Submitted to: International Immunology Congress
Publication Type: Abstract Only
Publication Acceptance Date: 7/2/2001
Publication Date: N/A
Technical Abstract: Pigs are considered as an important source of Toxoplasma gondii infection in humans. Major strategies for immune prophylaxis of toxoplasmosis in swine will be based on understanding the immune response against T. gondii infections. The phenotype of PBMC and the kinetics of IFNg, IL-12 and IL-10 transcriptional changes were characterized in miniature swine following oocyst infection. All pigs were fed 1000 oocysts of the VEG strain of T. gondii. Blood samples were obtained from pigs at days 0,3,6,10,17,25,32 and 40 of infection. An increase in expression of activation markers, CD25 and SLA-DQ, was detected in the 1st week, and a significant increase in CD8+ cells in the 2nd week of infection. Competitive RT-PCR and ELISA indicated an increase in IFNg mRNA, and IFNg protein, as well as a reduction in IL-10 mRNA during the 2nd week of the infection. An increase in IL-12 transcription was not observed until the 4th week. Overall, the ability of pigs to respond to T. gondii infection by simultaneously inducing proinflammatory cytokines early, and antiinflammatory cytokines after, is likely an indication of the requirement to strike a balance between controlling parasite growth and avoiding cytokine toxicity.