title: The influence of automated plateletpheresis on systemic levels of hematopoietic growth factors.
abstract: BACKGROUND
  Megakaryocytopoiesis and platelet production are regulated by several hematopoietic growth factors. The present study focuses on the effects of automated plateletpheresis on systemic levels of different hematopoietic growth factors.
  
  
  METHODS
  Platelet count, mean platelet volume, and serum levels of thrombopoietin, erythropoietin, interleukin-1beta, interleukin-6, and stem cell factor in 21 healthy donors were measured before platelet collection, after the first half of the apheresis procedure, at the end of apheresis, and on Days 1, 2, and 7 thereafter.
  
  
  RESULTS
  Thrombopoietin levels (initial level: 49.5 +/- 25.5 pg/mL) showed a significant increase between measurements taken at the end of apheresis and Day 1 (56.9 +/- 26.7 pg/mL; p = 0.01). There was a highly significant decrease in stem cell factor levels during apheresis (p<0.0005), reaching preapheresis values (1679 +/- 210 pg/mL) on Day 1. A highly significant increase in erythropoietin levels (initial level: 7.5 +/- 4.0 U/L) was seen after apheresis (p<0.0005 on Days 1 and 2). The level remained significantly elevated until Day 7 (p = 0.004). Interleukin-1beta and interleukin-6 levels (before donation: 1.4 +/- 1.8 pg/mL and 1.1 +/- 0.7 pg/mL, respectively) did not change during the observation period. Thrombopoietin levels correlated consistently and inversely with stem cell factor levels after apheresis (Day 1, r = -0.46, p = 0.035; Day 2, r = -0.50, p = 0.02; Day 7, r = -0.50, p = 0.02).
  
  
  CONCLUSIONS
  The data show a coordinated response of the hematopoietic system to platelet loss. It is suggested that the decrease in serum stem cell factor levels during apheresis reflects the consumption of stem cell factor by early hematopoietic progenitors that expand to initiate early megakaryocytopoiesis. The temporary increase in thrombopoietin is the result of platelet loss and serves as a stimulus for subsequent thrombopoiesis. The pronounced elevation of erythropoietin after apheresis suggests a role for this primarily erythropoietic cytokine in thrombopoiesis, too.
authors.affiliation: Department of Transfusion Medicine and Hemostaseology, Friedrich-Alexander-University Erlangen-Nuremberg, Erlangen, Federal Republic of Germany. volker.weisbach@trans.med.uni-erlangen.de
authors.forename: V
authors.initials: V
authors.lastname: Weisbach
authors.forename: H
authors.initials: H
authors.lastname: Friedlein
authors.forename: A
authors.initials: A
authors.lastname: Glaser
authors.forename: J
authors.initials: J
authors.lastname: Zingsem
authors.forename: R
authors.initials: R
authors.lastname: Zimmermann
authors.forename: R
authors.initials: R
authors.lastname: Eckstein
mesh_terms: D000293:Adolescent; D000328:Adult; D001782:Blood Donors; D004921:Erythropoietin / Q000097:blood; D016298:Hematopoietic Cell Growth Factors / Q000097:blood*; D006801:Humans; D007375:Interleukin-1 / Q000097:blood; D008297:Male; D008875:Middle Aged; D010976:Platelet Count; D010983:Plateletpheresis; D019089:Stem Cell Factor / Q000097:blood; D013926:Thrombopoietin / Q000097:blood
chemical_list: D016298:Hematopoietic Cell Growth Factors; D007375:Interleukin-1; D019089:Stem Cell Factor; D004921:Erythropoietin; D013926:Thrombopoietin