Immunoproteomic analysis of the protective response obtained with subunit and commercial vaccines against Glässer's disease in pigs

An immunoproteomic analysis of the protective response of subunit and commercial vaccines in colostrum-deprived pigs against Glasser's disease was carried out. A mixture of proteins with affinity to porcine transferrin (PAPT) from Haemophilus parasuis Nagasaki strain (serovar 5) was inoculated intramuscularly (PAPT(M)) and intratracheally (PAPT(Cp)), along with a commercial bacterin. PAPT were separated using 2 dimensional electrophoresis (2DE) gels and with them, 2DE Western blots were carried out. A total of 17 spots were identified as positive with sera of pigs from any of the three vaccinated groups, the highest number of immunoreactive proteins being detected in those having received PAPT(Cp). Among them, six proteins (FKBP-type peptidyl-prolyl cis-trans isomerase, neuraminidase exo-α-sialidase, xanthine-guanine phosphoribosyl transferase, CMP-N-acetylneuraminic acid synthetase, phenylalanyl-tRNA synthetase and glyceraldehyde 3-phosphate dehydrogenase) were found to be novel immunogens in H. parasuis. These proteins showed a high potential as candidates in future subunit vaccines against Glasser's disease. The three experimental groups developed specific systemic total IgG (IgGt), IgG1, IgG2 and IgM antibodies after immunizations. In addition, those receiving PAPT(Cp) yielded a serum IgA response.