Perfluorohexane-loaded macrophages as a novel ultrasound contrast agent: a feasibility study.
OBJECTIVE
We investigated in vitro the potential of macrophages to act as targeted vehicle for ultrasound molecular imaging.


METHODS
Murine bone marrow-derived macrophages (BMM), incubated for 3 h with different concentrations of perfluorohexane (PFH) emulsions, were monitored by microscopy, flow cytometry, and ultrasound. Effects of PFH loading on BMM adhesion molecule (PSGL-1, VLA-4, Mac-1, LFA-1) expression were analyzed by flow cytometry. Static adhesion of PFH loaded BMM to unstimulated and TNF-alpha stimulated b.End5 endothelial cells was assessed by microscopy.


RESULTS
Incubation of BMM with PFH emulsions resulted in dose-dependent uptake and increased echogenicity (max. 17 dB). Flow cytometry analyses revealed no down-regulation related to PFH loading of BMM adhesion molecule expression. Endothelial adhesion remained functional, even after 24 h, although PFH loading dose-dependently attenuated static adhesion.


CONCLUSIONS
PFH loaded BMM may potentially serve as ultrasound contrast agent for noninvasive detection of atherogenic hotspots in arteries.
Department of Biophysics, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, P. O. Box 616, 6200 MD, Maastricht, The Netherlands.
Liselotte M
LM
Kornmann
Daniëlle M J
DM
Curfs
Evelien
E
Hermeling
Ingeborg
I
van der Made
Menno P J
MP
de Winther
Robert S
RS
Reneman
Koen D
KD
Reesink
Arnold P G
AP
Hoeks
D000818:Animals; D001853:Bone Marrow / Q000378:metabolism; D002448:Cell Adhesion; D015815:Cell Adhesion Molecules / Q000378:metabolism; D002478:Cells, Cultured; D003287:Contrast Media / Q000378:metabolism*; D005240:Feasibility Studies; D005466:Fluorocarbons / Q000378:metabolism*; D008264:Macrophages / Q000166:cytology / Q000000981:diagnostic imaging* / Q000378:metabolism*; D051379:Mice; D008810:Mice, Inbred C57BL; D014463:Ultrasonography
D015815:Cell Adhesion Molecules; D003287:Contrast Media; D005466:Fluorocarbons; C078626:perflexane