Prion cell tropism significantly varies among animal species, depending on both the agent strain and host-specific factors. For
example, prions show high lymphotropism in scrapie infected sheep and in vCJD, but little, if any, in sCJD or BSE. In particular, the BSE
strain is associated with significant PrP-res accumulation in tonsils, spleen and appendix in humans, whereas, it is largely confined to the
nervous system in infected cattle. So, it appears that, at least in the case of BSE and vCJD, host properties can influence the accumulation of the infectious agent in lymphoid organs.
Given that the normal cellular prion protein (PrPc), is sine qua non for PrP-res formation and the development of TSE, it appears reasonable to hypothesize that tissue-specific PrPc properties may represent one of the host factors influencing the cell tropism of the infectious agent in human or bovine.
Characterization of bovine and human cellular prion protein expressed
Characterization of bovine and human cellular prion protein expressed
in the central nervous system and in lymphoid organs
in the central nervous system and in lymphoid organs
V. Defaweux1, S. Capellari2, S. Stramiello2, N. Antoine3, G. Dorban1, C. Demonceau1, O. Jolois1, E. Heinen1 and P. Parchi2.
1Dpt of Morphology and Immunology, Institute of Human Histology, Faculty of Medecine, University of Liège, Belgium–www.ulg.ac.be/histohum. 2Department of Neurological Sciences, Faculty of Medicine, University of Bologna, Italy.
3Laboratoy of Animal Histology, Department of Morphology and Pathology, Faculty of Veterinary Medecine, University of Liège, Belgium.
SAF32
SAF60
PrPc glycoform ratios are
significantly different between cerebellum and medulla in bovine and human.
Only the unglycosylated PrPc is distributed like wise in medulla and in the cerebellum of bovine and human.
Western blot analysis to compare the ratio of PrPc glycoforms expressed
in the CNS of bovine and human
PrPc forms expressed in bovine CNS
Western blot analysis of truncated
The expression of truncated forms of PrPc (i.e. 21 and 18 kDa PrPc) is also significantly heterogenous according to the brain region investigated.
Western blot analysis to compare the PrPc glycoform ratios and the truncated PrPc forms expressed
in bovine lymphoid tissues
in bovine lymhpoid cells
SAF32 SAF60 SAF32 Isolation of PrPc expressing follicular dendritic cells (FDC) FDC ultrastructure SAF32+ FDC
PrPc is highly glycosylated in spleen and in lymphoid follicles isolated from bovine lymphoid tissues as well as in their FDC and lymphocytes. After deglycosylation, a novel PrPc truncated form with a relative molecular mass of about 25 kDa was detected in bovine lymphoid organs beside the typical 18 and 21 kDa forms.
Western blot analysis to compare the PrPc glycoform ratios and the
truncated PrPc forms expressed in human lymphoid tissues
Our results highlight variation in
the profile expression of PrPc in
peripheral and central tissues of
bovine
and
human.
Such
differences
may
have
an
implication for PrPc function and
may represent critical factors
influencing the accumulation of the
infectious agent in these areas.
SAF32
No difference in WB PrPc profile was seen in follicles, lymphocytes and FDC of human tissues
Immune PrPc is highly glycosylated and, after deglycosylation, the 25 kDa is also
