Blood amyloid and tau biomarkers as predictors of cerebrospinal fluid profiles

Blood biomarkers represent a major advance for improving the management, diagnosis, and monitoring of Alzheimer's disease (AD). However, their context of use in relation to routine cerebrospinal fluid (CSF) analysis for the quantification of amyloid peptides and tau proteins remains to be determined. We studied in two independent cohorts, the performance of blood biomarkers in detecting "nonpathological" (A−/T−/N−), amyloid (A+) or neurodegenerative (T+ /N+) CSF profiles. Plasma Aβ/Aβ ratio and phosphorylated tau (p-tau(181)) were independent and complementary predictors of the different CSF profile and in particular of the nonpathological (A−/T−/N−) profile with a sensitivity and specificity close to 85%. These performances and the corresponding biomarker thresholds were significantly different from those related to AD detection. The use of blood biomarkers to identify patients who may benefit from secondary CSF testing represents an attractive stratification strategy in the clinical management of patients visiting memory clinics. This could reduce the need for lumbar puncture and foreshadow the use of blood testing on larger populations. The online version contains supplementary material available at 10.1007/s00702-022-02474-9

The Sant Pau Initiative on Neurodegeneration (SPIN) cohort : A data set for biomarker discovery and validation in neurodegenerative disorders

Altres ajuts: The SPIN cohort has received funding from CIBERNED; Instituto de Salud Carlos III; jointly funded by Fondo Europeo de Desarrollo Regional (FEDER), Unión Europea, "Una manera de hacer Europa"; Generalitat de Catalunya; Fundació "La Marató TV3" Fundació Bancària Obra Social La Caixa; Fundación BBVA; Fundación Española para el Fomento de la Investigación de la Esclerosis Lateral Amiotrófica (FUNDELA); Global Brain Health Institute; Fundació Catalana Síndrome de Down; and Fundació Víctor Grífols i Lucas. These funding sources had no role in study design; in the collection, analysis, and interpretation of data; in the writing of the report; or in the decision to submit the article for publication.The SPIN (Sant Pau Initiative on Neurodegeneration) cohort is a multimodal biomarker platform designed for neurodegenerative disease research following an integrative approach. Participants of the SPIN cohort provide informed consent to donate blood and cerebrospinal fluid samples, receive detailed neurological and neuropsychological evaluations, and undergo a structural 3T brain MRI scan. A subset also undergoes other functional or imaging studies (video-polysomnogram, 18 F-fluorodeoxyglucose PET, amyloid PET, Tau PET). Participants are followed annually for a minimum of 4 years, with repeated cerebrospinal fluid collection and imaging studies performed every other year, and brain donation is encouraged. The integration of clinical, neuropsychological, genetic, biochemical, imaging, and neuropathological information and the harmonization of protocols under the same umbrella allows the discovery and validation of key biomarkers across several neurodegenerative diseases. We describe our particular 10-year experience and how different research projects were unified under an umbrella biomarker program, which might be of help to other research teams pursuing similar approaches

Etude des mécanismes moléculaires impliqués dans le recyclage du fer héminique au cours de l'erythrophagocytose

Au cours de l'érythrophagocytose (EP), le fer des érythrocytes sénescents est recyclé par les macrophages tissulaires de l'organisme, permettant ainsi de satisfaire les besoins érythropoïétiques journaliers. Les perturbations de ce processus se traduisent par des pathologies de surcharge et de carence en fer. Afin de préciser les mécanismes impliqués dans le recyclage du fer héminique, nous avons élaboré un modèle cellulaire murin d'EP, reproduisant le plus fidèlement possible les mécanismes physiologiques de clairance érythrocytaire. Nous avons alors étudié les modulations d'expression de gènes d'intérêt du métabolisme du fer au cours de l'EP et montré l'induction de HO-1 et de la ferroportine dans les premières heures de ce processus, suivie du maintien de HO-1 et de la répression de la ferroportine aux heures tardives. Nos études indiquent que Thème est catabolisée à l'extérieur du phagolysosorne contenant un érythrocyte, participant ainsi à la régulation transcriptionnelle de HO-1 et de la ferroportine au cours de l'EP. Par ailleurs, nous avons redéfinit et comparer la localisation, l'expression et la régulation de la ferroportine dans les entérocytes et les macrophages. Nos études montrent que la ferroportine macrophagique est présente au sein de vésicules intracellulaires, partiellement localisées à la membrane plasmique des cellules. Notre travail implique clairement l'hepcidine dans la régulation post-traductionnelle de la ferroportine macrophagique. Enfin, l'étude de diverses mutations du gène SLC40A1 (codant la ferroportine) dans un modèle de cellules épithéliales confirme leur effet sur la rétention intracellulaire et le disfonctionnement de l'exporteur.PARIS7-Bibliothèque centrale (751132105) / SudocPARIS-BIUP (751062107) / SudocSudocFranceF

