Targeted microbubbles with ultrasound irradiation and PD-1 inhibitor to increase antitumor activity in B-cell lymphoma

AIM: Severe cardiac toxicity of doxorubicin and an immunosuppressive tumor micro-environment become main obstacles for the effective treatment of B-cell lymphoma. In this research, rituximab-conjugated and doxorubicin-loaded microbubbles (RDMs) were designed for exploring a combination approach of targeted microbubbles with ultrasound (US) irradiation and PD-1 inhibitor to overcome obstacles mentioned above. METHODS: In vivo studies were performed on SU-DHL-4 cell-grafted mice and ex vivo studies were performed on CD20+ human SU-DHL-4 cells and human T cells. RESULTS: A greater therapeutic effect and higher expression of PD-L1 protein expression were obtained with RDMs with US irradiation in vivo. A significant inhibitory effect on SU-DHL-4 B-cell lymphoma cells was observed after treated by RDMs with US irradiation and PD-1 inhibitor ex vivo. CONCLUSION: Combination of RDMs with US irradiation and PD-1 inhibitor could be a promising therapeutic strategy for B-cell lymphoma.