journal.pone.0164567] [Citation(s) in RCA: 8] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Accepted: 09/06/2016] [Indexed: 02/06/2023] Open
Abstract
We have developed a new bioinformatics framework for the analysis of rearranged bovine heavy chain immunoglobulin (Ig) variable regions by combining and refining widely used alignment algorithms. This bioinformatics framework allowed us to investigate alignments of heavy chain framework regions (FRHs) and the separate alignments of FRHs and heavy chain complementarity determining regions (CDRHs) to determine their germline origin in the four cattle breeds Aubrac, German Black Pied, German Simmental, and Holstein Friesian. Now it is also possible to specifically analyze Ig heavy chains possessing exceptionally long CDR3Hs. In order to gain more insight into breed specific differences in Ig combinatorial diversity, somatic hypermutations and putative gene conversions of IgG, we compared the dominantly transcribed variable (IGHV), diversity (IGHD), and joining (IGHJ) segments and their recombination in the four cattle breeds. The analysis revealed the use of 15 different IGHV segments, 21 IGHD segments, and two IGHJ segments with significant different transcription levels within the breeds. Furthermore, there are preferred rearrangements within the three groups of CDR3H lengths. In the sequences of group 2 (CDR3H lengths (L) of 11–47 amino acid residues (aa)) a higher number of recombination was observed than in sequences of group 1 (L≤10 aa) and 3 (L≥48 aa). The combinatorial diversity of germline IGHV, IGHD, and IGHJ-segments revealed 162 rearrangements that were significantly different. The few preferably rearranged gene segments within group 3 CDR3H regions may indicate specialized antibodies because this length is unique in cattle. The most important finding of this study, which was enabled by using the bioinformatics framework, is the discovery of strong evidence for gene conversion as a rare event using pseudogenes fulfilling all definitions for this particular diversification mechanism.
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Affiliation(s)
- Stefanie Walther
- Department of Animal Sciences, Institute of Veterinary Medicine, Division of Microbiology and Animal Hygiene, Faculty of Agricultural Sciences, Georg-August University Goettingen, Goettingen, Germany
| | - Manfred Tietze
- Department of Animal Breeding, University of Kassel, Witzenhausen, Germany
| | - Claus-Peter Czerny
- Department of Animal Sciences, Institute of Veterinary Medicine, Division of Microbiology and Animal Hygiene, Faculty of Agricultural Sciences, Georg-August University Goettingen, Goettingen, Germany
| | - Sven König
- Department of Animal Breeding, University of Kassel, Witzenhausen, Germany
| | - Ulrike S. Diesterbeck
- Department of Animal Sciences, Institute of Veterinary Medicine, Division of Microbiology and Animal Hygiene, Faculty of Agricultural Sciences, Georg-August University Goettingen, Goettingen, Germany
- * E-mail:
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Zanotti KJ, Gearhart PJ. Antibody diversification caused by disrupted mismatch repair and promiscuous DNA polymerases. DNA Repair (Amst) 2016; 38:110-116. [PMID: 26719140 PMCID: PMC4740194 DOI: 10.1016/j.dnarep.2015.11.011] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [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: 09/03/2015] [Accepted: 11/30/2015] [Indexed: 10/25/2022]
Abstract
The enzyme activation-induced deaminase (AID) targets the immunoglobulin loci in activated B cells and creates DNA mutations in the antigen-binding variable region and DNA breaks in the switch region through processes known, respectively, as somatic hypermutation and class switch recombination. AID deaminates cytosine to uracil in DNA to create a U:G mismatch. During somatic hypermutation, the MutSα complex binds to the mismatch, and the error-prone DNA polymerase η generates mutations at A and T bases. During class switch recombination, both MutSα and MutLα complexes bind to the mismatch, resulting in double-strand break formation and end-joining. This review is centered on the mechanisms of how the MMR pathway is commandeered by B cells to generate antibody diversity.
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Affiliation(s)
- Kimberly J Zanotti
- Laboratory of Molecular Biology and Immunology, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA
| | - Patricia J Gearhart
- Laboratory of Molecular Biology and Immunology, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA.
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Guo K, Halemano K, Schmitt K, Katuwal M, Wang Y, Harper MS, Heilman KJ, Kuwata T, Stephens EB, Santiago ML. Immunoglobulin VH gene diversity and somatic hypermutation during SIV infection of rhesus macaques. Immunogenetics 2015; 67:355-70. [PMID: 25994147 DOI: 10.1007/s00251-015-0844-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [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: 03/30/2015] [Accepted: 04/30/2015] [Indexed: 01/12/2023]
Abstract
B cell functional defects are associated with delayed neutralizing antibody development in pathogenic lentivirus infections. However, the timeframe for alterations in the antibody repertoire and somatic hypermutation (SHM) remains unclear. Here, we utilized the SIV/rhesus macaque (RM) model to investigate the dynamics of immunoglobulin V(H) gene diversity and SHM following infection. Three RMs were infected with SIVmac239, and V(H)1, V(H)3, and V(H)4 genes were amplified from peripheral blood at 0, 2, 6, 24, and 36 weeks postinfection for next-generation sequencing. Analysis of over 3.8 million sequences against currently available RM germline V(H) genes revealed a highly biased V(H) gene repertoire in outbred RMs. SIV infection did not significantly perturb the predominant IgG1 response, but overall immunoglobulin SHM declined during the course of SIV infection. Moreover, SHM at the AID deamination hotspot, WRC, rapidly decreased and was suppressed throughout SIV infection. In contrast, a transient increase in mutations at the APOBEC3G deamination hotspot, CCC, coincided with a spike in APOBEC3G expression during acute SIV infection. The results outline a timetable for altered V(H) gene repertoire and IgG SHM in the SIV/RM model and suggest a burst of APOBEC3G-mediated antibody SHM during acute SIV infection.
