Wednesday, September 04, 2019

Deciphering the BSE-type specific cell and tissue tropisms of atypical (H and L) and classical BSE

Deciphering the BSE-type specific cell and tissue tropisms of atypical (H and L) and classical BSE 

Anne Balkema-Buschmann, Grit Priemer, Reiner Ulrich, Romano Strobelt, Bob Hills & Martin H. Groschup To cite this article: Anne Balkema-Buschmann, Grit Priemer, Reiner Ulrich, Romano Strobelt, Bob Hills & Martin H. Groschup (2019) Deciphering the BSE-type specific cell and tissue tropisms of atypical (H and L) and classical BSE, Prion, 13:1, 160-172, DOI: 10.1080/19336896.2019.1651180 To link to this article: https://doi.org/10.1080/19336896.2019.1651180

ABSTRACT 

After the discovery of two atypical bovine spongiform encephalopathy (BSE) forms in France and Italy designated H- and L-BSE, the question arose whether these new forms differed from classical BSE (C-BSE) in their pathogenesis. Samples collected from cattle in the clinical stage of BSE during an intracranial challenge study with L- and H-BSE were analysed using biochemical and histological methods as well as in a transgenic mouse bioassay. Our results generally confirmed what had been described for C-BSE to be true also for both atypical BSE forms, namely the restriction of the pathological prion protein (PrPSc) and BSE infectivity to the nervous system. However, analysis of samples collected under identical conditions from both atypical H- and L-BSE forms allowed us a more precise assessment of the grade of involvement of different tissues during the clinical end stage of disease as compared to C-BSE. One important feature is the involvement of the peripheral nervous and musculoskeletal tissues in both L-BSE and H-BSE affected cattle. We were, however, able to show that in H-BSE cases, the PrPSc depositions in the central and peripheral nervous system are dominated by a glial pattern, whereas a neuronal deposition pattern dominates in L-BSE cases, indicating differences in the cellular and topical tropism of both atypical BSE forms. As a consequence of this cell tropism, H-BSE seems to spread more rapidly from the CNS into the periphery via the glial cell system such as Schwann cells, as opposed to L-BSE which is mostly propagated via neuronal cells.

Conclusions The PrPSc and infectivity distribution patterns of atypical BSE seem to be generally similar to that known for classical BSE, with a clear restriction to the central and peripheral nervous and the musculoskeletal system. Taken our results together, we postulate distinct cell tropisms and propagation pathways for both atypical BSE forms, which both have their putative location of origin in the central nervous system. While L-BSE strongly affects the neurons of the CNS followed by the PNS, H-BSE initially affects CNS and PNS glia and only at later stages spreads to neurons. This is in sharp contrast to what is well acknowledged for C-BSE, which is the uptake of the infectious agent in the digestive tract, followed by a neuronal transport to the CNS.


IBNC BSE TSE Prion mad cow disease

 ***however in 1 C-type challenged animal, Prion 2015 Poster Abstracts S67 PrPsc was not detected using rapid tests for BSE.

***Subsequent testing resulted in the detection of pathologic lesion in unusual brain location and PrPsc detection by PMCA only.

*** IBNC Tauopathy or TSE Prion disease, it appears, no one is sure ***

Posted by Terry S. Singeltary Sr. on 03 Jul 2015 at 16:53 GMT


WEDNESDAY, AUGUST 15, 2018 

The agent of H-type bovine spongiform encephalopathy associated with E211K prion protein polymorphism transmits after oronasal challenge


THURSDAY, AUGUST 08, 2019 

Raccoons accumulate PrPSc after intracranial inoculation with the agents of chronic wasting disease (CWD) or transmissible mink encephalopathy (TME) but not atypical scrapie


FRIDAY, JULY 26, 2019 

Chronic Wasting Disease in Cervids: Implications for Prion Transmission to Humans and Other Animal Species


MONDAY, FEBRUARY 25, 2019

MAD DOGS AND ENGLISHMEN BSE, SCRAPIE, CWD, CJD, TSE PRION A REVIEW 2019


WEDNESDAY, JULY 31, 2019 

The agent of transmissible mink encephalopathy passaged in sheep is similar to BSE-L


Terry S. Singeltary Sr.

SUNDAY, SEPTEMBER 1, 2019 

FDA Reports on VFD Compliance

Before and after the current Veterinary Feed Directive (VFD) rules took full effect in January, 2017, the FDA focused primarily on education and outreach to help feed mills, veterinarians and producers understand and comply with the requirements. Since then, FDA has gradually increased the number of VFD inspections and initiated enforcement actions when necessary.


