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Hiyoshi H, Sakuma K, Asano S, Napier SC, Konagaya S, Mochida T, Ueno H, Watanabe T, Kassai Y, Matsumoto H, Ito R, Toyoda T. Identification and removal of unexpected proliferative off-target cells emerging after iPSC-derived pancreatic islet cell implantation. Proc Natl Acad Sci U S A 2024; 121:e2320883121. [PMID: 38598342 PMCID: PMC11032438 DOI: 10.1073/pnas.2320883121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2023] [Accepted: 03/12/2024] [Indexed: 04/12/2024] Open
Abstract
Differentiation of pancreatic endocrine cells from human pluripotent stem cells (PSCs) has been thoroughly investigated for application in cell therapy against diabetes. In the context of induced pancreatic endocrine cell implantation, previous studies have reported graft enlargement resulting from off-target pancreatic lineage cells. However, there is currently no documented evidence of proliferative off-target cells beyond the pancreatic lineage in existing studies. Here, we show that the implantation of seven-stage induced PSC-derived pancreatic islet cells (s7-iPICs) leads to the emergence of unexpected off-target cells with proliferative capacity via in vivo maturation. These cells display characteristics of both mesenchymal stem cells (MSCs) and smooth muscle cells (SMCs), termed proliferative MSC- and SMC-like cells (PMSCs). The frequency of PMSC emergence was found to be high when 108 s7-iPICs were used. Given that clinical applications involve the use of a greater number of induced cells than 108, it is challenging to ensure the safety of clinical applications unless PMSCs are adequately addressed. Accordingly, we developed a detection system and removal methods for PMSCs. To detect PMSCs without implantation, we implemented a 4-wk-extended culture system and demonstrated that putative PMSCs could be reduced by compound treatment, particularly with the taxane docetaxel. When docetaxel-treated s7-iPICs were implanted, the PMSCs were no longer observed. This study provides useful insights into the identification and resolution of safety issues, which are particularly important in the field of cell-based medicine using PSCs.
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Affiliation(s)
- Hideyuki Hiyoshi
- Takeda-CiRA Discovery and Innovation, Takeda Pharmaceutical Company Limited, Fujisawa, Kanagawa251-8555, Japan
- Takeda-CiRA Joint Program for iPS Cell Applications, Fujisawa, Kanagawa251-8555, Japan
| | - Kensuke Sakuma
- Takeda-CiRA Discovery and Innovation, Takeda Pharmaceutical Company Limited, Fujisawa, Kanagawa251-8555, Japan
- Takeda-CiRA Joint Program for iPS Cell Applications, Fujisawa, Kanagawa251-8555, Japan
| | - Shinya Asano
- Axcelead Drug Discovery Partners, Inc., Fujisawa, Kanagawa251-8555, Japan
| | - Stephanie C. Napier
- Takeda-CiRA Discovery and Innovation, Takeda Pharmaceutical Company Limited, Fujisawa, Kanagawa251-8555, Japan
- Takeda-CiRA Joint Program for iPS Cell Applications, Fujisawa, Kanagawa251-8555, Japan
| | - Shuhei Konagaya
- Takeda-CiRA Joint Program for iPS Cell Applications, Fujisawa, Kanagawa251-8555, Japan
- Department of Cell Growth and Differentiation, Center for iPS Cell Research and Application, Kyoto University, Kyoto606-8397, Japan
| | - Taisuke Mochida
- Takeda-CiRA Discovery and Innovation, Takeda Pharmaceutical Company Limited, Fujisawa, Kanagawa251-8555, Japan
