MRI images transplanted islet cells with help of positively charged nanoparticles

"Our data suggests that novel, positively-charged nanoparticles can be useful MRI contrast agents to monitor islet mass after transplantation," said study co-author Hirofumi Noguchi, MD, PhD, of the Department of Gastroenterological Surgery, transplant and Surgical Oncology at the Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences. "Significant graft loss immediately after islet transplantation occurs due to immunological and non-immunological events. With MRI an attractive potential tool for monitoring islet mass in vivo, efficient uptake of MRI contrast agent is required for cell labeling."

The researchers note that recent techniques of labeling islet cells with magnetic iron oxide has allowed detection of transplanted islet cells, however commercially available magnetic nanoparticles are not efficiently transduced because the cell surface is negatively charged and the negative charge of the nanoparticles. The researchers developed positively charged nanoparticles that were efficiently transduced.

"This approach could potentially be translated into clinical practice for evaluating graft survival and for monitoring therapeutic intervention during graft rejection," concluded Dr. Noguchi.

More information: Oishi, K.; Noguchi, H.; Saito, H.; Yukawa, H.; Miyamoto, Y.; Ono, K.; Murase, K.; Sawada, M.; Hayashi, S. Novel positive-charged nanoparticles for efficient magnetic resonance imaging of islet transplantation. Cell Med. 3(1):43-49; 2012. http://www.ingentaconnect.com/content/cog/cm

Provided by Cell Transplantation Center of Excellence for Aging and Brain Repair