title: Defects of granulopoiesis in patients with severe congenital neutropenia.
abstract: To confirm the abnormalities of primitive myeloid progenitor cells in patients with severe congenital neutropenia (SCN), we studied their responsiveness to hematopoietic factors including granulocyte colony-stimulating factor (G-CSF). In all SCN patients studied no abnormalities of granulocyte colony-stimulating factor receptor (G-CSFR) gene were detected by polymerase chain reaction-single-strand conformation polymorphism analysis and sequence analysis. A flow cytometric analysis of bone marrow cells based on the expression of CD34, Kit receptor, and G-CSFR demonstrated a reduced frequency of CD34+/Kit+/G-CSFR+ cells in patients with SCN. The granulocyte/macrophage (GM)-colony formation of CD34+/Kit+/G-CSFR+ cells in patients was markedly decreased at all concentrations of G-CSF in serum-deprived semisolid culture. The responsiveness of CD34+/Kit+/G-CSFR+ cells in patients showed a reduced response to the combination of stem cell factor, the ligand for flk2/flt3, and interleukin-3 with or without G-CSF in serum-deprived semisolid and liquid suspension cultures. In contrast, no difference in the responsiveness of CD34+/Kit+/G-CSFR- cells was noted between SCN patients and normal subjects. The bone marrow cells from a patient who underwent bone marrow transplantation showed a restoration of both the reduced frequency and the decreased level of GM-colony formation of CD34+/Kit+/G-CSFR+ cells. These results demonstrate that the presence of qualitative and quantitative abnormalities of primitive myeloid progenitor cells expressing G-CSFR may play an important role in the impairment of granulopoiesis in patients with SCN.
authors.affiliation: Department of Pediatrics, Hiroshima University School of Medicine, Japan.
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Nakamura
authors.forename: Masao
authors.initials: M
authors.lastname: Kobayashi
authors.forename: Nakao
authors.initials: N
authors.lastname: Konishi
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kawaguchi
authors.forename: Shin-ichiro
authors.initials: S
authors.lastname: Miyagawa
authors.forename: Takashi
authors.initials: T
authors.lastname: Sato
authors.forename: Osamu
authors.initials: O
authors.lastname: Katoh
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Ueda
mesh_terms: D018952:Antigens, CD34 / Q000378:metabolism; D001483:Base Sequence; D003114:Colony-Forming Units Assay; D004247:DNA / Q000235:genetics; D005260:Female; D016179:Granulocyte Colony-Stimulating Factor / Q000494:pharmacology; D006098:Granulocytes / Q000473:pathology; D006412:Hematopoietic Stem Cells / Q000187:drug effects / Q000473:pathology; D006801:Humans; D066298:In Vitro Techniques; D007223:Infant; D008297:Male; D038042:Myelopoiesis / Q000187:drug effects; D009503:Neutropenia / Q000151:congenital* / Q000235:genetics / Q000473:pathology; D015513:Oncogene Proteins / Q000378:metabolism; D019009:Proto-Oncogene Proteins c-kit; D016188:Receptors, Granulocyte Colony-Stimulating Factor / Q000235:genetics / Q000378:metabolism
chemical_list: D018952:Antigens, CD34; D015513:Oncogene Proteins; D016188:Receptors, Granulocyte Colony-Stimulating Factor; D016179:Granulocyte Colony-Stimulating Factor; D004247:DNA; D019009:Proto-Oncogene Proteins c-kit