title: Involvement of placental/umbilical cord blood acid-base status and gas values on the radiosensitivity of human fetal/neonatal hematopoietic stem/progenitor cells.
abstract: Arterial cord blood (CB) acid-base status and gas values, such as pH, PCO2, PO2, HCO3(-)and base excess, provide useful information on the fetal and neonatal condition. However, it remains unknown whether these values affect the radiosensitivity of fetal/neonatal hematopoiesis. The present study evaluated the relationship between arterial CB acid-base status, gas values, and the radiosensitivity of CB hematopoietic stem/progenitor cells (HSPCs). A total of 25 CB units were collected. The arterial CB acid-base status and gas values were measured within 30 min of delivery. The CD34(+)HSPCs obtained from CB were exposed to 2 Gy X-irradiation, and then assayed for colony-forming unit-granulocyte-macrophage, burst-forming unit-erythroid (BFU-E), and colony-forming unit-granulocyte erythroid, macrophage and megakaryocyte cells. Acid-base status and gas values for PCO2and HCO3(-)showed a statistically significant negative correlation with the surviving fraction of BFU-E. In addition, a significant positive correlation was observed between gestational age and PCO2. Moreover, the surviving fraction of BFU-E showed a significant negative correlation with gestational age. Thus, HSPCs obtained from CB with high PCO2/HCO3(-)levels were sensitive to X-irradiation, which suggests that the status of arterial PCO2/HCO3(-)influences the radiosensitivity of fetal/neonatal hematopoiesis, especially erythropoiesis.
authors.affiliation: Department of Radiological Life Sciences, Division of Medical Life Science, Hirosaki University Graduate School of Health Sciences, 66-1 Hon-cho, Hirosaki, Aomori 036-8564, Japan.
authors.forename: Masaru
authors.initials: M
authors.lastname: Yamaguchi
authors.forename: Satoko
authors.initials: S
authors.lastname: Ebina
authors.forename: Ikuo
authors.initials: I
authors.lastname: Kashiwakura
mesh_terms: D000328:Adult; D001784:Blood Gas Analysis; D002245:Carbon Dioxide / Q000097:blood; D002254:Carbonates / Q000097:blood; D002470:Cell Survival / Q000528:radiation effects; D002478:Cells, Cultured; D004307:Dose-Response Relationship, Radiation; D005260:Female; D005312:Fetal Blood / Q000737:chemistry*; D053686:Fetal Stem Cells / Q000737:chemistry* / Q000528:radiation effects*; D006412:Hematopoietic Stem Cells / Q000737:chemistry* / Q000528:radiation effects*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007231:Infant, Newborn; D010920:Placenta / Q000098:blood supply / Q000737:chemistry; D011247:Pregnancy; D011836:Radiation Tolerance / Q000502:physiology*; D055815:Young Adult
chemical_list: D002254:Carbonates; D002245:Carbon Dioxide