Molecular cloning and expression of bovine interleukin-8.
Interleukin-8 (IL-8) is a neutrophil and T-lymphocyte chemotactic and activating factor. This cytokine is produced by many cell types including macrophages in response to a variety of microbial and non-microbial agents. In the present study, we determined the nucleotide sequence for bovine IL-8 cDNA. The amino acid sequence encoded by this cDNA shares 76 and 87% homology with the human and swine IL-8 proteins, respectively. Bovine IL-8 cDNA was expressed in Escherichia coli as a beta-galactosidase fusion protein. Western blotting demonstrates that this fusion protein, but not beta-galactosidase cross-reacts with monospecific anti-human IL-8 antiserum. We also studied the induction of IL-8 mRNA synthesis in bovine alveolar macrophages (BAM) stimulated with heat-killed Pasteurella haemolytica. IL-8 mRNA was induced in BAM as early as 1 h and was detectable at high levels 12 h post-stimulation with P. haemolytica. A dose titration of P. haemolytica and E. coli endotoxins showed that a relatively low level of P. haemolytica endotoxin induced high levels of bovine IL-8 mRNA. The significance of these findings in the pathogenesis of bovine pneumonia caused by P. haemolytica is discussed.
Morsey
M A
MA
Veterinary Infectious Disease Organization, Saskatoon, Canada.
Popowych
Y
Y
Kowalski
J
J
Gerlach
G
G
Godson
D
D
Campos
M
M
Babiuk
L A
LA
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002417:Cattle; D002478:Cells, Cultured; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics; D004731:Endotoxins / Q000494:pharmacology; D004926:Escherichia coli / Q000235:genetics; D005786:Gene Expression Regulation / Q000187:drug effects; D006801:Humans; D016209:Interleukin-8 / Q000096:biosynthesis* / Q000737:chemistry / Q000235:genetics*; D016676:Macrophages, Alveolar; D016978:Mannheimia haemolytica; D008969:Molecular Sequence Data; D012333:RNA, Messenger / Q000096:biosynthesis; D011993:Recombinant Fusion Proteins; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid
D018076:DNA, Complementary; D004731:Endotoxins; D016209:Interleukin-8; D012333:RNA, Messenger; D011993:Recombinant Fusion Proteins