Nanostructured silica SBA-15 usage as an oral vaccine adjuvant to control Mycoplasma hyopmeunoniae in pig production

• Grant number: 20/05198-7
• Support Opportunities: Scholarships in Brazil - Doctorate
• Start date: November 01, 2020
• End date: May 05, 2022
• Field of knowledge: Agronomical Sciences - Veterinary Medicine - Preventive Veterinary Medicine
• Principal Investigator: Luís Guilherme de Oliveira
• Grantee: Gabriel Yuri Storino
• Host Institution: Faculdade de Ciências Agrárias e Veterinárias (FCAV). Universidade Estadual Paulista (UNESP). Campus de Jaboticabal. Jaboticabal , SP, Brazil

Abstract

Mycoplasma hyopneumoniae is the primary agent of Swine Enzootic Pneumonia, which is a chronic respiratory disease with high prevalence in commercial production. The disease has a direct impact on productivity, in addition to increase the costs associated with treatment. Despite the existence of commercial vaccines against the pathogen, the control of this bacterium is difficult, since the vaccine does not prevent colonization and shedding of the agent. Thus, the present study aims to evaluate the use of a vaccine administrated orally, composed of specific antigens extracted from Mycoplasma hyopneumoniae and incorporated into the ordered mesoporous silica type SBA-15, which has an adjuvant function, aiming to enhance the action of the intramuscular vaccine in a production environment known to be positive for the pathogen. The oral vaccine will be administered to piglets born to nulliparous females, to promote an increase in the immune response against the pathogen by stimulating the Mucosal-Associated Lymphoid Tissue (MALT), beginning in the intestinal mucosa. 48 piglets will be recruited and divided into 4 groups (n = 12), which will receive different immunization protocols. Group 1 (G1) will receive an oral vaccine dose and also a commercial single dose vaccine, on the 24th day of life; Group 2 (G2) will receive the oral vaccine on the third day of life and the commercial vaccine on the 24th day; Group 3 (G3) will receive only the commercial vaccine, simulating the natural condition of the farm on the 24th day; Group 4 (G4) will receive only the oral vaccine carrier, not associated with the antigen, and also a commercial vaccine dose, both on the 24th day. On the first day, individuals will be weighed and from the 3rd day onwards, they will be submitted to blood sampling for the monitoring of serum anti-Mycoplasma hyopneumoniae antibodies, as well as nasal swabs for IgA and shedding of the agent by monitored by ELISA and qPCR, respectively. The collection of biological samples conduced weekly from de 3rd day up to the 73rd day of lifeOn the time points, the cough and sneeze indexes of each group will also be registered. At the end of the finishing phase, individuals aged 140 days will be weighed one time more to calculate daily weight gain. At slaughter, each lung will be individually evaluated for the presence of lesions and representative fragments will be collected both for histopathological evaluation, and the detection/estimation of bacterial load by qPCR. The tracheobronchial lavage will also be collected, which will be submitted to qPCR and ELISA tests. Anti-Mhyo antibody titers and bacterial load estimates obtained by ELISA and qPCR, respectively, as well as, the body weight will be subjected to the assessment of the normality and homoscedasticity assumptions by the Shapiro-Wilk and Bartlett tests, before performing parametric statistical tests (Tukey, simple and paired T-test). In case of the data that does not fit to assumptions, it will be submitted to non-parametric analysis. For the analysis of the correlation between several variables obtained, such as antibody titers, estimation of bacterial load in biological samples, the bodyweight of individuals and degree of lung injury, models will be proposed, whose residues will be subjected to tests for the assessment of assumptions and the most appropriate correlation analysis will be employed, which can be parametric (Pearson's correlation test, regression analysis) or non-parametric (Spearman and Kendall correlation tests). (AU)

Academic Publications

(References retrieved automatically from State of São Paulo Research Institutions)

STORINO, Gabriel Yuri. Use of Nanostructured Silica SBA-15 as an Oral Vaccine Adjuvant to Control Mycoplasma hyopneumoniae in Swine Production. 2023. Doctoral Thesis - Universidade Estadual Paulista (Unesp). Faculdade de Ciências Agrárias e Veterinárias. Jaboticabal Jaboticabal.