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Affiliation(s)
- Kejun Guo
- Departments of Medicine, Immunology and Microbiology, University of Colorado Denver, Aurora, CO, 80045, USA
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25
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Spence JM, Abumoussa A, Spence JP, Burack WR. Intraclonal diversity in follicular lymphoma analyzed by quantitative ultradeep sequencing of noncoding regions. J Immunol 2014; 193:4888-94. [PMID: 25311808 PMCID: PMC4225181 DOI: 10.4049/jimmunol.1401699] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Cancers are characterized by genomic instability, and the resulting intraclonal diversity is a prerequisite for tumor evolution. Therefore, metrics of tumor heterogeneity may prove to be clinically meaningful. Intraclonal heterogeneity in follicular lymphoma (FL) is apparent from studies of somatic hypermutation (SHM) caused by activation-induced deaminase (AID) in IGH. Aberrant SHM (aSHM), defined as AID activity outside of the IG loci, predominantly targets noncoding regions causing numerous "passenger" mutations, but it has the potential to generate rare significant "driver" mutations. The quantitative relationship between SHM and aSHM has not been defined. To measure SHM and aSHM, ultradeep sequencing (>20,000-fold coverage) was performed on IGH (~1650 nt) and nine other noncoding regions potentially targeted by AID (combined 9411 nt), including the 5' untranslated region of BCL2. Single-nucleotide variants (SNVs) were found in 12/12 FL specimens (median 136 SHMs and 53 aSHMs). The aSHM SNVs were associated with AID motifs (p < 0.0001). The number of SNVs at BCL2 varied widely among specimens and correlated with the number of SNVs at eight other potential aSHM sites. In contrast, SHM at IGH was not predictive of aSHM. Tumor heterogeneity is apparent from SNVs at low variant allele frequencies; the relative number of SNVs with variable allele frequency < 5% varied with clinical grade, indicating that tumor heterogeneity based on aSHM reflects a clinically meaningful parameter. These data suggest that genome-wide aSHM may be estimated from aSHM of BCL2 but not SHM of IGH. The results demonstrate a practical approach to the quantification of intratumoral genetic heterogeneity for clinical specimens.
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MESH Headings
- 5' Untranslated Regions
- Alleles
- B-Lymphocytes/immunology
- B-Lymphocytes/pathology
- Chromosomes, Human, Pair 14
- Chromosomes, Human, Pair 18
- Clone Cells
- Cytidine Deaminase/genetics
- Cytidine Deaminase/immunology
- Gene Expression
- Gene Frequency
- Genes, bcl-2/genetics
- Genes, bcl-2/immunology
- Genetic Loci
- Genome, Human
- Genomic Instability
- High-Throughput Nucleotide Sequencing
- Humans
- Lymphoma, Follicular/genetics
- Lymphoma, Follicular/immunology
- Lymphoma, Follicular/pathology
- Polymorphism, Single Nucleotide
- Somatic Hypermutation, Immunoglobulin/genetics
- Somatic Hypermutation, Immunoglobulin/immunology
- Translocation, Genetic
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Affiliation(s)
- Janice M Spence
- Department of Pathology and Laboratory Medicine, University of Rochester Medical Center, Rochester NY 14642
| | - Andrew Abumoussa
- Department of Computer Science, University of Rochester, Rochester NY 14642; and
| | | | - W Richard Burack
- Department of Pathology and Laboratory Medicine, University of Rochester Medical Center, Rochester NY 14642;
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Briney BS, Willis JR, Finn JA, McKinney BA, Crowe JE. Tissue-specific expressed antibody variable gene repertoires. PLoS One 2014; 9:e100839. [PMID: 24956460 PMCID: PMC4067404 DOI: 10.1371/journal.pone.0100839] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2013] [Accepted: 05/30/2014] [Indexed: 01/05/2023] Open
Abstract
Recent developments in genetic technologies allow deep analysis of the sequence diversity of immune repertoires, but little work has been reported on the architecture of immune repertoires in mucosal tissues. Antibodies are the key to prevention of infections at the mucosal surface, but it is currently unclear whether the B cell repertoire at mucosal surfaces reflects the dominant antibodies found in the systemic compartment or whether mucosal tissues harbor unique repertoires. We examined the expressed antibody variable gene repertoires from 10 different human tissues using RNA samples derived from a large number of individuals. The results revealed that mucosal tissues such as stomach, intestine and lung possess unique antibody gene repertoires that differed substantially from those found in lymphoid tissues or peripheral blood. Mutation frequency analysis of mucosal tissue repertoires revealed that they were highly mutated, with little evidence for the presence of naïve B cells, in contrast to blood. Mucosal tissue repertoires possessed longer heavy chain complementarity determining region 3 loops than lymphoid tissue repertoires. We also noted a large increase in frequency of both insertions and deletions in the small intestine antibody repertoire. These data suggest that mucosal immune repertoires are distinct in many ways from the systemic compartment.
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Affiliation(s)
- Bryan S. Briney
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
| | - Jordan R. Willis
- The Chemical and Physical Biology Program, Vanderbilt University, Nashville, Tennessee, United States of America
| | - Jessica A. Finn
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
| | - Brett A. McKinney
- Tandy School of Computer Science and Department of Mathematics, University of Tulsa, Tulsa, Oklahoma, United States of America
| | - James E. Crowe
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
- The Vanderbilt Vaccine Center, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
- * E-mail:
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Stamatopoulos K, Belessi C, Papadaki T, Stavroyianni N, Hadzidimitriou A, Kosmas C, Laoutaris N, Fassas A, Anagnostopoulos A. Somatic Hypermutation Patterns in Germinal Center B Cell Malignancies. Hematology 2013; 8:319-28. [PMID: 14530174 DOI: 10.1080/10245330310001612143] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Affiliation(s)
- Kostas Stamatopoulos
- Hematology Department and HCT Unit, G Papanicolaou Hospital, Thessaloniki, Greece.
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Abstract
Host genetic factors may play an effective role on the human immunodeficiency virus (HIV) pathogenesis. APOBEC3 (apolipoprotein B mRNA editing enzyme catalytic polypeptide like-3) proteins are cellular antiviral proteins which inhibits HIV replication in the absence of vif (virion infectivity factor). In this study, we aimed to determine the APOBEC 3G/F hypermutations in HIV-1 strains isolated in Turkey. A total of 515 HIV-1 infected patients between June 2009 - February 2012 were included in the study. Three hundred ninety four cases were newly diagnosed antiretroviral-naive patients [349 male, 45 female; median age (range): 37.1 (2-69) years; median CD4+ T-cell count (range): 340 (1-1660) mm3; median HIV-RNA load (range): 5.76 + E5 (8.7 + E2-9.4 + E6) IU/ml] and 121 were under HAART therapy [99 male, 22 female; median age (range): 40.7 (20-70) years; median CD4+ T-cell count (range): 195 (6-720) mm3; median HIV-RNA load (range): 5.4 + E5 (1.37 + E3-1.07 + E7) IU/ml]. APOBEC 3G/F hypermutations in HIV-1 pol sequences (reverse transcriptase; codons 41-238 and protease; codons 1-99) analysed by nested RT-PCR and direct sequencing techniques. APOBEC 3G/F hypermutations have been determined by using of HIVdb-Stanford algorithm. The prevalence of overall APOBEC 3G/F hypermutations was 2.5% (13/515) in HIV-1 pol gene sequences in study group, and the rates were 2% (8/394) and 4.1% (5/121) in antiretroviral naive and treatment groups, respectively. However, the location and marker hypermutations of determined APOBEC in the HIV-1 pol gene sequences were RT and 3G in the Turkish patients. The hypermutated HIV-1 strains identified in HIV-1 infected patients may facilitate our understanding the nature and the consequences of HIV-1 infections. Moreover, investigations of the motif and frequency of APOBEC 3G/F hypermutations in HIV-1 proviral DNA samples and understanding their relationships with HIV-1 subtypes in Turkish patients would be beneficial.
