Oral immunization for increased immune response in the control of Mycoplasma hyopneumoniae infection in swine

• Grant number: 18/12742-5
• Support Opportunities: Scholarships in Brazil - Doctorate
• Start date: October 01, 2018
• End date: October 17, 2021
• Field of knowledge: Agronomical Sciences - Veterinary Medicine - Animal Clinics and Surgery
• Principal Investigator: Luís Guilherme de Oliveira
• Grantee: Marina Lopes Mechler Dreibi
• Host Institution: Faculdade de Ciências Agrárias e Veterinárias (FCAV). Universidade Estadual Paulista (UNESP). Campus de Jaboticabal. Jaboticabal , SP, Brazil

Abstract

Mycoplasma hyopneumoniae, the main etiological agent of Enzootic Swine Pneumonia, is a widespread microorganism in the world swine production. Its prevention is of great interest for the productive system, since its colonization in the lung tissue leads to intense economic losses. Commercially available vaccines attenuate the clinical manifestation of the disease and lung lesions, but lead to a poor mucosal immune response and do not prevent colonization of the bacterium. Thus, this study aims at the development of a carrier-immunostimulant specific for the disease, for oral administration, by encapsulating cell wall proteins of the agent. It is sought to increase the immune response of the respiratory mucosa by stimulating the intestinal mucosa and, consequently, reducing the number/extent of lung lesions at slaughter. Fifty piglets will be divided into five groups (n=10). Group 1 (G1) of piglets vaccinated with a single-dose of commercial vaccine at 24 days of age; Group 2 (G2) of piglets exposed to the carrier-immunostimulant at 24 days of age; Group 3 (G3) containing piglets vaccinated with a single-dose commercial vaccine at 24 days of age and exposure to the immunostimulant at 55 days of age; Group 4 (G4) with piglets exposed to immunostimulant at 24 and 55 days of age; and Group 5 (G5) will constitute the control group. All animals will be challenged at 70 days of age with 5 ml of culture medium containing 106 CCU/ml of M. hyopneumoniae administered via the nasal and tracheal routes. From day one, oral fluid samples will be collected from each pen for IgA response monitoring every three days. The animals will be fortnightly submitted to physical examination (cough index), and blood samples (to obtain serum) will be collected to monitor serum antibody levels; nasal and oral swabs for monitoring mucosal antibody levels by ELISA; and laryngeal swabs for assessment of excretion of the agent by qPCR. At slaughter at 140 days of age, the lung will be evaluated for the extent of the lesions, and tracheobronchial lavage (LTB) will be collected to measure antibodies by ELISA and detection of bacterial DNA by qPCR, in addition to lung fragments for quantification of the load bacterial by qPCR and histopathology (HE). The normality of the variables will be verified by the Shapiro-Wilkins test. In case of normality, Analysis of Variance (ANOVA), simple T test and paired T test will be applied to compare the groups at different moments. If there is no normality, nonparametric tests (Wilcoxon) will be used. In order to evaluate the presence of correlation between the lung lesions and the investigated variables (antibody titer and bacterial load), the Pearson or Spearman correlation tests and the linear regression analysis will be performed. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

MECHLER-DREIBI, MARINA L.; ALMEIDA, HENRIQUE M. S.; SONALIO, KARINA; MARTINES, MARIELA A. C.; PETRI, FERNANDO A. M.; ZAMBOTTI, BEATRIZ B.; FERREIRA, MARCELA M.; STORINO, GABRIEL Y.; MARTINS, TEREZA S.; MONTASSIER, HELIO J.; et al. Oral vaccination of piglets against Mycoplasma hyopneumoniae using silica SBA-15 as an adjuvant effectively reduced consolidation lung lesions at slaughter. SCIENTIFIC REPORTS, v. 11, n. 1, NOV 17 2021. (18/12742-5, 17/17844-8, 19/19710-4)

FERREIRA, GEOVANA C.; SANCHES, THAINARA V. C.; MECHLER-DREIBI, MARINA L.; ALMEIDA, HENRIQUE M. S.; STORINO, GABRIEL Y.; SONALIO, KARINA; PETRI, FERNANDO A. M.; MARTINS, TEREZA S.; DA SILVA, LUIS CARLOS CIDES; MONTASSIER, HELIO J.; et al. Efficacy evaluation of a novel oral silica-based vaccine in inducing mucosal immunity against Mycoplasma hyopneumoniae. Research in Veterinary Science, v. 158, p. 10-pg., 2023-03-31. (20/04707-5, 18/12742-5, 17/17844-8, 19/19710-4, 20/08028-5, 21/11914-0)

Academic Publications

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

DREIBI, Marina Lopes Mechler. Oral vaccination of piglets against Mycoplasma hyopneumoniae using silica SBA-15 as an adjuvant effectively reduced consolidation lung lesions at slaughter. 2021. Doctoral Thesis - Universidade Estadual Paulista (Unesp). Faculdade de Ciências Agrárias e Veterinárias. Jaboticabal Jaboticabal.