NOVEL ANTISENSE THERAPEUTIC FOR RHEUMATOID ARTHRITIS

Recruitment of leukocytes to injured tissue and their migration out of the vasculature is mediated in part by expression of cell adhesion molecules, including vascular cell adhesion molecule-1 (vCAM-1), on the surface of endothelial cells. Prolonged elevation of these substances is associated with a number of pathologies involving inflammation and may contribute to tissue damage through increased trafficking of leukocytes to the diseased tissue. This research aims to develop new therapeutic tools to control undesirable inflammation through down-regulation of VCAM-1. We plan to employ a novel variant of antisense therapy that directly blocks translation through an unusually strong sense-antisense interaction, allowing the targeting of coding regions of mRNAs, where existing antisense approaches are not generally effective, apparently due to disruption of the sense-antisense complex by translocating ribosomes. The new technique permits delivery of the antisense agent by a gene therapy approach as well as direct delivery of RNA using cationic lipid carriers. We will design antisense constructs targeted to regions of VCAM-1 mRNA that appear to be accessible in the cell based on published results, and deliver them using cationic lipids to HUVEC cells, assaying for their ability to down-regulate VCAM-1. If successful, this approach, which can be extended to any antisense target, is likely to increase both the effectiveness of antisense therapy in general and the number of sequences that can be targeted. The technique can also be adapted to antigene strategies. In this case, a triplex is formed in which the added third strand is tightly bound to the target duplex DNA.