Glycans are not necessary to maintain the pathobiological features of bovine spongiform encephalopathy

PLoS Pathog. 2022 Oct 7;18(10):e1010900. doi: 10.1371/journal.ppat.1010900. eCollection 2022 Oct.

Abstract

The role of the glycosylation status of PrPC in the conversion to its pathological counterpart and on cross-species transmission of prion strains has been widely discussed. Here, we assessed the effect on strain characteristics of bovine spongiform encephalopathy (BSE) isolates with different transmission histories upon propagation on a model expressing a non-glycosylated human PrPC. Bovine, ovine and porcine-passaged BSE, and variant Creutzfeldt-Jakob disease (vCJD) isolates were used as seeds/inocula in both in vitro and in vivo propagation assays using the non-glycosylated human PrPC-expressing mouse model (TgNN6h). After protein misfolding cyclic amplification (PMCA), all isolates maintained the biochemical characteristics of BSE. On bioassay, all PMCA-propagated BSE prions were readily transmitted to TgNN6h mice, in agreement with our previous in vitro results. TgNN6h mice reproduced the characteristic neuropathological and biochemical hallmarks of BSE, suggesting that the absence of glycans did not alter the pathobiological features of BSE prions. Moreover, back-passage of TgNN6h-adapted BSE prions to BoTg110 mice recovered the full BSE phenotype, confirming that the glycosylation of human PrPC is not essential for the preservation of the human transmission barrier for BSE prions or for the maintenance of BSE strain properties.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Brain / pathology
  • Cattle
  • Creutzfeldt-Jakob Syndrome* / pathology
  • Encephalopathy, Bovine Spongiform* / pathology
  • Humans
  • Mice
  • Mice, Transgenic
  • Polysaccharides / metabolism
  • Prions* / metabolism
  • Sheep
  • Sheep, Domestic / metabolism
  • Swine

Substances

  • Prions
  • Polysaccharides

Grants and funding

This work was supported financially by the following Spanish and European Interreg grants: RB, AGL2015-65560-R, MINECO Ministerio de Economía y Competitividad (Spanish Government) https://sede.mineco.gob.es/; RB, RTI2018-098711-B-I00, Ministerio de Ciencia, Innovación y Universidades (Spanish Government) https://www.ciencia.gob.es/; JC, RTI2018-098515-B-I00, Ministerio de Ciencia, Innovación y Universidades (Spanish Government) https://www.ciencia.gob.es/; JC, PID2021-122201OB-C21, Ministerio de Ciencia, Innovación y Universidades (Spanish Government) https://www.ciencia.gob.es/ partially supported by European Region Development Fund (ERDF) https://ec.europa.eu/regional_policy/en/funding/erdf/; RB & JJB, POCTEFA EFA148/16, European Region Development Fund (ERDF) https://ec.europa.eu/regional_policy/en/funding/erdf/. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.