NIR fluorescence imaging of IL-2 grown T-cell trafficking.

<p>Homing of 4T1 sensitized DiR labeled viable cells to 4T1 tumor site was seen as early as 2 hours post T-cell administration (A). Fluorescent signal was not detected at the tumor site in animals injected with the cell lysates of DiR labeled IL-2 grown T-cells (B). Quantitation of Tumor/Background ratios show, T-cells localized at the tumor site from 2 hours posts T-cell administration, peaked on day 3 and persisted up to 14 days in the animal (C). While in case of IL-2 lysate, there was no localization of 4T1 specific T cells at the tumor site.