Qualitative and absolute quantitative detection method of M protein, electronic equipment and storage medium

Abstract

The invention relates to the technical field of sample detection, in particular to a qualitative and quantitative detection method of M protein, electronic equipment and a storage medium. The qualitative and quantitative detection method for the M protein comprises the following steps: acquiring a mass spectrum of a sample to be detected; the mass spectrum at least comprises a total light chain region; carrying out peak value detection on the mass spectrum, and judging whether M protein peaks exist in the total light chain region or not; and for the mass spectrum with the M protein peak, calculating the curve lower peak area SM of the M protein peak and the curve lower peak area SLC of the total light chain region, and combining a serum total immunoglobulin quantitative result or a serum total light chain quantitative result to obtain the absolute content MW of the M protein. The method provided by the invention can realize absolute quantitative detection of the M protein, and solves the problem that absolute quantitative detection cannot be carried out on the M protein in the prior art.

Description

Technical Field

[0001] The present invention relates to the technical field of sample detection, and in particular to a qualitative and absolute quantitative detection method of M protein, an electronic device and a storage medium. Background Art

[0002] At present, monoclonal immunoglobulin (M protein) in serum is an important biomarker that can be used to screen for multiple myeloma, chronic lymphocytic leukemia and other diseases. When detecting M protein in serum, MALDI-TOF mass spectrometry (non-antibody enrichment) is more sensitive, rapid and low-cost than serum protein electrophoresis (PEL), immunofixation electrophoresis (IFE), serum free light chain (FLC) and other methods.

[0003] The existing MALDI-TOF mass spectrometry relies on the identification and interpretation of M protein peaks, mainly in the following two ways:

[0004] Method 1: After the serum is diluted and restored, the total light chains in the serum are qualitatively detected by comparing the mass spectrum of the target sample with the negative mass spectrum of the M protein of a healthy person and visually inspecting it manually. If an obvious peak appears in the range of the single and double charged mass-to-charge ratios of the κ and λ light chains, it is determined that the serum sample to be tested contains M protein.

[0005] Method 2: After the serum is diluted and restored, the total light chains in the serum are qualitatively detected to provide the mass-to-charge ratio distribution data of the single-charged ions of the immunoglobulin light chains (including λ light chains and κ light chains) in the test sample. If the light chain mass-to-charge ratio range has a narrow base, high peak and sharp mass spectrum peak, it is determined that the test sample contains M protein; if the peak area ratio of the κ light chain to the λ light chain is less than 1.8 or greater than 3.5, and the peak shape is a non-Gaussian distribution, it is determined that the test sample contains M protein.

[0006] Among them, the problems with method 1 include: the mass spectrometry peak of the M protein light chain of weakly positive or double-positive patients is usually of low intensity, and no obvious mass spectrometry peak can be observed, which is easy to miss; the spectrum to be tested needs to be superimposed and compared with the M protein negative spectrum, which is difficult to automate; the visual interpretation results will be affected by human experience and subjective factors, and consistency cannot be guaranteed; visual interpretation is difficult to apply to large-scale screening of diseases; and quantitative information cannot be given.

[0007] Problems with method 2 include: the mass spectrometry peak of the M protein light chain of weakly positive or double-positive patients is usually of low intensity, and the mass spectrometry peak area ratio of the κ light chain to the λ light chain may be within the normal range. It is unable to identify M proteins with low peak intensity and mass spectrometry peak area ratio of the κ light chain to the λ light chain within the normal range, and has low sensitivity; machine learning is used to determine whether the mass spectrometry peak shape is a Gaussian distribution, which requires the collection of a large number of samples for training, and the process is complicated and time-consuming; quantitative information cannot be given.

[0008] In order to overcome the above-mentioned defects, the applicant filed an invention patent application entitled "M protein detection method, electronic device and storage medium" (CN117849159A) on January 9, 2024, which discloses a method for detecting M protein, electronic device and storage medium. The method comprises: obtaining mass spectrometry data of the sample to be detected, wherein the mass spectrometry data includes at least a first preset interval and a second preset interval, the first preset interval is the distribution interval of the λ light chain in the mass spectrometry data, and the second preset interval is the distribution interval of the κ light chain in the mass spectrometry data; performing peak detection on the mass spectrometry data to determine whether there is a mass spectrometry peak in the first preset interval and the second preset interval; obtaining the detection result of the M protein based on the peak detection result and / or the average intensity of the mass spectrometry data in the first preset interval and the second preset interval.

[0009] However, the above method still has some deviations and cannot achieve absolute quantitative detection of M protein; and, for glycosylated M protein, absolute quantitative detection cannot be achieved.

[0010] Accordingly, the art needs a new technical solution to solve the above problems. Summary of the invention

[0011] In order to overcome the above-mentioned defects, the present application provides a qualitative and absolute quantitative detection method of M protein, an electronic device and a storage medium to solve or at least partially solve the technical problem of how to achieve absolute quantitative detection of M protein and / or glycosylated M protein.

