Biomaterials for vaccine-based cancer immunotherapy

Therapeutic Cancer Vaccine and Combinations With Antiangiogenic Therapies and Immune Checkpoint Blockade

Considering the high importance of immune surveillance and immune escape in the evolution of cancer, the development of immunotherapeutic strategies has become a major field of research in recent decades. The considerable therapeutic breakthrough observed when targeting inhibitory immune checkpoint molecules has highlighted the need to find approaches enabling the induction and proper activation of an immune response against cancer. In this context, therapeutic vaccination, which can induce a specific immune response against tumor antigens, is an important approach to consider. However, this strategy has its advantages and limits. Considering its low clinical efficacy, approaches combining therapeutic cancer vaccine strategies with other immunotherapies or targeted therapies have been emphasized. This review will list different cancer vaccines, with an emphasis on their targets. We highlight the results and limits of vaccine strategies and then describe strategies that combine therapeutic vaccines and antiangiogenic therapies or immune checkpoint blockade. Antiangiogenic therapies and immune checkpoint blockade are of proven clinical efficacy for some indications, but are limited by toxicity and the development of resistance. Their combination with therapeutic vaccines could be a way to improve therapeutic outcome by specifically stimulating the immune system and considering a global approach to tumor microenvironment remodeling.

A substrate-free graphene oxide-based micromotor for rapid adsorption of antibiotics

Self-propelled micro/nanomotors play a crucial role in the fields of biomedicine, energy and the environment but are limited by low throughput and a tedious fabrication approach. Here, we propose a simple microfluidics-based scheme for fabricating substrate-free graphene oxide (GO)-based micromotors of different shapes and sizes with high throughput. The micromotors are designed to possess a 'Janus'-like porous structure, and half of each micromotor is modified with hierarchical Pt nanoflowers, which can promote the wetting of Pt with an H2O2 solution and result in a high speed of movement. To investigate the applicability of the micromotors, they were employed to rapidly remove an antibiotic, namely, tetracycline, from a solution. It was found that the rapid movement of the micromotors increased the mass transfer of tetracycline and the frequency of collisions between tetracycline molecules and the micromotors, which led to a high removal efficiency. The direction of movement of the micromotors can be conveniently controlled by an external magnetic field. Furthermore, the removal efficiency and removal time as functions of the number of micromotors, the adsorption kinetics and adsorption isotherm, and the removal amount as a function of the pH were investigated. This proved that the micromotors that were constructed exhibit high adsorption capabilities for tetracycline and implied that they hold great promise for the removal of antibiotics with similar structures or other pollutants, including organic compounds, heavy metals and oil droplets.

Bioactive Nanoparticles for Cancer Immunotherapy

Currently, immunotherapy is considered to be one of the effective treatment modalities for cancer. All the developments and discoveries in this field up to the recent Nobel Prize add to the interest for research into this vast area of study. Targeting tumor environment as well as the immune system is a suitable strategy to be applied for cancer treatment. Usage of nanoparticle systems for delivery of immunotherapeutic agents to the body being widely studied and found to be a promising area of research to be considered and investigated further. Nanoparticles for immunotherapy would be one of the effective treatment options for cancer therapy in the future due to their high specificity, efficacy, ability to diagnose, imaging, and therapeutic effect. Among the many nanoparticle systems, polylactic-co-glycolic acid (PLGA) nanoparticles, liposomes, micelles, gold nanoparticles, iron oxide, dendrimers, and artificial exosomes are widely used for immunotherapy of cancer. Moreover, the combination therapy found to be the more effective way of treating the tumor. Here, we review the current trends in nanoparticle therapy and efficiency of these nanosystems in delivering antigens, adjuvants, therapeutic drugs, and other immunotherapeutic agents. This review summarizes the currently available bioactive nanoparticle systems for cancer immunotherapy.