Kyushu University Academic Staff Educational and Research Activities Database
List of Papers
Akihiko Numata Last modified date:2021.06.13

Assistant Professor / Hematology, Oncology & Cardiovascular medicine / Kyushu University Hospital


Papers
1. Numata, Akihiko; Kwok, Hui Si; Zhou, Qi-Ling; Li, Jia; Tirado-Magallanes, Roberto; Angarica, Vladimir Espinosa; Hannah, Rebecca; Park, Jihye; Wang, Chelsia Qiuxia; Krishnan, Vaidehi; Rajagopalan, Deepa; Zhang, Yanzhou; Zhou, Siqin; Welner, Robert S.; Osato, Motomi; Jha, Sudhakar; Bohlander, Stefan K.; Gottgens, Berthold; Yang, Henry; Benoukraf, Touati; Lough, John W.; Bararia, Deepak; Tenen, Daniel G., Lysine acetyltransferase Tip60 is required for hematopoietic stem cell maintenance, BLOOD, 10.1182/blood.2019001279, 136, 15, 1735-1747, 2020.10.
2. Goichi Yoshimoto, Yasuo Mori, Koji Kato, Takahiro Shima, Kohta Miyawaki, Yoshikane Kikushige, Kenjiro Kamezaki, Akihiko Numata, Takahiro Maeda, Katsuto Takenaka, Hiromi Iwasaki, Takanori Teshima, Koichi Akashi, Toshihiro Miyamoto, Human Herpes Virus-6–Associated Encephalitis/Myelitis Mimicking Calcineurin Inhibitor–Induced Pain Syndrome in Allogeneic Stem Cell Transplantation Recipients, Biology of Blood and Marrow Transplantation, 10.1016/j.bbmt.2018.07.017, 24, 12, 2540-2548, 2018.12, Human herpes virus-6 (HHV6)-associated myelitis and calcineurin inhibitor–induced pain syndrome (CIPS) are serious complications of allogeneic hematopoietic stem cell transplantation (allo-HSCT). Because these 2 complications cause similar sensory nerve–related symptoms, such as paresthesia, pruritus, and severe pain occurring around the engraftment, it can be difficult to differentially diagnose the 2 conditions. We retrospectively analyzed 435 recipients to distinguish clinical symptoms of these 2 complications. Twenty-four patients (5.5%) developed HHV6-associated encephalitis/myelitis; of these, 11 (2.5%) presented only with myelitis-related symptoms (HHV6-associated myelitis), which was confirmed by the detection of HHV6 DNA, and 8 (1.8%) had CIPS, with undetected HHV6 DNA. All patients with HHV6-associated myelitis or CIPS exhibited similar sensory nerve–related symptoms. Diagnostic images did not provide definite evidence specific for each disease. Symptoms of all patients with CIPS improved after switching to another immunosuppressant. Overall survival rate at 2 years for patients with HHV6-associated encephalitis/myelitis was significantly lower than that of CIPS (13.1% versus 29.2%; P =.049) or that of patients without HHV6-associated encephalitis/myelitis or CIPS (42.4%; P =.036), whereas there was no significant difference among the latter 2 groups (P =.889). The development of HHV6-associated encephalitis/myelitis but not CIPS was significantly associated with poor prognosis. Thus, transplant physicians should be aware that sensory nerve–related symptoms indicate early manifestations that might be correlated with reactivation of HHV6 or CIPS. Therefore, identification of HHV6 DNA is crucial for making a differential diagnosis and immediately starting appropriate treatments for each complication..
3. Yasuo Mori, Goichi Yoshimoto, Ruriko Nishida, Takeshi Sugio, Kohta Miyawaki, Takahiro Shima, Yoji Nagasaki, Noriko Miyake, Yukiko Harada, Yuya Kunisaki, Kenjiro Kamezaki, Akihiko Numata, Koji Kato, Motoaki Shiratsuchi, Takahiro Maeda, Katsuto Takenaka, Hiromi Iwasaki, Nobuyuki Shimono, Koichi Akashi, Toshihiro Miyamoto, Gastrointestinal Graft-versus-Host Disease Is a Risk Factor for Postengraftment Bloodstream Infection in Allogeneic Hematopoietic Stem Cell Transplant Recipients, Biology of Blood and Marrow Transplantation, 10.1016/j.bbmt.2018.06.002, 24, 11, 2302-2309, 2018.11, Bloodstream infection (BSI) is a well-known cause of morbidity and mortality in allogeneic hematopoietic stem cell transplant (allo-HSCT) recipients. Here, we conducted a retrospective study to assess the morbidity, etiology, risk factors, and outcomes of BSI in the postengraftment period (PE-BSI) after allo-HSCT. Forty-three of 316 patients (13.6%) developed 57 PE-BSI episodes, in which 62 pathogens were isolated: Gram-positive bacteria, gram-negative bacteria, and fungi, respectively, accounted for 54.8%, 35.5%, and 9.7% of the isolates. Multivariate analysis revealed methylprednisolone use for graft-versus-host disease (GVHD) prophylaxis (odds ratio [OR], 6.49; 95% confidence interval [CI], 1.49 to 28.2; P =.013) and acute gastrointestinal GVHD (GI-GVHD) (OR, 8.82; 95% CI, 3.99 to 19.5; P <.0001) as risk factors for developing PE-BSI. This finding suggested that GI-GVHD increases the risk of bacterial translocation and subsequent septicemia. Moreover, among patients with GI-GVHD, insufficient response to corticosteroids, presumably related to an intestinal dysbiosis, significantly correlated with this complication. Patients with PE-BSI presented worse outcome compared with those without (3-year overall survival, 47.0% versus 18.6%; P <.001). Close microbiologic monitoring for BSIs and minimizing intestinal dysbiosis may be crucial to break the vicious cycle between GI-GVHD and bacteremia and to improve transplant outcomes especially in patients who require additional immunosuppressants..
