KEIO RESEARCHERS INFORMATION SYSTEM

Licenses and Qualifications 【 Display / hide 】

Licenses and Qualifications 【 Display / hide 】

• 医師免許証, 2000.04

Research Areas 【 Display / hide 】

Research Areas 【 Display / hide 】

• Life Science / Orthopedics

Papers 【 Display / hide 】

Papers 【 Display / hide 】

• Enhanced nerve regeneration after transplantation of NCAM-positive neural crest-like cells derived from human iPSC

  Amemiya T., Ouchi T., Kimura H., Okuyama K., Phan T.Q., Iwamoto T., Nakagawa T., Matsumoto M., Nakamura M., Okano H., Nagoshi N., Shibata S.

  Inflammation and Regeneration 46 ( 1 )  2026.12

  ISSN  18809693

  　View Summary

  Background: Peripheral nerve injuries often cause persistent sensory and motor deficits, and autologous nerve grafting, the current standard, is limited by donor site morbidity and tissue availability. Human induced pluripotent stem cells (hiPSCs)-derived neural crest-like cells (NCLCs) have shown potential for nerve regeneration, but achieving high purity and safety remains a challenge. Methods: Using a mouse model of large sciatic nerve defects, we evaluated the efficacy of transplanting NCLCs triple-positive for low-affinity nerve growth factor receptor (LNGFR), thymocyte antigen 1 (THY-1), and neural cell adhesion molecule (NCAM). Purified triple-positive cells induced from hiPSC-derived neural crest lineage were seeded in the conduit with collagen gel in the transplantation group and compared the regeneration with the autograft group and the negative control group without cells. Results: NCAM-positive NCLCs promoted robust angiogenesis and recruited host Schwann cells, thereby establishing a supportive regenerative microenvironment. This facilitated axonal regrowth, thick myelination, and organized nerve architecture comparable to that of autografts. Functional recovery, assessed by electrophysiological conduction and motor performance, eventually matched autografts, with earlier improvement observed in the transplantation group. No tumor formation was detected, and the proliferative activity of transplanted cells declined over time. Selective marker-based purification likely contributed to the favorable safety profile. Conclusion: NCAM-positive NCLCs derived from hiPSCs enhance peripheral nerve regeneration through vascularization and Schwann cell-mediated remyelination, resulting in structural and functional recovery equivalent to autografts. This strategy offers a safe, scalable alternative to donor nerve harvest, and integration with bioengineered conduits could further expand clinical applicability in peripheral nerve reconstruction.

  • Access to Document (DOI)

• Quantitative assessment of ulnohumeral instability after K-NOW unlinked total elbow arthroplasty using the helical axis: a pilot study.

  Sugiura Y, Iwamoto T, Matsumoto Y, Kiyota Y, Suzuki T, Nagura T, Ogihara N, Nakamura M

  Journal of shoulder and elbow surgery  2026.07

  ISSN  1058-2746

  • Access to Document (DOI)

• 【全身の関節の解剖、39の病態、ケアの流れがこの1冊に!　整形外科の「関節」超深掘り!】(第3章)手関節　手関節で起こりやすい疾患と看護　関節リウマチ

  岩本 卓士

  整形外科看護 ((株)メディカ出版)   ( 2026夏季増刊 ) 107 - 111 2026.06

  ISSN  1342-4718

• Anatomical Reconstruction of the Terminal Tendon and Lateral Band for Severe Chronic Tendon Mallet Injury

  Suzuki T., Kiyota Y., Matsumura N., Sato K., Nakamura M., Iwamoto T.

