Measurement of phosphorothioate oligodeoxynucleotide antisense transport across the blood-brain barrier.

Phosphorothioate oligodeoxynucleotides (PODNs) can act as antisense molecules, knocking down proteins. Many PODNs have the unusual characteristic of being transported across the blood-brain barrier by a saturable system. This means that PODNs injected intravenously can accumulate in the central nervous system in quantities sufficient to knock down proteins in brain and the blood-brain barrier. A critical step in the development of PODNs that can be administered peripherally and knockdown proteins in the central nervous system is to determine the relation to the blood-brain barrier, specifically, does the PODN cross the blood-brain barrier and, if so, how fast and to what degree.