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Wallaschek N, Reuter S, Silkenat S, Wolf K, Niklas C, Kayisoglu Ö, Aguilar C, Wiegering A, Germer CT, Kircher S, Rosenwald A, Shannon-Lowe C, Bartfeld S. Ephrin receptor A2, the epithelial receptor for Epstein-Barr virus entry, is not available for efficient infection in human gastric organoids. PLoS Pathog 2021; 17:e1009210. [PMID: 33596248 PMCID: PMC7935236 DOI: 10.1371/journal.ppat.1009210] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Revised: 03/05/2021] [Accepted: 12/02/2020] [Indexed: 12/12/2022] Open
Abstract
Epstein-Barr virus (EBV) is best known for infection of B cells, in which it usually establishes an asymptomatic lifelong infection, but is also associated with the development of multiple B cell lymphomas. EBV also infects epithelial cells and is associated with all cases of undifferentiated nasopharyngeal carcinoma (NPC). EBV is etiologically linked with at least 8% of gastric cancer (EBVaGC) that comprises a genetically and epigenetically distinct subset of GC. Although we have a very good understanding of B cell entry and lymphomagenesis, the sequence of events leading to EBVaGC remains poorly understood. Recently, ephrin receptor A2 (EPHA2) was proposed as the epithelial cell receptor on human cancer cell lines. Although we confirm some of these results, we demonstrate that EBV does not infect healthy adult stem cell-derived gastric organoids. In matched pairs of normal and cancer-derived organoids from the same patient, EBV only reproducibly infected the cancer organoids. While there was no clear pattern of differential expression between normal and cancer organoids for EPHA2 at the RNA and protein level, the subcellular location of the protein differed markedly. Confocal microscopy showed EPHA2 localization at the cell-cell junctions in primary cells, but not in cancer cell lines. Furthermore, histologic analysis of patient tissue revealed the absence of EBV in healthy epithelium and presence of EBV in epithelial cells from inflamed tissue. These data suggest that the EPHA2 receptor is not accessible to EBV on healthy gastric epithelial cells with intact cell-cell contacts, but either this or another, yet to be identified receptor may become accessible following cellular changes induced by inflammation or transformation, rendering changes in the cellular architecture an essential prerequisite to EBV infection.
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Affiliation(s)
- Nina Wallaschek
- Research Centre for Infectious Diseases, Institute for Molecular Infection Biology, Julius Maximilian University of Wuerzburg, Wuerzburg, Germany
| | - Saskia Reuter
- Research Centre for Infectious Diseases, Institute for Molecular Infection Biology, Julius Maximilian University of Wuerzburg, Wuerzburg, Germany
| | - Sabrina Silkenat
- Research Centre for Infectious Diseases, Institute for Molecular Infection Biology, Julius Maximilian University of Wuerzburg, Wuerzburg, Germany
| | - Katharina Wolf
- Research Centre for Infectious Diseases, Institute for Molecular Infection Biology, Julius Maximilian University of Wuerzburg, Wuerzburg, Germany
| | - Carolin Niklas
- Research Centre for Infectious Diseases, Institute for Molecular Infection Biology, Julius Maximilian University of Wuerzburg, Wuerzburg, Germany
| | - Özge Kayisoglu
- Research Centre for Infectious Diseases, Institute for Molecular Infection Biology, Julius Maximilian University of Wuerzburg, Wuerzburg, Germany
| | - Carmen Aguilar
- Research Centre for Infectious Diseases, Institute for Molecular Infection Biology, Julius Maximilian University of Wuerzburg, Wuerzburg, Germany
| | - Armin Wiegering
- Department of General, Visceral, Vascular and Paediatric Surgery, University Hospital of Wuerzburg, Wuerzburg, Germany
| | - Christoph-Thomas Germer
- Department of General, Visceral, Vascular and Paediatric Surgery, University Hospital of Wuerzburg, Wuerzburg, Germany
| | - Stefan Kircher
- Institute of Pathology, Julius Maximilian University of Wuerzburg and Comprehensive Cancer Center Mainfranken, Wuerzburg, Germany
| | - Andreas Rosenwald
- Institute of Pathology, Julius Maximilian University of Wuerzburg and Comprehensive Cancer Center Mainfranken, Wuerzburg, Germany
| | - Claire Shannon-Lowe
- Institute of Immunology and Immunotherapy, University of Birmingham, Birmingham, United Kingdom
| | - Sina Bartfeld
- Research Centre for Infectious Diseases, Institute for Molecular Infection Biology, Julius Maximilian University of Wuerzburg, Wuerzburg, Germany
