Skip to Content
Merck
  • Suppression of proteolipid protein rescues Pelizaeus-Merzbacher disease.

Suppression of proteolipid protein rescues Pelizaeus-Merzbacher disease.

Nature (2020-07-02)
Matthew S Elitt, Lilianne Barbar, H Elizabeth Shick, Berit E Powers, Yuka Maeno-Hikichi, Mayur Madhavan, Kevin C Allan, Baraa S Nawash, Artur S Gevorgyan, Stevephen Hung, Zachary S Nevin, Hannah E Olsen, Midori Hitomi, Daniela M Schlatzer, Hien T Zhao, Adam Swayze, David F LePage, Weihong Jiang, Ronald A Conlon, Frank Rigo, Paul J Tesar
ABSTRACT

Mutations in PLP1, the gene that encodes proteolipid protein (PLP), result in failure of myelination and neurological dysfunction in the X-chromosome-linked leukodystrophy Pelizaeus-Merzbacher disease (PMD)1,2. Most PLP1 mutations, including point mutations and supernumerary copy variants, lead to severe and fatal disease. Patients who lack PLP1 expression, and Plp1-null mice, can display comparatively mild phenotypes, suggesting that PLP1 suppression might provide a general therapeutic strategy for PMD1,3-5. Here we show, using CRISPR-Cas9 to suppress Plp1 expression in the jimpy (Plp1jp) point-mutation mouse model of severe PMD, increased myelination and restored nerve conduction velocity, motor function and lifespan of the mice to wild-type levels. To evaluate the translational potential of this strategy, we identified antisense oligonucleotides that stably decrease the levels of Plp1 mRNA and PLP protein throughout the neuraxis in vivo. Administration of a single dose of Plp1-targeting antisense oligonucleotides in postnatal jimpy mice fully restored oligodendrocyte numbers, increased myelination, improved motor performance, normalized respiratory function and extended lifespan up to an eight-month end point. These results suggest that PLP1 suppression could be developed as a treatment for PMD in humans. More broadly, we demonstrate that oligonucleotide-based therapeutic agents can be delivered to oligodendrocytes in vivo to modulate neurological function and lifespan, establishing a new pharmaceutical modality for myelin disorders.

MATERIALS
Product Number
Brand
Product Description

Sigma-Aldrich
D-(+)-Glucose, ACS reagent
Sigma-Aldrich
Phosphatase Inhibitor Cocktail 2, aqueous solution (dark coloration may develop upon storage, which does not affect the activity)
Sigma-Aldrich
4′,6-Diamidino-2-phenylindole dihydrochloride, powder, BioReagent, suitable for cell culture, ≥98% (HPLC and TLC), suitable for fluorescence
Sigma-Aldrich
2-Mercaptoethanol, for molecular biology, suitable for electrophoresis, suitable for cell culture, BioReagent, 99% (GC/titration)
Sigma-Aldrich
Hexadimethrine bromide, ≥95%
Sigma-Aldrich
HEPES, ≥99.5% (titration)
Sigma-Aldrich
D.E.R. 332, used as embedding medium
Sigma-Aldrich
Phosphatase Inhibitor Cocktail 3, DMSO solution
Sigma-Aldrich
BGP-15, ≥98% (HPLC)
Sigma-Aldrich
Anti-β-Actin−Peroxidase antibody, Mouse monoclonal, clone AC-15, purified from hybridoma cell culture
Sigma-Aldrich
RIPA Buffer
Sigma-Aldrich
Sucrose, ≥99.5% (GC), BioXtra
Sigma-Aldrich
Triton X-100, laboratory grade
Sigma-Aldrich
Poly-L-ornithine hydrobromide, mol wt 30,000-70,000
Sigma-Aldrich
Laminin from Engelbreth-Holm-Swarm murine sarcoma basement membrane, 1-2 mg/mL in Tris-buffered saline, 0.2 μm filtered, BioReagent, suitable for cell culture
Sigma-Aldrich
Triton X-100, for molecular biology
Sigma-Aldrich
KIMBLE Dounce tissue grinder set, 2 mL complete
Sigma-Aldrich
Magnesium sulfate, BioReagent, suitable for cell culture, suitable for insect cell culture