Cytokine response in Balb/c mice infected with Francisella tularensis LVS and the Pohang isolate.
We investigated the immune response induced by the Francisella (F.) tularensis live vaccine strain (LVS) and the Pohang isolate. After the Balb/c mice were infected intradermally (i.d) with 2 x 10(4) cfu of F. tularensis LVS and Pohang, respectively, their blood and organs were collected at different times; 0, 3, 6, 24, 72, 96, 120 and 168 h after infection. Using these samples, RT-PCR and ELISA analysis were carried out for the comparative study of the cytokines, including TNF-alpha, INF-gamma, IL-2, IL-4, IL-10 and IL-12. In the Pohang-infected mice at 120 h, the liver showed a 53 times higher level of TNF-alpha and a 42 times higher level of IFN-gamma than the respective levels at the early time points after infection. The levels of TNF-alpha and IFN-gamma induced by LVS were 5 times lower than those induced by the Pohang isolate. Also, the organs from the Pohang-infected mice showed higher levels of TNF-alpha, IFN-gamma, IL-10 and IL-12 than the levels in the LVS-infected mice. The blood from the Pohang-infected mice at 120 h revealed about a 40 times increased level of IFN-gamma, and IL-10 was also increased by 4 times at 96 h compared to an early infection time point, while IL-4 was not induced during the whole infection period. These results suggest that F. tularensis may induce a Th1-mediated immune response to in vivo infection and the Pohang isolate has a higher capacity than the LVS to induce an acute immune response in Blab/c mice.
Kim
Eun-Ju
EJ
Divison of Zoonoses, Center for Immunology and Pathology, Korea National Institute of Health, Seoul 122-701, Korea.
Park
Sang-Hee
SH
Choi
Young-Sill
YS
Shim
Soo-Kyoung
SK
Park
Mi-Yeoun
MY
Park
Man Suck
MS
Hwang
Kyu-Jam
KJ
D000818:Animals; D001428:Bacterial Vaccines; D016207:Cytokines / Q000096:biosynthesis*; D005604:Francisella tularensis / Q000276:immunology / Q000302:isolation & purification / Q000472:pathogenicity*; D006801:Humans; D007371:Interferon-gamma / Q000235:genetics / Q000378:metabolism; D007378:Interleukins / Q000235:genetics / Q000378:metabolism; D007723:Korea; D008099:Liver / Q000382:microbiology / Q000473:pathology; D051379:Mice; D008807:Mice, Inbred BALB C; D016133:Polymerase Chain Reaction; D014406:Tularemia / Q000175:diagnosis* / Q000276:immunology*; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics / Q000378:metabolism
D001428:Bacterial Vaccines; D016207:Cytokines; D007378:Interleukins; D014409:Tumor Necrosis Factor-alpha; D007371:Interferon-gamma