- * E-mail: ,
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2
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London M, Gallo E. The EphA2 and cancer connection: potential for immune-based interventions. Mol Biol Rep 2020; 47:8037-8048. [PMID: 32990903 DOI: 10.1007/s11033-020-05767-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Accepted: 08/28/2020] [Indexed: 12/18/2022]
Abstract
The Eph (erythropoietin-producing human hepatocellular) receptors form the largest known subfamily of receptor tyrosine kinases. These receptors interact with membrane-bound ephrin ligands via direct cell-cell interactions resulting in bi-directional activation of signal pathways. Importantly, the Eph receptors play critical roles in embryonic tissue organization and homeostasis, and in the maintenance of adult processes such as long-term potentiation, angiogenesis, and stem cell differentiation. The Eph receptors also display properties of both tumor promoters and suppressors depending on the cellular context. Characterization of EphA2 receptor in regard to EphA2 dysregulation has revealed associations with various pathological processes, especially cancer. The analysis of various tumor types generally identify EphA2 receptor as overexpressed and/or mutated, and for certain types of cancers EphA2 is linked with poor prognosis and decreased patient survival. Thus, here we highlight the role of EphA2 in malignant tissues that are specific to cancer; these include glioblastoma multiforme, prostate cancer, ovarian and uterine cancers, gastric carcinoma, melanoma, and breast cancer. Due to its large extracellular domain, therapeutic targeting of EphA2 with monoclonal antibodies (mAbs), which may function as inhibitors of ligand activation or as molecular agonists, has been an oft-attempted strategy. Therefore, we review the most current mAb-based therapies against EphA2 expressing cancers currently in pre-clinical and/or clinical stages. Finally, we discuss the latest peptides and cyclical-peptides that function as selective agonists for EphA2 receptor.
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Affiliation(s)
- Max London
- Department of Molecular Genetics, University of Toronto, Donnelly Centre, 160 College Street, Toronto, ON, M5S 3E1, Canada
| | - Eugenio Gallo
- Department of Molecular Genetics, University of Toronto, Donnelly Centre, 160 College Street, Toronto, ON, M5S 3E1, Canada.
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3
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Fedor-Chaiken M, Hein PW, Stewart JC, Brackenbury R, Kinch MS. E-Cadherin Binding Modulates EGF Receptor Activation. ACTA ACUST UNITED AC 2009. [DOI: 10.1080/cac.10.2.105.118] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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4
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Zabell KM, Laurence JS, Kinch MS, Knapp DW, Stauffacher CV. Expression and purification of the intact cytoplasmic domain of the human ephrin receptor A2 tyrosine kinase in Escherichia coli. Protein Expr Purif 2006; 47:210-6. [PMID: 16426859 DOI: 10.1016/j.pep.2005.10.031] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2005] [Revised: 10/24/2005] [Accepted: 10/25/2005] [Indexed: 12/01/2022]
Abstract
The ephrin receptor A2 (EphA2) is an integral membrane protein tyrosine kinase and a member of the Eph family, the largest known family of receptor tyrosine kinases. EphA2 overexpression is sufficient to transform normal epithelial cells into an aggressive, metastatic phenotype. In normal cells, EphA2 negatively regulates cell growth and invasiveness. Here we report expression of the intact cytoplasmic domain (juxtamembrane linker, tyrosine kinase, and sterile alpha motif domains) of the human EphA2 receptor in an Escherichia coli system. The expressed protein was purified to near homogeneity by use of metal chelation chromatography combined with removal of vector-encoded tags by specific proteolysis. The cytoplasmic domains of EphA2 are expressed as an active kinase, with the expressed protein found to contain phosphorylated tyrosine residues. In addition, protein tyrosine phosphorylation appears only after EphA2 expression is induced and is removable with alkaline phosphatase treatment. The enzyme was purified 5-fold in yields that average 10-30 mg/L of active EphA2 cytoplasmic domains, which will now be used for further biophysical and structural characterization.
