title: The relative difference in anti-Listeria resistance of C57BL/6 and A/J mice is not eliminated by active immunization or by transfer of Listeria-immune T cells.
abstract: In this study, we examined the effects of active and adoptive immunization on the anti-Listeria resistance of innately resistant C57BL/6 and innately susceptible A/J mice. Although active immunization with a sublethal dose of viable Listeria monocytogenes markedly enhanced the anti-Listeria resistance of both C57BL/6 and A/J mice, the 100-fold difference between the two strains in innate anti-Listeria resistance was not diminished. Following immunization with an equivalent sublethal dose (0.1 LD50) of L. monocytogenes, both C57BL/6 and A/J mice generated T cells that could transfer significant and comparable protection to syngeneic recipients that were challenged with up to a 10 LD50 dose of L. monocytogenes. When the absolute number of viable Listeria was compared, however, it was clear that T cells from immunized C57BL/6 mice were capable of transferring protection to syngeneic recipients at Listeria challenge doses that were more than 100-fold greater than could T cells from Listeria-immunized A/J mice. Both active immunization and adoptive transfer of syngeneic Listeria-immune T cells enhanced the accumulation of inflammatory neutrophils and macrophages in C57BL/6 and A/J mice. More inflammatory neutrophils were recovered from actively immunized C57BL/6 than from A/J mice, whereas more inflammatory macrophages were obtained from adoptively immunized C57BL/6 than from A/J mice. These results provide further evidence for the beneficial role of inflammation in genetically determined innate resistance and T-cell mediated resistance to listeriosis. These data also suggest that some mechanism in addition to inflammatory responsiveness may be responsible for limiting the expression of acquired anti-Listeria resistance in genetically susceptible A/J mice.
mesh_terms: D000818:Animals; D002465:Cell Movement; D004198:Disease Susceptibility; D005260:Female; D007113:Immunity, Innate; D007114:Immunization; D007116:Immunization, Passive; D007156:Immunologic Memory; D008088:Listeriosis / Q000276:immunology / Q000517:prevention & control*; D008264:Macrophages / Q000276:immunology; D051379:Mice; D008805:Mice, Inbred A; D008810:Mice, Inbred C57BL; D009504:Neutrophils / Q000276:immunology; D010586:Phagocytes / Q000502:physiology; D013601:T-Lymphocytes / Q000276:immunology*