The role of leukocytes in the pathogenesis of fibrin deposition in bovine acute lung injury.

摘要: The peculiarly fibrinous nature of bovine acute lung injury due to infection with Pasteurella haemolytica A1 suggests an imbalance between leukocyte-directed procoagulant and profibrinolytic influences in the inflamed lung. Calves experimental pneumonia produced by intratracheal inoculation P. developed locally extensive cranioventral fibrinopurulent bronchopneumonia. Pulmonary alveolar macrophages (PAM) recovered segmental lavage from affected lobes were 30 times more than PAM obtained unaffected 37-fold control calf lungs. Unlike enhancement activity, activity (plasminogen activator amidolysis) total leukocytes (PAM plasminogen neutrophils [PMN]) was decreased 23 cells also four infected animals. This marked cellular fibrinolytic probably contributes significantly enhanced fibrin deposition retarded removal. In addition, lungs strongly positive for tissue factor antigen as demonstrated immunocytochemistry. Intensely factor-positive enmeshed fibrinocellular exudates walls situated such that they likely have, concert, initiated extrinsic activation coagulation acutely These data collectively suggest PAM-directed diminished PAM- PMN-directed represent important modifications local leukocyte function are central pathogenesis lesion development