Magnetically-labeled sensitized splenocytes to identify glioma by MRI: a preliminary study.
This study investigated the feasibility of imaging the migration and incorporation of magnetically-labeled sensitized splenocytes in an experimental 9L glioma brain tumor model. Splenocytes collected from tumor-bearing (sensitized splenocytes) or control (nonsensitized splenocytes) host rats were analyzed to determine the population of different cells, labeled with ferumoxides-protamine sulfate (FePro) and injected intravenously to recipient rats (N=4, for each group) bearing intracranial 9L tumors. Day 3 postinjection of splenocytes multiecho T2*-weighted and three-dimensional (3D) gradient echo MRI were obtained using a 7 Tesla MR system. R2* (1/T2*) maps were created from the T2*-weighted images. Signal intensities (SIs) and R2* values in the tumors and contralateral brain were determined by hand drawn regions of interest (ROIs). Brain sections were stained for the evidence of administered cells. Both 3D and T2*-weighted MRI showed low signal intensity areas in and around the tumors in rats that received labeled sensitized splenocytes. Prussian blue (PB), CD45- and CD8-positive cells were present in areas at the corresponding sites of low signal intensities seen on MRI. Rats that received labeled nonsensitized splenocytes did not show low signal intensity areas or PB positive cells in or around the implanted tumors. In conclusion, the immunogenic reaction can be exploited to delineate recurrent glioma using MRI following systemically delivered magnetically labeled sensitized splenocytes or T-cells.
Arbab
Ali S
AS
Department of Radiology, Henry Ford Hospital, Detroit, Michigan 48202, USA, and National Institutes of Health, University of Tehran, Iran. saali@rad.hfh.edu
Rad
Ali M
AM
Iskander
A S M
AS
Jafari-Khouzani
Kourosh
K
Brown
Stephen L
SL
Churchman
Jamie L
JL
Ding
Guangliang
G
Jiang
Quan
Q
Frank
Joseph A
JA
Soltanian-Zadeh
Hamid
H
Peck
Donald J
DJ
D000818:Animals; D001921:Brain / Q000473:pathology; D001932:Brain Neoplasms / Q000175:diagnosis*; D018414:CD8-Positive T-Lymphocytes / Q000473:pathology; D045744:Cell Line, Tumor; D002470:Cell Survival; D004396:Coloring Agents; D003287:Contrast Media; D003911:Dextrans; D004195:Disease Models, Animal; D005240:Feasibility Studies; D005295:Ferrocyanides; D052203:Ferrosoferric Oxide; D005434:Flow Cytometry; D018316:Gliosarcoma / Q000175:diagnosis*; D007089:Image Enhancement / Q000379:methods; D007091:Image Processing, Computer-Assisted / Q000379:methods; D021621:Imaging, Three-Dimensional / Q000379:methods; D007501:Iron; D007962:Leukocytes / Q000473:pathology; D008279:Magnetic Resonance Imaging / Q000379:methods*; D058185:Magnetite Nanoparticles; D009000:Monocytes / Q000166:cytology; D010087:Oxides; D011479:Protamines; D051381:Rats; D011916:Rats, Inbred F344; D013154:Spleen / Q000166:cytology*
D004396:Coloring Agents; D003287:Contrast Media; D003911:Dextrans; D005295:Ferrocyanides; D058185:Magnetite Nanoparticles; D010087:Oxides; D011479:Protamines; D007501:Iron; C065507:ferumoxides; C000170:ferric ferrocyanide; D052203:Ferrosoferric Oxide