INTERFERON-ALPHA PRODUCTION AND TISSUE LOCALIZATION OF INTERFERON-ALPHA BETA PRODUCING CELLS AFTER INTRADERMAL ADMINISTRATION OF AUJESZKYS-DISEASE VIRUS-INFECTED CELLS IN PIGS/

Intradermal administration of glutaraldehyde-fixed Aujeszky's disease virus (ADV) infected autologous or allogeneic cells resulted in the in duction of an interferon(IFN)-alpha response in pigs. Using a sensitiv e dissociation-enhanced lanthanide fluoroimmunoassay (DELFIA), IFN-alp ha was detected in blood at 8 and 24 h after injection of ADV-infected cells. In parallel, by means of in situ hybridization, IFN-alpha/beta mRNA containing cells were demonstrated in regional lymph nodes. Occa sional IFN-alpha/beta mRNA positive cells were also seen in injected d ermal areas, but not in contralateral lymph nodes, spleen, bone marrow , blood or liver. The ability of leucocytes in whole blood cultures to produce IFN-alpha upon stimulation by ADV was markedly diminished 3-7 days after intradermal injection of ADV-infected cells. In contrast, cultures of purified peripheral blood mononuclear cells (PBMC) had int act IFN-alpha responses. Further, serum from ADV-injected pigs inhibit ed the in vitro ADV-induced IFN-alpha responses in PBMC from control p igs, most likely due to the demonstrated presence of anti-ADV antibodi es. We suggest that the IFN-alpha/beta producing cells in lymph nodes may participate in the development of antiviral immunity and could be equivalent to Natural IFN-alpha/beta producing (NIP) cells.