title: Lymph nodal prion replication and neuroinvasion in mice devoid of follicular dendritic cells.
abstract: Variant Creutzfeldt-Jakob disease and scrapie are typically initiated by extracerebral exposure to prions, and exhibit early prion accumulation in germinal centers. Follicular dendritic cells (FDCs), whose development and maintenance in germinal centers depends on tumor necrosis factor (TNF) and lymphotoxin (LT) signaling, are thought to be indispensable for extraneural prion pathogenesis. Here, we administered prions intraperitoneally to mice deficient for TNF and LT signaling components. LT alpha(-/-), LT beta(-/-), LT betaR(-/-), and LT alpha(-/-) x TNFalpha(-/-) mice resisted infection and contained no infectivity in spleens and lymph nodes (when present). However, TNFR1(-/-), TNFR2(-/-), and some TNFalpha(-/-) mice developed scrapie similarly to wild-type mice. High prion titers were detected in lymph nodes, but not spleens, of TNFR1(-/-) and TNF alpha(-/-) mice despite absence of FDCs and germinal centers. Transfer of TNFR1(-/-) fetal liver cells into lethally irradiated Prnp(0/0) mice restored infectivity mainly in lymph nodes. Prion protein (PrP) colocalized with a minority of macrophages in tumor necrosis factor receptor (TNFR) 1(-/-) lymph nodes. Therefore, prion pathogenesis can be restricted to lymphoreticular subcompartments, and mature follicular dendritic cells are dispensable for this process. Macrophage subsets are plausible candidates for lymphoreticular prion pathogenesis and neuroinvasion in the absence of FDCs, and may represent a novel target for postexposure prophylaxis.
authors.affiliation: Institute of Neuropathology, University Hospital of Zurich, Schmelzbergstrasse 12, CH-8091 Zurich, Switzerland.
authors.forename: Marco
authors.initials: M
authors.lastname: Prinz
authors.forename: Fabio
authors.initials: F
authors.lastname: Montrasio
authors.forename: Michael A
authors.initials: MA
authors.lastname: Klein
authors.forename: Petra
authors.initials: P
authors.lastname: Schwarz
authors.forename: Josef
authors.initials: J
authors.lastname: Priller
authors.forename: Bernhard
authors.initials: B
authors.lastname: Odermatt
authors.forename: Klaus
authors.initials: K
authors.lastname: Pfeffer
authors.forename: Adriano
authors.initials: A
authors.lastname: Aguzzi
mesh_terms: D000818:Animals; D015703:Antigens, CD / Q000235:genetics; D002678:Chimera; D020566:Dendritic Cells, Follicular / Q000473:pathology*; D006801:Humans; D008198:Lymph Nodes / Q000378:metabolism* / Q000473:pathology*; D053259:Lymphotoxin beta Receptor; D008233:Lymphotoxin-alpha / Q000235:genetics / Q000378:metabolism; D053308:Lymphotoxin-beta; D008565:Membrane Proteins / Q000172:deficiency / Q000235:genetics; D051379:Mice; D018345:Mice, Knockout; D017096:Prion Diseases / Q000209:etiology* / Q000473:pathology / Q000503:physiopathology; D011328:Prions / Q000378:metabolism* / Q000472:pathogenicity*; D018124:Receptors, Tumor Necrosis Factor / Q000172:deficiency / Q000235:genetics; D047888:Receptors, Tumor Necrosis Factor, Type I; D014409:Tumor Necrosis Factor-alpha / Q000172:deficiency / Q000235:genetics
chemical_list: D015703:Antigens, CD; C505886:LTB protein, human; C505697:LTBR protein, human; C505887:Ltb protein, mouse; C505699:Ltbr protein, mouse; D053259:Lymphotoxin beta Receptor; D008233:Lymphotoxin-alpha; D053308:Lymphotoxin-beta; D008565:Membrane Proteins; D011328:Prions; D018124:Receptors, Tumor Necrosis Factor; D047888:Receptors, Tumor Necrosis Factor, Type I; D014409:Tumor Necrosis Factor-alpha