Cytokines inhibit the development of trophozoite-infected cells of Theileria annulata and Theileria parva but enhance the proliferation of macroschizont-infected cell lines.
The following bovine (Bo) and human (Hu) cytokines--Bo rTNF-a, Bo rIFN-g, Hu IFN-a, Hu rIL-1, Hu rIL-2--significantly inhibited the in vitro development of trophozoite-infected cells of three stocks of Theileria annulata and of Theileria parva (Muguga). However, none of these cytokines inhibited the proliferation of established T. annulata or T. parva macroschizont-infected cell lines. Indeed, Bo rTNF-a and Hu rIL-2 consistently enhanced the proliferation of macroschizont-infected cell lines of both species and the blastogenesis of uninfected lymphocytes in trophozoite-infected cultures. These results suggest that cytokines could help in resistance to challenge infections by preventing the further development of trophozoite-infected cells but provide no evidence that any of the above cytokines directly help to resolve primary infections by inhibiting the growth of macroschizont-infected cells. These findings also suggest that both TNF-a and IL-2 could play a role in the pathogenesis of Theileria infections by promoting the proliferation of macroschizont-infected cells and the associated lymphoid hyperplasia.
Preston
P M
PM
Division of Biological Sciences, Ashworth Laboratories, University of Edinburgh, Scotland, UK.
Brown
C G
CG
Richardson
W
W
D000818:Animals; D002417:Cattle; D016207:Cytokines / Q000276:immunology*; D008213:Lymphocyte Activation / Q000276:immunology*; D011994:Recombinant Proteins / Q000276:immunology; D013601:T-Lymphocytes / Q000469:parasitology*; D016796:Theileria annulata / Q000254:growth & development / Q000276:immunology*; D016797:Theileria parva / Q000254:growth & development / Q000276:immunology*; D013801:Theileriasis / Q000276:immunology
D016207:Cytokines; D011994:Recombinant Proteins