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Charrin S, Palmulli R, Billard M, Clay D, Boucheix C, Van Niel G, Rubinstein E. Rapid Isolation of Rare Isotype-Switched Hybridoma Variants: Application to the Generation of IgG2a and IgG2b MAb to CD63, a Late Endosome and Exosome Marker. Antibodies (Basel) 2020; 9:antib9030029. [PMID: 32630723 PMCID: PMC7551895 DOI: 10.3390/antib9030029] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Revised: 05/27/2020] [Accepted: 06/11/2020] [Indexed: 12/17/2022] Open
Abstract
CD63, a member of the tetraspanin superfamily, is used as a marker of late endosomes and lysosome-related organelles, as well as a marker of exosomes. Here, we selected rare isotype variants of TS63 by sorting hybridoma cells on the basis of their high expression of surface immunoglobulins of the IgG2a and IgG2b subclass. Pure populations of cells secreting IgG2a and IgG2b variants of TS63 (referred to as TS63a and TS63b) were obtained using two rounds of cell sorting and one limited dilution cloning step. We validate that these new TS63 variants are suitable for co-labeling with mAb of the IgG1 subclass directed to other molecules, using anti mouse subclass antibodies, and for the labeling of exosomes through direct binding to protein A-coated gold particles. These mAbs will be useful to study the intracellular localization of various proteins and facilitate electron microscopy analysis of CD63 localization.
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Affiliation(s)
- Stéphanie Charrin
- Centre d’Immunologie et des Maladies Infectieuses, Inserm, CNRS, Sorbonne Université, CIMI-Paris, 75013 Paris, France;
| | - Roberta Palmulli
- Centre National de la Recherche Scientifique, Structure and Membrane Compartments, Institut Curie, Paris Sciences & Lettres Research University, UMR144, 75005 Paris, France;
| | - Martine Billard
- Modèles de cellules souches malignes et thérapeutiques, Inserm, Université Paris-Saclay, 94800 Villejuif, France; (M.B.); (C.B.)
| | - Denis Clay
- Inserm, Université Paris-Saclay, UMS44, F-94800 Villejuif, France;
| | - Claude Boucheix
- Modèles de cellules souches malignes et thérapeutiques, Inserm, Université Paris-Saclay, 94800 Villejuif, France; (M.B.); (C.B.)
| | - Guillaume Van Niel
- Institute of Psychiatry and Neuroscience of Paris (IPNP), Inserm, Université de Paris, U1266, F-75014 Paris, France;
| | - Eric Rubinstein
- Centre d’Immunologie et des Maladies Infectieuses, Inserm, CNRS, Sorbonne Université, CIMI-Paris, 75013 Paris, France;
- Correspondence: ; Tel.: +33-1-4077-9898
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Argentieri MC, Pilla D, Vanzati A, Lonardi S, Facchetti F, Doglioni C, Parravicini C, Cattoretti G. Antibodies are forever: a study using 12-26-year-old expired antibodies. Histopathology 2013; 63:869-76. [DOI: 10.1111/his.12225] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2013] [Accepted: 07/06/2013] [Indexed: 01/23/2023]
Affiliation(s)
| | - Daniela Pilla
- Department of Pathology; AO San Gerardo; Monza Italy
| | - Alice Vanzati
- Department of Pathology; AO San Gerardo; Monza Italy
- Department of Surgical Sciences; Universitá degli Studi di Milano Bicocca; Milan Italy
| | - Silvia Lonardi
- Department of Pathology; University of Brescia, Spedali Civili; Brescia Italy
| | - Fabio Facchetti
- Department of Pathology; University of Brescia, Spedali Civili; Brescia Italy
| | | | | | - Giorgio Cattoretti
- Department of Pathology; AO San Gerardo; Monza Italy
- Department of Surgical Sciences; Universitá degli Studi di Milano Bicocca; Milan Italy
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Abboud N, Chow SK, Saylor C, Janda A, Ravetch JV, Scharff MD, Casadevall A. A requirement for FcγR in antibody-mediated bacterial toxin neutralization. ACTA ACUST UNITED AC 2010; 207:2395-405. [PMID: 20921285 PMCID: PMC2964574 DOI: 10.1084/jem.20100995] [Citation(s) in RCA: 90] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Constant regions of antibodies influence toxin neutralization in a manner dependent on FcγR. One important function of humoral immunity is toxin neutralization. The current view posits that neutralization results from antibody-mediated interference with the binding of toxins to their targets, a phenomenon