title: The in vitro effect of high-dose recombinant human erythropoietin on granulocyte-macrophage colony production in premature infants using a defined serum deprived cell culture system.
abstract: Recent reports of neutropenia associated with the use of recombinant human erythropoietin (r-HuEpo) in preterm infants with the anaemia of prematurity have raised concern over the clinical use of this hormone. The present studies were undertaken to determine whether high-dose r-HuEpo has an effect on granulocyte production in vitro. The studies used a serum deprived, optimized semi-solid cell culture system to investigate the effect of lineage specific and non-specific granulocyte and erythroid colony stimulating factors on circulating peripheral blood granulocyte-macrophage colony forming units (CFU-GM), erythroid burst forming units (BFU-E) and multilineage colonies (CFU-Mix) from nine premature infants and seven healthy adults. CFU-GM were grown in the presence of interleukin 3 (IL3) 8 ng/ml, granulocyte-macrophage colony stimulating factor (GM-CSF) 20 ng/ml and granulocyte colony stimulating factor (G-CSF) 15 ng/ml alone and combinations of G-CSF with GM-CSF or IL3. The number, size and differentiation of CFU-GM colonies were then analysed in the presence and absence of high dose r-HuEpo (4 U/ml). High-dose r-HuEpo did not exert any significant modulatory effects on the number of CFU-GM colonies produced in the presence of IL3, GM-CSF and G-CSF alone or in combination. The number of cells within each CFU-GM colony did not change significantly, nor was there a significant change in the degree of differentiation. The combined number of BFU-E, CFU-GM and CFU-Mix colonies increased with r-HuEpo in both adults (1.8 x) and preterm infants (1.4 x), almost exclusively due to an increase in BFU-E derived colonies. Thus, no evidence was found for an r-HuEpo mediated redirection of multipotential haemopoietic stem cells into committed erythroid precursors at the expense of myeloid precursors.
authors.affiliation: Department of Immunology, United Medical and Dental School, Guys Hospital, London.
authors.forename: C S
authors.initials: CS
authors.lastname: Ward
authors.forename: N B
authors.initials: NB
authors.lastname: Westwood
authors.forename: A J
authors.initials: AJ
authors.lastname: Emmerson
authors.forename: T C
authors.initials: TC
authors.lastname: Pearson
mesh_terms: D002454:Cell Differentiation / Q000187:drug effects / Q000502:physiology; D002455:Cell Division / Q000187:drug effects / Q000502:physiology; D002478:Cells, Cultured; D016895:Culture Media, Serum-Free / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D004921:Erythropoietin / Q000494:pharmacology*; D005260:Female; D016179:Granulocyte Colony-Stimulating Factor / Q000494:pharmacology; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000494:pharmacology; D006098:Granulocytes / Q000166:cytology* / Q000187:drug effects / Q000502:physiology; D006410:Hematopoiesis / Q000187:drug effects / Q000502:physiology; D006412:Hematopoietic Stem Cells / Q000187:drug effects / Q000502:physiology; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature / Q000502:physiology*; D007377:Interleukin-3 / Q000494:pharmacology; D008264:Macrophages / Q000166:cytology* / Q000187:drug effects / Q000502:physiology; D008297:Male; D011994:Recombinant Proteins / Q000494:pharmacology
chemical_list: D016895:Culture Media, Serum-Free; D007377:Interleukin-3; D011994:Recombinant Proteins; D004921:Erythropoietin; D016179:Granulocyte Colony-Stimulating Factor; D016178:Granulocyte-Macrophage Colony-Stimulating Factor