First experience of CD34+ cell selection to high-risk neuroblastoma patients
Yulia A. Yakovleva1,2, Grigory A. Tsaur1,2, Alexander M. Popov1,2,3, Tatyana Yu. Verzhbitskaya1,2, Igor N. Vyatkin1,2, Andrey A. Igumenshev1,2, Natalya G. Maisheva1,2, Anton Yu. Zadoya1,2, Egor V. Shorikov1,2, Leonid I. Savelyev1,2,3, Larisa G. Fechina1,2
1Regional Children Hospital 1, Ekaterinburg, Russia; 2Research Institute of Medical Cell Technologies, Ekaterinburg, Russia;
3Ural State Medical Academy, Ekaterinburg, Russia
Summary
Objective
To estimate the applicability of CD34+ cell selections using CliniMACS plus equipment (Milteni Biotec).
Methods
From June 2007 to April 2008 eight selections were performed on 7 children with high-risk neuroblastoma (stage 4). In 4 patients peripheral blood stem cells (PBSC) were mobilized with G-CSF (10 µg/kg/day) for 6 days and leukapheresis was performed on days 5 and 6 of G-CSF administration by the “Cobe Spectra” cell separator (Gambro). In 2 patients bone marrow (BM) was used for the CD34+ cell selection. In 1 patient PBSC and BM were used consecutively. The total number of nucleated cells was measured by Sysmex KX 21 (Roche) before and after CD34+ cell selections. The number and viability of cells were assessed by the “FACSCanto II” flow cytometer (BD, USA).
Results
Before CD34+ selection, the median percentage of CD 34+ cells in harvested cells was 1.64% (0.23–5.5). The median dose of CD34+ cells per 1 kg of patients body weight was 10.64*106 (1.61–42.37*106). After CD34+ selection, the median of selected CD34+ cells per 1 kg of weight was 4.93*106 (1.42–14.5*106) with a median purity of 96.74% (88.2–97.7%).
The viability of isolated CD34+ cells was 91.8% (71.6–99.6%). The median time to achievement of 500/µl ANC was 34 days (28–40).
Conclusion
Immunomagnetic selection of CD34+ cells by CliniMACS allows the obtainment of viable and highly purified autologous CD34+ cells. CD34+ selection leads to delayed hematopoietic recovery in our patients.
Keywords
high-risk neuroblastoma, children, CD34+ cell selection