4. Akihiko Numata, Hui Si Kwok, Akira Kawasaki, Jia Li, Qi Ling Zhou, Jon Kerry, Touati Benoukraf, Deepak Bararia, Feng Li, Erica Ballabio, Marta Tapia, Aniruddha J. Deshpande, Robert S. Welner, Ruud Delwel, Henry Yang, Thomas A. Milne, Reshma Taneja, Daniel G. Tenen, The basic helix-loop-helix transcription factor SHARP1 is an oncogenic driver in MLL-AF6 acute myelogenous leukemia, Nature Communications, 10.1038/s41467-018-03854-0, 9, 1, 2018.04, Acute Myeloid Leukemia (AML) with MLL gene rearrangements demonstrate unique gene expression profiles driven by MLL-fusion proteins. Here, we identify the circadian clock transcription factor SHARP1 as a novel oncogenic target in MLL-AF6 AML, which has the worst prognosis among all subtypes of MLL-rearranged AMLs. SHARP1 is expressed solely in MLL-AF6 AML, and its expression is regulated directly by MLL-AF6/DOT1L. Suppression of SHARP1 induces robust apoptosis of human MLL-AF6 AML cells. Genetic deletion in mice delays the development of leukemia and attenuated leukemia-initiating potential, while sparing normal hematopoiesis. Mechanistically, SHARP1 binds to transcriptionally active chromatin across the genome and activates genes critical for cell survival as well as key oncogenic targets of MLL-AF6. Our findings demonstrate the unique oncogenic role for SHARP1 in MLL-AF6 AML..
5. Shuro Yoshida, Hideho Henzan, Toshiyuki Ueno, Takuya Shimakawa, Yayoi Matsuo, Takuro Kuriyama, Noriyuki Saito, Ichiro Kawano, Akihiko Numata, Ken Takase, Tadafumi Iino, Tetsuya Eto, The confirmation of safety for the intensified conditioning regimens
A retrospective study of allogeneic hematopoietic stem cell transplantation for non-remission hematological malignant diseases, International Journal of Hematology-Oncology and Stem Cell Research, 12, 2, 123-131, 2018.01, Background: The prognosis of allogeneic hematopoietic stem cell transplantation (HSCT) for non-remission hematological malignant diseases is usually unfavorable. The most uncontrollable factor is residual disease or relapse. To overcome this problem, intensified conditioning regimens-sequential and/or additional chemotherapy to the standard regimen-could be effective. However, increasing the intensity of conditioning might also lead to more complications. Materials and Methods: We retrospectively analyzed 81 patients with non-remission disease who received allogeneic HSCT in our institution between 2007 and 2011. Results: 55.6% in 36 myeloablative conditioning patients and 46.7% in 45 reduced-intensity conditioning patients received intensified conditioning. The 5-year probability of overall survival was 35.0% and 17.1% in the standard and intensified group, respectively (p=0.027). Relapse mortality was 30% in the standard regimen group and 36.6% in the intensified regimen group (p=0.54). Transplant-related mortality (TRM) at 30 and 100 days was 5%, 17.1% (p=0.086) and 27.5%, 34.2% (p=0.52) in the standard and intensified group, respectively. There was no difference in TRM between the 2 groups at 30 days and 100 days. Conclusion: The results of the study confirm the safety of the intensified conditioning regimen. Meanwhile, it could be considered as one of the few methods available to reduce the tumor burden before HSCT for refractory malignant diseases..
6. Deepak Bararia, Hui Si Kwok, Robert S. Welner, Akihiko Numata, Menyhárt B. Sárosi, Henry Yang, Sheena Wee, Sebastian Tschuri, Debleena Ray, Oliver Weigert, Elena Levantini, Alexander K. Ebralidze, Jayantha Gunaratne, Daniel G. Tenen, Acetylation of C/EBPα inhibits its granulopoietic function, Nature communications, 10.1038/ncomms10968, 7, 2016.03, CCAAT/enhancer-binding protein alpha (C/EBPα) is an essential transcription factor for myeloid lineage commitment. Here we demonstrate that acetylation of C/EBPα at lysine residues K298 and K302, mediated at least in part by general control non-derepressible 5 (GCN5), impairs C/EBPα DNA-binding ability and modulates C/EBPα transcriptional activity. Acetylated C/EBPα is enriched in human myeloid leukaemia cell lines and acute myeloid leukaemia (AML) samples, and downregulated upon granulocyte-colony stimulating factor (G-CSF)- mediated granulocytic differentiation of 32Dcl3 cells. C/EBPα mutants that mimic acetylation failed to induce granulocytic differentiation in C/EBPα-dependent assays, in both cell lines and in primary hematopoietic cells. Our data uncover GCN5 as a negative regulator of C/EBPα and demonstrate the importance of C/EBPα acetylation in myeloid differentiation..
7. Zahra Kabiri, Akihiko Numata, Akira Kawasaki, Edison, Daniel G. Tenen, David M. Virshup, Wnts are dispensable for differentiation and self-renewal of adult murine hematopoietic stem cells, Blood, 10.1182/blood-2014-09-598540, 126, 9, 1086-1094, 2015.08, Wnt signaling controls early embryonic hematopoiesis and dysregulated β-catenin is implicated in leukemia. However, the role of Wnts and their source in adult hematopoiesis is still unclear, and is clinically important as upstream Wnt inhibitors enter clinical trials. We blocked Wnt secretion in hematopoietic lineages by targeting Porcn, a membrane-bound O-acyltransferase that is indispensable for the activity and secretion of all vertebrate Wnts. Surprisingly, deletion of Porcn in Rosa-CreERT2/PorcnDel, MX1-Cre/PorcnDel, and Vav-Cre/PorcnDel mice had no effects on proliferation, differentiation, or self-renewal of adult hematopoietic stem cells. Targeting Wnt secretion in the bone marrow niche by treatment with a PORCN inhibitor, C59, similarly had no effect on hematopoiesis. These results exclude a role for hematopoietic PORCN-dependent Wnts in adult hematopoiesis. Clinical use of upstream Wnt inhibitors is not likely to be limited by effects on hematopoiesis..
