T cell-derived exosomes in tumor immune modulation and immunotherapy

Abstract

Exosomes are nanoscale vesicles secreted by most cells and have a phospholipid bilayer structure. Exosomes contain DNA, small RNA, proteins, and other substances that can carry proteins and nucleic acids and participate in communication between cells. T cells are an indispensable part of adaptive immunity, and the functions of T cell-derived exosomes have been widely studied. In the more than three decades since the discovery of exosomes, several studies have revealed that T cell-derived exosomes play a novel role in cell-to-cell signaling, especially in the tumor immune response. In this review, we discuss the function of exosomes derived from different T cell subsets, explore applications in tumor immunotherapy, and consider the associated challenges.

Keywords: T cell; cancer; exosome; immune modulation; immunotherapy; tumor.

Figure 1

The process of exosome biogenesis and secretion. The biogenesis of exosome begins at early endosome formation through endocytosis at the plasma membrane, and then the invagination of the plasma membrane of LSEs forms ILVs that are ultimately secreted as exosomes. In the end, MVBs fuse with the plasma membrane to release exosomes. Ectosome originates from the outward budding and fission of the plasma membrane, subsequently, the nascent ectosomes are released into the extracellular space.

Figure 2

CAR-T cell-derived exosomes for tumor treatment. CAR-T cell-derived exosomes express high levels of cytotoxic molecule, making them effective vectors to provide pro-apoptotic cues to target tumor cells carrying homologous antigens.