CWD infected deer B cells and platelets harbor prion infectivity in the blood
Posted Mar 19 2010 11:25am
J. Virol. doi:10.1128/JVI.02169-09 Copyright (c) 2010, American Society for Microbiology and/or the Listed Authors/Institutions. All Rights Reserved.
B cells and platelets harbor prion infectivity in the blood of CWD–infected deer.
Candace K. Mathiason, Jeanette Hayes-Klug, Sheila A. Hays, Jenny Powers, David A. Osborn, Sallie J. Dahmes, Karl V. Miller, Robert J. Warren, Gary L. Mason, Glenn C. Telling, Alan C. Young, and Edward A. Hoover* Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO, USA; National Park Service, Fort Collins, CO, USA; Warnell School of Forestry and Natural Resources, University of Georgia, Athens, GA, USA; WASCO Inc., Monroe, GA, USA; University of Kentucky Medical Center, Lexington, KY, USA; South Dakota State University, Brookings, SD, USA
* To whom correspondence should be addressed. Email: Edward.Hoover@ColoState.EDU.
Substantial evidence for prion transmission via blood transfusion exists for many TSE diseases. Determining which cell phenotype(s) are responsible for trafficking infectivity has important implications in understanding dissemination of prions as well as their detection and elimination from blood products. We used bioassay studies in the native white-tailed deer and transgenic cervidized mice to determine: (a) if chronic wasting disease (CWD) blood infectivity is associated with the cellular vs. the cell-free/plasma fraction of blood, and (b) in particular if B cell (MAb2-104+), platelet (CD41/61+) or CD14+ monocyte blood cell phenotypes harbor infectious prions. All four deer transfused with the blood mononuclear cell fraction from CWD+ donor deer became PrPCWD-positive by 19 months post inoculation, whereas none of the deer (0/4) inoculated with the same source cell-free plasma developed prion infection. All deer (4/4) injected with B cells, and 3/4 deer receiving platelets from CWD+ donor deer became PrPCWD-positive in as little as 6 months post inoculation, whereas none (0/4) deer receiving blood CD14+ monocytes developed evidence of CWD infection (immunohistochemistry and western blot analysis) after 19 months of observation. Results of the Tg(cerPrP)mouse bioassays mirrored those in the native cervid host. These results indicate that CWD blood infectivity is cell-associated and suggest a significant role for B cells and platelets in trafficking CWD infectivity in vivo and support earlier tissue-based studies associating putative follicular B cells with PrPCWD. Localization of CWD infectivity with leukocyte subpopulations may aid in enhancing sensitivity of blood-based diagnostic assays for CWD and other TSEs.
In Confidence - Perceptions of unconventional slow virus diseases of animals in the USA - APRIL-MAY 1989 - G A H Wells
3. Prof. A Robertson gave a brief account of BSE. The US approach was to accord it a very low profile indeed. Dr. A Thiermann showed the picture in the ''Independent'' with cattle being incinerated and thought this was a fanatical incident to be avoided in the US at all costs. BSE was not reported in the USA.
CWD occurred principally in two locations, this one at Sybille and in a similar faccility at Fort Collins, Colorado, some 120 miles southwest. It was estimated that in total probably 60-70 cases of CWD have occurred.
It was difficult to gain a clear account of incidence and temporal sequence of events (-this presumably is data awaiting publication - see below) but during the period 1981-1984, 10-15 cases occurred at the Sybille facility.
The moribidity amongst mule deer in the facilities ie. those of the natural potentially exposed group has been about 90% with 100% mortality.
Spraker suggested an interesting explanation for the occurrence of CWD. The deer pens at the Foot Hills Campus were built some 30-40 years ago by a Dr. Bob Davis. At or abut that time, allegedly, some scrapie work was conducted at this site. When deer were introduced to the pens they occupied ground that had previously been occupied by sheep.