2006 — 2010 |
Kong, Qingzhong |
R01Activity Code Description: To support a discrete, specified, circumscribed project to be performed by the named investigator(s) in an area representing his or her specific interest and competencies. |
Assessing the Transmissibility of Cwd to Humans @ Case Western Reserve University
DESCRIPTION (provided by applicant): Chronic wasting disease (CWD), the prion disease in cervids (deer and elk), is widespread in North America. The cervid population is huge (approximately 22 million) and venison consumption very significant in USA. The fast spreading CWD is hard to contain, and it may pose a serious threat to human health if it is transmissible to humans, even at a low rate. This proposal will use transgenic (Tg) mouse models to answer three critical questions pertinent to the potential dangers posed by CWD to humans: Can CWD be transmitted to humans directly (Aim 1)? Can CWD be transmitted to humans after passage through secondary hosts (cattle or sheep) (Aim 2)? Has CWD transmission to humans already occurred (Aim 3)? The ultimate goals are to define the risks of direct and indirect CWD transmission to humans and to establish a surveillance program to monitor for human subjects infected by CWD prions. Research Design: For Aims 1 and 2, humanized and cervidized Tg mice will be intracerebrally (i.e.) inoculated with brain homogenates either from human subjects with sporadic Creutzfeldt-Jakob disease (CJD) or from CWD-affected animals including: Rocky Mountain elk, mule deer, white-tail deer, cattle, and sheep;sheep scrapie will also be inoculated as a control. The inoculated animals will then be monitored and compared for the transmission rate, incubation time, neurological symptoms, accumulation and distribution of PrP-Sc, and the glycoforms and conformational stability of PrP-Sc before and after passage in the Tg mice. Secondary transmissions will be done to examine for asymptomatic carriers of prion infectivity. Oral transmissions will be performed for CWD isolates that demonstrated infectivity in humanized Tg mice after i.e. inoculation. For Aim 3, cervidized Tg mice will be i.e. inoculated with brain homogenates from CJD subjects who had consumed venison from CWD endemic areas as well as from sporadic CJD subjects not exposed to CWD. The prion infectivity liters in the brain homogenates will be determined for all involved CJD subjects, and the same infectivity dose will be used for inoculation. A statistically significant higher transmission efficiency of prions from "CWD-exposed" CJD subjects than that of the sporadic CJD subjects unexposed to CWD will suggest that the "CWD-exposed" subject likely acquired his CJD from CWD.
|
1 |
2007 — 2011 |
Kong, Qingzhong |
P01Activity Code Description: For the support of a broadly based, multidisciplinary, often long-term research program which has a specific major objective or a basic theme. A program project generally involves the organized efforts of relatively large groups, members of which are conducting research projects designed to elucidate the various aspects or components of this objective. Each research project is usually under the leadership of an established investigator. The grant can provide support for certain basic resources used by these groups in the program, including clinical components, the sharing of which facilitates the total research effort. A program project is directed toward a range of problems having a central research focus, in contrast to the usually narrower thrust of the traditional research project. Each project supported through this mechanism should contribute or be directly related to the common theme of the total research effort. These scientifically meritorious projects should demonstrate an essential element of unity and interdependence, i.e., a system of research activities and projects directed toward a well-defined research program goal. |
Animal Core @ Case Western Reserve University |
1 |
2015 — 2018 |
Kong, Qingzhong |
R01Activity Code Description: To support a discrete, specified, circumscribed project to be performed by the named investigator(s) in an area representing his or her specific interest and competencies. |
Cervid to Human Prion Transmission @ Case Western Reserve University
? DESCRIPTION (provided by applicant): Prion disease is transmissible and invariably fatal. Chronic wasting disease (CWD) is the prion disease affecting deer, elk and moose, and it is a widespread and expanding epidemic affecting 22 US States and 2 Canadian provinces so far. CWD poses the most serious zoonotic prion transmission risks in North America because of huge venison consumption (>6 million deer/elk hunted and consumed annually in the USA alone), significant prion infectivity in muscles and other tissues/fluids from CWD-affected cervids, and usually high levels of individual exposure to CWD resulting from consumption of the affected animal among often just family and friends. However, we still do not know whether CWD prions can infect humans in the brain or peripheral tissues or whether clinical/asymptomatic CWD zoonosis has already occurred, and we have no essays to reliably detect CWD infection in humans. We hypothesize that: (1) The classic CWD prion strain can infect humans at low levels in the brain and peripheral lymphoid tissues; (2) The cervid-to-human transmission barrier is dependent on the cervid prion strain and influenced by the host (human) prion protein (PrP) primary sequence; (3) Reliable essays can be established to detect CWD infection in humans; and (4) CWD transmission to humans has already occurred. We will test these hypotheses in 4 Aims using transgenic (Tg) mouse models and complementary in vitro approaches. Aim 1 will prove that the classical CWD strain may infect humans in brain or peripheral lymphoid tissues at low levels by conducting systemic bioassays in a set of humanized Tg mouse lines expressing common human PrP variants using a number of CWD isolates at varying doses and routes. Experimental human CWD samples will also be generated for Aim 3. Aim 2 will test the hypothesis that the cervid-to-human prion transmission barrier is dependent on prion strain and influenced by the host (human) PrP sequence by examining and comparing the transmission efficiency and phenotypes of several atypical/unusual CWD isolates/strains as well as a few prion strains from other species that have adapted to cervid PrP sequence, utilizing the same panel of humanized Tg mouse lines as in Aim 1. Aim 3 will establish reliable essays for detection and surveillance of CWD infection in humans by examining in details the clinical, pathological, biochemical and in vitro seeding properties of existing and future experimental human CWD samples generated from Aims 1-2 and compare them with those of common sporadic human Creutzfeldt-Jakob disease (sCJD) prions. Aim 4 will attempt to detect clinical CWD-affected human cases by examining a significant number of brain samples from prion-affected human subjects in the USA and Canada who have consumed venison from CWD-endemic areas utilizing the criteria and essays established in Aim 3. The findings from this proposal will greatly advance our understandings on the potential and characteristics of cervid prion transmission in humans, establish reliable essays for CWD zoonosis and potentially discover the first case(s) of CWD infection in humans.
