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S Hibi

Publications and source records attributed to S Hibi.

At least 55 records · Page 3Linked to original sources
PubMed2000

Outcome of clonal hemophagocytic lymphohistiocytosis: analysis of 32 cases.

We studied the impact of clonality, determined by analysis of Epstein-Barr virus genome termini, T-cell receptor genes and clonal chromosomal abnormality, on the clinical outcome in 32 patients with hemophagocytic lymphohistiocytosis (HLH). Of the cases studied, 23 cases were EBV-clonal, 15 cases were TCR-clonal and 7 cases were cytogenetically clonal. Thirty patients were treated with immuno-chemotherapy and/or multiagents' chemotherapy and 4 received bone marrow transplantation. All 7 cases, in which cytogenetically abnormal clones were identified, were fatal (3-year survival by Kaplan-Meier analysis; 14%, 95%CI: 0-40%). None of these 7 cases received bone marrow transplantation. On the other hand, the 3-year survival of 23 clonal EBV-positive HLH cases including 4 cytogenetically abnormal cases was 64 % (95%CI: 42-84%), while that of 15 TCR-clonal cases was 53% (95%CI: 26-78%). Our observations suggest that cytogenetically abnormal cases are at extremely high risk, requiring intensive immuno-chemotherapy followed by prompt and timely allogeneic bone marrow transplantation.

Adolescent↗
PubMed2000

Management of severe neutropenia with cyclosporin during initial treatment of Epstein-Barr virus-related hemophagocytic lymphohistiocytosis.

Severe neutropenia (absolute neutrophil count <500/gl) is probably due to the combined effects of dysregulated cytokine production and chemotherapeutic agents, and is one of the risk factors in the initial treatment of patients with Epstein-Barr virus-related hemophagocytic lymphohistiocytosis (EBV-HLH). We report here 9 cases of neutropenic HLH, of which 8 were treated with cyclosporin (CSA, 2-6 mg/kg/day; continuous infusion, or 6 mg/kg/day; per os, for periods ranging from 9 days to >8 weeks) in the initial neutropenic phase during induction treatment using corticosteroids and etoposide. Five of the 6 cases, in which CSA treatment was started early (before the second week of induction), survived the critical period with recovery of neutrophil counts within a week. The remaining 3 cases, in which CSA was introduced later or not at all, died of infection. Based on these results, we recommend a prompt short-term CSA infusion during neutropenic episodes in the most common treatment regimen of etoposide and corticosteroids in patients with HLH. Improved neutrophil recovery as a result of CSA treatment makes it possible to continue immunochemotherapy safely and obtain improved patient outcomes.

Adolescent↗
PubMed2000

Bone marrow changes mimicking myelodysplasia in patients with hemophagocytic lymphohistiocytosis.

In hemophagocytic lymphohistiocytosis (HLH), cytokine-induced pancytopenia is a common finding and is associated with hypoplastic and hypocellular bone marrow and abundant hemophagocytosis. To date, neutrophil nuclear segmentation abnormalities have not been clarified in HLH patients. We report a study of bone marrow from 6 cases of HLH that showed abnormal granulocytes, dyserythropoietic changes, and micromegakaryocytes mimicking the findings in myelodysplasia at the onset of disease. Pelger-Huët anomalies were particularly noted in all cases. The increased levels of cytokines in these cases may have caused cellular damage leading to the morphological changes in the bone marrow of these HLH patients. The impact of these findings on pathophysiology and prognosis in HLH patients remains to be determined.

Adolescent↗
PubMed1999

Clonal expansion of alphabeta-T lymphocytes with inverted Jbeta1 bias in familial hemophagocytic lymphohistiocytosis.