[0012] In a first aspect, the present invention provides a method for qualitative and absolute quantitative detection of M protein, wherein the method comprises:

[0013] Obtaining a mass spectrum of the sample to be tested, wherein the mass spectrum at least includes a total light chain region;

[0014] Performing peak detection on the mass spectrum to determine whether an M protein peak exists in the total light chain region;

[0015] For the mass spectrum with M protein peak, calculate the peak area under the curve S of M protein peak M The peak area under the curve S LC Combined with the quantitative results of serum total immunoglobulin or serum total light chain, the absolute content of M protein is obtained. W .

[0016] In the preferred technical scheme of the qualitative and absolute quantitative detection method of the M protein, the absolute content of the M protein is obtained by combining the quantitative results of the total serum immunoglobulin or the total serum light chain. W ,include:

[0017] Based on the calculated peak area under the curve S of the M protein peak M The peak area under the curve S LC , the relative abundance of M protein was obtained as M%;

[0018] Based on the relative abundance M% of M protein, combined with the quantitative results of serum total immunoglobulin or serum total light chain, the absolute content M of M protein was obtained. W .

[0019] In the preferred technical solution of the qualitative and absolute quantitative detection method of the M protein, the relative abundance M% of the M protein is calculated according to the following formula:

[0020] In the preferred technical solution of the qualitative and absolute quantitative detection method of M protein, the absolute content of M protein is W Calculated according to the following formula: M W =TotalIg×M% or M W =TotalIgLC×M%

[0021] Where:

[0022] TotalIg——serum total immunoglobulin quantitative results;

[0023] TotalIgLC——serum total light chain quantitative results.

[0024] In the preferred technical solution of the above-mentioned qualitative and absolute quantitative detection method of M protein, the mass spectrum also includes the light chain glycosylation region;

[0025] The qualitative and quantitative detection method further comprises: performing glycosylation detection on the light chain glycosylation region to obtain a glycosylation detection result.

[0026] In the preferred technical solution of the qualitative and absolute quantitative detection method of the above-mentioned M protein, the glycosylation detection of the light chain glycosylation region to obtain the glycosylation detection result comprises:

[0027] Performing peak detection on the mass spectrum to determine whether there is a glycosylated M protein peak in the light chain glycosylation region;

[0028] For the mass spectrum of the glycosylated M protein peak, calculate the peak area under the curve S of the glycosylated M protein peak. MG The peak area under the curve S LC Combined with the quantitative results of serum total immunoglobulin or serum total light chain, the absolute content of glycosylated M protein was obtained. WG .

[0029] In the preferred technical scheme of the qualitative and absolute quantitative detection method of the M protein, the absolute content M of the glycosylated M protein is obtained by combining the quantitative results of the total serum immunoglobulin or the total serum light chain. WG ,include:

[0030] Based on the calculated peak area under the curve of the glycosylated M protein peak S MG The peak area under the curve S LC , and the relative abundance of glycosylated M protein was obtained. G %;

[0031] Relative abundance of M proteins based on glycosylation modification G %, combined with the quantitative results of serum total immunoglobulin or serum total light chain, the absolute content of glycosylated M protein was obtained. WG .

[0032] In the preferred technical solution of the above-mentioned qualitative and absolute quantitative detection method of M protein, the relative abundance M of glycosylated M protein is G % is calculated according to the following formula:

[0033] The absolute content of glycosylated M protein WG Calculated according to the following formula: M WG =TotalIg×M G % or M WG =TotalIgLC×M G %

[0034] Where:

[0035] TotalIg——serum total immunoglobulin quantitative results;

[0036] TotalIgLC——serum total light chain quantitative results.

[0037] In the preferred technical solution of the qualitative and absolute quantitative detection method of the M protein, the peak area under the curve S of the M protein peak is M , the peak area under the curve of the total light chain region S LC and the peak area under the curve of the glycosylated M protein peak S MG The following method is used to obtain:

[0038] The starting point and the end point of each peak are selected respectively, and the area under the curve of each peak is definite integrally performed by the oblique cutting method. The definite integral result of each peak is the peak area under the curve of each peak.

[0039] In the preferred technical solution of the qualitative and absolute quantitative detection method of the M protein, the definite integral of the area under the curve of each peak by oblique cutting comprises:

[0040] After selecting the starting point and end point of the peak, establish the linear equation y=ax+b using the X-axis and Y-axis coordinates of the two points;

[0041] Differentiate the curve in the peak region, take a single bin as the smallest structural unit, and obtain the starting and ending coordinates of each bin [X a , Y a ]、[X b , Y b ];

[0042] Substitute the X-axis coordinates of the starting point and the end point into the above linear equation to obtain the X-axis and Y-axis coordinates of the two intersection points, and calculate the peak area under the curve of the peak according to the following definite integral formula:

[0043] Where: S represents the peak area under the curve, is the symbol of the definite integral, representing the integral from a to b, while f(x) is the integrand, representing the shape of the curve.