8. Hiromitsu Daisaki, Ukihide Tateishi, Takashi Terauchi, Mitsuaki Tatsumi, Kazufumi Suzuki, Naoki Shimada, Hiroyuki Nishida, Akihiko Numata, Koji Kato, Koichi Akashi, Mine Harada, Standardization of image quality across multiple centers by optimization of acquisition and reconstruction parameters with interim FDG-PET/CT for evaluating diffuse large B cell lymphoma, Annals of Nuclear Medicine, 10.1007/s12149-012-0676-2, 27, 3, 225-232, 2013.04, Objective: A multicenter trial is currently underway using FDG-PET/CT to evaluate diffuse large B cell lymphoma in Japan (JSCT NHL10). Standardization of the image quality between the participating centers is a fundamental aspect of the study. Within the framework of JSCT NHL10, standardization of the image quality was attempted by optimizing the acquisition and reconstruction conditions using mid-therapy FDG-PET/CT for diffuse large B cell lymphoma. This report describes the procedures and results of this attempt. Methods: The acquisition protocols and imaging quality were initially determined at each center and again after modification. The image quality was based on performance with an 18F-filled National Electrical Manufacturers Association standards body phantom. We determined that the acquisition duration and reconstruction parameters of each scanner evaluated were in compliance with the Japanese guideline for the oncology FDG-PET/CT data acquisition protocol: synopsis of Version 1.0 (the Guideline) based on the results of the phantom experiments performed by the Core Laboratory. Results: A total of 18 centers (19 scanners) participated in this trial. The center's default protocol was unchanged for 9 scanners (47.4 %) and changed for 10 scanners (52.6 %). Both acquisition duration and reconstruction parameters were changed in 3 (15.8 %) of 10 scanners and the acquisition duration alone was changed in 7 (36.8 %) scanners. Also, the accuracy of the standardized uptake value (SUV) was evaluated with the acceptable level 1.0 ± 0.1, resulting in readjustment and recalibration in 2 scanners (10.5 %), which were confirmed to attain the acceptable accuracy after the required readjustment. As of August 2012, 21 patients have undergone an FDG-PET/CT examination under the acquisition protocols determined by the Core Laboratory. Evaluation of the image quality using several physical parameters confirmed that the accumulated data were of sufficient quality. Conclusions: Optimization of the acquisition protocol, in compliance with the guideline, was successfully achieved by the Core Laboratory in the framework of JSCT NHL10 to accumulate equivalent quality data across multiple centers. The progress of the trial was greatly facilitated by support from the Japan Society of Nuclear Medicine Working Group for Investigation of Response Evaluation Criteria in Malignant Tumors Using Standardized PET/CT (Principal Investigator: Ukihide Tateishi, MD., PhD)..
9. Takahiro Shima, Toshihiro Miyamoto, Yoshikane Kikushige, Yasuo Mori, Kenjiro Kamezaki, Ken Takase, Hideho Henzan, Akihiko Numata, Yoshikiyo Ito, Katsuto Takenaka, Hiromi Iwasaki, Tomohiko Kamimura, Tetsuya Eto, Koji Nagafuji, Takanori Teshima, Koji Kato, Koichi Akashi, Quantitation of hematogones at the time of engraftment is a useful prognostic indicator in allogeneic hematopoietic stem cell transplantation, Blood, 10.1182/blood-2012-02-409607, 121, 5, 840-848, 2013.01, Transient marrow expansion of normal B-cell precursors, termed hematogones, is occasionally observed after hematopoietic stem cell transplantation (HSCT). To understand the clinical significance of this phenomenon, we enumerated hematogones in 108 consecutive patients who received allogeneic HSCT for the treatment of hematologic malignancies, including acute myelogenous leukemia, advanced myelodysplastic syndromes, acute lymphoblastic leukemia, and non-Hodgkin lymphoma. Hematogone quantitation was performed at the time of complete donor engraftment (median day 25 and 32 in patients who received bone marrow and cord blood cell transplants, respectively). Hematogones were polyclonal B cells, and their frequencies correlated positively with blood B-cell numbers, and inversely with donors' but not recipients' age, suggesting that hematogones reflect cell-intrinsic B-cell potential of donor cells. Interestingly, patients developing hematogones that comprised > 5% of bone marrow mononuclear cells constituted a group with significantly prolonged overall survival and relapse-free survival, irrespective of their primary disease or donor cell source. In addition, patients with > 5% hematogones developed severe acute graft-versus-host diseases less frequently, which may contribute toward their improved survival. We therefore conclude that the amount of hematogones at the time of engraftment may be a useful tool in predicting the prognosis of patients treated with allogeneic HSCT..
10. Tomohiko Kamimura, Toshihiro Miyamoto, Noriaki Kawano, Akihiko Numata, Yoshikiyo Ito, Yong Chong, Koji Nagafuji, Takanori Teshima, Shin Hayashi, Koichi Akashi, Successful treatment by donor lymphocyte infusion of adult T-cell leukemia/lymphoma relapse following allogeneic hematopoietic stem cell transplantation, International journal of hematology, 10.1007/s12185-012-1056-3, 95, 6, 725-730, 2012.06, Adult T-cell leukemia/lymphoma (ATLL) is a highly aggressive hematologic neoplasm that has an extremely poor prognosis; however, this has improved following recent progress in allogeneic hematopoietic stem cell transplantation (allo-HSCT). Several clinical studies have shown that discontinuation of immunosuppressant therapy induces durable remission in a significant number of post-transplant relapsed patients, suggesting that ATLL may be susceptible to a graft-versus-leukemia effect. Here, we report two cases with ATLL who received donor lymphocyte infusions (DLIs) for relapse after allo-HSCT; one patient achieved complete remission (CR) after a single DLI, and the other suffered repeated relapses and was treated with chemotherapy and radiotherapy combined with a total of five rounds of DLIs. Both patients presented with exacerbation of the graft-versus-host disease after the DLIs, and remained in CR for 9 and 8 years, respectively. These data support the use of DLIs as an effective therapy to induce durable CR in the treatment of relapsed ATLL. In this study, we review previous reports and discuss the role of DLIs in the treatment of post-transplant relapsed ATLL..
11. T. Kamimura, T. Miyamoto, K. Nagafuji, A. Numata, H. Henzan, K. Takase, Y. Ito, Y. Ohno, T. Fujisaki, T. Eto, Y. Takamatsu, T. Teshima, H. Gondo, K. Akashi, S. Taniguchi, M. Harada, Role of autotransplantation in the treatment of acute promyelocytic leukemia patients in remission
Fukuoka BMT Group observations and a literature review, Bone Marrow Transplantation, 10.1038/bmt.2010.207, 46, 6, 820-826, 2011.06, We retrospectively analyzed the outcomes of 26 patients with acute promyelocytic leukemia (APL) in the first CR (CR1) or second CR (CR2), who underwent autologous PBSCT (auto-PBSCT) between 1992 and 2008. All patients received all-trans retinoic acid-based induction therapy. After two courses of consolidation chemotherapy, upfront auto-PBSCT was performed in 20 patients in the CR1. Five patients had a high WBC count of more than 10 × 10 9/L (high risk), while 15 patients had a count of less than 10 × 109/L (low risk) at initial presentation. In addition, six patients, who were considered as low-risk patients at presentation, had a relapse after three cycles of consolidation and 2 years of maintenance therapy, but gained the molecular remission after re-induction and consolidation, and underwent auto-PBSCT in the CR2. In 26 recipients, engraftment was rapid and no TRM was documented. All 20 patients autotransplanted in CR1 were still in CR at a median of 133 months (73-193 months), and six patients who underwent auto-PBSCT in CR2 were also still in CR at a median of 41 months (2-187 months) without maintenance therapy. PML/RARα chimeric mRNA was undetectable in PBSC or BM samples examined before auto-PBSCT. Despite a small number of cases studied, our retrospective observations suggest that auto-PBSCT may be an effective treatment option to continue durable CR in the treatment of high-risk APL. We review previous reports and discuss the role of autotransplantation in the treatment of APL patients in CR..
