Fig. 3. Bone marrow erythropoiesis in Pax8^-/- and TR^0/0 mutants. (A) Bone marrow cellularity in Pax8^-/-, TH-treated Pax8^-/- mice, TR^0/0 mice and respective controls. Bone marrow nucleated cells obtained from 15-day-old mice were counted and cell numbers plotted as a cellularity index (n=3 for each genotype). (B) Analysis of resident BM populations in Pax8^-/- mice (n=3 except for Pax8^-/-, where n=2). (C) Distribution of the various erythrocytic cell subpopulations in the bone marrow of Pax8^-/- and TR^0/0 mice. Due to the different genetic backgrounds, each mutant was compared with its appropriate control littermate in the same column. Bone marrow cells obtained from 15-day-old mice were analyzed by FACS using the anti-CD71 and anti-TER1119 antibodies to distinguish the different developmental stages of erythroblast maturation (stages I to IV). Percentages of each subset are indicated in the gates. Dead cells and enucleated red blood cells (with low forward scatter) were excluded from FACS analysis. One representative example, out of four, is shown here.