FIGURE 1.

The schematic image shows the probable process with which nexosomes (NK-derived exosomes) interact with target cells. Exosomes originate from multivesicular bodies that are produced by endoplasmic reticulum and thereafter by the Golgi apparatus. They could entrap CD markers, perforin and FAS-L, which mediate cytotoxicity by interacting with FAS on the membrane of exposed cells. The acidic pH of the tumor microenvironment may impair the antitumor immune response but favors the delivery of exosomes and promotes membrane fusion. CD16 (FcγRIII) on NK cells binds the Fc-part of antibodies coating target cells and thereby leads to an activation and lysis process. NK cell indicates natural killer cell.