The Experts below are selected from a list of 297 Experts worldwide ranked by ideXlab platform
Marina V. Backer - One of the best experts on this subject based on the ideXlab platform.
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Adapter protein for site-specific conjugation of Payloads for targeted drug delivery.
Bioconjugate chemistry, 2004Co-Authors: Marina V. Backer, Timur I. Gaynutdinov, Vimal Patel, Brian T. Jehning, Eugene Myshkin, Joseph M. BackerAbstract:High-affinity interactions of two fragments of human RNase I (1−15-aa Hu-tag and 21−125-aa HuS adapter protein) can be used for assembly of targeting drug delivery complexes. In this approach, a targeting protein is expressed as a fusion protein with a 15-aa Hu-tag, while HuS is conjugated to a drug (or a drug carrier) creating a “Payload” Module, which is then bound noncovalently to the Hu-tag of the targeting protein. Although this approach eliminates chemical modifications of targeting proteins, the Payload Modules are still constructed by random cross-linking of drugs or drug carriers to an adapter protein that might lead to functional heterogeneity of the complexes. To avoid this problem, we engineered an adapter protein HuS(N88C) with an unpaired cysteine in position 88 that can be directly modified without interference with activity of assembled targeting complexes. HuS(N88C) binds Hu-tagged annexin V with KD of 50 ± 6 nM, which is comparable to that of wild-type HuS. To demonstrate the utility of ...
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imaging angiogenesis in early stages of breast cancer using a standardized radiolabeled adapter protein docked to vascular endothelial growth factor
Breast Cancer Research, 2003Co-Authors: Stefanie Mandl, Marina V. Backer, Timur I. Gaynutdinov, Joseph M. Backer, Francis G Blankenberg, Caitlin E Oconnellrodwell, Carina Mari, Jl Vanderheyden, Christopher H ContagAbstract:Tumor growth, local invasion, and metastatic dissemination are dependent on the formation of new microvessels. Angiogenesis is therefore a crucial event in tumor progression. In recent years anti-angiogenic agents have been developed as a novel approach to cancer treatment. Successful intervention with tumor angiogenesis can induce tumor vasculature regression, leading to a complete cessation of tumor growth. Clinically, however, anti-angiogenesis inhibitors have been used with marginal success. For the development of novel effective anti-angiogenic therapies it is of crucial interest, therefore, to be able to screen new treatments for both the effects on the tumor vasculature as well as the tumor burden itself. We have engineered the murine breast cancer cell line 4T1 to stably express the luciferase gene of the North American firefly. This allowed us to visualize tumor burden by in vivo bioluminescence imaging. The 4T1 mouse mammary carcinoma is derived from Balb/c mice and very closely models advanced stage (stage IV) human breast cancer in immunogenicity, metastatic properties and growth characteristics. Additionally, we have developed the adapter/docking tag system based on interactions between an 18–127 amino acid fragment of human RNase I and a 1–15 amino acid fragment of RNase I fused to a targeting protein. To visualize angiogenesis we applied to the docking system labeling vascular endothelial growth factor with 99mTc in 4T1 breast cancer tumor-bearing mice. In preliminary studies we were able to detect neovascularization in mouse breast cancer tumor nodules as small as 2–3 mm in diameter. We found that the 99mTc-labeled vascular endothelial growth factor complexes selectively and specifically bound to tumor neovasculature. We expect that 99mTc-Adapter, a broadly applicable and general humanized radionuclide imaging 'Payload' Module, can be readily employed for a non-destructive labeling of many targeting proteins armed with the docking tag. Availability of multiple imaging proteins might have tremendous implications for the development and evaluation of novel anti-cancer and, specifically, anti-angiogenic therapies.
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Humanized docking system for assembly of targeting drug delivery complexes.
Journal of Controlled Release, 2003Co-Authors: Marina V. Backer, Timur I. Gaynutdinov, Renee Aloise, Mohamed Arab, Kristen Przekop, Robert J Crouch, Inna Gorshkova, Tao Hu, Jonathan M. BackerAbstract:Abstract Targeted drug delivery requires ‘loading’ drugs onto targeting proteins. Traditional technologies for loading drugs rely on chemical conjugation of drugs or drug carriers to targeting proteins. An alternative approach might rely on assembly of targeting complexes using a docking system that includes two components: a ‘docking’ tag fused to a targeting protein, and a ‘Payload’ Module containing an adapter protein for non-covalent binding to the docking tag. We describe here a fully humanized adapter/docking tag system based on non-covalent interaction between two fragments of human pancreatic RNase I. A 15 amino acid long N-terminal fragment of RNase I designed to serve as a docking tag, was fused to the N-terminus of human vascular endothelial growth factor that served as a targeting protein. An 18–125 and an 18–127 amino acid long fragments of RNase I were engineered, expressed and refolded into active conformations to serve as adapter proteins. Interactions between the targeting and adapter proteins were characterized using enzymatic analysis and surface plasmon resonance. Targeting DNA delivery complexes were assembled, characterized by dynamic light scattering, and found to be very effective in receptor-mediated DNA delivery.
