Fig. 3.

Alveolar nonhematopoietic cell-derived PGD₂ contributes to form a barrier in early-phase ALI, and leukocyte-derived PGD₂ autocrinely inhibits infiltration in later-phase ALI. (A–C) H-PGDS expression was detected in neutrophils (A), endothelial cells (B), and epithelial cells (C) on day 3 (n = 5–6 each). (Scale bar: 50 μm.) (D and E) After bone marrow transplantation, MPO activity was measured in WT (D) and H-PGDS^−/− (E) mice (n = 8 each). (F) Dye extravasation was monitored on day 1 (n = 8–10). (G–I) Female WT mice injected with male mouse-origin H-PGDS^−/− or WT neutrophils were subjected to LPS inhalation. (G) Y chromosomes were labeled in lung sections on day 3. (Scale bar: 50 μm.) (H) Number of Y chromosome-positive neutrophils in fields (n = 8 each). (I) MPO activity (n = 8 each). *P < 0.05 compared with WT+WT^BM (D and F), H-PGDS^−/− +H-PGDS^−/−BM (E), or WT+WT^NT (H and I).