Model for the total blood granulocyte pool (TBCG) in normal subjects. CGP indicates circulating granulocyte pool; MGP, marginal granulocyte pool; and BM, bone marrow. Illustration by Kenneth Probst. This research was originally published in Blood. Cartwright GE, Athens JW, Wintrobe MM. The kinetics of granulopoiesis in normal man. Blood. 1964;24:780-803. ©American Society of Hematology.¹⁶