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Affiliation(s)
- Murat Sayan
- Kocaeli University Medical Faculty Hospital, Central Laboratory, PCR Unit, Kocaeli, Turkey.
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30
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Butler JE, Sun X, Wertz N, Vincent AL, Zanella EL, Lager KM. Antibody repertoire development in fetal and neonatal piglets. XVI. Influenza stimulates adaptive immunity, class switch and diversification of the IgG repertoire encoded by downstream Cγ genes. Immunology 2013; 138:134-44. [PMID: 23320646 PMCID: PMC3575766 DOI: 10.1111/imm.12018] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2012] [Revised: 09/27/2012] [Accepted: 10/02/2012] [Indexed: 12/15/2022] Open
Abstract
Infection of germ-free isolator piglets with swine influenza (S-FLU) that generates dsRNA during replication causes elevation of immunoglobulins in serum and bronchoalveolar lavage, a very weak response to trinitrophenyl conjugates but an immune response to S-FLU. The increased immunoglobulin levels result mainly from the polyclonal activation of B cells during the infection, but model antigen exposure may contribute. The 10-fold increase in local and serum IgG accompanies a 10-fold decrease in the transcription of IgG3 in the tracheal-bronchial lymph nodes and in the ileal Peyer's patches. Infection results in class switch recombination to downstream Cγ genes, which diversify their repertoire; both features are diagnostic of adaptive immunity. Meanwhile the repertoires of IgM and IgG3 remain undiversified suggesting that they encode innate, natural antibodies. Whereas IgG3 may play an initial protective role, antibodies encoded by downstream Cγ genes with diversified repertoires are predicted to be most important in long-term protection against S-FLU.
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Affiliation(s)
- John E Butler
- Department of Microbiology, Carver College of Medicine, Iowa City, IA 52240, USA.
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31
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Hu Y, Ericsson I, Torseth K, Methot SP, Sundheim O, Liabakk NB, Slupphaug G, Di Noia JM, Krokan HE, Kavli B. A combined nuclear and nucleolar localization motif in activation-induced cytidine deaminase (AID) controls immunoglobulin class switching. J Mol Biol 2013; 425:424-43. [PMID: 23183374 DOI: 10.1016/j.jmb.2012.11.026] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [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] [Received: 10/10/2012] [Revised: 11/13/2012] [Accepted: 11/15/2012] [Indexed: 11/18/2022]
Abstract
Activation-induced cytidine deaminase (AID) is a DNA mutator enzyme essential for adaptive immunity. AID initiates somatic hypermutation and class switch recombination (CSR) by deaminating cytosine to uracil in specific immunoglobulin (Ig) gene regions. However, other loci, including cancer-related genes, are also targeted. Thus, tight regulation of AID is crucial to balance immunity versus disease such as cancer. AID is regulated by several mechanisms including nucleocytoplasmic shuttling. Here we have studied nuclear import kinetics and subnuclear trafficking of AID in live cells and characterized in detail its nuclear localization signal. Importantly, we find that the nuclear localization signal motif also directs AID to nucleoli where it colocalizes with its interaction partner, catenin-β-like 1 (CTNNBL1), and physically associates with nucleolin and nucleophosmin. Moreover, we demonstrate that release of AID from nucleoli is dependent on its C-terminal motif. Finally, we find that CSR efficiency correlates strongly with the arithmetic product of AID nuclear import rate and DNA deamination activity. Our findings suggest that directional nucleolar transit is important for the physiological function of AID and demonstrate that nuclear/nucleolar import and DNA cytosine deamination together define the biological activity of AID. This is the first study on subnuclear trafficking of AID and demonstrates a new level in its complex regulation. In addition, our results resolve the problem related to dissociation of deamination activity and CSR activity of AID mutants.
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Affiliation(s)
- Yi Hu
- Department of Cancer Research and Molecular Medicine, Norwegian University of Science and Technology, N-7491 Trondheim, Norway
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McConnell AD, Do M, Neben TY, Spasojevic V, MacLaren J, Chen AP, Altobell L, Macomber JL, Berkebile AD, Horlick RA, Bowers PM, King DJ. High affinity humanized antibodies without making hybridomas; immunization paired with mammalian cell display and in vitro somatic hypermutation. PLoS One 2012; 7:e49458. [PMID: 23166676 PMCID: PMC3498135 DOI: 10.1371/journal.pone.0049458] [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] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2012] [Accepted: 10/09/2012] [Indexed: 01/15/2023] Open
Abstract
A method has been developed for the rapid generation of high-affinity humanized antibodies from immunized animals without the need to make conventional hybridomas. Rearranged IgH D(J) regions were amplified from the spleen and lymph tissue of mice immunized with the human complement protein C5, fused with a limited repertoire of human germline heavy chain V-genes to form intact humanized heavy chains, and paired with a human light chain library. Completed heavy and light chains were assembled for mammalian cell surface display and transfected into HEK 293 cells co-expressing activation-induced cytidine deaminase (AID). Numerous clones were isolated by fluorescence-activated cell sorting, and affinity maturation, initiated by AID, resulted in the rapid evolution of high affinity, functional antibodies. This approach enables the efficient sampling of an immune repertoire and the direct selection and maturation of high-affinity, humanized IgGs.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | - Peter M. Bowers
- AnaptysBio, Inc., San Diego, California, United States of America
- * E-mail:
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Alamyar E, Duroux P, Lefranc MP, Giudicelli V. IMGT(®) tools for the nucleotide analysis of immunoglobulin (IG) and T cell receptor (TR) V-(D)-J repertoires, polymorphisms, and IG mutations: IMGT/V-QUEST and IMGT/HighV-QUEST for NGS. Methods Mol Biol 2012; 882:569-604. [PMID: 22665256 DOI: 10.1007/978-1-61779-842-9_32] [Citation(s) in RCA: 343] [Impact Index Per Article: 28.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
IMGT/V-QUEST is the highly customized and integrated online IMGT(®) tool for the standardized analysis of the immunoglobulin (IG) or antibody and T cell receptor (TR) rearranged nucleotide sequences. The analysis of these antigen receptors represents a crucial challenge for the study of the adaptive immune response in normal and disease-related situations. The expressed IG and TR repertoires represent a potential of 10(12) IG and 10(12) TR per individual. This huge diversity results from mechanisms that occur at the DNA level during the IG and TR molecular synthesis. These mechanisms include the combinatorial rearrangements of the variable (V), diversity (D) and joining (J) genes, the N-diversity (deletion and addition at random of nucleotides during the V-(D)-J rearrangement) and, for IG, somatic hypermutations. IMGT/V-QUEST identifies the V, D, J genes and alleles by alignment with the germline IG and TR gene and allele sequences of the IMGT reference directory. The tool describes the V-REGION mutations and identifies the hot spot positions in the closest germline V gene. IMGT/V-QUEST integrates IMGT/JunctionAnalysis for a detailed analysis of the V-J and V-D-J junctions and IMGT/Automat for a complete annotation of the sequences and also provides IMGT Collier de Perles. IMGT/HighV-QUEST, the high-throughput version of IMGT/V-QUEST, implemented to answer the needs of deep sequencing data analysis from Next Generation Sequencing (NGS), allows the analysis of thousands of IG and TR sequences in a single run. IMGT/V-QUEST and IMGT/HighV-QUEST are available at the IMGT(®) Home page, http://www.imgt.org.