Familial hemophagocytic lymphohistiocytosis (FHL) is a rare but fatal disease in infancy. There are no previous reports on the clonality of T cells in FHL patients. We analyzed here the clonality of alphabeta-T cells in 5 FHL patients using an inverse reverse transcriptase-polymerase chain reaction (RT-PCR) of the T-cell receptor variable region gene (TCR V), a joining region gene of the beta chain (Jbeta)-PCR, a single-strand conformation polymorphism (SSCP), and sequence analysis. A high frequency (15%) of Vbeta and Valpha families was observed in 3 of 5 and 4 of 4 patients examined, respectively. In 19 Vbeta repertoires, including all highly frequent Vbeta, the Jbeta-PCR analysis showed restricted usage of the Jbeta family, indicating a marked bias to Jbeta1 subsets (the mean rate of Jbeta1:Jbeta2 was 87:13 in 65% of the alphabeta-T cells) in widespread alphabeta-T cells (in all patients but 1). In all patients, the clonality of specific Vbeta-Jbeta fragment expanded was confirmed by SSCP and sequence analysis. These results suggest that the existence of clonal expansion and restricted Jbeta1 usage of T cells in FHL is genetically associated with the pathogenesis and the immunodysfunction of the disease. These results help to explain some of the abnormal functional behaviors of T cells in FHL and raise new questions regarding the mechanisms responsible for the restricted clonal diversity.

Amino Acid Sequence↗
PubMed1999

Effective control of Epstein-Barr virus-related hemophagocytic lymphohistiocytosis with immunochemotherapy. Histiocyte Society.

The familial form of hemophagocytic lymphohistiocytosis (HLH) is a lethal disorder. Although the prognosis for Epstein-Barr virus-associated HLH (EBV-HLH) remains uncertain, numerous reports indicate that it can also be fatal in a substantial proportion of cases. We therefore assessed the potential of immunochemotherapy with a core combination of steroids and etoposide to control EBV-HLH in 17 infants and children who met stringent diagnostic criteria for this reactive disorder of the mononuclear phagocyte system. Treatment of life-threatening emergencies was left to the discretion of participating investigators and typically included either intravenous Ig or cyclosporin A (CSA). Five patients (29%) entered complete remission during the induction phase (1 to 2 months), whereas 10 others (57%) required additional treatment to achieve this status. In 2 cases, immunochemotherapy was ineffective, prompting allogeneic bone marrow transplantation. Severe but reversible myelosuppression was a common finding; adverse late sequelae were limited to epileptic activity in one child and chronic EBV infection in 2 others. Fourteen of the 17 patients treated with immunochemotherapy have maintained their complete responses for 4+ to 39+ months (median, 15+ months), suggesting a low probability of disease recurrence. These results provide a new perspective on EBV-HLH, showing effective control (and perhaps cure) of the majority of EBV-HLH cases without bone marrow transplantation, using steroids and etoposide, with or without immunomodulatory agents.

Child↗
PubMed1999

Clonal dissemination of T-lymphocytes in scid mice from familial hemophagocytic lymphohistiocytosis.

BACKGROUND: Although familial hemophagocytic lymphohistiocytosis (FHL) has been considered a disorder of T-cell dysfunction, there is no evidence of the clonal origin of T-cells in this disease. PROCEDURE: We engrafted mononuclear cells (MNCs) from five FHL patients into scid mice and examined the infiltration of human cells in mouse organs. The characterization of human cells that infiltrated in the mouse organs was then performed. RESULTS: A diffuse infiltration of human lymphoid cells was detected in scid mice treated with 1 x 10(6) MNCs from one of the five patients. These cells were positive for HLA-DR and CD3, but negative for CD4, CD8, CD20, and CD68, suggesting the infiltration of double negative (DN) T-cells. The MNCs from the other four patients induced murine lymphoma-like disease; T-cell lymphoma in one and lymphoma of unknown origin in three. The characterization of these human DN T-cells was performed. The analysis of the Vbeta repertoire showed no preferential usage of the Vbeta family in MNCs, while the dominant expression of Vbeta13 was detected in T-cells infiltrating in the spleen and lung. A Jbeta analysis showed the restricted usage of Jbeta1.2 for Vbeta13 in these cells, and the clonality of Vbeta13-Jbeta1.2 fragment was confirmed by a single-strand confirmation polymorphism analysis. The analysis of the Valpha repertoire showed that Valpha24 was exclusively used in these DN T-cells, but no usage of JalphaQ for Valpha24 was observed. CONCLUSIONS: A clonal expansion of T-cells was induced in scid mice by the engraftment of MNCs from an FHL patient. The infiltration of DN alphabeta T-cells bearing invariant Valpha24 T-cell receptor in mouse organs may provide a useful clue to the pathogenesis of FHL. In the patients whose MNCs induced murine lymphoma-like disease, some cytokines or unknown factors that stimulate the growth and the tumorigenicity of murine lymphocytes might be produced by the MNCs engrafted in scid mice. Further study is needed to confirm the validity of our experimental approach and the findings observed in scid mice by using more FHL samples.

