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Okada Y, Suzuki H, Tanaka T, Kaneko MK, Kato Y. Epitope Mapping of an Anti-Mouse CD39 Monoclonal Antibody Using PA Scanning and RIEDL Scanning. Monoclon Antib Immunodiagn Immunother 2024; 43:44-52. [PMID: 38507671 DOI: 10.1089/mab.2023.0029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/22/2024] Open
Abstract
A cell-surface ectonucleotidase CD39 mediates the conversion of extracellular adenosine triphosphate into immunosuppressive adenosine with another ectonucleotidase CD73. The elevated adenosine in the tumor microenvironment attenuates antitumor immunity, which promotes tumor cell immunologic escape and progression. Anti-CD39 monoclonal antibodies (mAbs), which suppress the enzymatic activity, can be applied to antitumor therapy. Therefore, an understanding of the relationship between the inhibitory activity and epitope of mAbs is important. We previously established an anti-mouse CD39 (anti-mCD39) mAb, C39Mab-1 using the Cell-Based Immunization and Screening method. In this study, we determined the critical epitope of C39Mab-1 using flow cytometry. We performed the PA tag (12 amino acids [aa])-substituted analysis (named PA scanning) and RIEDL tag (5 aa)-substituted analysis (named RIEDL scanning) to determine the critical epitope of C39Mab-1 using flow cytometry. By the combination of PA scanning and RIEDL scanning, we identified the conformational epitope, spanning three segments of 275-279, 282-291, and 306-323 aa of mCD39. These analyses would contribute to the identification of the conformational epitope of membrane proteins.
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Affiliation(s)
- Yuki Okada
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan
| | - Hiroyuki Suzuki
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan
| | - Tomohiro Tanaka
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan
| | - Mika K Kaneko
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan
| | - Yukinari Kato
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan
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2
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Nanamiya R, Suzuki H, Takei J, Li G, Goto N, Harada H, Saito M, Tanaka T, Asano T, Kaneko MK, Kato Y. Development of Monoclonal Antibody 281-mG 2a-f Against Golden Hamster Podoplanin. Monoclon Antib Immunodiagn Immunother 2022; 41:311-319. [PMID: 35483059 DOI: 10.1089/mab.2021.0058] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Golden (Syrian) hamster (Mesocricetus auratus) is a small animal model of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections. Pathological analyses of the tissues are required to understand the pathogenesis of SARS-CoV-2 and the evaluation of therapeutic modalities, including neutralizing monoclonal antibodies (mAbs). However, mAbs that recognize the golden hamster-derived antigens and distinguish specific cell types, such as the pneumocytes, are limited. Podoplanin (PDPN) is an essential marker of lung type I alveolar epithelial cells, kidney podocytes, and lymphatic endothelial cells. In this study, an anti-Chinese hamster (Cricetulus griseus) PDPN mAb PMab-281 (IgG3, kappa) was established using the Cell-Based Immunization and Screening (CBIS) method. A defucosylated mouse IgG2a version of PMab-281 (281-mG2a-f) was also developed. The 281-mG2a-f strongly recognized both the Chinese hamster and the golden hamster PDPN using flow cytometry and could detect lung type I alveolar epithelial cells, lymphatic endothelial cells, and Bowman's capsules in the kidney from the golden hamster using immunohistochemistry. These results suggest the usefulness of 281-mG2a-f for analyzing the golden hamster-derived tissues and cells for SARS-CoV-2 research.