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Affiliation(s)
- Eltaf Alamyar
- IMGT®, the International ImMunoGeneTics Information System®, Université Montpellier 2, Laboratoire d'ImmunoGénétique Moléculaire (LIGM), Institut de Génétique Humaine (IGH), UPR CNRS 1142, Montpellier, France
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Sebastián E, Alcoceba M, Balanzategui A, Marín L, Montes-Moreno S, Flores T, González D, Sarasquete ME, Chillón MC, Puig N, Corral R, Pardal E, Martín A, González-Barca E, Caballero MD, San Miguel JF, García-Sanz R, González M. Molecular characterization of immunoglobulin gene rearrangements in diffuse large B-cell lymphoma: antigen-driven origin and IGHV4-34 as a particular subgroup of the non-GCB subtype. Am J Pathol 2012; 181:1879-88. [PMID: 22982190 DOI: 10.1016/j.ajpath.2012.07.028] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2012] [Revised: 07/19/2012] [Accepted: 07/30/2012] [Indexed: 01/05/2023]
Abstract
The pathogenesis of diffuse large B-cell lymphoma (DLBCL) remains partially unknown. The analysis of the B-cell receptor of the malignant cells could contribute to a better understanding of the DLBCL biology. We studied the molecular features of the immunoglobulin heavy chain (IGH) rearrangements in 165 patients diagnosed with DLBCL not otherwise specified. Clonal IGH rearrangements were amplified according to the BIOMED-2 protocol and PCR products were sequenced directly. We also analyzed the criteria for stereotyped patterns in all complete IGHV-IGHD-IGHJ (V-D-J) sequences. Complete V-D-J rearrangements were identified in 130 of 165 patients. Most cases (89%) were highly mutated, but 12 sequences were truly unmutated or minimally mutated. Three genes, IGHV4-34, IGHV3-23, and IGHV4-39, accounted for one third of the whole cohort, including an overrepresentation of IGHV4-34 (15.5% overall). Interestingly, all IGHV4-34 rearrangements and all unmutated sequences belonged to the nongerminal center B-cell-like (non-GCB) subtype. Overall, we found three cases following the current criteria for stereotyped heavy chain VH CDR3 sequences, two of them belonging to subsets previously described in CLL. IGHV gene repertoire is remarkably biased, implying an antigen-driven origin in DLBCL. The particular features in the sequence of the immunoglobulins suggest the existence of particular subgroups within the non-GCB subtype.
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MESH Headings
- Adolescent
- Adult
- Aged
- Aged, 80 and over
- Amino Acid Sequence
- Amino Acids/genetics
- Antigens, Neoplasm/immunology
- Clone Cells
- Complementarity Determining Regions/chemistry
- Complementarity Determining Regions/genetics
- Female
- Gene Rearrangement, B-Lymphocyte, Heavy Chain/genetics
- Germinal Center/immunology
- Humans
- Immunoglobulin Heavy Chains/genetics
- Immunoglobulin Variable Region/genetics
- Immunohistochemistry
- Lymphoma, Large B-Cell, Diffuse/classification
- Lymphoma, Large B-Cell, Diffuse/diagnosis
- Lymphoma, Large B-Cell, Diffuse/genetics
- Lymphoma, Large B-Cell, Diffuse/immunology
- Male
- Middle Aged
- Molecular Sequence Data
- Mutation/genetics
- Somatic Hypermutation, Immunoglobulin/genetics
- Somatic Hypermutation, Immunoglobulin/immunology
- V(D)J Recombination/genetics
- V(D)J Recombination/immunology
- Young Adult
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Affiliation(s)
- Elena Sebastián
- Department of Hematology, University Hospital of Salamanca, Spain
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35
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Jiang Y, Soong TD, Wang L, Melnick AM, Elemento O. Genome-wide detection of genes targeted by non-Ig somatic hypermutation in lymphoma. PLoS One 2012; 7:e40332. [PMID: 22808135 PMCID: PMC3395700 DOI: 10.1371/journal.pone.0040332] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [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: 02/22/2012] [Accepted: 06/07/2012] [Indexed: 12/29/2022] Open
Abstract
The processes of somatic hypermutation (SHM) and class switch recombination introduced by activation-induced cytosine deaminase (AICDA) at the Immunoglobulin (Ig) loci are key steps for creating a pool of diversified antibodies in germinal center B cells (GCBs). Unfortunately, AICDA can also accidentally introduce mutations at bystander loci, particularly within the 5′ regulatory regions of proto-oncogenes relevant to diffuse large B cell lymphomas (DLBCL). Since current methods for genomewide sequencing such as Exon Capture and RNAseq only target mutations in coding regions, to date non-Ig promoter SHMs have been studied only in a handful genes. We designed a novel approach integrating bioinformatics tools with next generation sequencing technology to identify regulatory loci targeted by SHM genome-wide. We observed increased numbers of SHM associated sequence variant hotspots in lymphoma cells as compared to primary normal germinal center B cells. Many of these SHM hotspots map to genes that have not been reported before as mutated, including BACH2, BTG2, CXCR4, CIITA, EBF1, PIM2, and TCL1A, etc., all of which have potential roles in B cell survival, differentiation, and malignant transformation. In addition, using BCL6 and BACH2 as examples, we demonstrated that SHM sites identified in these 5′ regulatory regions greatly altered their transcription activities in a reporter assay. Our approach provides a first cost-efficient, genome-wide method to identify regulatory mutations and non-Ig SHM hotspots.
