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Mompó SM, González-Fernández Á. Antigen-Specific Human Monoclonal Antibodies from Transgenic Mice. Methods Mol Biol 2018; 1904:253-291. [PMID: 30539474 DOI: 10.1007/978-1-4939-8958-4_11] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Due to the difficulties found when generating fully human monoclonal antibodies (mAbs) by the traditional method, several efforts have attempted to overcome these problems, with varying levels of success. One approach has been the development of transgenic mice carrying immunoglobulin (Ig) genes in germline configuration. The engineered mouse genome can undergo productive rearrangement in the B-cell population, with the generation of mouse B lymphocytes expressing human Ig (hIg) chains. To avoid the expression of mouse heavy or light chains, the endogenous mouse Ig (mIg) loci must be silenced by gene-targeting techniques. Subsequently, to obtain antigen-specific mAbs, conventional immunization protocols can be followed and the mAb technique used (fusion of activated B cells with mouse myeloma cells, screening, cloning, freezing, and testing) with these animThis chapter summarizes the most common chromatographic mAb andals expressing human Ig genes. This chapter describes the type of transgenic-knockout mice generated for various research groups, provides examples of human mAbs developed by research groups and companies, and includes protocols of immunization, generation, production, and purification of human mAbs from such mice. In addition, it also addresses the problems detected, and includes some of the methods that can be used to analyze functional activities with human mAbs.
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Affiliation(s)
- Susana Magadán Mompó
- Immunology, Centro de Investigaciones Biomédicas (CINBIO), Centro de Investigación Singular de Galicia, Instituto de Investigación Sanitaria Galicia Sur, Universidad de Vigo, Vigo, Spain
| | - África González-Fernández
- Immunology, Centro de Investigaciones Biomédicas (CINBIO), Centro de Investigación Singular de Galicia, Instituto de Investigación Sanitaria Galicia Sur, Universidad de Vigo, Vigo, Spain.
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Brüggemann M, Osborn MJ, Ma B, Hayre J, Avis S, Lundstrom B, Buelow R. Human antibody production in transgenic animals. Arch Immunol Ther Exp (Warsz) 2014; 63:101-8. [PMID: 25467949 PMCID: PMC4359279 DOI: 10.1007/s00005-014-0322-x] [Citation(s) in RCA: 85] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2014] [Accepted: 11/19/2014] [Indexed: 11/26/2022]
Abstract
Fully human antibodies from transgenic animals account for an increasing number of new therapeutics. After immunization, diverse human monoclonal antibodies of high affinity can be obtained from transgenic rodents, while large animals, such as transchromosomic cattle, have produced respectable amounts of specific human immunoglobulin (Ig) in serum. Several strategies to derive animals expressing human antibody repertoires have been successful. In rodents, gene loci on bacterial artificial chromosomes or yeast artificial chromosomes were integrated by oocyte microinjection or transfection of embryonic stem (ES) cells, while ruminants were derived from manipulated fibroblasts with integrated human chromosome fragments or human artificial chromosomes. In all strains, the endogenous Ig loci have been silenced by gene targeting, either in ES or fibroblast cells, or by zinc finger technology via DNA microinjection; this was essential for optimal production. However, comparisons showed that fully human antibodies were not as efficiently produced as wild-type Ig. This suboptimal performance, with respect to immune response and antibody yield, was attributed to imperfect interaction of the human constant region with endogenous signaling components such as the Igα/β in mouse, rat or cattle. Significant improvements were obtained when the human V-region genes were linked to the endogenous CH-region, either on large constructs or, separately, by site-specific integration, which could also silence the endogenous Ig locus by gene replacement or inversion. In animals with knocked-out endogenous Ig loci and integrated large IgH loci, containing many human Vs, all D and all J segments linked to endogenous C genes, highly diverse human antibody production similar to normal animals was obtained.