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Affiliation(s)
- Ren Nanamiya
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Hiroyuki Suzuki
- Department of Molecular Pharmacology, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Junko Takei
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Japan.,Department of Oral and Maxillofacial Surgery, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Bunkyo-ku, Japan
| | - Guanjie Li
- Department of Molecular Pharmacology, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Nohara Goto
- Department of Molecular Pharmacology, Tohoku University Graduate School of Medicine, Sendai, Japan.,Department of Experimental Pathology, Graduate School of Comprehensive Human Sciences, Faculty of Medicine, University of Tsukuba, Tsukuba, Japan
| | - Hiroyuki Harada
- Department of Oral and Maxillofacial Surgery, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Bunkyo-ku, Japan
| | - Masaki Saito
- Department of Molecular Pharmacology, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Tomohiro Tanaka
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Teizo Asano
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Mika K Kaneko
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Yukinari Kato
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Japan.,Department of Molecular Pharmacology, Tohoku University Graduate School of Medicine, Sendai, Japan
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Goto N, Suzuki H, Tanaka T, Asano T, Kaneko MK, Kato Y. Development of a Monoclonal Antibody PMab-292 Against Ferret Podoplanin. Monoclon Antib Immunodiagn Immunother 2022; 41:101-109. [PMID: 35471053 DOI: 10.1089/mab.2021.0067] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Ferrets (Mustela putorius furo) have been used as small animal models to investigate severe acute respiratory syndrome coronaviruses (SARS-CoV and SARS-CoV-2) infections. Pathological analyses of these tissue samples, including those of the lung, are, therefore, essential to understand the pathogenesis of SARS-CoVs and evaluate the action of therapeutic monoclonal antibodies (mAbs) against this disease. However, mAbs that recognize ferret-derived proteins and distinguish between specific cell types, such as lung epithelial cells, are limited. Podoplanin (PDPN) has been identified as an essential marker in lung type I alveolar epithelial cells, kidney podocytes, and lymphatic endothelial cells. In this study, an anti-ferret PDPN (ferPDPN) mAb PMab-292 (mouse IgG1, kappa) was established using the Cell-Based Immunization and Screening (CBIS) method. PMab-292 recognized ferPDPN-overexpressed Chinese hamster ovary-K1 (CHO/ferPDPN) cells by flow cytometry and Western blotting. The kinetic analysis using flow cytometry showed that the KD of PMab-292 for CHO/ferPDPN was 3.4 × 10-8 M. Furthermore, PMab-292 detected lung type I alveolar epithelial cells, lymphatic endothelial cells, and glomerular/Bowman's capsule in the kidney using immunohistochemistry. Hence, these results propose the usefulness of PMab-292 in analyzing ferret-derived tissues for SARS-CoV-2 research.
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Affiliation(s)
- Nohara Goto
- Department of Molecular Pharmacology, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Hiroyuki Suzuki
- Department of Molecular Pharmacology, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Tomohiro Tanaka
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Teizo Asano
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Mika K Kaneko
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Yukinari Kato
- Department of Molecular Pharmacology, Tohoku University Graduate School of Medicine, Sendai, Japan.,Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Japan
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4
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Suzuki H, Kaneko MK, Kato Y. Roles of Podoplanin in Malignant Progression of Tumor. Cells 2022; 11:cells11030575. [PMID: 35159384 PMCID: PMC8834262 DOI: 10.3390/cells11030575] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Revised: 02/02/2022] [Accepted: 02/05/2022] [Indexed: 02/07/2023] Open
Abstract
Podoplanin (PDPN) is a cell-surface mucin-like glycoprotein that plays a critical role in tumor development and normal development of the lung, kidney, and lymphatic vascular systems. PDPN is overexpressed in several tumors and is involved in their malignancy. PDPN induces platelet aggregation through binding to platelet receptor C-type lectin-like receptor 2. Furthermore, PDPN modulates signal transductions that regulate cell proliferation, differentiation, migration, invasion, epithelial-to-mesenchymal transition, and stemness, all of which are crucial for the malignant progression of tumor. In the tumor microenvironment (TME), PDPN expression is upregulated in the tumor stroma, including cancer-associated fibroblasts (CAFs) and immune cells. CAFs play significant roles in the extracellular matrix remodeling and the development of immunosuppressive TME. Additionally, PDPN functions as a co-inhibitory molecule on T cells, indicating its involvement with immune evasion. In this review, we describe the mechanistic basis and diverse roles of PDPN in the malignant progression of tumors and discuss the possibility of the clinical application of PDPN-targeted cancer therapy, including cancer-specific monoclonal antibodies, and chimeric antigen receptor T technologies.
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Affiliation(s)
- Hiroyuki Suzuki
- Department of Molecular Pharmacology, Tohoku University Graduate School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai 980-8575, Japan
- Correspondence: (H.S.); (Y.K.); Tel.: +81-22-717-8207 (H.S. & Y.K.)
| | - Mika K. Kaneko
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai 980-8575, Japan;
| | - Yukinari Kato
- Department of Molecular Pharmacology, Tohoku University Graduate School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai 980-8575, Japan
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai 980-8575, Japan;
- Correspondence: (H.S.); (Y.K.); Tel.: +81-22-717-8207 (H.S. & Y.K.)
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Tanaka T, Asano T, Sano M, Takei J, Hosono H, Nanamiya R, Tateyama N, Kaneko MK, Kato Y. Epitope Mapping of the Anti-California Sea Lion Podoplanin Monoclonal Antibody PMab-269 Using Alanine-Scanning Mutagenesis and ELISA. Monoclon Antib Immunodiagn Immunother 2021; 40:196-200. [PMID: 34283661 DOI: 10.1089/mab.2021.0017] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Podoplanin (PDPN) plays a pivotal role in platelet aggregation, embryo development, and tumor progression. PDPN is universally expressed in many mammalian species, and is considered a typical lymphatic endothelial cell marker. We have previously developed the mouse anti-California sea lion (Zalophus californianus) PDPN (seaPDPN) monoclonal antibody (mAb), clone PMab-269, which is suitable for different experimental applications, including flow cytometry, Western blotting, and immunohistochemistry. In this study, we identified the PMab-269 epitope of the seaPDPN by enzyme-linked immunosorbent assay using deletion mutants and point mutants generated for seaPDPN. Our results demonstrated that PMab-269 recognized the peptide, corresponding to the amino acids 63-82 of seaPDPN. Furthermore, the reactions of PMab-269 to seven alanine-substituted peptides, such as P68A, D76A, F77A, H78A, L79A, E80A, and D81A, were abolished among 20 alanine-substituted peptides. We identified the seven amino acids (Pro68, Asp76, Phe77, His78, Leu79, Glu80, and Asp81) as the critical epitope targeted by PMab-269. The successful identification of the PMab-269 epitope might contribute to the pathophysiological investigations of seaPDPN.
