Plasma diagnosis marker for Alzheimer's disease based on plasma pTau217 and application

Abstract

The invention discloses an Alzheimer's disease plasma diagnosis marker based on plasma pTau217 and application of the Alzheimer's disease plasma diagnosis marker. The plasma biomarker provided by the invention is pTau217, pTau217 / A beta 1-40 or pTau217 / A beta 1-42, and the detection of the plasma biomarker not only belongs to a reliable, simple and convenient non-invasive means, but also can efficiently evaluate the disease risk of the Alzheimer's disease. The method can replace the traditional Alzheimer disease detection method, such as cerebrospinal fluid amyloid protein detection and PET imaging, and is easy to clinically and widely apply. The method has an important application value.

Description

Technical Field

[0001] The present invention belongs to the field of medical care informatics, and specifically relates to an Alzheimer's disease plasma diagnostic marker based on plasma pTau217 and an application thereof. Background Art

[0002] Alzheimer's disease (AD) is the most common type of dementia and an important cause of disability in the elderly population.

[0003] There is currently no effective treatment to cure AD, so early identification and timely intervention of AD are extremely important. The pathological changes of AD include brain Aβ amyloid protein deposition, Tau protein neuronal entanglement, etc. These pathological changes can appear up to 20 years earlier than clinical symptoms, so AD pathological diagnosis technology can provide the possibility for timely identification of individuals at high risk of AD. Based on this, the internationally renowned AD research organization National Institute of Aging (NIA) and the Alzheimer's Association (AA) proposed the concept of the Alzheimer's Disease Continuum in 2018 (see Figure 1 ) and the matching AD biological diagnostic framework. The AD continuous disease spectrum includes three stages: preclinical, mild cognitive impairment (MCI), and dementia. There are no symptoms in the preclinical stage, but pathological changes can be detected; patients in the MCI stage will have mild memory loss, but their daily living ability is normal, and pathological markers will be obviously abnormal; these two stages are the golden period for AD spectrum intervention. Identifying AD individuals in the preclinical and MCI stages through pathological diagnostic technology and based on targeted treatment will greatly reduce the risk of AD dementia.

[0004] There are two main traditional pathological diagnostic technologies for AD, namely cerebrospinal fluid biomarker detection and positron emission tomography (PET) technology. These two technologies can efficiently and sensitively identify early brain AD pathology, but problems such as invasiveness, high cost and radioactivity limit their promotion and application. With the advancement of medical testing technology, specific AD plasma biomarkers can achieve AD pathological diagnosis more easily and quickly. Because of their advantages of being non-invasive, economical and highly accurate, they have been included in the consensus recommendations of domestic and international AD pathological diagnosis experts. At present, relevant research on the detection of new plasma biomarkers for AD diagnosis has been carried out in various parts of the world, but there are great differences in the cut-off values ​​reported between different analysis platforms and laboratories. Therefore, the development of plasma biomarkers for the diagnosis of Alzheimer's disease has important application value. Summary of the invention

[0005] The purpose of the present invention is to assess the risk of Alzheimer's disease or evaluate the possibility of pathological changes of Alzheimer's disease occurring in the brain.

[0006] The present invention first protects a plasma biomarker, which includes pTau217.

[0007] The plasma biomarker may specifically be pTau217.

[0008] Any of the above-mentioned plasma biomarkers may also include Aβ1-40 or Aβ1-42. The plasma biomarker may specifically consist of pTau217 and Aβ1-40. The plasma biomarker may specifically consist of pTau217 and Aβ1-42.

[0009] Preferably, the plasma biomarker may be pTau217 / Aβ1-40; and pTau217 / Aβ1-40 is the concentration ratio of pTau217 and Aβ1-40.

[0010] Preferably, the plasma biomarker may be pTau217 / Aβ1-42; and pTau217 / Aβ1-42 is the concentration ratio of pTau217 and Aβ1-42.

[0011] The detection object of any of the above-mentioned plasma biomarkers can be plasma.

[0012] The use of any of the above-mentioned plasma biomarkers in the preparation of a product for assessing the risk of Alzheimer's disease or a product for evaluating the possibility of Alzheimer's disease pathological changes in the brain also falls within the scope of protection of the present invention.

[0013] The use of substance A, substance B or substance C in the preparation of a product for assessing the risk of Alzheimer's disease or a product for evaluating the possibility of pathological changes of Alzheimer's disease in the brain also falls within the scope of protection of the present invention;

[0014] The substance A may be a substance used to detect the concentration of pTau217 in plasma;

[0015] The substance B may be a substance used to detect the concentration of pTau217 and Aβ1-40 in plasma;

[0016] The substance C may be a substance for detecting the concentration of pTau217 and Aβ1-42 in plasma.

[0017] The present invention also protects a data processing device for evaluating the risk of a subject suffering from Alzheimer's disease or evaluating the possibility of pathological changes of Alzheimer's disease occurring in the brain of the subject, which may be data processing device 1, data processing device 2 or data processing device 3.

[0018] The data processing device 1 may include the following modules:

[0019] (1) a data receiving module; the data receiving module is configured to receive the content of pTau217 in the plasma of the subject;

[0020] (2) a data processing module; the data processing module is configured to receive the content of pTau217 in the plasma of the subject from the data receiving module;

[0021] (3) a data storage module; the data storage module is configured to store the judgment threshold;

[0022] (4) a data comparison module; the data comparison module is configured to receive pTau217 sent by the data processing module, and call the judgment threshold from the data storage module for comparison with pTau217;

[0023] (5) a judgment module; the judgment module is configured to receive the comparison result sent by the data comparison module, judge the comparison result according to a predetermined judgment condition, and output the judgment result;

[0024] The predetermined judgment condition is: if the pTau217 value is greater than the judgment threshold, the subject has a high risk of Alzheimer's disease or a high possibility of pathological changes of Alzheimer's disease in the brain; otherwise, the subject has a low risk of Alzheimer's disease or a low possibility of pathological changes of Alzheimer's disease in the brain.

