Dynamin-2-dependent targeting of mannheimia haemolytica leukotoxin to mitochondrial cyclophilin D in bovine lymphoblastoid cells.

Exotoxins which belong to the family containing the RTX toxins (repeats in toxin) contribute to a variety of important human and animal diseases. One example of such a toxin is the potent leukotoxin (LKT) produced by the bovine respiratory pathogen Mannheimia haemolytica. LKT binds to CD18, resulting in the death of bovine leukocytes.

Cytokine response of bovine mammary gland epithelial cells to Escherichia coli, coliform culture filtrate, or lipopolysaccharide.

Objective: To define the cytokine response of a cultured mammary gland epithelial cell line (ie, Mac-T) when incubated with Escherichia coli or its products.

Sample Population: Mac-T cells and E coli from cows with mastitis.

Procedure: Mac-T cells were incubated with E coli or its products.

In vitro evaluation of the role of platelet-activating factor and interleukin-8 in Mannheimia haemolytica-induced bovine pulmonary endothelial cell injury.

Objective: To develop an in vitro model of the bovine alveolar-capillary interface and to evaluate the roles of interleukin-8 (IL-8) and platelet-activating factor (PAF) in neutrophil-mediated endothelial injury induced by infection with Mannheimia haemolytica.

Sample Population: Cultured bovine pulmonary microvascular endothelial cells, freshly isolated bovine neutrophils, and monocyte-derived bovine macrophages.

Procedure: A coculture system was developed in which endothelial cells were grown to confluence in tissue culture inserts, neutrophils were added to the inserts, and macrophages were added to tissue culture wells.