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Affiliation(s)
- Tomohiro Tanaka
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Teizo Asano
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Masato Sano
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Junko Takei
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Hideki Hosono
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Ren Nanamiya
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Nami Tateyama
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Mika K Kaneko
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Yukinari Kato
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Japan.,Department of Molecular Pharmacology, Tohoku University Graduate School of Medicine, Sendai, Japan
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6
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Kaneko MK, Sano M, Takei J, Asano T, Sayama Y, Hosono H, Kobayashi A, Konnai S, Kato Y. Development and Characterization of Anti-Sheep Podoplanin Monoclonal Antibodies PMab-253 and PMab-260. Monoclon Antib Immunodiagn Immunother 2020; 39:144-155. [PMID: 32679010 DOI: 10.1089/mab.2020.0018] [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] [Indexed: 01/05/2023] Open
Abstract
Anti-podoplanin (PDPN) monoclonal antibodies (mAbs) are needed as markers for lymphatic endothelial cells or type I alveolar cells in immunohistochemical analyses. We have developed anti-PDPN mAbs for many species, including humans, mice, rats, rabbits, dogs, cats, bovines, pigs, Tasmanian devils, alpacas, tigers, whales, goats, horses, and bears. This study develops and characterizes anti-sheep PDPN (sPDPN) mAbs using Cell-Based Immunization and Screening (CBIS) method. A RAP14 tag was added to the N-terminus of sPDPN, and an anti-RAP14 tag mAb (PMab-2) was used to measure the expression level of sPDPN in flow cytometry and Western blots. We immunized mice with sPDPN-overexpressing Chinese hamster ovary (CHO)-K1 (CHO/sPDPN) cells and screened mAbs against sPDPN using flow cytometry. Two of the mAbs, PMab-253 (immunoglobulin M [IgM], kappa) and PMab-260 (IgM, kappa), detected CHO/sPDPN cells specifically using flow cytometry and Western blots. Both PMab-253 and PMab-260 stained the renal glomerulus and Bowman's capsule, lymphatic endothelial cells of the lung and colon, and type I alveolar cells of the lung, suggesting PMab-253 and PMab-260, which were developed by CBIS method, can be applied to functional analyses of sPDPN. We also determined the binding epitope of PMab-253 and PMab-260 using flow cytometry. Analysis of sPDPN deletion mutants revealed that the N-terminus of the PMab-253 and PMab-260 epitope exists between amino acids 110 and 115 of sPDPN. Analysis of sPDPN point mutations revealed that the critical epitope of PMab-253 and PMab-260 includes Thr112 and Ser113 of sPDPN, indicating that the PMab-253 and PMab-260 epitope are independent of the platelet aggregation-stimulating (PLAG) domain or the PLAG-like domain of sPDPN.