- Takeda-CiRA Joint Program for iPS Cell Applications, Fujisawa, Kanagawa251-8555, Japan
| | - Hikaru Ueno
- Takeda-CiRA Discovery and Innovation, Takeda Pharmaceutical Company Limited, Fujisawa, Kanagawa251-8555, Japan
- Takeda-CiRA Joint Program for iPS Cell Applications, Fujisawa, Kanagawa251-8555, Japan
| | - Takeshi Watanabe
- Drug Safety Research and Evaluation, Takeda Pharmaceutical Company Limited, Fujisawa, Kanagawa251-8555, Japan
| | - Yoshiaki Kassai
- Takeda-CiRA Discovery and Innovation, Takeda Pharmaceutical Company Limited, Fujisawa, Kanagawa251-8555, Japan
- Takeda-CiRA Joint Program for iPS Cell Applications, Fujisawa, Kanagawa251-8555, Japan
| | - Hirokazu Matsumoto
- Takeda-CiRA Discovery and Innovation, Takeda Pharmaceutical Company Limited, Fujisawa, Kanagawa251-8555, Japan
- Takeda-CiRA Joint Program for iPS Cell Applications, Fujisawa, Kanagawa251-8555, Japan
| | - Ryo Ito
- Takeda-CiRA Discovery and Innovation, Takeda Pharmaceutical Company Limited, Fujisawa, Kanagawa251-8555, Japan
- Takeda-CiRA Joint Program for iPS Cell Applications, Fujisawa, Kanagawa251-8555, Japan
| | - Taro Toyoda
- Takeda-CiRA Joint Program for iPS Cell Applications, Fujisawa, Kanagawa251-8555, Japan
- Department of Cell Growth and Differentiation, Center for iPS Cell Research and Application, Kyoto University, Kyoto606-8397, Japan
- Department of Life Science Frontiers, Center for iPS Cell Research and Application, Kyoto University, Kyoto606-8397, Japan
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Hiyoshi H, Sakuma K, Tsubooka-Yamazoe N, Asano S, Mochida T, Yamaura J, Konagaya S, Fujii R, Matsumoto H, Ito R, Toyoda T. Characterization and reduction of non-endocrine cells accompanying islet-like endocrine cells differentiated from human iPSC. Sci Rep 2022; 12:4740. [PMID: 35304548 PMCID: PMC8933508 DOI: 10.1038/s41598-022-08753-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Accepted: 03/11/2022] [Indexed: 11/09/2022] Open
Abstract
The differentiation of pancreatic endocrine cells from human pluripotent stem cells has been thoroughly investigated for their application in cell therapy against diabetes. Although non-endocrine cells are inevitable contaminating by-products of the differentiation process, a comprehensive profile of such cells is lacking. Therefore, we characterized non-endocrine cells in iPSC-derived pancreatic islet cells (iPIC) using single-cell transcriptomic analysis. We found that non-endocrine cells consist of (1) heterogeneous proliferating cells, and (2) cells with not only pancreatic traits but also liver or intestinal traits marked by FGB or AGR2. Non-endocrine cells specifically expressed FGFR2, PLK1, and LDHB. We demonstrated that inhibition of pathways involving these genes selectively reduced the number of non-endocrine cells in the differentiation process. These findings provide useful insights into cell purification approaches and contribute to the improvement of the mass production of endocrine cells for stem cell-derived cell therapy for diabetes.
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Affiliation(s)
- Hideyuki Hiyoshi
- T-CiRA Discovery, Research, Takeda Pharmaceutical Company Limited, 26-1, Muraoka-Higashi 2-chome, Fujisawa, Kanagawa, 251-8555, Japan. .,Takeda-CiRA Joint Program for iPS Cell Applications (T-CiRA), Fujisawa, Kanagawa, Japan.