MONDAY, AUGUST 26, 2019 

Creutzfeldt Jakob Disease CJD, TSE, Prion, Surveillance Update August 2019


Is the re-use of sterilized implant abutments safe enough? (Implant abutment safety)
 
Mª Angeles Sánchez-Garcés 1 , Marta Jorba 2 , Joan Ciurana 3 , Miguel Vinas 4 , Mª Teresa Vinuesa 5

snip...

 Despite only a few laboratories in the world are undertaking experimental work with prions, notably that of Stanley B. Prusiner (Nobel Prize in Physiology or Medicine, 1997), the work has led to several major concerns (14). 

The first and most relevant in the current context is that prions need to be completely inactivated using harsher conditions than those used against bacteria and viruses. To ensure prion inactivation, the thermal sterilization should be combined with chemical treatment. It would appear that procedures used for routine sterilization of surgical instruments cannot inactivate prions (15,16), which already led to the development of new and more stringent recommendations for reprocessing instruments and these should eventually be applied to abutments (17). This has been reinforced by the discovery that prions that are responsible for bovine spongiform encephalitis (BSE) can be up to 1 million times more difficult to inactivate than the most commonly used hamster prions; thus, one cannot exclude the possibility that human prions are also much more resistant than the laboratory prions (10). These recommendations are based on conventional autoclaving (121ºC) combined with chemical attack; this may be achieved by autoclaving in the presence of 1 M sodium hydroxide, or by soaking in 2% bleach for 1 h. Such treatments are extremely corrosive and may cause irreversible damage to the surface of abutments (18). Prevalence of asymptomatic Creutzfeldt-Jakob disease (CJD) in UK population in people born from 1941 to 1985 is 1:2000 and prion iatrogenic transmission (blood transfusions, organ transplants and surgical instrumentation) is therefore possibility. Another source of prions could be bovine bone substitutes used widely for bone regeneration after or simultaneously to the dental implant placement. These materials keep some proteins, their manufacturing processes are not guaranty to the inactivation of the prion, and in consequence, Kim et al. (19) suggest abolishing the use of bovine bone. 

The presence of organic carbon reported in our study means that organic material originating in the patient is adhered to the surface and, subsequently, the presence of prions cannot be ruled out. 

In conclusion, we believe that, despite costs, the practice of reusing implant abutments should be abandoned, since it cannot be demonstrated to be safe enough.

Further studies trying to identify the source of the organic carbon adhered in the abutments are needed. In addition, it is worth elucidating if there could be any safe procedure to effectively remove all the organic material present in the titanium surfaces of the reused healing abutments.

http://www.medicinaoral.com/medoralfree01/aop/22967.pdf

HUNTERS, CWD TSE PRION, THIS SHOULD A WAKE UP CALL TO ALL OF YOU GUTTING AND BONING OUT YOUR KILL IN THE FIELD, AND YOUR TOOLS YOU USE...

* 1: J Neurol Neurosurg Psychiatry 1994 Jun;57(6):757-8
Transmission of Creutzfeldt-Jakob disease to a chimpanzee by electrodes contaminated during neurosurgery.
Gibbs CJ Jr, Asher DM, Kobrine A, Amyx HL, Sulima MP, Gajdusek DC.
Laboratory of Central Nervous System Studies, National Institute of
Neurological Disorders and Stroke, National Institutes of Health,
Bethesda, MD 20892.
Stereotactic multicontact electrodes used to probe the cerebral cortex of a middle aged woman with progressive dementia were previously implicated in the accidental transmission of Creutzfeldt-Jakob disease (CJD) to two younger patients. The diagnoses of CJD have been confirmed for all three cases. More than two years after their last use in humans, after three cleanings and repeated sterilisation in ethanol and formaldehyde vapour, the electrodes were implanted in the cortex of a chimpanzee. Eighteen months later the animal became ill with CJD. This finding serves to re-emphasise the potential danger posed by reuse of instruments contaminated with the agents of spongiform encephalopathies, even after scrupulous attempts to clean them.
PMID: 8006664 [PubMed - indexed for MEDLINE]

SATURDAY, MARCH 16, 2019 

Medical Devices Containing Materials Derived from Animal Sources (Except for In Vitro Diagnostic Devices) Guidance for Industry and Food and Drug Administration Staff Document issued on March 15, 2019 Singeltary Submission



Terry S. Singeltary Sr.












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