Keisuke Shinozaki - One of the best experts on this subject based on the ideXlab platform.
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Thermal and mechanical design of SPICA Payload Module
Space Telescopes and Instrumentation 2018: Optical Infrared and Millimeter Wave, 2018Co-Authors: Hiroyuki Ogawa, Keisuke Shinozaki, Takao Nakagawa, Hideo Matsuhara, Chihiro Tokoku, Mitsunobu Kawada, Ken Goto, Shinsuke Takeuchi, Masaru Saijo, Yoichi SatoAbstract:We present an overview of the thermal and mechanical design of the Payload Module (PLM) of the next- generation infrared astronomy mission Space Infrared Telescope for Cosmology and Astrophysics (SPICA). The primary design goal of PLM is to cool the whole science assembly including a 2.5 m telescope and focal-plane instruments below 8 K. SPICA is thereby expected to have very low background conditions so that it can achieve unprecedented sensitivity in the mid- and far-infrared. PLM also provides the instruments with the 4.8 K and 1.8 K stages to cool their detectors. The SPICA cryogenic system combines passive, effective radiative cooling by multiple thermal shields and active cooling by a series of mechanical cryocoolers. The mechanical cryocoolers are required to provide 40 mW cooling power at 4.8 K and 10 mW at 1.8 K at End-of-Life (EoL). End-to-end performance of the SPICA cryocooler-chain from 300 K to 50 mK was demonstrated under the framework of the ESA CryoChain Core Technology Program (CC-CTP). In this paper, we focus on the recent progress of the thermal and mechanical design of SPICA PLM which is based on the SPICA mission proposal to ESA.
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Preliminary structural design and key technology demonstration of cryogenic assembly in the next-generation infrared space telescope SPICA
Journal of Astronomical Telescopes Instruments and Systems, 2015Co-Authors: Tadahito Mizutani, Keisuke Shinozaki, Toshihiko Yamawaki, Keiji Komatsu, Hideo Matsuhara, Ken Goto, S. Takeuchi, Takao NakagawaAbstract:The infrared space telescope SPICA (Space Infrared Telescope for Cosmology and Astrophysics) is a next-generation astronomical project of the Japan Aerospace Exploration Agency, which features a 3 m class and 6 K cryogenically cooled space telescope. This paper outlines the current status for the preliminary structural design of the SPICA Payload Module. Dedicated studies were conducted for key technologies to enhance the design accuracy of the SPICA cryogenic assembly and mitigate the development risk. One of the results is described for the concept of the on-orbit truss separation mechanisms, which aim to both reduce the heat load from the main truss assembly and isolate the microvibration by changing the natural frequency of the spacecraft.
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Thermal property measurements of critical materials for SPICA Payload Module
Physics Procedia, 2015Co-Authors: Keisuke Shinozaki, Takenori Fujii, Tadahito Mizutani, Takao Nakagawa, Takashi Onaka, Hiroyuki SugitaAbstract:The Space Infrared Telescope for Cosmology and Astrophysics (SPICA) is a pre-project of JAXA in collaboration with ESA to be launched around 2025. The 3m-class infrared telescope must be below 6K, based on scientific requirements, and features effective radiant cooling into deep space at L2 point combined with a mechanical cooler system in order to cool scientific instruments as well as the telescope. The thermal design of the SPICA Payload Module must involve researching and measuring the thermophysical properties of materials in order to achieve a highly reliable cooling chain. Accordingly, all critical materials, particularly FRPs were determined and their thermal properties (thermal conductivity, specific heat, and thermal expansion) measured. Subsequently, the measured values were compared with those in literature and included in a thermal model analysis. This paper introduces details of these thermal properties measurements, comparisons with values in literature, and a thermal model analysis of the SPICA Payload Module.
