Magnetic nanoparticles for imaging dendritic cells

Abstract

We report the development of superparamagnetic iron oxide (SPIOs) nanoparticles and investigate the migration of SPIO-labeled dendritic cells (DCs) in a syngeneic mouse model using magnetic resonance (MR) imaging. The size of the dextran-coated SPIO is roughly 30 nm, and the DCs are capable of independent uptake of these particles, although not at levels comparable to particle uptake in the presence of a transfecting reagent. On average, with the assistance of polylysine, the particles were efficiently delivered inside DCs within one hour of incubation. The SPIO particles occupy approximately 0.35% of cell surface and are equivalent to 34.6 pg of iron per cell. In vivo imaging demonstrated that the labeled cells migrated from the injection site in the footpad to the corresponding popliteal lymph node. The homing of labeled cells in the lymph nodes resulted in a signal drop of up to 79%. Furthermore, labeling DCs with SPIO particles did not compromise cell function, we demonstrated that SPIO-enhanced MR imaging can be used to track the migration of DCs effectively in vivo. Magn Reson Med 63:1383–1390, 2010.

Tracking and evaluation of dendritic cell migration by cellular magnetic resonance imaging

“…Quantitative analysis has shown that DC can independently take up about 10 pg Fe/cell 8 , and uptake can be as high as 35 pg Fe/cell with the use of a transfection agent 55 . Transfection agents are chemical-based delivery molecules that act to enhance the uptake of nanoparticles into the cell.…”

MR Contrast in Mouse Lymph Nodes with Subcutaneous Administration of Iron Oxide Particles: Size Dependency

“…[3][4][5] Iron oxide particles may also be used for noninvasive tracking of the migration and biodistribution of immune cells. 6 Cellular tracking typically involves labeling the cells ex vivo and subsequently implanting [7][8][9][10] or systemically 11 administering particles into the living body. These labeling methods are useful for observing the migration of immune cells toward a target, such as a tumor, and their subsequent accumulation.…”

Improved proliferation of antigen-specific cytolytic T lymphocytes using a multimodal nanovaccine

“…8,25,26 Briefly, the BM cells from mouse femurs and tibias were flushed out with RPMI 1640 medium using a 27-gauge needle and collected into a 50 mL conical tube after they are passed through a nylon mesh cell strainer of 70 µm pore size. Red blood cells were lysed from the BM cells by incubation for 3 minutes in 0.83% ammonium chloride at RT.…”

“…25 In brief, the tissue sections were treated with 3% hydrogen peroxide to quench the endogenous peroxidases, followed by ultra V block (Lab Vision, Fremont, CA, USA) for 5 minutes before the addition of primary antibody. The sections were incubated with affinity-purified hamster anti-CD11c antibody (eBioscience) at 1:200 dilution for 1 hour at RT, washed in PBS ×3, incubated with biotin-conjugated secondary antibody for 1 hour, followed by treatment with the Vectastain ABC Elite kit (Vector Laboratories, Burlingame, CA, USA) and DAB (Dako, Carpinteria, CA, USA).…”