There are numerous serotypes of Salmonella choleraesuis and Salmonella typhimurium based on variations in the chemical structure of the Lipopolysaccharide (endotoxin) in it’s cell wall. Conventional vaccines usually incorporate only 1 or 2 serotypes of Salmonella. Ever changing genetic shifts and drifts in the Salmonella pathogens often make these conventional serotype vaccines ineffective. Since the core antigen of the Re-17 mutant in ENDOVAC-Porci® is common in all serotypes of Salmonella, it is unaffected by these genetic changes in the Salmonella pathogens cell wall, thus allowing a single vaccine to afford protection against the various serotypes of Salmonella choleraesius and Salmonella typhimurium.
In addition, since bacterial endotoxins cause the clinical signs associated with many gram-negative diseases, anti-endotoxin activity is extremely important. It has been known for years that anti-core-antigen antibodies have been shown to prevent the effects of endotoxin-mediated diseases caused by a variety of gram-negative organisms. ENDOVAC-Porci® uses the mutagenically derived Re type mutant of Salmonella typhimurium that produces anti-core antibodes which react with the “Re core antigen” common in the cell wall of aerobic gram negative bacteria.
(Refs. listed under immune plus link 28,29,30,31,32,33, and 34)