In vitro inhibition of 5-lipoxygenase metabolite, leukotriene B4, in bovine mononuclear cells by bovine viral diarrhea virus.

Bovine viral diarrhea (BVD) virus inhibited phytohemagglutinin (PHA)-, PHA plus phorbol-12-myristate-13 acetate (PMA)- or PHA plus calcium ionophore (A23187)-stimulated bovine peripheral blood mononuclear cell (PBMC) proliferation. Further, BVD-virus inhibited A23187-stimulated leukotriene B4 (LTB4) synthesis into the culture supernatants. Presence of exogenous LTB4 failed to reverse the BVD virus-induced immunosuppression. Our results suggest that BVD virus-induced immunosuppression is due to a factor that may be necessary to induce LTB4 synthesis for normal mononuclear cell proliferation.