GMPs and CMoPs proliferate rapidly immediately following Mpc2 deletion. (A) Schematic representation of BrdU pulse experiment using Mpc2 mixed bone marrow chimeras. Chimeric mice were injected with BrdU 1 h prior to sacrifice. (B) Representative histograms of BrdU staining in GMPs of Mpc2 control, recent KO, and prolonged KO chimeras. Gray lines represent staining of GMPs from a mouse that was not injected with BrdU. Blue and red lines represent CD45.1⁺ (WT) and CD45.2⁺ (WT, recent KO, or prolonged KO) GMPs respectively from the same mouse injected with BrdU. (C) BrdU incorporation was measured in both CD45.1⁺ (WT) and CD45.2⁺ (WT, recent Mpc2 deletion, or prolonged Mpc2 deletion) CMPs, GMPs, and CMoPs following a 1-h pulse of BrdU. Each line connects CD45.1⁺ and CD45.2⁺ cells within the same mouse (n = 11 for WT chimeras and n = 19 for recent and prolonged KO chimeras). Data are pooled from two independent experiments. ****, P < 0.0001 by paired two-way ANOVA with post-hoc Sidak’s multiple comparisons test. (D) Schematic representation of BrdU pulse-chase experiment using Mpc2 mixed bone marrow chimeras to assess survival and turnover. Chimeras were administered BrdU water for 1 wk and then were switched back to normal drinking water, at which point BrdU incorporation was assessed in peripheral blood at the time of removal from BrdU and three successive days afterwards. (E) BrdU incorporation was measured in peripheral CD45.2⁺ Ly6C^hi monocytes and neutrophils following a 3-d chase after a week of BrdU water administration. Mean values ± SEM are shown. Data are pooled from two independent experiments. P values >0.05 by two-way ANOVA with post-hoc Tukey’s multiple comparisons test are not depicted.