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Affiliation(s)
- Marianne Brüggemann
- Recombinant Antibody Technology Ltd., Babraham Research Campus, Babraham, Cambridge CB22 3AT UK
- Open Monoclonal Technology, Inc., Palo Alto, CA 94303 USA
| | - Michael J. Osborn
- Recombinant Antibody Technology Ltd., Babraham Research Campus, Babraham, Cambridge CB22 3AT UK
| | - Biao Ma
- Recombinant Antibody Technology Ltd., Babraham Research Campus, Babraham, Cambridge CB22 3AT UK
| | - Jasvinder Hayre
- Recombinant Antibody Technology Ltd., Babraham Research Campus, Babraham, Cambridge CB22 3AT UK
| | - Suzanne Avis
- Recombinant Antibody Technology Ltd., Babraham Research Campus, Babraham, Cambridge CB22 3AT UK
| | | | - Roland Buelow
- Open Monoclonal Technology, Inc., Palo Alto, CA 94303 USA
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Mompó SM, González-Fernández A. Antigen-specific human monoclonal antibodies from transgenic mice. Methods Mol Biol 2014; 1060:245-276. [PMID: 24037845 DOI: 10.1007/978-1-62703-586-6_13] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Due to the difficulties found when generating fully human monoclonal antibodies (mAbs) by the traditional method, several efforts have attempted to overcome these problems, with varying levels of success. One approach has been the development of transgenic mice carrying immunoglobulin (Ig) genes in germ line configuration. The engineered mouse genome can undergo productive rearrangement in the B cell population, with the generation of mouse B lymphocytes expressing human Ig (hIg) chains. To avoid the expression of mouse heavy or light chains, the endogenous mouse Ig (mIg) loci must be silenced by gene-targeting techniques. Subsequently, to obtain antigen-specific mAbs, conventional immunization protocols can be followed and the mAb technique used (fusion of activated B cells with mouse myeloma cells, screening, cloning, freezing, and testing) with these animals expressing human Ig genes. This chapter describes the type of transgenic knockout mice generated for various research groups, provides examples of human mAbs developed by research groups and companies, and includes protocols of immunization, generation, production, and purification of human mAbs from such mice. In addition, it also addresses the problems detected, and includes some of the methods that can be used to analyze functional activities with human mAbs.
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4
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Ma B, Osborn MJ, Avis S, Ouisse LH, Ménoret S, Anegon I, Buelow R, Brüggemann M. Human antibody expression in transgenic rats: comparison of chimeric IgH loci with human VH, D and JH but bearing different rat C-gene regions. J Immunol Methods 2013; 400-401:78-86. [PMID: 24184135 DOI: 10.1016/j.jim.2013.10.007] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2013] [Revised: 10/18/2013] [Accepted: 10/18/2013] [Indexed: 11/28/2022]
Abstract
Expression of human antibody repertoires in transgenic animals has been accomplished by introducing large human Ig loci into mice and, more recently, a chimeric IgH locus into rats. With human VH, D and JH genes linked to the rat C-region antibody expression was significantly increased, similar to wild-type levels not found with fully human constructs. Here we compare four rat-lines containing the same human VH-region (comprising 22 VHs, all Ds and all JHs in natural configuration) but linked to different rat CH-genes and regulatory sequences. The endogenous IgH locus was silenced by zinc-finger nucleases. After breeding, all lines produced exclusively chimeric human H-chain with near normal IgM levels. However, in two lines poor IgG expression and inefficient immune responses were observed, implying that high expression, class-switching and hypermutation are linked to optimal enhancer function provided by the large regulatory region at the 3' end of the IgH locus. Furthermore, exclusion of Cδ and its downstream interval region may assist recombination. Highly diverse IgG and immune responses similar to normal rats were identified in two strains carrying diverse and differently spaced C-genes.
