title: Failure to achieve a threshold dose of CD34+ CD110+ progenitor cells in the graft predicts delayed platelet engraftment after autologous stem cell transplantation.
abstract: In this study, we retrospectively analysed the utility of CD110 expression on CD34(+) cells as a predictor of delayed platelet transfusion independence in 39 patients who underwent autologous peripheral blood stem cell transplantation. Absolute CD34(+) cells and CD34(+) subsets expressing CD110 were enumerated using flow cytometry. Of the 39 patients, 7 required 21 days or more to achieve platelet transfusion independence. Six of the seven patients received a dose of CD34(+)CD110(+) cells below 6.0 x 10(4)/kg while 30 of 32 patients who achieved platelet transfusion independence in <21 days received a dose of CD34(+)CD110(+) cells >6.0 x 10(4)/kg (P<0.001). Patients with delayed platelet engraftment received a median dose of 5.2 x 10(4) CD34(+)CD110(+) cells/kg compared with a median dose of 16.4 x 10(4) cells/kg for those engrafting within 21 days (P=0.003). Further analysis showed that >6.0 x 10(4) CD34(+)CD110(+) cells/kg was highly sensitive (93.8%) and highly specific (85.7%) for achieving platelet transfusion independence within 21 days. Delay in platelet transfusion independence translated into an increased requirement for platelet transfusion (median 6 vs 2 transfusions, P<0.0001). The dose of CD34(+)/CD110(+) cells/kg infused at time of transplantation appears to be an important factor identifying patients at risk of delayed platelet engraftment.
authors: Flow Cytometry Unit, Haematology Department, Leukaemia Research Laboratory, Westmead Hospital, University of Sydney, Sydney, NSW, Australia. mary@icpmr.wsahs.nsw.gov.au
authors: M M
authors: MM
authors: Sartor
authors: F
authors: F
authors: Garvin
authors: V
authors: V
authors: Antonenas
authors: K F
authors: KF
authors: Bradstock
authors: D J
authors: DJ
authors: Gottlieb
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D018952:Antigens, CD34; D001792:Blood Platelets / Q000502:physiology*; D002452:Cell Count; D002648:Child; D002675:Child, Preschool; D051799:Delayed Graft Function; D018380:Hematopoietic Stem Cell Transplantation / Q000379:methods*; D006412:Hematopoietic Stem Cells / Q000166:cytology*; D006801:Humans; D016130:Immunophenotyping; D008875:Middle Aged; D010976:Platelet Count; D017713:Platelet Transfusion; D012372:ROC Curve; D053628:Receptors, Thrombopoietin; D012189:Retrospective Studies; D014182:Transplantation, Autologous
chemical_list: D018952:Antigens, CD34; D053628:Receptors, Thrombopoietin