Download or read book Cell mediated Immunity in Porcine Reproductive and Respiratory Syndrome Virus written by Rajeshwari Parida and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Cell mediated Immunity to Porcine Reproductive and Respiratory Syndrome Virus in Swine written by Elida Margoth Bautista and published by . This book was released on 1998 with total page 564 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Cell mediated Immune Response to Porcine Reproductive and Respiratory Syndrome Virus written by Wasin Charerntantanakul and published by . This book was released on 2006 with total page 284 pages. Available in PDF, EPUB and Kindle. Book excerpt: The cell-mediated immune (CMI) response of pigs to porcine reproductive and respiratory syndrome virus (PRRSV) is low in magnitude and appears late after infection. The ability of PRRSV to suppress CMI response is not known. We reported in this dissertation that PRRSV has the ability to significantly suppress CD25, interferon gamma (IFN[Gamma]), and tumor-necrosis factor alpha expression by T cells in response to concanavalin A and phorbol 12-myristate 13-acetate plus ionomycin, respectively. The suppressive ability of PRRSV associated with PRRSV virulence and type of myeloid antigen-presenting cells the virus infect. Virulent PRRSV significantly suppressed T cell response, whereas attenuated PRRSV did not. Monocytes supported T cell suppression more effectively than monocyte-derived macrophages and immature monocyte-derived dendritic cells. T cell suppression negatively associated with increased interleukin-10 (IL-10) gene expression. Neutralization of IL-10 activity by anti-swine IL-10 monoclonal antibodies inhibited T cell suppression. PRRSV modified-live virus (MLV) vaccine is currently used in the field to control diseases caused by PRRSV. To enhance CMI response to PRRSV MLV vaccine, five different vaccine adjuvants (bacterial endotoxin-derived adjuvant, mixed open reading frame 5 (ORF5) peptides derived from 5 PRRSV isolates, porcine IFN[Alpha], polyinosinic-polycytidylic acid stabilized with polylysine and carboxymethylcellulose, and porcine IL-12) were studied. Administration of mixed 0RF5 peptides at 14 and 28 days after PRRS MLV vaccination significantly increased IFN[Gamma] production in CD4−CD8+[Gamma Delta]+, CD4−CD8+[Gamma Delta]+, and CD4−CD8+[Gamma Delta]− T cells. Administration of porcine IL-12 at 1 day after PRRS MLV vaccination significantly increased IFN[Gamma] production in CD4+CD8+[Gamma Delta]−, CD4−CD8+[Gamma Delta]+, and CD4−CD8+[Gamma Delta]− T cells. Significantly increased IFN[Gamma] expression in CD4+CD8+[Gamma Delta]−, CD4−CD8+[Gamma Delta]+, and CD4−CD8+[Gamma Delta]− T cells but not CD4−CD8+[Gamma Delta]+ T cells were correlated significantly with the reduction of lung lesion scores and viremia after virulent PRRSV challenge. Administration of porcine IFN[Alpha] at -1, 0, and 1 day and porcine IL-12 at 1 day after PRRS MLV vaccination significantly increased CD25 expression in CD4−CD8+[Gamma Delta]+ T cells. However, the increased CD25 expression did not correlate with protection. None of the vaccine adjuvants contributed to the reduction of lung lesion scores and viremia in comparison to PRRS MLV alone.