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Affiliation(s)
- Biao Ma
- Recombinant Antibody Technology Ltd., Cambridge, UK
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5
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Osborn MJ, Ma B, Avis S, Binnie A, Dilley J, Yang X, Lindquist K, Ménoret S, Iscache AL, Ouisse LH, Rajpal A, Anegon I, Neuberger MS, Buelow R, Brüggemann M. High-affinity IgG antibodies develop naturally in Ig-knockout rats carrying germline human IgH/Igκ/Igλ loci bearing the rat CH region. THE JOURNAL OF IMMUNOLOGY 2013; 190:1481-90. [PMID: 23303672 DOI: 10.4049/jimmunol.1203041] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Mice transgenic for human Ig loci are an invaluable resource for the production of human Abs. However, such mice often do not yield human mAbs as effectively as conventional mice yield mouse mAbs. Suboptimal efficacy in delivery of human Abs might reflect imperfect interaction between the human membrane IgH chains and the mouse cellular signaling machinery. To obviate this problem, in this study we generated a humanized rat strain (OmniRat) carrying a chimeric human/rat IgH locus (comprising 22 human V(H)s, all human D and J(H) segments in natural configuration linked to the rat C(H) locus) together with fully human IgL loci (12 Vκs linked to Jκ-Cκ and 16 Vλs linked to Jλ-Cλ). The endogenous Ig loci were silenced using designer zinc finger nucleases. Breeding to homozygosity resulted in a novel transgenic rat line exclusively producing chimeric Abs with human idiotypes. B cell recovery was indistinguishable from wild-type animals, and human V(D)J transcripts were highly diverse. Following immunization, the OmniRat strain performed as efficiently as did normal rats in yielding high-affinity serum IgG. mAbs, comprising fully human variable regions with subnanomolar Ag affinity and carrying extensive somatic mutations, are readily obtainable, similarly to conventional mAbs from normal rats.
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Affiliation(s)
- Michael J Osborn
- Recombinant Antibody Technology Ltd., Babraham Research Campus, Babraham, Cambridge CB22 3AT, United Kingdom
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Pruzina S, Williams GT, Kaneva G, Davies SL, Martin-Lopez A, Bruggemann M, Vieira SM, Jeffs SA, Sattentau QJ, Neuberger MS. Human monoclonal antibodies to HIV-1 gp140 from mice bearing YAC-based human immunoglobulin transloci. Protein Eng Des Sel 2011; 24:791-9. [DOI: 10.1093/protein/gzr038] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Pinaud E, Marquet M, Fiancette R, Péron S, Vincent-Fabert C, Denizot Y, Cogné M. The IgH locus 3' regulatory region: pulling the strings from behind. Adv Immunol 2011; 110:27-70. [PMID: 21762815 DOI: 10.1016/b978-0-12-387663-8.00002-8] [Citation(s) in RCA: 92] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Antigen receptor gene loci are among the most complex in mammals. The IgH locus, encoding the immunoglobulin heavy chain (IgH) in B-lineage cells, undergoes major transcription-dependent DNA remodeling events, namely V(D)J recombination, Ig class-switch recombination (CSR), and somatic hypermutation (SHM). Various cis-regulatory elements (encompassing promoters, enhancers, and chromatin insulators) recruit multiple nuclear factors in order to ensure IgH locus regulation by tightly orchestrated physical and/or functional interactions. Among major IgH cis-acting regions, the large 3' regulatory region (3'RR) located at the 3' boundary of the locus includes several enhancers and harbors an intriguing quasi-palindromic structure. In this review, we report progress insights made over the past decade in order to describe in more details the structure and functions of IgH 3'RRs in mouse and human. Generation of multiple cellular, transgenic and knock-out models helped out to decipher the function of the IgH 3' regulatory elements in the context of normal and pathologic B cells. Beside its interest in physiology, the challenge of elucidating the locus-wide cross talk between distant cis-regulatory elements might provide useful insights into the mechanisms that mediate oncogene deregulation after chromosomal translocations onto the IgH locus.
