Pasteurella haemolytica leukotoxin and endotoxin induced cytokine gene expression in bovine alveolar macrophages requires NF-kappaB activation and calcium elevation

摘要

The role of Ca2+ and tyrosine kinases in nuclear factor-kappaB (NF-kappaB) activation and expression of interleukin (IL)-1beta, tumour necrosis factoralpha and IL-8 genes in inflammatory and immune responses was investigated in bovine alveolar macrophages (BAMs). Bovine pulmonary artery endothelial cells and porcine alveolar macrophages were used to determine cellular and species-specificity of leukotoxin-induced Ca2+ elevation and NF-kappaB activation, respectively. It was concluded that NF-kappaBactivation in BAMs is a common mechanism underlying the effects of leukotoxins and lipopolysaccharides of P. haemolytica. The effects of leukotoxins on activation exhibited a high degree of cellular and species specificity. Expression of proinflammatorycytokine genes required Ca2+ elevation, but was differentially regulated by tyrosine-kinase dependent and -independent pathways in BAMs in response to leukotoxins and lipopolysaccharides.