12. A. Numata, T. Miyamoto, Y. Ohno, T. Kamimura, K. Kamezaki, T. Tanimoto, K. Takase, H. Henzan, K. Kato, K. Takenaka, T. Fukuda, N. Harada, K. Nagafuji, T. Teshima, K. Akashi, M. Harada, T. Eto, Long-term outcomes of autologous PBSCT for peripheral T-cell lymphoma
Retrospective analysis of the experience of the Fukuoka BMT group, Bone Marrow Transplantation, 10.1038/bmt.2009.165, 45, 2, 311-316, 2010.02, Peripheral T-cell lymphoma (PTCL) is generally characterized by poor prognosis after conventional chemotherapy compared with aggressive B-cell lymphoma. To elucidate the role of high-dose chemotherapy (HDCT) with auto-SCT, we retrospectively analyzed the outcomes of 39 patients with PTCL who received HDCT and auto-SCT between 1990 and 2005. Eleven patients were histologically typed as angioimmunoblastic, nine as anaplastic large-cell lymphoma, seven as natural killer/T-cell lymphoma and twelve as PTCL unspecified. Clinical conditions at transplantation were complete response (CR) in 27 patients and non-CR in 12 patients. Thirty-two patients received a pre-transplant conditioning regimen (MCEC) comprising ranimustine, carboplatin, etoposide and CY, and seven did other TBI-based regimens. Rapid engraftment awas obtained in all cases, and transplant-related death was not seen. An estimated 5-year OS was 62.1% with a median follow-up of 78 months. The 5-year OS was significantly higher in patients transplanted during complete response than in those during other disease status (71.4% vs 27.3%, P0.046). HDCT supported by auto-SCT may therefore be effective as consolidation in CR for PTCL treatment..
13. Kotaro Shide, Kazuya Shimoda, Kenjiro Kamezaki, Haruko Kakumitsu, Takashi Kumano, Akihiko Numata, Fumihiko Ishikawa, Katsuto Takenaka, Ken Yamamoto, Tadashi Matsuda, Mine Harada, Tyk2 mutation homologous to V617F Jak2 is not found in essential thrombocythaemia, although it induces constitutive signaling and growth factor independence, Leukemia Research, 10.1016/j.leukres.2006.11.003, 31, 8, 1085-1092, 2007.08, A single somatic mutation, V617F, in the pseudokinase domain of the Jak2 is the primary cause of many chronic myeloproliferative diseases. As valine 617 of Jak2 is conserved as valine 678 of Tyk2, we examined the effect of a homologous mutation in Tyk2 (V678F Tyk2) on cell growth. V678F Tyk2 augmented the transcriptional activity of Stat3 and Stat5. The expression of V678F Tyk2 in Ba/F3 cells induced autonomous cell growth and showed hyper-responsiveness to IL-3. Although V678F Tyk2 might cause MPD, no cases of ET patients lacking the V617F Jak2 mutation harbored the Tyk2 mutation..
14. K. Kamezaki, Y. Kikushige, A. Numata, T. Miyamoto, K. Takase, H. Henzan, K. Aoki, K. Kato, A. Nonami, T. Kamimura, F. Arima, K. Takenaka, N. Harada, T. Fukuda, S. Hayashi, Y. Ohno, T. Eto, M. Harada, K. Nagafuji, Rituximab does not compromise the mobilization and engraftment of autologous peripheral blood stem cells in diffuse-large B-cell lymphoma, Bone Marrow Transplantation, 10.1038/sj.bmt.1705649, 39, 9, 523-527, 2007.05, To investigate effects of the preautografting administration of rituximab on the mobilization and engraftment of peripheral blood stem cells (PBSC), we retrospectively analyzed the outcomes of 43 newly diagnosed diffuse-large B-cell lymphoma patients who received CHOP chemotherapy with or without rituximab as a first-line treatment before autologous PBSC transplantation (PBSCT). There was no difference in the number of CD34+ cells among PBSC between the non-rituximab and the rituximab groups. Although B-cells were completely depleted from PBSC in the rituximab group, we found no difference in the expression of CXCR-4, VLA-4 and c-Kit on PBSC, indicating that rituximab did not affect the expression of these adhesion molecules, which might be involved in the mechanism of mobilization. There was no significant difference in the recovery of neutrophils and platelets, transplant-related toxicity and post-transplant complications between the two groups. Despite the short follow-up, there was no significant difference in progression-free survival between the two groups. These results indicated no adverse effect of rituximab on the mobilization and engraftment of PBSC. Larger studies are required to determine the impact of rituximab on the mobilization and function of PBSC as well as whether a survival advantage exists in patients who undergo auto-PBSCT with rituximab..
15. Rie Imamura, Toshihiro Miyamoto, Goichi Yoshimoto, Kenjiro Kamezaki, Fumihiko Ishikawa, Hideho Henzan, Koji Kato, Ken Takase, Akihiko Numata, Koji Nagafuji, Takashi Okamura, Michio Sata, Mine Harada, Shoichi Inaba, Mobilization of human lymphoid progenitors after treatment with granulocyte colony-stimulating factor, Journal of Immunology, 10.4049/jimmunol.175.4.2647, 175, 4, 2647-2654, 2005.08, Hemopoietic stem and progenitor cells ordinarily residing within bone marrow are released into the circulation following G-CSF administration. Such mobilization has a great clinical impact on hemopoietic stem cell transplantation. Underlying mechanisms are incompletely understood, but may involve G-CSF-induced modulation of chemokines, adhesion molecules, and proteolytic enzymes. We studied G-CSF-induced mobilization of CD34 +CD10+CD19-Lin- and CD34 +CD10+CD19+Lin- cells (early B and pro-B cells, respectively). These mobilized lymphoid populations could differentiate only into B/NK cells or B cells equivalent to their marrow counterparts. Mobilized lymphoid progenitors expressed lymphoid- but not myeloid-related genes including the G-CSF receptor gene, and displayed the same pattern of Ig rearrangement status as their bone marrow counterparts. Decreased expression of VLA-4 and CXCR-4 on mobilized lymphoid progenitors as well as multipotent and myeloid progenitors indicated lineage-independent involvement of these molecules in G-CSF-induced mobilization. The results suggest that by acting through multiple trans-acting signals, G-CSF can mobilize not only myeloid-committed populations but a variety of resident marrow cell populations including lymphoid progenitors..