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Affiliation(s)
- Kathryn M Zabell
- Department of Biological Sciences, Purdue University, West Lafayette, IN 47907, USA
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5
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Chen C, Patel S, Corisdeo S, Liu X, Micolochick H, Xue J, Yang Q, Lei Y, Wang B, Soltis D. Generation and Characterization of a Panel of Monoclonal Antibodies Specific for Human Fibroblast Growth Factor Receptor 4 (FGFR4). Hybridoma (Larchmt) 2005; 24:152-9. [PMID: 15943563 DOI: 10.1089/hyb.2005.24.152] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Fibroblast growth factor receptor 4 (FGFR4) is a member of the FGFR family of receptor tyrosine kinases, and plays important roles in a variety of biological functions such as cell proliferation, differentiation, migration, angiogenesis, tissue repair, and tumorigenesis. The human FGFRs share a high degree of sequence homology between themselves, as well as with their murine homologs. Consequently, it has been suggested that it may be difficult to prepare monoclonal antibodies (MAbs) that are specific for the individual receptor types. In this communication, we report on the development and characterization of a panel of anti-human FGFR4 MAbs that were generated in mice using a rapid immunization protocol. Using a modified rapid immunization at multiple sites (RIMMS) protocol with the soluble extracellular domain of human FGFR4 (FGFR4-ECD), the immunized mice developed high levels of polyclonal IgG to the immunogen within 13 days of the first immunization. The lymph node cells isolated from the immunized animals were then fused with mouse myeloma cells for hybridoma generation. Use of an efficient hybridoma cloning protocol in combination with an ELISA screening procedure allowed for early identification of stable hybridomas secreting antihuman FGFR4 IgG. Several identified MAbs specifically reacted with the FGFR4 protein without binding to the other human isoforms (FGFR1, FGFR2, and FGFR3). As evaluated by BIAcore analysis, most anti-FGFR4 MAbs displayed high affinities (8.6 x 10(8) approximately 3.9 x 10(10) M) to FGFR4. Furthermore, these MAbs were able to bind to FGFR4 expressed on human breast tumor cell lines MDA-MB-361 and MDA-MB-453. Taken together, the results demonstrate that the RIMMS strategy is an effective approach for generating class-switched, high-affinity MAbs in mice to evolutionarily conserved proteins such as human FGFR4. These MAbs may be useful tools for further investigation of the biological functions and pathological roles of human FGFR4.
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Affiliation(s)
- Chaoyuan Chen
- Department of Immunotherapeutics, Discovery Research, Purdue Pharma, LP, Cranbury, New Jersey, USA.
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Noblitt LW, Bangari DS, Shukla S, Knapp DW, Mohammed S, Kinch MS, Mittal SK. Decreased tumorigenic potential of EphA2-overexpressing breast cancer cells following treatment with adenoviral vectors that express EphrinA1. Cancer Gene Ther 2005; 11:757-66. [PMID: 15359289 DOI: 10.1038/sj.cgt.7700761] [Citation(s) in RCA: 91] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The EphA2 receptor tyrosine kinase is frequently overexpressed in invasive breast cancer cells. Moreover, these malignant cells have unstable cell-cell contacts, which preclude EphA2 from interacting with its ligand, EphrinA1, which is anchored to the membrane of adjacent cells. This defect is important because ligand binding causes EphA2 to transmit signals that negatively regulate tumor cell growth and survival, whereas the absence of ligand binding favors these same behaviors. In our present study, human adenoviral type 5 (HAd) vectors were engineered to express secreted-forms of EphrinA1. These vectors were used to infect MDA-MB-231 human breast cancer cells, or MCF-10A human breast epithelial cells providing matched controls. Infection with HAd-EphrinA1-Fc (HAd vector expressing extracellular domain of human EphrinA1 attached to Fc portion of human IgG1 heavy chain) caused increased EphA2 activation and turnover and consequently decreased tumor cell viability in soft agar assays. Consistent with this observation, infection of MDA-MB-231 cells with HAd-EphrinA1-Fc prevented tumor formation in xenograft models. Furthermore, therapeutic modeling via intratumoral inoculation revealed that HAd-EphrinA1-Fc significantly inhibited subsequent tumor growth as compared to matched controls. These results suggest that targeting of EphA2 with adenoviral vectors may have therapeutic value.
