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Dive into the research topics where Yasutaka Aoyama is active.

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Featured researches published by Yasutaka Aoyama.


Leukemia | 2012

CD138-negative clonogenic cells are plasma cells but not B cells in some multiple myeloma patients

Naoki Hosen; Yoshikazu Matsuoka; S Kishida; Jun Nakata; Y Mizutani; Kana Hasegawa; Atsuko Mugitani; Hiroyoshi Ichihara; Yasutaka Aoyama; Sumiyuki Nishida; Akihiro Tsuboi; Fumihiro Fujiki; Naoya Tatsumi; Hiroko Nakajima; Masayuki Hino; Tadashi Kimura; Kenichiro Yata; Masahiro Abe; Yoshihiro Oka; Yusuke Oji; Atsushi Kumanogoh; Haruo Sugiyama

Clonogenic multiple myeloma (MM) cells reportedly lacked expression of plasma cell marker CD138. It was also shown that CD19+ clonotypic B cells can serve as MM progenitor cells in some patients. However, it is unclear whether CD138-negative clonogenic MM plasma cells are identical to clonotypic CD19+ B cells. We found that in vitro MM colony-forming cells were enriched in CD138−CD19−CD38++ plasma cells, while CD19+ B cells never formed MM colonies in 16 samples examined in this study. We next used the SCID-rab model, which enables engraftment of human MM in vivo. CD138−CD19−CD38++ plasma cells engrafted in this model rapidly propagated MM in 3 out of 9 cases, while no engraftment of CD19+ B cells was detected. In 4 out of 9 cases, CD138+ plasma cells propagated MM, although more slowly than CD138− cells. Finally, we transplanted CD19+ B cells from 13 MM patients into NOD/SCID IL2Rγc−/− mice, but MM did not develop. These results suggest that at least in some MM patients CD138-negative clonogenic cells are plasma cells rather than B cells, and that MM plasma cells including CD138− and CD138+ cells have the potential to propagate MM clones in vivo in the absence of CD19+ B cells.


Leukemia & Lymphoma | 2003

Infliximab for the treatment of severe steroid refractory acute graft-versus-host disease in three patients after allogeneic hematopoietic transplantation.

Takahisa Yamane; Ryousuke Yamamura; Yasutaka Aoyama; Hirohisa Nakamae; Taro Hasegawa; Chikahiko Sakamoto; Hisako Shibata; Yoshiki Terada; Genju Koh; Mayasuki Hino

Acute graft-versus-host disease (aGVHD) is a serious complication of allogeneic peripheral blood stem cell transplantation (PBSCT). Patients with severe aGVHD not responding to treatment with steroids have a poor prognosis. We treated three patients with severe aGVHD refractory to steroids with infliximab. Patients (MDS 1, NHL 1, ALL 1) developed grade II-IV GVHD at a median of 13 days (range 9–17) after non-myeloablative PBSCT (HLA mismatched). All patients had received treatment with high-dose steroids for a median of 7 days (range 7–10) in addition to mycophenolate mofetil (MMF) (one). Infliximab was given in 3 weekly doses of 5 mg/kg. In one of three patients a partial resolution of diarrhea and minor improvement of skin were observed. One patient died with refractory GVHD. Infliximab is apparently an effective drug for the treatment of aGVHD, but can be more effective at doses of 5 mg/kg or higher and/or by administering it repeatedly every week.


International Journal of Hematology | 2007

The prophylactic effect of itraconazole capsules and fluconazole capsules for systemic fungal infections in patients with acute myeloid leukemia and myelodysplastic syndromes: A Japanese multicenter randomized, controlled study

Yoshikazu Ito; Kazuma Ohyashiki; Isao Yoshida; Makoto Takeuchi; Yasutaka Aoyama; Atsuko Mugitani; Yasuhiro Matsuura; Hisashi Wakita; Mitsuhiro Matsuda; Erina Sakamoto; Toru Kiguchi; Akio Urabe; Kazuo Tamura; Akihisa Kanamaru; Toru Masaoka

We performed a randomized, controlled study comparing the prophylactic effects of capsule forms of fluconazole (n = 110) and itraconazole (n = 108) in patients with acute myeloid leukemia (AML) or myelodysplastic syndromes (MDS) during and after chemotherapy.There were 4 cases with possible systemic fungal infection in the itraconazole group, and there were 8 possible and 3 probable cases in the fluconazole group. Adverse events did not significantly differ in the 2 groups. In patients with MDS or in the remission-induction phase of chemotherapy, the numbers of cases with probable or possible infections were lower in the itraconazole group than in the fluconazole group, whereas no difference was seen in patients with AML or in the consolidation phase of therapy. In patients with neutrophil counts of <0.1 * 109/L lasting for more than 4 weeks, the frequency of infection in the fluconazole group (5 of 9 patients) was significantly higher than in the itraconazole group (0 of 7 patients; P = .03). Our results suggest that both drugs were well tolerated in patients with AML or MDS who received chemotherapy and that the efficacy of itraconazole for prophylaxis against systemic fungal disease is not inferior to that of fluconazole.