viewed as dependent only on antibody specificity. To investigate the role of antibody constant region function in toxin neutralization, we generated IgG2a and IgG2b variants of the Bacillus anthracis protective antigen–binding IgG1 monoclonal antibody (mAb) 19D9. These antibodies express identical variable regions and display the same specificity. The efficacy of antibody-mediated neutralization was IgG2a > IgG2b > IgG1, and neutralization activity required competent Fcγ receptor (FcγR). The IgG2a mAb prevented lethal toxin cell killing and mitogen-activated protein kinase/extracellular signal-regulated kinase kinase cleavage more efficiently than the IgG1 mAb. Passive immunization with IgG1 and IgG2a mAb protected wild-type mice, but not FcγR-deficient mice, against B. anthracis infection. These results establish that constant region isotype influences toxin neutralization efficacy of certain antibodies through a mechanism that requires engagement of FcγR. These findings highlight a new parameter for evaluating vaccine responses and the possibility of harnessing optimal FcγR interactions in the design of passive immunization strategies.
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Affiliation(s)
- Nareen Abboud
- Department of Microbiology and Immunology, Division of Infectious Diseases, Albert Einstein College of Medicine, Bronx, NY 10461, USA
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Iglesias-Ussel MD, Zavadil J, Scharff MD. Molecular characterization of hybridoma subclones spontaneously switching at high frequencies in vitro. J Immunol Methods 2009; 350:71-8. [PMID: 19619554 DOI: 10.1016/j.jim.2009.07.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2009] [Revised: 06/24/2009] [Accepted: 07/02/2009] [Indexed: 12/22/2022]
Abstract
The hybridoma technology allows the production of large quantities of specific antibodies of a single isotype. Since different isotypes have special effector functions and are distributed distinctively throughout the body, it is often useful to have a library of switch variants from the original monoclonal antibody. We have shown previously that forced expression of activation induced cytidine deaminase (AID) in hybridomas increased their very low frequency of class switch recombination (CSR) in vitro only approximately 7-13 fold. Since we had previously identified rare hybridoma subclones that spontaneously switched at more than 100 times higher frequencies, we have now examined those higher switching variants to search for ways to further increase the frequency of isotype switching in vitro. AID was not responsible for the approximately 100 fold increase in CSR, so we used whole-genome gene expression profiling to provide a platform for studying candidate molecular pathways underlying spontaneous CSR in hybridomas.
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Iglesias-Ussel MD, Fan M, Li Z, Martin A, Scharff MD. Forced expression of AID facilitates the isolation of class switch variants from hybridoma cells. J Immunol Methods 2006; 316:59-66. [PMID: 16997317 PMCID: PMC2677521 DOI: 10.1016/j.jim.2006.08.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2006] [Accepted: 08/10/2006] [Indexed: 11/24/2022]
Abstract
Monoclonal antibodies are used in the treatment and diagnosis of diseases and to study the protective and adverse functions of antibodies in vitro and in vivo. Since the isotype determines the effector function, half-life in the serum and distribution throughout the body, it would be useful to have a battery of antibodies with the same binding site associated with different isotypes. However, since hybridomas switch isotypes at very low frequencies in tissue culture, it has been difficult and very labor intensive to isolate panels of class switch variants. We show here that stable transfection of activation-induced cytidine deaminase (AID) in hybridomas increased their frequency of switching to a level that greatly facilitated the isolation of subclones expressing monoclonal antibodies of different isotypes. Although forced expression of AID also increased the frequency of somatic hypermutation in the immunoglobulin variable regions that encode the antigen binding site, antigen recognition was retained in the isotype switched antibodies.
