PrPCWD lymphoid cell targets in early and advanced chronic wasting disease of mule deer

Up to 15% of free-ranging mule deer in northeastern Colorado and southeastern Wyoming, USA, are afflicted with a prion disease, or transmissible spongiform encephalopathy (TSE), known as chronic wasting disease (CWD). CWD is similar to a subset of TSEs including scrapie and variant Creutzfeldt¿Jakob disease in which the abnormal prion protein isoform, PrPCWD, accumulates in lymphoid tissue. Experimental scrapie studies have indicated that this early lymphoid phase is an important constituent of prion replication interposed between mucosal entry and central nervous system accumulation. To identify the lymphoid target cells associated with PrPCWD, we used triple-label immunofluorescence and high-resolution confocal microscopy on tonsils from naturally infected deer in advanced disease. We detected PrPCWD primarily extracellularly in association with follicular dendritic and B cell membranes as determined by frequent co-localization with antibodies against membrane bound immunoglobulin and CD21. There was minimal co-localization with cytoplasmic labels for follicular dendritic cells (FDC). This finding could indicate FDC capture of PrPCWD, potentially in association with immunoglobulin or complement, or PrPC conversion on FDC. In addition, scattered tingible body macrophages in the germinal centre contained coarse intracytoplasmic aggregates of PrPCWD, reflecting either phagocytosis of PrPCWD on FDC processes, apoptotic FDC or B cells, or actual PrPCWD replication within tingible body macrophages. To compare lymphoid cell targets in early and advanced disease, we also examined: (i) PrPCWD distribution in lymphoid cells of fawns within 3 months of oral CWD exposure and (ii) tonsil biopsies from preclinical deer with naturally acquired CWD. These studies revealed that the early lymphoid cellular distribution of PrPCWD was similar to that in advanced disease, i.e. in a pattern suggesting FDC association. We conclude that in deer, PrPCWD accumulates primarily extracellularly and associated with FDCs and possibly B cells ¿ a finding which raises questions as to the cells responsible for pathological prion productio

Cellular distribution of the prion protein in palatine tonsils of mule deer (Odocoileus hemionus) and Rocky Mountain elk (Cervus elaphus nelsoni)

Chronic wasting disease (CWD) is a transmissible spongiform encephalopathy (TSE) that affects members of the Cervidae family, including deer (Odocoileus spp.), elk (Cervus Canadensis spp.), and moose (Alces alces spp.). While CWD is a neurodegenerative disease, lymphoid accumulation of the abnormal isoform of the prion protein (PrPSc) is detectable early in the course of infection. It has been shown that a large portion of the PrPSc lymphoid accumulation in infected mule deer takes place on the surface of follicular dendritic cells (FDCs). In mice, FDC expression of PrPC has been shown to be essential for PrPSc accumulation. FDCs have been shown to normally express high levels of PrPC in mice and humans but this has not been examined in natural hosts for CWD. We used double immunofluorescent labeling and confocal microscopy to determine the PrPC expression characteristics of B and T lymphocytes as well as FDCs in palatine tonsils of CWD-negative mule deer and elk. We detected substantial PrPC colocalization with all cellular phenotypic markers used in this study, not just with FDC phenotypic markers

Deer and reforestation in the Pacific Northwest

Deer and reforestation interact mainly during regeneration after wildfire or logging. In interior forests, browsing by mule deer often damages conifer seedlings planted on winter or transitional ranges. In the Douglas-fir region, numbers of blacktailed deer increase dramatically after forests are logged or burned, in response to improved forage supplies. Here, browsing on planted stock in clearcuts lowers forest productivity by reducing growth rates and occasionally contributes to plantation failures. Browsing damage can be controlled by fences or cages, but costs are prohibitive. Amelioration of damage by black-tailed deer could be achieved through long-range planning for concurrent deer and timber harvests, with hunting pressure directed to areas where logging promotes more deer. Thus, more deer can be made available to hunters and browsing damage to reforestation lessened. Such programs would require complete cooperation among resource managers and an intensive, well-planned effort to sell them to both customers and critics

Seri dictionary: Mammals

A subset of the Seri bilingual dictionary includes terms referring to mammals. This version includes English glosses in addition to the Spanish glosses, and an English-to-Seri reversal. In addition, extensive footnotes are included which provide information from Edward Moser\u27s field notes relating to the Seri knowledge of mammals. Other excerpts from the Seri dictionary have been published in the 1997, 1999 and 2000 Work Papers. The complete dictionary was published in 2005 and updated in 2010. The second edition is available here: mexico.sil.org/resources/archives/4282

Parallelisms and Contrasts in the Diverse Ecologies of the Anaplasma phagocytophilum and Borrelia burgdorferi Complexes of Bacteria in the Far Western United States.

