A new method for maturity-dependent fractionation of neutrophil progenitors applicable for the study of myelodysplastic syndromes.

We applied our new method, maturity-dependent fractionation of bone marrow-derived neutrophil progenitors, to a study of gene expression profiles during granulopoiesis in myelodysplastic syndromes. CD34+ cells with low density [F1], CD11b-/CD16- [F2], CD11b+/CD16- [F3] and CD11b+/CD16low [F4] with intermediate density, CD11b+/CD16int [F5] and CD11b+/CD16high [F6] with high density were isolated from six patients. Although AML1 and C/EBP-ϵ mRNA peaked at F1 and F4, respectively, in healthy individuals, C/EBP-ϵ was maximized at F2/F3 in all patients, two of whom showed simultaneous peaks of AML1 at F2.

Maturity-dependent fractionation of neutrophil progenitors: a new method to examine in vivo expression profiles of differentiation-regulating genes.

To investigate differentiation-dependent gene expression during granulopoiesis, we established a new method to isolate six sequential differentiation stages of neutrophil progenitors from bone marrow. Neutrophil progenitors were divided into three populations by density centrifugation, followed by depletion of other lineages, and further separated by fluorescence-activated cell sorting based on the expressions of CD34, CD11b, and CD16: CD34(+) fraction from a low-density population (F1), CD11b(-)/CD16(-) (F2), CD11b(+)/CD16(-) (F3), and CD11b(+)/CD16(low) (F4) fractions with intermediate density, and CD11b(+)/CD16(int) (F5) and CD11b(+)/CD16(high) (F6) fractions from a high-density population. To examine whether this fractionation was applicable to the study of in vivo gene expression profiles during granulopoiesis, we analyzed messenger RNA levels of AML-1 and CCAAT/enhancer binding protein (EBP)-ε and two target genes of C/EBP-ε, granulocyte-macrophage colony-stimulating factor receptor common β subunit and lactoferrin, in the six fractions and peripheral blood-derived neutrophils (F7).

Low concentration of serum haptoglobin has impact on understanding complex pathophysiology in patients with acquired bone marrow failure syndromes.

To clarify whether measurement of serum haptoglobin (Hp) has impact on understanding pathophysiology in bone marrow failure (BMF) syndromes, we investigated concentrations of serum Hp by nephelometric procedure in 156 Japanese patients with BMF, including 54 aplastic anemia (AA), 50 paroxysmal nocturnal hemoglobinuria (PNH), and 52 myelodysplastic syndromes (MDS) patients. The frequencies with low concentrations of serum Hp (<42 mg/dL) in PNH patients (98.0%) were significantly higher than those in AA (27.

Attenuation of diastolic heart failure and life-threatening ventricular tachyarrhythmia after peripheral blood stem cell transplantation combined with cardioverter-defibrillator implantation in myeloma-associated cardiac amyloidosis.

A patient had multiple myeloma and associated cardiac amyloidosis, which caused diastolic dysfunction and recurrent ventricular fibrillation. After implantation of a cardioverter-defibrillator (ICD), the patient underwent autologous peripheral blood stem cell transplantation (PBSCT). The life-threatening arrhythmias, such as ventricular fibrillation, disappeared, and diastolic dysfunction assessed by quantitative gated single photon emission computed tomography and Doppler echocardiography improved 7 months later.

The role of Wilms' tumor gene peptide-specific cytotoxic T lymphocytes in immunologic selection of a paroxysmal nocturnal hemoglobinuria clone.

Objective: To clarify an expansion mechanism of a paroxysmal nocturnal hemoglobinuria (PNH) clone with the Wilms' tumor gene (WT1).

Materials And Methods: In PNH patients with the HLA-A*2402 allele, frequencies of peripheral blood (PB) WT1 peptide-specific and HLA-A*2402-restricted CD8+ cells and WT1 peptide-stimulated interferon-gamma-producing mononuclear cells (MNCs), cytotoxicity of WT1 peptide-specific and HLA-A*2402-restricted cytotoxic T lymphocyte (CTL) clone (TAK-1) cells on bone marrow (BM) MNCs, and after co-incubation with TAK-1 cells, changes in colony-forming unit granulocyte-macrophage colony formation of CD34+ cells and in CD59 expression in viable CD34+ cells were investigated.

Results: The frequencies of PB WT1 peptide-specific and HLA-A*2402-restricted CD8+ cells (p < 0.

The frequency of HLA class I alleles in Japanese patients with bone marrow failure.

The frequencies of the HLA-B*4002 and HLA-A*0206 alleles in patients with aplastic anemia (AA) (n=32; 21.9%) and paroxysmal nocturanl hemoglobinuria (PNH) (n=24; 22.9%), respectively, were significantly different from those in controls (n=371; 8.