摘要
It has been shown that IL-2 and IL-15 can have opposing effects on life and death of T cells.However,the roie of IL-2 and IL-15 in regulating the fate of other cell types is less clear.In the present study,we examined the impact of IL-2 and IL-15 on life and death of pre-B cells using the BAF-B03 line.We showed that BAF-B03 cells constitutively expressed the private IL-2Rα chain and IL-15Rα chain,and the shared IL-2Rβ chain and γc chain.Stimulation of BAF-B03 cells in vitro with IL-2 and IL-15 induced vigorous cell proliferation in a dose-dependent fashion.Titration of IL-2 and IL-15 in the assay showed that the mitotic effects of IL-2 and IL-15 were remarkably similar.However,the sensitivities of BAF-B03 cells to Fas mediated apoptosis after IL-2 and IL-15 stimulation were strikingly different.Cells cultured in IL-2 readily underwent apoptotic cell death upon cross-linking of the Fas receptor whereas cells cultured in IL-15 were extremely resistant to Fas triggered cell death.The anti-apoptotic effect of IL-15 in this model was associated with increased expression of Bcl-xL. FLIP expression,however,was comparable between IL-2 and IL-15 stimulated cells.We conclude that IL-2 and IL-15 have diametrically opposite effect on the fate of BAF-B03 cells,although both cytokines share similar receptor structure and exhibit similar mitotic activities.Cellular & Molecular Immunology.2004;1(2):123-128.
It has been shown that IL-2 and IL-15 can have opposing effects on life and death of T cells.However,the roie of IL-2 and IL-15 in regulating the fate of other cell types is less clear.In the present study,we examined the impact of IL-2 and IL-15 on life and death of pre-B cells using the BAF-B03 line.We showed that BAF-B03 cells constitutively expressed the private IL-2Rα chain and IL-15Rα chain,and the shared IL-2Rβ chain and γc chain.Stimulation of BAF-B03 cells in vitro with IL-2 and IL-15 induced vigorous cell proliferation in a dose-dependent fashion.Titration of IL-2 and IL-15 in the assay showed that the mitotic effects of IL-2 and IL-15 were remarkably similar.However,the sensitivities of BAF-B03 cells to Fas mediated apoptosis after IL-2 and IL-15 stimulation were strikingly different.Cells cultured in IL-2 readily underwent apoptotic cell death upon cross-linking of the Fas receptor whereas cells cultured in IL-15 were extremely resistant to Fas triggered cell death.The anti-apoptotic effect of IL-15 in this model was associated with increased expression of Bcl-xL. FLIP expression,however,was comparable between IL-2 and IL-15 stimulated cells.We conclude that IL-2 and IL-15 have diametrically opposite effect on the fate of BAF-B03 cells,although both cytokines share similar receptor structure and exhibit similar mitotic activities.Cellular & Molecular Immunology.2004;1(2):123-128.