RÉSUMÉ
A preliminary study into the protective mechanisms of adaptive immunity against porcine reproductive and respiratory syndrome virus (PRRSV) in piglets (n = 9) born to a gilt challenged intranasally with a type-2 PRRSV. Immune parameters (neutralizing antibodies, CD3⁺CD4⁺, CD3⁺CD8⁺, CD3⁺CD4⁺CD8⁺ T-lymphocytes, and PRRSV-specific interferon (IFN)-γ secreting T-lymphocytes) were compared with infection parameters (macro- and microscopic lung lesion, and PRRSV-infected porcine alveolar macrophages (CD172α⁺PRRSV-N⁺ PAM) as well as with plasma and lymphoid tissue viral loads. Percentages of three T-lymphocyte phenotypes in 14-days post-birth (dpb) peripheral blood mononuclear cell (PBMC) had significant negative correlations with percentages of CD172α⁺PRRSV-N⁺ PAM (p 0.1) with infection parameters. The results indicate that T-lymphocytes contribute to controlling PRRSV replication in young piglets born after in-utero infection.
Sujet(s)
Immunité acquise , Anticorps , Anticorps neutralisants , Interférons , Poumon , Noeuds lymphatiques , Tissu lymphoïde , Macrophages alvéolaires , Phénotype , Plasma sanguin , Syndrome dysgénésique et respiratoire porcin , Virus du syndrome respiratoire et reproducteur porcin , Lymphocytes T , Charge viraleRÉSUMÉ
A preliminary study into the protective mechanisms of adaptive immunity against porcine reproductive and respiratory syndrome virus (PRRSV) in piglets (n = 9) born to a gilt challenged intranasally with a type-2 PRRSV. Immune parameters (neutralizing antibodies, CD3âºCD4âº, CD3âºCD8âº, CD3âºCD4âºCD8⺠T-lymphocytes, and PRRSV-specific interferon (IFN)-γ secreting T-lymphocytes) were compared with infection parameters (macro- and microscopic lung lesion, and PRRSV-infected porcine alveolar macrophages (CD172αâºPRRSV-N⺠PAM) as well as with plasma and lymphoid tissue viral loads. Percentages of three T-lymphocyte phenotypes in 14-days post-birth (dpb) peripheral blood mononuclear cell (PBMC) had significant negative correlations with percentages of CD172αâºPRRSV-N⺠PAM (p 0.1) with infection parameters. The results indicate that T-lymphocytes contribute to controlling PRRSV replication in young piglets born after in-utero infection.