Name: procedures for identifying infectious prions after passage through the digestive system of an avian species
Uploaded: 2013-11-06T21:30:00
Description: Watch this Scientific Journal Video about Procedures for Identifying Infectious Prions After Passage Through the Digestive System of an Avian Species at JoVE.com

We would like to thank S. Werner for providing the crows used in this study and USDA, APHIS, WS, NWRC animal care staff for animal care and monitoring. Mention or use of a product does not imply USDA endorsement. Funding for this study was provided by USDA, APHIS, Veterinary Services.

Our protocol is adapted from one we previously published7. All procedures involving animals were approved by the Institutional Animal Care and Use Committee of the United States Department of Agriculture (USDA), Animal and Plant Health Inspection Service (APHIS), Wildlife Services (WS), National Wildlife Research Center (NWRC).
1. Crow Gavaging
<ol>
	<li>Estimate passage time of &#39;pseudo brain material&#39; through the alimentary tract of American crows.
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		<li>Mix 5 ml of...

<ol>
	<li>Prusiner, S. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Novel+proteinaceous+infectious+particles+cause+scrapie.">Novel proteinaceous infectious particles cause scrapie.</a> Science. 216 (4542), 136-144 (1982).</li><li>Miller, M. W., Williams, E. S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Epizootiology+of+chronic+wasting+disease+in+free-ranging+cervids+in+Colorado+and+Wyoming.">Epizootiology of chronic wasting disease in free-ranging cervids in Colorado and Wyoming.</a> Journal of Wildlife Diseases. 36 (4), 676-690 (2000).</li><li>Miller, M. W., Williams, E. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Horizontal+prion+transmission+in+mule+deer.">Horizontal prion transmission in mule deer.</a> Nature. 425 (6953), 35-36 (2003).</li><li>Sigurdson, C. J., Adriano, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Chronic+Wasting+Disease.">Chronic Wasting Disease.</a> Biochimica et Biophysica Acta. 1772 (6), 610-618 (2007).</li><li>Miller, M. W., Williams, E. S., Hobbs, N. T., Wolfe, L. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Environmental+sources+of+prion+transmission+in+mule+deer.">Environmental sources of prion transmission in mule deer.</a> Emerging Infectious Diseases. 10 (6), 1003-1006 (2004).</li><li>Mathiason, C. K., Hays, S. A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Infectious+prions+in+pre-clinical+deer+and+transmission+of+chronic+wasting+disease+solely+by+environmental+exposure.">Infectious prions in pre-clinical deer and transmission of chronic wasting disease solely by environmental exposure.</a> PLoS ONE. 4 (6), e5916 (2009).</li><li>VerCauteren, K. C., Pilon, J. L., Nash, P. B., Phillips, G. E., Fischer, J. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Prion+remains+infectious+after+passage+through+digestive+system+of+American+crows+(Corvus+crachyrhunchos).">Prion remains infectious after passage through digestive system of American crows (Corvus crachyrhunchos).</a> PLoS ONE. 7 (10), e45774 (2012).</li><li>Imran, M., Mahmood, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+overview+of+animal+prion+diseases.">An overview of animal prion diseases.</a> Virology Journal. 8 (493), (2011).</li><li>Watts, J. C., Balachandran, A., Westaway, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+expanding+universe+of+prion+disease.">The expanding universe of prion disease.</a> PLoS PATHOGENS. 2 (3), e26 (2006).</li><li>Bruce, M. E., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Transmissions+to+mice+indicate+that+'new+variant'+CJD+is+caused+by+the+BSE+agent.">Transmissions to mice indicate that 'new variant' CJD is caused by the BSE agent.</a> Nature. 389 (6650), 498-501 (1997).</li><li>Ryder, S., Dexter, G., Bellworty, S., Tongue, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Demonstration+of+lateral+transmission+of+scrapie+between+sheep+kept+under+natural+conditions+using+lymphoid+tissue+biopsy.">Demonstration of lateral transmission of scrapie between sheep kept under natural conditions using lymphoid tissue biopsy.</a> Research in Veterinary Science. 76 (2004), 211-217 (2004).</li><li>Collinge, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+risk+of+prion+zoonoses.">The risk of prion zoonoses.</a> Science. 335 (6067), 411-413 (2012).</li><li>Beringue, V., Vilotte, J. L., Laude, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Prion+agent+diversity+and+species+barrier.">Prion agent diversity and species barrier.</a> Veterinary Research. 39 (47), (2008).</li><li>Harrington, R. D., Baszler, T., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+species+barrier+limits+transmission+of+chronic+wasting+disease+to+mink+(Mustela+vison).">A species barrier limits transmission of chronic wasting disease to mink (Mustela vison).</a> The Journal of General Virology. 89 (4), 1086-1096 (2008).</li><li>Wisniewski, H. M., Sigurdarson, S., Rubenstein, R., Kascsak, R. J., Carp, R. I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mites+as+vectors+for+scrapie.">Mites as vectors for scrapie.</a> Lancet. 347 (9008), 1114 (1996).