[0044] In a second aspect, the present invention provides an electronic device comprising a processor and a storage device, wherein the storage device is suitable for storing a plurality of program codes, wherein the program codes are suitable for being loaded and run by the processor to execute the above-mentioned qualitative and absolute quantitative detection methods of M protein.

[0045] In a third aspect, the present invention provides a computer-readable storage medium storing a plurality of program codes, wherein the program codes are suitable for being loaded and run by a processor to execute the above-mentioned qualitative and absolute quantitative detection methods of M protein.

[0046] Compared with the prior art, the present invention has the following beneficial effects:

[0047] 1. The present invention has established a complete method for accurate qualitative and absolute quantitative analysis of M protein in serum and qualitative and absolute quantitative analysis of immunoglobulin light chain glycosylation, so as to solve the problem that the absolute quantitative analysis of M protein in serum cannot be achieved;

[0048] 2. The method of the present invention significantly improves the precision of quantitative analysis of M protein, especially absolute quantification of low-concentration M protein. The successful development of this methodology is expected to be applied to large-scale clinical screening and clinical follow-up monitoring of M protein in serum.

[0049] 3. Compared with the existing electrophoresis method, the present invention greatly shortens the pre-treatment time of a single sample, improves the absolute quantitative sensitivity and precision of M protein, and effectively solves the problems of low accuracy, low detection flux, poor specificity and sensitivity, and poor quantitative precision in the detection of serum M protein by the existing method. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] Figure 1 A schematic diagram of mass spectrometry peaks of an M protein negative sample;

[0051] Figure 2 A schematic diagram of the mass spectrometry peaks of an M protein positive sample;

[0052] Figure 3 A schematic diagram of the mass spectrometry peaks of a weakly positive sample of M protein;

[0053] Figure 4 Schematic diagram of the main steps of the qualitative and absolute quantitative detection method of M protein;

[0054] Figure 5 A schematic diagram of the main steps of peak detection in mass spectra;

[0055] Figure 6 Schematic diagram of the main steps for determining whether there is an M protein peak in the total light chain region;

[0056] Figure 7 This is a schematic diagram of the qualitative results of a sample with positive M protein glycosylation;

[0057] Figure 8 It is a schematic diagram of calculating the peak area under the curve by using the oblique cutting method;

[0058] Fig. 9 This is a schematic diagram of calculating the peak area under the curve of each peak of the M protein positive sample using the oblique cutting method in Example 1;

[0059] Fig.10 This is a schematic diagram of calculating the peak area under the curve of each peak of the M protein glycosylation positive sample using the oblique cutting method in Example 2. DETAILED DESCRIPTION

[0060] The preferred embodiments of the present invention are described below in conjunction with the accompanying drawings. It should be understood by those skilled in the art that these embodiments are only used to explain the technical principles of the present invention and are not intended to limit the protection scope of the present invention.

[0061] In the description of this application, "processor" may include hardware, software or a combination of the two. The processor may be a central processing unit, a microprocessor, an image processor, a digital signal processor or any other suitable processor. The processor has data and / or signal processing functions. The processor may be implemented in software, hardware or a combination of the two. Non-temporary computer-readable storage media include any suitable media that can store program codes, such as magnetic disks, hard disks, optical disks, flash memories, read-only memories, random access memories, etc. The term "and / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B may represent: A exists alone, A and B exist at the same time, and B exists alone. Among them, A and B may be singular or plural. The character " / " generally indicates that the objects associated before and after are in an "or" relationship.

[0062] In this application, "at least one" means one or more, and "plurality" means two or more. "At least one of the following" or similar expressions refers to any combination of these items, including any combination of single items or plural items. For example, "at least one of a, b, or c", or "at least one of a, b, and c" can all mean: a, b, c, ab (i.e., a and b), ac, bc, or abc, where a, b, c can be single or multiple, respectively.

[0063] It should be understood that in various embodiments of the present application, the above-mentioned order of steps does not mean the order of execution, and some or all of the steps can be executed in parallel or sequentially. For example, step S1 can be executed at any node before executing step S8, step S9, and step S10, or step S8, step S9 and step S10 can be executed simultaneously or in sequence in any order. The execution order of each step should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0064] The terms used in the embodiments of the present application are only for the purpose of describing specific embodiments, and are not intended to limit the present application. The singular forms "a", "said" and "the" used in the embodiments of the present application and the appended claims are also intended to include plural forms, unless the context clearly indicates other meanings.

[0065] The weight of the relevant components mentioned in the embodiment description of the present application can not only refer to the specific content of each component, but also represent the proportional relationship between the weights of the components. Therefore, as long as the content of the relevant components is proportionally enlarged or reduced according to the embodiment description of the present application, it is within the scope disclosed in the embodiment description of the present application. Specifically, the mass described in the embodiment description of the present application can be a mass unit known in the chemical industry such as μg, mg, g, kg, etc.