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MESH Headings
- B-Lymphocytes/metabolism
- B-Lymphocytes/pathology
- Cell Differentiation/genetics
- Cell Line, Tumor
- Chromatin Immunoprecipitation
- Gene Expression Regulation, Neoplastic
- Genes, Neoplasm/genetics
- Genes, Regulator/genetics
- Genome, Human/genetics
- Histones/metabolism
- Humans
- Lymphoma/genetics
- Lymphoma/immunology
- Lymphoma/pathology
- Lymphoma, Large B-Cell, Diffuse/genetics
- Lymphoma, Large B-Cell, Diffuse/immunology
- Lymphoma, Large B-Cell, Diffuse/pathology
- Methylation
- Polymorphism, Single Nucleotide/genetics
- Promoter Regions, Genetic/genetics
- Sequence Analysis, DNA
- Somatic Hypermutation, Immunoglobulin/genetics
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Affiliation(s)
- Yanwen Jiang
- HRH Prince Alwaleed Bin Talal Bin Abdulaziz Alsaud Institute for Computational Biomedicine and Department of Physiology and Biophysics, Weill Cornell Medical College, New York, New York, United States of America
- Hematology and Oncology Division, Department of Medicine, Weill Cornell Medical College, New York, New York, United States of America
| | - T. David Soong
- HRH Prince Alwaleed Bin Talal Bin Abdulaziz Alsaud Institute for Computational Biomedicine and Department of Physiology and Biophysics, Weill Cornell Medical College, New York, New York, United States of America
| | - Ling Wang
- Hematology and Oncology Division, Department of Medicine, Weill Cornell Medical College, New York, New York, United States of America
| | - Ari M. Melnick
- Hematology and Oncology Division, Department of Medicine, Weill Cornell Medical College, New York, New York, United States of America
- * E-mail: (AM); (OE)
| | - Olivier Elemento
- HRH Prince Alwaleed Bin Talal Bin Abdulaziz Alsaud Institute for Computational Biomedicine and Department of Physiology and Biophysics, Weill Cornell Medical College, New York, New York, United States of America
- * E-mail: (AM); (OE)
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Abstract
Chronic lymphocytic leukemia (CLL) is unique among B cell malignancies in that the malignant clones can be featured either somatically mutated or unmutated IGVH genes. CLL cells that express unmutated immunoglobulin variable domains likely underwent final development prior to their entry into the germinal center, whereas those that express mutated variable domains likely transited through the germinal center and then underwent final development. Regardless, the cellular origin of CLL remains unknown. The aim of this review is to summarize immunological aspects involved in this process and to provide insights about the complex biology and pathogenesis of this disease. We propose a mechanistic hypothesis to explain the origin of B-CLL clones into our current picture of normal B cell development. In particular, we suggest that unmutated CLL arises from normal B cells with self-reactivity for apoptotic bodies that have undergone receptor editing, CD5 expression, and anergic processes in the bone marrow. Similarly, mutated CLL would arise from cells that, while acquiring self-reactivity for autoantigens-including apoptotic bodies-in germinal centers, are also still subject to tolerization mechanisms, including receptor editing and anergy. We believe that CLL is a proliferation of B lymphocytes selected during clonal expansion through multiple encounters with (auto)antigens, despite the fact that they differ in their state of activation and maturation. Autoantigens and microbial pathogens activate BCR signaling and promote tolerogenic mechanisms such as receptor editing/revision, anergy, CD5+ expression, and somatic hypermutation in CLL B cells. The result of these tolerogenic mechanisms is the survival of CLL B cell clones with similar surface markers and homogeneous gene expression signatures. We suggest that both immunophenotypic surface markers and homogenous gene expression might represent the evidence of several attempts to re-educate self-reactive B cells.
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MESH Headings
- Animals
- B-Lymphocytes/immunology
- B-Lymphocytes/metabolism
- B-Lymphocytes/physiology
- Biomarkers, Tumor/analysis
- Biomarkers, Tumor/genetics
- Biomarkers, Tumor/physiology
- Cell Differentiation/genetics
- Cell Differentiation/immunology
- Cell Transformation, Neoplastic/genetics
- Cell Transformation, Neoplastic/immunology
- Gene Expression Profiling
- Humans
- Immune Tolerance/genetics
- Immune Tolerance/physiology
- Leukemia, Lymphocytic, Chronic, B-Cell/diagnosis
- Leukemia, Lymphocytic, Chronic, B-Cell/etiology
- Leukemia, Lymphocytic, Chronic, B-Cell/immunology
- Models, Biological
- Neoplastic Stem Cells/immunology
- Neoplastic Stem Cells/physiology
- Somatic Hypermutation, Immunoglobulin/genetics
- Somatic Hypermutation, Immunoglobulin/physiology
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Affiliation(s)
- Ricardo García-Muñoz
- Hematology Department, Hospital San Pedro, c/Piqueras 98, Logroño, La Rioja, 26006, Spain.
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37
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Gramlich HS, Reisbig T, Schatz DG. AID-targeting and hypermutation of non-immunoglobulin genes does not correlate with proximity to immunoglobulin genes in germinal center B cells. PLoS One 2012; 7:e39601. [PMID: 22768095 PMCID: PMC3387148 DOI: 10.1371/journal.pone.0039601] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [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: 03/13/2012] [Accepted: 05/25/2012] [Indexed: 12/21/2022] Open
Abstract
Upon activation, B cells divide, form a germinal center, and express the activation induced deaminase (AID), an enzyme that triggers somatic hypermutation of the variable regions of immunoglobulin (Ig) loci. Recent evidence indicates that at least 25% of expressed genes in germinal center B cells are mutated or deaminated by AID. One of the most deaminated genes, c-Myc, frequently appears as a translocation partner with the Ig heavy chain gene (Igh) in mouse plasmacytomas and human Burkitt's lymphomas. This indicates that the two genes or their double-strand break ends come into close proximity at a biologically relevant frequency. However, the proximity of c-Myc and Igh has never been measured in germinal center B cells, where many such translocations are thought to occur. We hypothesized that in germinal center B cells, not only is c-Myc near Igh, but other mutating non-Ig genes are deaminated by AID because they are near Ig genes, the primary targets of AID. We tested this "collateral damage" model using 3D-fluorescence in situ hybridization (3D-FISH) to measure the distance from non-Ig genes to Ig genes in germinal center B cells. We also made mice transgenic for human MYC and measured expression and mutation of the transgenes. We found that there is no correlation between proximity to Ig genes and levels of AID targeting or gene mutation, and that c-Myc was not closer to Igh than were other non-Ig genes. In addition, the human MYC transgenes did not accumulate mutations and were not deaminated by AID. We conclude that proximity to Ig loci is unlikely to be a major determinant of AID targeting or mutation of non-Ig genes, and that the MYC transgenes are either missing important regulatory elements that allow mutation or are unable to mutate because their new nuclear position is not conducive to AID deamination.
