14 Medical Applications of Magnetic Nanoparticles
343
Endorem
® , ferumoxides) and Resovist
® (ferucarbotran) are two common examples,
although they have been withdrawn from the market due to few number of users, and
only Resovist
® is still available in some countries [58, 63]. More recently, other SPIO
CAs have been developed to be injected intravenously, as for example the Sienna
plus
® compound [85] that is exploited to localize sentinel lymph nodes.
SPIOs major quality in MRI is their higher capability to increase the image contrast
compared to Gd-complexes. This quality comes from the high saturation magnetization of SPIOs and USPIOs and it is due to the presence of a higher number of
magnetic ions, which are responsible for such magnetization [86, 87].
In addition to their capability as MRI CAs, SPIOs and USPIOs can be used also
for other applications, for example to treat iron deficiencies in patient with specific
diseases as the iron deficiency anemia caused by chronic kidney disease [88, 89]. The
latter is for example the case of Ferumoxytol (Feraheme
® , AMAG Pharmaceuticals,
Cambridge, MA), a compound made of iron oxides nanoparticles with a carbohydrate
coating. Ferumoxytol has also interesting properties as MRI CA but it is not yet
approved for this purpose [62, 90].
In the latest years a great interest around SPIOs has born for application in stem
cell labeling and tracking for cell therapy. This application consists in a long-term
imaging of transplanted stem cells in vivo in order to monitor non-invasively their
survival, differentiation, migration, etc.[57]. Stem cells are interesting due to their
self-renewal and differentiation potency, i.e., their capability to perform several cell
cycle divisions and to differentiate into various mature specialized cell types (i.e.,
muscle cells, bone cells, nerve cells, blood cells, etc.). Modern therapies aim to use
human stem cells to repair defects in numerous diseases [91–96].
SPIOs were efficiently used to label hematopoietic and mesenchymal stem cells,
or human prostate and melanoma cancer cells [97–102], or inflamed endothelial
cells associated with atherosclerotic plaques [103]. With clinical 1.5 T or 3.0 T
MRI scanners, the minimum detectable quantity of stem cells was reported to vary
from 1000 to 100,000 cells, depending also on the cellular uptake. MRI performed
on SPIO-labelled stem cells represents a safe, non-invasive and repeatable imaging
technique to track mesenchymal stromal cells after transplantation, and it could
facilitate clinical application of cell therapy.
To date, these particles have been tested for several clinical applications and
particularly for interstitial MR lymphography [104–106], MRI for lymph node metastasis evaluation [107], MR angiography [108–114], inflammation process evaluation
[115], molecular imaging for apoptosis detection [116], liver imaging [117], blood
volume measurements [118] and MRI detection of amyloid plaques in Alzheimer’s
disease [119] and others [120].
Sentinel lymph node detection and dissection is the latest evolution of a common
procedure in the field of metastases control and tumor staging, especially for patients
affected by breast cancer. This technique consists in mapping the lymphatic path from
the first lymph node, the sentinel one, to the regional nodes. The sentinel lymph node
is the one with the highest probability of metastatic tumor occurrence, and whose
pathologic examination allows a faithful staging of the regional nodes [104]. The
sentinel lymph node identification usually consists in (i) injection of a short half-life
343
Endorem
® , ferumoxides) and Resovist
® (ferucarbotran) are two common examples,
although they have been withdrawn from the market due to few number of users, and
only Resovist
® is still available in some countries [58, 63]. More recently, other SPIO
CAs have been developed to be injected intravenously, as for example the Sienna
plus
® compound [85] that is exploited to localize sentinel lymph nodes.
SPIOs major quality in MRI is their higher capability to increase the image contrast
compared to Gd-complexes. This quality comes from the high saturation magnetization of SPIOs and USPIOs and it is due to the presence of a higher number of
magnetic ions, which are responsible for such magnetization [86, 87].
In addition to their capability as MRI CAs, SPIOs and USPIOs can be used also
for other applications, for example to treat iron deficiencies in patient with specific
diseases as the iron deficiency anemia caused by chronic kidney disease [88, 89]. The
latter is for example the case of Ferumoxytol (Feraheme
® , AMAG Pharmaceuticals,
Cambridge, MA), a compound made of iron oxides nanoparticles with a carbohydrate
coating. Ferumoxytol has also interesting properties as MRI CA but it is not yet
approved for this purpose [62, 90].
In the latest years a great interest around SPIOs has born for application in stem
cell labeling and tracking for cell therapy. This application consists in a long-term
imaging of transplanted stem cells in vivo in order to monitor non-invasively their
survival, differentiation, migration, etc.[57]. Stem cells are interesting due to their
self-renewal and differentiation potency, i.e., their capability to perform several cell
cycle divisions and to differentiate into various mature specialized cell types (i.e.,
muscle cells, bone cells, nerve cells, blood cells, etc.). Modern therapies aim to use
human stem cells to repair defects in numerous diseases [91–96].
SPIOs were efficiently used to label hematopoietic and mesenchymal stem cells,
or human prostate and melanoma cancer cells [97–102], or inflamed endothelial
cells associated with atherosclerotic plaques [103]. With clinical 1.5 T or 3.0 T
MRI scanners, the minimum detectable quantity of stem cells was reported to vary
from 1000 to 100,000 cells, depending also on the cellular uptake. MRI performed
on SPIO-labelled stem cells represents a safe, non-invasive and repeatable imaging
technique to track mesenchymal stromal cells after transplantation, and it could
facilitate clinical application of cell therapy.
To date, these particles have been tested for several clinical applications and
particularly for interstitial MR lymphography [104–106], MRI for lymph node metastasis evaluation [107], MR angiography [108–114], inflammation process evaluation
[115], molecular imaging for apoptosis detection [116], liver imaging [117], blood
volume measurements [118] and MRI detection of amyloid plaques in Alzheimer’s
disease [119] and others [120].
Sentinel lymph node detection and dissection is the latest evolution of a common
procedure in the field of metastases control and tumor staging, especially for patients
affected by breast cancer. This technique consists in mapping the lymphatic path from
the first lymph node, the sentinel one, to the regional nodes. The sentinel lymph node
is the one with the highest probability of metastatic tumor occurrence, and whose
pathologic examination allows a faithful staging of the regional nodes [104]. The
sentinel lymph node identification usually consists in (i) injection of a short half-life