Download or read book Investigation of Immune Response and Protection Induced by a Combined Vaccination of Modified Live and Killed Porcine Reproductive and Respiratory Syndrome Virus Vaccines and Its Potential Use in a Swine Herd written by Dachrit Nilubol and published by . This book was released on 2004 with total page 280 pages. Available in PDF, EPUB and Kindle. Book excerpt: Commercially modified live (MLV) and killed (KV) porcine reproductive and respiratory syndrome virus (PRRSV) vaccines induce slow development of effective immunity as measured by serum neutralizing (SN) antibody and cell-mediated immunity. The objective of the studies was to develop more effective vaccines or vaccination strategies based on commercial vaccines. The immune response and produced induced were characterized. Three separate studies were conducted to investigate the efficacy of vaccination protocols including vaccination with MLV and KV, either alone or in combination, KV with interleukin (IL)-12 added, and KV used as a booster vaccine in a PRRSV positive herd. The protection induced was also evaluated by challenging pigs with PRRSV. It was found that the MLV followed by KV induced significantly higher SN antibody levels compared to either vaccine alone. This vaccination protocol significantly reduced serum viral RNA, severity of lung lesion, and clinical disease. In contrast, the addition of IL-12 did little to enhance the efficacy of the KV although clinical respiratory disease consistent with PRRSV following challenge was significantly reduced; however, no reduction of viral RNA in serum or reduced persistence of virus in tonsils or BAL was observed. The KV administration of gestational sows significantly increased SN antibodies in serum and colostrum at farrowing and at weaning compared to non-vaccinated sows. Furthermore, pigs farrowed from the vaccinated sows had significantly higher levels of maternally derived antibodies (MDA) as measured by both SN and ELISA assays than pigs farrowed from the non-vaccinated sows. Pigs farrowed from vaccinated sows and challenged at 10 days of age displayed the mildest clinical disease and had lower levels of serum viral RNA than pigs from non-vaccinated sows. Incomplete reduction of serum viral RNA and lung lesion suggests incomplete protection provided by MDA. The present studies provide useful information to the swine industry as a combination vaccination protocol, MLV followed by KV, could be used to in the reduction of clinical disease and viremia. In addition, KV can be used as a booster vaccine to enhance the existing immunity of sows in a PRRSV positive herd resulting in enhanced MDA in piglets.

Download or read book Development and Evaluation of Efficacy of Novel Porcine Reproductive and Respiratory Syndrome PRRS Virus Vaccine Candidates in Pigs written by Yashavanth Shaan Lakshmanappa and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Further, PRRSV MLVs have a safety concern, however killed vaccines are safe but have an efficacy concern due to their less immunogenicity. In that study, we employed killed vaccines against PRRSV-1 and PRRSV-2 species along with a potent mucosal adjuvant, like non-toxic heat labile (LT) enterotoxin for priming, followed by oral boosting with immunogenic conserved T-cell epitopes of PRRSV expressed by non-pathogenic E. coli against respective homologous challenge virus infections in pigs. We showed that our vaccination strategy induced a robust cell-mediated immune response, especially T cell responses against both PRRSV-1 and PRRSV-2, and improved the overall adaptive immune response in pigs. Further studies are needed to improve the PRRSV specific B-cell response and in turn enhance the virus neutralizing antibody titers against both the PRRSV species.

Download or read book Cross reactive Immunity to Porcine Reproductive and Respiratory Syndrome Virus and Its Contribution to Protection written by Ignacio Correas and published by . This book was released on 2017 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Due to the vast geographical distribution and significant economic losses generated, porcine reproductive and respiratory syndrome virus (PRRSV) can be considered the most important swine pathogen of contemporary times. Current control and eradication strategies against PRRSV have difficulty succeeding because of their complex nature and the absence of an effective vaccine. A major obstacle for PRRSV vaccine development is the broad heterogeneity of the virus, both at the genetic and antigenic level, its rapid evolution, and an incomplete knowledge of the immune responses responsible for clearing the virus from the host. Specifically, how known correlates of protection against PRRSV---neutralizing antibodies and T cells---cross-react with heterologous isolates and mediate cross-protection is inadequately understood. The objectives of this dissertation were (i) to determine the extent of cross-reactivity of immune responses against PRRSV, and (ii) to ascertain how cross-reactive immune responses mediate protection against heterologous isolates. T cell responses were found to be cross-reactive among PRRSV-2 isolates, but extremely variable among individual animals, while the neutralizing antibody response induced by a single infection with PRRSV was deemed to be solely self-neutralizing. Sequential exposure to heterologous PRRSV-2 isolates elicited neutralizing antibodies to the isolates used for infection and challenge, as well as other heterologous PRRSV-2 isolates. Furthermore, prior exposure to PRRSV afforded cross-protection against heterologous challenge, with reduction in viremia, tissue viral load and the extent of microscopic lung lesions; however, protection was still suboptimal. T cell cross-reactivity between PRRSV-1 and PRRSV-2 was evaluated at the structural protein level and was deemed to be feeble or absent. Prior exposure to PRRSV-1 did not prime the T cell response against the PRRSV-2 structural proteins after PRRSV-2 challenge. Collectively, the results in this dissertation contribute to furthering the understanding of immune responses against PRRSV and may be used in the development of a better vaccine.