[0025] The data processing device 2 may include the following modules:

[0026] (1) a data receiving module; the data receiving module is configured to receive the content of pTau217 and the content of Aβ1-40 in the plasma of the subject;

[0027] (2) a data processing module; the data processing module is configured to receive the pTau217 content and the Aβ1-40 content in the plasma of the subject from the data receiving module, and calculate the ratio of the pTau217 content to the Aβ1-40 content, which is recorded as pTau217 / Aβ1-40;

[0028] (3) a data storage module; the data storage module is configured to store the judgment threshold;

[0029] (4) a data comparison module; the data comparison module is configured to receive the pTau217 / Aβ1-40 sent by the data processing module, and call the judgment threshold from the data storage module for comparison with the pTau217 / Aβ1-40;

[0030] (5) a judgment module; the judgment module is configured to receive the comparison result sent by the data comparison module, judge the comparison result according to a predetermined judgment condition, and output the judgment result;

[0031] The predetermined judgment condition is: if the pTau217 / Aβ1-40 value is greater than the judgment threshold, the subject has a high risk of Alzheimer's disease or a high possibility of pathological changes of Alzheimer's disease in the brain; otherwise, the subject has a low risk of Alzheimer's disease or a low possibility of pathological changes of Alzheimer's disease in the brain.

[0032] The data processing device 3 may include the following modules:

[0033] (1) a data receiving module; the data receiving module is configured to receive the content of pTau217 and the content of Aβ1-42 in the plasma of the subject;

[0034] (2) a data processing module; the data processing module is configured to receive the pTau217 content and the Aβ1-42 content in the plasma of the subject from the data receiving module, and calculate the ratio of the pTau217 content to the Aβ1-42 content, which is recorded as pTau217 / Aβ1-42;

[0035] (3) a data storage module; the data storage module is configured to store the judgment threshold;

[0036] (4) a data comparison module; the data comparison module is configured to receive the pTau217 / Aβ1-42 sent by the data processing module, and call the judgment threshold from the data storage module for comparison with the pTau217 / Aβ1-42;

[0037] (5) a judgment module; the judgment module is configured to receive the comparison result sent by the data comparison module, judge the comparison result according to a predetermined judgment condition, and output the judgment result;

[0038] The predetermined judgment condition is: if the pTau217 / Aβ1-42 value is greater than the judgment threshold, the subject has a high risk of Alzheimer's disease or a high possibility of pathological changes of Alzheimer's disease in the brain; otherwise, the subject has a low risk of Alzheimer's disease or a low possibility of pathological changes of Alzheimer's disease in the brain.

[0039] In the data processing device 1, the judgment threshold stored in the data storage module may be 0.242 pg / ml.

[0040] In the data processing device 2, the judgment threshold stored in the data storage module may be 0.001.

[0041] In the data processing device 3, the judgment threshold stored in the data storage module may be 0.012.

[0042] In the data processing device 1, the content of pTau217 in the plasma of the subject to be tested received by the data receiving module is obtained according to a method comprising the following steps: collecting peripheral blood of the subject to be tested, separating the plasma, and then detecting the content of pTau217 in the plasma.

[0043] In the data processing device 2, the content of pTau217 and the content of Aβ1-40 in the plasma of the subject received by the data receiving module are obtained according to a method including the following steps: collecting peripheral blood of the subject, separating the plasma, and then detecting the content of pTau217 and the content of Aβ1-40 in the plasma.

[0044] In the data processing device 3, the content of pTau217 and the content of Aβ1-42 in the plasma of the subject received by the data receiving module are obtained according to a method including the following steps: collecting peripheral blood of the subject, separating the plasma, and then detecting the content of pTau217 and the content of Aβ1-42 in the plasma.

[0045] The data processing device may further include a control module or a controller; the control module or the controller is used to control each module.

[0046] The data processing device may specifically be composed of any of the above-mentioned data receiving modules, any of the above-mentioned data processing modules, any of the above-mentioned data storage modules, any of the above-mentioned data comparison modules and any of the above-mentioned judgment modules.

[0047] Any of the above-mentioned data processing devices may also include a control module or a controller; the control module or the controller is used to control each module.

[0048] The data processing device may specifically be composed of any of the above-mentioned data receiving modules, any of the above-mentioned data processing modules, any of the above-mentioned data storage modules, any of the above-mentioned data comparison modules, any of the above-mentioned judgment modules and a control module (or controller).

[0049] The present invention also protects a system for evaluating the risk of developing Alzheimer's disease or the possibility of Alzheimer's disease pathological changes occurring in the brain, which may include a control device 1, a control device 2 or a control device 3.

[0050] The control device 1 is configured or programmed to perform the following steps:

[0051] Receiving the content of pTau217 in the plasma of the subject to be tested;

[0052] Comparing the pTau217 content in the plasma of the subject to be tested with the judgment threshold value to obtain a comparison result;

[0053] Determine the comparison result according to a predetermined determination condition and output the determination result;

[0054] The predetermined judgment condition is: if the pTau217 value is greater than the judgment threshold, the subject has a high risk of Alzheimer's disease or a high possibility of pathological changes of Alzheimer's disease in the brain; otherwise, the subject has a low risk of Alzheimer's disease or a low possibility of pathological changes of Alzheimer's disease in the brain.

[0055] The system including the control device 1 also includes an input device and an output device; the input device is configured to input the content of pTau217 in the plasma of the subject to be tested; and the output device is configured to output the determination result.