Animals↗
PubMed1999

Allogeneic hematopoietic stem cell transplantation for patients with hemophagocytic syndrome (HPS) in Japan.

Seventeen cases (age at onset, 1 month to 18 years; M/F, 9/8) of hemophagocytic syndrome which received allogeneic hematopoietic stem cell transplantation (SCT) in Japan during the period 1988-1998 are reported. The patients consisted of six familial inheritance-proven erythrophagocytic lymphohistiocytosis (FEL), five familial inheritance-unknown and infective agents-unknown HLH (of which two were highly likely to have been FEL with characteristic CNS signs), and six aggressive Epstein-Barr virus (EBV)-related HLH (of which two were natural killer cell-type large granular leukemia/lymphoma-associated hemophagocytic syndrome, EBV-NK-LGLL-HPS). All cases were treated intensively with immuno-chemotherapy, or with chemotherapy before SCT. As sources of SCT, 12 cases received bone marrow cells (sibling six, father one, URD five), two cord blood, two purified CD34-positive cells, and one PBSC. SCTs were successful in all 17 cases, apart from one receiving CD34-positive SCT. Following SCT, four patients relapsed and five died with a median follow-up of 23 months. Among the relapsed cases, the two EBV-NK-LGLL-HPS previously published as successfully transplanted were included. Among the fatal cases, three patients died from relapsed active disease and the remaining two from fatal post-SCT EBV-positive T cell lymphoma and extensive chronic GVHD, respectively. As of the end of September 1998, 10 patients are alive without disease for 3.5 months to 147 months, while two post-SCT patients are still having therapy for residual/recurrent disease. The Kaplan-Meier analysis showed a 2-year event-free survival after SCT as 54.0+/-13.0%.

Adolescent↗
PubMed1999

WASP is involved in proliferation and differentiation of human haemopoietic progenitors in vitro.

The Wiskott-Aldrich syndrome (WAS) is an X-linked recessive disorder characterized by thrombocytopenia, immunodeficiency and eczema. X-linked thrombocytopenia (XLT) is a mild form of WAS with isolated thrombocytopenia. Both phenotypes are caused by mutation of the Wiskott-Aldrich syndrome protein (WASP) gene. In this study we investigated the role of WASP in the differentiation of CD34-positive (CD34+) cells isolated from the bone marrow of patients with WAS (n = 5) or with XLT (n = 4). Megakaryocyte colony formation was significantly decreased in patients with WAS when compared with normal controls. The formation of granulocyte-macrophage colonies and erythroid bursts were also decreased in WAS patinets. In contrast, in XLT patients, formation of all these colonies was normal. However, in vitro proplatelet formation of megakaryocytes induced by thrombopoietin was markedly decreased in both XLT and WAS. Electron microscopic examination revealed that megakaryocytes obtained from WAS or XLT patients grown in vitro had abnormal morphologic features, which seemed to be caused by defective actin cytoskeletal organization, including labyrinth-like structures of the demarcation membrane system and deviated distribution of the alpha-granules and demarcation membrane system. These observations indicate that WASP is involved in the proliferation and differentiation of CD34+ haemopoietic progenitor cells probably by its participation in signal transduction and in the regulation of the cytoskeleton.

