title: Evaluation of an algorithm based on peripheral blood hematopoietic progenitor cell and CD34+ cell concentrations to optimize peripheral blood progenitor cell collection by apheresis.
abstract: BACKGROUND
  Quantification of peripheral blood (PB) CD34+ cells is commonly used to plan peripheral blood progenitor cell (PBPC) collection but is time-consuming. Sysmex has developed a hematology analyzer that can quickly identify a population of immature hematopoietic cells (HPCs) according to cell size, cell density, and differential lysis resistance, which may indicate the presence of PBPCs in PB. This prospective study has evaluated the potential of such method to predict the PBPC mobilization.
  
  
  METHODS
  A total of 141 patients underwent PBPC mobilization. PB HPCs and PB CD34+ cells were simultaneously quantified with a hematology analyzer (SE2100, Sysmex) and flow cytometry, respectively. The number of blood volumes processed was then based on PB CD34+ cell concentration.
  
  
  RESULTS
  The optimal PB HPC level able to predict a minimal level of 10 x 10(6) PB CD34+ cells per L was 5 x 10(6) per L with positive and negative predictive values of 0.93 and 0.36 percent, respectively. For this cutoff point, sensitivity and specificity were 0.81 and 0.65, respectively. The median number of blood volumes processed according to the PB CD34+ cell count allowed us to perform only one apheresis procedure for a majority of patients.
  
  
  CONCLUSIONS
  PB HPC quantification is very useful to quickly determine the initiation of PBPC apheresis especially for patients with higher concentrations. For patients exhibiting a lower HPC count (<5 x 10(6)/L), other parameters such as a CD34 test may be needed. Such a policy associated with a length of apheresis adapted to the richness in the PB CD34+ cells allows for optimizing the organization of centers with an improvement in patient comfort and economical savings.
authors: Département de Biothérapie, Service d'Hématologie Adultes, and Laboratoire d'Hématologie, Hôpital Necker, 75743 Paris Cedex 15, France. francois.lefrere@nck.aphp.fr
authors: François
authors: F
authors: Lefrère
authors: Sarah
authors: S
authors: Zohar
authors: Sandrine
authors: S
authors: Beaudier
authors: Françoise
authors: F
authors: Audat
authors: Jean-Antoine
authors: JA
authors: Ribeil
authors: David
authors: D
authors: Ghez
authors: Bruno
authors: B
authors: Varet
authors: Marina
authors: M
authors: Cavazzana-Calvo
authors: Liliane
authors: L
authors: Dal Cortivo
authors: Rémi
authors: R
authors: Letestu
authors: Elizabeth
authors: E
authors: McIntyre
authors: Chantal
authors: C
authors: Brouzes
mesh_terms: D000328:Adult; D000368:Aged; D000465:Algorithms; D015703:Antigens, CD / Q000097:blood; D018952:Antigens, CD34 / Q000097:blood*; D001781:Blood Component Removal / Q000379:methods*; D019650:Hematopoietic Stem Cell Mobilization / Q000379:methods*; D006412:Hematopoietic Stem Cells / Q000166:cytology*; D006801:Humans; D007938:Leukemia / Q000097:blood / Q000628:therapy; D008223:Lymphoma / Q000097:blood / Q000628:therapy; D008875:Middle Aged; D009369:Neoplasms / Q000097:blood / Q000628:therapy; D012680:Sensitivity and Specificity
chemical_list: D015703:Antigens, CD; D018952:Antigens, CD34