title: Detection of experimental autoimmune myocarditis in rats by 111In monoclonal antibody specific for tenascin-C.
abstract: BACKGROUND
  Although the identification of inflammatory infiltrates in endomyocardial biopsy specimens is necessary for the definite diagnosis of myocarditis, the biopsy test is invasive and is not sensitive. Therefore, a new diagnostic technique for the early and noninvasive evaluation of myocarditis has been awaited. Expression of tenascin-C (TNC), one of the oligometric extracellular glycoproteins, is induced in various pathological states, including inflammation, suggesting that TNC can be a molecular marker of myocarditis.
  
  
  RESULTS
  An 111In anti-TNC monoclonal antibody Fab' fragment was injected intravenously into rats with experimental autoimmune myocarditis (EAM), and the biodistribution of this radiotracer was measured. Rapid clearance of radioactivity from the blood was observed in both EAM and control rats (<1% at 6 hours after injection). Myocardial uptake of the tracer was much higher in EAM rats than in control rats (7.54-, 4.39-, and 3.51-fold at 6, 24, and 48 hours after injection, respectively). By autoradiography, high radioactivities were clearly observed in the regions indicative of inflammation in EAM rats. Single-photon emission CT imaging demonstrated the focal myocardial uptake of 111In anti-TNC Fab' in vivo.
  
  
  CONCLUSIONS
  Radiolabeled anti-TNC Fab' may be useful for the noninvasive diagnosis of myocarditis.
authors.affiliation: Department of Cardiovascular Science and Medicine, Graduate School of Medicine, Chiba University, Chiba-shi, Chiba, Japan.
authors.forename: Mikio
authors.initials: M
authors.lastname: Sato
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Toyozaki
authors.forename: Kenichi
authors.initials: K
authors.lastname: Odaka
authors.forename: Tomoya
authors.initials: T
authors.lastname: Uehara
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Arano
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Hasegawa
authors.forename: Katsuya
authors.initials: K
authors.lastname: Yoshida
authors.forename: Kyoko
authors.initials: K
authors.lastname: Imanaka-Yoshida
authors.forename: Toshimichi
authors.initials: T
authors.lastname: Yoshida
authors.forename: Michiaki
authors.initials: M
authors.lastname: Hiroe
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Tadokoro
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Irie
authors.forename: Shuji
authors.initials: S
authors.lastname: Tanada
authors.forename: Issei
authors.initials: I
authors.lastname: Komuro
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology / Q000493:pharmacokinetics*; D001327:Autoimmune Diseases / Q000000981:diagnostic imaging / Q000378:metabolism* / Q000473:pathology; D001345:Autoradiography; D015415:Biomarkers / Q000032:analysis; D005260:Female; D007140:Immunoglobulin Fab Fragments / Q000378:metabolism; D007205:Indium Radioisotopes; D009205:Myocarditis / Q000000981:diagnostic imaging / Q000276:immunology* / Q000378:metabolism* / Q000473:pathology; D009206:Myocardium / Q000378:metabolism; D051381:Rats; D011917:Rats, Inbred Lew; D019063:Tenascin / Q000276:immunology* / Q000378:metabolism; D015899:Tomography, Emission-Computed, Single-Photon
chemical_list: D000911:Antibodies, Monoclonal; D015415:Biomarkers; D007140:Immunoglobulin Fab Fragments; D007205:Indium Radioisotopes; D019063:Tenascin