Blood Platelets↗
PubMed1999

Hemophagocytosis by leukemic blasts in a case of acute megakaryoblastic leukemia with t(16;21)(p11;q22).

We report the case of a 2-year-3-month-old boy with acute megakaryoblastic leukemia showing hemophagocytosis by leukemic blasts. The chromosome analysis of his bone marrow revealed t(16;21)(p11;q22). In addition to the present case, we found 4 other acute myeloid leukemia (AML) cases associated with hemophagocytosis and t(16;21)(p11;q22) in the literature, of which 3 were megakaryoblastic. Although the syndrome of AML with FAB-M4/5 morphology, t(8;16)(p11;p13), and erythrophagocytosis is well known, leukemic blasts of FAB-M7 morphology showing t(16;21)(p11;q22) may be underscored for their phagocytic activity.

Child, Preschool↗
PubMed1999

[Successful immunosuppressive therapy for a patient with hypoplastic myelodysplastic syndrome].

We encountered a patient with hypoplastic myelodysplastic syndrome (MDS) who responded to immunosuppressive therapy including antithymocyte globulin and cyclosporin A (CsA). A 13-year-old girl was referred to our hospital because of pancytopenia. Bone marrow smears disclosed extreme hypocellularity without cellular atypism. A diagnosis of aplastic anemia was made, and immunosuppressive therapy consisting of ATG, CsA, granulocytecolony-stimulating factor (G-CSF), methylprednisolone, and danazol was started. A month later dysplastic cells appeared in the bone marrow. The karyotype of pretreatment bone marrow cells was 46, XX, del (13) (q12; q14). Therefore, the final diagnosis was hypoplastic MDS. CsA and danazol were continued. The patient became transfusion-independent 1 month later and dysplastic cells disappeared from bone marrow 3 months later. The chromosomal abnormality also became undetectable 6 months after the initiation of treatment. These findings indicated that immunosuppressive therapy is beneficial for patients with hypoplastic MDS.

Adolescent↗
PubMed1999

[Relapse of acute lymphoblastic leukemia as a retro-orbital mass].

A 16-year-old girl who had been treated for B-precursor acute lymphoblastic leukemia (ALL) presented with a mass in the left orbit as an isolated relapse. Five years earlier, she had undergone chemotherapy that promptly resulted in a complete remission. For prophylaxis of central nervons system leukemia, the patient received cranial radiotherapy (18 Gy) with shielding of the orbit and 15 cycles of intrathecal MTX and prednisolone. Cerebrospinal fluid analysis did not detect infiltration during the treatment course. Exophthalmos of the eft eye and hyperemia of the conjuctiva developed 15 months after therapy. Computed tomography showed a retro-orbital mass behind the left eye. Though bone marrow aspiration was negative, biopsy specimens from the mass disclosed the infiltration of CD10-positive leukemic blasts. After 8 courses of chemotherapy, 5 cycles of intrathecal MTX, and orbital irradiation (24 Gy), the mass disappeared. All relapse as an isolated retro-orbital mass is very rare, and only 3 cases have been reported to date.

Adolescent↗
PubMed1998

Syntheses and structure-activity relationships of novel retinoid X receptor agonists.

As part of our studies to develop novel retinoids with increased affinity and selectivity for the retinoid X receptor (RXR) subfamily, we have designed and synthesized a series of (E,E,E)-7-(1,2,3, 4-tetrahydroquinolin-6-yl)-7-alkyl-6-fluoro-3-methylhepta-2, 4, 6-trienoic acid derivatives. These tetrahydroquinolines, generated by introducing a polar N atom into the hydrophobic part of the retinoid skeleton, showed high binding affinity to RXRs. Addition of fluorine at the 6-position of the 2,4,6-trienoic acid moiety afforded compounds which elicit potent and selective transactivation of the RXRs. Compound 14b (ER-35794), which possesses an ethyl substituent at the 7-position and fluorine at the 6-position of the triene moiety, is one of the most potent and selective RXR agonists reported to date.