  Journal of Hand Surgery 51 ( 1 ) 92 - 92.e7 2026.01

  ISSN  03635023

  　View Summary

  Purpose This study aimed to evaluate the clinical outcomes of surgical treatment for chronic mallet injury with severe extension lag using an anatomic reconstruction of the terminal tendon and lateral band with a palmaris longus (PL) tendon graft. Methods Eleven patients with a mean age of 52 years (range, 24–82 years) who underwent surgical reconstruction for chronic tendon mallet injuries using the PL tendon were included. The harvested PL tendon was either folded longitudinally or divided into two slips. The graft was secured to the distal phalanx using a bone anchor and sutured to the soft tissues and remnants of the original terminal tendon distal to the distal interphalangeal (DIP) joint. Each half-slip tendon was passed under the transverse retinacular ligament and sutured side-to-side to the lateral band at approximately the midpoint of the proximal phalanx. The active range of motion of the affected finger was evaluated before and after surgery, and any complications were recorded. Results Before surgery, the extension of the DIP joint averaged −49.5° (range, −40° to −60°). The postoperative mean lag of the DIP joint improved to −7.8° (range, −20° to +20°). According to the Miller classification, four patients had excellent results, four had good results, and three had fair results. Two patients who underwent folded-PL tendon grafting developed superficial dorsal skin infections on the little finger that resolved with oral antibiotics or removal of the sutures. Conclusions Anatomical reconstruction of the terminal tendon and lateral bands using a PL tendon graft yielded satisfactory outcomes in chronic tendon mallet injuries. Dividing the PL tendon into two slips is recommended to reduce the risk of postoperative infection. Type of study/level of evidence Therapeutic IV.

  • Access to Document (DOI)

• Platelet-like cells differentiated from adipose-derived mesenchymal stem cells inhibit acute inflammation of tendinopathy in rats

  Torii A., Yamada Y., Ono-Uruga Y., Sato Y., Kaneko Y., Nakamura S., Iwamoto T., Matsubara Y., Matsumoto M., Nakamura M., Sato K., Miyamoto T.

  Journal of Bone and Mineral Metabolism 44 ( 1 ) 18 - 27 2026.01

  ISSN  09148779

  　View Summary

  Introduction: Tendinopathy, a disease that causes inflammation and pain and limits patients’ activities of daily living, is considered particularly important to treat during the acute inflammatory phase to prevent the transition to chronic degeneration. Recently, platelet-rich plasma (PRP) has been used to treat tendinopathy; however, it is not clear whether platelets themselves, which are the active component of PRP, could be effective in treating tendinopathy. Materials and Methods: We made rat Achilles tendinopathy models by incision of the calcaneal attachment and administrated platelet-like cells derived from adipose-derived mesenchymal stem cells (ASCL-PLCs) to the injury site and investigated the anti-inflammatory effect. Results: ASCL-PLCs significantly inhibits the inflammatory cytokine expression and inflammatory cell infiltration in acute tendonitis in a rat Achilles tendon injury model in vivo. Interestingly, we observed no xeno-reaction when human-derived ASCL-PLCs were administered to wild-type rats in vivo. Moreover, IL-6 expression and phosphorylation seen in NIH3T3 fibroblasts treated with IL-6 plus soluble IL-6 receptor were both significantly suppressed by ASCL-PLCs in vitro. Conclusion: ASCL-PLC has advantages over existing PRP therapies, including the ability to be cryopreserved after quality checks, and homogeneous populations of ASCL-PLCs can be prepared in large quantity. We conclude that in the future ASCL-PLCs may serve as an allogeneic transplant effective to treat tendinopathy.

  • Access to Document (DOI)

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Papers, etc., Registered in KOARA 【 Display / hide 】

Papers, etc., Registered in KOARA 【 Display / hide 】

• Pathophysiology of heterotopic ossification and search for novel therapies.