International Journal of Hematology | 2009

Efficacy and safety of intravenous itraconazole as empirical antifungal therapy for persistent fever in neutropenic patients with hematological malignancies in Japan

Kensuke Ohta; Saori Kosaka; Yoshitaka Nakao; Takeo Kumura; Kiyomichi Hagihara; Erina Sakamoto; Shuichiro Okamoto; Asao Hirose; Yasutaka Aoyama; Ryousuke Yamamura; Yukari Umemoto; Yoshiki Terada; Yasunobu Takeoka; Takahiko Nakane; Hideo Koh; Masayuki Hino

Recently, empirical antifungal therapy with intravenous itraconazole (ITCZ) for neutropenic patients with antibiotics-resistant fever has been approved by Japanese Ministry of Health, Labour and Welfare on the bases of previous multicenter trials of foreign countries. In this study, we conducted a single-arm, multicenter, prospective study in order to evaluate the efficacy of empirical ITCZ injection on Japanese patients. Sixty-eight patients with hematological diseases who underwent anticancer chemotherapy or stem cell transplantation were enrolled. In this study, we found that the overall clinical response rate to ITCZ injection was 67.6% and success rate of achieving composite endpoints including survival, defervescence during neutropenia, no breakthrough fungal infections, and no premature discontinuation of drug was 50.0%. Mild adverse reactions were observed in 6 patients (8.8%). Further analysis revealed that possible/probable deep fungal infection according to the 2002 and 2008 criteria defined by EORTC/MSG were found in 19.1 and 7.5% of the patients, respectively. Interestingly, response rate to ITCZ injection of possible/probable cases according to the 2002 and 2008 criteria was 61.5% (8/13) and 100% (5/5), respectively. These results not only proved the good efficacy and safety of empirical ITCZ injection for Japanese patients, but also indicated a utility of the drug on future “presumptive” approach.


Vox Sanguinis | 2001

Primary refractoriness to platelet transfusion caused by Naka antibody alone

H. Fujino; Kensuke Ohta; Atsuko Taniue; Nobuo Nagao; Masayuki Hino; Takahisa Yamane; Ki-Ryang Koh; Yasunobu Takeoka; Asao Hirose; Yasutaka Aoyama; Hirohisa Nakamae; Yoshiki Terada; Takayuki Takubo; Noriyuki Tatsumi

Anti‐Naka, a platelet‐specific antibody, occasionally causes platelet‐transfusion refractoriness (PTR) together with human leucocyte antigen (HLA) antibodies. Anti‐Naka usually appears after frequent platelet transfusions or pregnancy. We report the first case of PTR caused by anti‐Naka alone.


Annals of Hematology | 2001

Virus-associated hemophagocytic syndrome due to rubella virus and varicella-zoster virus dual infection in patient with adult idiopathic thrombocytopenic purpura

Yasunobu Takeoka; Masayuki Hino; Oiso N; Nishi S; Ki-Ryang Koh; Takahisa Yamane; Kensuke Ohta; Hirohisa Nakamae; Yasutaka Aoyama; Asao Hirose; H. Fujino; Takayuki Takubo; T. Inoue; Noriyuki Tatsumi

Abstract. A 26-year-old woman with idiopathic thrombocytopenic purpura (ITP) was admitted to our hospital because of fever and rash. Blood tests revealed thrombocytopenia, liver dysfunction, coagulopathy, and hyperferritinemia. Bone marrow examination revealed many atypical lymphocytes and some histiocytes with hemophagocytosis. On admission she was diagnosed with rubella virus-associated hemophagocytic syndrome (VHAS), but on laboratory examination, she was seropositive for varicella-zoster virus (VZV)-IgM as well as rubella virus-IgM. She was therefore diagnosed with dual infection by rubella virus and VZV. Her simultaneous rubella virus and VZV infection may have been related to the VAHS pathogenesis. She was treated with prednisolone and gamma globulin therapy and recovered completely.


Clinical Drug Investigation | 2000

A Case of Rhabdomyolysis due to Levofloxacin

Hirohisa Nakamae; Masayuki Hino; Takahisa Yamane; Kensuke Ohta; Yasutaka Aoyama; Takeo Kumura; Yuichi Sannomiya; Noriyuki Tatsumi

Quinolone antibacterial agents, which are broad-spectrum drugs with excellent antibacterial activity, have been used widely to treat various bacterial infections in the clinical setting. However, the adverse effects of these drugs on the musculoskeletal system have been observed at an incidence of 1% or less, and consist mainly of myalgia and arthralgia, although tendon disorders have also recently been reported.[1-4] This report highlights a case of rhabdomyolysis induced by levofloxacin.