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Affiliation(s)
- Eric Pinaud
- UMR CNRS 6101, Centre National de la Recherche Scientifique, Université de Limoges, Limoges, France
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Van Keuren ML, Gavrilina GB, Filipiak WE, Zeidler MG, Saunders TL. Generating transgenic mice from bacterial artificial chromosomes: transgenesis efficiency, integration and expression outcomes. Transgenic Res 2009; 18:769-85. [PMID: 19396621 DOI: 10.1007/s11248-009-9271-2] [Citation(s) in RCA: 103] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2009] [Accepted: 04/14/2009] [Indexed: 11/27/2022]
Abstract
Transgenic mice are widely used in biomedical research to study gene expression, developmental biology, and gene therapy models. Bacterial artificial chromosome (BAC) transgenes direct gene expression at physiological levels with the same developmental timing and expression patterns as endogenous genes in transgenic animal models. We generated 707 transgenic founders from 86 BAC transgenes purified by three different methods. Transgenesis efficiency was the same for all BAC DNA purification methods. Polyamine microinjection buffer was essential for successful integration of intact BAC transgenes. There was no correlation between BAC size and transgenic rate, birth rate, or transgenic efficiency. A narrow DNA concentration range generated the best transgenic efficiency. High DNA concentrations reduced birth rates while very low concentrations resulted in higher birth rates and lower transgenic efficiency. Founders with complete BAC integrations were observed in all 47 BACs for which multiple markers were tested. Additional founders with BAC fragment integrations were observed for 65% of these BACs. Expression data was available for 79 BAC transgenes and expression was observed in transgenic founders from 63 BACs (80%). Consistent and reproducible success in BAC transgenesis required the combination of careful DNA purification, the use of polyamine buffer, and sensitive genotyping assays.
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Affiliation(s)
- Margaret L Van Keuren
- Transgenic Animal Model Core, University of Michigan Medical School, 2560 MSRB II, Ann Arbor, MI 48109, USA
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Janssens R, Dekker S, Hendriks RW, Panayotou G, van Remoortere A, San JKA, Grosveld F, Drabek D. Generation of heavy-chain-only antibodies in mice. Proc Natl Acad Sci U S A 2006; 103:15130-5. [PMID: 17015837 PMCID: PMC1586177 DOI: 10.1073/pnas.0601108103] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
We have generated transgenic mice containing hybrid llama/human antibody loci that contain two llama variable regions and the human D, J, and Cmu and/or Cgamma constant regions. Such loci rearrange productively and rescue B cell development efficiently without LC rearrangement. Heavy-chain-only antibodies (HCAb) are expressed at high levels, provided that the CH1 domain is deleted from the constant regions. HCAb production does not require an IgM stage for effective pre-B cell signaling. Antigen-specific heavy-chain-only IgM or IgGs are produced upon immunization. The IgG is dimeric, whereas IgM is multimeric. The chimeric HCAb loci are subject to allelic exclusion, but several copies of the transgenic locus can be rearranged and expressed successfully on the same allele in the same cell. Such cells are not subject to negative selection. The mice produce a full antibody repertoire and provide a previously undescribed avenue to produce specific human HCAb in the future.
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Affiliation(s)
| | | | - Rudi W. Hendriks
- Immunology, ErasmusMC, P.O. Box 2040, 3000 CA, Rotterdam, The Netherlands
| | - George Panayotou
- Biomedical Sciences Research Center, Alexander Fleming, Varkiza 16602, Greece; and
| | - Alexandra van Remoortere
- Department of Parasitology, Leiden University Medical Center, Albinusdreef 2, 2333 ZA, Leiden, The Netherlands
| | | | - Frank Grosveld
- *Departments of Cell Biology and
- To whom correspondence should be addressed. E-mail:
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10
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Transgenic non-human animals capable of producing heterologous antibodies. Expert Opin Ther Pat 2005. [DOI: 10.1517/13543776.8.9.1185] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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11
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Novoa-Takara L, Perkins SL, Qi D, Shidham VB, Vesole DH, Hariharan S, Luo Y, Ewton A, Chang CC. Histogenetic phenotypes of B cells in posttransplant lymphoproliferative disorders by immunohistochemical analysis correlate with transplant type: solid organ vs hematopoietic stem cell transplantation. Am J Clin Pathol 2005; 123:104-12. [PMID: 15762285 DOI: 10.1309/dw2tw2087bxl2brk] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