Analytical challenges related to the use of biomarker ratios for the biological diagnosis of Alzheimer’s disease

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Biochemical markers of time since death in cerebrospinal fluid: A first step towards “Forensomics”

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Looking for new biomarkers of skin wound vitality with a cytokine-based multiplex assay: preliminary study.

International audienceDetermination of skin wound vitality is an important issue in forensic practice. No reliable biomarker currently exists. Quantification of inflammatory cytokines in injured skin with MSD® technology is an innovative and promising approach. This preliminary study aims to develop a protocol for the preparation and the analysis of skin samples. Samples from ante mortem wounds, post mortem wounds, and intact skin ("control samples") were taken from corpses at the autopsy. After an optimization of the pre-analytical protocol had been performed in terms of skin homogeneisation and proteic extraction, the concentration of TNF-α was measured in each sample with the MSD® approach. Then five other cytokines of interest (IL-1β, IL-6, IL-10, IL-12p70 and IFN-γ) were simultaneously quantified with a MSD® multiplex assay. The optimal pre-analytical conditions consist in a proteic extraction from a 6 mm diameter skin sample, in a PBS buffer with triton 0,05%. Our results show the linearity and the reproductibility of the TNF-α quantification with MSD®, and an inter- and intra-individual variability of the concentrations of proteins. The MSD® multiplex assay is likely to detect differential skin concentrations for each cytokine of interest. This preliminary study was used to develop and optimize the pre-analytical and analytical conditions of the MSD® method using injured and healthy skin samples, for the purpose of looking for and identifying the cytokine, or the set of cytokines, that may be biomarkers of skin wound vitality

Nano-flow vs standard-flow: Which is the more suitable LC/MS method for quantifying hepcidin-25 in human serum in routine clinical settings?

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NFL strongly correlates with TNF-R1 in the plasma of AD patients, but not with cognitive decline

Peripheral inflammation mechanisms involved in Alzheimer's disease (AD) have yet to be accurately characterized and the identification of blood biomarker profiles could help predict cognitive decline and optimize patient care. Blood biomarkers described to date have failed to provide a consensus signature, which is mainly due to the heterogeneity of the methods used or the cohort. The present work aims to describe the potential informativity of peripheral inflammation in AD, focusing in particular on the potential association between the level of plasma neurofilament light (NFL), peripheral inflammation (by quantifying IL-1β, IL-6, TNFα, CCL5, TNF-R1, sIL-6R, TIMP-1, IL-8 in blood) and cognitive decline (assessed by the MMSE and ADAScog scales) through a 2-year follow-up of 40 AD patients from the Cytocogma cohort (CHU Poitiers, Pr M. Paccalin). Our results show for the first time a strong correlation between plasma NFL and TNF-R1 at each time of follow-up (baseline, 12 and 24 months), thus opening an interesting perspective for the prognosis of AD patients

Clinical reporting following the quantification of cerebrospinal fluid biomarkers in Alzheimer's disease: an international overview