[0056] The control device 2 is configured or programmed to perform the following steps:

[0057] Receiving the content of pTau217 and Aβ1-40 in the plasma of the subject to be tested;

[0058] According to the content of pTau217 and the content of Aβ1-40 in the plasma of the test subject, the ratio of the content of pTau217 to the content of Aβ1-40 is calculated, and recorded as pTau217 / Aβ1-40;

[0059] Comparing the pTau217 / Aβ1-40 in the plasma of the subject to be tested with the judgment threshold to obtain a comparison result;

[0060] Determine the comparison result according to a predetermined determination condition and output the determination result;

[0061] The predetermined judgment condition is: if the pTau217 / Aβ1-40 value is greater than the judgment threshold, the subject has a high risk of Alzheimer's disease or a high possibility of pathological changes of Alzheimer's disease in the brain; otherwise, the subject has a low risk of Alzheimer's disease or a low possibility of pathological changes of Alzheimer's disease in the brain.

[0062] The system including the control device 2 also includes an input device and an output device; the input device is configured to input the content of pTau217 and the content of Aβ1-40 in the plasma of the subject to be tested; and the output device is configured to output the determination result.

[0063] The control device 3 is configured or programmed to perform the following steps:

[0064] Receiving the content of pTau217 and Aβ1-42 in the plasma of the subject to be tested;

[0065] According to the content of pTau217 and the content of Aβ1-42 in the plasma of the test subject, the ratio of the content of pTau217 to the content of Aβ1-42 is calculated, and recorded as pTau217 / Aβ1-42;

[0066] Comparing the pTau217 / Aβ1-42 in the plasma of the subject to be tested with the judgment threshold to obtain a comparison result;

[0067] Determine the comparison result according to a predetermined determination condition and output the determination result;

[0068] The predetermined judgment condition is: if the pTau217 / Aβ1-42 value is greater than the judgment threshold, the subject has a high risk of Alzheimer's disease or a high possibility of pathological changes of Alzheimer's disease in the brain; otherwise, the subject has a low risk of Alzheimer's disease or a low possibility of pathological changes of Alzheimer's disease in the brain.

[0069] The system including the control device 3 also includes an input device and an output device; the input device is configured to input the content of pTau217 and the content of Aβ1-42 in the plasma of the subject to be tested; and the output device is configured to output the determination result.

[0070] The present invention also protects a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program for executing the following steps: the steps are step 1, step 2, or step 3.

[0071] The step 1 may be:

[0072] Receiving the content of pTau217 in the plasma of the subject to be tested;

[0073] Comparing the pTau217 content in the plasma of the subject to be tested with the judgment threshold value to obtain a comparison result;

[0074] Determine the comparison result according to a predetermined determination condition and output the determination result;

[0075] The predetermined judgment condition is: if the pTau217 value is greater than the judgment threshold, the subject has a high risk of suffering from Alzheimer's disease or a high possibility of Alzheimer's disease pathological changes in the brain; otherwise, the subject has a low risk of suffering from Alzheimer's disease or a low possibility of Alzheimer's disease pathological changes in the brain;

[0076] The system including the control device 1 also includes an input device and an output device; the input device is configured to input the content of pTau217 in the plasma of the subject to be tested; and the output device is configured to output the determination result.

[0077] The step 2 may be:

[0078] Receiving the content of pTau217 and Aβ1-40 in the plasma of the subject to be tested;

[0079] According to the content of pTau217 and the content of Aβ1-40 in the plasma of the test subject, the ratio of the content of pTau217 to the content of Aβ1-40 is calculated, and recorded as pTau217 / Aβ1-40;

[0080] Comparing the pTau217 / Aβ1-40 in the plasma of the subject to be tested with the judgment threshold to obtain a comparison result;

[0081] Determine the comparison result according to a predetermined determination condition and output the determination result;

[0082] The predetermined judgment condition is: if the pTau217 / Aβ1-40 value is greater than the judgment threshold, the subject has a high risk of Alzheimer's disease or a high possibility of pathological changes of Alzheimer's disease in the brain; otherwise, the subject has a low risk of Alzheimer's disease or a low possibility of pathological changes of Alzheimer's disease in the brain.

[0083] The step 3 may be:

[0084] Receiving the content of pTau217 and Aβ1-42 in the plasma of the subject to be tested;

[0085] According to the content of pTau217 and the content of Aβ1-42 in the plasma of the test subject, the ratio of the content of pTau217 to the content of Aβ1-42 is calculated, and recorded as pTau217 / Aβ1-42;

[0086] Comparing the pTau217 / Aβ1-42 in the plasma of the subject to be tested with the judgment threshold to obtain a comparison result;

[0087] Determine the comparison result according to a predetermined determination condition and output the determination result;

[0088] The predetermined judgment condition is: if the pTau217 / Aβ1-42 value is greater than the judgment threshold, the subject has a high risk of Alzheimer's disease or a high possibility of pathological changes of Alzheimer's disease in the brain; otherwise, the subject has a low risk of Alzheimer's disease or a low possibility of pathological changes of Alzheimer's disease in the brain.

[0089] Traditional Alzheimer's continuous disease spectrum pathological diagnosis technologies such as cerebrospinal fluid amyloid protein detection or electron emission imaging (PET) technology have many limitations, such as high prices or trauma to human tissue. The present invention provides a reliable, simple and non-invasive means for diagnosing the Alzheimer's continuous disease spectrum by detecting the content of pTau217 in plasma and setting an accurate diagnostic threshold based on Chinese elderly samples, which is expected to replace traditional detection methods. At the same time, the three plasma biomarkers provided by the present invention - pTau217, pTau217 / Aβ1-40 and pTau217 / Aβ1-42, can all efficiently assess the risk of Alzheimer's disease, provide an effective, simple and non-invasive means for diagnosing AD, and are of great significance for the community and grassroots to carry out simple AD early screening; using the technology of the present invention to detect the cause of the patient and avoid misdiagnosis, it will help to conduct blood tests in grassroots institutions such as communities and identify AD high-risk groups early. The present invention can replace traditional Alzheimer's disease detection methods, such as cerebrospinal fluid amyloid protein detection and PET imaging, and is easy to be widely used in clinical practice. The present invention has important application value. BRIEF DESCRIPTION OF THE DRAWINGS

[0090] Figure 1 This is the cut-off value discriminant diagram of pTau217 in plasma of the SCABI cohort.

