Under rare circumstances, Aβ seeds can be transferred to people during medical procedures. Researchers have turned up a few cases of tissue transplants or hormones from cadavers triggering amyloidosis in the brains or blood vessels of recipients. But could more common procedures, such as neurosurgeries or blood transfusions, spread proteopathic seeds? In a white paper in the September 16 Lancet Neurology online, a working group of 37 leading experts in the field, led by Bart De Strooper, U.K. Dementia Research Institute at University College London, conclude that existing data for this frightening vision are weak. They found 11 cases where neurosurgery is suspected of having sparked cerebral amyloid angiopathy decades later, and no cases of suspected transmission by blood transfusion.

  • Working group finds little evidence that Aβ seeds are transferred during neurosurgery.
  • Calls for long-term epidemiological study.
  • Recommends neurosurgeons use separate tools for adults and children to minimize risk.

All the researchers agreed that the potential risk is so minuscule that it should not affect a person’s decision about whether to have neurosurgery. For context, about 14 million neurosurgeries are performed worldwide each year, according to the Program in Global Surgery and Social Change at Harvard Medical School (Dewan et al., 2018). “Our recommendation for anyone in need of neurosurgery or blood transfusion is to proceed as planned,” co-first author Elsa Lauwers, KU Leuven, Belgium, told Alzforum. “The potential risk, if any, will be outweighed by the benefit of the procedure.”

Other researchers concur. “The likelihood of transmission of Aβ seeds by neurosurgery or blood transfusion is negligible or very low in my view,” John Trojanowski at the University of Pennsylvania, Philadelphia, wrote to Alzforum. He was not part of the workshop.

Previously, researchers led by John Collinge and Sebastian Brandner at University College London had discovered that human growth hormone extracted from the pituitary glands of cadavers can transfer prion disease and brain amyloidosis to recipients (Sep 2015 news; Dec 2018 news). Collinge and Brandner are co-authors on the white paper. Likewise, co-author Charles Duyckaerts at Hôpital Pitié-Salpêtrière, Paris, as well as other groups, have found that grafts of postmortem dural tissue are associated with early onset amyloid plaques and CAA (Jan 2016 news; Hervé et al., 2018Jan 2019 news). Physicians have stopped using material from cadavers, so this type of transmission is no longer a concern.

More ominously, perhaps, three papers in the last two years have suggested that Aβ seeds could travel from brain to brain by sticking to surgical instruments (Feb 2018 news; Hamaguchi et al., 2019; Giaccone et al., 2019). In most of the 11 reported cases, babies had undergone neurosurgery and developed severe CAA leading to brain hemorrhages in their 30s. These patients had no cognitive impairment, and only rarely developed parenchymal plaques or neurofibrillary tangles.

These case studies generated alarming headlines about the possibility of “transmissible Alzheimer’s” (Dec 2018 Nature; Feb 2019 Scientific American). The working group believes these fears are overblown. “The small number of documented cases and the retrospective nature of these studies preclude conclusions of a causal relationship,” they wrote. That said, they noted that because of the long latency period to CAA after exposure to seeds, additional cases could have been missed.

“Presently the data are not convincing enough that Aβ pathology has been transmitted by neurosurgical instruments,” co-author Mathias Jucker at the German Center for Neurodegenerative Diseases, Tübingen, wrote to Alzforum. Nonetheless, he believes the possibility exists and more investigation is needed.

To settle the issue, Lauwers, co-first author Giovanni Lalli, and colleagues suggest tracking people who have transfusions and neurosurgery early in life to evaluate whether they are more likely to have a neurodegenerative disease decades later. In addition, researchers should check for a history of neurosurgery in people with early onset CAA, noted co-author Stéphane Haïk at Hôpital Pitié-Salpêtrière, Paris.

Some of the authors plan to directly test for the presence of transmissible proteins on surgical tools. They will collect instruments that were used for neurosurgery on AD patients, and assess whether contact with those surfaces can trigger amyloidosis in mouse models of the pathology.

The authors recommend evaluating experimental procedures that might improve detection of proteopathic seeds. Methods that detect protein aggregation, such as the protein-misfolding cyclic-amplification assay and real-time quaking-induced conversion assay, could determine if seeds are present on surgical tools (Dec 2016 news; Sano et al., 2017; Groveman et al., 2018). 