Download or read book Veterinary Vaccines written by R. Pandey and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 354 pages. Available in PDF, EPUB and Kindle. Book excerpt: Vaccines have historically been considered to be the most cost-effective method for preventing communicable diseases. It was a vaccine that enabled global eradication of the dreaded disease smallpox. Mass immunization of children forms the anchor of the strategy of the World Health Organization (WHO) to attain "health for all" status by the year 2000. Vaccinology is undergoing a dimensional change with the advances that have taken place in immunology and genetic engineering. Vaccines that confer short or inadequate immunity or that have side effects are being replaced by better vaccines. New vaccines are being developed for a variety of maladies. Monoclonal antibodies and T cell clones have been employed to delineate the immunodeterminants on microbes, an approach elegantly complemented by computer graphics and molecular imaging techniques. Possibilities have opened for obtaining hitherto scarce antigens of parasites by the DNA recombinant route. Better appreciation of the idiotypic network has aroused research on anti idiotypic vaccines. Solid-phase synthesis of peptides is leading to an array of synthetic vaccines, an approach that is expected to attain its full potential once the sequences activating suppressor cells are discovered and the rules for presentation of antigens to T and B cells are better worked out. A new breed of vaccines is on the horizon that seeks to control fertility. Originally conceived to intercept a step in the reproductive process, they are conceptual models for developing approaches to regulate the body's internal processes.

Download or read book Veterinary Vaccines written by Samia Metwally and published by John Wiley & Sons. This book was released on 2021-04-01 with total page 350 pages. Available in PDF, EPUB and Kindle. Book excerpt: Provides a concise and authoritative reference on the use of vaccines against diseases of livestock Compiled by Senior Animal Health Officers at The Food and Agriculture Organization of the United Nations, and with contributions from international leading experts, Veterinary Vaccines: Principles and Applications is a concise and authoritative reference featuring easily readable reviews of the latest research in vaccinology and vaccine immune response to pathogens of major economic impact to livestock. It covers advice and recommendations for vaccine production, quality control, and effective vaccination schemes including vaccine selection, specifications, vaccination programs, vaccine handling in the field, application, failures, and assessment of herd protection. In addition, the book presents discussions on the current status and potential future developments of vaccines and vaccination against selected transboundary animal diseases. Provides a clear and comprehensive guide on using veterinary vaccines to protect livestock from diseases Teaches the principles of vaccinology and vaccine immune response Highlights the vaccine production schemes and standards for quality control testing Offers easy-to-read reviews of the most current research on the subject Gives readers advice and recommendations on which vaccination schemes are most effective Discusses the today’s state of vaccines and vaccination against selected transboundary animal diseases as well as possible future developments in the field Veterinary Vaccines: Principles and Applications is an important resource for veterinary practitioners, animal health department officials, vaccine scientists, and veterinary students. It will also be of interest to professional associations and NGO active in livestock industry.

Download or read book Porcine Reproductive and Respiratory Syndrome Virus Infection of Immune privileged Sites written by Jinho Shin and published by . This book was released on 1999 with total page 514 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Molecular Basis of Porcine Reproductive and Respiratory Syndrome Virus mediated Innate Immune Suppression written by and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Mechanisms of Control of Porcine Reproductive and Respiratory Syndrome Virus PRRSV Infection in Pigs written by Zhengguo Xiao and published by . This book was released on 2004 with total page 386 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Mechanisms of Porcine Reproductive and Respiratory Syndrome Virus PRRSV Control of the Host Innate Immune Response written by Christopher Overend and published by . This book was released on 2011 with total page 212 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Antibody and Cellular Immune Responses of Swine Exposed to Porcine Reproductive and Respiratory Syndrome Virus Or a GP5 Subunit Vaccine written by Kang Mi Lee and published by . This book was released on 2007 with total page 112 pages. Available in PDF, EPUB and Kindle. Book excerpt: Keywords: Respiratory, Swine, Reproductive, PRRS, PRRSV, Porcine, Virus.