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thermal study of Payload Module for the next generation infrared space telescope spica in risk mitigation phase
Cryogenics, 2014Co-Authors: Keisuke Shinozaki, Hiroyuki Sugita, Takao Nakagawa, Yoichi Sato, Kenichiro Sawada, Makiko Ando, Keiji Komatsu, Toshihiro Yamawaki, Tadahiro Mizutani, Hiroshi MurakamiAbstract:Abstract SPace Infrared telescope for Cosmology and Astrophysics (SPICA) is a pre-project of JAXA in collaboration with ESA to be launched around 2020. The SPICA is transferred into a halo orbit around the second Lagrangian point (L2) in the Sun–Earth system, which enables us to use effective radiant cooling in combination with mechanical cooling system in order to cool a 3 m large IR telescope below 6 K. At a present, a conceptional study of SPICA is underway to assess and mitigate mission’s risks; the thermal study for the risk mitigation sets a goal of a 25% margin on cooling power of 4 K/1 K temperature regions, a 25% margin on the heat load from Focal Plane Instruments (FPIs) at intermediated temperature region, to enhance the reliability of the mechanical cooler system, and to enhance feasibility of ground tests. Thermal property measurements of FRP materials are also important. This paper introduces details of the thermal design study for risk mitigation, including development of the truss separation mechanism, the cryogenic radiator, mechanical cooler system, and thermal property measurements of materials.
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Thermal study of Payload Module for the next-generation infrared space telescope SPICA in risk mitigation phase
Space Telescopes and Instrumentation 2014: Optical Infrared and Millimeter Wave, 2014Co-Authors: Keisuke Shinozaki, Hiroyuki Sugita, Tadahito Mizutani, Yoichi Sato, Kenichiro Sawada, Makiko Ando, Toshihiko Yamawaki, Keiji Komatsu, Shun Okazaki, Hiroyuki OgawaAbstract:The Space Infrared Telescope for Cosmology and Astrophysics (SPICA) is a pre-project of JAXA in collaboration with ESA to be launched around 2025. The SPICA mission is to be launched into a halo orbit around the second Lagrangian point in the Sun-Earth system, which allows us to use effective radiant cooling in combination with a mechanical cooling system in order to cool a 3m large IR telescope below 6K. The use of 4K / 1K-class Joule-Thomson coolers is proposed in order to cool the telescope and provide a 4K / 1K temperature region for Focal Plane Instruments (FPIs). This paper introduces details of the thermal design study for the SPICA Payload Module in the Risk-Mitigation-Phase (RMP), in which the activity is focused on mitigating the mission’s highest risks. As the result of the RMP activity, most of all the goals have been fully satisfied and the thermal design of the Payload Module has been dramatically improved.
Timur I. Gaynutdinov - One of the best experts on this subject based on the ideXlab platform.
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Adapter protein for site-specific conjugation of Payloads for targeted drug delivery.
Bioconjugate chemistry, 2004Co-Authors: Marina V. Backer, Timur I. Gaynutdinov, Vimal Patel, Brian T. Jehning, Eugene Myshkin, Joseph M. BackerAbstract:High-affinity interactions of two fragments of human RNase I (1−15-aa Hu-tag and 21−125-aa HuS adapter protein) can be used for assembly of targeting drug delivery complexes. In this approach, a targeting protein is expressed as a fusion protein with a 15-aa Hu-tag, while HuS is conjugated to a drug (or a drug carrier) creating a “Payload” Module, which is then bound noncovalently to the Hu-tag of the targeting protein. Although this approach eliminates chemical modifications of targeting proteins, the Payload Modules are still constructed by random cross-linking of drugs or drug carriers to an adapter protein that might lead to functional heterogeneity of the complexes. To avoid this problem, we engineered an adapter protein HuS(N88C) with an unpaired cysteine in position 88 that can be directly modified without interference with activity of assembled targeting complexes. HuS(N88C) binds Hu-tagged annexin V with KD of 50 ± 6 nM, which is comparable to that of wild-type HuS. To demonstrate the utility of ...