16. Toshihiro Yokoyama, Seiichi Okamura, Yoshinobu Asano, Kenjirou Kamezaki, Akihiko Numata, Haruko Kakumitsu, Koutarou Shide, Hitoshi Nakashima, Taisuke Kanaji, Yuichi Sekine, Yumi Mizuno, Jun Okamura, Tadashi Matsuda, Mine Harada, Yoshiyuki Niho, Kazuya Shimoda, A novel mutation in the juxtamembrane intracellular sequence of the granulocyte colony-stimulating factor (G-CSF) receptor gene in a patient with severe congenital neutropenia augments G-CSF proliferation activity but not through the MAP kinase cascade, International journal of hematology, 10.1532/IJH97.05010, 82, 1, 28-34, 2005.07, We analyzed the structure of the granulocyte colony-stimulating factor (G-CSF) receptor gene in a 6-year-old female patient with severe congenital neutropenia (SCN) who experienced severe recurrent infections since 1 month of age. There is no family history of any similar disease. When the patient was 4 months old, she began receiving treatment with recombinant human G-CSF that resulted in a small increase in the neutrophil count sufficient for the prevention and treatment of bacterial infection. An analysis of complementary DNA for the patient's G-CSF receptor revealed a 3-base pair deletion in the juxtamembrane intracellular sequence. This deletion at the beginning of exon 16 was thought to be caused by alternative splicing; analysis of the DNA revealed a G-to-A point mutation of the final nucleotide of intron 15. To evaluate the functional activity of the G-CSF receptor with this 3-base pair deletion of the juxtamembrane region, we transfected this G-CSF receptor mutant into an interleukin 3-dependent cell line, BAF/3. BAF/3 cells expressing the mutant G-CSF receptor showed augmented proliferation activity in response to G-CSF compared with cells having the wild-type G-CSF receptor. Although the proliferation signal of G-CSF in normal hematopoiesis is transduced through the activation of MAP kinases, this G-CSF receptor mutant showed decreased activation of ERK1/2 in response to G-CSF compared with the wild type, but the transduced signal for Stat3 activation by G-CSF was of the same magnitude as that of the wild-type G-CSF receptor. This result means that the augmented proliferation activity in response to G-CSF that we observed in cells having the G-CSF receptor gene with the 3-base pair deletion is transduced through an intracellular signaling pathway other than MAP kinase. Because SCN patients with a mutation in the G-CSF receptor frequently develop leukemia, this 3-base pair deletion in the juxtamembrane sequence of the G-CSF receptor gene in this patient may be one step in the course of leukemic transformation..
17. Haruko Kakumitsu, Kenjirou Kamezaki, Kazuya Shimoda, Kennosuke Karube, Takashi Haro, Akihiko Numata, Koutarou Shide, Tadashi Matsuda, Kouichi Oshima, Mine Harada, Transgenic mice overexpressing murine thrombopoietin develop myelofibrosis and osteosclerosis, Leukemia Research, 10.1016/j.leukres.2004.12.009, 29, 7, 761-769, 2005.07, Thrombopoietin (TPO) regulates megakaryocytopoiesis and platelet production in vivo and in vitro. Exogenous overexpression of TPO in vivo by viral-mediated gene transfer induced bone marrow (BM) fibrosis and osteosclerosis. On the other hand, transgenic mice (Tg) overexpressing TPO using a liver-specific apolipoprotein E (Apo-E) promoter did not exhibit myelofibrosis or osteosclerosis. These discrepancies in phenotype are not fully understood. Then we have investigated the consequences of long-term in vivo overexpression of TPO in a mouse model. Murine TPO Tg mice driven by the IgH promoter were generated. The number of platelets and neutrophils in peripheral blood, and the number of megakaryocytes and granulocytic immature cells in the BM was elevated, together with the number of progenitor cells for megakaryocyte and myeloid cells. TPO Tg mice demonstrated anemia but the number of progenitor cells for the erythrocyte was increased. TPO Tg mice developed myelofibrosis and osteosclerosis as they aged with extramedullary hematopoiesis in the spleen. As plasma transforming growth factors (TGF)-β1 and osteoprotegerin (OPG) levels were higher in TPO Tg mice than in wild-type mice, the development of myelofibrosis and osteosclerosis depends on local TPO levels in BM and might be due to elevated TGF-β1 and OPG..
18. Akihiko Numata, Kazuya Shimoda, Kenjiro Kamezaki, Takashi Haro, Haruko Kakumitsu, Koutarou Shide, Kouji Kato, Toshihiro Miyamoto, Yoshihiro Yamashita, Yasuo Oshima, Hideaki Nakajima, Atsushi Iwama, Kenichi Aoki, Ken Takase, Hisashi Gondo, Hiroyuki Mano, Mine Harada, Signal transducers and activators of transcription 3 augments the transcriptional activity of CCAAT/enhancer-binding protein α in granulocyte colony-stimulating factor signaling pathway, Journal of Biological Chemistry, 10.1074/jbc.M408442200, 280, 13, 12621-12629, 2005.04, The Janus kinase (Jak)-Stat pathway plays an essential role in cytokine signaling. Granulocyte colony-stimulating factor (G-CSF) promotes granulopoiesis and granulocytic differentiation, and Stat3 is the principle Stat protein activated by G-CSF. Upon treatment with G-CSF, the interleukin-3-dependent cell line 32D clone 3(32Dcl3) differentiates into neutrophils, and 32Dcl3 cells expressing dominant-negative Stat3 (32Dcl3/ DNStat3) proliferate in G-CSF without differentiation. Gene expression profile and quantitative PCR analysis of G-CSF-stimulated cell lines revealed that the expression of C/EBPα was up-regulated by the activation of Stat3. In addition, activated Stat3 bound to CCAAT/enhancer-binding protein (C/EBP)α, leading to the enhancement of the transcription activity of C/EBPα. Conditional expression of C/EBPα in 32Dcl3/DNStat3 cells after G-CSF stimulation abolishes the G-CSF-dependent cell proliferation and induces granulocytic differentiation. Although granulocyte-specific genes, such as the G-CSF receptor, lysozyme M, and neutrophil gelatinase-associated lipocalin precursor (NGAL) are regulated by Stat3, only NGAL was induced by the restoration of C/EBPα after stimulation with G-CSF in 32Dcl3/DNStat3 cells. These results show that one of the major roles of Stat3 in the G-CSF signaling pathway is to augment the function of C/EBPα, which is essential for myeloid differentiation. Additionally, cooperation of C/EBPα with other Stat3-activated proteins are required for the induction of some G-CSF responsive genes including lysozyme M and the G-CSF receptor..