[0066] The terms "first" and "second" are used only for descriptive purposes to distinguish objects such as substances from each other, and should not be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features. For example, without departing from the scope of the embodiments of the present application, the first XX may also be referred to as the second XX, and similarly, the second XX may also be referred to as the first XX. Thus, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features.

[0067] The experimental methods in the following examples are conventional methods unless otherwise specified, and the materials, reagents, etc. used in the following examples are commercially available unless otherwise specified.

[0068] MALDI-TOF mass spectrometry relies on the identification and interpretation of M protein peaks. Through a large number of sample analysis statistics, it was found that the mass spectrum peaks of M protein-negative samples have a relatively standard Gaussian distribution, while the mass spectrum peaks of M protein-positive samples have non-Gaussian distribution peaks. Figure 1 , Figure 2 and Figure 3 . Figure 1 is a schematic diagram of mass spectrometry peaks of an M protein negative sample of the present invention, Figure 2 is a schematic diagram of mass spectrometry peaks of an M protein positive sample of the present invention, Figure 3 It is a schematic diagram of the mass spectrum peak of a weakly positive sample of M protein in the present invention.

[0069] In order to solve the problem pointed out in the background technology that the existing MALDI-TOF mass spectrometry has some deviations and cannot achieve absolute quantitative detection of M protein and / or glycosylated M protein, the present invention provides a qualitative and absolute quantitative detection method, electronic device and storage medium of M protein.

[0070] Specifically, the flow chart of the qualitative and absolute quantitative detection method of M protein provided by the present invention is as follows: Figure 4 As shown, it mainly includes the following steps S1 to S3:

[0071] Step S1, obtaining a mass spectrum of the sample to be tested; the mass spectrum at least includes a total light chain region;

[0072] Step S2, performing peak detection on the mass spectrum to determine whether there is an M protein peak in the total light chain region;

[0073] Step S3: for the mass spectrum with M protein peak, calculate the peak area S under the curve of M protein peak. M The peak area under the curve S LC Combined with the quantitative results of serum total immunoglobulin or serum total light chain, the absolute content of M protein is obtained. W .

[0074] In the present application, after identifying the M protein light chain mass spectrometry peak of positive, weakly positive or double positive patients through steps S1 and S2, step S3 is used to obtain the absolute content of M protein, thereby achieving absolute quantitative detection of M protein, solving the problem that absolute quantitative detection of M protein cannot be performed in the prior art.

[0075] In some specific embodiments, in step S3, the absolute content M of M protein is obtained by combining the quantitative results of serum total immunoglobulin or serum total light chain. W ,include:

[0076] S31, based on the calculated peak area under the curve of the M protein peak S M The peak area under the curve S LC , the relative abundance of M protein was obtained as M%;

[0077] S32. Based on the relative abundance M% of M protein, combined with the quantitative results of serum total immunoglobulin or serum total light chain, the absolute content M of M protein is obtained. W .

[0078] At present, the existing methods can only achieve relative quantitative detection of M protein, but cannot achieve absolute quantitative detection thereof. The present application can achieve absolute quantitative detection of M protein through the above scheme, solving the problem that the prior art cannot achieve absolute quantitative detection of M protein.

[0079] In some embodiments, the relative abundance M% of the M protein is calculated according to the following formula:

[0080] In some embodiments, the absolute content of M protein is W Calculated according to the following formula: M W =TotalIg×M% or M W =TotalIgLC×M%

[0081] Where:

[0082] TotalIg——serum total immunoglobulin quantitative results;

[0083] TotalIgLC——serum total light chain quantitative results.

[0084] It should be noted that, in the present application, the quantitative results of total serum immunoglobulin or total serum light chain are measured by biochemical or protein analyzer.

[0085] In this application, the mass-to-charge ratio distribution of the singly charged ions in the total light chain region is: [M+H] + m / z(Da)22200~24600.

[0086] The above total light chain region includes a λ light chain region and a κ light chain region, wherein:

[0087] Lambda light chain region: [M+H] + m / z(Da)22200~23100;

[0088] κ light chain region: [M+H] + m / z(Da)23100~24600.

[0089] In the above step S1 of the present application, the mass spectrum of the sample to be detected can be obtained by referring to the method of the prior art, such as loading the sample to be detected into a mass spectrometer after pretreatment, and setting the acquisition conditions of the mass spectrometer to obtain the mass spectrum.

[0090] Specifically, the preprocessing may include the following steps:

[0091] (1) diluting the sample to be tested with a buffer solution (such as deionized water, PBS solution, etc., and PBS solution is selected in the present invention) to obtain a sample dilution solution;

[0092] (2) adding a reducing agent (such as dithiothreitol, tris(2-carboxyethyl)phosphine, etc., in the present invention, tris(2-carboxyethyl)phosphine) to the sample diluent, incubating at room temperature for 10 minutes to reduce, and obtaining a sample reduction solution;

[0093] (3) Take 5 μl of sample reduction solution, mix it with 10-20 μl of matrix solution (such as sinapinic acid, α-cyano-4-hydroxycinnamic acid, dihydroxybenzoic acid, etc., and the present invention selects 20 μl of sinapinic acid), and take 2.5 μl and apply it to the sample chip, which is placed on a 40°C heating plate and heated to dry.

