Hiroto Sakoda

Establishment and characterization of a transplantable erythroblastic leukemia in C3H mice

A disease with the characteristics of an erythroblastic leukemia was induced by X-ray irradiation of 300 Rads in C3H mice. The leukemia is transplantable in syngeneic mice by i.v. injection of the spleen cells. The mice show almost pure erythroid cells of various differentiation stages in peripheral blood. The number of total nucleated cells in the peripheral blood increased, but hematocrit and platelet number decreased. Reverse transcriptase activities were measured in spleen and liver of the mice and the data suggested that the leukemia was not induced by retrovirus infection. This leukemia is distinguishable, in this respect, from diseases reported by Friend or Rauscher. The leukemia will offer a good animal model for the studies on non-viral leukemogenesis and disorders of erythropoiesis.

Stromal Cell-dependent Growth of Leukemic Cells from Murine Erythroblastic Leukemia

Transplantable erythroblastic leukemia was induced by 300‐rad irradiation of C3H mice. Conditions for in vitro growth of the leukemic cells were studied. None of interleukin‐3, granulocyte/macrophage colony‐stimulating factor and erythropoietin could support the growth of the cells in vitro. In contrast, the leukemic cells grew into a stroma‐dependent cell line, ELM‐D, in close contact with the stromal cell layer of 900‐rad‐irradiated long‐term bone marrow culture. A stroma‐independent cell line, termed ELM‐I‐1, was further established from the non‐adherent population in the co‐culture of the leukemic cells, ELM‐D, with stromal cells. Reverse transcriptase activity was not detectable in ELM‐D or ELM‐I‐1 cells. Studies on binding and cross‐linking of 125I‐erythropoietin showed that ELM‐I‐1 cells had erythropoietin receptors, and two major radiolabeled protein products with molecular weights of 120 kDa and 140 kDa were detected on sodium dodecyl sulfate/polyacrylamide gel electrophoresis under reducing conditions.

Abrupt evolution of Philadelphia chromosome‐positive acute myeloid leukemia in myelodysplastic syndrome

Myelodysplastic syndrome (MDS) is a clonal disorder arising from an alteration in multipotent stem cells, which lose the ability of normal proliferation and differentiation. Disease progression occurs in approximately 30% MDS cases. Specific chromosomal alterations seem responsible for each step in the evolution of acute myeloid leukemia (AML). Multiple genetic aberrations occur during the clonal evolution of MDS; however, few studies report the presence of the Philadelphia (Ph) chromosome. We report a rare case of Ph‐positive AML, which evolved during the course of low‐risk MDS. The patient, a 76‐year‐old man with mild leukocytopenia, was diagnosed with MDS, refractory neutropenia (RN). After 1.5 yr, his peripheral blood and bone marrow were suddenly occupied by immature basophils and myeloblasts, indicating the onset of AML. A bone marrow smear showed multilineage dysplasia, consistent with MDS evolution. Chromosomal analysis showed an additional t(9;22)(q34;q11) translocation. Because progression occurred concurrently with emergence of the Ph chromosome, we diagnosed this case as Ph‐positive AML with basophilia arising from the clonal evolution of MDS. The patient was initially treated with nilotinib. A hematological response was soon achieved with disappearance of the Ph chromosome in the bone marrow. Emergence of Ph‐positive AML in the course of low‐risk MDS has rarely been reported. We report this case as a rare clinical course of MDS.

Immune-mediated peripheral neuropathy occurring simultaneously with recurrent graft-versus-host disease after allogenic hematopoietic stem cell transplantation

Peripheral neuropathy is a rare but important complication f allogenic hematopoietic stem cell transplantation (allo-HSCT). lthough it is potentially curable, it sometimes has a tremendous mpact on a patient’s quality of life. There have been reports of nflammatory peripheral neuropathy associated with chronic graftersus-host disease (GVHD), but its pathogenesis has not been ully revealed. We report a case of immune-mediated neuropahy after allo-HSCT for Philadelphia-chromosome-positive acute ymphoblastic leukemia (Ph-ALL). After conditioning with cyclophosphamide + total body irradition, a 44-year-old woman in the second molecular complete emission (mCR) of Ph-ALL underwent allogenic peripheral blood ematopoietic stem cell transplantation from her sister, with a oneocus mismatch of histocompatibility leukocyte antigen-B antigen. yclosporine A (CsA), short-term methotrexate, and mycophenoatemofetil were administered for GVHD prophylaxis. Grade 3 acute VHD (skin: stage 1, liver: stage 0, gut: stage 2) had diagnosed on ay24 had occurred and was treated effectively with methylpredisolone (mPSL) 2 mg/kg/day. Thereafter, no recurrence of GVHD ymptoms had been seen, despite a gradual reduction in the doses f CsA and steroid, and bone marrow examinations had revealed hat the patient continued to be in mCR from Ph-ALL (Fig. 1). On day 240, the patient developed a self-limiting common cold. rom around day 250, she became aware of gradually worsening uscle weakness in the left upper extremity (at the time CsA was 0 mg b.i.d. and steroid was 10 mg q.d. as prednisolone, CsA had still ept on being reduced every two weeks). At a regular consultation n day 273, GVHD symptoms (generalized skin rash, dry eyes, and tomatitis) were noticed. Blood examination showed extremely levated hepatic enzymes (AST 192 U/L [normal range: 13–33 U/L], LT 408 U/L [6–30 U/L], -GTP 766I U/L [10–47 U/L], ALP 1018 U/L 115–359 U/L], and T-bil 0.6 mg/L [0.2–1.0 mg/L]). As for immune econstitution, serum IgG was 955 mg/dL [870–1700 mg/dL], WBC as 7700/ L [3800–8500/ L] and lymphocyte was 14% [20–45%]. ymphocyte subsets were not examined. The patient was admited to hospital and underwent skin biopsy and echo-guided liver iopsy. The biopsy specimens were consistent with GVHD. Manual uscle testing (MMT) showed a weakness of 4 in the left trapezus, 3 in the left deltoid muscle, 0 in the left biceps and 4 in the