[0091] Figure 2 Figure 2 is the ROC curve of pTau217 in plasma of the SCABI cohort.

[0092] Figure 3 This is the cut-off value discrimination diagram of pTau217 / Aβ1-40 in plasma of the SCABI cohort.

[0093] Figure 4 This is the ROC curve of pTau217 / Aβ1-40 in plasma of the SCABI cohort.

[0094] Figure 5 This is the cut-off value discrimination diagram of pTau217 / Aβ1-42 in plasma of the SCABI cohort.

[0095] Figure 6 This is the ROC curve of pTau217 / Aβ1-42 in plasma of the SCABI cohort. DETAILED DESCRIPTION

[0096] The present invention is further described in detail below in conjunction with specific embodiments, and the examples provided are only for illustrating the present invention, rather than for limiting the scope of the present invention. The examples provided below can be used as a guide for further improvements by those of ordinary skill in the art, and do not constitute a limitation of the present invention in any way.

[0097] The experimental methods in the following examples, unless otherwise specified, are all conventional methods, and are performed according to the techniques or conditions described in the literature in the field or according to the product instructions. The materials, reagents, etc. used in the following examples, unless otherwise specified, can all be obtained from commercial channels.

[0098] The quantitative tests in the following examples were all repeated three times, and the results were averaged.

[0099] Cut-off value refers to the critical value in medical testing, which is used to determine whether the test result is higher or lower than the clinical or analytical decision point. If the positive and negative values ​​are determined when a marker is tested, the critical value with the highest sensitivity and specificity is usually used as the decision value, and this value is called the Cut-off value. The Cut-off value is mainly a critical point set based on statistical analysis.

[0100] The following examples were approved by the Ethics Committee of the Affiliated Brain Hospital of Guangzhou Medical University (ID: AF / SC-08 / 02.3) and complied with the 1964 Declaration of Helsinki and its subsequent amendments or similar ethical standards.

[0101] Example 1. Application of pTau217, the ratio of pTau217 to Aβ1-40 (hereinafter referred to as pTau217 / Aβ1-40), and the ratio of pTau217 to Aβ1-42 (hereinafter referred to as pTau217 / Aβ1-42) in plasma in the diagnosis of Alzheimer's disease

[0102] This example aims to explore the feasibility of diagnosing Alzheimer's disease using pTau217, pTau217 / Aβ1-40 and pTau217 / Aβ1-42 in plasma and analyze its clinical value.

[0103] In the following embodiments, pTau217 may also be written as ptau217 or Ptau217.

[0104] 1. Experimental Design

[0105] The purpose of this example is to determine the optimal cut-off values ​​of pTau217, pTau217 / Aβ1-40 and pTau217 / Aβ1-42 in plasma for diagnosing Alzheimer's disease using the automatic immunoassay analyzer Lumipulse G1200, and to evaluate the consistency of pTau217, pTau217 / Aβ1-40 and pTau217 / Aβ1-42 in plasma with the amyloid protein PET results.

[0106] 2. Experimental Methods

[0107] 1. Source of subjects and their inclusion and exclusion criteria

[0108] All subjects were from the Southern China Aging Brain Cohort (SCABI cohort). From March 2021 to June 2024, 182 SCABI cohort subjects underwent blood sample and amyloid PET image collection. Among them, the inclusion and exclusion criteria are as follows:

[0109] (1) Inclusion criteria

[0110] ①Age ≥50 years old;

[0111] ② Normal cognition, or MCI (according to Peterson criteria: Petersen RC. Mild cognitive impairment as a diagnostic entity. J Intern Med 2004; 256: 183–94. https: / / doi.org / 10.1111 / j.1365-2796.2004.01388.x), or dementia (according to DSM-IV criteria for any dementia: Association AP. Diagnostic and Statistical Manual of Mental Disorders. Text Revision 2000.).

[0112] ③Dividing the amyloid negative group and positive group according to the visual interpretation of PET amyloid: Image interpretation was completed by imaging experts who were unaware of the subject's diagnosis and biomarker levels, and all PET scan images were visually evaluated according to FDA recommendations: When one or more areas showed an increase in cortical gray matter signal, resulting in a decrease or disappearance of the contrast between gray matter and white matter, it was classified as "positive". When the contrast between gray matter and white matter was clear, it was classified as "negative" (Approval for Amyvid (Florbetapir F 18

[0113] Injection)2012.https: / / www.accessdata.fda.gov / drugsatfda_docs / nda / 2012 / 202008Orig1s000Approv.pdf(accessed October 18,2024).)

[0114] ④The subjects and their families agreed to participate in this study and signed the informed consent form.

[0115] (2) Exclusion criteria

[0116] ① Malignant tumors and severe cerebrovascular diseases (accompanied by neurological deficits, cerebral infarction and cerebral hemorrhage)

[0117] ②Severe neurological diseases (such as metabolic encephalopathy, encephalitis, multiple sclerosis, epilepsy, traumatic brain injury, normal pressure hydrocephalus, etc.)

[0118] ③Severe mental illness (schizophrenia, bipolar disorder, schizoaffective disorder, paranoid psychosis, intellectual disability, etc.)