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Affiliation(s)
| | - Manxia Fan
- Department of Cell Biology, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Ziqiang Li
- Department of Cell Biology, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Alberto Martin
- Department of Cell Biology, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Matthew D. Scharff
- Department of Cell Biology, Albert Einstein College of Medicine, Bronx, NY 10461, USA
- Corresponding author. Matthew D. Scharff. Albert Einstein College of Medicine, 1300 Morris Park Avenue, Chanin 403. Bronx, NY 10461, USA. Tel.:+718 430 3527; fax: +718 430 8574. E-mail address:
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Bakkus MH, Asosingh K, Vanderkerken K, Thielemans K, Hagemeijer A, De Raeve H, Van Camp B. Myeloma isotype-switch variants in the murine 5T myeloma model: evidence that myeloma IgM and IgA expressing subclones can originate from the IgG expressing tumour. Leukemia 2001; 15:1127-32. [PMID: 11455984 DOI: 10.1038/sj.leu.2402164] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Isotype-switch variants can easily be detected in a significant proportion of multiple myeloma (MM) patients. The biological significance of these isotype-switch variants remains obscure. Therefore, we studied the appearance of these isotype-switch variants in two murine MM models, 5T2MM and 5T33MM, both of IgG isotype. With a MM-specific PCR assay we could detect isotype-switch variants in the bone marrow of both the 5T2MM and the 5T33MM bearing mice, reflecting again the close resemblance of this mouse model to the human MM. These isotype-switch variants were not found in an in vitro stroma-independent variant of the 5T33MM line. However, when this 5T33MMvitro line was injected into young syngeneic mice, isotype-switch variants appeared thereafter in the isolated tumour cells. These isotype-switch variants could only originate from the MM-IgG expressing cell since IgG subclones from the 5T33MMvitro line again gave rise to isotype-switch variants. The appearance of IgA cells can be explained by down-stream switching of IgG to IgA, while the emergence of IgM cells have to occur via trans-switching to the sister chromatid as the Cmu region is deleted from the CIS-chromosome. This study demonstrates that isotype-switch variants originate from the major tumour clone suggesting no role for the MM-IgM expressing cell as a pre-switch precursor MM cell. The appearance of isotype-switch variants should be considered as a rare but normal event now becoming visible due to the high number of clonal cells present in MM.
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Affiliation(s)
- M H Bakkus
- Department of Haematology and Immunology, KUL, Leuven, Belgium
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Polakova K, Plaksin D, Chung DH, Belyakov IM, Berzofsky JA, Margulies DH. Antibodies directed against the MHC-I molecule H-2Dd complexed with an antigenic peptide: similarities to a T cell receptor with the same specificity. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2000; 165:5703-12. [PMID: 11067928 DOI: 10.4049/jimmunol.165.10.5703] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
alphabeta TCRs, which use an Ab-like structure to form a combining site, recognize molecular complexes consisting of peptides bound to MHC class I (MHC-I) or class II (MHC-II) molecules. To explore the similarities and differences between Ab and T cell recognition of similar structures, we have isolated two mAbs, KP14 and KP15, that specifically bind H-2D(d) complexed with an HIV envelope gp160-derived peptide, P18-I10. These Abs are MHC and peptide specific. Fine specificity of mAb binding was analyzed using a panel of synthetic peptides, revealing similarities between the mAb and a cloned TCR with the same specificity. These two mAbs used the same V(H) and J(H) gene segments, but different D, Vkappa, and Jkappa genes. Administered in vivo, mAb KP15 blocked the induction of CTL specific for recombinant vaccinia virus-encoded gp160, indicating its ability to bind endogenously generated MHC/peptide complexes. Analysis of the fine specificity of these mAbs in the context of their encoded amino acid sequences and the known three-dimensional structure of the H-2D(d)/P18-I10 complex suggests that they bind in an orientation similar to that of the TCR. Thus, the plasticity of the B cell receptor repertoire and the structural similarities among BCR and TCR allow Abs to effectively mimic alphabeta TCRs. Such mAbs may be useful in the therapeutic modulation of immune responses against infectious agents or harmful self Ags as well as in tracing steps in Ag processing.
