NR AMDN
AU Wadsworth,J.D.F.; Joiner,S.; Hill,A.F.; Campbell,T.A.; Desbruslais,M.; Luthert,P.J.; Collinge,J.
TI Tissue distribution of protease resistant prion protein in variant Creutzfeldt-Jakob disease using a highly sensitive immunoblotting assay
QU Lancet 2001 Jul 21; 358(9277): 171-80
KI Lancet. 2001 Jul 21;358(9277):164-5. PMID: 11476826 Lancet. 2002 Mar 2;359(9308):801. PMID: 11888628
PT journal article
AB BACKGROUND: Variant Creutzfeldt-Jakob disease (vCJD) has a pathogenesis distinct from other forms of human prion disease: disease-related prion protein (PrPsc) is readily detectable in lymphoreticular tissues. Quantitation of risk of secondary transmission, and targeting of risk reduction strategies, is limited by lack of knowledge about relative prion titres in these and other peripheral tissues, the unknown prevalence of preclinical vCJD, and a transmission barrier which limits the sensitivity of bioassay. We aimed to improve immunoblotting methods for high sensitivity detection of PrPsc to investigate the distribution of PrPsc in a range of vCJD tissues. METHODS: We obtained tissues at necropsy from four patients with neuropathologically confirmed vCJD and from individuals without neurological disease. Tissues were analysed by sodium phosphotungstic acid precipitation of PrPsc and western blotting using high sensitivity enhanced chemiluminescence. FINDINGS: We could reliably detect PrPsc in the equivalent of 50 nL 10% vCJD brain homogenate, with a maximum limit of detection equivalent to 5 nl. PrPsc could be detected in tissue homogenates when present at concentrations 10(4)-10(5) fold lower than those reported in brain. Tonsil, spleen, and lymph node were uniformly positive for PrPsc at concentrations in the range of 0.1-15% of those found in brain: the highest concentrations were consistently seen in tonsil. PrPsc was readily detected in the retina and proximal optic nerve of vCJD eye at levels of 2.5 and 25%, respectively of those found in brain. Other peripheral tissues studied were negative for PrPsc with the exception of low concentrations in rectum, adrenal gland, and thymus from a single patient with vCJD. vCJD appendix and blood (Buffy coat fraction) were negative for PrPsc at this level of assay sensitivity. INTERPRETATION: We have developed a highly sensitive immunoblot method for detection of PrPsc in vCJD tissues that can be used to provide an upper limit on PrPsc concentrations in peripheral tissues, including blood, to inform risk assessment models. Rectal and other gastrointestinal tissues should be further investigated to assess risk of iatrogenic transmission via biopsy instruments. Ophthalmic surgical instruments used in procedures involving optic nerve and the posterior segment of the eye, in particular the retina, might represent a potential risk for iatrogenic transmission of vCJD. Tonsil is the tissue of choice for diagnostic biopsy and for population screening of surgical tissues to assess prevalence of preclinical vCJD infection within the UK and other populations.
MH Animal; Blotting, Western/methods; Chemiluminescence; Creutzfeldt-Jakob Syndrome/epidemiology/*metabolism/pathology/transmission; Great Britain/epidemiology; Human; Iatrogenic Disease; Phosphotungstic Acid; PrPsc Proteins/*analysis/isolation & purification; Prevalence; Risk Factors; Sensitivity and Specificity; Support, Non-U.S. Gov't; Surgical Instruments; Tissue Distribution; Tonsil/chemistry
AD MRC Prion Unit and Department of Neurogenetics, Imperial College School of Medicine at St Mary's, Norfolk Place, W2 1PG, London, UK
SP englisch
PO England