</li><li>Post, K., Riesner, D., Walldorf, V., Mehlhorn, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Fly+larvae+and+pupae+as+vectors+for+scrapie.">Fly larvae and pupae as vectors for scrapie.</a> Lancet. 354 (9194), 1969-1970 (1999).</li><li>Matthews, D., Cooke, B. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+potential+for+transmissible+spongiform+encephalopathies+in+non-ruminant+livestock+and+fish.">The potential for transmissible spongiform encephalopathies in non-ruminant livestock and fish.</a> Revue Scientifique Et Technique-Office International Des Epizooties. 22 (1), 283-296 (2003).</li><li>Jennelle, C. S., Samuel, M. D., Nolden, C. A., Berkley EA, . <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Deer+carcass+decomposition+and+potential+scavenger+exposure+to+chronic+wasting+disease.">Deer carcass decomposition and potential scavenger exposure to chronic wasting disease.</a> Journal of Wildlife Management. 73 (5), 655-662 (2009).</li><li>Scherbel, C., Pichner, R., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Degradation+of+scrapie+associated+prion+protein+(PrPSc)+by+the+gastrointestinal+microbiota+of+cattle.">Degradation of scrapie associated prion protein (PrPSc) by the gastrointestinal microbiota of cattle.</a> Veterinary Research. 37 (5), 695-703 (2006).</li><li>Jeffrey, M., Gonza&#225;lez, L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Transportation+of+prion+protein+across+the+intestinal+mucosa+of+scrapie+susceptible+and+scrapie-resistant+sheep.">Transportation of prion protein across the intestinal mucosa of scrapie susceptible and scrapie-resistant sheep.</a> Journal of Pathology. 209 (1), 4-14 (2006).</li><li>Nicholson, E. M., Richt, J. A., Rasmussen, M. A., Hamir, A. N., Lebepe-Mazur, S., Horst, R. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Exposure+of+sheep+scrapie+brain+homogenate+to+rumen-simulating+conditions+does+not+result+in+a+reduction+of+PrP(Sc)+levels.">Exposure of sheep scrapie brain homogenate to rumen-simulating conditions does not result in a reduction of PrP(Sc) levels.</a> Letters in Applied Microbiology. 44 (6), 631-636 (2007).</li><li>Motes C, M. a. l. u. q. u. e. r. d. e., Grassi, J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Excretion+of+BSE+and+scrapie+prions+in+stools+from+murine+models.">Excretion of BSE and scrapie prions in stools from murine models.</a> Veterinary Microbiology. 131 (1-2), 205-211 (2008).</li><li>Kruger, D., Thomzig, A., Lenz, G., Kampf, K., McBride, P., Beekes, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Faecal+shedding,+alimentary+clearance+and+intestinal+spread+of+prions+in+hamsters+fed+with+scrapie.">Faecal shedding, alimentary clearance and intestinal spread of prions in hamsters fed with scrapie.</a> Veterinary Research. 40 (1), 4 (2009).</li><li>Mathiason, C. K., Nalls, A. V., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Susceptibility+of+domestic+cats+to+chronic+wasting+disease.">Susceptibility of domestic cats to chronic wasting disease.</a> Journal of Virology. 87 (4), 1947-1956 (2013).</li><li>Bjorndal, K. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Flexibility+of+digestive+responses+in+two+generalist+herbivores,+the+tortoises+Geochelone+carbonaria+and+Geochelone+denticulate.">Flexibility of digestive responses in two generalist herbivores, the tortoises Geochelone carbonaria and Geochelone denticulate.</a> Oecologia. 78 (3), 317-321 (1989).</li><li>Clark, R. G., Gentle, G. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Estimates+of+grain+passage+time+in+captive+mallards.">Estimates of grain passage time in captive mallards.</a> Canadian Journal of Zoology. 68 (11), 2275-2279 (1990).</li><li>Dierenfeld, E. S., Koontz, F. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Feed+intake,+digestion+and+passage+of+proboscis+monkey+(Nasalis+larvatus)+in+captivity.">Feed intake, digestion and passage of proboscis monkey (Nasalis larvatus) in captivity.</a> Primates. 33 (3), 399-405 (1992).</li><li>Thompson, A. K., Samuel, M. D., Van Deelen, T. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Alternative+feeding+strategies+and+potential+disease+transmission+in+Wisconsin+white-tailed+deer.">Alternative feeding strategies and potential disease transmission in Wisconsin white-tailed deer.</a> Journal of Wildlife Management. 72 (2), 416-421 (2008).</li><li>Pulford, B., Spraker, T. A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Detection+of+PrPCWD+in+feces+from+naturally+exposed+Rocky+Mountain+elk+(Cervus+elaphus+nelsoni)+using+protein+misfolding+cyclic+amplification.">Detection of PrPCWD in feces from naturally exposed Rocky Mountain elk (Cervus elaphus nelsoni) using protein misfolding cyclic amplification.</a> Journal of Wildlife Diseases. 48 (2), 425-433 (2012).</li><li>Hicks, R. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Guano+deposition+in+an+Oklahoma+crow+roost.">Guano deposition in an Oklahoma crow roost.</a> Condor. 81 (3), 247-250 (1979).</li><li>Aldous, S. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Winter+habits+of+crows+in+Oklahoma.">Winter habits of crows in Oklahoma.</a> Journal of Wildlife Management. 73 (4), 290-295 (1944).</li></ol>

