{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,5]],"date-time":"2026-08-05T11:34:52Z","timestamp":1785929692046,"version":"3.56.0"},"reference-count":45,"publisher":"MDPI AG","issue":"23","license":[{"start":{"date-parts":[[2024,12,4]],"date-time":"2024-12-04T00:00:00Z","timestamp":1733270400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"European Union","award":["964934"],"award-info":[{"award-number":["964934"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Amyloid-\u03b21\u201342 (A\u03b242) forms highly stable and insoluble fibrillar structures, representing the principal components of the amyloid plaques present in the brain of Alzheimer\u2019s disease (AD) patients. The involvement of A\u03b242 in AD-associated neurodegeneration has also been demonstrated, in particular for smaller and soluble aggregates (oligomers). Based on these findings and on genetic evidence, A\u03b242 aggregates are considered key players in the pathogenesis of AD and targets for novel therapies. Different approaches are currently used to detect the various aggregation states of A\u03b2 peptide, including spectrophotometric methods, imaging techniques, and immunoassays, but all of these have specific limitations. To overcome them, we have recently exploited the peculiar properties of surface plasmon resonance (SPR) to develop an immunoassay capable of selectively detecting monomers and oligomers, discriminating them also from bigger fibrils in a mixture of different aggregated species, without any manipulation of the solution. In the present study, we extended these previous studies, showing that the SPR-based immunoassay makes it possible to unveil the fibril fragmentation induced mechanically, a result difficult to be conveniently and reliably assessed with other approaches. Moreover, we show that SPR-recognized fibril fragments are more toxic than the larger fibrillar structures, suggesting the relevance of the proposed SPR-based immunoassay.<\/jats:p>","DOI":"10.3390\/ijms252313020","type":"journal-article","created":{"date-parts":[[2024,12,4]],"date-time":"2024-12-04T04:47:22Z","timestamp":1733287642000},"page":"13020","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["The Detection of Toxic Amyloid-\u03b2 Fibril Fragments Through a Surface Plasmon Resonance Immunoassay"],"prefix":"10.3390","volume":"25","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7201-6704","authenticated-orcid":false,"given":"Marten","family":"Beeg","sequence":"first","affiliation":[{"name":"Laboratory of Pharmacodynamics and Pharmacokinetics, Istituto di Ricerche Farmacologiche Mario Negri IRCCS Via Mario Negri 2, 20156 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Beatrice","family":"Rocutto","sequence":"additional","affiliation":[{"name":"Laboratory of Pharmacodynamics and Pharmacokinetics, Istituto di Ricerche Farmacologiche Mario Negri IRCCS Via Mario Negri 2, 20156 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Elisabetta","family":"Battocchio","sequence":"additional","affiliation":[{"name":"Laboratory of Pharmacodynamics and Pharmacokinetics, Istituto di Ricerche Farmacologiche Mario Negri IRCCS Via Mario Negri 2, 20156 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Letizia","family":"Dacomo","sequence":"additional","affiliation":[{"name":"Laboratory of Biology of Neurodegenerative Disorders, Istituto di Ricerche Farmacologiche Mario Negri IRCCS Via Mario Negri 2, 20156 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alessandro","family":"Corbelli","sequence":"additional","affiliation":[{"name":"Laboratory of Molecular Biology, Istituto di Ricerche Farmacologiche Mario Negri IRCCS Via Mario Negri 2, 20156 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0172-4030","authenticated-orcid":false,"given":"Fabio","family":"Fiordaliso","sequence":"additional","affiliation":[{"name":"Laboratory of Molecular Biology, Istituto di Ricerche Farmacologiche Mario Negri IRCCS Via Mario Negri 2, 20156 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Claudia","family":"Balducci","sequence":"additional","affiliation":[{"name":"Laboratory of Biology of Neurodegenerative Disorders, Istituto di Ricerche Farmacologiche Mario Negri IRCCS Via Mario Negri 2, 20156 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1014-6225","authenticated-orcid":false,"given":"Marco","family":"Gobbi","sequence":"additional","affiliation":[{"name":"Laboratory of Pharmacodynamics and Pharmacokinetics, Istituto di Ricerche Farmacologiche Mario Negri IRCCS Via Mario Negri 2, 20156 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,12,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"4760","DOI":"10.1038\/s41467-019-12683-8","article-title":"Cryo-EM Structure and Polymorphism of A\u03b2 Amyloid Fibrils Purified from Alzheimer\u2019s Brain Tissue","volume":"10","author":"Kollmer","year":"2019","journal-title":"Nat. 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