title: Spontaneous erythroid colony formation in Brazilian patients with sickle cell disease.
abstract: The ability of circulating progenitor cells to develop erythroid colonies was studied in vitro in the presence or absence of growth factors (5637-CM and erythropoietin) in 63 patients with sickle cell disease (SCD) (36 homozygotes for hemoglobin [Hb] S, 13 double heterozygotes for Hb S and beta thalassemia, and 14 SC patients) in Southeast Brazil. In the presence of growth factors, SCD patients (all genotypes) presented significantly higher numbers of circulating burst-forming unit-erythroid (BFU-E/5 x 10(5) MNC), when compared with control subjects. However, when the progenitor cells were cultured in the absence of added stimulus, high numbers of BFU-E were observed only in the genotypes SS and S/beta thalassemia. SC patients presented a similar response to the control subjects. Moreover, there was an inverse correlation between spontaneous (without stimulus) BFU-E and Hb levels in SCD patients. These results suggest that the formation of spontaneous BFU-E observed in SCD may be due to an expanded erythropoiesis secondary to hemolysis.
authors.affiliation: Department of Physiology, State University of Campinas-UNICAMP, Brazil.
authors.forename: R C
authors.initials: RC
authors.lastname: Perlingeiro
authors.forename: F F
authors.initials: FF
authors.lastname: Costa
authors.forename: S T
authors.initials: ST
authors.lastname: Saad
authors.forename: V R
authors.initials: VR
authors.lastname: Arruda
authors.forename: M L
authors.initials: ML
authors.lastname: Queiroz
mesh_terms: D000328:Adult; D000755:Anemia, Sickle Cell / Q000097:blood*; D001938:Brazil; D002454:Cell Differentiation; D002455:Cell Division; D003114:Colony-Forming Units Assay; D015672:Erythroid Precursor Cells / Q000166:cytology*; D004921:Erythropoietin / Q000494:pharmacology; D005838:Genotype; D006450:Hemoglobin SC Disease / Q000097:blood / Q000235:genetics; D006801:Humans; D011994:Recombinant Proteins; D012805:Sickle Cell Trait / Q000097:blood / Q000150:complications / Q000235:genetics; D017086:beta-Thalassemia / Q000097:blood / Q000150:complications / Q000235:genetics
chemical_list: D011994:Recombinant Proteins; D004921:Erythropoietin