[0119] ④ Other physical diseases that cause cognitive impairment (liver dysfunction, renal insufficiency, thyroid dysfunction, severe anemia, folic acid or vitamin B12 deficiency, syphilis, HIV infection, alcohol and drug abuse, etc.)

[0120] 2. Data Collection

[0121] (1) Clinical data collection

[0122] The age, gender, height, weight, waist circumference, medical history (including hypertension, diabetes, hypercholesterolemia, coronary heart disease, etc.), personal history (such as smoking, drinking, etc.), family history, medication history, education level, overall cognitive function scale score (MMSE), dementia grade scale score, etc. of each subject were recorded.

[0123] (2) Obtaining and testing plasma samples

[0124] ① Use 5 ml polypropylene tubes to collect blood samples. The blood samples should be collected within three months after the amyloid protein PET image is collected.

[0125] ② Take the collected blood sample, centrifuge it at 4°C and 2000rpm for 10min, collect 0.5ml of supernatant and store it at -80°C; the supernatant is the plasma sample (the plasma sample must be separated within 4h after the blood sample is collected, for specific reference: Giulia, Musso, Chiara, Cosma, Martina, Zaninotto et al. Pre-analytical variability of the Lumipulse immunoassay for plasma biomarkers of Alzheimer's disease. [J]. Clin Chem Lab Med, 2022, 61: 0.).

[0126] ③ The automatic immunoassay analyzer Lumipulse G1200 (Fujirebio) was used to detect the levels of biomarkers in 182 plasma samples, including Aβ1-42, Aβ1-40 and pTau217.

[0127] The measurement process uses special kits, including Lumipulse Gβ-Amyloid 1-40Plasma, Lumipulse G pTau217 and Lumipulse Gβ-Amyloid 1-42Plasma kits (Francisco, Martínez-Dubarbie, Armando, Guerra-Ruiz, Sara, López-García et al. Accuracy of plasma Aβ40, Aβ42, and p-tau181 to detect CSF Alzheimer's pathological changes incognitively unimpaired subjects using the Lumipulse automated platform. [J]. Alzheimers Res Ther, 2023, 15: 0.).

[0128] (3) Amyloid PET Image Acquisition

[0129] 18F-AV45 was prepared by the PET Center of Guangdong Provincial Hospital of Traditional Chinese Medicine, University Town Hospital. The preparation method was referred to the following literature: Wei, Yin, Xue, Zhou, Jinping, Qiao et al. Study the pharmacokinetics of AV-45 in rat plasma and metabolism in liver microsomes by ultra-performance liquid chromatography with mass spectrometry. [J]. Biomed Chromatogr, 2011, 26: 0.

[0130] A total of 182 subjects underwent amyloid positron emission tomography (PET) imaging using 18F-AV45. PET data were captured 50 minutes after intravenous injection of 18F-AV45 10 ± 1 mCi using a SIGNA PET magnetic resonance (MR) device or a Siemens PET computed tomography (CT / MR) device.

[0131] PET subjects were given 10±1mCi of AV45 intravenously and the scan was started after 50 minutes of rest. The acquisition time was 15min. The ordered subset expectation maximization (OSEM) reconstruction algorithm was used, combined with the joint time of flight (TOF) and point spread function (PSF) algorithm to reconstruct the PET images, using 28 subsets and 6 iterations. The zero echo time (ZTE) sequence was used to correct the attenuation of the PET images. The PET image matrix size was 256×256; the DFOV (display field of view) was 46.2cm×30cm; the layer thickness was 2.78mm; and the pixel size was: 2.8mm×2.8mm.

[0132] The PET CT / MR scans were acquired in 15 min using a 3D iterative algorithm (4 iterations and 21 subsets) with a matrix size of 336 × 336, a zoom factor of 2.0 mm, a slice thickness of 2.0 mm, and an all-pass filter. PET image reconstruction used a time-of-flight and point spread function algorithm involving 5 iterations and 16 subsets. The matrix size was 336 × 336, the zoom factor was 2.0, the slice thickness was 2.0 mm, and a Gaussian filter with a full width at half maximum of 5.0 was used.

[0133] PET amyloid visual interpretation: The images were interpreted by 2 professionally trained nuclear medicine physicians. When the 2 physicians disagreed, a senior physician interpreted the image. The image results were divided into positive (mild, moderate or severe) and negative. According to the recommendations of the U.S. Food and Drug Administration (FDA), the scan was classified as "positive" when one or more areas showed increased cortical gray matter signal, resulting in reduced or absent contrast between gray and white matter. When the contrast between gray and white matter was clear, the scan was classified as "negative."

[0134] 3. Statistical analysis

[0135] To determine the ability of plasma markers and their ratios in distinguishing between amyloid-positive and amyloid-negative states, receiver operating characteristic (ROC) curve analysis was performed for pTau217, pTau217 / Aβ1-40, and pTau217 / Aβ1-42 in plasma, and the areas under the curves (AUCs) and 95% confidence intervals of pTau217, pTau217 / Aβ1-40, and pTau217 / Aβ1-42 were calculated; the sensitivity, specificity, false negative rate, and false positive rate were further determined. The optimal threshold (Cut-off value) was determined based on the corresponding maximum Youden J index of the markers. The confusion matrix was calculated by incorporating sensitivity, specificity, positive predictive value (PPA), negative predictive value (NPA), and F1 score to evaluate the classification performance. All statistical analyses were performed in R software version 4.3.2. Statistical significance was defined as α = 0.05, and all tests were two-sided.

[0136] 3. Experimental Results

[0137] 1. Demographic data statistics:

[0138] The SCABI cohort eventually included 182 subjects, including 36 normal elderly people, 120 patients with mild cognitive impairment, and 26 patients with dementia. See Table 1 for specific clinical data collection.