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imaging angiogenesis in early stages of breast cancer using a standardized radiolabeled adapter protein docked to vascular endothelial growth factor
Breast Cancer Research, 2003Co-Authors: Stefanie Mandl, Marina V. Backer, Timur I. Gaynutdinov, Joseph M. Backer, Francis G Blankenberg, Caitlin E Oconnellrodwell, Carina Mari, Jl Vanderheyden, Christopher H ContagAbstract:Tumor growth, local invasion, and metastatic dissemination are dependent on the formation of new microvessels. Angiogenesis is therefore a crucial event in tumor progression. In recent years anti-angiogenic agents have been developed as a novel approach to cancer treatment. Successful intervention with tumor angiogenesis can induce tumor vasculature regression, leading to a complete cessation of tumor growth. Clinically, however, anti-angiogenesis inhibitors have been used with marginal success. For the development of novel effective anti-angiogenic therapies it is of crucial interest, therefore, to be able to screen new treatments for both the effects on the tumor vasculature as well as the tumor burden itself. We have engineered the murine breast cancer cell line 4T1 to stably express the luciferase gene of the North American firefly. This allowed us to visualize tumor burden by in vivo bioluminescence imaging. The 4T1 mouse mammary carcinoma is derived from Balb/c mice and very closely models advanced stage (stage IV) human breast cancer in immunogenicity, metastatic properties and growth characteristics. Additionally, we have developed the adapter/docking tag system based on interactions between an 18–127 amino acid fragment of human RNase I and a 1–15 amino acid fragment of RNase I fused to a targeting protein. To visualize angiogenesis we applied to the docking system labeling vascular endothelial growth factor with 99mTc in 4T1 breast cancer tumor-bearing mice. In preliminary studies we were able to detect neovascularization in mouse breast cancer tumor nodules as small as 2–3 mm in diameter. We found that the 99mTc-labeled vascular endothelial growth factor complexes selectively and specifically bound to tumor neovasculature. We expect that 99mTc-Adapter, a broadly applicable and general humanized radionuclide imaging 'Payload' Module, can be readily employed for a non-destructive labeling of many targeting proteins armed with the docking tag. Availability of multiple imaging proteins might have tremendous implications for the development and evaluation of novel anti-cancer and, specifically, anti-angiogenic therapies.
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Humanized docking system for assembly of targeting drug delivery complexes.
Journal of Controlled Release, 2003Co-Authors: Marina V. Backer, Timur I. Gaynutdinov, Renee Aloise, Mohamed Arab, Kristen Przekop, Robert J Crouch, Inna Gorshkova, Tao Hu, Jonathan M. BackerAbstract:Abstract Targeted drug delivery requires ‘loading’ drugs onto targeting proteins. Traditional technologies for loading drugs rely on chemical conjugation of drugs or drug carriers to targeting proteins. An alternative approach might rely on assembly of targeting complexes using a docking system that includes two components: a ‘docking’ tag fused to a targeting protein, and a ‘Payload’ Module containing an adapter protein for non-covalent binding to the docking tag. We describe here a fully humanized adapter/docking tag system based on non-covalent interaction between two fragments of human pancreatic RNase I. A 15 amino acid long N-terminal fragment of RNase I designed to serve as a docking tag, was fused to the N-terminus of human vascular endothelial growth factor that served as a targeting protein. An 18–125 and an 18–127 amino acid long fragments of RNase I were engineered, expressed and refolded into active conformations to serve as adapter proteins. Interactions between the targeting and adapter proteins were characterized using enzymatic analysis and surface plasmon resonance. Targeting DNA delivery complexes were assembled, characterized by dynamic light scattering, and found to be very effective in receptor-mediated DNA delivery.
Joseph M. Backer - One of the best experts on this subject based on the ideXlab platform.
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Adapter protein for site-specific conjugation of Payloads for targeted drug delivery.
Bioconjugate chemistry, 2004Co-Authors: Marina V. Backer, Timur I. Gaynutdinov, Vimal Patel, Brian T. Jehning, Eugene Myshkin, Joseph M. BackerAbstract:High-affinity interactions of two fragments of human RNase I (1−15-aa Hu-tag and 21−125-aa HuS adapter protein) can be used for assembly of targeting drug delivery complexes. In this approach, a targeting protein is expressed as a fusion protein with a 15-aa Hu-tag, while HuS is conjugated to a drug (or a drug carrier) creating a “Payload” Module, which is then bound noncovalently to the Hu-tag of the targeting protein. Although this approach eliminates chemical modifications of targeting proteins, the Payload Modules are still constructed by random cross-linking of drugs or drug carriers to an adapter protein that might lead to functional heterogeneity of the complexes. To avoid this problem, we engineered an adapter protein HuS(N88C) with an unpaired cysteine in position 88 that can be directly modified without interference with activity of assembled targeting complexes. HuS(N88C) binds Hu-tagged annexin V with KD of 50 ± 6 nM, which is comparable to that of wild-type HuS. To demonstrate the utility of ...