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MESH Headings
- Amino Acid Sequence
- Animals
- Antibodies, Blocking/pharmacology
- Antibodies, Monoclonal/administration & dosage
- Antibodies, Monoclonal/biosynthesis
- Antibodies, Monoclonal/chemistry
- Antibodies, Monoclonal/metabolism
- Antibody Specificity
- Base Sequence
- Binding Sites, Antibody
- Binding, Competitive/immunology
- Cytotoxicity, Immunologic/immunology
- Epitopes, T-Lymphocyte/metabolism
- H-2 Antigens/immunology
- H-2 Antigens/metabolism
- Histocompatibility Antigen H-2D
- Humans
- Immunosuppressive Agents/administration & dosage
- Immunosuppressive Agents/metabolism
- Immunosuppressive Agents/pharmacology
- Injections, Intraperitoneal
- Jurkat Cells
- Lymphocyte Activation
- Mice
- Mice, Inbred BALB C
- Mice, Inbred C57BL
- Mice, Inbred DBA
- Mice, Transgenic
- Molecular Sequence Data
- Oligopeptides/immunology
- Oligopeptides/metabolism
- Receptors, Antigen, T-Cell, alpha-beta/chemistry
- Receptors, Antigen, T-Cell, alpha-beta/metabolism
- Sequence Homology, Amino Acid
- Structure-Activity Relationship
- Surface Plasmon Resonance
- T-Lymphocytes, Cytotoxic/immunology
- Tumor Cells, Cultured
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Affiliation(s)
- K Polakova
- Molecular Biology Section, Laboratory of Immunology, National Institute of Allergy and Infectious Diseases and Metabolism Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
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Cerutti A, Zan H, Schaffer A, Bergsagel L, Harindranath N, Max EE, Casali P. CD40 Ligand and Appropriate Cytokines Induce Switching to IgG, IgA, and IgE and Coordinated Germinal Center and Plasmacytoid Phenotypic Differentiation in a Human Monoclonal IgM+IgD+ B Cell Line. THE JOURNAL OF IMMUNOLOGY 1998. [DOI: 10.4049/jimmunol.160.5.2145] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Abstract
B lymphocytes are induced to undergo Ig class switching and a complex phenotypic differentiation by the milieu of the germinal center. Partly as a result of the lack of a suitable in vitro B cell model, the relationship between these processes in the humans has never been formally established in vitro. We have identified a human monoclonal B cell line, CL-01, that expresses surface IgM and IgD and, upon induction with CD40 ligand, IL-4, and IL-10, switches to all seven downstream isotypes, showing typical DNA switch recombination preceded by germline transcription of targeted CH regions. In CL-01 cells, switch-inducing stimuli trigger concomitant changes in expression of surface IgD, CD23, CD38, and CD77 that parallel those reported in ex vivo isolated tonsillar centroblasts, centrocytes, and memory B cells. Eventually, in the presence of IL-6, CL-01 cells express CD56 and accumulate cytoplasmic IgG and IgA, both traits of plasmacytoid differentiation. Analysis of transcription and recombination of the Ig H locus in sorted CL-01 cells suggest that Ig class switching begins in centroblasts, it extends to all isotypes in centrocytes, and it is extinct in memory B cells. Thus, we have induced coordinated Ig class switching, progression through germinal center phenotypic stages, and differentiation to memory B cells and plasma cells at the level of a single B clonotype. Our data suggest that these processes are likely regulated by a common maturation program, the activation of which may require CD40 ligand, IL-4, IL-10, and IL-6 only.
