The role of IFN-gamma in cattle infected with Theirelia sergenti.
The spleen plays an important role in cellular immunity leading to parasite elimination, especially in hemo-protozoan parasite infection. In the present study, we quantified the serum IFN-gamma in splenectomized (SP) and non-splenectomized (NSP) cows infected with Theirelia sergenti (TS) to investigate whether the spleen plays a role in the Th1-type cytokine responses in cows following parasite infection. A transient increase in IFN-gamma was observed in the early stages of infection in the NSP cows, and the cows did not develop parasitemia. In contrast, the SP cows showed no IFN-gamma response at the early stage of infection, and the cows developed parasitemia following anemia. The NSP cows produced IgG1 and IgG2 antibodies to TS-specific, whereas the SP cows showed increases only in IgG1. Increased PBMC proliferation by cocanavalin A stimulation was observed concomitant with the IFN-gamma response. Pretreatment with IFN-gamma suppressed the propagation of TS in the SP cattle. These results suggest that the spleen plays an important role in the resistance to TS infection, leading to a Th1-type immune response. IFN-gamma might contribute to the activation of immunocytes and play an important role in the immune response to resist TS proliferation.
Hagiwara
Katsuro
K
School of Veterinary Medicine, Rakuno Gakuen University, Ebetsu, Hokkaido 069-8501, Japan. k-hagi@rakuno.ac.jp
Tokuda
Masafumi
M
Baba
Tomohisa
T
Yamanaka
Hitoki
H
Kirisawa
Rikio
R
Tsuji
Masayoshi
M
Ishihara
Chiaki
C
Iwai
Hiroshi
H
D000818:Animals; D000913:Antibodies, Protozoan / Q000097:blood; D002417:Cattle; D002418:Cattle Diseases / Q000097:blood / Q000276:immunology*; D003289:Convalescence; D007111:Immunity, Cellular; D007371:Interferon-gamma / Q000276:immunology / Q000378:metabolism / Q000502:physiology*; D008297:Male; D018512:Parasitemia / Q000276:immunology / Q000662:veterinary; D013154:Spleen / Q000276:immunology* / Q000378:metabolism; D018417:Th1 Cells / Q000378:metabolism; D016794:Theileria / Q000276:immunology* / Q000472:pathogenicity; D013801:Theileriasis / Q000097:blood / Q000276:immunology*
D000913:Antibodies, Protozoan; D007371:Interferon-gamma