Abstract
We immunohistochemically defined the histogenesis of posttransplantation lymphoproliferative disorders (PTLDs; B-cell phenotype) occurring after allogeneic T cell-depleted hematopoietic stem cell transplantation (HSCT; n = 15) or solid organ transplantation (SOT; n = 11) to determine whether transplantation type or morphologic subtype of PTLD affected the histogenetic subtype. Immunohistochemical stains using histogenetic markers for germinal center (GC) B cells, late GC and post-GC B cells, and post-GC B cells were performed on paraffin-embedded samples. Morphologically, 14 cases were polymorphic; 12 were monomorphic. Histogenetic marker expression was as follows: 1 monomorphic case (4%), GC phenotype expressing bcl-6 and CD10; 17 cases (65%; polymorphic, 9; monomorphic, 8), late GC-early post-GC phenotype expressing MUM1/IRF4; 8 cases (31%; polymorphic, 5; monomorphic, 3), post-GC phenotype expressing MUM1/IRF4 and CD138 but not bcl-6. PTLD cases after HSCT more frequently were post-GC phenotype than after SOT (7/15 vs 1/11, respectively; P = .040) and were independent of morphologic subclassification. Results suggest that most PTLDs are late GC-early post-GC phenotype with a minor group of post-GC phenotype and rare cases of GC phenotype. Findings also suggest a correlation between histogenetic phenotype of B-cell PTLD and type of transplantation.
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Pinaud E, Khamlichi AA, Le Morvan C, Drouet M, Nalesso V, Le Bert M, Cogné M. Localization of the 3' IgH locus elements that effect long-distance regulation of class switch recombination. Immunity 2001; 15:187-99. [PMID: 11520455 DOI: 10.1016/s1074-7613(01)00181-9] [Citation(s) in RCA: 175] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Four transcriptional enhancers lie downstream of the immunoglobulin heavy chain locus: Calpha3'/hs3a, hs1,2, hs3b, and hs4. Although individually weak, these elements have strong transcriptional synergies when combined and they altogether behave as a locus control region. Previous knockout experiments in the 3' region have shown that both hs3a and hs1,2 are dispensable for normal expression and rearrangement of the IgH locus but that their replacement with a transcribed neo gene severely affects class switch recombination. Here we show that even in the absence of a neo gene, joint deletion of the last two 3' enhancers, hs3b and hs4, severely impairs germline transcription and class switching to most isotypes and may in addition affect mu gene expression in resting B cells.
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Affiliation(s)
- E Pinaud
- Laboratoire d'Immunologie, CNRS UMR6101, Faculté de Médecine, Limoges, France
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Khamlichi AA, Pinaud E, Decourt C, Chauveau C, Cogné M. The 3' IgH regulatory region: a complex structure in a search for a function. Adv Immunol 2001; 75:317-45. [PMID: 10879288 DOI: 10.1016/s0065-2776(00)75008-5] [Citation(s) in RCA: 85] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- A A Khamlichi
- CNRS EP 118, Laboratoire d'Immunologie, Limoges, France
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Nicholson IC, Zou X, Popov AV, Cook GP, Corps EM, Humphries S, Ayling C, Goyenechea B, Xian J, Taussig MJ, Neuberger MS, Brüggemann M. Antibody Repertoires of Four- and Five-Feature Translocus Mice Carrying Human Immunoglobulin Heavy Chain and κ and λ Light Chain Yeast Artificial Chromosomes. THE JOURNAL OF IMMUNOLOGY 1999. [DOI: 10.4049/jimmunol.163.12.6898] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Abstract
We have produced mice that carry the human Ig heavy (IgH) and both κ and λ light chain transloci in a background in which the endogenous IgH and κ loci have been inactivated. The B lymphocyte population in these translocus mice is restored to about one-third of normal levels, with preferential (3:1) expression of human λ over human κ. Human IgM is found in the serum at levels between 50 and 400 μg/ml and is elevated following immunization. This primary human Ab repertoire is sufficient to yield diverse Ag-specific responses as judged by analysis of mAbs. The use of DH and J segments is similar to that seen in human B cells, with an analogous pattern of N nucleotide insertion. Maturation of the response is accompanied by somatic hypermutation, which is particularly effective in the light chain transloci. These mice therefore allow the production of Ag-specific repertoires of both IgM,κ and IgM,λ Abs and should prove useful for the production of human mAbs for clinical use.
