Engineered human embryonic stem cell-derived lymphocytes to study in vivo trafficking and immunotherapy.

Human embryonic stem cell (hESC)-derived natural killer (NK) cells are a promising source of antitumor lymphocytes for immunotherapeutics. They also provide a genetically tractable platform well suited for the study of antitumor immunotherapies in preclinical models. We have previously demonstrated the potency of hESC-derived NK cells in vivo. Here we use both bioluminescent and fluorescent imaging to demonstrate trafficking of hESC-derived NK cells to tumors in vivo. Our dual-imaging approach allowed us to more specifically define the kinetics of NK cell trafficking to tumor sites. NK cell persistence and trafficking were further evaluated by flow cytometry and immunohistochemistry. This integrated approach provides a unique system to apply the use of human pluripotent stem cells to study the kinetics and biodistribution of adoptively transferred lymphocytes, advances broadly applicable to the field of immunotherapy.