Anaplasma phagocytophilum and Borrelia burgdorferi are two tick-borne bacteria that cause disease in people and animals. For each of these bacteria, there is a complex of closely related genospecies and/or strains that are genetically distinct and have been shown through both observational and experimental studies to have different host tropisms. In this review we compare the known ecologies of these two bacterial complexes in the far western USA and find remarkable similarities, which will help us understand evolutionary histories and coadaptation among vertebrate host, tick vector, and bacteria. For both complexes, sensu stricto genospecies (those that infect humans) share a similar geographic range, are vectored mainly by ticks in the Ixodes ricinus-complex, utilize mainly white-footed mice (Peromyscus leucopus) as a reservoir in the eastern USA and tree squirrels in the far west, and tend to be generalists, infecting a wider variety of vertebrate host species. Other sensu lato genospecies within each complex are generally more specialized, occurring often in local enzootic cycles within a narrow range of vertebrate hosts and specialized vector species. We suggest that these similar ecologies may have arisen through utilization of a generalist tick species as a vector, resulting in a potentially more virulent generalist pathogen that spills over into humans, vs. utilization of a specialized tick vector on a particular vertebrate host species, promoting microbe specialization. Such tight host-vector-pathogen coupling could also facilitate high enzootic prevalence and the evolution of host immune-tolerance and bacterial avirulence

Gypsum Cave revisited: Faunal and taphonomic analysis of a Rancholabrean-to-Holocene fauna in southern Nevada

Gypsum Cave, near Las Vegas, Nevada, was excavated in 1930, yielding a Rancholabrean-to-Holocene mammalian fauna intermixed with many human artifacts. The bone assemblage, which is now housed at the Los Angeles County Museum of Natural History, contains burned and fractured bones with conspicuous grooves that have never before been studied. The objectives of this study are to (1) identify and describe the Gypsum Cave fauna, (2) interpret the taphonomy of the fauna to test the hypothesis that Gypsum Cave represents a site of interaction between Pleistocene animals and Paleo-Indians, and (3) use the Gypsum Cave fauna to better characterize the Pleistocene paleoecology of Southern Nevada. The methods include: identifying the species present; determining their abundance in the cave; determining the age of the fauna; determining the spatial distribution of the bones; analyzing the fractures and surficial features of the bones; and examining the micromorphology of the burned bone surfaces. These scanning electron microscope (SEM) analyses indicate that Gypsum Cave does not represent a site of Late Pleistocene human butchery, but rather a Late Pleistocene predator\u27s lair that was later inhabited and overprinted by humans in the Holocene

Measuring Trace Element Concentrations in Artiodactyl Cannonbones using Portable X-Ray Fluorescence

Artiodactyl bones are the most common faunal remains found in Washington prehistoric archaeology sites, but they are often too fragmented to accurately identify a family, genus, or species. Traditional faunal analysis can only organize unidentifiable bone fragments into size class, and chemical methods often require the destruction of bone samples. In this thesis research, I tested a new, nondestructive faunal analysis technique using portable X-ray fluorescence (pXRF) to measure trace element concentrations in comparative collection and archaeological bone samples. Using cannonbones from five different artiodactyl species, I collected trace element data from 50 comparative collection specimens and 18 archaeological specimens previously identified to species. I used a Random Forest classification analysis to predict the family and species of modern comparative and archaeological specimens based on collected trace element data. Species identification accuracy was 70% for modern specimens and 22% for archaeological specimens, while family identification accuracy was 82% for modern specimens and 67% for archaeological specimens. These results suggest that identification pXRF method used in this thesis is promising, but would require further work to be definitive

A new early occurrence of Cervidae in North America from the Miocene-Pliocene Ellensburg Formation in Washington, USA

A new fossil cervid from the Craig’s Hill locality of the Miocene-Pliocene Ellensburg Formation in the State of Washington, USA, may be one of the oldest fossil deer yet found in North America, underlying a date of 4.9 Ma ± 0.1 Ma. This mandible fragment with m2, m3, and associated p2 has a size that does not distinguish it from Bretzia pseudalces, Odocoileus hemionus, or Capreolus constantini, and distinguishes it from Eocoileus gentryorum and Odocoileus lucasi only in having a thinner p2. A strong paraconid on the p2, and ectostylids and cingulids on the m2 and m3 link it most strongly with Bretzia pseudalces, but these are also intermittently present in Odocoileus hemionus. Because of the close geographic and temporal proximity of Bretzia pseudalces in the Ringold Formation, and its shared morphology with Bretzia, we are tentatively assigning this specimen to cf. Bretzia

Carpals and tarsals of mule deer, black bear and human: an osteology guide for the archaeologist

Existing osteological literature often lacks descriptions and illustrations of the smaller elements, such as hand and foot bones, of animals commonly found in the archaeological record. Black bear (Ursus americanus) and mule deer (Odocoileus hemionus) are both cosmopolitan species and important resources for indigenous peoples, resulting in their widespread presence in faunal assemblages. Additionally, the carpal and tarsal elements of these two mammalian taxa can be difficult to distinguish from human elements because of their similarities in size and shape. Proper identification of faunal and human remains is paramount to responsible cultural resource management (CRM). This thesis presents a textual and photographic osteological guide of black bear and mule deer carpals and tarsals and provides the means for distinguishing these elements from their human counterparts