Fig. 4. Preventing H-latch formation by pomologs rescues prion-induced neurodegeneration.
a, The densely cellular NeuN+DAPI+ cerebellar granule cell layer (CGL) of tga20 COCS was preserved by treatment with POM1 mutant hcY104A (green) but destroyed by POM1 and hcD52A (red). b, CGL degeneration occurs in prion-infected tga20 COCS, but not in COCS exposed to non-infectious brain homogenate (NBH). Treatment of RML6 prion-infected tga20 COCS with hcY104A prevented neuronal loss. c, Rescue of prion-induced toxicity by hcY104A in COCS inoculated with 22L prions. d, Treatment of prion-infected wild-type COCS, expressing wild-type levels of PrPC, with hcY104A prevented CGL degeneration. a–d, Quantification of fluorescent micrographs is depicted in Extended Data Figure 6b,g–i. Scale bar: 500 µm. e, Treatment with hcY104A (180 nM; 5 days) reduced vacuolation in chronically prion-infected Gt1 cells. Each dot represents an independent experiment with cells from different passages (1,000 cells/experiment, ordinary one-way ANOVA with Dunnett’s multiple comparisons test, ****adjusted P < 0.0001). f, Treatment of prion-infected tga20 COCS with hcY104A led to a reduction in PrPSc levels. One lane corresponds to a pool of 6–9 COCS digested with PK; PrPSc was detected using holo-POM1. The dashed bar indicates gel splicing of lanes running in non-adjacent wells on the same gel. g, Treatment of tga20 COCS with hcY104A for 7 days did not reduce PrPC levels, as determined by PrPC sandwich ELISA. §870 pM of rmPrP23230 were used as a positive control (first lane). Pomologs were pre-incubated with 600 nM of rmPrP23–230 as negative controls (last lane). Ordinate: absorbance, given as optical density at λ = 450 nm.