Fig. 3

Intracellular signaling pathways involved in T cell polarization are activated by irradiation through a bystander mechanism. a. Schematic representation of the in vitro model to investigate the direct effect of irradiation on a T cell line (Jurkat cells). b. No effect of irradiation (0 to 6Gy) was observed on the activation of p38 or ribosomal protein S6 kinase 1 (S6 k1) in Jurkat cells (p > 0.05). c. Schematic representation of the co-culture model used to investigate the indirect effect of irradiation on the activation of intracellular signaling pathways involved in T cell polarization. d. In CD4⁺ cells, pre-incubation with culture media obtained from irradiated adipocytes with a dose of 3Gy resulted in higher phosphorylation levels of both p38 and S6 k1 (*p < 0.05, **p < 0.01, ***p < 0.001). No effect of the pre-incubation in culture media from irradiated adipocytes was observed on the percentage of CD4⁺ producing interferon (IFN)-γ or interleukin (IL)-4 although a trend towards an overall effect was observed on the frequency of IFN-γ producing CD4⁺ cells (p = 0.12)