title: Mini buffy coat photopheresis for children and critically ill patients with extracorporeal photopheresis contraindications.
abstract: BACKGROUND
  Conventional extracorporeal photopheresis (ECP) has proven efficacy for the treatment of several diseases but is limited to patients with sufficient body weight. A novel simplified mini buffy coat ECP technique that allows treatment of small children and patients with apheresis contraindications has been developed.
  
  
  METHODS
  White blood cell (WBC)-rich buffy coat fractions were prepared from 5 to 8 mL/kg whole blood in a closed system, diluted, and ultraviolet A (UVA)-irradiated after addition of 8-methoxypsoralen (8-MOP). Apoptosis and cell death were analyzed by annexin V and 7-aminoactinomycin staining. Lymphocyte proliferation was measured after CD3/CD28 and phytohemagglutinin (PHA) stimulation. Autologous residual blood and UVA-irradiated buffy coat were returned to the patients. Fifty-six mini buffy coat ECP procedures were applied to three children with acute steroid-refractory skin graft-versus-host disease and apheresis contraindications.
  
  
  RESULTS
  Mean whole blood and buffy coat volumes were 166 (+/-61.8) and 8 (+/-1.6) mL, respectively, and resulted in a hematocrit of 2.2% (+/-0.4) after saline dilution (median +/- SD). UVA irradiation of 8-MOP buffy coat preparations resulted in significant induction of WBC apoptosis at 48-72 hours (p <or= 0.006). WBC proliferation was significantly inhibited both after CD3/CD28 stimulation and after PHA stimulation when compared to controls (p <or= 0.001). No clinical or laboratory side effects were observed during mini ECP procedures and the three patients responded to the therapy.
  
  
  CONCLUSIONS
  Mini buffy coat ECP induces apoptosis and lymphocyte proliferation inhibition, both of which occur after standard ECP. This study proposes that mini buffy coat ECP be used as a simple and inexpensive alternative to classical ECP in children and adult patients with apheresis contraindications.
authors.affiliation: Institute for Clinical Immunology and Transfusion Medicine and the Department of Pediatric Hematology and Oncology, Justus-Liebig University Giessen, Giessen, Germany. holger.hackstein@immunologie.med.uni-giessen.de
authors.forename: Holger
authors.initials: H
authors.lastname: Hackstein
authors.forename: Joachim
authors.initials: J
authors.lastname: Misterek
authors.forename: Angelika
authors.initials: A
authors.lastname: Nockher
authors.forename: Alfred
authors.initials: A
authors.lastname: Reiter
authors.forename: Gregor
authors.initials: G
authors.lastname: Bein
authors.forename: Willi
authors.initials: W
authors.lastname: Woessmann
mesh_terms: D000293:Adolescent; D049109:Cell Proliferation; D002675:Child, Preschool; D016638:Critical Illness / Q000628:therapy*; D006086:Graft vs Host Disease / Q000628:therapy; D006801:Humans; D007962:Leukocytes / Q000166:cytology; D017893:Photopheresis / Q000379:methods*; D013601:T-Lymphocytes / Q000166:cytology