| | - Kensuke Sakuma
- T-CiRA Discovery, Research, Takeda Pharmaceutical Company Limited, 26-1, Muraoka-Higashi 2-chome, Fujisawa, Kanagawa, 251-8555, Japan.,Takeda-CiRA Joint Program for iPS Cell Applications (T-CiRA), Fujisawa, Kanagawa, Japan.,Orizuru Therapeutics, Inc, Fujisawa, Kanagawa, Japan
| | - Noriko Tsubooka-Yamazoe
- T-CiRA Discovery, Research, Takeda Pharmaceutical Company Limited, 26-1, Muraoka-Higashi 2-chome, Fujisawa, Kanagawa, 251-8555, Japan.,Takeda-CiRA Joint Program for iPS Cell Applications (T-CiRA), Fujisawa, Kanagawa, Japan.,Orizuru Therapeutics, Inc, Fujisawa, Kanagawa, Japan
| | - Shinya Asano
- Axcelead Drug Discovery Partners, Inc, Fujisawa, Kanagawa, Japan
| | - Taisuke Mochida
- T-CiRA Discovery, Research, Takeda Pharmaceutical Company Limited, 26-1, Muraoka-Higashi 2-chome, Fujisawa, Kanagawa, 251-8555, Japan.,Takeda-CiRA Joint Program for iPS Cell Applications (T-CiRA), Fujisawa, Kanagawa, Japan
| | - Junji Yamaura
- Takeda-CiRA Joint Program for iPS Cell Applications (T-CiRA), Fujisawa, Kanagawa, Japan.,Pharmaceutical Science, Takeda Pharmaceutical Company Limited, Fujisawa, Kanagawa, Japan
| | - Shuhei Konagaya
- Department of Cell Growth and Differentiation, Center for iPS Cell Research and Application (CiRA), Kyoto University, 53 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto, 606-8507, Japan.,Takeda-CiRA Joint Program for iPS Cell Applications (T-CiRA), Fujisawa, Kanagawa, Japan.,Orizuru Therapeutics, Inc, Fujisawa, Kanagawa, Japan
| | - Ryo Fujii
- Axcelead Drug Discovery Partners, Inc, Fujisawa, Kanagawa, Japan
| | - Hirokazu Matsumoto
- T-CiRA Discovery, Research, Takeda Pharmaceutical Company Limited, 26-1, Muraoka-Higashi 2-chome, Fujisawa, Kanagawa, 251-8555, Japan.,Takeda-CiRA Joint Program for iPS Cell Applications (T-CiRA), Fujisawa, Kanagawa, Japan
| | - Ryo Ito
- T-CiRA Discovery, Research, Takeda Pharmaceutical Company Limited, 26-1, Muraoka-Higashi 2-chome, Fujisawa, Kanagawa, 251-8555, Japan.,Takeda-CiRA Joint Program for iPS Cell Applications (T-CiRA), Fujisawa, Kanagawa, Japan.,Orizuru Therapeutics, Inc, Fujisawa, Kanagawa, Japan
| | - Taro Toyoda
- Department of Cell Growth and Differentiation, Center for iPS Cell Research and Application (CiRA), Kyoto University, 53 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto, 606-8507, Japan. .,Takeda-CiRA Joint Program for iPS Cell Applications (T-CiRA), Fujisawa, Kanagawa, Japan.
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Konagaya S, Iwata H. Chemically defined conditions for long-term maintenance of pancreatic progenitors derived from human induced pluripotent stem cells. Sci Rep 2019; 9:640. [PMID: 30679498 PMCID: PMC6345937 DOI: 10.1038/s41598-018-36606-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2017] [Accepted: 11/23/2018] [Indexed: 12/21/2022] Open
Abstract
Large numbers of hormone-releasing cells, approximately 109 endocrine cells, are required to treat type I diabetes patients by cell transplantation. The SOX9-positive pancreatic epithelium proliferates extensively during the early stages of pancreatic development. SOX9-positive pancreatic epithelium is thought to be an expandable cell source of β cells for transplantation therapy. In this study, we attempted to expand pancreatic progenitors (PPs: PDX1+/SOX9+) derived from four human iPSC lines in three-dimensional (3D) culture using a chemically defined medium and examined the potential of the derived PPs to differentiate into β-like cells. PPs from four human iPSC lines were maintained and effectively proliferated in a chemically defined medium containing epidermal growth factor and R-spondin-1, CHIR99021, fibroblast growth factor-7, and SB431542. PPs derived from one iPSC line can be expanded by more than 104-fold in chemically defined medium containing two of the fives, epidermal growth factor and R-spondin-1. The expanded PPs were also stable following cryopreservation. After freezing and thawing, the PPs proliferated without a decrease in the rate. PPs obtained after 50 days of culture successfully differentiated into insulin-positive β-like cells, glucagon-positive α-like cells, and somatostatin-positive δ-like cells. The differentiation efficiency of expanded PPs was similar to that of PPs without expansion culture.