[0139] Table 1. SCABI cohort demographic data (mean ± standard deviation)

[0140]

[0141] 2. Single indicator analysis

[0142] The cut-off value discrimination diagram of pTau217 in plasma of the SCABI cohort is shown in Figure 1 .

[0143] The ROC curve of pTau217 in plasma of the SCABI cohort is shown in Figure 2 .

[0144] The cut-off value discrimination diagram of pTau217 / Aβ1-40 in plasma of the SCABI cohort is shown in Figure 3 .

[0145] The ROC curve of pTau217 / Aβ1-40 in plasma of the SCABI cohort is shown in Figure 4 .

[0146] The cut-off value discrimination diagram of pTau217 / Aβ1-42 in plasma of the SCABI cohort is shown in Figure 5 .

[0147] The ROC curve of pTau217 / Aβ1-42 in plasma of the SCABI cohort is shown in Figure 6 .

[0148] The results of single-indicator analysis of plasma pTau217, Aβ1-40, and Aβ1-42 in the SCABI cohort are shown in Table 2 .

[0149] Table 2. Single index analysis results of plasma markers of pTau217, Aβ1-40, and Aβ1-42 (mean ± standard deviation)

[0150]

[0151] 3. Diagnostic efficacy analysis

[0152] The diagnostic thresholds and diagnostic performance of plasma pTau217, pTau217 / Aβ1-40, and pTau217 / Aβ1-42 in the SCABI cohort are shown in Table 3 .

[0153] Table 3. Cut-off values ​​and diagnostic efficacy of plasma pTau217, pTau217 / Aβ1-40, and pTau217 / Aβ1-42

[0154]

[0155] The results are as follows:

[0156] ① Diagnostic efficacy of plasma pTau217 in identifying patients with Alzheimer's disease

[0157] Establishment of critical value: The area under the ROC curve (AUC) of pTau217 in plasma was 0.946, indicating that this indicator has a high efficacy in distinguishing between amyloid-positive and amyloid-negative individuals. The cut-off value of pTau217 was determined to be 0.242 pg / mL based on the maximum Youden index.

[0158] Verify the diagnostic efficacy of the cut-off value: In the cohort, pTau217 in plasma showed good performance: sensitivity was 0.868 and specificity was 0.934. That is, if the pTau217 in the subject's plasma is greater than 0.242pg / mL (Cut-off value), the subject is likely to have pathological changes of Alzheimer's disease in the brain (high risk of Alzheimer's disease); if the pTau217 in the subject's plasma is 0.242pg / mL or less, the subject is unlikely to have pathological changes of Alzheimer's disease in the brain (low risk of Alzheimer's disease).

[0159] ②The diagnostic efficacy of plasma pTau217 / Aβ1-40 in identifying patients with Alzheimer's disease

[0160] Establishment of critical value: The area under the ROC curve (AUC) of pTau217 / Aβ1-40 in plasma was 0.948, indicating that this indicator has a high efficacy in distinguishing between amyloid-positive and amyloid-negative individuals. The cut-off value of pTau217 / Aβ1-40 was determined to be 0.001 based on the maximum Youden index.

[0161] Verify the diagnostic efficacy of the cut-off value: In the cohort, pTau217 / Aβ1-40 in plasma showed good performance: sensitivity was 0.868 and specificity was 0.981. That is, if the pTau217 / Aβ1-40 in the subject's plasma is greater than 0.001 (Cut-off value), the subject is likely to have pathological changes of Alzheimer's disease in the brain (high risk of Alzheimer's disease); if the pTau217 / Aβ1-40 in the subject's plasma is 0.001 or less, the subject is unlikely to have pathological changes of Alzheimer's disease in the brain (low risk of Alzheimer's disease).

[0162] ③The diagnostic efficacy of plasma pTau217 / Aβ1-42 in identifying patients with Alzheimer's disease

[0163] Establishment of critical value: The area under the ROC curve (AUC) of pTau217 / Aβ1-42 in plasma was 0.959, indicating that this indicator has a high efficacy in distinguishing between amyloid-positive and amyloid-negative individuals. The cut-off value of pTau217 / Aβ1-42 was determined to be 0.012 based on the maximum Youden index.

[0164] Verify the diagnostic efficacy of the cut-off value: In an independent cohort, pTau217 / Aβ1-40 in plasma showed good performance: sensitivity was 0.882 and specificity was 0.981. That is, if the pTau217 / Aβ1-40 in the subject's plasma is greater than 0.012 (Cut-off value), the subject is likely to have pathological changes of Alzheimer's disease in the brain (high risk of Alzheimer's disease); if the pTau217 / Aβ1-40 in the subject's plasma is 0.012 or less, the subject is unlikely to have pathological changes of Alzheimer's disease in the brain (low risk of Alzheimer's disease).

[0165] The present invention has been described in detail above. For those skilled in the art, without departing from the purpose and scope of the present invention, and without the need to carry out unnecessary experimental conditions, the present invention can be implemented in a wide range under equivalent parameters, concentrations and conditions. Although the present invention provides specific embodiments, it should be understood that the present invention can be further improved. In a word, according to the principles of the present invention, the application is intended to include any changes, uses or improvements to the present invention, including departure from the disclosed scope in the application, and changes made with conventional techniques known in the art.

Claims

1. Plasma biomarkers, including pTau217; The detection object of the plasma biomarker is plasma.

2. The plasma biomarker according to claim 1, characterized in that: The plasma biomarkers also include Aβ1-40; Preferably, the plasma biomarker is pTau217 / Aβ1-40; The pTau217 / Aβ1-40 is the concentration ratio of pTau217 and Aβ1-40.

