Susceptibility toSalmonella typhimuriumInfection and Effectiveness of Vaccination in Mice Deficient in the Tumor Necrosis Factor Alpha p55 Receptor

Mice defective in the ability to produce the tumor necrosis factor alpha p55 receptor (TNFalphap55R) were orally challenged with a number of Salmonella typhimurium HWSH derivatives that differ in virulence. In comparison to TNFalphap55R+/+ mice, TNFalphap55R-/- mice succumbed earlier to challenge with wild-type S. typhimurium HWSH and S. typhimurium HWSH purE. In contrast, TNFalphap55R-/- mice were able to control an S. typhimurium HWSH aroA challenge, although greater numbers of Salmonella organisms were present in the tissues for a longer time period than was observed with TNFalphap55R+/+ mice. Vaccination of normal and TNFalphap55R knockout animals with S. typhimurium HWSH aroA showed that TNFalphap55R-/- mice, unlike TNFalphap55R+/+ mice, were not protected against a virulent S. typhimurium HWSH challenge. Splenocytes from TNFalphap55R-/- mice exhibited a reduced ability to proliferate in the presence of S. typhimurium antigen compared to TNFalphap55R+/+ mice. Thus, TNFalphap55R is essential for controlling Salmonella growth in tissues and for recall of immunity in murine salmonellosis.