Specific antitumour immunity of HIFU-activated cytotoxic T lymphocytes after adoptive transfusion in tumour-bearing mice

AbstractPurpose: The aim of this study was to investigate the specific anti-tumour immunity of cytotoxic T lymphocytes (CTL) activated by high-intensity focused ultrasound (HIFU) after adoptive transfer in a murine tumour model. Materials and methods: H22 tumour-bearing mice were treated by either HIFU or sham-HIFU, while naive syngeneic mice were used as controls. They were sacrificed and the spleens were harvested 14 days after HIFU. T lymphocytes were obtained from the spleens, and then adoptively transferred into 40 mice each bearing a 3-day implanted H22 tumour. On day 14 after adoptive transfer, 10 mice were sacrificed in each group for assessment of the number of tumour-infiltrating T lymphocytes and interferon-gamma (IFN-γ) secreting cells. The remaining 30 mice were continuously observed for 60 days, and tumour growth, progression and survival were recorded. Results: HIFU significantly increased peripheral blood CD3+, CD4+ levels and CD4+/CD8+ ratio (P < 0.05), CTL cytotoxicity (P < 0.01) and IFN...