Cytokine mRNA profiles in trypanotolerant and trypanosusceptible cattle infected with the protozoan parasite Trypanosoma congolense: protective role for interleukin-4?
African trypanosomes are important pathogens of both humans and livestock. We investigated the association of cytokine responses with disease susceptibility in Trypanosoma congolense-infected cattle. Changes in interleukin (IL)-1beta, IL-2, IL-4, IL-5, IL-6, IL-12 p40, tumor necrosis factor-alpha (TFN-alpha), CD40L, and transforming growth factor-beta (TGF-beta) gene expression were compared in peripheral blood mononuclear cells of infected trypanotolerant N'Dama (Bos taurus) and trypanosusceptible Boran (Bos indicus) cattle. Results revealed that IL-2 transcription was decreased in both breeds of cattle at 21 days after infection. IL-12 p40 mRNA expression was increased in N'Dama cattle at 21 days after infection and at a later time in Boran cattle. The highest IL-4 mRNA expression was observed at 32 days after infection in N'Dama cattle. IL-6 mRNA expression increased in Boran cattle at 11 days after infection and was elevated at 21 and 32 days after infection in both breeds. Transcripts for IL-5 were barely detectable throughout the experimental period in both Boran and N'Dama cattle. Expression of TNF-alpha, IL-1beta, and TGF-beta mRNA did not change notably during the course of infection. In summary, differences in the expression of IL-4 and IL-6 mRNA were identified between the two breeds of cattle during infection with T. congolense, suggesting a possible protective role for IL-4 and a disease-promoting role for IL-6 in bovine trypanosomosis.
International Livestock Research Institute, Nairobi, Kenya. b.mertens@cgiar.org
B
B
Mertens
K
K
Taylor
C
C
Muriuki
M
M
Rocchi
D000818:Animals; D002417:Cattle; D002418:Cattle Diseases / Q000503:physiopathology*; D016207:Cytokines / Q000235:genetics*; D004198:Disease Susceptibility; D015870:Gene Expression; D015847:Interleukin-4 / Q000502:physiology*; D015848:Interleukin-5 / Q000502:physiology; D015850:Interleukin-6 / Q000502:physiology; D007963:Leukocytes, Mononuclear / Q000378:metabolism; D009000:Monocytes / Q000378:metabolism; D012333:RNA, Messenger / Q000032:analysis*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016212:Transforming Growth Factor beta / Q000502:physiology; D014348:Trypanosoma congolense; D014353:Trypanosomiasis, African / Q000503:physiopathology*
D016207:Cytokines; D015848:Interleukin-5; D015850:Interleukin-6; D012333:RNA, Messenger; D016212:Transforming Growth Factor beta; D015847:Interleukin-4