[0094] The acquisition conditions of the mass spectrometer can be set as follows: laser energy 5-25 μJ, detector voltage 0.4-0.8 kV, focus mass 20000-25000 Da, scan speed 0.5-5 mm / s, scan range 2000-200000 Da.

[0095] In the above step S2 of the present application, a continuous wavelet transform peak detection method can be used for peak detection of the mass spectrum. Figure 5 The main steps of performing peak detection on a mass spectrum are shown, including the following steps S211 to S212:

[0096] Step S211, obtaining continuous wavelet transform peak detection parameters;

[0097] Step S212: performing continuous wavelet transform peak detection on the mass spectrum data based on the continuous wavelet transform peak parameters.

[0098] In step S2 of the present application, the judgment on whether the M protein peak exists is specifically as follows: for the mass spectrum graph in which the mass spectrum peak exists in the total light chain region, the position and intensity of each mass spectrum peak are obtained, and the proportionality coefficient is calculated based on the intensity of each mass spectrum peak and the average intensity of the mass spectrum data, and whether the sample to be tested contains M protein is judged based on whether there is at least one proportionality coefficient greater than or equal to the proportionality coefficient threshold value. Figure 6 The main steps of determining whether there is an M protein peak in the total light chain region are shown, including the following steps S221 to S222:

[0099] Step S221, obtaining a proportionality coefficient between the intensity of each mass spectrum peak in the total light chain region and the average intensity of the mass spectrum data;

[0100] Step S222: Determine whether the sample to be tested contains M protein based on whether there is at least one proportionality coefficient greater than or equal to the proportionality coefficient threshold value.

[0101] In step S222, if the result is yes, it is determined that the sample to be detected contains M protein; if the result is no, it is determined that the sample to be detected does not contain M protein.

[0102] The intensity of each mass spectral peak in the total light chain region can be directly obtained from the peak list.

[0103] In the peak list, in the lambda light chain region ([M+H] + If there is a mass spectrum peak within the range of m / z 22200~23100Da), it is judged as positive for λ-type M protein.

[0104] In the peak list, in the κ light chain region ([M+H] + If there is a mass spectrum peak within the range of m / z 23100~24600Da), it is judged as positive for κ-type M protein.

[0105] If there are mass spectrometry peaks in both the λ light chain region and the κ light chain region in the peak list, it is determined to be double positive for λ-type and κ-type M protein.

[0106] Specifically, when executing the above step S2, it can be performed according to the method described in CN117849159A.

[0107] In some embodiments, the mass spectrum further includes a light chain glycosylation region;

[0108] In some specific embodiments, the qualitative and quantitative detection method of the M protein provided in the present application further comprises: performing glycosylation detection on the light chain glycosylation region to obtain a glycosylation detection result.

[0109] In this application, the mass-to-charge ratio distribution of the single-charged ions in the light chain glycosylation region is: [M+H] + m / z(Da)24500~27800.

[0110] In some specific embodiments, the performing glycosylation detection on the light chain glycosylation region to obtain the glycosylation detection result comprises:

[0111] Performing peak detection on the data of the mass spectrum to determine whether there is a glycosylated M protein peak in the light chain glycosylation region;

[0112] For the mass spectrum of the glycosylated M protein peak, calculate the peak area under the curve S of the glycosylated M protein peak. MG The peak area under the curve S LC Combined with the quantitative results of serum total immunoglobulin or serum total light chain, the absolute content of glycosylated M protein was obtained. WG .

[0113] Specifically, when determining whether the light chain glycosylation region has a glycosylated M protein peak, the pre-set continuous wavelet transform peak detection parameters can be obtained to perform peak detection on the mass spectrum data to determine whether the light chain glycosylation region has a glycosylated M protein peak. The specific process can be performed according to the method described in CN117849159A.

[0114] Figure 7 It is a schematic diagram of the qualitative results of an M protein glycosylation-positive sample of the present invention.

[0115] Further, after the glycosylated M protein peak is detected in the sample to be tested, the peak area under the curve S of the glycosylated M protein peak is calculated. MG The peak area under the curve S LC Combined with the quantitative results of serum total immunoglobulin or serum total light chain, the absolute content of glycosylated M protein was obtained. WG .

[0116] In some specific embodiments, the absolute content M of glycosylated M protein is obtained by combining the quantitative results of serum total immunoglobulin or serum total light chain.WG ,include:

[0117] Based on the calculated peak area under the curve of the glycosylated M protein peak S MG The peak area under the curve S LC , and the relative abundance of glycosylated M protein was obtained. G %;

[0118] Relative abundance of M proteins based on glycosylation modification G %, combined with the quantitative results of serum total immunoglobulin or serum total light chain, the absolute content of glycosylated M protein was obtained. WG .