Download or read book Immune Response of Swine to Porcine Reproductive and Respiratory Syndrome Virus Laboratory and Field Studies written by and published by . This book was released on 2008 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Interactions of Porcine Reproductive and Respiratory Syndrome Virus with Innate Immune Responses written by Sang-Myeong Lee and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: North American field isolates of PRRSV differed in their type I IFN response with respect to induction, sensitivity and suppression. Furthermore, one PRRSV isolate strongly enhanced polyI:C - induced IFN-[alpha] production in PAM cultures and this priming effect was suppressed by other PRRSV isolates. PRRSV activates NF-[kappa]B which is a critical regulator of innate and adaptive immune function. NF-[kappa]B activation was dependent on virus replication and I[kappa]B[alpha] degradation. ROS production was involved in NF-[kappa]B activation by PRRSV. NF-[kappa]B dependent expression of MMP-2 and MMP-9 suggested a possible role of the NF-[kappa]B pathway in PRRSV pathogenesis and the immune response. PRRSV infection induced both intrinsic and extrinsic apoptosis pathways and linked these two pathways via Bid cleavage by caspase-8. While apoptosis was significantly suppressed by caspase inhibitors, the same inhibitors did not affect PRRSV replication. This study also provided evidence of a possible involvement of NF-[kappa]B and ROS in apoptosis induced by PRRSV.

Download or read book Characterizing the Porcine Adaptive Immune Response to Homologous Heterologous Porcine Reproductive and Respiratory Syndrome Virus Type 2 PRRSV 2 Strains written by Andrew Robert Kick and published by . This book was released on 2020 with total page 177 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Characterization of Naturally Occurring Severe Combined Immunodeficiency SCID in a Line of Pigs and Their Response to Porcine Reproductive and Respiratory Syndrome Virus PRRSV Infection written by Ada Giselle Cino-Ozuna and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Severe combined immunodeficiency (SCID) is a rare group of inherited disorders characterized by defects in both humoral and cellular immune functions. Naturally occurring SCID has been first described in humans in the 1960s and subsequently identified in horses, mice, and dogs, but never before in pigs. Affected animals are characterized by having loss of functional B and T lymphocytes, and in some cases natural killer (NK) cells, but normal numbers of monocytes, granulocytes, and megakaryocytes. As a result, affected animals fail to produce antibodies and succumb to common disease pathogens after circulating maternal antibodies decay. SCID models are extremely valuable for the understanding of molecular mechanisms of immunological processes during viral and bacterial diseases, cancer, and autoimmunity. SCID mice are widely used as the current model; however, the relevance of the murine SCID model to human and veterinary immune research is limited and there is an increasing need for a more representative model of SCID is imperative. We describe the gross, microscopic, and immunophenotypic characteristics of a line of Yorkshire pigs having naturally occurring SCID. Affected pigs lack T and B lymphocytes, but display circulating NK cells, fail to produce antibodies to viral infection, and lack cell-mediated response to tumor xenotransplants. We also describe response of SCID pigs to porcine reproductive and respiratory syndrome virus (PRRSV). PRRSV is the most devastating virus in swine industry, causing losses of billions of dollars annually. Understanding the immunopathogenesis of the disease is imperative in order to develop strategies to combat this devastating virus. PRRSV infected-SCID pigs failed to develop lesions of PRRSV infection, demonstrating the significant role of the adaptive immunity to PRRSV infection. Finally, we describe the preliminary results of the adoptive transfer of purified CD3 T lymphocytes to SCID pigs from SLA-II matched wild-type littermates, with the objective of establishing a porcine model for the study of T cell immunopathogenesis with viral diseases.