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Affiliation(s)
| | | | | | - Graham P. Cook
- ‡Laboratory of Molecular Biology, Medical Research Council, Cambridge, United Kingdom
| | - Elaine M. Corps
- †Laboratory of Molecular Recognition, The Babraham Institute, Babraham, Cambridge, United Kingdom; and
| | - Sally Humphries
- †Laboratory of Molecular Recognition, The Babraham Institute, Babraham, Cambridge, United Kingdom; and
| | | | | | - Jian Xian
- *Laboratory of Developmental Immunology and
| | - Michael J. Taussig
- †Laboratory of Molecular Recognition, The Babraham Institute, Babraham, Cambridge, United Kingdom; and
| | - Michael S. Neuberger
- ‡Laboratory of Molecular Biology, Medical Research Council, Cambridge, United Kingdom
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Lubon H. Transgenic animal bioreactors in biotechnology and production of blood proteins. BIOTECHNOLOGY ANNUAL REVIEW 1999; 4:1-54. [PMID: 9890137 DOI: 10.1016/s1387-2656(08)70066-8] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The regulatory elements of genes used to target the tissue-specific expression of heterologous human proteins have been studied in vitro and in transgenic mice. Hybrid genes exhibiting the desired performance have been introduced into large animals. Complex proteins like protein C, factor IX, factor VIII, fibrinogen and hemoglobin, in addition to simpler proteins like alpha 1-antitrypsin, antithrombin III, albumin and tissue plasminogen activator have been produced in transgenic livestock. The amount of functional protein secreted when the transgene is expressed at high levels may be limited by the required posttranslational modifications in host tissues. This can be overcome by engineering the transgenic bioreactor to express the appropriate modifying enzymes. Genetically engineered livestock are thus rapidly becoming a choice for the production of recombinant human blood proteins.
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Affiliation(s)
- H Lubon
- Plasma Derivatives Department, American Red Cross, Rockville, Maryland, USA.
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Neuberger MS, Ehrenstein MR, Klix N, Jolly CJ, Yélamos J, Rada C, Milstein C. Monitoring and interpreting the intrinsic features of somatic hypermutation. Immunol Rev 1998; 162:107-16. [PMID: 9602357 DOI: 10.1111/j.1600-065x.1998.tb01434.x] [Citation(s) in RCA: 100] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
We have used both normal and transgenic mice to analyse the recruitment and targeting of somatic hypermutation to the immunoglobulin loci. We compare methods for analysing hypermutation and discuss how large databases of mutations can be assembled by PCR amplification of the rearranged V-gene flanks from the germinal centre B cells of normal mice as well as by transgene-specific amplification from transgenic B cells. Such studies confirm that hypermutation is preferentially targeted to the immunoglobulin V gene with the bcl6 gene, for example, escaping this intense mutational targeting in germinal centre B cells. We review our data concerning the nature of the hypermutation domain and the targeting of hotspots within that domain. We consider how enhancer-mediated recruitment of hypermutation to the immunoglobulin loci operates in a clonally maintained fashion and illustrate how both the degree of expression and demethylation of the transgene broadly correlate with its mutability.
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Affiliation(s)
- M S Neuberger
- Medical Research Council Laboratory of Molecular Biology, Cambridge, UK.
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Abstract
Transgenic mice have been created that carry human immunoglobulin heavy and light chain genes in germline configuration and that have the corresponding endogenous genes silenced. The transgenes are either minigene constructs or large, almost authentic, transloci on yeast artificial chromosomes and undergo B-cell-specific DNA rearrangement and hypermutation in the mouse lymphoid tissue. Monoclonal antibodies with good affinities for human antigens have been obtained after immunisation. These mice may be a future source of human antibodies for therapy.
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Affiliation(s)
- M Brüggemann
- Laboratory of Developmental Immunology and Translocus Therapeutics, Ltd., Babraham Institute, Cambridge, UK.
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