We demonstrate a procedure to document passage of PrPRes material through the digestive system of crows. We used conventional methods to determine if crows have the ability to translocate PrPRes material to disease-free geographic areas. Others have evaluated resistance of PrPRes to ruminant19-21 and rodent22,23 digestive fluids, both of which failed to eliminate it. Future application of these techniques should be applied to other carnivores24 as they cou...

Transmissible spongiform encephalopathies (TSE) are fatal infectious neurodegenerative disorders that affect wildlife, domestic animals, and humans. The infectious agent of TSE diseases appears to be misfolded or pathogenic isoforms (PrPRes) of prion proteins1. Animal TSE diseases include chronic wasting disease (CWD) in mule deer (Odocoileus hemionus), white-tailed deer (Odocoileus virginianus), elk (Cervus elaphus), and moose (Alces alces); scrapie in sheep and goats; bovine spongiform encephalopathy (BSE) in domestic cattle; transmissible mink encephalopathy in farmed mink; feline spongiform encephalopathy in cats; exotic ungulate spongiform encephalopathy in exotic zoo ruminates of the family Bovidae; and spongiform encephalopathy in nonhuman primates8. The single human TSE disease, variant Creutzfeldt-Jakob disease, is rare and thought to be acquired by consuming PrPRes-contaminated food9. Similarly, BSE can infect humans if contaminated beef is consumed10. Of all the TSE diseases, scrapie and CWD are the only two with self-sustaining epidemics and sources for infection are presumed to be from animal to animal2,3,11 as well as from environmental sources4-6. Research suggests that most TSE diseases require notable extended incubation periods from natural exposure events of PrPRes material to manifestation of clinical signs2-4,6,8 and apparent species barriers minimize, but do not eliminate the potential for, interspecies transmission12-14.
Identifying mechanisms for the spread of infectious prion (PrPRes) material is extremely important for answering questions about how TSE diseases move across the landscape. Experimental investigations have suggested that insects15,16, poultry and pigs17, and American crows (Corvus brachyrhynchos)7,18 are passive carriers or dispersers of PrPRes material. Passage of PrPRes material through the digestive system of crows has recently been documented, demonstrating the role they may play in dispersal of TSE diseases7. These results make it plausible that crows, a scavenger, could encounter, consume, and transport infectious material via feces deposition, to disease-free areas.
The procedures we demonstrate here were used to document passage of PrPRes material through the digestion system of crows and will greatly facilitate the application of these methods to other scavenger and carnivore species-specific models in related future research. In this study conventional methods were used to investigate an unconventional means of trafficking PrPRes material, which could contribute to the spread and overall burden of PrPRes material.

