Figure 5.

In vivo imaging of dendritic cells (DCs) labelled with fluorine-19 (¹⁹F) nanoparticles injected intradermally into quadriceps of patients with colorectal cancer. In these patients, approximately 1 × 10⁷ labelled cells were injected. (a) A representative ¹⁹F MRS spectrum of patient at 4 h post inoculation. The DCs appear as a single narrow peak. “Reference” is from an external tube containing triflouroacetic acid placed alongside the patient. (b) Axial composite ¹⁹F/¹H images of the right thigh at 4 h post inoculation in three patients, a 53-year-old female (left), a 45-year-old female (middle) and a 61-year-old male (right), where the DCs are rendered in “hot-iron” pseudocolor and the ¹H anatomy is displayed in greyscale (F, femur; RF, rectus femoris; SFA, superficial femoral artery; LN, inguinal lymph node). (c) The results of the in vivo quantification of apparent cell numbers using the ¹⁹F MRI data, measured in two patients. By approximately 24 h post inoculation, roughly half of the injected DCs were still present at the injection site. Reprinted from Bonetto et al³⁹ with permission from John Wiley and Sons.