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Affiliation(s)
- Loren W Noblitt
- Laboratory of Gene Therapy, Purdue University, West Lafayette, Indiana 47907, USA
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Chen C, Yang Q, Patel S, Lei Y, McAleer L, Singleton J, Soltis D, Wang B. Characterization of Human Tissue Factor (TF)–Specific Monoclonal Antibodies Prepared Using a Rapid Immunization Protocol. Hybridoma (Larchmt) 2005; 24:78-85. [PMID: 15857171 DOI: 10.1089/hyb.2005.24.78] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Tissue factor (TF) plays an important, physiological role in hemostasis. Recent studies have demonstrated the over-expression of TF in a number of solid tumor types and its pathological roles in angiogenesis and tumor metastasis. In this study, we report the development and characterization of a panel of murine MAbs that are specific for human TF, but do not inhibit TF-mediated blood coagulation. By using a modified repetitive immunizations at multiple sites (RIMMS) protocol in conjunction with an efficient hybridoma cloning procedure, anti-TF MAbs were generated within a relatively short time frame of 5-6 weeks. Following primary screening by ELISA, the binding of the MAbs to the native form of human TF was demonstrated in flow cytometry using a stable cell line expressing human TF. Several of these TF-specific MAbs did not inhibit blood coagulation in a blood coagulation assay and bound with high affinity (0.5-2 nM) to human TF in BIAcore analyses. Importantly, this study represents an independent evaluation of the RIMMS strategy for MAb generation and demonstrates that class-switched, high-affinity MAbs can be generated rapidly and reliably using RIMMS.
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Affiliation(s)
- Chaoyuan Chen
- Department of Immunotherapeutics, Purdue Pharma L.P., Cranbury, New Jersey, USA
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8
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Kinch MS, Carles-Kinch K. Overexpression and functional alterations of the EphA2 tyrosine kinase in cancer. Clin Exp Metastasis 2003; 20:59-68. [PMID: 12650608 DOI: 10.1023/a:1022546620495] [Citation(s) in RCA: 107] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Cancer is a disease of aberrant signal transduction. The expression and function of intracellular signaling pathways are frequently subverted as cells progress towards a metastatic phenotype. In particular, tyrosine kinases initiate powerful signals that govern many different aspects of cell behavior. In Recent studies have demonstrated that the EphA2 receptor tyrosine kinase is frequently overexpressed and functionally altered in aggressive tumor cells, and that these changes promote metastatic character. Herein, we provide an overview of our current understanding of EphA2, with emphasis upon the differential regulation of EphA2 expression and function. We also show that differential EphA2 expression and function may provide a unique opportunity for selective therapeutic targeting of EphA2 in metastatic disease.