<table border="0" cellpadding="0" cellspacing="0" width="545">
	<tbody>
		<tr height="43">
			<td height="43" style="height:43px;width:217px;">RML Chandler strain mouse-adapted scrapie</td>
			<td style="width:112px;">Rocky Mountain Laboratories</td>
			<td style="width:137px;"></td>
			<td style="width:79px;"></td>
		</tr>
		<tr height="43">
			<td height="43" style="height:43px;width:217px;">RC57BL/6 mice</td>
			<td style="width:112px;">Hilltop Lab Animals</td>
			<td style="width:137px;"></td>
			<td style="width:79px;"></td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;width:217px;">American crows</td>
			<td style="width:112px;">wild captured</td>
			<td style="width:137px;"></td>
			<td style="width:79px;"></td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;width:217px;">Pen/Strep</td>
			<td>Invitrogen</td>
			<td style="width:137px;">15140-122</td>
			<td style="width:79px;"></td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;width:217px;">Phosphate buffered Saline</td>
			<td style="width:112px;">Invitrogen</td>
			<td style="width:137px;">70011-044</td>
			<td style="width:79px;"></td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;width:217px;">Sonicator</td>
			<td>Misonix</td>
			<td style="width:137px;"></td>
			<td style="width:79px;"></td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;width:217px;">Proteinase-K solution</td>
			<td style="width:112px;">Roche</td>
			<td align="right" style="width:137px;">3115887001</td>
			<td style="width:79px;"></td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;width:217px;">Loading buffer</td>
			<td style="width:112px;">Invitrogen</td>
			<td style="width:137px;">NP0007 and 0009</td>
			<td style="width:79px;"></td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;width:217px;">Bis-tris SDS PAGE 12% gel</td>
			<td style="width:112px;">Invitrogen</td>
			<td style="width:137px;">NP0342</td>
			<td style="width:79px;"></td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;width:217px;">Immobilon PVDF membrane</td>
			<td style="width:112px;">Millipore</td>
			<td style="width:137px;">1SEQ00010</td>
			<td style="width:79px;"></td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;width:217px;">Tween 20</td>
			<td style="width:112px;">Sigma Aldrich</td>
			<td style="width:137px;">P2287</td>
			<td style="width:79px;"></td>
		</tr>
		<tr height="43">
			<td height="43" style="height:43px;width:217px;">Bullet blender homogenizer</td>
			<td style="width:112px;">Braintree Scientific</td>
			<td style="width:137px;">BBX24B</td>
			<td style="width:79px;"></td>
		</tr>
		<tr height="43">
			<td height="43" style="height:43px;width:217px;">2.3 mm Zirconia/silica beads</td>
			<td style="width:112px;">BioSpec Products</td>
			<td style="width:137px;">11079125Z</td>
			<td style="width:79px;"></td>
		</tr>
		<tr height="43">
			<td height="43" style="height:43px;width:217px;">Bar224 anti-PrP monoclonal antibody</td>
			<td style="width:112px;">Cayman Chemical</td>
			<td align="right" style="width:137px;">10009035</td>
			<td style="width:79px;"></td>
		</tr>
		<tr height="43">
			<td height="43" style="height:43px;width:217px;">Superblock</td>
			<td style="width:112px;">Thermo Scientific</td>
			<td align="right" style="width:137px;">37517</td>
			<td style="width:79px;"></td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;width:217px;">chemiluminescent substrate</td>
			<td style="width:112px;">Millipore</td>
			<td style="width:137px;">WBKLS0500</td>
			<td style="width:79px;"></td>
		</tr>
		<tr height="43">
			<td height="43" style="height:43px;width:217px;">G-box gel documentation system</td>
			<td style="width:112px;">Syngene</td>
			<td style="width:137px;"></td>
			<td style="width:79px;"></td>
		</tr>
	</tbody>
</table>

