IL-2 can enhance the cyclosporin A-mediated inhibition of Theileria parva-infected T cell proliferation.
The effect of cyclosporin A on the continuous proliferation of Theileria parva-infected T cells was tested and compared with its effect on the Con A-induced proliferation of bovine lymph node cells. The effect of rIL-2 on cyclosporin A-treated cells was also tested. Whereas the Con A-induced proliferation of bovine lymph node cells was completely inhibited by cyclosporin A, the continuous growth of T. parva-infected cells was only partly inhibited. In both cases the inhibition was accompanied by a reduction in the level of IL-2R/Tac mRNA and surface IL-2R expression. The cyclosporin A-mediated inhibition of Con-A stimulated lymphoblasts was, over a period of 5 days, largely abrogated by human rIL-2. In the short term, rIL-2 could also alleviate the growth inhibition of T. parva-infected cells caused by treatment with cyclosporin A. In the long term, however, rIL-2 enhanced the cyclosporin A-mediated inhibition of T. parva-infected cells, gradually leading to their complete growth arrest. This enhanced inhibition was accompanied by a further reduction in surface IL-2R expression, but not by a further decrease in the levels of steady state IL-2R/Tac mRNA. The fact that IL-2 can enhance the inhibition caused by cyclosporin A could be of relevance for the immunosuppressive activity of cyclosporin A.
Eichhorn
M
M
Kernforschungszentrum, Karlsruhe, Institut für Genetik und Toxikologie, FRG.
Magnuson
N S
NS
Reeves
R
R
Williams
R O
RO
Dobbelaere
D A
DA
D000818:Animals; D016782:Apicomplexa; D015152:Blotting, Northern; D002417:Cattle; D002460:Cell Line; D003208:Concanavalin A / Q000494:pharmacology; D003524:Cyclosporins / Q000494:pharmacology*; D005786:Gene Expression Regulation / Q000187:drug effects; D066298:In Vitro Techniques; D007376:Interleukin-2 / Q000494:pharmacology*; D008213:Lymphocyte Activation / Q000187:drug effects*; D015375:Receptors, Interleukin-2 / Q000235:genetics / Q000378:metabolism; D011994:Recombinant Proteins; D013601:T-Lymphocytes / Q000469:parasitology*; D013801:Theileriasis / Q000276:immunology*
D003524:Cyclosporins; D007376:Interleukin-2; D015375:Receptors, Interleukin-2; D011994:Recombinant Proteins; D003208:Concanavalin A