title: Abrogation of complex glycosylation by swainsonine results in strain- and cell-specific inhibition of prion replication.
abstract: Neuroblastoma-derived N2a-PK1 cells, fibroblastic LD9 cells, and CNS-derived CAD5 cells can be infected efficiently and persistently by various prion strains, as measured by the standard scrapie cell assay. Swainsonine, an inhibitor of Golgi α-mannosidase II that causes abnormal N-glycosylation, strongly inhibits infection of PK1 cells by RML, 79A and 22F, less so by 139A, and not at all by 22L prions, and it does not diminish propagation of any of these strains in LD9 or CAD5 cells. Misglycosylated PrP(C) formed in the presence of swainsonine is a good substrate for conversion to PrP(Sc), and misglycosylated PrP(Sc) is fully able to trigger infection and seed the protein misfolding cyclic amplification reaction. Distinct subclones of PK1 cells mediate swainsonine inhibition to very different degrees, implicating misglycosylation of one or more host proteins in the inhibitory process. The use of swainsonine and other glycosylation inhibitors described herein enhances the ability of the cell panel assay to differentiate between prion strains. Moreover, as shown elsewhere, the susceptibility of prions to inhibition by swainsonine in PK1 cells is a mutable trait.
authors.affiliation: Department of Infectology, Scripps Florida, Jupiter, Florida 33458, USA.
authors.forename: Shawn
authors.initials: S
authors.lastname: Browning
authors.forename: Christopher A
authors.initials: CA
authors.lastname: Baker
authors.forename: Emery
authors.initials: E
authors.lastname: Smith
authors.forename: Sukhvir P
authors.initials: SP
authors.lastname: Mahal
authors.forename: Maria E
authors.initials: ME
authors.lastname: Herva
authors.forename: Cheryl A
authors.initials: CA
authors.lastname: Demczyk
authors.forename: Jiali
authors.initials: J
authors.lastname: Li
authors.forename: Charles
authors.initials: C
authors.lastname: Weissmann
mesh_terms: D000818:Animals; D002460:Cell Line; D002999:Clone Cells; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D006031:Glycosylation / Q000187:drug effects; D051379:Mice; D011328:Prions / Q000737:chemistry* / Q000378:metabolism*; D011487:Protein Conformation / Q000187:drug effects; D021381:Protein Transport / Q000187:drug effects; D057165:Proteostasis Deficiencies / Q000378:metabolism; D013045:Species Specificity; D017026:Swainsonine / Q000494:pharmacology*
chemical_list: D004791:Enzyme Inhibitors; D011328:Prions; D017026:Swainsonine