Exposure Risk of Chronic Wasting Disease in Humans

PMCA screening of retropharyngeal lymph nodes in white-tailed deer and comparisons with ELISA and IHC

Chronic wasting disease (CWD) is a prion disease affecting cervids. CWD diagnosis is conducted through enzyme-linked immunosorbent assay (ELISA) and immunohistochemistry (IHC) in retropharyngeal lymph nodes. Unfortunately, these techniques have limited sensitivity against the biomarker (CWD-prions). Two in vitro prion amplification techniques, real-time quaking-induced conversion (RT-QuIC) and protein misfolding cyclic amplification (PMCA), have shown promise in detecting CWD-prions in tissues and bodily fluids. Recent studies have demonstrated that RT-QuIC yields similar results compared to ELISA and IHC. Here, we analyzed 1003 retropharyngeal lymph nodes (RPLNs) from Texas white-tailed deer. PMCA detected CWD at a higher rate compared to ELISA/IHC, identified different prion strains, and revealed the presence of CWD-prions in places with no previous history. These findings suggest that PMCA exhibits greater sensitivity than current standard techniques and could be valuable for rapid and strain-specific CWD detection.

Human prion diseases and the prion protein - what is the current state of knowledge?

Prion diseases and the prion protein are only partially understood so far in many aspects. This explains the continued research on this topic, calling for an overview on the current state of knowledge. The main objective of the present review article is to provide a comprehensive up-to-date presentation of all major features of human prion diseases bridging the gap between basic research and clinical aspects. Starting with the prion protein, current insights concerning its physiological functions and the process of pathological conversion will be highlighted. Diagnostic, molecular, and clinical aspects of all human prion diseases will be discussed, including information concerning rare diseases like prion-associated amyloidoses and Huntington disease-like 1, as well as the question about a potential human threat due to the transmission of prions from prion diseases of other species such as chronic wasting disease. Finally, recent attempts to develop future therapeutic strategies will be addressed.

Hunting-Based Food Donation Programs: Program Characteristics Across the US

OBJECTIVE

Hunting-based food donation (HBFD) programs are unique food assistance programs because they provide under-resourced food bank participants with a quality protein source. This study aimed to summarize the characteristics of US HBFD programs and discuss the potential barriers and considerations to use or access these programs.

METHODS

Data were collected via a web search for HBFD programs within all 50 states and the District of Columbia.

RESULTS

Most states were found to have an active program (n = 36), whereas 14 states and the District of Columbia do not have programs. Game donation amounts vary greatly between states, and funding for these programs typically comes from a government agency.

CONCLUSIONS AND IMPLICATIONS

Hunting-based food donation can positively impact the food security and nutritional status of vulnerable populations. Nutrition professionals can aid in promoting awareness of these programs and provide nutrition education around wild game nutrition, safety, and food preparation.

Body-first Parkinson's disease and variant Creutzfeldt-Jakob disease - similar or different?

In several neurodegenerative disorders, proteins that typically exhibit an α-helical structure misfold into an amyloid conformation rich in β-sheet content. Through a self-templating mechanism, these amyloids are able to induce additional protein misfolding, facilitating their propagation throughout the central nervous system. This disease mechanism was originally identified for the prion protein (PrP), which misfolds into PrP^Sc in a number of disorders, including variant Creutzfeldt-Jakob disease (vCJD) and bovine spongiform encephalopathy (BSE). More recently, the prion mechanism of disease was expanded to include other proteins that rely on this self-templating mechanism to cause progressive degeneration, including α-synuclein misfolding in Parkinson's disease (PD). Several studies now suggest that PD patients can be subcategorized based on where in the body misfolded α-synuclein originates, either the brain or the gut, similar to patients developing sporadic CJD or vCJD. In this review, we discuss the human and animal model data indicating that α-synuclein and PrP^Sc misfolding originates in the gut in body-first PD and vCJD, and summarize the data identifying the role of the autonomic nervous system in the gut-brain axis of both diseases.

Selective Breeding for Disease-Resistant PRNP Variants to Manage Chronic Wasting Disease in Farmed Whitetail Deer

Chronic wasting disease (CWD) is a fatal transmissible spongiform encephalopathy (TSE) of cervids caused by a misfolded variant of the normal cellular prion protein, and it is closely related to sheep scrapie. Variations in a host's prion gene, PRNP, and its primary protein structure dramatically affect susceptibility to specific prion disorders, and breeding for PRNP variants that prevent scrapie infection has led to steep declines in the disease in North American and European sheep. While resistant alleles have been identified in cervids, a PRNP variant that completely prevents CWD has not yet been identified. Thus, control of the disease in farmed herds traditionally relies on quarantine and depopulation. In CWD-endemic areas, depopulation of private herds becomes challenging to justify, leading to opportunities to manage the disease in situ. We developed a selective breeding program for farmed white-tailed deer in a high-prevalence CWD-endemic area which focused on reducing frequencies of highly susceptible PRNP variants and introducing animals with less susceptible variants. With the use of newly developed primers, we found that breeding followed predictable Mendelian inheritance, and early data support our project's utility in reducing CWD prevalence. This project represents a novel approach to CWD management, with future efforts building on these findings.

Tackling prion diseases: a review of the patent landscape

Introduction: Prion diseases are a class of rare and fatal neurodegenerative diseases for which no cure is currently available. They are characterized by conformational conversion of cellular prion protein (PrP^C) into the disease-associated 'scrapie' isoform (PrP^Sc). Under an etiological point of view, prion diseases can be divided into acquired, genetic, and idiopathic form, the latter of which are the most frequent.Areas covered: Therapeutic approaches targeting prion diseases are based on the use of chemical and nature-based compounds, targeting either PrP^C or PrP^Sc or other putative player in pathogenic mechanism. Other proposed anti-prion treatments include passive and active immunization strategies, peptides, aptamers, and PrP^C-directed RNA interference techniques. The treatment efficacy has been mainly assessed in cell lines or animal models of the disease testing their ability to reduce prion accumulation.Expert opinion: The assessed strategies focussing on the identification of an efficient anti-prion therapy faced various issues, which go from permeation of the blood brain barrier to immunological tolerance of the host. Indeed, the use of combinatory approaches, which could boost a synergistic anti-prion effect and lower the potential side effects of single treatments and may represent an extreme powerful and feasible way to tackle prion disease.