title: Mannose-coated gadolinium liposomes for improved magnetic resonance imaging in acute pancreatitis.
abstract: BACKGROUND
  Acute pancreatitis (AP) is an acute inflammatory condition of the pancreas. The symptoms, treatment, and prognosis of mild and severe AP are different, and severe AP is a potentially life-threatening disease with a high incidence of complications and high mortality rate. Thus, it is urgent to develop an effective approach to reliably discriminate between mild and severe AP.
  
  
  METHODS
  We have developed novel gadolinium-diethylenetriaminepentaacetic (Gd-DTPA)-loaded mannosylated liposomes (named thereafter M-Gd-NL) that preferably target macrophages in AP. The targeting ability of M-Gd-NL toward macrophages in AP and its ability to discriminate between mild and severe AP were evaluated.
  
  
  RESULTS
  The liposomes were of desired particle size (~100 nm), Gd-DTPA encapsulation efficiency (~85%), and stability. M-Gd-NL and non-targeted Gd-DTPA-loaded liposomes (Gd-NL) exhibited increased relaxivity compared with Gd-DTPA. Compared with Gd-NL and Gd-DTPA, M-Gd-NL showed increased uptake in macrophages, resulting in increased T1imaging ability both in vitro (macrophage cell line) and in vivo (severe AP model). Importantly, M-Gd-NL had the ability to discriminate between mild and severe AP, as reflected by a significantly higher T1magnetic resonance imaging signal in severe AP than in mild AP. M-Gd-NL did not show severe organ toxicity in rats.
  
  
  CONCLUSIONS
  Our data suggest that M-Gd-NL had enhanced magnetic resonance imaging ability by targeting macrophages in AP and good ability to discriminate between mild and severe AP. We believe that M-Gd-NL could shed new light on the diagnosis of AP in the near future.
authors.affiliation: Department of Radiology.
authors.forename: Bing
authors.initials: B
authors.lastname: Tian
authors.affiliation: Department of Radiology.
authors.forename: Ri
authors.initials: R
authors.lastname: Liu
authors.affiliation: Department of Radiology.
authors.forename: Shiyue
authors.initials: S
authors.lastname: Chen
authors.affiliation: Department of Radiology.
authors.forename: Luguang
authors.initials: L
authors.lastname: Chen
authors.affiliation: Department of Radiology.
authors.forename: Fang
authors.initials: F
authors.lastname: Liu
authors.affiliation: Department of Radiology.
authors.forename: Guorong
authors.initials: G
authors.lastname: Jia
authors.affiliation: Department of Radiology.
authors.forename: Yinmei
authors.initials: Y
authors.lastname: Dong
authors.affiliation: Department of Radiology.
authors.forename: Jing
authors.initials: J
authors.lastname: Li
authors.affiliation: Center of Clinical and Translational Medicine, Shanghai Changhai Hospital, The Second Military Medical University; Sunlipo Biotech Research Center for Nanomedicine, Shanghai, People's Republic of China.
authors.forename: Huaiwen
authors.initials: H
authors.lastname: Chen
authors.affiliation: Department of Radiology.
authors.forename: Jianping
authors.initials: J
authors.lastname: Lu
mesh_terms: D000208:Acute Disease; D000818:Animals; D003287:Contrast Media; D004195:Disease Models, Animal; D005434:Flow Cytometry; D019786:Gadolinium DTPA / Q000008:administration & dosage / Q000493:pharmacokinetics*; D008081:Liposomes / Q000008:administration & dosage / Q000493:pharmacokinetics*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008358:Mannose / Q000737:chemistry*; D010195:Pancreatitis / Q000175:diagnosis* / Q000000981:diagnostic imaging; D051381:Rats; D017207:Rats, Sprague-Dawley; D014018:Tissue Distribution
chemical_list: D003287:Contrast Media; D008081:Liposomes; D019786:Gadolinium DTPA; D008358:Mannose
keywords: Gd-DTPA; acute pancreatitis; liposomes; macrophages; mannose receptors