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Affiliation(s)
- Hillary Selle Gramlich
- Department of Cell Biology, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - Tara Reisbig
- Department of Immunobiology, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - David G. Schatz
- Department of Immunobiology, Yale University School of Medicine, New Haven, Connecticut, United States of America
- Howard Hughes Medical Institute, Chevy Chase, Maryland, United States of America
- * E-mail:
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38
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Péron S, Laffleur B, Denis-Lagache N, Cook-Moreau J, Filloux M, Cogné M. [IgH locus suicide recombination, or when B cells surrender!]. Med Sci (Paris) 2012; 28:551-4. [PMID: 22643012 DOI: 10.1051/medsci/2012285023] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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39
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Geisberger R, Huemer M, Gassner FJ, Zaborsky N, Egle A, Greil R. Lysine residue at position 22 of the AID protein regulates its class switch activity. PLoS One 2012; 7:e30667. [PMID: 22363466 PMCID: PMC3282692 DOI: 10.1371/journal.pone.0030667] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [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: 08/17/2011] [Accepted: 12/27/2011] [Indexed: 02/03/2023] Open
Abstract
BACKGROUND Activation induced deaminase (AID) mediates class switch recombination and somatic hypermutation of immunoglobulin (Ig) genes in germinal centre B cells. In order to regulate its specific activity and as a means to keep off-target mutations low, several mechanisms have evolved, including binding to specific cofactors, phosphorylation and destabilization of nuclear AID protein. Although ubiquitination at lysine residues of AID is recognized as an essential step in initiating degradation of nuclear AID, any functional relevance of lysine modifications has remained elusive. METHODOLOGY/PRINCIPAL FINDINGS Here, we report functional implications of lysine modifications of the human AID protein by generating a panel of lysine to arginine mutants of AID and assessment of their catalytic class switch activity. We found that only mutation of Lys22 to Arg resulted in a significant reduction of class switching to IgG1 in transfected primary mouse B cells. This decrease in activity was neither reflected in reduced hypermutation of Ig genes in AID-mutant transfected DT40 B cell lines nor recapitulated in bacterial deamination assays, pointing to involvement of post-translational modification of Lys22 for AID activity in B cells. CONCLUSIONS/SIGNIFICANCE Our results imply that lysine modification may represent a novel level of AID regulation and that Lys22 is important for effective AID activity.
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Affiliation(s)
- Roland Geisberger
- Laboratory for Immunological and Molecular Cancer Research, IIIrd Medical Department with Hematology, Medical Oncology, Hemostaseology, Rheumatology and Infectiology, Paracelsus Medical University Salzburg, Salzburg, Austria.
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40
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Parsa JY, Ramachandran S, Zaheen A, Nepal RM, Kapelnikov A, Belcheva A, Berru M, Ronai D, Martin A. Negative supercoiling creates single-stranded patches of DNA that are substrates for AID-mediated mutagenesis. PLoS Genet 2012; 8:e1002518. [PMID: 22346767 PMCID: PMC3276561 DOI: 10.1371/journal.pgen.1002518] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [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: 06/07/2011] [Accepted: 12/15/2011] [Indexed: 11/18/2022] Open
Abstract
Antibody diversification necessitates targeted mutation of regions within the immunoglobulin locus by activation-induced cytidine deaminase (AID). While AID is known to act on single-stranded DNA (ssDNA), the source, structure, and distribution of these substrates in vivo remain unclear. Using the technique of in situ bisulfite treatment, we characterized these substrates—which we found to be unique to actively transcribed genes—as short ssDNA regions, that are equally distributed on both DNA strands. We found that the frequencies of these ssDNA patches act as accurate predictors of AID activity at reporter genes in hypermutating and class switching B cells as well as in Escherichia coli. Importantly, these ssDNA patches rely on transcription, and we report that transcription-induced negative supercoiling enhances both ssDNA tract formation and AID mutagenesis. In addition, RNaseH1 expression does not impact the formation of these ssDNA tracts indicating that these structures are distinct from R-loops. These data emphasize the notion that these transcription-generated ssDNA tracts are one of many in vivo substrates for AID. Creating an effective antibody-mediated immune response relies on processes that create antibodies of high affinity and of different functions in order to clear pathogens. Activation-induced cytidine deaminase (AID) is an essential B cell–specific factor that is known to initiate these processes by deaminating dC on single-stranded DNA of actively transcribed genes. AID has also been implicated in deaminating dC at non-antibody genes, resulting in the disregulation of genes that may lead to B cell–related cancers. Until now, it has remained unknown what the source, structure, and distribution of the single-stranded DNA is that AID acts upon. By using a novel assay that allows direct detection of single-stranded DNA within intact cell nuclei, we observed patches of single-stranded DNA that are strongly correlated to the preferred activity of AID. Furthermore, we find that the activity of AID and single-stranded DNA patch formation can be enhanced by negative supercoiling of the DNA, which is a typical consequence of transcription. These findings allow us to better understand how AID is recruited to and mutates antibody genes as well as other genes implicated in cancers of B cell origin.
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Affiliation(s)
- Jahan-Yar Parsa
- Department of Immunology, University of Toronto, Toronto, Canada
| | | | - Ahmad Zaheen
- Department of Immunology, University of Toronto, Toronto, Canada
| | - Rajeev M. Nepal
- Department of Immunology, University of Toronto, Toronto, Canada
| | - Anat Kapelnikov
- Department of Immunology, University of Toronto, Toronto, Canada
| | | | - Maribel Berru
- Department of Immunology, University of Toronto, Toronto, Canada
| | - Diana Ronai
- Howard Hughes Medical Institute, Department of Molecular, Cellular, and Developmental Biology, University of Colorado at Boulder, Boulder, Colorado, United States of America
| | - Alberto Martin
- Department of Immunology, University of Toronto, Toronto, Canada
- * E-mail:
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41
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Abstract
DNA damage, rearrangement, and mutation of the human genome are the basis of carcinogenesis and thought to be avoided at all costs. An exception is the adaptive immune system where lymphocytes utilize programmed DNA damage to effect antigen receptor diversification. Both B and T lymphocytes diversify their antigen receptors through RAG1/2 mediated recombination, but B cells undergo two additional processes--somatic hypermutation (SHM) and class-switch recombination (CSR), both initiated by activation-induced cytidine deaminase (AID). AID deaminates cytidines in DNA resulting in U:G mismatches that are processed into point mutations in SHM or double-strand breaks in CSR. Although AID activity is focused at Immunoglobulin (Ig) gene loci, it also targets a wide array of non-Ig genes including oncogenes associated with lymphomas. Here, we review the molecular basis of AID regulation, targeting, and initiation of CSR and SHM, as well as AID's role in generating chromosome translocations that contribute to lymphomagenesis.