Introduction: the current practice of quantifying cerebrospinal fluid (CSF) biomarkers as an aid in the diagnosis of Alzheimer's disease (AD) varies from center to center. For a same biochemical profile, interpretation and reporting of results may differ, which can lead to misunderstandings and raises questions about the commutability of tests. Methods: We obtained a description of (pre-)analytical protocols and sample reports from 40 centers worldwide. A consensus approach allowed us to propose harmonized comments corresponding to the different CSF biomarker profiles observed in patients. Results: the (pre-)analytical procedures were similar between centers. There was considerable heterogeneity in cutoff definitions and report comments. We therefore identified and selected by consensus the most accurate and informative comments regarding the interpretation of CSF biomarkers in the context of AD diagnosis. Discussion: this is the first time that harmonized reports are proposed across worldwide specialized laboratories involved in the biochemical diagnosis of AD.This manuscript was facilitated by the Alzheimer's Association International Society to Advance Alzheimer's Research and Treatment (ISTAART), through the Biofluid Based Biomarkers Professional Interest Area (BBB-PIA). The views and opinions expressed in this publication represent those of the authors and do not necessarily reflect those of the BBB-PIA membership, ISTAART, or the Alzheimer's Association. The authors thank the French Society of Clinical Biology, the ISTAART BBB-PIA, and the Society for Neurochemistry and Clinical CSF analysis for their help in initiating this work. Constance Delaby received no support for the present manuscript. Charlotte Teunissen received the following grants during the last 36 months: Research of CET is supported by the European Commission (Marie Curie International Training Network, grant agreement No 860197 [MIRIADE], and JPND), Health Holland, the Dutch Research Council (ZonMw), Alzheimer Drug Discovery Foundation, The Selfridges Group Foundation, Alzheimer Netherlands, Alzheimer Association. CT and WF are recipients of ABOARD, which is a public-private partnership receiving funding from ZonMw (#73305095007) and Health∼Holland, Topsector Life Sciences & Health (PPP-allowance; #LSHM20106). More than 30 partners participate in ABOARD. ABOARD also receives funding from Edwin Bouw Fonds and Gieskes-Strijbisfonds. IV is appointed on a research grant by Alzheimer Nederland (NL-17004). She received no support for the present manuscript. Kaj Blennow is supported by the Swedish Alzheimer Foundation (#AF-742881) and Hjärnfonden, Sweden (#FO2017-0243). He received no support for the present manuscript. Daniel Alcolea received funding from Institute of Health Carlos III (ISCIII), Spain PI18/00435 and INT19/00016, and by the Department of Health Generalitat de Catalunya PERIS program SLT006/17/125. He received no support for the present manuscript. Ivan Arisi was partly supported by: Fondo Ordinario Enti (FOE D.M 865/2019) funds in the framework of a collaboration agreement between the Italian National Research Council and EBRI (2019-2021); POR (Operative Program Lazio Region, Italy) FESR (European Program Regional Development) 2014-2020, Public Notice “LIFE 2020” MODIAG Project. Elodie Bouaziz-Amar received no support for the present manuscript. Anne Beaume received no support for the present manuscript. Aurélie Bedel received no support for the present manuscript. Giovanni Bellomo is supported by University of Perugia, CIRMMP, IRST Istituto Romagnolo per lo Studio e la Cura dei Tumori, Innuvatech srl. He received no support for the present manuscript. Edith Bigot-Corbel received no support for the present manuscript. Maria Bjerke received no support for the present manuscript. Marie-Céline Blanc-Quintin received no support for the present manuscript. Mercè Boada received support from LA CAIXA, IMI, ISCIII H2020 the European Union/EFPIA Innovative Medicines Initiative Joint Undertaking MOPEAD project (Grants No. 115985) and is also supported by national grant, PI17/01474 from Acción Estratégica en Salud, integrated into the Spanish National Plan of R+D+I and founded by ISCIII (Instituto de Salud Carlos III)-Subdirección General de Evaluación and the Fondo Europeo de Desarrollo Regional (FEDER- “Una manera de Hacer Europa”). She received no support for the present manuscript. Olivier Bousigues is supported by A2MCL Alsace Alzheimer. He received no support for the present manuscript. Miles D. Chapman received no support for the present manuscript. Mari L. DeMarco is supported by the Michael Smith Foundation for Health Research, Brain Canada (Canada Brain Research Fund), Health Canada, Women's Brain Health Initiative, Alzheimer Society of Canada, St. Paul's Foundation, Djavad Mowafaghian Centre for Brain Health at the University of British Columbia and the Canadian Consortium for Neurodegeneration and Aging; with all funds provided to the University of British Columbia. Mara D'Onofrio was partly supported by Fondo Ordinario Enti (FOE D.M 865/2019) funds in the framework of a collaboration agreement between the Italian National Research Council POR (Operative Program Lazio Region, Italy) FESR (European Program Regional Development) 2014-2020, Public Notice “LIFE 2020″, MODIAG Project. She received no support for the present manuscript. Julien Dumurgier received no support for the present manuscript. Diane Dufour received no support for the present manuscript. Sebastiaan Engelborghs is supported for various projects: Research Project GSKE/FMRE, Research Project FWO Vlaanderen, PhD fellowship FWO Vlaanderen (n = 3), VLAIO PhD fellowship. He received no support for the present manuscript. Hermann Esselmann received no support for the present manuscript. Anne Fogli received no support for the present manuscript. Audrey Gabelle received no support for the present manuscript. Elisabetta Galloni received no support for the present manuscript. Clémentine Gondolf received no support for the present manuscript. Frédérique Grandhomme received no support for the present manuscript. Oriol Grau-Rivera receives grants from the Spanish Ministry of Science, Innovation and Universities (FJCI-2017-33437), and from the Alzheimer's Association Research Fellowship Program (2019-AARF-644568). He received no support for