A BIOASSAY FOR BOVINE INTERLEUKIN-1 BY THE A375 CELL-GROWTH INHIBITION

Usefulness of a human melanoma cell line A375 was evaluated for detect ing bovine interleukin-1 (IL-1). The A375 cell growth was inhibited by culture supermatant of lipopolysaccharide-stimulated bovine periphera l blood mononuclear cells (LPSsup) in a dose dependent manner. A mixtu re of anti-human IL-1 alpha and beta antibodies suppressed 60% of this inhibitory activity and was confirmed to bind to about 23 k dalton pe ptides in the LPSsup by Western blotting. Although serum and bronchoal veolar lavage fluid from a healthy cow showed a low inhibitory activit y, those from pneumonic cows showed the higher activities. These activ ities were also suppressed by anti- human IL-1 antibodies. These findi ngs show the A375 cell growth inhibition assay can be a useful bioassa y for bovine IL-1 (like) activity.