Induction of interleukin-8 expression in porcine peripheral blood mononuclear cells by trans10– cis12 conjugated linoleic acid

The chemotaxis of porcine peripheral blood polymorphonuclear cells (PMN) was enhanced by culture supernatant from peripheral blood mononuclear cells (PBMC) treated with trans10– cis12 (10t–12c) conjugated linoleic acid (CLA) or by porcine recombinant (pr) interleukin (IL)-8. To identify this chemotactic inducing factor, the culture supernatant from 10t–12c CLA treated PBMC was partially purified by gel filtration. Only fraction 9 contained enhanced PMN chemotactic activity. The chemotactic activity of fraction 9 was inhibited by an anti-prIL-8 polyclonal antibody (pAb). Porcine IL-8 mRNA expression analyzed by a reverse transcriptase-polymerase chain reaction (RT-PCR) assay was increased in PBMC by the addition of 10t–12c CLA. This study strongly suggests that the immunoenhancing effect of CLA on the chemotactic response of porcine PMN is mediated through IL-8 produced by CLA treated PBMC.