the present manuscript. Melanie Hart receives UCLH Biomedical Research Centre support from NIHR (Neurosciences). She received no support for the present manuscript. Takeshi Ikeuchi received the following grants to his institution AMED: 21dk0207049, 21dk0207045, 21ek0109545, 20ek0109350, 20ek0109392. He received no support for the present manuscript. Andreas Jeromin received no support for the present manuscript. Kensaku Kasuga received no support for the present manuscript. Ashvini Keshavan is supported by the Weston Brain Institute/Selfridges Foundation grant UB170045. She received no support for the present manuscript. Michael Khalil received unrestricted research grants from Biogen and Novartis. He received no support for the present manuscript. Peter Körtvelyessy received no support for the present manuscript. Agnieszka Kulczynska-Przybik received no support for the present manuscript. Jean-Louis Laplanche received no support for the present manuscript. Qiao-Xin Li received no support for the present manuscript. Alberto Lleó is supported by grants from Generalitat de Catalunya (PERIS SLT002/16/00408), Instituto de Salud Carlos III (PI17/01896), Instituto de Salud Carlos III CIBERNED. He received no support for the present manuscript. Catherine Malaplate received no support for the present manuscript. Marta Marquié is supported by the Instituto de Salud Carlos III (ISCIII) Acción Estratégica en Salud, integrated in the Spanish National RCDCI Plan and financed by ISCIII-Subdirección General de Evaluación and the Fondo Europeo de Desarrollo Regional (FEDER-Una manera de hacer Europa) grant PI19/00335. She received no support for the present manuscript. Colin M. Masters received no support for the present manuscript. Barbara Mroczko received a grant from The Binding Site Group and Biokom Diagnostyka. She received no support for the present manuscript. Léonor Nogueira received no support for the present manuscript. Adelina Orellana received no support for the present manuscript. Markus Otto is supported by BMBF, Thierry Latran foundation, EU, DFG. He received no support for the present manuscript. Jean-Baptiste Oudart is supported by Astrazeneca grant for a research program on EGFR targeted therapy resistance in NSCLC. He received no support for the present manuscript. Claire Paquet received no support for the present manuscript. Federico Paolini received no support for the present manuscript. Lucilla Parnetti received no support for the present manuscript. Armand Perret-Liaudet received no support for the present manuscript. Katell Peoc'h is supported by contract with Siemens Healthineers. She received no support for the present manuscript. Koen Poesen received no support for the present manuscript. Albert Puig-Pijoan received no support for the present manuscript. Isabelle Quadrio received no support for the present manuscript. Murielle Quillard-Muraine received no support for the present manuscript. Benoît Rucheton received no support for the present manuscript. Susanne Schraen received no support for the present manuscript. Jonathan M. Schott is supported by the Medical Research Council, Alzheimer's Research UK, Weston Brain Institute, British Heart Foundation, Alzheimer's Association. He received no support for the present manuscript. Leslie M. Shaw is supported by NIA for ADNI Biomarker Core, UPENN ADRC Biomarker Corr, MJ Fox PPMI for CSF Biomarker measurements, Roche for IIS study of AD biomarkers. He received no support for the present manuscript. Marc Suárez-Calvet receives funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation program (Grant agreement No. 948677). He also receives funding from the Instituto de Salud Carlos III (PI19/00155) and from the Spanish Ministry of Science, Innovation and Universities (Juan de la Cierva Programme grant IJC2018-037478-I). He received no support for the present manuscript. Magda Tsolaki received no support for the present manuscript. Hayrettin Tumani is supported by Alexion, Bayer, Biogen, Celgene, Genzyme-Sanofi, Merck, Novartis, Roche, Teva. He received no support for the present manuscript. Chinedu T Udeh-Momoh is supported by Alzheimer research UK (Project Grant). He received no support for the present manuscript. Lucie Vaudran received no support for the present manuscript. Marcel M. Verbeek is supported by the BIONIC project (no. 733050822, which has been made possible by ZonMw within the framework of “Memorabel,” the research and innovation program for dementia, as part of the Dutch national “Deltaplan for Dementia”: zonmw.nl/dementiaresearch), and the CAFÉ project (the National Institutes of Health, USA, grant number 5R01NS104147-02). The BIONIC project is a consortium of Radboudumc, LUMC, ADX Neurosciences, and University of Rhode Island University. MM Verbeek is also supported by a grant from the Selfridges Group Foundation. He received no support for the present manuscript. Federico Verde received no support for the present manuscript. Lisa Vermunt is supported by Alzheimer Nederland. She received no support for the present manuscript. Jonathan Volgesgang is supported by Clinician Scientist Research Fellowship, German Research Foundation (Deutsche Forschungsgesellschaft, project number: 413501650; 09/01/2019-02/28/2021); Eric Dorris Memorial Fellowship (McLean Hospital; 07/01/2020-06/30/2021). He received no support for the present manuscript. Jens Wiltfang is supported by Federal Ministry of Education and Research (BMBF) State of Lower Saxony; He received no support for the present manuscript. Henrik Zetterberg is a Wallenberg Scholar supported by grants from the Swedish Research Council (#2018-02532), the European Research Council (#681712), Swedish State Support for Clinical Research (#ALFGBG-720931), the Alzheimer Drug Discovery Foundation (ADDF), USA (#201809-2016862), the AD Strategic Fund and the Alzheimer's Association (#ADSF-21-831376-C, #ADSF-21-831381-C and #ADSF-21-831377-C), the Olav Thon Foundation, the Erling-Persson Family Foundation, Stiftelsen för Gamla Tjänarinnor, Hjärnfonden, Sweden (#FO2019-0228), the European Union's Horizon 2020 research and innovation program under the Marie Skłodowska-Curie grant agreement No 860197 (MIRIADE), and the UK Dementia Research Institute at UCL. He received no support for the present manuscript. Sylvain Lehmann received no support for the present manuscript

