Immunization with outer membrane protein A from Salmonella enterica serovar Enteritidis induces humoral immune response but no protection against homologous challenge in chickens

Abstract

Vaccination of poultry is one promising strategy to mitigate Salmonella infection in poultry and, in turn, humans as well. We evaluated the efficacy of outer membrane protein A (OmpA) as a novel vaccine candidate against Salmonella in poultry. Native OmpA purified from Salmonella enterica serovar Enteritidis was mixed with adjuvant and administered intramuscularly to 41-d-old chicks. The vaccinated birds showed no decrease in cecal excretion and tissue colonization compared with the unvaccinated birds after oral challenge with 10 9 cfu of the homologous strain at 28 d postimmunization. However, this vaccination induced an increased level of serum anti-OmpA IgG. Similar results were obtained in the replication experiments using a recombinant OmpA with single and double doses. For the development of more effective component vaccines for avian salmonellosis, the vaccine efficacy of outer membrane proteins other than OmpA and route of immunization other than parenteral administration should be evaluated with regard to protection and immune responses, including mucosal IgA.

Molecular Detection of InvA, OmpA and Stn Genes in Salmonella Serovars from Broilers in Egypt

“…In this work it was clear that ompA gene was detected in all isolates. These agreements with results of (Kataria et al, 2013) reported that the ompA gene is found specifically in all 68 tested Salmonella serovars by PCR and (Okamura et al, 2012) who confirmed that ompA is well conserved among the different Salmonella serovars. Conclusion Our results revealed that different salmonella serotypes was obtained from broilers as s. enteritidis (43.3%) s. infantis and s. Kentucky (16.6%), s.maloma and s.bardo (6.7%) , s.gdansk , s.typhimurium and s. blegdame (3.3%).…”

Escherichia coli outer membrane protein F (OmpF): an immunogenic protein induces cross-reactive antibodies against Escherichia coli and Shigella

“…Meenakshi et al referred to an irrelevance of the increased antibody level as an indicator of a protective effect against Salmonella (Meenakshi et al 1999). There are several possible reasons for lower protection in this study: (i) the characteristic of a prokaryotic expressed system cannot provide the glycosylation, which may affect the antigenicity; (ii) the native active configuration of rOmpF after denaturation and renaturation could be altered, formation of a partially folded or misfolded conformation, which may affect the immunogenicity (Dowling et al 2007); and (iii) the anti-rOmpF sera did not reach or recognize the OmpF protein on the outer membrane of live E. coli due to the presence of lipopolysaccharide (LPS), pili, flagella, and other porin proteins, which can mask the OmpF protein (Okamura et al 2012). It was reported that OmpF and OmpC are tightly bound to the LPS (Fourel et al 1993).…”

“…Highly immunogenic OMPs can thus be exploited as vaccine candidates against several bacterial species such as Chlamydia trachomatis , Neisseria meningitides , Aeromonas hydrophila and Edwardsiella tarda (Pal et al 1997; Wright et al 2002; Khushiramani et al 2012; Yadav et al 2014; Okamura et al 2012). Among OMPs, the outer membrane protein F (OmpF) and OmpC are the two most common porins that make 2% of the total cellular protein, and OmpF is the best-characterized porin protein in terms of structural and functional characteristics (Williams et al 2000).…”

Detection of OmpA gene by PCR for specific detection of Salmonella serovars

“…Standardized PCR yielded the and has an overlapping twin-promoter arrangement. In expected single band of 1053 bp on agarose gel addition, Okamura et al [23] based on bioinformatic electrophoresis. The size for PCR product was as per analysis also reported that OmpA is well conserved the expected size of the primers which were designed to among the various Salmonella serovars.…”