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.


METHODS
Mac-T cells and E coli from cows with mastitis.


METHODS
Mac-T cells were incubated with E coli or its products. The cytokine response of Mac-T cells to these treatments was quantified by measuring mRNA content of interleukin (IL)-1alpha, IL-1beta, IL-8, and tumor necrosis factor (TNF)-alpha by use of a quantitative reverse transcriptase-polymerase chain reaction assay. The amount of TNF-alpha secreted was also measured.


RESULTS
Treatment with E coli or its products resulted in significant increases in IL-1alpha, IL-8, and TNF-alpha mRNA content in Mac-T cells. This increase was reversible when culture filtrate was incubated with polymyxin B. The amount of IL-1beta mRNA in Mac-T cells increased only slightly over baseline after treatment with E coli or its products, but this increase was not diminished by incubation of E coli filtrate with polymyxin B.


CONCLUSIONS
Incubation of Mac-T cells with E coli or its products resulted in increased amounts of IL1alpha, IL-8, and TNF-alpha mRNA. Inhibition of this response by incubation of culture filtrate with polymyxin B suggested that lipopolysaccharide was the main bacterial product that stimulated the cytokine response. The small increase in IL-1beta content in Mac-T cells incubated with E coli or its products suggested that this cytokine had a smaller role in the Mac-T cell response to E coli.
McClenahan
David J
DJ
Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin, Madison, WI 53706, USA.
Sotos
Josh P
JP
Czuprynski
Charles J
CJ
D000818:Animals; D002417:Cattle; D002460:Cell Line; D003470:Culture Media / Q000633:toxicity; D016207:Cytokines / Q000276:immunology / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D004847:Epithelial Cells / Q000187:drug effects / Q000276:immunology*; D004926:Escherichia coli / Q000276:immunology / Q000472:pathogenicity; D005260:Female; D007375:Interleukin-1 / Q000276:immunology; D016209:Interleukin-8 / Q000276:immunology; D008070:Lipopolysaccharides / Q000276:immunology / Q000633:toxicity; D008321:Mammary Glands, Animal / Q000166:cytology*; D008414:Mastitis, Bovine / Q000276:immunology*; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000662:veterinary; D014409:Tumor Necrosis Factor-alpha / Q000276:immunology
D003470:Culture Media; D016207:Cytokines; D007375:Interleukin-1; D016209:Interleukin-8; D008070:Lipopolysaccharides; D014409:Tumor Necrosis Factor-alpha