[0119] The present application can not only realize the absolute quantitative detection of M protein for the sample to be detected, but also realize the absolute quantitative detection of immunoglobulin light chain glycosylation.

[0120] In some embodiments, the relative abundance of glycosylated M protein is G % is calculated according to the following formula:

[0121] The absolute content of glycosylated M protein WG Calculated according to the following formula: M WG =TotalIg×M G % or M WG =TotalIgLC×M G %

[0122] Where:

[0123] TotalIg——serum total immunoglobulin quantitative results;

[0124] TotalIgLC——serum total light chain quantitative results.

[0125] In some embodiments, the peak area under the curve of the M protein peak is M , the peak area under the curve of the total light chain region S LC and the peak area under the curve of the glycosylated M protein peak S MG The following method is used to obtain:

[0126] The starting point and the end point of each peak are selected respectively, and the area under the curve of each peak is definite integrally performed by the oblique cutting method. The definite integral result of each peak is the peak area under the curve of each peak.

[0127] Compared with the vertical baseline integration method, the present invention adopts an oblique cutting method to perform definite integration of the area under the curve of each peak, avoiding the interference of the polyclonal immunoglobulin background, thereby making the result more accurate.

[0128] Furthermore, after obtaining a more accurate relative content of M protein or glycosylated M protein based on the mass spectrometer, the present invention combines the clinical serum total immunoglobulin or serum total light chain quantitative results to obtain the absolute content of M protein or glycosylated M protein, thereby achieving absolute quantitative detection of M protein or glycosylated M protein, and solving the problem that M protein or glycosylated M protein cannot be absolutely quantitatively detected in the prior art.

[0129] In some specific embodiments, the step of performing a definite integral on the area under the curve of each peak by using a bevel cutting method comprises:

[0130] After selecting the starting point and end point of the peak, establish the linear equation y=ax+b using the X-axis and Y-axis coordinates of the two points;

[0131] Differentiate the curve in the peak region, take a single bin as the smallest structural unit, and obtain the starting and ending coordinates of each bin [X a , Y a ]、[X b , Y b ];

[0132] Substitute the X-axis coordinates of the starting point and the end point into the above linear equation to obtain the X-axis and Y-axis coordinates of the two intersection points, and calculate the area under the curve of the peak according to the following definite integral formula:

[0133] Where: S represents the area under the peak curve, is the symbol of the definite integral, representing the integral from a to b, while f(x) is the integrand, representing the shape of the curve.

[0134] For the schematic diagram of calculating the peak area under the curve of each peak using the above-mentioned oblique cutting method, please refer to Figure 8 .

[0135] It is understood by those skilled in the art that all or part of the processes in the method for implementing the above-mentioned embodiment of the present application can also be completed by instructing the relevant hardware through a computer program, and the computer program can be stored in a computer-readable storage medium, and the computer program can implement the steps of the above-mentioned various method embodiments when executed by the processor. Among them, the computer program includes computer program code, and the computer program code can be in source code form, object code form, executable file or some intermediate form. The computer-readable storage medium may include: any entity or device, medium, U disk, mobile hard disk, disk, optical disk, computer memory, read-only memory, random access memory, electric carrier signal, telecommunication signal and software distribution medium, etc. that can carry the computer program code.

[0136] In a second aspect, the present invention also provides an electronic device. The electronic device in the embodiment of the present invention mainly includes a processor and a storage device, the storage device can be configured to execute the program of the qualitative and absolute quantitative detection method of the M protein of the above method embodiment, and the processor can be configured to execute the program in the storage device, which includes but is not limited to the program of the qualitative and absolute quantitative detection method of the M protein of the above method embodiment. For ease of explanation, only the part related to the embodiment of the present invention is shown. For specific technical details not disclosed, please refer to the method part of the embodiment of the present invention.

[0137] In some possible embodiments of the present invention, the electronic device may include multiple processors and multiple storage devices. The program for executing the qualitative and absolute quantitative detection method of the M protein of the above method embodiment can be divided into multiple subprograms, and each subprogram can be loaded and run by the processor to execute the different steps of the qualitative and absolute quantitative detection method of the M protein of the above method embodiment. Specifically, each subprogram can be stored in different storage devices, and each processor can be configured to execute the program in one or more storage devices to jointly implement the qualitative and absolute quantitative detection method of the M protein of the above method embodiment, that is, each processor executes the different steps of the qualitative and absolute quantitative detection method of the M protein of the above method embodiment, to jointly implement the qualitative and absolute quantitative detection method of the M protein of the above method embodiment.

[0138] The above-mentioned multiple processors may be processors deployed on the same device. For example, the above-mentioned electronic device may be a high-performance device composed of multiple processors, and the above-mentioned multiple processors may be processors configured in the high-performance device. In addition, the above-mentioned multiple processors may also be processors deployed on different devices. For example, the above-mentioned electronic device may be a server cluster, and the above-mentioned multiple processors may be processors on different servers in the server cluster.

