Figure 3
From: Activated CD4+T cells enhance radiation effect through the cooperation of interferon-γ and TNF-α
Confirmation of the radiosensitizing effect of aCD4 on the radioresistant glioma cell line LN229. (A) γ-irradiation dose response curve. LN229 cells were treated with various doses of γ-irradiation, plated at 5 × 103/well in 200 μl CM in 96-well plate and cell viability was determined. (B, C, D) Suboptimal radiation dose of 6 Gy was chosen for subsequent experiments with aCD4 pre-sentization. On day -2, LN229 cells were pre-sensitized with 1 × 104 aCD4 [aCD4 (1)] or 2 × 104 aCD4 [aCD4 (2)]. The cells were co-cultured directly with aCD4 (B), or via transwell system (C), or treated with conditioned medium (aCD4S) (D), followed (or not) on day 1 by 6 Gy γ-irradiation. Cell growth inhibition was determined on day 5 by WST-1 assay. All experiments were performed in triplicate and repeated at least 2 times. Data represent mean values of each triplicate ± S.D. Groups labeled ** (P < 0.01) were compared to irradiation alone or aCD4 alone.