Fig. 1. Hepcidin reduces systemic neutrophil numbers.

(A) Predicted absolute number of iron atoms in total and grouped by pathway, as well as percentage of detected proteins that are iron-interacting proteins in resting human peripheral blood leukocytes. Means ± SD. mDC, myeloid dendritic cell; pDC, plasmacytoid dendritic cell; FA, fatty acid. (B) Predicted iron requirements (in milligrams per day) for hematopoietic production of the specified lineage, compared to literature-derived value for red blood cell (RBC) production. (C) Experiment scheme to test effect of mHep on hematopoiesis. i.p., intraperitoneally. (D) Number of splenic myeloid subsets in experiment described in (C). Representative of three independent replicates. Neutrophils and eosinophils, Mann-Whitney test; monocytes, unpaired t test. Means ± SD. (E) Blood myeloid subsets (numbers per microliter) in experiment described in (C). Representative of three independent replicates. Neutrophils, Welch’s unpaired t test; eosinophils and monocytes, unpaired t test. Means ± SD. (F) Numbers of mature neutrophils and eosinophils in the bone marrow (BM) in the experiment described in (C). Representative of three independent replicates. Unpaired t test. Means ± SD. (G) Numbers of mature monocytes in the BM in experiment described in (C). Representative to three independent replicates. Unpaired t test. Means ± SD. (H) Numbers of committed granulocyte progenitors and committed monocyte progenitors (cMoPs) in experiment described in (C). Representative of three independent replicates. Unpaired t test. Means ± SD. (I) Comparison of CD71 expression between myeloblasts (granulocyte progenitors) and cMoPs in experiment described in (C). Paired t test. Effect of mHep treatment on CD71 expression by myeloblasts and cMoPs. Unpaired t test. Means ± SD. MFI, median fluorescence intensity. (J) Graphical summary of changes in cell numbers observed after mHep treatment. NK, natural killer.