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Affiliation(s)
- Anna Gazumyan
- Laboratory of Molecular Immunology, The Rockefeller University, New York, New York, USA
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42
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Bhagwat AS. Comment on "Deoxyuridine triphosphate incorporation during somatic hypermutation of mouse VkOx genes after immunization with phenyloxazolone". J Immunol 2011; 185:7130-1; author reply 7131. [PMID: 21127314 DOI: 10.4049/jimmunol.1090111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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43
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Abstract
The secondary immunoglobulin gene diversification processes, somatic hypermutation (SHM), immunoglobulin gene conversion (GCV), and class switch recombination, are important for efficient humoral immune responses. They require the action of activation-induced cytidine deaminase, an enzyme that deaminates cytosine in the context of single-stranded DNA. The chicken DT40 B-cell line is an important model system for exploring the mechanisms of SHM and GCV, as both processes occur constitutively without the need for stimulation. In addition, standard gene targeting strategies can be used for defined manipulations of the DT40 genome. Thus, these cells represent an excellent model of choice for genetic studies of SHM and GCV. Problems arising from defects in early B-cell development that are of concern when using genetically engineered mice are avoided in this system. Here, we describe how to perform gene targeting in DT40 cells and how to determine the effects of such modifications on SHM and GCV.
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Affiliation(s)
- Nagarama Kothapalli
- Laboratory of Cellular and Molecular Biology, National Institute on Aging, National Institutes of Health, Baltimore, MD, USA
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44
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Guikema JEJ, Stavnezer J, Schrader CE. The role of Apex2 in class-switch recombination of immunoglobulin genes. Int Immunol 2010; 22:213; author reply 213-4. [PMID: 20185435 DOI: 10.1093/intimm/dxq003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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45
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Robbiani DF, Bunting S, Feldhahn N, Bothmer A, Camps J, Deroubaix S, McBride KM, Klein IA, Stone G, Eisenreich TR, Ried T, Nussenzweig A, Nussenzweig MC. AID produces DNA double-strand breaks in non-Ig genes and mature B cell lymphomas with reciprocal chromosome translocations. Mol Cell 2009; 36:631-41. [PMID: 19941823 DOI: 10.1016/j.molcel.2009.11.007] [Citation(s) in RCA: 197] [Impact Index Per Article: 13.1] [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: 07/06/2009] [Revised: 09/08/2009] [Accepted: 11/09/2009] [Indexed: 11/19/2022]
Abstract
Cancer-initiating translocations such as those associated with lymphomas require the formation of paired DNA double-strand breaks (DSBs). Activation-induced cytidine deaminase (AID) produces widespread somatic mutation in mature B cells; however, the extent of "off-target" DSB formation and its role in translocation-associated malignancy is unknown. Here, we show that deregulated expression of AID causes widespread genome instability, which alone is insufficient to induce B cell lymphoma; transformation requires concomitant loss of the tumor suppressor p53. Mature B cell lymphomas arising as a result of deregulated AID expression are phenotypically diverse and harbor clonal reciprocal translocations involving a group of Immunoglobulin (Ig) and non-Ig genes that are direct targets of AID. This group includes miR-142, a previously unknown micro-RNA target that is translocated in human B cell malignancy. We conclude that AID produces DSBs throughout the genome, which can lead to lymphoma-associated chromosome translocations in mature B cells.
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MESH Headings
- Animals
- B-Lymphocytes/cytology
- B-Lymphocytes/enzymology
- Cell Differentiation/genetics
- Cells, Cultured
- Chromosomal Instability/genetics
- Chromosomes, Mammalian/genetics
- Cytidine Deaminase/metabolism
- DNA Breaks, Double-Stranded
- DNA Damage
- Genes, Immunoglobulin/genetics
- Humans
- Immunoglobulin Class Switching/genetics
- Karyotyping
- Lymphoma, B-Cell/enzymology
- Lymphoma, B-Cell/genetics
- Lymphoma, B-Cell/pathology
- Mice
- Mice, Transgenic
- MicroRNAs/metabolism
- Phenotype
- Proto-Oncogene Proteins c-myc/genetics
- Somatic Hypermutation, Immunoglobulin/genetics
- Translocation, Genetic
- Tumor Suppressor Protein p53/deficiency
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46
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Abstract
B-chronic lymphocytic leukemia (B-CLL) is characterized by a highly variable clinical course which has long remained a stumbling block for clinicians. This variability appears to arise from complex molecular alterations identified in malignant cells from patient subsets. Recent studies have focused in particular on identifying new molecular markers to help predict the most effective and adapted treatments. In addition to the mutation status of immunoglobulin variable heavy-chain region (IgVH) genes, which is a well-established predictive factor in B-CLL, these new markers include defects of cell factors involved in the maintenance of genome stability, such as telomere function, DNA repair, ATM and p53. Other predictive factors, such as tyrosine kinase Zap-70 and soluble factors found in patient sera, may be associated with B-cell receptor signal transduction. Interestingly, an alteration of these factors fits closely, though not strikingly, with the absence of somatic mutations in IgVH genes, suggesting that the latter may be due either to epigenetic events leading to an unstable genome or to an inherited defect in the immune response of malignant B-cells. Recent lessons from Zap-70 expression/phosphorylation suggest that some of these markers may reflect the defective pathways in B-CLL cells rather than being markers of cell malignancy per se. Furthermore, specific subsets of markers are found in patient cells resistant to treatment. Current studies on gene expression profiling and proteomic analyses should soon lead to a better understanding of how these pathways are affected, especially in multi-drug resistant B-CLL.
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Affiliation(s)
- Julien Bouley
- Laboratoire de Radiobiologie et Oncologie, CEA, DSV-DRR, Fontenay aux Roses, France
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47
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Pauklin S, Sernández IV, Bachmann G, Ramiro AR, Petersen-Mahrt SK. Estrogen directly activates AID transcription and function. J Exp Med 2009; 206:99-111. [PMID: 19139166 PMCID: PMC2626679 DOI: 10.1084/jem.20080521] [Citation(s) in RCA: 182] [Impact Index Per Article: 12.1] [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: 03/11/2008] [Accepted: 12/11/2008] [Indexed: 12/21/2022] Open
Abstract
The immunological targets of estrogen at the molecular, humoral, and cellular level have been well documented, as has estrogen's role in establishing a gender bias in autoimmunity and cancer. During a healthy immune response, activation-induced deaminase (AID) deaminates cytosines at immunoglobulin (Ig) loci, initiating somatic hypermutation (SHM) and class switch recombination (CSR). Protein levels of nuclear AID are tightly controlled, as unregulated expression can lead to alterations in the immune response. Furthermore, hyperactivation of AID outside the immune system leads to oncogenesis. Here, we demonstrate that the estrogen-estrogen receptor complex binds to the AID promoter, enhancing AID messenger RNA expression, leading to a direct increase in AID protein production and alterations in SHM and CSR at the Ig locus. Enhanced translocations of the c-myc oncogene showed that the genotoxicity of estrogen via AID production was not limited to the Ig locus. Outside of the immune system (e.g., breast and ovaries), estrogen induced AID expression by >20-fold. The estrogen response was also partially conserved within the DNA deaminase family (APOBEC3B, -3F, and -3G), and could be inhibited by tamoxifen, an estrogen antagonist. We therefore suggest that estrogen-induced autoimmunity and oncogenesis may be derived through AID-dependent DNA instability.
