FIG. 4.

The effect of P2X7R targeting with oATP was tested in vitro. In an ELISPOT assay in which C57BL/6 splenocytes were challenged in vitro with irradiated BALB/c splenocytes (Control), oATP treatment greatly reduced the number of cells producing IFN-γ (n = 5, *P < 0.05, ***P < 0.0001 vs. Control) (A), as well as increased the number of cells producing IL-4 (n = 5, *P < 0.05 vs. Control) (B). C: oATP also inhibited the proliferation of C57BL/6 splenocytes challenged with irradiated BALB/c splenocytes measured as incorporation of ³H-thymidine (n = 5, ***P < 0.0001 vs. Control). D: No significant differences in the percentages of apoptotic cells (AnnexinV⁺7-ADD^– cells) were evident in controls compared with oATP-cultured splenocytes (representative of three different experiments). Luminex analysis of the supernatant showed reduced IFN-γ (E), IL-2 (F), IL-6 (G), and IL-17 (H) production in C57BL/6 splenocytes challenged with irradiated BALB/c splenocytes (n = 5, *P < 0.05 vs. Control). Conversely, targeting of P2X1R using the specific inhibitor NF 449 (I) or targeting of P2X3R using the specific inhibitor NF 110 (J) was unable to modulate IFN-γ production by C57BL/6 splenocytes challenged in an ELISPOT assay with irradiated BALB/c splenocytes. (A high-quality color representation of this figure is available in the online issue.)