  Iwamoto, Takuji

  科学研究費補助金研究成果報告書 2023

• Development of 3D printing orthosis based on CT images for finger osteoarthritis

  Iwamoto, Takuji

  科学研究費補助金研究成果報告書 2020

• The establishment of computer assisted surgery for total elbow arthroplasty

  Iwamoto, Takuji

  科学研究費補助金研究成果報告書 2017

• Detection of specific antibody in patients with rheumatoid arthritis negative for anti-CCP antibody

  Iwamoto, Takuji

  科学研究費補助金研究成果報告書 2012

Reviews, Commentaries, etc. 【 Display / hide 】

Reviews, Commentaries, etc. 【 Display / hide 】

• RSA機種選択の変遷　私の場合

  松村 昇, 赤尾 翔太郎, 川崎 みづ紀, 田邉 優, 清田 康弘, 大木 聡, 鈴木 拓, 松本 守雄, 中村 雅也, 岩本 卓士

  日本整形外科学会雑誌 ((公社)日本整形外科学会)  100 ( 2 ) S447 - S447 2026.03

  ISSN  0021-5325

• 空間トランスクリプトーム解析を用いた治療抵抗性関節リウマチの病態解明

  石原 啓成, 浅野 達雄, 岩本 卓士, 中村 雅也, 高柳 広

  日本リウマチ学会総会・学術集会プログラム・抄録集 ((一社)日本リウマチ学会)  70回   726 - 726 2026.03

• 疾患活動性をコントロール可能な時代のリウマチ手術タイミング　関節リウマチによる肘関節障害に対する手術適応と治療選択

  岩本 卓士, 清田 康弘, 大木 聡, 鈴木 拓, 松村 昇, 佐藤 和毅, 松本 守雄, 中村 雅也

  日本整形外科学会雑誌 ((公社)日本整形外科学会)  100 ( 3 ) S657 - S657 2026.03

  ISSN  0021-5325

• 母指CM関節症に対するsuture-button suspensionplasty　鏡視下と直視下大菱形骨部分切除の比較検討

  清田 康弘, 大木 聡, 鈴木 拓, 中山 政憲, 松村 昇, 佐藤 和毅, 松本 守雄, 中村 雅也, 岩本 卓士

  日本整形外科学会雑誌 ((公社)日本整形外科学会)  100 ( 3 ) S1195 - S1195 2026.03

  ISSN  0021-5325

• リウマチ手肘の最新治療戦略　患者ニーズに基づく個別化アプローチ

  岩本 卓士

  日本リウマチ学会総会・学術集会プログラム・抄録集 ((一社)日本リウマチ学会)  70回   997 - 997 2026.03

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Research Projects of Competitive Funds, etc. 【 Display / hide 】

Research Projects of Competitive Funds, etc. 【 Display / hide 】

• ヒトiPS細胞由来神経突起束を用いた人工神経の規格化に向けた研究

  2024.04

  -

  2027.03

  基盤研究(C), Principal investigator

• 外傷性異所性骨化の病態解明と新規治療法の探索

  2021.04

  -

  2024.03

  MEXT,JSPS, Grant-in-Aid for Scientific Research, Grant-in-Aid for Scientific Research (C), Principal investigator

• 手指変形性関節症に対するCT画像に基づく３Dプリンティング治療装具の開発

  2018.04

  -

  2021.03

  MEXT,JSPS, Grant-in-Aid for Scientific Research, Grant-in-Aid for Scientific Research (C), Principal investigator

• The establishment of computer assisted surgery for total elbow arthroplasty

  2015.04

  -

  2018.03

  MEXT,JSPS, Grant-in-Aid for Scientific Research, Grant-in-Aid for Scientific Research (C), Principal investigator

Courses Taught 【 Display / hide 】

Courses Taught 【 Display / hide 】

• LECTURE SERIES, ORTHOPAEDICS

  2026

• CLINICAL CLERKSHIP IN ORTHOPAEDICS

  2026

• PATHOPHYSIOLOGICAL ISSUES IN ACUTE CARE

  2026

• PATHOPHYSIOLOGICAL ISSUES IN ACUTE CARE

  2025

• LECTURE SERIES, ORTHOPAEDICS

  2025

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Memberships in Academic Societies 【 Display / hide 】

Memberships in Academic Societies 【 Display / hide 】

• 日本整形外科学会

  　

• 日本リウマチ学会

  　

• 日本手外科学会

  　

• 日本肘関節学会

  　

• 日本人工関節学会