Ultrasound-Mediated Remotely Controlled Nanovaccine Delivery for Tumor Vaccination and Individualized Cancer Immunotherapy.

Vaccines are one of utmost important weapons in modern medicine to fight a wide range of diseases. To achieve optimal vaccination effects, repeated injections of vaccines are often required, which would largely decrease patient comfort. Herein, an ultrasound-responsive self-healing hydrogel system loaded with nanovaccines is designed for remotely controlled tumor vaccine release and individualized cancer immunotherapy. The gel could be transformed into sol status in response to ultrasound treatment, allowing a burst release of nanovaccines, and self-healed to gel afterward. For mice with a single subcutaneous injection of nanovaccine-loaded gel and multiple ultrasound treatments, repeatedly released nanovaccines could elicit antitumor immune responses, which in combination with immune checkpoint blockade could effectively inhibit established tumors, and prevent postoperative tumor metastases and recurrence based on our personalized nanovaccine system. This work presents an easy-to-operate strategy to realize controllable and durable delivery of vaccines against cancer and potentially other types of diseases.