[0139] In a third aspect, the present application also provides a computer-readable storage medium. In a computer-readable storage medium embodiment according to the present invention, the computer-readable storage medium can be configured to store a program for executing the qualitative and absolute quantitative detection method of the M protein of the above-mentioned method embodiment, and the program can be loaded and run by the processor to implement the above-mentioned qualitative and absolute quantitative detection method of the M protein. For ease of explanation, only the part related to the embodiment of the present invention is shown. For specific technical details not disclosed, please refer to the method part of the embodiment of the present invention. The computer-readable storage medium can be a storage device formed by various electronic devices. Optionally, the computer-readable medium in the embodiment of the present invention is a non-temporary computer-readable storage medium.

[0140] Example 1

[0141] like Fig. 9 As shown, the sample to be tested in this embodiment is judged as M protein positive through peak detection after preprocessing and data acquisition to obtain a mass spectrum, that is, there is an M protein peak in the total light chain region. The specific method is the same as described above.

[0142] After analysis by biochemical analyzer, the quantitative result of serum immunoglobulin of the sample to be tested was 13.17g / L.

[0143] The absolute quantitative calculation of the content of M protein in the sample to be tested is as follows:

[0144] Select the starting point and end point of the M protein peak, and establish a linear equation y=ax+b using the X-axis and Y-axis coordinates of the two points;

[0145] Differentiate the curve in the region, take a single bin as the smallest structural unit, and obtain the starting and ending coordinates of each bin [X a , Y a ]、[X b , Y b ];

[0146] Substituting the X-axis coordinates of the starting point and the end point into the above linear equation, we can get the X-axis and Y-axis coordinates of the two intersection points. Since this area can be regarded as having only one peak, we can calculate this area according to the following definite integral formula ( Fig. 9 The area of ​​the green area is S M :

[0147] Where: S M represents the area under the curve of the M protein peak, is the symbol of the definite integral, representing the integral from a to b, while f(x) is the integrand, representing the shape of the curve.

[0148] As above, the starting point and end point of the total light chain region of immunoglobulin were selected, and the region ( Fig. 9 The area of ​​the red area is S LC :

[0149] Based on the calculated peak area under the curve S of the M protein peak M The peak area under the curve S LC , the relative abundance M% of M protein was obtained according to the following formula:

[0150] Based on the relative abundance M% of M protein and the quantitative results of serum immunoglobulin, the absolute content of M protein was calculated, namely:

[0151] M W (g / L)=TotalIg×M%=13.17(g / L)×16.49%=2.17(g / L)

[0152] Example 2

[0153] like Fig.10 As shown, the sample to be tested in this embodiment is pre-processed, data collected to obtain a mass spectrum, and then peak detected to be positive for M protein glycosylation, that is, there is a glycosylated M protein peak. The specific method is the same as described above.

[0154] After analysis by biochemical analyzer, the quantitative result of serum immunoglobulin of the sample to be tested was 29.56g / L.

[0155] The absolute quantitative calculation of the content of glycosylated M protein in the sample to be tested is as follows:

[0156] The starting point and the end point of the glycosylated M protein peak were selected, and the linear equation y=ax+b was established with the X-axis and Y-axis coordinates of the two points;

[0157] Differentiate the curve in the region, take a single bin as the smallest structural unit, and obtain the starting and ending coordinates of each bin [X a , Y a ]、[X b , Y b ];

[0158] Substituting the X-axis coordinates of the starting point and the end point into the above linear equation, we can get the X-axis and Y-axis coordinates of the two intersection points. Since this area can be regarded as having only one peak, we can calculate this area according to the following definite integral formula ( Fig.10 The area of ​​the green area is S MG :

[0159] Where: S MG represents the area under the curve of the glycosylated M protein peak, is the symbol of the definite integral, representing the integral from a to b, while f(x) is the integrand, representing the shape of the curve.

[0160] As above, the starting point and end point of the total light chain region of immunoglobulin were selected, and the region was calculated according to the above method ( Fig.10 The area of ​​the red area is S LC :

[0161] Based on the calculated peak area under the curve of the glycosylated M protein peak S MG The peak area under the curve S LC , the relative abundance M% of glycosylated M protein was obtained according to the following formula:

[0162] Relative abundance of M proteins based on glycosylation modification G %, combined with the quantitative results of serum immunoglobulin, the absolute content of glycosylated M protein was calculated. WG ,Right now:

[0163] M WG (mg / L)=TotalIg×M%=29.56(g / L)×95.4%=28.21(g / L)

[0164] The above two specific examples further demonstrate that the method of the present invention can not only realize the absolute quantitative detection of M protein in the sample to be detected, but also realize the absolute quantitative detection of immunoglobulin light chain glycosylation.

[0165] So far, the technical solutions of the present invention have been described in conjunction with the accompanying drawings and preferred embodiments. However, it is easy for those skilled in the art to understand that the protection scope of the present invention is obviously not limited to these specific embodiments. Without departing from the principle of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will fall within the protection scope of the present invention.