They call on the research community to find better ways of decontaminating equipment. Typical sterilization procedures, such as high temperatures and formaldehyde, are ineffective at removing misfolded proteins and may even stabilize them, but enzymes or other cleaning protocols might work (Edgeworth et al., 2011; Sep 2014 news). Ronald Melki at the French National Center for Scientific Research in Gif–sur–Yvette uses the detergent sodium dodecyl sulfate (SDS) to dissolve aggregates of Aβ42, tau, and α-synuclein from lab equipment, but he notes that the cleaning procedure has to be adapted to the particular polymorph (Fenyi et al., 2018). 

Meanwhile, the authors recommend that neurosurgeons minimize any possible risk by using separate sets of instruments for children and older adults. Many clinics do this already, Lauwers noted. “It’s not a costly measure, and it won’t much change the daily practice in hospitals,” she said. Jucker said his hospital is now paying close attention to this issue.

Blood transfusions appear even safer than neurosurgery, the panel concludes. In one study of 1,465,845 people from Denmark or Sweden who received blood transfusions between 1968 and 2012, the 42,254 who got blood from someone later diagnosed with a neurodegenerative disease had no increased risk of getting the disease, compared to those who received blood from other donors (Edgren et al., 2016). This study was possible because blood banks in Denmark and Sweden store samples from each blood donation and track both donor and recipient health over decades (SCANDAT2 database).

Since there is no test for proteopathic seeds in blood, the authors recommend additional measures to minimize any possible risk to the blood supply. People with a family history of prion disease or an early onset neurodegenerative disorder, as well as anyone who received a dural graft or hormones from a cadaver, should be barred from donating blood. The authors do not recommend a maximum age limit for donors, as this would make it too difficult to maintain the blood supply. Adopting a blood banking system like Sweden and Denmark’s could help determine if there is any increased risk, they added.

Despite the apparent low risk of these medical procedures, the authors still believe caution is warranted. “It seems logical and good practice to adopt a series of proactive safety measures with good cost-to-potential-risk ratio,” they wrote.

They are distributing the white paper to hospitals and blood banks to raise awareness of the issue. “We want to make sure policy makers are well-informed and can make the best decision,” Lauwers said.—Madolyn Bowman Rogers

Comments

  1. The evidence to date is that there may be a very small risk of transmission of pathogenic Aβ in the course of neurosurgical procedures, and that over several decades this can lead to the development of cerebral amyloid angiopathy.

    Neurosurgery carries risks, including infection, hemorrhage, neurological deficits, and epilepsy, and it is contemplated only if the likely benefits clearly outweigh those risks. The minimal additional risk of transmission of pathogenic Aβ should not have any bearing on the advisability of a particular procedure. This would apply whether the neurosurgery was for me, someone else, or my child. The same considerations should apply to decisions regarding blood transfusion.

    The kind of studies the field needs include long-term monitoring (which should include autopsy follow-up studies), particularly after blood transfusion and neurosurgery in early life, so that we can obtain more accurate data on the risk and possible manifestations of Aβ transmission. The studies would also determine whether other aggregation-prone neurodegenerative disease-related proteins, such as tau and α-synuclein, are occasionally transmitted from human to human in the course of neurosurgery or blood transfusion. We also need research to clarify mechanisms and modes of transmission, to develop low-cost, high-throughput assays for transmissible proteins, and to optimize procedures for decontamination of equipment.

  2. Since all brain surgery is a form of brain trauma, and brain trauma is associated with risk for AD, it is not possible to separate out this brain-trauma risk from risk associated with surgical instruments contaminated with CNS pathologies.

  3. I’m not an expert on this precise topic. That said, we have considered this issue here in France and Professor Duyckaerts, myself, and others participated in a scientific committee that was convened on this topic in 2016. I was asked specifically to focus on the risk associated with preparing and handling fibrillar tau, α-synuclein, Aβ, etc. … The fibrils we prepare have prion-like properties and people may know that my lab is among the four in the world that can amplify seeds present in the brains or peripheral tissues of patients.

    The authors of this manuscript are right. We cannot exclude the possibility of transmission through surgical intervention or tissue transplant (blood being a tissue). We cannot exclude either that scientists may be contaminated by the large amounts of fibrils they prepare, and often sonicate, thus generating aerosols, when we can show that those fibrils trigger pathology in animal models upon injection, in particular in the olfactory bulb in the case of α-synuclein. The only way at this stage to determine what might happen is to establish strict traceability. This might not be possible for blood (an industrial process).