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Affiliation(s)
- Mika K Kaneko
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Masato Sano
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Junko Takei
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Teizo Asano
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Yusuke Sayama
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Hideki Hosono
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Atsushi Kobayashi
- Laboratory of Comparative Pathology, Faculty of Veterinary Medicine, Hokkaido University, Sapporo, Japan
| | - Satoru Konnai
- Laboratory of Infectious Diseases, Department of Disease Control, Faculty of Veterinary Medicine, Hokkaido University, Sapporo, Japan.,Department of Advanced Pharmaceutics, Faculty of Veterinary Medicine, Hokkaido University, Sapporo, Japan
| | - Yukinari Kato
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Japan.,New Industry Creation Hatchery Center, Tohoku University, Sendai, Japan
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7
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Kato Y, Furusawa Y, Sano M, Takei J, Nakamura T, Yanaka M, Okamoto S, Handa S, Komatsu Y, Asano T, Sayama Y, Kaneko MK. Development of an Anti-Sheep Podoplanin Monoclonal Antibody PMab-256 for Immunohistochemical Analysis of Lymphatic Endothelial Cells. Monoclon Antib Immunodiagn Immunother 2020; 39:82-90. [DOI: 10.1089/mab.2020.0005] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Affiliation(s)
- Yukinari Kato
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Japan
- New Industry Creation Hatchery Center, Tohoku University, Sendai, Japan
| | - Yoshikazu Furusawa
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Masato Sano
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Junko Takei
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Takuro Nakamura
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Miyuki Yanaka
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Saki Okamoto
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Saori Handa
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Yu Komatsu
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Teizo Asano
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Yusuke Sayama
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Mika K. Kaneko
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Japan
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Kato Y, Sano M, Asano T, Sayama Y, Kaneko MK. Thr80 of Sheep Podoplanin Is a Critical Epitope of the Antisheep Podoplanin Monoclonal Antibody: PMab-256. Monoclon Antib Immunodiagn Immunother 2020; 39:95-100. [PMID: 32423295 DOI: 10.1089/mab.2020.0010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
An antisheep podoplanin (sPDPN) monoclonal antibody (mAb), PMab-256, has recently been established. PMab-256 shows positive immunostaining for lymphatic endothelial cells, lung type I alveolar cells, and kidney podocytes. PDPN possesses three platelet-aggregation-stimulating (PLAG) domains, PLAG1, PLAG2, and PLAG3, and a PLAG-like domain (PLD). The binding epitope of many anti-PDPN mAbs is located in PLAG domains or PLD. The purpose of this study is to determine the binding epitope of PMab-256. Analysis of sPDPN deletion mutants revealed that the N-terminus of the PMab-256 epitope exists between amino acids 75 and 80 of sPDPN. Furthermore, analysis of sPDPN point mutations demonstrated that the critical epitope includes Thr80 of sPDPN, indicating that the PMab-256 epitope is in the PLD of sPDPN.
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Affiliation(s)
- Yukinari Kato
- Department of Antibody Drug Development, Graduate School of Medicine, Tohoku University, Sendai, Japan.,New Industry Creation Hatchery Center, Tohoku University, Sendai, Japan
| | - Masato Sano
- Department of Antibody Drug Development, Graduate School of Medicine, Tohoku University, Sendai, Japan
| | - Teizo Asano
- Department of Antibody Drug Development, Graduate School of Medicine, Tohoku University, Sendai, Japan
| | - Yusuke Sayama
- Department of Antibody Drug Development, Graduate School of Medicine, Tohoku University, Sendai, Japan
| | - Mika K Kaneko
- Department of Antibody Drug Development, Graduate School of Medicine, Tohoku University, Sendai, Japan
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Sayama Y, Sano M, Asano T, Furusawa Y, Takei J, Nakamura T, Yanaka M, Okamoto S, Handa S, Komatsu Y, Nakamura Y, Yanagawa M, Kaneko MK, Kato Y. Epitope Mapping of PMab-241, a Lymphatic Endothelial Cell-Specific Anti-Bear Podoplanin Monoclonal Antibody. Monoclon Antib Immunodiagn Immunother 2020; 39:77-81. [PMID: 32240034 DOI: 10.1089/mab.2020.0004] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Anti-bear podoplanin (bPDPN) monoclonal antibodies (mAbs), including PMab-247 and PMab-241, have been previously established. Although PMab-247 has shown positive immunostaining for lymphatic endothelial cells (LECs), type I alveolar cells of the lung, and podocytes of the kidney, PMab-241 stains LECs but does not react with lung type I alveolar cells. PDPN possesses three platelet aggregation-stimulating (PLAG) domains (PLAG1, PLAG2, and PLAG3) and the PLAG-like domain (PLD). The binding epitope of PMab-247 was previously determined to include bPDPN residues Asp76, Arg78, Glu80, and Arg82. Among these, Glu80 and Arg82 are included in PLD of bPDPN. The purpose of this study is to determine the binding epitope of PMab-241 and to clarify the difference between these two anti-bPDPN mAbs. Analysis of bPDPN deletion mutants revealed that the N-terminus of the PMab-241 epitope exists between amino acids (aa) 75 and 80 of bPDPN. In addition, analysis of bPDPN point mutants demonstrated that the critical epitope of PMab-241 includes Thr75, Asp76, and Arg78 of bPDPN. The binding epitopes of PMab-241 and PMab-247 seem to overlap, but this slight difference may be sufficient to provide the specificity of PMab-241 to discriminate LECs from type I alveolar cells of the lung.
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Affiliation(s)
- Yusuke Sayama
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Masato Sano
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Teizo Asano
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Yoshikazu Furusawa
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Junko Takei
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Takuro Nakamura
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Miyuki Yanaka
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Saki Okamoto
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Saori Handa
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Yu Komatsu
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Yoshimi Nakamura
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Mikiko Yanagawa
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Mika K Kaneko
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Yukinari Kato
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Japan
- New Industry Creation Hatchery Center, Tohoku University, Sendai, Japan
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