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Affiliation(s)
- Siim Pauklin
- DNA Editing Laboratory, Cancer Research UK, Clare Hall Laboratories, South Mimms, EN6 3LD, England, UK
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48
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Sernández IV, de Yébenes VG, Dorsett Y, Ramiro AR. Haploinsufficiency of activation-induced deaminase for antibody diversification and chromosome translocations both in vitro and in vivo. PLoS One 2008; 3:e3927. [PMID: 19079594 PMCID: PMC2592691 DOI: 10.1371/journal.pone.0003927] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.9] [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: 09/03/2008] [Accepted: 11/13/2008] [Indexed: 12/20/2022] Open
Abstract
The humoral immune response critically relies on the secondary diversification of antibodies. This diversification takes places through somatic remodelling of the antibody genes by two molecular mechanisms, Class Switch Recombination (CSR) and Somatic Hypermutation (SHM). The enzyme Activation Induced Cytidine Deaminase (AID) initiates both SHM and CSR by deaminating cytosine residues on the DNA of immunoglobulin genes. While crucial for immunity, AID-catalysed deamination is also the triggering event for the generation of lymphomagenic chromosome translocations. To address whether restricting the levels of AID expression in vivo contributes to the regulation of its function, we analysed mice harbouring a single copy of the AID gene (AID+/−). AID+/− mice express roughly 50% of normal AID levels, and display a mild hyperplasia, reminiscent of AID deficient mice and humans. Moreover, we found that AID+/− cells have an impaired competence for CSR and SHM, which indicates that AID gene dose is limiting for its physiologic function. We next evaluated the impact of AID reduction in AID+/− mice on the generation of chromosome translocations. Our results show that the frequency of AID-promoted c-myc/IgH translocations is reduced in AID+/− mice, both in vivo and in vitro. Therefore, AID is haploinsufficient for antibody diversification and chromosome translocations. These findings suggest that limiting the physiologic levels of AID expression can be a regulatory mechanism that ensures an optimal balance between immune proficiency and genome integrity.
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Affiliation(s)
- Isora V. Sernández
- DNA Hypermutation and Cancer Group, Spanish National Cancer Research Center (CNIO), Madrid, Spain
| | - Virginia G. de Yébenes
- DNA Hypermutation and Cancer Group, Spanish National Cancer Research Center (CNIO), Madrid, Spain
| | - Yair Dorsett
- The Rockefeller University, New York, New York, United States of America
| | - Almudena R. Ramiro
- DNA Hypermutation and Cancer Group, Spanish National Cancer Research Center (CNIO), Madrid, Spain
- * E-mail:
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49
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Wright BE, Schmidt KH, Minnick MF, Davis N. I. VH gene transcription creates stabilized secondary structures for coordinated mutagenesis during somatic hypermutation. Mol Immunol 2008; 45:3589-99. [PMID: 18585784 DOI: 10.1016/j.molimm.2008.02.030] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [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: 01/14/2008] [Accepted: 02/29/2008] [Indexed: 02/01/2023]
Abstract
During the adaptive immune response, antigen challenge triggers a million-fold increase in mutation rates in the variable-region antibody genes. The frequency of mutation is causally and directly linked to transcription, which provides ssDNA and drives supercoiling that stabilizes secondary structures containing unpaired, intrinsically mutable bases. Simulation analysis of transcription in VH5 reveals a dominant 65nt secondary structure in the non-transcribed strand containing six sites of mutable ssDNA that have also been identified independently in human B cell lines and in primary mouse B cells. This dominant structure inter-converts briefly with less stable structures and is formed repeatedly during transcription, due to periodic pauses and backtracking. In effect, this creates a stable yet dynamic "mutability platform" consisting of ever-changing patterns of unpaired bases that are simultaneously exposed and therefore able to coordinate mutagenesis. Such a complex of secondary structures may be the source of ssDNA for enzyme-based diversification, which ultimately results in high affinity antibodies.
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Affiliation(s)
- Barbara E Wright
- Division of Biological Sciences, The University of Montana, Missoula, MT 59812, USA.
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50
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Mao ZR, Rosenwald A, Zhang SJ, Zhou R, Mueller-Hermelink HK. [Clonality analysis and mutation status of IgVH genes in classic Richter's syndrome]. Zhonghua Bing Li Xue Za Zhi 2008; 37:364-370. [PMID: 19031714] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
OBJECTIVE To study the clonal rearrangements and mutation status of IgVH genes in classic Richter's syndrome, the relationship between molecular findings of IgVH gene and clinical outcome, and to deciper the possible molecular mechanism of transformation. METHODS The clonal rearrangements and mutation status of IgVH genes were analyzed in cases of classic Richter's syndrome by Genescan and sequencing. Immunohistochemical study for zeta-chain associated protein kinase 70 kDa (ZAP70), p53 and interferon regulation factor 4 (IRF-4) was also performed. RESULTS Samples of 18 cases of B-chronic lymphocytic leukemia (B-CLL)/ diffuse large B-cell lymphoma (DLBCL,78. 3%) had identical tumor cell clones, whereas DLBCL developed as a clonally independent neoplasm in 5 patients (21.7%). Among the clonally related group, 12 cases carried unmutated VH genes in both B-CLL and DLBCL components and VH3-23, VH3-74 and VH1-2 were accounted for the B-CLL transformation to DLBCL. Immunohistochemical study showed that the transformed DLBCL expressed CD5 in 32.1% of cases, CD23 in 14.3%, ZAP70 in 23.8%, p53 in 80.6% and IRF-4 in 82.6% of the cases respectively. Follow-up data were available in 17 patients with classic Richter's syndrome. The median survival period was 7 months. No significant difference in survival rate was obtained between the clonally related or unrelated groups, between IgVH gene mutated or unmutated groups, and between the groups with or without expression of ZAP70, p53 and IRF-4. CONCLUSIONS The ratio of clonally related transformed DLBCL from B-CLL to clonally unrelated DLBCL is 2:1. Clonal transformation to DLBCL predominantly occurs in B-CLL patients carrying unmutated IgVH genes. The biased IgVH gene usage suggests antigens are involved in classic Richter's syndrome. Molecular differences of IgVH genes and very poor clinical outcome of this group of transformed DLBCL indicate that there cases may be regarded as a distinct subset of DLBCL.
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Affiliation(s)
- Zheng-rong Mao
- Department of Pathology and Pathophysiology, School of Medicine, Zhejiang University, Hangzhou 310058, China.
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