Klin Padiatr 2011; 223 - A26
DOI: 10.1055/s-0031-1277087

In acute lymphoblastic leukaemia stemness is frequent and ubiquitous

K Rehe 1, K Wilson 1, S Bomken 1, M Stanulla 2, O Heidenreich 1, J Vormoor 1
  • 1NICR, Newcastle University, UK
  • 2Department of Pediatrics, University of Schleswig-Holstein, Kiel, Germany

Introduction: In ALL conflicting results persist regarding the frequency and identity of leukaemia-initiating cells, which self-renew and reconstitute the full original phenotype.

Methods: Unsorted cells and sorted fractions (CD10, CD20 and CD34 high and low expression) from 30 ALL's of different risk groups were transplanted intrafemorally into NSG mice. Engraftment of serial transplantations and limiting dilutions (10–10,000 cells/mouse) was analysed by flow cytometry. Expression of self-renewal associated genes was investigated by real time PCR in CD34 high and low sorted blasts.

Results: Unsorted blasts and sorted fractions irrespective of the expression of CD10, CD20 or CD34 engraft NSG mice and re-establish the complete original immunephenotype in serial transplantations and in limiting dilution experiments down to 10–100 cells. The expression of a selection of self-renewal associated genes was not dependent on the CD34 status of blasts.

Conclusion: In B precursor ALL a broad spectrum of blast immunephenotypes show evidence of stem cell properties and these characteristics are highly frequent among ALL blasts.