Cell-intrinsic requirement of GM-CSF for the development of alveolar macrophages.

<p>(A) Identification of live (eFluor780⁻) AM (CD45⁺CD11c⁺Siglec-F⁺ autofluorescent^high) in BAL and lung of WT and <i>Csf2</i>^−/− mice. (B) Absolute cell numbers of AM. (C) Quantification of dead CD45⁻eFluor780⁺ cells in the BAL. (D) Efferocytosis of i.t. instilled apoptotic thymocytes by indicated populations of myeloid cells. Values shown depict percentages of efferocytic cells. (E and F) Concentrations of total protein (E) and palmitic acid (F) were measured in the BAL of WT and <i>Csf2</i>^−/− mice. (G) Panels show H&E-stained histological lung sections of WT and <i>Csf2</i>^−/− mice. (H) Absolute cell numbers of neutrophils (CD11b⁺CD11c⁻Gr-1⁺) in the BAL. (I) Arterial oxygen saturation in WT and <i>Csf2</i>^−/− mice. (J and K) Mixed BM chimeras (1∶1 mixture of CD45.1⁺WT∶CD45.2⁺<i>Csf2rb</i>^−/− or CD45.1⁺WT∶CD45.2⁺WT) were analyzed for the contribution of CD45.1 and CD45.2 BM to the development of AM. (J) Dot plots show the percentage of CD45.1⁺WT and CD45.2⁺<i>Csf2rb</i>^−/− (or control CD45.2⁺WT) cells among CD11c⁺Siglec-F⁺ AM in the BAL and lung. (K) Bar graphs display the frequency of CD45.2⁺WT and CD45.2⁺<i>Csf2rb</i>^−/− AM as gated in (J). The mean ± SD is shown.