19. Kazuto Takeuchi, Ikuya Sakai, Hirosi Narumi, Masaki Yasukawa, Kensuke Kojima, Yoko Minamoto, Tomoaki Fujisaki, Kazushi Tanimoto, Masamichi Hara, Akihiko Numata, Hisashi Gondo, Masuhiro Takahashi, Nobuharu Fujii, Kozo Masuda, Shigeru Fujita, Expression of SOCS3 mRNA in bone marrow cells from CML patients associated with cytogenetic response to IFN-α, Leukemia Research, 10.1016/j.leukres.2004.06.006, 29, 2, 173-178, 2005.02, Previously, we have demonstrated that constitutive expression of suppressor of cytokine signaling-3 (SOCS3) affects the sensitivity of chronic myelogenous leukemia (CML) cell lines to interferon-α (IFN-α). In the present study, we analyzed the expression of SOCS3 mRNA in bone marrow cells from patients with CML at diagnosis, with the aid of real-time polymerase chain reaction. SOCS3 mRNA expression in bone marrow cells from CML patients who responded well to IFN-α therapy was significantly lower than that in cells from healthy volunteers and patients who were resistant to IFN-α therapy. Methylation of SOCS3 promoter was absent in bone marrow cells from all CML patients examined. These results indicate that the expression of SOCS3 mRNA is inversely associated with the sensitivity to IFN-α both in vitro and in vivo and that differences in SOCS3 mRNA expression are not due to the methylation status of SOCS3 promoters..
20. Kenjirou Kamezaki, Kazuya Shimoda, Akihiko Numata, Takashi Haro, Haruko Kakumitsu, Masumi Yoshie, Masahiro Yamamoto, Kiyoshi Takeda, Tadashi Matsuda, Shizuo Akira, Katsuhiro Ogawa, Mine Harada, Roles of Stat3 and ERK in G-CSF signaling, STEM CELLS, 10.1634/stemcells.2004-0173a, 23, 2, 252-263, 2005.02, G-CSF specifically stimulates the proliferation and differentiation of cells that are committed to the neutrophil-granulocyte lineage. Although Stat3 was thought to be essential for the transduction of G-CSF-induced cell proliferation and differentiation signals, mice deficient for Stat3 in hematopoietic cells show neutrocytosis and infiltration of cells into the digestive tract. The number of progenitor cells in the neutrophil lineage is not changed, and G-CSF-induced proliferation of progenitor cells and prolonged neutrophil survival were observed in Stat3-deficient mice. In hematopoietic cells from Stat3-deficient mice, trace levels of SOCS3, a negative regulator of granulopoiesis, were observed, and SOCS3 expression was not induced by G-CSF stimulation. Stat3-null bone marrow cells displayed a significant activation of extracellular regulated kinase 1 (ERK1)/ERK2 under basal conditions, and the activation of ERK was enhanced and sustained by G-CSF stimulation. Furthermore, the augmented proliferation of Stat3-deficient bone marrow cells in response to G-CSF was dramatically decreased by addition of a MEK1 inhibitor. These results indicate that Stat3 functions as a negative regulator of G-CSF signaling by inducing SOCS3 expression and that ERK activation is the major factor responsible for inducing the proliferation of hematopoietic cells in response to G-CSF..
21. Hisashi Gondo, Daisuke Himeji, Kenjiro Kamezaki, Akihiko Numata, Tetsuya Tanimoto, Ken Takase, Kenichi Aoki, Hideho Henzan, Koji Nagafuji, Toshihiro Miyamoto, Fumihiko Ishikawa, Kazuya Shimoda, Shuichi Inaba, Hiroshi Tsukamoto, Takahiko Horiuchi, Hitoshi Nakashima, Takeshi Otsuka, Koji Kato, Mika Kuroiwa, Masakazu Higuchi, Tsunefumi Shibuya, Tomohiko Kamimura, Kiyotaka Kuzushima, Tatsuya Tsurumi, Yoshinobu Kanda, Mine Harada, Reconstitution of HLA-A*2402 - Restricted cytomegalovirus-specific T-cells following stem cell transplantation, International journal of hematology, 10.1532/IJH97.04109, 80, 5, 441-448, 2004.12, Cytomegalovirus (CMV)-specific immune reconstitution early after stem cell transplantation (SCT) was evaluated prospectively by detecting CD8+ T-cells, which recognize the peptide QYDPVAALF in the context of HLA-A*2402. Fifteen allogeneic SCT recipients were included in the study. All recipients and donors were seropositive for CMV and had the HLA-A*2402 allele. CMV-specific T-cells were detected as early as 1 month after transplantation, and their numbers increased to peak levels 2 to 5 months after transplantation. The numbers of CMV-specific T-cells in patients who developed grade II to IV acute graft-versus-host disease (GVHD) and received corticosteroids for acute GVHD were low in the early period after allogeneic SCT. There was a trend toward earlier reconstitution of CMV-specific CD8+ T-cells in allogeneic peripheral blood SCT (PBSCT) patients than in allogeneic bone marrow transplan tation patients. The contribution of T-cells in the graft to the recovery of CMV-specific immune responses was also suggested by the finding that the reconstitution of CMV-specific CD8+ T-cells was delayed in CD34-selected autologous PBSCT compared with unpurged autologous PBSCT. The reconstitution of CMV-specific CD8+ T-cells was delayed in patients with CMV disease or recurrent CMV reactivation. These observations suggest that the detection of CMV-specific T-cells with an HLA-peptide tetramer is useful to assess immune reconstitution against CMV and to identify patients at risk for CMV disease or recurrent CMV reactivation after SCT..
22. Kenjirou Kamezaki, Kazuya Shimoda, Akihiko Numata, Tadashi Matsuda, Kei Ichi Nakayama, Mine Harada, The role of Tyk2, Stat1 and Stat4 in LPS-induced endotoxin signals, International immunology, 10.1093/intimm/dxh118, 16, 8, 1173-1179, 2004.08, Mice lacking Tyk2, Stat1 or Stat4, which are members of the Jak-Stat signaling cascade, were resistant to LPS-induced endotoxin shock. Interestingly, Tyk2-deficient mice had higher resistance to LPS challenge than mice lacking either Stat1 or Stat4. The activation of MAPK and NF-κB by LPS, and the production of TNF-α and IL-12 after LPS injection, were not abrogated by the absence of Tyk2, Stat1 or Stat4 In Stat1-deficient mice, the induction of IFN-β by LPS in macrophages was severely reduced, although the serum level of IFN-γ was elevated after LPS injection. In contrast, in Stat-4 deficient mice, the induction of IFN-β by LPS was normal, but the serum level of IFN-γ remained low after LPS injection. Interestingly, the induction of both IFN-β and IFN-γ by LPS was severely reduced in Tyk2-deficient mice. Therefore, Stat1 and Stat4 independently play substantial roles in the susceptibility to LPS. Tyk2 is essential for LPS-induced endotoxin shock, and this signaling pathway is transduced by the activation of Stat1 and Stat4..
