Our laboratory focuses on developing splice modulating AOs for many different conditions, and here we show that application of AOs is not limited to rescuing gene expression, but can also down-regulate gene expression through targeted disruption of normal exon selection and mRNA maturation.

Additional splice modulating AOs are also under investigation as therapeutics for genetic diseases caused by splice mutation defects that should be amendable to correction 5. The accelerated or full approval of nucleic acid drugs by the US Food and Drug Administration is an important achievement for the field 2, and new drugs in the clinic include two splice modulating AOs Eteplirsen 3, an exon skipping phosphorodiamidate morpholino oligomer (PMO) for the treatment of a subset of Duchenne muscular dystrophy patients and Spinraza, an AO promoting exon inclusion for the treatment of Spinal muscular atrophy 4. Indeed, depending on the AO chemistry and backbone, several mechanisms of antisense action have been identified, including splice modulation that has gained momentum over the last few years. Since the first report of antisense oligonucleotides (AO) being used to block viral replication, by Zamecnik and Stephenson 1, there was great optimism for their possible application as therapeutics. This highly specific strategy to down-regulate protein expression through interfering with normal exon selection during pre-mRNA processing should be applicable to many other gene targets that undergo splicing during expression. With the promising results in ameliorating disease progression, we are optimistic that the candidate oligomer may also be applicable to many other diseases associated with integrin alpha 4 mediated inflammation. Peptide conjugated phosphorodiamidate morpholino antisense oligomers targeting ITGA4 were also assessed for their effect in delaying disease progression in the experimental autoimmune encephalomyelitis mouse model of multiple sclerosis.

Integrin alpha 4-mediated activities were evaluated in human dermal fibroblasts and Jurkat cells, an immortalised human T lymphocyte cell line. Over one hundred antisense oligonucleotides were designed to induce skipping of individual exons of the ITGA4 transcript and thereby reducing protein expression.

Our laboratory focuses on developing therapeutic splice modulating antisense oligonucleotides to treat diseases potentially amendable to intervention during pre-mRNA processing, and here we report the use of oligomers to down-regulate integrin alpha 4 protein levels. With recent approvals of antisense oligonucleotides as therapeutics, there is an increasing interest in expanding the application of these compounds to many other diseases.

Download serum through splice