An introduction to cancer vaccine, chimeric antigen receptor (CAR) T-cell and immune checkpoint blockade

Abstract

Cancer immunotherapy has been a hot topic of cancer therapy discussion for over decades. Several successful cancer immunotherapies have already existed for about 30 years, however it is just in the past decade that immunotherapy has achieved broad breakthrough on patient survival in multiple high-incidence cancer indications. Immunotherapy, as a promising therapy depending mainly on the mechanism that immune cells work to eliminate cancer cells, has three hot topics recently. Cancer vaccine is a therapeutic vaccine that typically involves exogenous administration of selected tumour antigens to activate dendritic cells (DCs), or even DCs themselves in order to initiate and stimulate immune response to tumour cells, regain their control over tumour growth, induce existed tumour regression and eradicate minimal residual disease. Chimeric antigen receptor (CAR) T-cell therapy uses a patient's own T cells, but genetically engineered to express a synthetic receptor that binds to a tumour antigen more precisely and efficiently, to serve as more effective army against tumours. Immune checkpoint blockade (ICB) depends on blocking certain receptors and their ligands involved in pathways that attenuate T cell activation for example, cytotoxic T lymphocyte antigen 4 (CTLA4), programmed cell death 1 (PD1) and its ligand, PDL1 to restore T cells activity and prevent acquired peripheral tolerance to tumour antigens. This review gives a brief introduction to how human immune system works and a basic overview on the principles of cancer vaccine, chimeric antigen receptor (CAR) T-cell and immune checkpoint blockade (ICB).