AAV-iRFP labelling of human mesenchymal stem cells for near-infrared fluorescence imaging

Near-IR fluorescence (NIRF) imaging is a new technology using IR fluorescent protein (iRFP) gene labelling and is potentially useful for in vivo applications. In the present study, we expressed iRFP and the TNF-related apoptosis inducing ligand gene in mesenchymal stem cells (MSCs) using adeno-associated virus (AAV) and showed that iRFP-labelled MSCs can be detected by fluorescence microscopy. We injected mice with MSCs labelled with AAV-iRFP, which we were then able to detect by whole-animal NIRF imaging. Our technique provides a visualizable, convenient and sensitive platform for research on tracking the fate of transplanted MSC cells in vivo . * AAV, : adeno-associated virus; ITR, : inverted terminal repeat; VP, : virus protein; AAVS1, : adeno-associtated virus site 1; CMV, : cytomegalovirus; DMEM, : Dulbecco’s modified Eagle’s medium; F12, : Ham’s F-12 nutrient mixture; HEK-293, : human kidney cell line(-293); pAAV, : adeno-associated virus plasmid vector; MCS, : multiple clone site; hGHpA, : polyadensinic acid; N/P, : nitrogen:phosphorus ratio; EGFP, : enhanced GFP; FP, : fluorescent protein; IRES, : internal ribosome entry site; iRFP, : IR fluorescent protein; MSC, : mesenchymal stem cell; NIRF, : Near-IR fluorescence; QF-PCR, : quantitative fluorescence PCR; rAAV, : recombinant adeno-associated virus; IVC, : individually ventilated cages; TNF, : tumor necrosis factor; TRAIL, : TNF-related apoptosis inducing ligand