Fig. 2.

Quantification of marked clones. a Assuming each transplanted stem cell is uniquely marked, the initial number of CD34+ cells representing each clone is one. b The pre-transplant clone size distribution is thus defined by the total number of transplanted CD34+ cells and is peaked at one cell. Post-transplant proliferation and differentiation of the HSC clones result in a significantly broader clone size distribution in the peripheral blood. The number of differentiated cells for each clone and the number of clones represented by exactly k cells, 5 years’ post-transplantation (corresponding to Fig. 1a), are overlaid in (a) and (b) respectively. c Clone size distribution (blue) and the cumulative normalized clone size distribution (red) of the pre-transplant CD34+ population. d After transplantation, clone size distributions in the transit-amplifying (TA) and differentiated peripheral cell pools broaden significantly (with clones ranging over four decades in size) but reach a steady state. The corresponding cumulative normalized distribution is less steep