AFRICAN SWINE FEVER VIRUS-SPECIFIC CYTOTOXIC T-LYMPHOCYTES RECOGNIZE THE 32 KDA IMMEDIATE-EARLY PROTEIN (VP32)

African swine fever (ASF) virus-specific cytotoxic T lymphocyte (CTL) activity has been studied in a model in which SLA inbred minipigs were experimentally infected with an attenuated isolate of the virus. The CTL assays were performed using alveolar macrophages as target cells. The specific lysis is mediated by purified CD8(+) lymphocytes but not by CD4(+) cells and can be blocked by incubation with anti-SLA class I monoclonal antibodies. The purified CD8(+) population produced high l evels of interferon-gamma after ASF virus stimulation. In an attempt t o define the Viral proteins recognized by CTL, target cells infected w ith a recombinant vaccinia virus (VV) expressing the ASF virus p32, an immediate early protein during ASF virus replication, were recognized and lysed by CTL. This assay may be useful for VV recombinant screeni ng in order to identify other potential target ASF virus proteins. (C) 1997 Elsevier Science B.V.