    We need strict and validated cleaning procedures for surgical tools. We established such procedures in my lab for labware. We clean and neutralize the fibrils we most often use with the detergent SDS, but the cleaning procedures must be adapted to the polymorph one is using (see Fig. 4 of Fenyi et al., 2018). In addition, although it is not particularly convenient, we established fragmentation procedures using sonication that do not generate aerosols and we handle large amounts of fibrils in BSL-2 to BSL-3 labs. This is stated in our papers (Fenyi et al., 2019Van der Perren et al., 2020). I know this is complicated, but this is also the only way to bring the risk to close to zero.

    In general terms, what is useful is the use of disposable tools when possible and limiting the possible propagation among humans by avoiding tissues donated by people who possibly are incubating the disease. We might not be able to bring the risk to zero, but most often the interventions we are discussing here (surgical intervention, organ transplant, including blood) are performed because the person is at risk of dying. Therefore I, as a citizen, consider the risk we take to be acceptable.

    References:

    . Assessment of the efficacy of different procedures that remove and disassemble alpha-synuclein, tau and A-beta fibrils from laboratory material and surfaces. Sci Rep. 2018 Jul 17;8(1):10788. PubMed.

    . Detection of alpha-synuclein aggregates in gastrointestinal biopsies by protein misfolding cyclic amplification. Neurobiol Dis. 2019 Sep;129:38-43. Epub 2019 May 9 PubMed.

    . The structural differences between patient-derived α-synuclein strains dictate characteristics of Parkinson's disease, multiple system atrophy and dementia with Lewy bodies. Acta Neuropathol. 2020 Jun;139(6):977-1000. Epub 2020 Apr 30 PubMed.

  4. As underlined in this paper, to date, the risk of transmission associated with Aβ pathology during neurosurgery remains uncertain. Data are limited and inconclusive. In my opinion, they are by far insufficient to delay or forgo any necessary neurosurgery regardless of the patient’s age.

    Epidemiological studies will be key to estimate this risk. Prospective cohorts of patients with a medical history of neurosurgery in early life would be useful, keeping in mind that time duration between exposure and potentially transmitted CAA is several decades. A surveillance of early onset CAA with a retrospective checking of prior history of neurosurgery would provide informative data.

    In recent decades, in light of the risk associated with CJD prion transmission, various improvements have been made for prion detection and, notably in neurosurgery, prion decontamination. In France, the systematic use of 134°C autoclaving procedures and inactivating solutions efficient against prions has been adopted.

    Expansion of detection procedures from the prion field to other proteopathic seeds is in progress and it would be probably helpful to assess how procedures designed to eliminate CJD transmission risk are efficient against other amyloids. Developing fundamental research to better understand the nature and the mechanisms of propagation of prions, other proteopathic seeds, and their different strains is a central issue

  5. How strange that researchers focus on the patients, who get one brain operation each. Largely ignored is a possible risk to neurosurgeons, who all day are exposed to brain after brain, accompanied by glove nicks, sharps penetrations, and cautery smoke plumes.

    Three years ago I called attention to a provocative report that neurosurgeons seemed to have excessive deaths from Alzheimer's compared to other physicians. How long must we wait for epidemiologists and biostatisticians to dig into such data to establish whether transmissibility is occurring?

    See "It’s Time to Find the 'Alzheimer’s Germ,'” Norins LC. ALZgerm.org/whitepaper. 

    References:

    . Cause-specific mortality among neurosurgeons. J Neurosurg. 2010 Sep;113(3):474-8. PubMed.

  6. Lauwers and colleagues present a helpful synopsis of the potential risk of human transmission of β-amyloid pathology by contaminated neurosurgical equipment and blood transfusions. The authors point out that the current evidence to support iatrogenic transmission is weak and often hampered by small cohort sizes, retrospective evaluations, and long disease incubation periods. Despite the low probability of transmission, the authors appropriately suggest adopting proactive safety measures, such as using separate surgical tools for adults and children, enzyme-based detergents for instrument decontamination, and developing large-scale and long-term epidemiological studies to track disease incidence in those who have undergone high-risk medical interventions.

    The authors also propose employing molecular tools, such as protein misfolding cyclic amplification or RT-QuIC, to aid in detection of proteopathic seeds from potentially contaminated materials. In addition to these methods, I would also propose using cell-based seeding assays such as those previously described for tau and α-synuclein (Holmes et al., 2014). These assays are highly sensitive, robust, and facile, and could be adopted by labs with access to cell culture and flow cytometry workflows. Future generations of these cell-based assays may enable multiplexed molecular fingerprinting to identify specific strains across multiple proteopathic seed types simultaneously. If iatrogenic transmission is indeed occurring, correlating specific strains with disease subtypes could offer highly compelling evidence for proteopathic seed propagation. Finally, as we build registries for long-term patient monitoring, it would be fascinating to know if host factors, such as genetic background, could lead to increased risk of acquiring and propagating proteopathic seeds.

