 Tissue factor TF-dependent procoagulant activity and associated inflammatory processes may play a role in the severity and progression of ALIARDS. Recent studies demonstrated that TF levels were elevated in plasma and pulmonary edema fluid of ARDSALI patients compared to control patients with hydrostatic pulmonary edema. These higher plasma TF levels were correlated with increased mortality, fewer ventilation-free days, the presence of disseminated intravascular coagulation and the presence of sepsis in patients with ALIARDS, suggesting that systemic activation of coagulation may be clinically important in ALIARDS. Moreover, the pulmonary TF levels in patients with ALIARDS were found to range between 0.5 and 2 nM, approximately 100-fold higher than simultaneous plasma levels, suggesting an intra-alveolar source of TF. Thus, anti-TF antibody blockage of TF activity may therefore provide an effective therapeutic mechanism for the treatment of inflammatory disorders such as ALI and ARDS. This study will test the hypothesis that administration of anti-TF antibody ALT-836 to septic patients with ALIARDS will improve the clinical outcome by shortening the duration of mechanical ventilation for these patients. 