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Basavaraj Binjawadagi,1,2 Varun Dwivedi,1 Cordelia Manickam,1,2 Kang Ouyang,1 Jordi B Torrelles,3 Gourapura J Renukaradhya1,21Food Animal Health Research Program, Ohio Agricultural Research and Development Center, 2Department of Veterinary Preventive Medicine, The Ohio State University, Wooster, OH, USA; 3Department of Microbial Infection and Immunity, The Ohio State University, Columbus, OH, USAAbstract: Porcine reproductive and respiratory syndrome (PRRS) is an economically devastating respiratory disease of pigs. The disease is caused by the PRRS virus (PRRSV), an Arterivirus which is a highly mutating RNA virus. Widely used modified live PRRSV vaccines have failed to prevent PRRS outbreaks and reinfections; moreover, safety of the live virus vaccines is questionable. Though poorly immunogenic, inactivated PRRSV vaccine is safe. The PRRSV infects primarily the lung macrophages. Therefore, we attempted to strengthen the immunogenicity of inactivated/killed PRRSV vaccine antigens (KAg), especially in the pig respiratory system, through: 1) entrapping the KAg in biodegradable poly(lactic-co-glycolic acid) nanoparticles (NP-KAg); 2) coupling the NP-KAg with a potent mucosal adjuvant, whole cell lysate of Mycobacterium tuberculosis (M. tb WCL); and 3) delivering the vaccine formulation twice intranasally to growing pigs. We have previously shown that a single dose of NP-KAg partially cleared the challenged heterologous PRRSV. Recently, we reported that NP-KAg coupled with unentrapped M. tb WCL significantly cleared the viremia of challenged heterologous PRRSV. Since PRRSV is primarily a lung disease, our goal in this study was to investigate lung viral load and various immune correlates of protection at the lung mucosal surfaces and its parenchyma in vaccinated heterologous PRRSV-challenged pigs. Our results indicated that out of five different vaccine-adjuvant formulations, the combination of NP-KAg and unentrapped M. tb WCL significantly cleared detectable replicating infective PRRSV with a tenfold reduction in viral RNA load in the lungs, associated with substantially reduced gross and microscopic lung pathology. Immunologically, strong humoral (enhanced virus neutralization titers by high avidity antibodies) and cell-mediated immune responses (augmented population of interferon-γ secreting CD4+ and CD8+ lymphocytes and reduced secretion of immunosuppressive cytokines) in the lungs were observed. In conclusion, combination of NP-KAg and soluble M. tb WCL elicits broadly cross-protective anti-PRRSV immunity in the pig respiratory system.Keywords: PRRSV, mucosal vaccine, PLGA nanoparticles, cross-protection, M. tb WCL

Basavaraj Binjawadagi,1,2 Varun Dwivedi,1 Cordelia Manickam,1,2 Kang Ouyang,1 Yun Wu,3 Ly James Lee,3 Jordi B Torrelles,4 Gourapura J Renukaradhya1,21Food Animal Health Research Program, Ohio Agricultural Research and Development Center, 2Department of Veterinary Preventive Medicine, Ohio State University, Wooster, OH, USA; 3NanoScale Science and Engineering Center for Affordable Nanoengineering of Polymeric Biomedical Devices, 4Department of Microbial Infection and Immunity, Ohio State University, Columbus, OH, USAAbstract: Porcine reproductive and respiratory syndrome (PRRS), caused by the PRRS virus (PRRSV), is an economically devastating disease, causing daily losses of approximately $3 million to the US pork industry. Current vaccines have failed to completely prevent PRRS outbreaks. Recently, we have shown that poly(lactic-co-glycolic) acid (PLGA) nanoparticle-entrapped inactivated PRRSV vaccine (NP-KAg) induces a cross-protective immune response in pigs. To further improve its cross-protective efficacy, the NP-KAg vaccine formulation was slightly modified, and pigs were coadministered the vaccine twice intranasally with a potent adjuvant: Mycobacterium tuberculosis whole-cell lysate. In vaccinated virulent heterologous PRRSV-challenged pigs, the immune correlates in the blood were as follows: 1) enhanced PRRSV-specific antibody response with enhanced avidity of both immunoglobulin (Ig)-G and IgA isotypes, associated with augmented virus-neutralizing antibody titers; 2) comparable and increased levels of virus-specific IgG1 and IgG2 antibody subtypes and production of high levels of both T-helper (Th)-1 and Th2 cytokines, indicative of a balanced Th1–Th2 response; 3) suppressed immunosuppressive cytokine response; 4) increased frequency of interferon-γ+ lymphocyte subsets and expanded population of antigen-presenting cells; and most importantly 5) complete clearance of detectable replicating challenged heterologous PRRSV and close to threefold reduction in viral ribonucleic acid load detected in the blood. In conclusion, intranasal delivery of adjuvanted NP-KAg vaccine formulation to growing pigs elicited a broadly cross-protective immune response, showing the potential of this innovative vaccination strategy to prevent PRRS outbreaks in pigs. A similar approach to control other respiratory diseases in food animals and humans appears to be feasible.Keywords: porcine reproductive and respiratory syndrome, mucosal vaccine, nanoparticles, cross-protection, pigs

In this paper the investigation of the FSW result characteristics on AA7075-T6 of the highest grade is carried out using different process parameters. A vertical milling machine with different FSW tool geometry is used to weld AA7075. When the tool rotational speed varies from 1200 and 1800 (rpm), different welding parameters are studied, the plunge depth of tool is between 0.14 and 0.20 mm, the table transverse speed range is between 20 and 50 (mm/min) and the tool shoulder diameter was 20 mm. The welding settings are optimized using the Taguchi approach. In this experimental investigation Taguchi Technique is utilized in this study to optimize three factorial and three level designs. The results show that when the rotating speed increases, the UTS of the welded joint increases, whereas the tensile strength of the welded joint decreases resulting to frictional heat created during the FSW process. Tensile strength decreases as feed increases and increases as rotational speed increases. For a 5 mm thick plate, tensile strength is optimal with a tool shoulder diameter of 20 mm, a rotational speed of 1600 rpm, feed rate of 30 mm/min and plunge depth. The shoulder diameter of 20 mm provides the maximum ultimate tensile strength when it is compared with all other tool shoulder diameter. The Al alloy AA7075-T6 plates, however, concurrently developed an equiaxial grain structure with a substantially smaller grain size and coarsened the precipitates. [ABSTRACT FROM AUTHOR]