Claims

1. A qualitative and absolute quantitative detection method for M protein, characterized in that: The method comprises: Obtaining a mass spectrum of the sample to be tested; the mass spectrum at least includes a total light chain region; Performing peak detection on the mass spectrum to determine whether an M protein peak exists in the total light chain region; For the mass spectrum with M protein peak, calculate the peak area under the curve S of M protein peak M The peak area under the curve S LC Combined with the quantitative results of serum total immunoglobulin or serum total light chain, the absolute content of M protein is obtained. W .

2. The method for qualitative and absolute quantitative detection of M protein according to claim 1, characterized in that: The absolute content of M protein is obtained by combining the quantitative results of serum total immunoglobulin or serum total light chain. W ,include: Based on the calculated peak area under the curve S of the M protein peak M The peak area under the curve S LC , the relative abundance of M protein was obtained as M%; Based on the relative abundance M% of M protein, combined with the quantitative results of serum total immunoglobulin or serum total light chain, the absolute content M of M protein was obtained. W .

3. The method for qualitative and absolute quantitative detection of M protein according to claim 2, characterized in that: The relative abundance M% of M protein was calculated according to the following formula: The absolute content of M protein W Calculated according to the following formula: M W =TotalIg×M% or M W =TotalIgLC×M% Where: TotalIg——serum total immunoglobulin quantitative results; TotalIgLC——serum total light chain quantitative results.

4. The method for qualitative and absolute quantitative detection of M protein according to claim 1, characterized in that: The mass spectrum also includes the light chain glycosylation region; The qualitative and quantitative detection method further comprises: performing glycosylation detection on the light chain glycosylation region to obtain a glycosylation detection result.

5. The method for qualitative and absolute quantitative detection of M protein according to claim 4, characterized in that: The performing glycosylation detection on the light chain glycosylation region to obtain the glycosylation detection result comprises: Performing peak detection on the mass spectrum to determine whether there is a glycosylated M protein peak in the light chain glycosylation region; For the mass spectrum of the glycosylated M protein peak, calculate the peak area under the curve S of the glycosylated M protein peak. MG The peak area under the curve S LC Combined with the quantitative results of serum total immunoglobulin or serum total light chain, the absolute content of glycosylated M protein was obtained. WG .

6. The method for qualitative and absolute quantitative detection of M protein according to claim 5, characterized in that: The absolute content M of glycosylated M protein is obtained by combining the quantitative results of serum total immunoglobulin or serum total light chain. WG ,include: Based on the calculated peak area under the curve of the glycosylated M protein peak S MG The peak area under the curve S LC , and the relative abundance of glycosylated M protein was obtained. G %; Relative abundance of M proteins based on glycosylation modification G %, combined with the quantitative results of serum total immunoglobulin or serum total light chain, the absolute content of glycosylated M protein was obtained. WG .

7. The method for qualitative and absolute quantitative detection of M protein according to claim 6, characterized in that: The relative abundance of glycosylated M proteins G % is calculated according to the following formula: The absolute content of glycosylated M protein WG Calculated according to the following formula: M WG =TotalIg×M G % or M WG =TotalIgLC×M G % Where: TotalIg——serum total immunoglobulin quantitative results; TotalIgLC——serum total light chain quantitative results.

8. The method for qualitative and absolute quantitative detection of M protein according to any one of claims 5 to 7, characterized in that: The peak area under the curve of the M protein peak is S M , the peak area under the curve of the total light chain region S LC and the peak area under the curve of the glycosylated M protein peak S MG The following method is used to obtain: The starting point and the end point of each peak are selected respectively, and the area under the curve of each peak is definite integrally performed by the oblique cutting method. The definite integral result of each peak is the peak area under the curve of each peak.

9. The method for qualitative and absolute quantitative detection of M protein according to claim 8, characterized in that: The method of performing definite integration of the area under the curve of each peak by using the oblique cutting method includes: After selecting the starting point and end point of the peak, establish the linear equation y=ax+b using the X-axis and Y-axis coordinates of the two points; Differentiate the curve in the peak region, take a single bin as the smallest structural unit, and obtain the starting and ending coordinates of each bin [X a , Y a ]、[X b , Y b ]; Substitute the X-axis coordinates of the starting point and the end point into the above linear equation to obtain the X-axis and Y-axis coordinates of the two intersection points, and calculate the peak area under the curve of the peak according to the following definite integral formula: Where: S represents the peak area under the curve, is the symbol of the definite integral, representing the integral from a to b, while f(x) is the integrand, representing the shape of the curve.

10. An electronic device comprising a processor and a storage device, wherein the storage device is suitable for storing a plurality of program codes, characterized in that: The program code is suitable for being loaded and run by the processor to execute the qualitative and absolute quantitative detection method of the M protein according to any one of claims 1-9.

11. A computer-readable storage medium storing a plurality of program codes, characterized in that: The program code is suitable for being loaded and run by a processor to execute the qualitative and absolute quantitative detection method of the M protein according to any one of claims 1-9.

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