Real-time bioluminescence imaging of macroencapsulated fibroblasts reveals allograft protection in rhesus monkeys (Macaca mulatta).

BACKGROUND: Encapsulation of cells has the potential to eliminate the need for immunosuppression for cellular transplantation. Recently, the TheraCyte device was shown to provide long-term immunoprotection of murine islets in a mouse model of diabetes. In this report, translational studies were undertaken using skin fibroblasts from an unrelated rhesus monkey donor that were transduced with an HIV-1-derived lentiviral vector expressing firefly luciferase permitting the use of bioluminescence imaging (BLI) to monitor cell survival over time and in a noninvasive manner.
METHODS: Encapsulated cells were transplanted subcutaneously (n=2), or cells were injected without encapsulation (n=1) and outcomes compared. BLI was performed to monitor cell survival.
RESULTS: The BLI signal from the encapsulated cells remained robust postinsertion and in one animal persisted for up to 1 year. In contrast, the control animal that received unencapsulated cells exhibited a complete loss of cell signal within 14 days.
CONCLUSIONS: These data demonstrate that TheraCyte encapsulation of allogeneic cells provides robust immune protection in transplanted rhesus monkeys.