Comparison of SPIO and USPIO for in vitro labelling of human monocytes with respect to MR detection and cellular activation status
Oude Engberink R, van der Pol S, de Vries H, Dopp E, Blezer E
University Medical Center Utrecht
MR imaging of target cells requires an efficient labelling method and the intracellular presence of contrast agents must not interfere with cellular function. To this end we studied in vitro labelling of primary human monocytes with iron oxides comparing SPIO Endorem with USPIO Sinerem. After labeling, cell viability, migratory capacity and cytokine profile were tested. Incubation of monocytes with Endorem (1mg Fe/ml) was optimal with respect to MR signal and unaltered cell viabilty/activity. In contrast, incubation with the smaller sized Sinerem, did not result in significant MR signal. In vitro labelling of primary monocytes with Endorem shows great potential for in vivo tracking of monocytes.