Tumor-Related Exosomes Contribute to Tumor-Promoting Microenvironment: An Immunological Perspective

Figure 2

Exosomes serve as agents for immunotherapy strategy. (a) Three ways to create bioengineered exosomes: (1) Transfect exogenous antitumor antigen into exosomes directly; (2) bind the antitumor antigen onto exosome membrane surface protein LAMP-2b; (3) fuse antitumor antigen with lipid-binding C1C2 domains of the human lactadherin protein MFGE8 noncovalently. (b) Mature DCs produce DC-derived exosomes with MHC-I, MHC-II, and costimulatory molecules (CD40, CD80, and CD86) to induce immature DCs’ maturation and active cytotoxic T cells and NK cells. DC-derived exosomes could also yield a Th1-polarized immune response to proliferate cytotoxic T cells.

(a) Bioengineered exosomes

(b) DC-derived exosomes