procedures for identifying infectious prions after passage through the digestive system of an avian species

Infectious prion (PrPRes) material is likely the cause of fatal, neurodegenerative transmissible spongiform encephalopathy (TSE) diseases1. Transmission of TSE diseases, such as chronic wasting disease (CWD), is presumed to be from animal to animal2,3 as well as from environmental sources4-6. Scavengers and carnivores have potential to translocate PrPRes material through consumption and excretion of CWD-contaminated carrion. Recent work has documented passage of PrPRes material through the digestive system of American crows (Corvus brachyrhynchos), a common North American scavenger7.
We describe procedures used to document passage of PrPRes material through American crows. Crows were gavaged with RML-strain mouse-adapted scrapie and their feces were collected 4 hr post gavage. Crow feces were then pooled and injected intraperitoneally into C57BL/6 mice. Mice were monitored daily until they expressed clinical signs of mouse scrapie and were thereafter euthanized. Asymptomatic mice were monitored until 365 days post inoculation. Western blot analysis was conducted to confirm disease status. Results revealed that prions remain infectious after traveling through the digestive system of crows and are present in the feces, causing disease in test mice.

The procedures used demonstrate that the digestive system of crows does not eliminate PrPRes infectivity 4 hr after oral gavage of scrapie brain homogenate7. All twenty crows that were gavaged with PrPRes material subsequently transmitted PrPRes material via feces to mice. Diseased mice were identified by manifestation of clinical mouse-scrapie signs and disease confirmation was completed by Western blot analysis.
Investigation of the retention time ...

Watch this Scientific Journal Video about Procedures for Identifying Infectious Prions After Passage Through the Digestive System of an Avian Species at JoVE.com

Procedures for Identifying Infectious Prions After Passage Through the Digestive System of an Avian Species

Scavengers have potential to translocate infectious transmissible spongiform encephalopathy prions in their feces to disease-free areas. We detail methods used to determine if mouse-adapted scrapie prions remain infectious after passage though the digestive tract of American crows (Corvus brachyrhynchos), a common consumer of dead animals.

Infectious prion (PrPRes) material is likely the cause of fatal, neurodegenerative transmissible spongiform encephalopathy (TSE) diseases1. Transmission ...

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Medical imaging using animal models for human diseases has been utilized for decades; however, until recently, medical imaging of diseases induced by ...

Safety Precautions and Operating Procedures in an (A)BSL-4 Laboratory: 3. Aerobiology

Safety Precautions and Operating Procedures in an ABSL-4 Laboratory: 3. Aerobiology

Aerosol or inhalational studies of high-consequence pathogens have recently been increasing in number due to the perceived threat of intentional aerosol ...

Zika Virus Infectious Cell Culture System and the In Vitro Prophylactic Effect of Interferons

Zika Virus Infectious Cell Culture System and the In Vitro Prophylactic Effect of Interferons

Zika Virus (ZIKV) is an emerging pathogen that is linked to fetal developmental abnormalities such as microcephaly, eye defects, and impaired growth. ZIKV ...

Isolating Lymphocytes from the Mouse Small Intestinal Immune System

The intestinal immune system plays an essential role in maintaining the barrier function of the gastrointestinal tract by generating tolerant responses to ...