3. The plasma biomarker according to claim 1, characterized in that: The plasma biomarkers also include Aβ1-42; Preferably, the plasma biomarker is pTau217 / Aβ1-42; The pTau217 / Aβ1-42 is the concentration ratio of pTau217 and Aβ1-42.

4. Use of the plasma biomarker according to any one of claims 1 to 3 in the preparation of a product for assessing the risk of Alzheimer's disease or a product for evaluating the possibility of pathological changes of Alzheimer's disease occurring in the brain.

5. Use of Substance A, Substance B or Substance C in the preparation of a product for assessing the risk of developing Alzheimer's disease or a product for assessing the likelihood of developing Alzheimer's pathological changes in the brain; The substance A is a substance used to detect the concentration of pTau217 in plasma; The substance B is a substance used to detect the concentration of pTau217 and Aβ1-40 in plasma; The substance C is a substance used to detect the concentrations of pTau217 and Aβ1-42 in plasma.

6. A data processing device for evaluating the risk of Alzheimer's disease in a subject or evaluating the possibility of pathological changes of Alzheimer's disease in the brain of a subject, which is data processing device 1, data processing device 2 or data processing device 3; The data processing device 1 comprises the following modules: (1) a data receiving module; the data receiving module is configured to receive the content of pTau217 in the plasma of the subject; (2) a data processing module; the data processing module is configured to receive the content of pTau217 in the plasma of the subject from the data receiving module; (3) a data storage module; the data storage module is configured to store the judgment threshold; (4) a data comparison module; the data comparison module is configured to receive pTau217 sent by the data processing module, and call the judgment threshold from the data storage module for comparison with pTau217; (5) a judgment module; the judgment module is configured to receive the comparison result sent by the data comparison module, judge the comparison result according to a predetermined judgment condition, and output the judgment result; The predetermined judgment condition is: if the pTau217 value is greater than the judgment threshold, the subject has a high risk of suffering from Alzheimer's disease or a high possibility of Alzheimer's disease pathological changes in the brain; otherwise, the subject has a low risk of suffering from Alzheimer's disease or a low possibility of Alzheimer's disease pathological changes in the brain; The data processing device 2 includes the following modules: (1) a data receiving module; the data receiving module is configured to receive the content of pTau217 and the content of Aβ1-40 in the plasma of the subject; (2) a data processing module; the data processing module is configured to receive the pTau217 content and the Aβ1-40 content in the plasma of the subject from the data receiving module, and calculate the ratio of the pTau217 content to the Aβ1-40 content, which is recorded as pTau217 / Aβ1-40; (3) a data storage module; the data storage module is configured to store the judgment threshold; (4) a data comparison module; the data comparison module is configured to receive the pTau217 / Aβ1-40 sent by the data processing module, and call the judgment threshold from the data storage module for comparison with the pTau217 / Aβ1-40; (5) a judgment module; the judgment module is configured to receive the comparison result sent by the data comparison module, judge the comparison result according to a predetermined judgment condition, and output the judgment result; The predetermined judgment condition is: if the pTau217 / Aβ1-40 value is greater than the judgment threshold, the subject has a high risk of suffering from Alzheimer's disease or a high possibility of Alzheimer's disease pathological changes in the brain; otherwise, the subject has a low risk of suffering from Alzheimer's disease or a low possibility of Alzheimer's disease pathological changes in the brain; The data processing device 3 includes the following modules: (1) a data receiving module; the data receiving module is configured to receive the content of pTau217 and the content of Aβ1-42 in the plasma of the subject; (2) a data processing module; the data processing module is configured to receive the pTau217 content and the Aβ1-42 content in the plasma of the subject from the data receiving module, and calculate the ratio of the pTau217 content to the Aβ1-42 content, which is recorded as pTau217 / Aβ1-42; (3) a data storage module; the data storage module is configured to store the judgment threshold; (4) a data comparison module; the data comparison module is configured to receive the pTau217 / Aβ1-42 sent by the data processing module, and call the judgment threshold from the data storage module for comparison with the pTau217 / Aβ1-42; (5) a judgment module; the judgment module is configured to receive the comparison result sent by the data comparison module, judge the comparison result according to a predetermined judgment condition, and output the judgment result; The predetermined judgment condition is: if the pTau217 / Aβ1-42 value is greater than the judgment threshold, the subject has a high risk of Alzheimer's disease or a high possibility of pathological changes of Alzheimer's disease in the brain; otherwise, the subject has a low risk of Alzheimer's disease or a low possibility of pathological changes of Alzheimer's disease in the brain.

7. The data processing device according to claim 6, characterized in that: In the data processing device 1, the judgment threshold stored in the data storage module is 0.242 pg / ml; In the data processing device 2, the judgment threshold stored in the data storage module is 0.001; In the data processing device 3, the judgment threshold stored in the data storage module is 0.

012.

8. The data processing device according to claim 6 or 7, characterized in that: In the data processing device 1, the content of pTau217 in the plasma of the subject to be tested received by the data receiving module is obtained according to a method comprising the following steps: collecting peripheral blood of the subject to be tested, separating the plasma, and then detecting the content of pTau217 in the plasma; In the data processing device 2, the content of pTau217 and the content of Aβ1-40 in the plasma of the subject to be tested received by the data receiving module are obtained according to a method comprising the following steps: collecting peripheral blood of the subject to be tested, separating the plasma, and then detecting the content of pTau217 and the content of Aβ1-40 in the plasma; In the data processing device 3, the content of pTau217 and the content of Aβ1-42 in the plasma of the subject to be tested received by the data receiving module are obtained according to a method comprising the following steps: collecting peripheral blood of the subject to be tested, separating the plasma, and then detecting the content of pTau217 and the content of Aβ1-42 in the plasma; The data processing device further comprises a control module or a controller; the control module or the controller is used to control each module.