    In the meantime, I agree with the authors that I would not discourage my patients from undergoing beneficial neurosurgical interventions or blood transfusions. However, as we build patient registries and develop new tools for detection of contaminated materials, we will be even better equipped to counsel our patients appropriately.

    References:

    . Proteopathic tau seeding predicts tauopathy in vivo. Proc Natl Acad Sci U S A. 2014 Oct 14;111(41):E4376-85. Epub 2014 Sep 26 PubMed.

  7. There are ample clearing mechanisms in the body for proteins such as amyloid. We know that there is a turnover of amyloid, so to speculate that there may be some detrimental effect from tiny amounts of amyloid in the body is stretching the likelihood of probabilities beyond the imaginable. In addition, we should remember that a number of clinical trials in AD patients showed no improvement even though the levels of amyloid in their brains and CSF had been reduced significantly.

  8. The paper by Lauwers et al. is a timely reminder of the transmissible properties of amyloid fibrils. This is a story that started in the 1960s with the observations of the systemic amyloid researchers using experimental models of what is now known as AA amyloid, an acute-phase protein of hepatic origin. Their original work preceded the discovery of the transmissible PrP protein in CJD/scrapie. Several groups found that systemic amyloidosis could be “enhanced” by injection of a factor derived from and inoculated into sensitized mice (Hultgren et al., 1967; Ranlov, 1967; Werdelin and Ranlov, 1968; Shirahama et al., 1969). Many years later, this “amyloid-enhancing factor” was identified as the AA protein itself, but uncertainty still persists over the conformation of the transmissible subunit: β-rich oligomer or β-stranded amyloid protofibril or fibril (Westermark, 2005; Tasaki et al., 2010). 

    In the 1970s, much effort was expended on comparing the transmissibility of CJD with AD and other neurodegenerative diseases. We came to the conclusion that AD was not transmissible, at least not with clinical and pathological kinetics similar to the replication of the PrP protein as now recognized in CJD (Goudsmit et al., 1980). Of course, those were the days before Aβ, and the more sensitive assays using immunocytochemistry and quantitative immuno-assays for the replication of low levels of Aβ in experimentally inoculated animals were yet to be applied. It would still be worth going back and re-examining these AD-inoculated animals’ brain sections for the amplification of Aβ.

    Which brings us to the 1990s. We described a case of presumptive iatrogenic CJD five years after a dura mater graft (Simpson et al., 1996). The late Donald Simpson was the doyen of Australian neurosurgery, and a close friend of Carleton Gajdusek. I (Colin L. Masters) noted in the pathological report that this case was “unusual” because in addition to the spongiform change of CJD, this 56-year-old recipient also showed abundant Aβ plaques and congophilic angiopathy in the absence of neurofibrillary tangles. This may have been the first example of what we are now debating: transmissible human-to-human Aβ induced by seeding from the dura mater. The article was published in a relatively obscure Australian journal, and probably went unnoticed by the rest of the research community.

    By coincidence, we have now published (today) a paper on the finding that the incidence of intracerebral hemorrhage may be increased in Australian cadaveric pituitary hormone recipients (Alnakhli et al., 2020). Yes, it’s in the same obscure Australian journal as the Simpson et al., 1996, paper. But since it directly addresses the issues that Lauwers et al. raise in The Lancet, maybe it will reach a wider audience. An odds ratio of 2.77 for intracerebral hemorrhage in human cadaveric hormone recipients is worth noting and needs replication in a more robust manner.

    References:

    . Experimental amyloidosis in isogeneic x-irradiated recipients of sensitized spleen tissue. Am J Pathol. 1967 Jun;50(6):943-55. PubMed.

    . The adoptive transfer of experimental mouse amyloidosis by intravenous injections of spleen cell extracts from casein-treated syngeneic donor mice. Acta Pathol Microbiol Scand. 1967;70(3):321-35. PubMed.

    . Amyloidosis induced in mice by transplantation of casein-sensitized and not-sensitized spleen cells. Acta Pathol Microbiol Scand. 1968;72(1):13-22. PubMed.

    . Heterologous transfer of amyloid--human to mouse. Proc Soc Exp Biol Med. 1969 Feb;130(2):516-9. PubMed.

