title: Replacing 99mTc with 111In improves MORF/cMORF pretargeting by reducing intestinal accumulation.
abstract: OBJECTIVE
  To reduce accumulation in the abdomen by MORF/cMORF pretargeting, 111In was compared to 99mTc as the radiolabel.
  
  
  METHODS
  After receiving either 99mTc (MAG3)-cMORF or 111In (DTPA)-cMORF, normal mice were imaged and killed for pharmacokinetics. Thereafter, tumored mice were pretargeted withMORF-antibody, 48 h later were given an injection of 99mTc- or 111In-cMORF, and finally were imaged repeatedly.
  
  
  RESULTS
  The cMORF biodistribution in both normal and pretargeted tumored mice was influenced by its radiolabel. While excretion of both 99mTc-cMORF and 111In-cMORF was rapid and mainly through the kidneys, about 2% of 99mTc accumulated in the intestines compared toessentially no intestinal accumulation for 111In at any time. Tumor accumulation was unchanged.
  
  
  CONCLUSIONS
  In applications of MORF/cMORF pretargeting intended to image organs deep within the abdomen such as the pancreas, radiolabeling with 111In may be superior to 99mTc.
authors.affiliation: Division of Nuclear Medicine, Department of Radiology, University of Massachusetts Medical School, 55 Lake Ave North, Worcester, MA 01655-0243, USA. guozheng.liu@umassmed.edu
authors.forename: Guozheng
authors.initials: G
authors.lastname: Liu
authors.forename: Dengfeng
authors.initials: D
authors.lastname: Cheng
authors.forename: Shuping
authors.initials: S
authors.lastname: Dou
authors.forename: Xiangji
authors.initials: X
authors.lastname: Chen
authors.forename: Minmin
authors.initials: M
authors.lastname: Liang
authors.forename: P Hendrik
authors.initials: PH
authors.lastname: Pretorius
authors.forename: Mary
authors.initials: M
authors.lastname: Rusckowski
authors.forename: Donald J
authors.initials: DJ
authors.lastname: Hnatowich