Potent antiscrapie activities of degenerate phosphorothioate oligonucleotides.
Although transmissible spongiform encephalopathies (TSEs) are incurable, a key therapeutic approach is prevention of conversion of the normal, protease-sensitive form of prion protein (PrP-sen) to the disease-specific protease-resistant form of prion protein (PrP-res). Here degenerate phosphorothioate oligonucleotides (PS-ONs) are introduced as low-nM PrP-res conversion inhibitors with strong antiscrapie activities in vivo. Comparisons of various PS-ON analogs indicated that hydrophobicity and size were important, while base composition was only minimally influential. PS-ONs bound avidly to PrP-sen but could be displaced by sulfated glycan PrP-res inhibitors, indicating the presence of overlapping binding sites. Labeled PS-ONs also bound to PrP-sen on live cells and were internalized. This binding likely accounts for the antiscrapie activity. Prophylactic PS-ON treatments more than tripled scrapie survival periods in mice. Survival times also increased when PS-ONs were mixed with scrapie brain inoculum. With these antiscrapie activities and their much lower anticoagulant activities than that of pentosan polysulfate, degenerate PS-ONs are attractive new compounds for the treatment of TSEs.
Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, USA.
David A
DA
Kocisko
Andrew
A
Vaillant
Kil Sun
KS
Lee
Kevin M
KM
Arnold
Nadine
N
Bertholet
Richard E
RE
Race
Emily A
EA
Olsen
Jean-Marc
JM
Juteau
Byron
B
Caughey
D000818:Animals; D001482:Base Composition; D002460:Cell Line; D006224:Cricetinae; D057927:Hydrophobic and Hydrophilic Interactions; D020128:Inhibitory Concentration 50; D007274:Injections, Intraperitoneal; D007279:Injections, Subcutaneous; D051379:Mice; D008822:Mice, Transgenic; D008970:Molecular Weight; D009690:Nucleic Acid Conformation; D009841:Oligonucleotides / Q000008:administration & dosage / Q000737:chemistry / Q000494:pharmacology*; D010710:Phosphates / Q000737:chemistry*; D018620:PrPSc Proteins / Q000037:antagonists & inhibitors* / Q000235:genetics; D012608:Scrapie / Q000378:metabolism* / Q000517:prevention & control*; D013534:Survival
D009841:Oligonucleotides; D010710:Phosphates; D018620:PrPSc Proteins; C083120:phosphorodithioic acid