    . Aspects on human amyloid forms and their fibril polypeptides. FEBS J. 2005 Dec;272(23):5942-9. PubMed.

    . Transmission of circulating cell-free AA amyloid oligomers in exosomes vectors via a prion-like mechanism. Biochem Biophys Res Commun. 2010 Oct 1;400(4):559-62. Epub 2010 Aug 31 PubMed.

    . Evidence for and against the transmissibility of Alzheimer disease. Neurology. 1980 Sep;30(9):945-50. PubMed.

    . Iatrogenic Creutzfeldt-Jakob disease and its neurosurgical implications. J Clin Neurosci. 1996 Apr;3(2):118-23. PubMed.

    . Intra-cerebral haemorrhage but not neurodegenerative disease appears over-represented in deaths of Australian cadaveric pituitary hormone recipients. Journal of Clinical Neuroscience, November 2020

  9. In their comment above, Colin L. Masters and Steven J. Collins rightfully pointed to a report from 1996 of what most likely is the first case of Aβ transmission after a graft of human dura mater material (Simpson et al., 1996). We want to acknowledge here that this report takes precedence over the 74 cases of suspected iatrogenic transmission of amyloid β pathology we recently reviewed.

    In another, very recent publication, Colin L. Masters, Steven J. Collins, and colleagues (Alnakhli et al., 2020) screened the death certificates of 184 individuals who received human cadaveric pituitary hormone treatment before 1985. They found that deaths listed as from "intra-cerebral haemorrhage" were significantly increased compared to the standard population, whereas there was no evidence to support increased deaths from non-prion neurodegenerative diseases such as AD or PD (consistent with previous report from John Trojanowski and colleagues, Irwin et al., 2013). These findings confirms the conclusion from our working group that AD itself is not transmissible iatrogenically.

    References:

    . Evaluation of potential infectivity of Alzheimer and Parkinson disease proteins in recipients of cadaver-derived human growth hormone. JAMA Neurol. 2013 Apr;70(4):462-8. PubMed.

    . Iatrogenic Creutzfeldt-Jakob disease and its neurosurgical implications. J Clin Neurosci. 1996 Apr;3(2):118-23. PubMed.

  10. We commend the careful wording in the new paper by Steve Collins and colleagues that reports a significant increase in intracerebral hemorrhage (potentially related to amyloid-β cerebral amyloid angiopathy (CAA)) in a group of c-hGH recipients, but no significant increase in standardized mortality from neurodegenerative diseases other than iatrogenic Creutzfeldt-Jakob disease (iCJD, Alnakhli et al., 2020). 

    Collins and colleagues were cautious to point out the limitations of their study. They note the small sample size and that, like the earlier study by Irwin et al. (Irwin et al., 2013), it was based only on death certificates; living c-hGH recipients (over 90 percent) potentially manifesting the diseases of interest were not ascertained. They considered their findings tentative and supported the need for more detailed epidemiological studies, and we certainly agree.

    With respect to the last comment from Elsa Lauwers and Bart De Strooper, we think it premature to make definitive statements on the lack of transmissibility of Alzheimer’s disease. At the workshop, there was near consensus on the human transmission of amyloid-β pathology and the disease CAA. We agree that human transmission of AD has not yet been confirmed (Jaunmuktane et al., 2015; Purro et al., 2018) and expect that, in any case, it would likely be confined to specialized medical and surgical interventions.

    However, absence of evidence is not evidence of absence. Given the accumulating evidence in experimental models and new human data we recommend renewed efforts in AD epidemiology and long-term monitoring of individuals who may have been inadvertently inoculated with amyloid-β and other proteopathic seeds.

    The parallels, both scientifically and historically, with understanding prion disease are important to emphasize. CJD is universally accepted to be a transmissible dementia, although it is not contagious. However, in reality, only around 1 percent of recognized cases have a known environmentally acquired (“transmitted”) etiology. The large majority of human prion disease cases are sporadic, and nearly all the rest are earlier-onset inherited forms.

    It is also important to appreciate the extraordinary incubation periods possible in acquired human prion diseases. We know from study of kuru, as well as iCJD, that these can exceed five decades (Collinge et al., 2006), and intervals of decades also seem relevant to development of iatrogenic amyloid-β pathology (Jaunmuktane et al., 2015). 