Relevance of Aβ42/40 Ratio for Detection of Alzheimer Disease Pathology in Clinical Routine: The PLMR Scale

Background: Cerebrospinal fluid (CSF) biomarkers (Aβ peptides and tau proteins) improved the diagnosis of Alzheimer’s disease (AD) in research and clinical settings. We previously described the PLM-scale (Paris-Lille-Montpellier study), which combines Aβ42, tau, and phosphorylated ptau(181) biomarkers in an easy to use and clinically relevant way. The purpose of this work is to evaluate an optimized PLMR-scale (PLM ratio scale) that now includes the Aβ42/Aβ40 ratio to detect AD versus non-AD (NAD) participants in clinical routine of memory centers.Methods: Both scales were compared using 904 participants with cognitive impairment recruited from two independent cohorts (Mtp-1 and Mtp-2). The CSF Aβ42/Aβ40 ratio was measured systematically in Mtp-1, and only on biologically discordant cases in Mtp-2. Two different ELISA kit providers were also employed. The distribution of AD and NAD patients and the discrepancies of biomarker profiles were computed. Receiver Operating Characteristic curves were used to represent clinical sensitivity and specificity for AD detection. The classification of patients with the net reclassification index (NRI) was also evaluated.Results: Nine hundred and four participants (342 AD and 562 NAD) were studied; 400 in Mtp-1 and 504 in Mtp-2. For AD patients, the mean CSF Aβ42 and CSF Aβ42/40 ratio was 553 ± 216 pg/mL and 0.069 ± 0.022 pg/mL in Mtp-1 and 702 ± 335 pg/mL and 0.045 ± 0.020 pg/mL in Mtp-2. The distribution of AD and NAD differed between the PLM and the PLMR scales (p < 0.0001). The percentage AD well-classified (class 3) increased with PLMR from 38 to 83% in Mpt-1 and from 33 to 53% in Mpt-2. A sharp reduction of the discordant profiles going from 34 to 16.3% and from 37.5 to 19.8%, for Mtp-1 and Mtp-2 respectively, was also observed. The AUC of the PLMR scale was 0.94 in Mtp-1 and 0.87 in Mtp-2. In both cohorts, the PLMR outperformed CSF Aβ42 or Aβ42/40 ratio. The diagnostic performance was improved with the PLMR with an NRI equal to 44.3% in Mtp-1 and 28.8% in Mtp-2.Conclusion: The integration of the Aβ42/Aβ40 ratio in the PLMR scale resulted in an easy-to-use tool which reduced the discrepancies in biologically doubtful cases and increased the confidence in the diagnosis in memory center