@article{oai:repo.qst.go.jp:00046288,
 author = {Kobayashi, Norihiro and Odaka, Kenichi and Uehara, Tomoya and Yoshida, Kyoko and Ohyama, Hiroyuki and Tadokoro, Hiroyuki and Hiroe, Michiaki and Fukumura, Toshimitsu and Komuro, Issei and Arano, Yasushi and 小高 謙一 and 上原 知也 and 田所 裕之 and 福村 利光 and 荒野 泰},
 issue = {23},
 journal = {Analytical Chemistry},
 month = {Nov},
 note = {Antibodies specific to a particular target molecule can be used as analytical reagents, not only for in vitro immunoassays but also for noninvasive in vivo imaging, e.g., immunoscintigraphies. In the latter case, it is important to reduce the size of antibody molecules in order to achieve suitable in vivo "diagnostic kinetics" and generate higher-resolution images. For these purposes, single-chain Fv fragments (scFvs; Mr < 30 kDa) have greater potential than intact immunoglobulins (150 kDa) or Fab (or Fab') fragments (50 kDa). Our recent observation of enhanced tenascin-C (Tnc) expression at sites of cardiac repair after myocardial infarction prompted us to develop a radiolabeled scFv against Tnc for in vivo imaging of heart disease. We cloned the genes encoding the heavy and light chain variable domains of the mouse anti-Tnc monoclonal antibody 4F10, and combined them to create a single gene. The resulting scFv-4F10 gene was expressed in E. coli cells to produce soluble scFv proteins. scFv-4F10 has an affinity for Tnc (Ka = 3.5X107 M&#8211;1), similar to the Fab fragment of antibody 4F10 (Ka = 1.3X107 M&#8211;1) and high enough to be of practical use. A cysteine residue was then added to the C-terminus to achieve site-specific 111In labeling via a chelating group. The resulting 111In-labeled scFv was administered to a rat model of acute myocardial infarction. Biodistribution and quantitative autoradiographic studies indicated higher uptake of the radioactivity at the infarcted myocardium than the noninfarcted one. Single photon emission computed tomography (SPECT) provided in vivo cardiac images that coincided with the ex vivo observations. Our results will promote advances in diagnostic strategies for heart disease.},
 pages = {9123--9130},
 title = {Toward in Vivo Imaging of Heart Disease Using a Radiolabeled Single-Chain Fv Fragment Targeting Tenascin-C},
 volume = {83},
 year = {2011}
}