title: In vivo depletion of CD8+ T lymphocytes abrogates protective immunity to African swine fever virus.
abstract: To understand the mechanisms involved in protective immunity to African swine fever virus (ASFV) infection, the observation that infection with the avirulent Portuguese ASFV isolate OUR/T88/3 protects outbred pigs from challenge with the virulent Portuguese ASFV isolate OUR/T88/1 was exploited. It was demonstrated that pigs exposed to OUR/T88/3 and then depleted of CD8+ lymphocytes were no longer fully protected from OUR/T88/1 challenge. This indicated that CD8+ lymphocytes play an important role in the protective immune response to ASFV infection and that anti-ASFV antibody alone, from OUR/T88/3 infection, was not sufficient to protect pigs from OUR/T88/1 challenge. Inbred pigs of the cc haplotype infected with OUR/T88/3 were not always protected from OUR/T88/1 challenge and developed both viraemia and fever. Such viraemia was always correlated with increased numbers of circulating CD8beta+ lymphocytes, indicating a specific role for CD8beta+ lymphocytes in combating viraemia. These experiments indicate an important role for CD8+ lymphocytes, particularly CD8beta+ lymphocytes, in ASF protective immunity.
authors.affiliation: Institute for Animal Health, Ash Road, Pirbright, Woking, Surrey GU24 0NF, UK.
authors.forename: C A L
authors.initials: CAL
authors.lastname: Oura
authors.affiliation: Institute for Animal Health, Ash Road, Pirbright, Woking, Surrey GU24 0NF, UK.
authors.forename: M S
authors.initials: MS
authors.lastname: Denyer
authors.affiliation: Institute for Animal Health, Ash Road, Pirbright, Woking, Surrey GU24 0NF, UK.
authors.forename: H
authors.initials: H
authors.lastname: Takamatsu
authors.affiliation: Institute for Animal Health, Ash Road, Pirbright, Woking, Surrey GU24 0NF, UK.
authors.forename: R M E
authors.initials: RME
authors.lastname: Parkhouse
mesh_terms: D000357:African Swine Fever / Q000276:immunology* / Q000517:prevention & control* / Q000821:virology; D000358:African Swine Fever Virus / Q000276:immunology / Q000472:pathogenicity*; D000818:Animals; D021461:Animals, Outbred Strains; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology*; D018655:Lymphocyte Count; D008212:Lymphocyte Depletion; D013552:Swine; D014766:Viremia / Q000276:immunology / Q000517:prevention & control / Q000821:virology