Submitted to: Brucellasis 2000
Publication Type: Abstract Only
Publication Acceptance Date: 9/7/2000
Publication Date: 2/2/2001
Citation: Pasquali, P., Adone, R., Gasbarre, L.C., Pistoia, C., Cinchini, F. 2001. Cytokine Profile Induced in Mice Vaccinated With Brucella Abortus RB51 [abstract]. Brucellasis 2000. p. 33.
Technical Abstract: Brucella abortus RB5l is a rough attenuated strain used as an alternative vaccine to B. abortus S19. The aim of the present trial was to assess the cell-mediated immune response of mice immunized by intraperitoneal injection with alive B. abortus RB5l bacteria and sacrificed at 5, 18 and 42 days after immunization, Cytokine patterns were assessed in spleen cells sstimulated with viable bacteria. Mice showed an increase in spleen weight with a peak at 18 days after immunization which was correlated with the peak number of bacteria in the spleen. Conversely, bacteria were absent in the spleen at 42 days indicating that the mice were capable of clearing bacteria from the spleen. IL-12 secretion by spleen cells was not detected unti142 days after infection, and the level was very low. IFN-gamma and IL- 10 were produced throughout the course of infection. IFN-gamma production showed an inverse correlation with the bacterial counts in spleens of immunized mice, while IL-10 production did not show any significant difference during the course of infection. Finally. IL-4 was not detected during the course of infection. These data indicate that an intraperitoneal immunization of mice with B. abortus RB51 is capable of eliciting a strong cell mediated immune response characterized by both Th1 and Th2 cytokines. The time-course analysis of the infection showed that an increase of IL-12 and IFN- gamma was inversely correlated with the bacterial counts in the spleen, suggesting a critical role of these cytokines in the clearance of the infection.