PMID- 23228653 OWN - NLM STAT- MEDLINE DCOM- 20130906 LR - 20130128 IS - 1873-2534 (Electronic) IS - 0165-2427 (Linking) VI - 151 IP - 3-4 DP - 2013 Feb 15 TI - Lymphocyte activation as cytokine gene expression and secretion is related to the porcine reproductive and respiratory syndrome virus (PRRSV) isolate after in vitro homologous and heterologous recall of peripheral blood mononuclear cells (PBMC) from pigs vaccinated and exposed to natural infection. PG - 193-206 LID - S0165-2427(12)00410-2 [pii] LID - 10.1016/j.vetimm.2012.11.006 [doi] AB - The present study evaluated the lymphocyte activation in PRRSV-vaccinated pigs subsequently exposed to natural infection by in vitro stimulation of peripheral blood mononuclear cells (PBMC) with homologous vaccine and two heterologous PRRSV isolates. The responsiveness was assessed by determining IFN-gamma secreting cells by ELISpot assay, lymphocyte CD8 phenotype by intracellular staining/flow cytometry, cytokine gene expression by real-time quantitative PCR and cytokine secretion by ELISA. Conventional pigs were weaned at 28 days of age and inoculated intramuscularly (IM) or needle-less intradermally (ID) with a modified-live PRRSV vaccine suspended in adjuvant, while control pigs were injected with adjuvant alone (ADJ). Blood samples were collected at vaccination, 35 days post-vaccination and after 35 days post-exposure to natural infection by a heterologous field strain. Thirty-five days post-vaccination, PRRSV vaccine induced a low but significant virus-specific IFN-gamma secreting cell response upon stimulation with both the vaccine strain and the two isolates in vaccinated pigs. Conversely, after 35 days post-exposure, only the vaccine strain and the BS/114/S isolate triggered this response. Intracellular staining showed that PRRSV-specific immune cells reacting upon vaccine strain and BS/114/S stimulation were mostly CD8(+) IFN-gamma producing cells whereas the stimulation with BS/55 isolate induced an IFN-gamma production associated to the CD8(-)IFN-gamma(+) phenotype. At 35 days post-vaccination, PBMC from vaccinated pigs showed lower IL-10 expression and release, and higher TNF-alpha gene expression upon stimulation with both the vaccine and viral isolates. After infection, both cytokines were not differently modulated in different groups. Immune parameters give evidence that IFN-gamma secreting cells in the peripheral blood can be elicited upon PRRSV infection although vaccination itself does not stimulate high levels of these reactive cells. Moreover, the cross-reactivity against divergent PRRS viruses can show a different intensity and be differently associated with cytotoxic CD8(+)IFN-gamma(+) as well as CD8(-)IFN-gamma(+) cells. Overall, the obtained data confirmed that the immune activation against PRRSV is not dependent on the genetic divergence of the virus. Especially after infection, a different immune reactivity was evident upon stimulation with the different isolates in terms of frequency and CD8 phenotype of PRRSV-specific IFN-gamma producing cells. The modulation of cytokines in vaccinated pigs appeared to be more dependent on vaccination or infection conditions than on stimulation by different isolates, and the changes of IL-10 more relevant than those of TNF-alpha at gene and protein levels. Moreover, under the conditions of this study, the PRRSV vaccine administered via the intradermal route by a needle-less device was confirmed to induce an immune response comparable or in some cases higher than the intramuscular route. CI - Copyright (c) 2012 Elsevier B.V. All rights reserved. FAU - Ferrari, Luca AU - Ferrari L AD - Department of Veterinary Sciences, University of Parma, Via del Taglio, 10 - 43126 Parma, Italy. luca.ferrari@unipr.it FAU - Martelli, Paolo AU - Martelli P FAU - Saleri, Roberta AU - Saleri R FAU - De Angelis, Elena AU - De Angelis E FAU - Cavalli, Valeria AU - Cavalli V FAU - Bresaola, Marcello AU - Bresaola M FAU - Benetti, Michele AU - Benetti M FAU - Borghetti, Paolo AU - Borghetti P LA - eng PT - Journal Article PT - Research Support, Non-U.S. Gov't DEP - 20121119 PL - Netherlands TA - Vet Immunol Immunopathol JT - Veterinary immunology and immunopathology JID - 8002006 RN - 0 (Antibodies, Neutralizing) RN - 0 (Antibodies, Viral) RN - 0 (Cytokines) RN - 0 (Tumor Necrosis Factor-alpha) RN - 0 (Viral Vaccines) RN - 130068-27-8 (Interleukin-10) RN - 82115-62-6 (Interferon-gamma) SB - IM MH - Animals MH - Antibodies, Neutralizing/blood MH - Antibodies, Viral/blood MH - Antibody Specificity MH - CD8-Positive T-Lymphocytes/immunology MH - Cross Reactions MH - Cytokines/*biosynthesis/*genetics MH - Gene Expression MH - Immunity, Cellular MH - Injections, Jet MH - Interferon-gamma/biosynthesis MH - Interleukin-10/biosynthesis/genetics MH - *Lymphocyte Activation MH - Porcine Reproductive and Respiratory Syndrome/immunology/prevention & control MH - Porcine respiratory and reproductive syndrome virus/*immunology MH - Sus scrofa/genetics/*immunology/*virology MH - Swine MH - Tumor Necrosis Factor-alpha/biosynthesis/genetics MH - Vaccination/methods/veterinary MH - Viral Vaccines/administration & dosage/immunology EDAT- 2012/12/12 06:00 MHDA- 2013/09/07 06:00 CRDT- 2012/12/12 06:00 PHST- 2012/09/20 00:00 [received] PHST- 2012/11/09 00:00 [revised] PHST- 2012/11/12 00:00 [accepted] PHST- 2012/12/12 06:00 [entrez] PHST- 2012/12/12 06:00 [pubmed] PHST- 2013/09/07 06:00 [medline] AID - S0165-2427(12)00410-2 [pii] AID - 10.1016/j.vetimm.2012.11.006 [doi] PST - ppublish SO - Vet Immunol Immunopathol. 2013 Feb 15;151(3-4):193-206. doi: 10.1016/j.vetimm.2012.11.006. Epub 2012 Nov 19.