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Affiliation(s)
- Andrea Cerutti
- *Division of Molecular Immunology, Department of Pathology,
| | - Hong Zan
- *Division of Molecular Immunology, Department of Pathology,
| | - Andras Schaffer
- *Division of Molecular Immunology, Department of Pathology,
- †The Immunology Program, Cornell University Graduate School of Medical Sciences, and
| | - Leif Bergsagel
- ‡Division of Hematology, Department of Internal Medicine, Cornell University Medical College, New York, NY 10021; and
| | - Nagaradona Harindranath
- §Center for Biologics Evaluation and Research, Food and Drug Administration, Bethesda, MD 20892
| | - Edward E. Max
- §Center for Biologics Evaluation and Research, Food and Drug Administration, Bethesda, MD 20892
| | - Paolo Casali
- *Division of Molecular Immunology, Department of Pathology,
- †The Immunology Program, Cornell University Graduate School of Medical Sciences, and
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Cerutti A, Zan H, Schaffer A, Bergsagel L, Harindranath N, Max EE, Casali P. CD40 ligand and appropriate cytokines induce switching to IgG, IgA, and IgE and coordinated germinal center and plasmacytoid phenotypic differentiation in a human monoclonal IgM+IgD+ B cell line. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 1998; 160:2145-57. [PMID: 9498752 PMCID: PMC4624333] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
B lymphocytes are induced to undergo Ig class switching and a complex phenotypic differentiation by the milieu of the germinal center. Partly as a result of the lack of a suitable in vitro B cell model, the relationship between these processes in the humans has never been formally established in vitro. We have identified a human monoclonal B cell line, CL-01, that expresses surface IgM and IgD and, upon induction with CD40 ligand, IL-4, and IL-10, switches to all seven downstream isotypes, showing typical DNA switch recombination preceded by germline transcription of targeted CH regions. In CL-01 cells, switch-inducing stimuli trigger concomitant changes in expression of surface IgD, CD23, CD38, and CD77 that parallel those reported in ex vivo isolated tonsillar centroblasts, centrocytes, and memory B cells. Eventually, in the presence of IL-6, CL-01 cells express CD56 and accumulate cytoplasmic IgG and IgA, both traits of plasmacytoid differentiation. Analysis of transcription and recombination of the Ig H locus in sorted CL-01 cells suggest that Ig class switching begins in centroblasts, it extends to all isotypes in centrocytes, and it is extinct in memory B cells. Thus, we have induced coordinated Ig class switching, progression through germinal center phenotypic stages, and differentiation to memory B cells and plasma cells at the level of a single B clonotype. Our data suggest that these processes are likely regulated by a common maturation program, the activation of which may require CD40 ligand, IL-4, IL-10, and IL-6 only.
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Affiliation(s)
- Andrea Cerutti
- Division of Molecular Immunology, Department of Pathology, Cornell University Medical College, New York, NY 10021
| | - Hong Zan
- Division of Molecular Immunology, Department of Pathology, Cornell University Medical College, New York, NY 10021
| | - Andras Schaffer
- Division of Molecular Immunology, Department of Pathology, Cornell University Medical College, New York, NY 10021
- The Immunology Program, Cornell University Graduate School of Medical Sciences, Cornell University Medical College, New York, NY 10021
| | - Leif Bergsagel
- Division of Hematology, Department of Internal Medicine, Cornell University Medical College, New York, NY 10021
| | - Nagaradona Harindranath
- Center for Biologics Evaluation and Research, Food and Drug Administration, Bethesda, MD 20892
| | - Edward E. Max
- Center for Biologics Evaluation and Research, Food and Drug Administration, Bethesda, MD 20892
| | - Paolo Casali
- Division of Molecular Immunology, Department of Pathology, Cornell University Medical College, New York, NY 10021
- The Immunology Program, Cornell University Graduate School of Medical Sciences, Cornell University Medical College, New York, NY 10021
- Address correspondence and reprint requests to Dr. Paolo Casali, Division of Molecular Immunology, Department of Pathology (C-312), Cornell University Medical College, 1300 York Avenue, New York, NY 10021.