    In our view, we not only must remain open to, but should actively investigate, whether AD epidemiology is similar, with rare iatrogenically acquired forms in addition to the large majority of sporadic and early onset inherited forms. As concluded at the workshop, we should develop improved methods to remove proteopathic seeds from surgical instruments on a precautionary basis (perhaps using a type of simple enzymatic prewash, as was successfully developed for prions), given that a full understanding of the scale of the risks will take years to unravel, along with consideration of new measures to ensure laboratory safety.

    —Peter Rudge and Zane Jaunmuktane are co-authors of this comment.

    References:

    . Intra-cerebral haemorrhage but not neurodegenerative disease appears over-represented in deaths of Australian cadaveric pituitary hormone recipients. Journal of Clinical Neuroscience, November 2020

    . Kuru in the 21st century--an acquired human prion disease with very long incubation periods. Lancet. 2006 Jun 24;367(9528):2068-74. PubMed.

    . Evaluation of potential infectivity of Alzheimer and Parkinson disease proteins in recipients of cadaver-derived human growth hormone. JAMA Neurol. 2013 Apr;70(4):462-8. PubMed.

    . Evidence for human transmission of amyloid-β pathology and cerebral amyloid angiopathy. Nature. 2015 Sep 10;525(7568):247-50. PubMed.

    . Transmission of amyloid-β protein pathology from cadaveric pituitary growth hormone. Nature. 2018 Dec;564(7736):415-419. Epub 2018 Dec 13 PubMed.

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References

News Citations

  1. Alzheimer’s Transmission Between People? Amyloid Plaques in Hormone Recipients Hint at Prion-like Spread
  2. Confirmed: Human Pituitary Extract Linked to Amyloidosis Contains Aβ Seeds
  3. News Brief: More Evidence for Aβ Spread Between People
  4. First In Vivo Look at Amyloidosis Sparked by Dural Grafts
  5. Can Aβ Seeds Be Transferred During Neurosurgery?
  6. Methods to Detect Amyloid Seeds Improve, Extend to Blood and Parkinson’s
  7. Bad Seeds—Potent Aβ Peptides Instigate Plaques, Won’t Be Fixed

Paper Citations

  1. . Global neurosurgery: the current capacity and deficit in the provision of essential neurosurgical care. Executive Summary of the Global Neurosurgery Initiative at the Program in Global Surgery and Social Change. J Neurosurg. 2018 Apr 1;:1-10. PubMed.
  2. . Fatal Aβ cerebral amyloid angiopathy 4 decades after a dural graft at the age of 2 years. Acta Neuropathol. 2018 May;135(5):801-803. Epub 2018 Mar 5 PubMed.
  3. . Cerebral hemorrhagic stroke associated with cerebral amyloid angiopathy in young adults about 3 decades after neurosurgeries in their infancy. J Neurol Sci. 2019 Apr 15;399:3-5. Epub 2019 Feb 1 PubMed.
  4. . Iatrogenic early onset cerebral amyloid angiopathy 30 years after cerebral trauma with neurosurgery: vascular amyloid deposits are made up of both Aβ40 and Aβ42. Acta Neuropathol Commun. 2019 May 2;7(1):70. PubMed.
  5. . Prion-Like Seeding of Misfolded α-Synuclein in the Brains of Dementia with Lewy Body Patients in RT-QUIC. Mol Neurobiol. 2017 May 26; PubMed.
  6. . Rapid and ultra-sensitive quantitation of disease-associated α-synuclein seeds in brain and cerebrospinal fluid by αSyn RT-QuIC. Acta Neuropathol Commun. 2018 Feb 9;6(1):7. PubMed.
  7. . A standardized comparison of commercially available prion decontamination reagents using the Standard Steel-Binding Assay. J Gen Virol. 2011 Mar;92(Pt 3):718-26. Epub 2010 Nov 17 PubMed.
  8. . Assessment of the efficacy of different procedures that remove and disassemble alpha-synuclein, tau and A-beta fibrils from laboratory material and surfaces. Sci Rep. 2018 Jul 17;8(1):10788. PubMed.
  9. . Transmission of Neurodegenerative Disorders Through Blood Transfusion: A Cohort Study. Ann Intern Med. 2016 Sep 6;165(5):316-24. Epub 2016 Jun 28 PubMed.

External Citations

  1. Dec 2018 Nature
  2. Feb 2019 Scientific American
  3. SCANDAT2 database

Further Reading

Primary Papers

  1. . Potential human transmission of amyloid β pathology: surveillance and risks. Lancet Neurol. 2020 Oct;19(10):872-878. Epub 2020 Sep 16 PubMed.