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Affiliation(s)
- Shuhei Konagaya
- Institute for Frontier Medical and Life Sciences, Kyoto University, 53 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto, 606-8507, Japan
| | - Hiroo Iwata
- Institute for Frontier Medical and Life Sciences, Kyoto University, 53 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto, 606-8507, Japan. .,Research Promotion Institution for COI Site, Kyoto University, Yoshida-honmachi, Sakyo-ku, Kyoto, 606-8501, Japan. .,The "Compass to Healthy Life" Research Complex Program, RIKEN, 6-7-1 Minatojima-Minamimachi, Chuo-ku, Kobe, 650-0047, Japan.
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Hirano K, Konagaya S, Turner A, Noda Y, Kitamura S, Kotera H, Iwata H. Closed-channel culture system for efficient and reproducible differentiation of human pluripotent stem cells into islet cells. Biochem Biophys Res Commun 2017; 487:344-350. [DOI: 10.1016/j.bbrc.2017.04.062] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2017] [Accepted: 04/12/2017] [Indexed: 10/19/2022]
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Komura T, Kato K, Konagaya S, Nakaji-Hirabayashi T, Iwata H. Optimization of surface-immobilized extracellular matrices for the proliferation of neural progenitor cells derived from induced pluripotent stem cells. Biotechnol Bioeng 2015; 112:2388-96. [DOI: 10.1002/bit.25636] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2014] [Revised: 04/17/2015] [Accepted: 04/27/2015] [Indexed: 12/15/2022]
Affiliation(s)
- Takashi Komura
- Institute for Frontier Medical Sciences; Kyoto University; 53 Kawahara-cho, Shogoin, Sakyo-ku Kyoto 606-8507 Japan
| | - Koichi Kato
- Institute for Frontier Medical Sciences; Kyoto University; 53 Kawahara-cho, Shogoin, Sakyo-ku Kyoto 606-8507 Japan
| | - Shuhei Konagaya
- Institute for Frontier Medical Sciences; Kyoto University; 53 Kawahara-cho, Shogoin, Sakyo-ku Kyoto 606-8507 Japan
| | - Tadashi Nakaji-Hirabayashi
- Institute for Frontier Medical Sciences; Kyoto University; 53 Kawahara-cho, Shogoin, Sakyo-ku Kyoto 606-8507 Japan
| | - Hiroo Iwata
- Institute for Frontier Medical Sciences; Kyoto University; 53 Kawahara-cho, Shogoin, Sakyo-ku Kyoto 606-8507 Japan
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Komatsu M, Konagaya S, Egawa EY, Iwata H. Maturation of human iPS cell-derived dopamine neuron precursors in alginate-Ca(2+) hydrogel. Biochim Biophys Acta Gen Subj 2015; 1850:1669-75. [PMID: 25952075 DOI: 10.1016/j.bbagen.2015.04.011] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2014] [Revised: 04/14/2015] [Accepted: 04/27/2015] [Indexed: 01/25/2023]
Abstract
BACKGROUND Pluripotent stem cells (embryonic stem/induced pluripotent stem cells) have been widely studied as a potential cell source for cell transplantation therapy of Parkinson's disease. However, some difficulties remain to be overcome. These include the need to prepare a large number of dopamine (DA) neurons for clinical use and to culture the cells for a long period to allow their functional maturation and the removal of undifferentiated cells. METHODS In this study, aggregates of DA neuron precursors were enclosed in alginate-Ca(2+) microbeads, and the encapsulated aggregates were cultured for 25days to induce cell maturation. RESULTS More than 60% of cells in the aggregates differentiated into tyrosine hydroxylase-positive DA neurons. The aggregates could release DA at the same level as aggregates maintained on culture dishes without encapsulation. In addition, by exposure to a citrate solution, the alginate-Ca(2+) gel layer could be easily removed from aggregates without damaging the DA neurons. When the aggregates were transplanted into rat brain, viable cells were found in the graft at one week post-transplantation, with cells extending neurites into the host tissue. CONCLUSIONS Cell aggregates encapsulated in alginate-Ca(2+) beads successfully differentiated into mature DA neurons. GENERAL SIGNIFICANCE The alginate-Ca(2+) microbead is suitable for maintaining DA precursor aggregates for a long period to allow their functional maturation.