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Kilpatrick KE, Kerner S, Dixon EP, Hutchins JT, Parham JH, Condreay JP, Pahel G. In vivo expression of a GST-fusion protein mediates the rapid generation of affinity matured monoclonal antibodies using DNA-based immunizations. HYBRIDOMA AND HYBRIDOMICS 2002; 21:237-43. [PMID: 12193276 DOI: 10.1089/153685902760213840] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Previously we demonstrated the rapid generation of affinity matured monoclonal antibody (MAb) producing cell lines following gene gun delivery of DNA using a mammalian expression vector (pAlpha/hFc), which enables the expression of human Fc-chimera proteins in vivo. Here we compare the pAlpha/hFc vector to modified vectors that replace human IgG(1) with either a Glutathione-S-Transferase (GST) fusion protein or a mouse IgG(2c) (mFc) fusion protein. We report that in vivo expression of a GST-chimera results in the rapid generation of affinity matured MAbs, comparable with antibodies raised using the pAlpha/hFc vector, that were reactive with annexin V. The mFc vector failed to induce early antigen-specific B-cell responses suitable for MAb development.
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10
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Alligood KJ, Milla M, Rhodes N, Ellis B, Kilpatrick KE, Lee A, Gilmer TM, Lansing TJ. Monoclonal antibodies generated against recombinant ATM support kinase activity. Hybridoma (Larchmt) 2000; 19:317-21. [PMID: 11001404 DOI: 10.1089/027245700429864] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
We report on the rapid generation of two monoclonal antibodies, ATM A16.35 and ATM D16.11, that bind to the kinase domain of mutated ataxia telangiectasia (ATM). These antibodies were generated against E. coli-expressed recombinant protein using the RIMMS strategy. We show that ATM A16.35 binds ATM by Western blot analysis, and ATM D16.11 forms immune complexes with native ATM in immunoprecipitations without neutralizing kinase activity.
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Affiliation(s)
- K J Alligood
- Department of Cancer Biology, Glaxo Welcome Research and Development, Research Triangle Park, NC 27709-3398,USA
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11
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Walker-Daniels J, Coffman K, Azimi M, Rhim JS, Bostwick DG, Snyder P, Kerns BJ, Waters DJ, Kinch MS. Overexpression of the EphA2 tyrosine kinase in prostate cancer. Prostate 1999; 41:275-80. [PMID: 10544301 DOI: 10.1002/(sici)1097-0045(19991201)41:4<275::aid-pros8>3.0.co;2-t] [Citation(s) in RCA: 195] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
BACKGROUND Molecules that are highly expressed by human prostate cancers may serve as therapeutically relevant targets or tumor markers. Tyrosine kinases are frequently overexpressed in metastatic tumor cells and this prompted us to screen for tyrosine kinases that are overexpressed in prostate cancer cells. METHODS Expression levels of the EphA2 receptor tyrosine kinase were determined by Western blot analysis in canine and human prostate cancer cell lines and in immortalized and transformed variants of 267B1 prostatic epithelial cells. EphA2 levels in benign human prostate and prostate cancers were also determined in formalin-fixed, paraffin-embedded tissues using immunohistochemical staining. RESULTS Metastatic prostate cancer cells overexpressed EphA2 by 10-100 fold as compared with non-invasive prostatic epithelial cells. EphA2 immunoreactivity in vivo was also significantly greater in human prostate cancers as compared with benign prostate epithelium. CONCLUSIONS The EphA2 receptor tyrosine kinase is differentially expressed in human and canine prostate cancer cell lines and overexpressed in human prostate cancers as compared with benign prostate tissues. Metastasis-derived canine prostate carcinoma cell lines overexpress EphA2 and may provide pre-clinical models to further evaluate the role of EphA2 in prostate carcinogenesis. Further investigations are needed to determine the utility of EphA2 as a tumor marker and a novel target in human prostate cancer.
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Affiliation(s)
- J Walker-Daniels
- Department of Basic Medical Sciences, Purdue University, West Lafayette, Indiana 47907-1246, USA
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12
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Bynum J, Andrews JL, Ellis B, Kull FC, Austin EA, Kilpatrick KE. Development of class-switched, affinity-matured monoclonal antibodies following a 7-day immunization schedule. Hybridoma (Larchmt) 1999; 18:407-11. [PMID: 10600027 DOI: 10.1089/hyb.1999.18.407] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Previously we reported making high-affinity monoclonal antibodies (MAbs) 13 days after the onset of Repetitive Immunizations Multiple Sites (RIMMS) strategy. The Ig subclass variety and affinity of these antibodies suggested that maturational processes had already begun within draining lymph nodes. We now demonstrate that this diversity can in fact be captured as early as Day 7. In the work reported here, somatic fusion of immune lymphocytes isolated from peripheral lymph nodes resulted in the isolation of affinity-matured MAbs reactive with cytosine deaminase. This model further demonstrates and substantiates at a cellular level the rapid development and maturation of T-cell-dependent B-cell responses occurring within draining lymph nodes following antigen challenge.