23. Takashi Haro, Kazuya Shimoda, Haruko Kakumitsu, Kenjirou Kamezaki, Akihiko Numata, Fumihiko Ishikawa, Yuichi Sekine, Ryuta Muromoto, Tadashi Matsuda, Mine Harada, Tyrosine kinase 2 interacts with and phosphorylates receptor for activated C kinase-1, a WD motif-containing protein, Journal of Immunology, 10.4049/jimmunol.173.2.1151, 173, 2, 1151-1157, 2004.07, Receptor for activated C kinase (Rack)-1 is a protein kinase C-interacting protein, and contains a WD repeat but has no enzymatic activity. In addition to protein kinase C, Rack-1 also binds to Src, phospholipase Cγ, and ras-GTPase-activating proteins. Thus, Rack-1 is thought to function as a scaffold protein that recruits specific signaling elements. In a cytokine signaling cascade, Rack-1 has been reported to interact with the IFN-αβ receptor and Stat1. In addition, we show here that Rack-1 associates with a member of Jak, tyrosine kinase 2 (Tyk2). Rack-1 interacts weakly with the kinase domain and interacts strongly with the pseudokinase domain of Tyk2. Rack-1 associates with Tyk2 via two regions, one in the N terminus and one in the middle portion (aa 138-203) of Rack-1. Jak activation causes the phosphorylation of tyrosine 194 on Rack-1. After phosphorylation, Rack-1 is translocated toward the perinuclear region. In addition to functioning as a scaffolding protein, these results raise the possibility that Rack-1 functions as a signaling molecule in cytokine signaling cascades..
24. Tetsuya E. Tanimoto, Takuhiro Yamaguchi, Yuji Tanaka, Akiko Saito, Kinuko Tajima, Takahiro Karasuno, Masanobu Kasai, Kenji Kishi, Takehiko Mori, Nobuo Maseki, Satoko Morishima, Shigesaburo Miyakoshi, Masaharu Kasai, Yuju Ohno, Sung Won Kim, Akihiko Numata, Masahiro Kami, Yoichi Takaue, Shinichiro Mori, Mine Harada, Comparative analysis of clinical outcomes after allogeneic bone marrow transplantation versus peripheral blood stem cell transplantation from a related donor in Japanese patients, British Journal of Haematology, 10.1111/j.1365-2141.2004.04943.x, 125, 4, 480-493, 2004.05, A reduced incidence of graft versus host disease (GvHD) has been documented among Japanese allogeneic bone marrow transplantation (BMT) patients, as the Japanese are genetically more homogeneous than western populations. To clarify whether this ethnic difference affects the results of allogeneic peripheral blood stem cell transplantation (PBSCT), we conducted a nationwide survey to compare clinical outcomes of allogeneic PBSCT (n = 214) and BMT (n = 295) from a human leucocyte antigen-identical-related donor in Japanese patients. The cumulative incidence of grades II-IV acute GvHD was 37.4% for PBSCT and 32.0% for BMT. The cumulative incidence of extensive chronic GvHD at 1 year was significantly higher after PBSCT than BMT (42% vs. 27%; P < 0.01). The organ involvement patterns of GvHD were different between the two groups. By multivariate analyses, the incidence of chronic GvHD was significantly increased in PBSCT, whereas the stem cell source did not affect the incidence of acute GvHD, transplant-related mortality, relapse or survival. We concluded that Japanese PBSCT patients have an increased risk of chronic GvHD compared with BMT patients, but the incidence of acute GvHD was still lower than in western populations. Thus, the choice of haematopoietic stem cell source should be considered based on data for individual ethnic populations..
25. Kenichi Aoki, Kazuya Shimoda, Kenji Oritani, Tadashi Matsuda, Kenjirou Kamezaki, Ryuta Muromoto, Akihiko Numata, Sadafumi Tamiya, Takashi Haro, Fumihiko Ishikawa, Ken Takase, Tetsuya Yamamoto, Taro Yumioka, Toshihiro Miyamoto, Koji Nagafuji, Hisashi Gondo, Seiho Nagafuchi, Kei Ichi Nakayama, Mine Harada, Limitin, an interferon-like cytokine, transduces inhibitory signals on B-cell growth through activation of Tyk2, but not Stat1, followed by induction and nuclear translocation of Daxx, Experimental Hematology, 10.1016/j.exphem.2003.08.011, 31, 12, 1317-1322, 2003.12, Objective. Limitin, an interferon-like cytokine, suppresses B lymphopoiesis through ligation of the interferon-α/β (IFN-α/β) receptor. The aim of this study was to examine the intracellular signal transduction pathways activated by limitin. Materials and Methods. The effects of limitin on cell growth, the activation of Jak kinase and Stat proteins, and the induction of interferon regulatory factor-1 (IRF-1) and Daxx were examined using the mouse pre-B-cell line 18.81, wild-type, and Tyk2-deficient mouse bone marrow cells. In addition, the change of localization of the Daxx protein after limitin treatment in wild-type and Tyk2-deficient mice was examined. Results. Limitin phosphorylates Tyk2, Jak1, Stat1, and Stat2 and rapidly induces IRF-1 mRNA production. Phosphorylation of Stat1 by limitin is partially dependent on Tyk2. Suppression of B-cell growth by limitin, however, is severely impaired in the absence of Tyk2, whereas it is unaffected by the absence of Stat1. Limitin also induces the expression and nuclear translocation of Daxx, which is essential for IFN-α-induced inhibition of B-lymphocyte development. The absence of Tyk2 abrogates this induction of Daxx expression and nuclear translocation. Conclusions. Limitin suppresses B-cell growth through activation of Tyk2, resulting in the up-regulation and nuclear translocation of Daxx. This limitin-mediated signaling pathway does not require Stat1..