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11
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Bergsagel PL, Chesi M, Nardini E, Brents LA, Kirby SL, Kuehl WM. Promiscuous translocations into immunoglobulin heavy chain switch regions in multiple myeloma. Proc Natl Acad Sci U S A 1996; 93:13931-6. [PMID: 8943038 PMCID: PMC19472 DOI: 10.1073/pnas.93.24.13931] [Citation(s) in RCA: 281] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
In multiple myeloma, karyotopic 14q32 translocations have been identified at a variable frequency (10-60% in different studies). In the majority of cases, the partner chromosome has not been identified (14q+), and in the remaining cases, a diverse array of chromosomal partners has been implicated, with 11q13 being the most common. We developed a comprehensive Southern blot assay to identify and distinguish different kinds of immunoglobulin heavy chain (IgH) switch recombination events. Illegitimate switch recombination fragments (defined as containing sequences from only one switch region) are potential markers of translocation events into IgH switch regions and were identified in 15 of 21 myeloma cell lines, including seven of eight karyotyped lines that have no detectable 14q32 translocation. From all nine lines or tumor samples analyzed further, cloned illegitimate switch recombination fragments were confirmed to be IgH switch translocation breakpoints. In three of these cases, the translocation breakpoint was shown to be present in the primary tumor. These translocation breakpoints involve six chromosomal loci: 4p16.3 (two lines and the one tumor); 6; 8q24.13; 11q13.3 (in three lines); 16q23.1; and 21q22.1. We suggest that translocations into the IgH locus (i) are frequent (karyotypic 14q32 translocations and/or illegitimate switch recombination fragments are present in primary tumor samples and in 19 of 21 lines that we have analyzed); (ii) occur mainly in switch regions; and (iii) involve a diverse but nonrandom array (i.e., frequently 11q13 or 4p16) of chromosomal partners. This appears to be the most frequent genetic abnormality in multiple myeloma.
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Affiliation(s)
- P L Bergsagel
- Cornell University Medical College, New York, NY 10021, USA
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12
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Lin M, Spira G, Scharff MD. Molecular comparison of cultured hybridoma cells that switch isotypes at high and low rates. SOMATIC CELL AND MOLECULAR GENETICS 1996; 22:329-40. [PMID: 9000175 DOI: 10.1007/bf02369570] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
We have previously reported the isolation of variants from the 36.65 and PC1.4.1 hybridoma cell lines that spontaneously switch from gamma 1 to gamma 2a and gamma 2b at high and low rates. In order to further characterize the phenotype of these variants, we have now investigated the production of germline transcripts and methylation which are two of the molecular correlates of isotype switching. While some of the correlations that exist in normal cells were present in some of the clonal variants, others were not. However, the higher switching variants of both cells lines had higher recombinational activity as measured with a shuttle vector. The distinct phenotypic characteristics of each cell line provide an opportunity to dissect the roles of individual molecular events in the process of isotype switching.
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Affiliation(s)
- M Lin
- Department of Cell Biology, Albert Einstein College of Medicine, Bronx, New York 10461, USA
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13
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Affiliation(s)
- J Stavnezer
- Department of Molecular Genetics and Microbiology, University of Massachusetts Medical School, Worcester 01655-0122, USA
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14
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Paizi M, Zivion D, Spira G. Use of mutagens to increase rate of immunoglobulin isotype switching of hybridoma cells. Hybridoma (Larchmt) 1995; 14:85-90. [PMID: 7768537 DOI: 10.1089/hyb.1995.14.85] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Isotype switching of hybridoma clones may be essential when the class of the antibody produced does not suit the task for which it was generated. In those instances immunoglobulin (Ig) switch variants can be isolated in vitro but the success of isolating these rare variants primarily depends on the frequency of switching of each individual hybridoma. Variations in the frequency are noted not only between hybridomas secreting different classes but also between fresh clones isolated from the same hybridoma. Immunoglobulin switch variants may be identified and isolated using the sib selection and the ELISA spot assay; however, when the frequency of switching is low, this may be extremely difficult and sometimes impossible. In the present article we demonstrate that ICR191 may increase the frequency of switching and that these Ig switch antibodies maintain the same antigen specificity and normal-sized heavy chain.
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Affiliation(s)
- M Paizi
- Laboratory of Cell Biology, Rappaport Family Institute for Research in the Medical Sciences, Haifa, Israel
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