title: Targeted magnetic resonance imaging with intraperitoneal and intravenous streptavidin (SA)-DTPA-Gd: a comparative study in tumor-bearing nude mice.
abstract: OBJECTIVE
  To investigate the effect of streptavidin (SA)-DTPA-Gd after intraperitoneal and intravenous administration for tumor enhancement in targeted magnetic resonance imaging (MRI).
  
  
  METHODS
  Biotinylated monoclonal antibody CL3 (600 microg) was intravenously injected into 12 BALB/c nude mice with subcutaneous inoculation of LoVo cells, followed by administration of 80 microg avidin as the chaser 24 h later and then SA-DTPA-Gd was injected intravenously or intraperitoneally after another 30 min. MRI was performed before and 20, 60 min and 3, 6, 9, 12 h after the injection of the contrast agents, and the MR signal intensity of the tumor and liver was determined.
  
  
  RESULTS
  The maximum enhancement ratio of the tumor was 70.2% in the intravenous injection group and 46.4% in the intraperitoneal group, showing significant difference between them. The maximal enhancement rate of the liver was 23.7% in the intraperitoneal group and 20.4% in the intravenous group, showing no significant difference.
  
  
  CONCLUSIONS
  MR targeted imaging with biotinylated monoclonal antibody CL3 and SA-DTPA-Gd has specific enhancement effect. Higher blood level of SA-DTPA-Gd in the intravenous group facilitates the tumor enhancement in MRI in subcutaneous tumor model.
authors.affiliation: Diagnostic Imaging Center, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China. yzhyejing@hotmail.com
authors.forename: Jing
authors.initials: J
authors.lastname: Ye
authors.forename: Yi-kai
authors.initials: YK
authors.lastname: Xu
authors.forename: Xian
authors.initials: X
authors.lastname: Liu
authors.forename: Guo-shi
authors.initials: GS
authors.lastname: Lü
mesh_terms: D000230:Adenocarcinoma / Q000175:diagnosis / Q000378:metabolism; D000818:Animals; D000911:Antibodies, Monoclonal / Q000008:administration & dosage / Q000493:pharmacokinetics; D045744:Cell Line, Tumor; D015179:Colorectal Neoplasms / Q000175:diagnosis* / Q000378:metabolism; D003287:Contrast Media / Q000008:administration & dosage; D019786:Gadolinium DTPA / Q000008:administration & dosage / Q000493:pharmacokinetics; D006801:Humans; D007274:Injections, Intraperitoneal; D007275:Injections, Intravenous; D008279:Magnetic Resonance Imaging / Q000379:methods*; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D009374:Neoplasms, Experimental / Q000175:diagnosis / Q000378:metabolism; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D019809:Streptavidin / Q000008:administration & dosage / Q000493:pharmacokinetics; D014183:Transplantation, Heterologous
chemical_list: D000911:Antibodies, Monoclonal; D003287:Contrast Media; D019809:Streptavidin; D019786:Gadolinium DTPA