Positive-contrast imaging in the rabbit hind-limb of transplanted cells bearing endocytosed superparamagnetic beads.
Positive-contrast methods can augment negative-contrast methods for CMR evaluation of transplanted cell fate in vivo. This study correlated positive-contrast signal characteristics in the rabbit hind-limb with xenograft cell number (rat fibroblasts bearing endocytosed 1 microm Bang's particles) at different stages of Gd-DTPA administration and 1 mm2 in-plane resolution (2 minute scans, 1.5 Tesla). Linear regressions modeled satisfactorily the cell number dependencies of signal-to-noise (SNR) and area-of-enhancement (R > 0.83), over approximately a 50-fold fluctuation in cell number to a lowest detected limit of 25k cells during Gd-DTPA administration. Gd-DTPA administration elevated the slopes of parameter regressions by four or more standard deviations.
Foltz
Warren D
WD
Department of Cardiology, St. Michael's Hospital, Toronto, Ontario, Canada. warren.foltz@sw.ca
Cunningham
Charles H
CH
Mutsaers
Anthony J
AJ
Conolly
Steven M
SM
Stewart
Duncan J
DJ
Dick
Alexander J
AJ
D000818:Animals; D003287:Contrast Media; D005347:Fibroblasts / Q000637:transplantation*; D019786:Gadolinium DTPA; D006614:Hindlimb / Q000473:pathology*; D007089:Image Enhancement; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008280:Magnetics; D011817:Rabbits; D051381:Rats; D012044:Regression Analysis; D014183:Transplantation, Heterologous
D003287:Contrast Media; D019786:Gadolinium DTPA