Acta Haematologica | 2001

Nodal Gamma/Delta T Cell Lymphoma in Complete Remission following Allogeneic Bone Marrow Transplantation from an HLA-Matched Unrelated Donor

Yasutaka Aoyama; Takahisa Yamane; Masayuki Hino; Kensuke Ota; Taro Hasegawa; Chikahiko Sakamoto; Hirohisa Nakamae; Ryousuke Yamamura; Ki-Ryang Koh; Takayuki Takubo; Takeshi Inoue; Kazuo Tsubaki; Noriyuki Tatsumi

Gamma/delta T cell lymphoma is very rare, and usually occurs as an extranodal tumor. We describe the case of a 16-year-old Japanese man with an unusual nodal gamma/delta T cell lymphoma with generalized lymphadenopathy and bone marrow involvement. No tumor involvement was observed in the liver, spleen, or nasal cavity. Examination for surface antigens on lymphoma cells revealed a unique phenotype, positive for CD3 and T cell receptor (TCR) gamma/delta, but negative for CD2. Genotypic analysis revealed the tumor to be of monoclonal origin and characterized by TCR gamma-chain gene rearrangement, but there was no rearrangement of the TCR beta-chain gene. Our patient’s tumor responded to combination chemotherapy and subsequent allogeneic bone marrow transplantation from an HLA-matched unrelated donor. He has remained well and free of disease for 35 months.


Nature Medicine | 2017

The activated conformation of integrin β7 is a novel multiple myeloma-specific target for CAR T cell therapy

Naoki Hosen; Yukiko Matsunaga; Kana Hasegawa; Hiroshi Matsuno; Yuki Nakamura; Mio Makita; Kouki Watanabe; Mikako Yoshida; Kei Satoh; Soyoko Morimoto; Fumihiro Fujiki; Hiroko Nakajima; Jun Nakata; Sumiyuki Nishida; Akihiro Tsuboi; Yoshihiro Oka; Masahiro Manabe; Hiroyoshi Ichihara; Yasutaka Aoyama; Atsuko Mugitani; Takafumi Nakao; Masayuki Hino; Ryosuke Uchibori; Keiya Ozawa; Yoshihiro Baba; Seitaro Terakura; Naoki Wada; Eiichi Morii; Junichi Nishimura; Kiyoshi Takeda

Cancer-specific cell-surface antigens are ideal targets for monoclonal antibody (mAb)-based immunotherapy but are likely to have previously been identified in transcriptome or proteome analyses. Here, we show that the active conformer of an integrin can serve as a specific therapeutic target for multiple myeloma (MM). We screened >10,000 anti-MM mAb clones and identified MMG49 as an MM-specific mAb specifically recognizing a subset of integrin β7 molecules. The MMG49 epitope, in the N-terminal region of the β7 chain, is predicted to be inaccessible in the resting integrin conformer but exposed in the active conformation. Elevated expression and constitutive activation of integrin β7 conferred high MMG49 reactivity on MM cells, whereas MMG49 binding was scarcely detectable in other cell types including normal integrin β7+ lymphocytes. T cells transduced with MMG49-derived chimeric antigen receptor (CAR) exerted anti-MM effects without damaging normal hematopoietic cells. Thus, MMG49 CAR T cell therapy is promising for MM, and a receptor protein with a rare but physiologically relevant conformation can serve as a cancer immunotherapy target.


Nature Genetics | 2016

Corrigendum: Recurrent DUX4 fusions in B cell acute lymphoblastic leukemia of adolescents and young adults

Takahiko Yasuda; Shinobu Tsuzuki; Masahito Kawazu; Fumihiko Hayakawa; Shinya Kojima; Toshihide Ueno; Naoto Imoto; Shinji Kohsaka; Akiko Kunita; Koichiro Doi; Toru Sakura; Toshiaki Yujiri; Eisei Kondo; Katsumichi Fujimaki; Yasunori Ueda; Yasutaka Aoyama; Shigeki Ohtake; Junko Takita; Eirin Sai; Masafumi Taniwaki; Mineo Kurokawa; Shinichi Morishita; Masashi Fukayama; Hitoshi Kiyoi; Yasushi Miyazaki; Tomoki Naoe; Hiroyuki Mano

Nat. Genet. 48, 569–574 (2016); published online 28 March 2016; corrected after print 29 August 2016 In the version of this article initially published, the following statement was not included in the Online Methods: “The results published here are in part based upon data generated by the TARGET initiative managed by the National Cancer Institute (NCI).

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