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Affiliation(s)
- Mitsue Komatsu
- Institute for Frontier Medical Sciences, Kyoto University, 53 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507, Japan
| | - Shuhei Konagaya
- Institute for Frontier Medical Sciences, Kyoto University, 53 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507, Japan
| | - Edgar Y Egawa
- Institute for Frontier Medical Sciences, Kyoto University, 53 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507, Japan
| | - Hiroo Iwata
- Institute for Frontier Medical Sciences, Kyoto University, 53 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507, Japan.
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Konagaya S, Iwata H. Microencapsulation of dopamine neurons derived from human induced pluripotent stem cells. Biochim Biophys Acta Gen Subj 2014; 1850:22-32. [PMID: 25281770 DOI: 10.1016/j.bbagen.2014.09.025] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2014] [Revised: 09/10/2014] [Accepted: 09/24/2014] [Indexed: 10/24/2022]
Abstract
BACKGROUND Dopamine neurons derived from induced pluripotent stem cells have been widely studied for the treatment of Parkinson's disease. However, various difficulties remain to be overcome, such as tumor formation, fragility of dopamine neurons, difficulty in handling large numbers of dopamine neurons, and immune reactions. In this study, human induced pluripotent stem cell-derived precursors of dopamine neurons were encapsulated in agarose microbeads. Dopamine neurons in microbeads could be handled without specific protocols, because the microbeads protected the fragile dopamine neurons from mechanical stress. METHODS hiPS cells were seeded on a Matrigel-coated dish and cultured to induce differentiation into a dopamine neuronal linage. On day 18 of culture, cells were collected from the culture dishes and seeded into U-bottom 96-well plates to induce cell aggregate formation. After 5 days, cell aggregates were collected from the plates and microencapsulated in agarose microbeads. The microencapsulated aggregates were cultured for an additional 45 days to induce maturation of dopamine neurons. RESULTS Approximately 60% of all cells differentiated into tyrosine hydroxylase-positive neurons in agarose microbeads. The cells released dopamine for more than 40 days. In addition, microbeads containing cells could be cryopreserved. CONCLUSION hiPS cells were successfully differentiated into dopamine neurons in agarose microbeads. GENERAL SIGNIFICANCE Agarose microencapsulation provides a good supporting environment for the preparation and storage of dopamine neurons.
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Affiliation(s)
- Shuhei Konagaya
- Institute for Frontier Medical Sciences, Kyoto University, 53 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507, Japan
| | - Hiroo Iwata
- Institute for Frontier Medical Sciences, Kyoto University, 53 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507, Japan.
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Konagaya S, Kato K, Nakaji-Hirabayashi T, Iwata H. Selective and rapid expansion of human neural progenitor cells on substrates with terminally anchored growth factors. Biomaterials 2013; 34:6008-14. [DOI: 10.1016/j.biomaterials.2013.04.041] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2013] [Accepted: 04/23/2013] [Indexed: 12/12/2022]
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Konagaya S, Kato K, Nakaji-Hirabayashi T, Arima Y, Iwata H. Array-based functional screening of growth factors toward optimizing neural stem cell microenvironments. Biomaterials 2011; 32:5015-22. [DOI: 10.1016/j.biomaterials.2011.03.066] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2011] [Accepted: 03/28/2011] [Indexed: 01/28/2023]
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Abstract
A salmon cystatin cDNA clone was isolated from a chum salmon cDNA library. The clone encoded a full-length extracellular-type cystatin and its signal peptide and included 5'- and 3'-untranslated regions. The deduced amino acid sequence showed a high degree of sequence similarity to mammalian cystatin C, chicken egg cystatin, and chum salmon pituitary cystatin. By Northern blot analysis, the salmon cystatin was found to show apparently non-tissue specific expression. Because platyfish EHS cells transfected with a cystatin expression vector produced a 13 kDa mature cystatin in the culture medium, the salmon cystatin was considered to act as an extracellular type of cystatin in the fish cells. These findings indicate that the salmon cystatin is a homolog of mammalian cystatin C.