|
1 |
2016 — 2017 |
Kong, Qingzhong Safar, Jiri G. Zou, Wen-Quan [⬀] |
R21Activity Code Description: To encourage the development of new research activities in categorical program areas. (Support generally is restricted in level of support and in time.) |
Accessing Transmissibility and Diagnostic Marker of Skin Prions. @ Case Western Reserve University
? DESCRIPTION (provided by applicant): The fatal, transmissible animal and human prion diseases are characterized by the deposition in the brain of a proteinase K (PK)-resistant infectious prion protein (PrPSc), an isoform derived from the cellular protein (PrPC) through misfolding. A definitive antemortem diagnosis is virtually impossible for most patients because of the difficulty in obtaining the brain tissues by biopsy. Recently, PrPSc has been reported to be detected in the skin of experimentally or naturally scrapie-infected animals (Thomzig et al., 2007). Consistent with this finding, we have observed PK-resistant PrP in the skin of a patient with variant Creutzfeldt-Jakob disease (vCJD), an acquired form of human prion disease caused by bovine prion (Notari et al., 2010). Unexpectedly, our latest preliminary study identified two types of PK-resistant PrP molecules [with gel mobility similar to the PrPSc types 1 and 2 from the brain of sporadic CJD (sCJD)] in the fibroblast cells extracted from the skin of clinical sCJD patients and asymptomatic subjects carrying PrP mutations linked to familial CJD (fCJD). We also detected PrPSc in the skin of humanized transgenic (Tg) mice inoculated intracerebrally with a human prion. Moreover, prion infectivity has been observed in the skin of infected greater kudu (Cunningham et al., 2004) and a murine prion inoculated to mice via skin scarification can not only propagate in the skin, but also spread to the brain to cause prion disease (Wathne et al., 2012). We hypothesize that the skin of patients with prion disease harbors prion infectivity and the presence of PK-resistant PrP in the skin is a novel diagnostic marker for preclinical CJD patients. To test the hypotheses, we propose to (1) determine prion infectivity of the skin- derived fibroblasts and skin of sCJD patients and asymptomatic PrP-mutation carriers using humanized Tg mouse bioassay, (2) to pinpoint the earliest stage at which PrPSc becomes detectable in the skin of prion- infected Tg mice, and (3) to detect PrPSc in the skin of various human prion diseases, using conventional as well as highly sensitive RT-QuIC assays for both (2) and (3). If successful, our proposal may not only help prevent potential transmission of human prion diseases but also enable definitive and less intrusive antemortem diagnosis of prion diseases. Finally, knowledge generated from this study may also enhance our understanding of other neurodegenerative diseases such as Alzheimer's disease.
|
1 |
2018 — 2020 |
Kong, Qingzhong Zou, Wen-Quan [⬀] |
R01Activity Code Description: To support a discrete, specified, circumscribed project to be performed by the named investigator(s) in an area representing his or her specific interest and competencies. |
Role of Skin Prions in Disease Transmission and Diagnostic Testing of Human Prion Disease @ Case Western Reserve University
ABSTRACT Prions (or PrPSc) are the causal agents of fatal transmissible prion diseases including sporadic Creutzfeldt-Jakob disease (sCJD, the most common human prion disease) in humans as well as scrapie, mad cow disease and chronic wasting disease in animals. sCJD is transmissible via medical or surgical procedures due to contamination by abundant infectious prions in the brain of patients. Notably, some epidemiological studies have also associated sCJD risk with non-neurosurgeries but experimental evidence for such a link is lacking. sCJD is currently incurable. At the onset of clinical symptoms, permanent brain damages already occurred. The absence of less invasive early diagnostic tests for the disease can result in missing the critical window for future treatments, and low brain autopsy rate due to cultural constraints prevents the surveillance of sCJD that is essential for effective prevention of iatrogenic sCJD transmissions. Our recent study using the highly sensitive real-time quaking-induced conversion (RT- QuIC) assay and humanized transgenic (Tg) mice-based bioassay revealed that the skin of sCJD patients harbors infectious prions (Orrú et al., 2017). Our new preliminary results further indicate that skin PrPSc is detectable by both RT-QuIC and serial protein misfolding cyclic amplification (sPMCA) assays even at the asymptomatic stage in a prion-infected animal model. We hypothesize that skin PrPSc can be both a source of iatrogenic prion transmission and a biomarker for preclinical/premortem/postmortem diagnostic testing of prion diseases. To test for the hypothesis, the following four Aims will be pursued: (1) to quantitate infectivity of skin prions from sCJD patients, (2) to pinpoint the distribution of PrPSc within the skin, (3) to evaluate the potential of skin PrPSc as the source of iatrogenic transmission, and (4) to validate skin PrPSc as a biomarker for diagnosis of prion diseases. We expect that the proposed study will not only shed light on the potential risk of human-to-human sCJD transmission via skin prions but also establish alternative preclinical/premortem/postmortem diagnostic assays for prion diseases. Moreover, new knowledge generated from this study may apply to much more common neurodegenerative diseases such as Alzheimer?s and Parkinson?s diseases where the disease-specific misfolded proteins have been observed in the skin of respective patients.
|
1 |