Animals↗
PubMed1998

Biomarker and morphological characteristics of Epstein-Barr virus-related hemophagocytic lymphohistiocytosis.

BACKGROUND: Viruses may induce primary as well as secondary hemophagocytic lymphohistiocytosis (HLH), but it may not be possible to discriminate between these two in patients with a negative family history. Among these HLH cases, fulminant and fatal virus-associated hemophagocytic syndrome (VAHS) occurs mostly in relation to Epstein-Barr virus (EBV) infection. Although the immunological characteristics of EB-VAHS were previously reported, data on non-EB-VAHS were sporadic and fragmentary. This study has compared the clearly distinguishable groups of EBV-positive vs. EBV-negative HLH cases. PROCEDURE: Among 26 patients with EBV-related HLH and 12 patients with non-EBV HLH, peripheral blood mononuclear cell (PBMC) subsets and serum concentrations of cytokines at the active phase of the disease were compared. Blood and bone marrow smears were also compared. RESULTS AND CONCLUSIONS: The frequency of the CD3+HLADR+ subset in PBMC (median 34.3% vs. 4.8%), of serum concentrations of interferon (IFN)-gamma (median 105 U/ml vs. 2.4 U/ml), and of soluble interleukin-2-receptor (sIL-2R) (median 14,700 U/ml vs. 3,412 U/ml) were significantly different between these two groups. Morphological characteristics were noted for EBV-related HLH cases. Mortality also differed between these two groups, 9/26 vs. 0/12 (P = 0.05). Data indicate pronounced immunological imbalance and poor prognosis in EBV-related HLH cases. These parameters could be useful for determining an EBV involvement as well as risk factors in the early care and treatment of HLH patients.

Adolescent↗
PubMed1998

Donor lymphocyte infusion at unstable mixed chimerism in an allogeneic BMT recipient for chronic granulomatous disease.

We report a 14-year-old boy who had successfully received allogeneic BMT for chronic granulomatous disease and 3 years later was treated with donor lymphocyte infusion (DLI, 3.3 x 10(8) cells/kg) at unstable mixed chimerism in association with reduced neutrophil function. Following DLI, the patient developed transient acute hepatic GVHD, which was confirmed by liver biopsy and was manageable with cyclosporin A and prednisolone. The patient eventually attained complete chimerism with improved neutrophil function. At the time of writing (2.5 years from the DLI), the patient is doing well, free from infectious episodes and chronic GVHD. Our experience suggests that DLI could be a safe and effective strategy for dissolution of unstable mixed chimerism in BMT recipients for inherited disorders.

Adolescent↗
PubMed1998

[Post-transplant EBV-associated lymphoproliferative disorders--report of two cases].

We report two cases of Epstein-Barr virus (EBV)-associated lymphoproliferative disorders (LPD) after allogenic bone marrow transplantation which were conditioned with regimens including antithymocyte globulin (ATG). The first case was a 31 year-old man which severe aplastic anemia who was transplanted from HLA-matched unrelated donor conditioned with total lymphoid irradiation (TLI)/ cyclophosphamide/ATG and prophylactic administration of ganciclovir Grade I acute GVHD improved in response to cyclosporine (CsA). LPD as a polyclonal epipharyngeal mass developed at day +53 and spontaneously regressed along with the withdrawal of CsA. Second case was a 11 year-old boy with acute myelomonocytic leukemia (FAB:M4E). He was transplanted from HLA B locus mismatched mother conditioned with total body irradiation (TBI)/busulfan/L-PAM/ATG. He showed grade IV acute GVHD, which was controlled by steroids and FK-506. LPD as a monoclonal intestinal lymphoma was diagnosed at day +82, and he was unsuccessfully treated with ganciclovir, acyclovir, chemotherapy and transfusions of EBV-specific cytotoxic lymphocytes in addition to discontinuation of immunosuppressants, and died at day +18 due to sepsis and multiple cerebral infarction. Early detection and introduction of appropriate treatment for post bone marrow transplantation LPD is necessary.

Adult↗