Effects of a neutralizing PSGL-1 (P-selectin glycoprotein ligand 1) antibody on ventilator-induced lung injury (VILI) and LPS-induced murine lung inflammation. When compared with spontaneously breathing control mice (Veh), exposure to VILI (40 ml/kg, 4 h) or LPS (1 mg/kg, 18 h) in C57/B6 mice produces robust increases in (A and C) total BAL protein levels and (B and D) total BAL cell counts. (A and B) In vivo PSGL-1 inhibition with a neutralizing antibody, CD162 (intravenous injection, 1 mg/kg) attenuates LPS-mediated lung injury. Compared with mice treated with phosphate-buffered saline vehicle, PSGL-1 antibody–pretreated mice had significant reductions in BAL total protein levels (A) and BAL total cell counts (B) when exposed to LPS-induced lung injury. (C and D) In vivo PSGL-1 inhibition attenuates VILI with significant reductions in BAL total protein levels (C) and BAL total cell counts (D). These studies confirm that PSGL-1 contributes to VILI and LPS-induced lung injury and pathobiology. Results are expressed as mean (±SEM); n = 3–5 per condition; *P < 0.01. Ab = antibody.