Table of Contents
International Journal of Molecular Imaging
Volume 2012, Article ID 464810, 7 pages
http://dx.doi.org/10.1155/2012/464810
Research Article

111Indium Labelling of Recombinant Activated Coagulation Factor VII: In Vitro and Preliminary In Vivo Studies in Healthy Rats

1Institute of Biomedical Sciences, Faculty of Health Sciences, University of Copenhagen, DK-2200, Copenhagen, Denmark
2Faculty of Medical Laboratory Science, Metropolitan University College, DK-2200, Copenhagen, Denmark
3Cluster for Molecular Imaging, Faculty of Health Sciences, University of Copenhagen, DK-2200, Copenhagen, Denmark
4Department of Clinical Physiology, Nuclear Medicine & PET, Rigshospitalet, University of Copenhagen, DK-2100, Copenhagen, Denmark

Received 7 September 2011; Revised 28 October 2011; Accepted 28 October 2011

Academic Editor: Weibo Cai

Copyright © 2012 Amarnadh Nalla et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

The aim of this study is to investigate whether 111Indium-labelled recombinant FVIIa (rFVIIa) could be a potential radiopharmaceutical for localization of bleeding sources. DTPA-conjugated rFVIIa was radiolabelled with 111In chloride. In vitro binding efficiency of 111In-DTPA-rFVIIa to F1A2-Mab-sepharose was 99% in buffer, while it was 88–82% in serum. The binding efficiency of 111In-DTPA-rFVIIa to TF (1–209)-sepharose was 48% in buffer whereas 39%–36% in serum, respectively. In vivo experiment was conducted in healthy rats, and gamma camera images were taken immediately after iv. administration of 1.6–1.8 MBq 111In-DTPA-rFVIIa up to 120–130 min. Five min after administration of 111In-DTPA-rFVIIa, percentage of 111In activity was 6.0% in the cardiac region and 24.5% in the liver region. After 2 hours activity was decreased to 3.3% in heart while it had increased to 42.0% in the liver. The 111In-DTPA-rFVIIa might be a potential radiopharmaceutical for visualisation of tissues with significant TF expression such as acute bleeding lesions in the gastrointestinal tract.