9. A system for assessing the risk of developing Alzheimer's disease or the possibility of pathological changes of Alzheimer's disease in the brain, comprising control device 1, control device 2 or control device 3; The control device 1 is configured or programmed to perform the following steps: Receiving the content of pTau217 in the plasma of the subject to be tested; Comparing the pTau217 content in the plasma of the subject to be tested with the judgment threshold value to obtain a comparison result; Determine the comparison result according to a predetermined determination condition and output the determination result; The predetermined judgment condition is: if the pTau217 value is greater than the judgment threshold, the subject has a high risk of suffering from Alzheimer's disease or a high possibility of Alzheimer's disease pathological changes in the brain; otherwise, the subject has a low risk of suffering from Alzheimer's disease or a low possibility of Alzheimer's disease pathological changes in the brain; The system including the control device 1 further includes an input device and an output device; the input device is configured to input the content of pTau217 in the plasma of the subject to be tested; the output device is configured to output the determination result; The control device 2 is configured or programmed to perform the following steps: Receiving the content of pTau217 and Aβ1-40 in the plasma of the subject to be tested; According to the content of pTau217 and the content of Aβ1-40 in the plasma of the test subject, the ratio of the content of pTau217 to the content of Aβ1-40 is calculated, and recorded as pTau217 / Aβ1-40; Comparing the pTau217 / Aβ1-40 in the plasma of the subject to be tested with the judgment threshold to obtain a comparison result; Determine the comparison result according to a predetermined determination condition and output the determination result; The predetermined judgment condition is: if the pTau217 / Aβ1-40 value is greater than the judgment threshold, the subject has a high risk of suffering from Alzheimer's disease or a high possibility of Alzheimer's disease pathological changes in the brain; otherwise, the subject has a low risk of suffering from Alzheimer's disease or a low possibility of Alzheimer's disease pathological changes in the brain; The system including the control device 2 further includes an input device and an output device; the input device is configured to input the content of pTau217 and the content of Aβ1-40 in the plasma of the subject to be tested; the output device is configured to output the determination result; The control device 3 is configured or programmed to perform the following steps: Receiving the content of pTau217 and Aβ1-42 in the plasma of the subject to be tested; According to the content of pTau217 and the content of Aβ1-42 in the plasma of the test subject, the ratio of the content of pTau217 to the content of Aβ1-42 is calculated, and recorded as pTau217 / Aβ1-42; Comparing the pTau217 / Aβ1-42 in the plasma of the subject to be tested with the judgment threshold to obtain a comparison result; Determine the comparison result according to a predetermined determination condition and output the determination result; The predetermined judgment condition is: if the pTau217 / Aβ1-42 value is greater than the judgment threshold, the subject has a high risk of Alzheimer's disease or a high possibility of pathological changes of Alzheimer's disease in the brain; otherwise, the subject has a low risk of Alzheimer's disease or a low possibility of pathological changes of Alzheimer's disease in the brain; The system including the control device 3 also includes an input device and an output device; the input device is configured to input the content of pTau217 and the content of Aβ1-42 in the plasma of the subject to be tested; and the output device is configured to output the determination result.

10. A computer-readable storage medium storing a computer program for executing the following steps: The steps are step 1, step 2 or step 3: The step 1 is: Receiving the content of pTau217 in the plasma of the subject to be tested; Comparing the pTau217 content in the plasma of the subject to be tested with the judgment threshold value to obtain a comparison result; Determine the comparison result according to a predetermined determination condition and output the determination result; The predetermined judgment condition is: if the pTau217 value is greater than the judgment threshold, the subject has a high risk of suffering from Alzheimer's disease or a high possibility of Alzheimer's disease pathological changes in the brain; otherwise, the subject has a low risk of suffering from Alzheimer's disease or a low possibility of Alzheimer's disease pathological changes in the brain; The system including the control device 1 further includes an input device and an output device; the input device is configured to input the content of pTau217 in the plasma of the subject to be tested; the output device is configured to output the determination result; The step 2 is: Receiving the content of pTau217 and Aβ1-40 in the plasma of the subject to be tested; According to the content of pTau217 and the content of Aβ1-40 in the plasma of the test subject, the ratio of the content of pTau217 to the content of Aβ1-40 is calculated, and recorded as pTau217 / Aβ1-40; Comparing the pTau217 / Aβ1-40 in the plasma of the subject to be tested with the judgment threshold to obtain a comparison result; Determine the comparison result according to a predetermined determination condition and output the determination result; The predetermined judgment condition is: if the pTau217 / Aβ1-40 value is greater than the judgment threshold, the subject has a high risk of suffering from Alzheimer's disease or a high possibility of Alzheimer's disease pathological changes in the brain; otherwise, the subject has a low risk of suffering from Alzheimer's disease or a low possibility of Alzheimer's disease pathological changes in the brain; The step 3 is: Receiving the content of pTau217 and Aβ1-42 in the plasma of the subject to be tested; According to the content of pTau217 and the content of Aβ1-42 in the plasma of the test subject, the ratio of the content of pTau217 to the content of Aβ1-42 is calculated, and recorded as pTau217 / Aβ1-42; Comparing the pTau217 / Aβ1-42 in the plasma of the subject to be tested with the judgment threshold to obtain a comparison result; Determine the comparison result according to a predetermined determination condition and output the determination result; The predetermined judgment condition is: if the pTau217 / Aβ1-42 value is greater than the judgment threshold, the subject has a high risk of Alzheimer's disease or a high possibility of pathological changes of Alzheimer's disease in the brain; otherwise, the subject has a low risk of Alzheimer's disease or a low possibility of pathological changes of Alzheimer's disease in the brain.

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