Therapeutic evaluation of systemic photodynamic therapy in a rat model for acute myeloid leukemia

Abstract

Objective To evaluate the efficacy of the systemic photodynamic therapy (SPDT) for treating leukemia using a Brown Norway myeloid leukemia (BNML) rat model. Methods The BNML rat model was established by injecting green fluorescent protein(GFP)-LT12 cells into the tail vein. After GFP-LT12 injection, the early-SPDT group, mid-SPDT group and late-SPDT group were treated with SPDT at 5, 10 and 15 days, the negative control group was fed as usually, and the Ara-c positive control group was treated with Ara-c at 7 days. The GFP-LT12 cells were traced by a fluorescence imaging system. The GFP-LT12 cells in the tissues and organs were detected by flow cytometry. The levels of IFN-γ, IL-1α, IL-1β, IL-2, IL-4, IL-6, IL-10 and TNF-α in serum were detected by milliplex rat cytokine 9 kits. Results Compared with the negative control group, the survival times of the rats in the early-SPDT group, mid-SPDT group and the late-SPDT group were prolonged (all P<0.05). The ratios of GFP-LT12 cells in pulp and liver were decreased in the late-SPDT group. The levels of IL-1β, IL-10, TNF-α and IFN-γ in serum of the late-SPDT group were decreased (all P<0.05). Conclusion The SPDT is an effective method for the treatment of leukemia, and the anti-tumor immune effect may play a key role in this process. Key words: Photodynamic therapy; Leukemia; Green fluorescent protein; Cytokines; Extracorporeal circulation