In recent years autologous stem cell transplantation has been increasingly used in haematological disorders. CD34+ progenitor cell counts and haematopoietic clonogenic potential have been widely studied as laboratory parameters capable of predicting engraftment following myeloablative treatment. However, factors predicting successful stem cell mobilisation and engraftment are widely discussed. The aims of this study were: 1) to evaluate which CD34+ cell subsets contained in leucapheresis products could be regarded as the most predictive of long-term haematopoietic recovery after autologous peripheral blood stem cell transplantation (auto-PBSCT), and 2) to identify clinical and biological factors predicting successful mobilisation. To reach the first goal, in a restricted group of 34 patients the total amounts of CD34+ cells and CD34+ cell subsets, defined by the expression of CD123 (a subunit of IL-3/R), CD133 (AC133), HLA-DR, CD38, CD117 (c-kit/R), and CD90 (Thy-1) antigens, were correlated with the numbers of short-term (i.e. colony forming cells-CFC) and long-term culture-CFC (LTC-CFC) (generated at the 5th week of culture), and with the kinetics of haematopoietic engraftment following auto-PBSCT. Our data demonstrated that some of the most primitive progenitor subsets (CD34+/CD117-/HLA-DR-, and CD34+/CD38+/HLA-DR-) showed the strongest correlation with LTC-CFC numbers generated within the autologous stroma, while no significant correlation was noted using normal bone marrow stroma or the M210B4 cell line. Clinical data showed that long-term platelet and neutrophil engraftment after auto-BMT seems to be associated with CD34+/CD38+/HLA-DR- and CD34+/ CD117-/HLA-DR- cell numbers. Long-term platelet engraftment was also correlated with the total quantity of LTC-CFC infused. These data support the hypothesis that some CD34+ cell subsets are more reliable predictors of long-term haematopoietic recovery rates than total CD34+ cell quantity. Analysis of data obtained from 139 patients with different haematological disorders showed that age, platelet number before mobilisation, and previous chemotherapy are the most useful clinical factors for predicting the adequacy of the stem cell collection (CD34+ cells > 5×106/Kg ).
|Number of pages||15|
|Publication status||Published - 2003|
ASJC Scopus subject areas
- Immunology and Allergy