ABSTRACT
Objective:To investigate the therapeutic efficacy of the combination therapy with CD47-based nanoparticles and anti-PD-L1 monoclonal antibody (αPD-L1) for preventing tumor recurrence and metastasis in vivo.Methods:BALB/c mice were used to construct 4T1 tumor-bearing mouse models. The mouse model was treated with the combination therapy to analyze the effects on local tumor recurrence, tumor growth volume, survival time and lung metastasis in the 4T1 mammary tumor-bearing mouse model.Results:The combination therapy could effectively inhibit local tumor recurrence and prolong the survival time of tumor-bearing mice ( P<0.001). Compared with the αPD-L1 group, the combination therapy can increase the expression of cytokines tumor necrosis factor-α (TNF-α) and interferon-γ (IFN-γ) in mouse serum (all P<0.05) and effector memory T cells in mouse spleen ( P<0.001). In addition, the results on the 4T1-Luc mammary tumor-bearing mouse lung metastasis model showed that the combination therapy could effectively inhibit tumor lung metastasis. Conclusions:The results strongly suggested that combination therapy with CD47-based nanoparticles and αPD-L1 can effectively elicit the memory immune response, and prevent tumor recurrence and lung metastasis.