Effects of recombinant G‐CSF and GM‐CSF on in vitro differentiation of the blast cells of RAEB and RAEB‐T

To evaluate the effects of recombinant G‐CSF and GM‐CSF on RAEB and RAEB‐T cells, blast cells from 6 patients were incubated in liquid culture systems with these CSFs for 7 days, and their numerical, morphological and functional changes were assessed. Both CSFs stimulated cell growth, but decreased the proportion of blast cells in 5 of the 6 cases. Karyotypic abnormalities persisted during cultivation in some cases. The CSFs also stimualted the expression of part of the esterase activities, and a positive interaction of both CSFs was seen in part. Although CSFs had no significant effects on the ability of cells to reduce NBT or to phagocytize latex particles, the results indicated that they induce partial differentiation of blast cells. It appears that such pathological cells still retain the capacity to respond to growth factors.

Successful treatment with rituximab for angioimmunoblastic T-cell lymphoma

We experienced a patient with angioimmunoblastic T-cell lymphoma (AITL) without Epstein-Barr virus-positive B (EBV-B) cells at initial presentation who progressed to AITL with expansion of EBV-B cells at relapse. Based on the results of repeated biopsy, the patient was successfully treated with rituximab in combination with chemotherapy at relapse. A repeat biopsy may be necessary to determine the optimum therapeutic strategy at relapse, particularly for patients with suspected expansion of B cell and/or EBV-B cells. Although a recent report found no significant prognostic advantage of rituximab, it is one of the active drugs for selected patients with AITL.

Reversible posterior leukoencephalopathy syndrome of bilateral thalamus in acute lymphoblastic leukemia

Numerous cases of reversible posterior leukoencephalopathy syndrome (RPLS) are reported in patients having risk factors such as malignant hypertension, eclampsia, receiving solid organ/hematopoietic stem cell transplant, and exposure to chemotherapeutic agents and immunosuppressive drugs. We experienced a very interesting case of atypical RPLS in the thalamus bilaterally accompanied by brain hemorrhage in acute lymphoblastic leukemia (ALL), and described here. A 62-year-old Japanese female was referred to our hospital with fever, general fatigue and leukocytosis in May 2011. Her white blood cell count was 139.6 10 9 /L, of which lymphoblasts constituted 96%, hemoglobin level was 8.2 g/ dL and platelet count was 15.0 10 9 /L. Leukemic lymphoblasts were peroxidase negative and their surface markers were positive for CD10, CD19, CD34 and human leukocyte antigen (HLA)-DR. Th e karyotype was 46, XY; the BCR/ABL fusion gene was not detected. Th e patient was diagnosed as having ALL and treated with cyclophosphamide, vincristine, adriamycin and prednisolone. Although leukemia cells were not present in peripheral blood at 9 days after starting chemotherapy, febrile neutropenia occurred, and antibiotic treatment was started immediately. After the administration of antibiotic and antifungal agents, erythroderma developed on her trunk, extremities and back. Stevens – Johnson syndrome (SJS) was diagnosed, and high-dose methylprednisolone was given. Hyponatremia (124 mEq/L) also occurred at this time, as an eff ect of the chemotherapeutic agents. Although the erythroderma and hyponatremia improved slowly over the next 4 days, her level of consciousness decreased gradually before falling suddenly, accompanied by high fever. Blood culture was positive for Pseudomonas aeruginosa while cerebrospinal fl uid (CSF) culture was negative. Th e patient ’ s level of consciousness improved after antibiotic treatment for sepsis; however, she lost consciousness once more, accompanied by high blood pressure (180/118 mmHg). Emergency computed tomography (CT) of the brain revealed multiple low-density areas in the thalamus, midbrain and pons bilaterally. Magnetic resonance imaging (MRI) of the brain performed 2 days after the CT scan showed multiple high signal intensity lesions with small hemorrhagic areas on T2-weighted fl uid attenuated inversion recovery imaging, T2 star-weighted imaging and diff usion-weighted imaging (Figure 1). No thrombosis of the bilateral internal vein and Galen vein was detected in brain CT and MRI. At 10 days after completion of treatment for sepsis and control of blood pressure, the patient was fully conscious. She was diagnosed with hemorrhage in atypical RPLS. MRI obtained 2 months after treatment showed no RPLS lesions

In vivo effect of a large amount of allogeneic granulocytes on reconstitution of hemopoietic cells of irradiated mice

The in vivo effects of allogeneic granulocytes on the reconstitution of splenic and bone marrow CFUs and CFUc numbers were investigated using irradiated mice. When allogeneic granulocytes were intraperitoneally injected into irradiated BDF1 mice (260 rads), the reconstitution of CFUs in both spleen and bone marrow as well as the hematocrit were enhanced, while the reconstitution of splenic or bone marrow CFUc numbers was transiently suppressed and then enhanced. The magnitude of enhancement was dose-dependent. These results suggest that granulocytes injected into irradiated mice might act as enhancing effectors on the in vivo reconstitution of hemopoietic cells.