The efficient and selective targeting of small interfering RNA (siRNA) molecules to cells could help to harness this technology for treating disease. Peer et al. (see the Perspective by Szoka) combine nanoscale liposomal packaging of siRNAs with antibody targeting to immune cells. The targeted siRNA cargo was able to find and efficiently inactivate its target, a key cell-cycle regulating molecule called cyclin D1. Furthermore, the systemic injection of the packaged siRNA particles reversed pathology in a mouse model of inflammatory bowel disease.
D. Peer, E. J. Park, Y. Morishita, C. V. Carman, M. Shimaoka, Systemic leukocyte-directed siRNA delivery revealing cyclin D1 as an anti-inflammatory target. Science 319, 627-630 (2008). [Abstract] [Full Text]