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imaging angiogenesis in early stages of breast cancer using a standardized radiolabeled adapter protein docked to vascular endothelial growth factor
Breast Cancer Research, 2003Co-Authors: Stefanie Mandl, Marina V. Backer, Timur I. Gaynutdinov, Joseph M. Backer, Francis G Blankenberg, Caitlin E Oconnellrodwell, Carina Mari, Jl Vanderheyden, Christopher H ContagAbstract:Tumor growth, local invasion, and metastatic dissemination are dependent on the formation of new microvessels. Angiogenesis is therefore a crucial event in tumor progression. In recent years anti-angiogenic agents have been developed as a novel approach to cancer treatment. Successful intervention with tumor angiogenesis can induce tumor vasculature regression, leading to a complete cessation of tumor growth. Clinically, however, anti-angiogenesis inhibitors have been used with marginal success. For the development of novel effective anti-angiogenic therapies it is of crucial interest, therefore, to be able to screen new treatments for both the effects on the tumor vasculature as well as the tumor burden itself. We have engineered the murine breast cancer cell line 4T1 to stably express the luciferase gene of the North American firefly. This allowed us to visualize tumor burden by in vivo bioluminescence imaging. The 4T1 mouse mammary carcinoma is derived from Balb/c mice and very closely models advanced stage (stage IV) human breast cancer in immunogenicity, metastatic properties and growth characteristics. Additionally, we have developed the adapter/docking tag system based on interactions between an 18–127 amino acid fragment of human RNase I and a 1–15 amino acid fragment of RNase I fused to a targeting protein. To visualize angiogenesis we applied to the docking system labeling vascular endothelial growth factor with 99mTc in 4T1 breast cancer tumor-bearing mice. In preliminary studies we were able to detect neovascularization in mouse breast cancer tumor nodules as small as 2–3 mm in diameter. We found that the 99mTc-labeled vascular endothelial growth factor complexes selectively and specifically bound to tumor neovasculature. We expect that 99mTc-Adapter, a broadly applicable and general humanized radionuclide imaging 'Payload' Module, can be readily employed for a non-destructive labeling of many targeting proteins armed with the docking tag. Availability of multiple imaging proteins might have tremendous implications for the development and evaluation of novel anti-cancer and, specifically, anti-angiogenic therapies.
Takao Nakagawa - One of the best experts on this subject based on the ideXlab platform.
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Thermal and mechanical design of SPICA Payload Module
Space Telescopes and Instrumentation 2018: Optical Infrared and Millimeter Wave, 2018Co-Authors: Hiroyuki Ogawa, Keisuke Shinozaki, Takao Nakagawa, Hideo Matsuhara, Chihiro Tokoku, Mitsunobu Kawada, Ken Goto, Shinsuke Takeuchi, Masaru Saijo, Yoichi SatoAbstract:We present an overview of the thermal and mechanical design of the Payload Module (PLM) of the next- generation infrared astronomy mission Space Infrared Telescope for Cosmology and Astrophysics (SPICA). The primary design goal of PLM is to cool the whole science assembly including a 2.5 m telescope and focal-plane instruments below 8 K. SPICA is thereby expected to have very low background conditions so that it can achieve unprecedented sensitivity in the mid- and far-infrared. PLM also provides the instruments with the 4.8 K and 1.8 K stages to cool their detectors. The SPICA cryogenic system combines passive, effective radiative cooling by multiple thermal shields and active cooling by a series of mechanical cryocoolers. The mechanical cryocoolers are required to provide 40 mW cooling power at 4.8 K and 10 mW at 1.8 K at End-of-Life (EoL). End-to-end performance of the SPICA cryocooler-chain from 300 K to 50 mK was demonstrated under the framework of the ESA CryoChain Core Technology Program (CC-CTP). In this paper, we focus on the recent progress of the thermal and mechanical design of SPICA PLM which is based on the SPICA mission proposal to ESA.
