title: Collection of blood stem cells from patients with sickle cell anemia.
abstract: Prior to initiating gene therapy trials for sickle cell disease (SCD), methods to collect sufficient numbers of hematopoietic stem and progenitor cells will need to be developed. Bone marrow harvest entails significant morbidity that could be severe in patients with SCD. In addition, an ability to perform repeated stem cell collections so that several transfers of genetically modified cells could be attempted would be advantageous. In other settings, apheresis collection of mobilized blood stem cells has become the preferred source of stem cells for transplantation. Unfortunately, patients with SCD do not tolerate granulocyte-colony stimulating factor and therefore cannot be mobilized using these conventional methods. In this pilot study, we investigated whether withdrawal of hydroxyurea therapy results in an increase in circulating numbers of CD34+ cells and hematopoietic progenitors. In addition, we performed leukapheresis in one patient with severe SCD in an attempt to determine whether blood stem cell collection can be performed safely in patients who would be candidates for SC gene therapy trials. Our results highlight some of the potential difficulties in initiating gene therapy clinical trials for sickle cell disease.
authors.affiliation: Division of Hematology, Department of Medicine, University of Washington School of Medicine, Mailstop 357710, HSB, Seattle, WA 98195, USA.
authors.forename: Robert E
authors.initials: RE
authors.lastname: Richard
authors.forename: Noppadol
authors.initials: N
authors.lastname: Siritanaratkul
authors.forename: Erica
authors.initials: E
authors.lastname: Jonlin
authors.forename: Eva
authors.initials: E
authors.lastname: Skarpidi
authors.forename: Shelly
authors.initials: S
authors.lastname: Heimfeld
authors.forename: C Anthony
authors.initials: CA
authors.lastname: Blau
mesh_terms: D000328:Adult; D000755:Anemia, Sickle Cell / Q000097:blood* / Q000188:drug therapy / Q000473:pathology; D018952:Antigens, CD34 / Q000032:analysis; D005260:Female; D015316:Genetic Therapy; D019650:Hematopoietic Stem Cell Mobilization; D006412:Hematopoietic Stem Cells / Q000187:drug effects / Q000276:immunology* / Q000473:pathology; D006801:Humans; D006918:Hydroxyurea / Q000627:therapeutic use; D007937:Leukapheresis; D008297:Male; D010865:Pilot Projects
chemical_list: D018952:Antigens, CD34; D006918:Hydroxyurea