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Affiliation(s)
- J Bynum
- Department of Molecular Sciences, Glaxo Wellcome, Research Triangle Park, NC 27709, USA
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13
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Wring SA, Kilpatrick KE, Hutchins JT, Witherspoon SM, Ellis B, Jenner WN, Serabjit-Singh C. Shorter development of immunoassay for drugs: application of the novel RIMMS technique enables rapid production of monoclonal antibodies to ranitidine. J Pharm Biomed Anal 1999; 19:695-707. [PMID: 10698534 DOI: 10.1016/s0731-7085(98)00296-9] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
High affinity, specific murine monoclonal antibodies have been produced for ranitidine using the novel RIMMS (repetitive immunizations, multiple sites) technique. We demonstrate that this technique can be employed to produce high affinity monoclonal antibodies to drug haptens in approximately 1 month; whereas, conventional techniques typically require 3-9 months. Polyclonal antiserum development typically requires at least 6 months. Consequently, RIMMS has a clear impact allowing reagent antibodies to be available earlier in the drug development process. Isotyping studies demonstrated that the developed antibodies are either IgG1 or IgG2b immunoglobulins which confirms that the technique produces class-switched, affinity matured reagent antibodies. The most promising monoclonal antibody for quantitative applications afforded similar sensitivity, by competitive ELISA, to the established sheep polyclonal anti-ranitidine sera. The calibration range, estimated as the limits between the asymptotic regions of calibration graphs, is 0.5-41.2 ng ranitidine per well. Specificity studies indicated that the monoclonal antibody afforded superior selectivity, yielding only 4.1% cross-reactivity with the ranitidine sulphoxide metabolite; the corresponding value for the antiserum was 8.6%. Both reagents had similar cross-reactivities with the N-oxide metabolite.
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Affiliation(s)
- S A Wring
- Bioanalysis and Drug Metabolism Division, Glaxo Wellcome Research Inc., Research Triangle Park, NC 27709, USA.
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Kilpatrick KE, Cutler T, Whitehorn E, Drape RJ, Macklin MD, Witherspoon SM, Singer S, Hutchins JT. Gene gun delivered DNA-based immunizations mediate rapid production of murine monoclonal antibodies to the Flt-3 receptor. Hybridoma (Larchmt) 1998; 17:569-76. [PMID: 9890713 DOI: 10.1089/hyb.1998.17.569] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Class-switched, affinity-matured murine monoclonal antibody (MAb)-producing cell lines were generated against the Flt-3 receptor in less than 4 weeks following polynucleotide immunizations, used in conjunction with repetitive immunizations, multiple sites (RIMMS). Plasmid DNA encoding Flt-3/Fc was coated onto gold particles, which were subsequently propelled into the epidermis of mice using biolistic particle bombardment using the Accell gene gun. Pools of immune peripheral lymph node cells were somatically fused 13 days after the onset of delivery of DNA encoding the target antigen. To determine if early responses could be augmented, DNA-encoding murine GM-CSF was delivered 3 days prior to the Flt-3/Fc DNA immunizations. The data presented demonstrates the successful identification and characterization of class-switched, affinity-matured MAbs that bind to the Flt-3 receptor. When compared to conventional methodologies or intramuscular targeted DNA-based immunization for the generation of MAbs, use of the gene gun in conjunction with RIMMS allows for a more rapid production of affinity-matured MAb-producing cell lines.
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Affiliation(s)
- K E Kilpatrick
- Department of Molecular Sciences, Glaxo Wellcome, Research Triangle Park, NC 27709, USA
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