26. Kenjirou Kamezaki, Kazuya Shimoda, Akihiko Numata, Kenichi Aoki, Kouji Kato, Ken Takase, Hideaki Nakajima, Kenji Ihara, Takashi Haro, Fumihiko Ishikawa, Rie Imamura, Toshihiro Miyamoto, Koji Nagafuji, Hisashi Gondo, Toshiro Hara, Mine Harada, The lipocalin 24p3, which is an essential molecule in IL-3 withdrawal-induced apoptosis, is not involved in the G-CSF withdrawal-induced apoptosis, European Journal of Haematology, 10.1046/j.0902-4441.2003.00160.x, 71, 6, 412-417, 2003.12, Many hematopoietic cells undergo apoptosis when deprived of specific cytokines. Lipocalin 24p3, reported to be induced in hematopoietic cells by interleukin 3 (IL-3) depletion, induces hematopoietic cell apoptosis despite the presence of IL-3. As granulocyte colony stimulating factor (G-CSF) depletion also induces the apoptosis of G-CSF-dependent cell line cells, we examined the effect of 24p3 on the apoptotic function induced by G-CSF depletion. 24p3 was induced by the depletion of IL-3, but not G-CSF, in cytokine-dependent cell lines. Although 24p3 suppressed growth induced by IL-3, it did not influence G-CSF-dependent cell growth. These observations show that 24p3 is not involved in the G-CSF withdrawal-induced apoptosis, although it is essential in IL-3 withdrawal-induced apoptosis..
27. Kouji Kato, Kenjirou Kamezaki, Kazuya Shimoda, Akihiko Numata, Takashi Haro, Kenichi Aoki, Fumihiko Ishikawa, Ken Takase, Hiroshi Ariyama, Tadashi Matsuda, Toshihiro Miyamoto, Koji Nagafuji, Hisashi Gondo, Kei Ichi Nakayama, Mine Harada, Intracellular signal transduction of interferon on the suppression of haematopoietic progenitor cell growth, British Journal of Haematology, 10.1046/j.1365-2141.2003.04650.x, 123, 3, 528-535, 2003.11, Interferon (IFN)-α and IFN-γ suppress the growth of haematopoietic progenitor cells. IFN-α activates Janus kinase-1 (Jak1) and Tyrosine kinase-2 (Tyk2), followed by the phosphorylation of the signal transducers and activators of transcription, Stat1 and Stat2. IFN-γ activates Jak1 and Jak2, followed by the activation of Stat1. Activated Stats bind the promoter regions of IFN-inducible genes. We evaluated the role of Tyk2 and Stat1 in the IFN-mediated inhibition of haematopoietic progenitor cell growth. While IFN-α (1000 U/ml) suppressed the number of granulocyte-macrophage colony-forming units (CFU-GM) or erythroid burst-forming units (BFU-E) from wild-type mouse bone marrow cells, this suppression was partially inhibited by a deficiency in Tyk2 and completely inhibited by a deficiency in Stat1. High levels of IFN-α (10 000 U/ml) suppressed the CFU-GM or BFU-E obtained from Stat1-deficient mice, but did not suppress this growth in cells from Tyk2-deficient mice, Stat1 was phosphorylated by IFN-α in Tyk2-deficient cells, although the level of phosphorylation was weaker than that observed in wild type mice. Thus, the inhibitory signal on haematopoietic progenitor cells mediated by IFN-α may be transduced by two signalling pathways, one regulated by Tyk2 and the other dependent on Stat1. IFN-γ also suppressed the number of CFU-GM or BFU-E, and this pathway was mediated by IFN-γ in a Stat1-dependent manner, independently of Tyk2..
28. Kazuya Shimoda, Kenjirou Kamesaki, Akihiko Numata, Kenichi Aoki, Tadashi Matsuda, Kenji Oritani, Sadafumi Tamiya, Kouji Kato, Ken Takase, Rie Imamura, Tetsuya Yamamoto, Toshihiro Miyamoto, Koji Nagafuji, Hisashi Gondo, Seiho Nagafuchi, Kei Ichi Nakayama, Mine Harada, Cutting edge
Tyk2 is required for the induction and nuclear translocation of Daxx which regulates IFN-α-induced suppression of B lymphocyte formation, Journal of Immunology, 169, 9, 4707-4711, 2002.11, IFN-α inhibits B lymphocyte development, and the nuclear protein Daxx has been reported to be essential for this biological activity. We show in this study that IFN-α inhibits the clonal proliferation of B lymphocyte progenitors in response to IL-7 in wild-type, but not in tyk2-deficient, mice. In addition, the IFN-α-induced up-regulation and nuclear translocation of Daxx are completely abrogated in the absence of tyk2. Therefore, tyk2 is directly involved in IFN-α signaling for the induction and translocation of Daxx, which may result in B lymphocyte growth arrest and/or apoptosis..
29. K. Yakushiji, H. Gondo, Kenjiro Kamezaki, K. Shigematsu, S. Hayashi, M. Kuroiwa, S. Taniguchi, Y. Ohno, K. Takase, Akihiko Numata, K. Aoki, Koji Kato, K. Nagafuji, K. Shimoda, T. Okamura, N. Kinukawa, N. Kasuga, M. Sata, M. Harada, Monitoring of cytomegalovirus reactivation after allogeneic stem cell transplantation
Comparison of an antigenemia assay and quantitative real-time polymerase chain reaction, Bone Marrow Transplantation, 10.1038/sj/bmt/1703513, 29, 7, 599-606, 2002.06, Cytomegalovirus (CMV) antigenemia and quantitative real-time polymerase chain reaction (PCR) were compared for monitoring of CMV reactivation after allogeneic stem cell transplantation. The number of CMV antigen-positive cells by the antigenemia assay and the level of CMV DNA by real-time PCR correlated well. The sensitivity and specificity of the antigenemia assay was 55.4% and 95.5%, respectively, using real-time PCR as the reference standard. The probability of positive antigenemia at day 100 was 76.5%, with a median of first detection at day 37 in 51 patients, compared with a positive PCR of 84.3% and day 33, respectively. When HLA-identical sibling donor transplant recipients and other donor transplant recipients were analyzed separately, there was no difference between the two tests. However, temporal patterns of first detection of CMV antigen-positive cells and CMV DNA differed between HLA-identical and alternative recipients; patients without CMV (29%) or with sporadic positive PCR results (14%) were more common in HLA-identical sibling transplants, wereeas patients with simultaneous antigenemia and positive PCR occurred more in alternative transplants (48%). Two of 51 patients (4%) developed CMV colitis despite antigenemia-guided prophylaxis, but both were successfully treated with ganciclovir. Although PCR is more sensitive than antigenemia, both tests are useful in the early detection of CMV after allogeneic stem cell transplantation..