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Preliminary structural design and key technology demonstration of cryogenic assembly in the next-generation infrared space telescope SPICA
Journal of Astronomical Telescopes Instruments and Systems, 2015Co-Authors: Tadahito Mizutani, Keisuke Shinozaki, Toshihiko Yamawaki, Keiji Komatsu, Hideo Matsuhara, Ken Goto, S. Takeuchi, Takao NakagawaAbstract:The infrared space telescope SPICA (Space Infrared Telescope for Cosmology and Astrophysics) is a next-generation astronomical project of the Japan Aerospace Exploration Agency, which features a 3 m class and 6 K cryogenically cooled space telescope. This paper outlines the current status for the preliminary structural design of the SPICA Payload Module. Dedicated studies were conducted for key technologies to enhance the design accuracy of the SPICA cryogenic assembly and mitigate the development risk. One of the results is described for the concept of the on-orbit truss separation mechanisms, which aim to both reduce the heat load from the main truss assembly and isolate the microvibration by changing the natural frequency of the spacecraft.
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Thermal property measurements of critical materials for SPICA Payload Module
Physics Procedia, 2015Co-Authors: Keisuke Shinozaki, Takenori Fujii, Tadahito Mizutani, Takao Nakagawa, Takashi Onaka, Hiroyuki SugitaAbstract:The Space Infrared Telescope for Cosmology and Astrophysics (SPICA) is a pre-project of JAXA in collaboration with ESA to be launched around 2025. The 3m-class infrared telescope must be below 6K, based on scientific requirements, and features effective radiant cooling into deep space at L2 point combined with a mechanical cooler system in order to cool scientific instruments as well as the telescope. The thermal design of the SPICA Payload Module must involve researching and measuring the thermophysical properties of materials in order to achieve a highly reliable cooling chain. Accordingly, all critical materials, particularly FRPs were determined and their thermal properties (thermal conductivity, specific heat, and thermal expansion) measured. Subsequently, the measured values were compared with those in literature and included in a thermal model analysis. This paper introduces details of these thermal properties measurements, comparisons with values in literature, and a thermal model analysis of the SPICA Payload Module.
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thermal study of Payload Module for the next generation infrared space telescope spica in risk mitigation phase
Cryogenics, 2014Co-Authors: Keisuke Shinozaki, Hiroyuki Sugita, Takao Nakagawa, Yoichi Sato, Kenichiro Sawada, Makiko Ando, Keiji Komatsu, Toshihiro Yamawaki, Tadahiro Mizutani, Hiroshi MurakamiAbstract:Abstract SPace Infrared telescope for Cosmology and Astrophysics (SPICA) is a pre-project of JAXA in collaboration with ESA to be launched around 2020. The SPICA is transferred into a halo orbit around the second Lagrangian point (L2) in the Sun–Earth system, which enables us to use effective radiant cooling in combination with mechanical cooling system in order to cool a 3 m large IR telescope below 6 K. At a present, a conceptional study of SPICA is underway to assess and mitigate mission’s risks; the thermal study for the risk mitigation sets a goal of a 25% margin on cooling power of 4 K/1 K temperature regions, a 25% margin on the heat load from Focal Plane Instruments (FPIs) at intermediated temperature region, to enhance the reliability of the mechanical cooler system, and to enhance feasibility of ground tests. Thermal property measurements of FRP materials are also important. This paper introduces details of the thermal design study for risk mitigation, including development of the truss separation mechanism, the cryogenic radiator, mechanical cooler system, and thermal property measurements of materials.
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Contamination control for the space infrared observatory SPICA
Space Telescopes and Instrumentation 2014: Optical Infrared and Millimeter Wave, 2014Co-Authors: Naoki Isobe, Takao Nakagawa, Yoichi Sato, Makiko Ando, Shun Okazaki, Susumu Baba, Yuka Miura, Eiji Miyazaki, Yugo Kimoto, Junichiro IshizawaAbstract:The contamination control for the next-generation space infrared observatory SPICA is presented. The optical performance of instruments on space observatories are often degraded by particulate and/or molecular contamination. Therefore, the contamination control has a potential to produce a significant risk, and it should be investigated in the risk mitigation phase of the SPICA development. The requirements from contamination- sensitive components onborad SPICA, the telescope assembly and focal plane instruments, are summarized. Possible contamination sources inside and outside the SPICA spacecraft were investigated. Based on impact on the SPICA system design, the following contamination sources were extensively studied through simulation and measurement; (1) outgassing from the Payload Module surrounding the telescope mirror and focal plane instruments, (2) contamination due to the thruster plume, and (3) environmental contamination during the integration, storage and verification phases. Although the outgas from the Payload Module and the thruster plume were estimated to produce only a negligible influence, the environmental contamination was suggested to affect significantly the telescope and focal plane instruments. Reasonable countermeasures to reduce the environmental contamination were proposed, some of which were confirmed to be actually effective.