Immunological Characterisation of Outer Membrane Proteins (OMPs) of Salmonella enterica Serovar Gallinarum

Fowl typhoid caused by Salmonella enterica serovar Gallinarum remains to be a major problem for poultry health worldwide. The emergence of multidrug-resistant strains of Salmonella with increased virulence and survivability, leading to increased morbidity and mortality, has further complicated its management. Presently available vaccines against fowl typhoid have less-than-desired efficacy and unacceptable side effects, making it pertinent to search for new immunogens suitable for vaccine formulation. The outer membrane proteins (OMPs) of Salmonella have been considered as possible candidates for protection against typhoid. The present study was conducted to characterise the OMPs of Salmonella enterica serovar Gallinarum using immunodiffusion and western blot techniques. Presence of three precipitation lines against OMP preparation in immunodiffusion test indicated the presence of at least three immunogenic OMPs in S. Gallinarum. Further, western blot analysis revealed OMP 40 as one of the most immunopotent antigen. This study suggests that OMP 40 may be the suitable target for the development of vaccine formulation against fowl typhoid.