@article {Bijsterbosch619, author = {Martin K. Bijsterbosch and Muthiah Manoharan and Rick Dorland and Richard van Veghel and Erik A. L. Biessen and Theo J. C. van Berkel}, title = {bis-Cholesteryl-Conjugated Phosphorothioate Oligodeoxynucleotides Are Highly Selectively Taken Up by the Liver}, volume = {302}, number = {2}, pages = {619--626}, year = {2002}, doi = {10.1124/jpet.302.2.619}, publisher = {American Society for Pharmacology and Experimental Therapeutics}, abstract = {We previously modulated, by conjugating a single cholesterol, plasma protein binding and liver cell uptake of a phosphorothioate oligodeoxynucleotide (PS-ODN). In this study, we investigated the biological fate of a PS-ODN, denoted ISIS-9389 (3',5'-bis-cholesteryl-conjugated ISIS 3082), provided with two cholesteryl moieties. After intravenous injection of into rats, [3H]ISIS-9389 was cleared from plasma with a half-life of 23.6 {\textpm} 0.3 min. After 90 min (approximately 95\% cleared), the liver contained 83.0 {\textpm} 0.8\% of the dose. Spleen and bone (marrow), which constitute with the liver the reticuloendothelial system, contained 3.1 {\textpm} 0.3 and 4.3 {\textpm} 0.2\%, respectively. All other tissues accumulated together \<5\% of the dose. The hepatic uptake of [3H]ISIS-9389 occurred mainly by endothelial cells (51.9 {\textpm} 6.4\% of the liver uptake). Parenchymal and Kupffer cells were responsible for 24.9 {\textpm} 7.7 and 23.3 {\textpm} 2.5\%, respectively. Preinjected polyinosinic acid and polyadenylic acid reduced hepatic uptake, albeit the latter was less effective. This finding suggests implication of (multiple) scavenger receptors in liver uptake of ISIS-9389. The interaction of ISIS-9389 with plasma proteins, analyzed by size exclusion chromatography, differs from that of unconjugated PS-ODN and PS-ODN with a single cholesterol. Plasma-incubated ISIS-9389 was mainly recovered as a high molecular weight complex. In conclusion, conjugation of PS-ODNs with two cholesteryl moieties results in almost quantitative uptake by the liver. The liver targeting exceeds the already impressive gain in liver uptake achieved by conjugation of a single cholesterol, and is expected to increase the therapeutic activity against liver-associated targets and reduce side effects in nonhepatic tissues. The American Society for Pharmacology and Experimental Therapeutics}, issn = {0022-3565}, URL = {https://jpet.aspetjournals.org/content/302/2/619}, eprint = {https://jpet.aspetjournals.org/content/302/2/619.full.pdf}, journal = {Journal of Pharmacology and Experimental Therapeutics} }