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Affiliation(s)
- M Yamashita
- National Research Institute of Fisheries Science, Yokohama.
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Yamashita M, Konagaya S. A novel cysteine protease inhibitor of the egg of chum salmon, containing a cysteine-rich thyroglobulin-like motif. J Biol Chem 1996; 271:1282-4. [PMID: 8576113 DOI: 10.1074/jbc.271.3.1282] [Citation(s) in RCA: 54] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
ECI, one of three isoforms of cysteine protease inhibitor found in chum salmon eggs was purified to homogeneity, and its complete amino acid sequence was determined. The primary structure of ECI did not resemble those of other cysteine protease inhibitors of the cystatin superfamily but did resemble that of a cysteine-rich motif found as a repetitive structural element in thyroglobulin and several other proteins. The function of the cysteine-rich motif is not yet hypothesis. Two cysteine motif proteins, thyroglobulin and entactin, were tested for papain inhibitory activity and found to have none.
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Affiliation(s)
- M Yamashita
- National Research Institute of Fisheries Science, Yokohama, Japan
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Abstract
Two different cysteine protease inhibitors (Forms I and II) were isolated from chum salmon egg, and their molecular weights were found to be 16,000 and 11,000, respectively. When the N-terminal amino acid sequences of Forms I and II were compared, 67% of the residues were identical but no apparent homology was found between these inhibitors and cystatins of higher vertebrates. Because the amounts of half-cystine were estimated to be 7-8 residues per molecule, they can be classified into a new group of the cystatin superfamily.
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Affiliation(s)
- M Yamashita
- National Research Institute of Fisheries Science, Tokyo
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Yamashita M, Konagaya S. High activities of cathepsins B, D, H, and L in the white muscle of chum salmon in spawning migration. Comp Biochem Physiol B 1990; 95:149-52. [PMID: 2331869 DOI: 10.1016/0305-0491(90)90262-r] [Citation(s) in RCA: 30] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
1. Activities of cathepsins, lysosomal hydrolytic enzymes and cysteine protease inhibitor in both the white and red muscles of chum salmon (Oncorhynchus keta) caught during spawning and feeding migrations were compared. 2. In the white muscle, cathepsins B, D, H and L activities were 3-7 times higher in the fish in spawning migration than those in feeding migration. However, in the red muscle, no such marked differences were observed between them. 3. Cysteine protease inhibitory activity and extractable protein content in the white muscle of the fish in spawning migration were about 40% lower than those in feeding migration. 4. The present study supports the conception that the cathepsins are related to protein catabolism of the fish during spawning migration.
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Affiliation(s)
- M Yamashita
- National Research Institute of Fisheries Science, Ministry of Agriculture, Forestry and Fisheries of Japan, Tokyo
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Yamashita M, Konagaya S. Purification and characterization of cathepsin L from the white muscle of chum salmon, Oncorhynchus keta. Comp Biochem Physiol B 1990; 96:247-52. [PMID: 2361361 DOI: 10.1016/0305-0491(90)90371-y] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
1. Cathepsin L of the white muscle of chum salmon (Oncorhynchus keta) in spawning migration was purified to homogeneity by a series of chromatography on DEAE-Sephadex (1st), SP-Sephadex, CM-Sephadex, DEAE-Sephadex (2nd) and Sephadex G-100. 2. The molecular weight of salmon muscle cathepsin L was estimated to be 30,000 and its isoelectric point was 5.2. 3. Cathepsin L had a pH optimum of 5.6, required a thiol-reducing reagent for activation, and was inhibited by cysteine protease inhibitors. 4. The Km and kcat values for Z-Phe-Arg-MCA were determined to be 1.68 microM and 15.8 s-1, respectively. This enzyme hydrolyzed proteins such as insulin B chain, hemoglobin, serum albumin and azocasein easily. 5. The bond specificity to oxidized insulin B chain inferred that the enzyme had a preference for hydrophobic amino acid in P2 and P3 residues.
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Affiliation(s)
- M Yamashita
- National Research Institute of Fisheries Science, Tokoyo, Japan
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