A biomathematical model of granulocytopoiesis for estimation of stem cell numbers.

In this paper a dynamic model of granulocytopoiesis is used to estimate stem cell numbers after acute and chronic irradiation. Regeneration data from irradiation accidents and bone marrow transplantation are investigated in the case of acute irradiation. Data from dogs living in a low-dose irradiation field are investigated for the case of chronic irradiation. The effects of acute irradiation and bone marrow transplantation are interpreted as a change of the initial conditions of the model, while the effect of chronic irradiation is interpreted as a continuous cell loss in the proliferating cell compartments of the model. The unknown initial conditions of the model are computed on the basis of real patient and dog data with the help of a suitably constructed optimization problem. The numerical solution of this optimization problem will only be sketched in this paper. In all cases discussed in this paper, a very good agreement between the model and the real data is achieved.