Previous Article |
Table of Contents
| Next Article
BIOLOGICAL SCIENCES / MEDICAL SCIENCES
Selective gene silencing in activated leukocytes by targeting siRNAs to the integrin lymphocyte function-associated antigen-1



,¶
,¶
*CBR Institute for Biomedical Research, and Departments of
Anesthesia and
Pediatrics, Harvard Medical School, 200 Longwood Avenue, Boston, MA 02115; and
Department of Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, 330 Brookline Avenue, Boston, MA 02215
Edited by Owen N. Witte, University of California, Los Angeles, CA, and approved January 5, 2007 (received for review September 26, 2006)
Silencing gene expression by RNAi is a powerful method for exploring gene function and validating drug targets and potentially for therapy. Lymphocytes and other primary blood cells are resistant to lipid-based transfection in vitro and are difficult to target in vivo. We show here that antibody-protamine fusion proteins targeting the human integrin lymphocyte function-associated antigen-1 (LFA-1) efficiently deliver siRNAs and specifically induce silencing in primary lymphocytes, monocytes, and dendritic cells. Moreover, a fusion protein constructed from an antibody that preferentially recognizes activation-dependent conformational changes in LFA-1 selectively targets activated leukocytes and can be used to suppress gene expression and cell proliferation only in activated lymphocytes. The siRNA-fusion protein complexes do not cause lymphocyte activation or induce IFN responses. K562 cells expressing latent WT or constitutively activated LFA-1 engrafted in the lungs of SCID mice are selectively targeted by intravenously injected fusion protein–siRNA complexes, demonstrating the potential in vivo applicability of LFA-1-directed siRNA delivery.
affinity up-regulation | antiinflammation | cell adhesion molecule | drug delivery | AL-57 and TS1/22
This article is a PNAS direct submission.
This article contains supporting information online at www.pnas.org/cgi/content/full/0608491104/DC1.
¶To whom correspondence may be addressed. E-mail: shimaoka{at}cbrinstitute.org and lieberman{at}cbr.med.harvard.edu
© 2007 by The National Academy of Sciences of the USA
![]()
CiteULike
Complore
Connotea
Del.icio.us
Digg What's this?
This article has been cited by other articles in HighWire Press-hosted journals:
![]() |
X. Cullere, M. Lauterbach, N. Tsuboi, and T. N. Mayadas Neutrophil-selective CD18 silencing using RNA interference in vivo Blood, April 1, 2008; 111(7): 3591 - 3598. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. Peer, E. J. Park, Y. Morishita, C. V. Carman, and M. Shimaoka Systemic Leukocyte-Directed siRNA Delivery Revealing Cyclin D1 as an Anti-Inflammatory Target Science, February 1, 2008; 319(5863): 627 - 630. [Abstract] [Full Text] [PDF] |
||||
![]() |
B. Liu Exploring cell type-specific internalizing antibodies for targeted delivery of siRNA Brief Funct Genomic Proteomic, July 31, 2007; (2007) elm015v1. [Abstract] [Full Text] [PDF] |
||||