Method for evaluating function of organ for transplantation, program for evaluating function of organ for transplantation, and apparatus for evaluating function of organ for transplantation

Abstract

A method for evaluating the function of an organ for transplantation, which is a method for evaluating the function of an organ for transplantation removed from a living body, the method for evaluating the function of the organ for transplantation comprising the following steps: preparing data representing the change over time in the content of a plurality of marker substances caused by perfusion; at a first timing during reperfusion of the organ for transplantation, collecting a first tissue sample from the organ for transplantation; at a second timing during reperfusion that is later than the first timing, collecting a second tissue sample from the organ for transplantation; measuring the content of the plurality of marker substances in the first tissue sample; measuring the content of the plurality of marker substances in the second tissue sample; separately obtaining, for each of the plurality of marker substances, the change in the content at the second timing relative to the content at the first timing; and using the data and the obtained change in content to obtain an index related to the evaluation of the function of the organ for transplantation.

Description

Technical Field

[0001] The present invention relates to a method for evaluating the function of an organ for transplantation, a program for evaluating the function of an organ for transplantation, and a device for evaluating the function of an organ for transplantation. Background Art

[0002] As a technique for solving the chronic shortage of organs in transplantation medicine, a maintenance method for long-term preservation of an organ required for transplantation in a state where its function is still maintained is disclosed in Japanese Unexamined Patent Application Publication No. 2018-154617 (Patent Document 1). In Patent Document 1, by perfusing a perfusion solution containing an oxygen carrier and a blood coagulation inhibitor into an organ after cardiac arrest, it is possible to suppress tissue damage caused by warm ischemia and restore the organ to a state close to before cardiac arrest.

[0003] Prior Art Documents

[0004] Patent Documents

[0005] Patent Document 1: Japanese Unexamined Patent Application Publication No. 2018-154617 Summary of the Invention

[0006] Problems to be Solved by the Invention

[0007] In conventional organ transplantation, it is mainly judged whether an organ for transplantation is in a transplantable state based on the experience (tacit knowledge) of transplant surgeons and rapid pathological tissue diagnosis. If an organ that is judged to be transplantable according to the tacit knowledge of transplant surgeons but actually cannot function is transplanted, there is a possibility of falling into primary non-function (PNF). In particular, after transplanting the heart, lungs, and liver, which are called vital organs, if re-transplantation is not performed as soon as possible, it may lead to the death of the patient.

[0008] Thus, in the existing method, there is no objective judgment criterion for judging the potential function or the degree of irreversible damage of an organ, so it is impossible to accurately judge organ adaptability before transplantation, and this judgment is left to experienced transplant surgeons. Therefore, even for an organ removed after cardiac arrest whose function has been restored by the technique described in Patent Document 1 above, considering PNF, it may ultimately be judged as non-transplantable, which may hinder the solution to the shortage of donors. In addition, even if transplantation is performed, due to PNF, graft loss occurs, and there is always a risk of losing the patient.

[0009] The present invention has been completed to solve such problems, and an object thereof is to provide an index for objectively evaluating the feasibility of transplanting an organ for transplantation.

[0010] Solution for solving problems

[0011] The method for evaluating the function of a transplant organ according to the first aspect of the present invention is a method for evaluating the function of a transplant organ removed from a living body, and the method for evaluating the function of the transplant organ includes the following steps: preparing data representing the change over time of the contents of a plurality of marker substances caused by perfusion; at a first timing during reperfusion of the transplant organ, collecting a first tissue sample from the transplant organ; at a second timing after the first timing during reperfusion, collecting a second tissue sample from the transplant organ; measuring the contents of the plurality of marker substances in the first tissue sample; measuring the contents of the plurality of marker substances in the second tissue sample; respectively calculating the change in the content at the second timing relative to the content at the first timing for the plurality of marker substances; and using the data and the calculated change in the content to calculate an index related to the evaluation of the function of the transplant organ.

[0012] Effect of the invention

[0013] According to the present invention, an index for objectively evaluating the feasibility of transplanting a transplant organ can be provided. Description of the drawings

[0014] Figure 1 It is a diagram for explaining the process from the removal of the liver to reperfusion and the timing of obtaining tissue samples.

[0015] Figure 2 It is a diagram schematically showing a structural example of a perfusion circuit.

[0016] Figure 3 It is a schematic structural diagram of a mass spectrometry device and an evaluation device.

[0017] Figure 4 It is a diagram for explaining the evaluation criteria in the first evaluation.

[0018] Figure 5 It is a diagram for explaining the evaluation criteria in the second evaluation.

[0019] Figure 6 It is a diagram for explaining the evaluation criteria in the second evaluation.

[0020] Figure 7 It is a flowchart for explaining the method for evaluating the function of a liver graft according to the present embodiment.

[0021] Figure 8 It is for explaining Figure 7 The flowchart of the process of the first evaluation process shown in step S100 of

[0022] Figure 9 It is for explaining Figure 7Flowchart of the first modification example of the first evaluation process shown in step S100.

[0023] Figure 10 It is used to illustrate Figure 7 Flowchart of the second modification example of the first evaluation process shown in step S100.

[0024] Figure 11 It is used to illustrate Figure 7 Flowchart of the process of the second evaluation process shown in step S200. Detailed implementation mode

[0025] Next, the implementation mode of the present invention will be described in detail with reference to the accompanying drawings. In addition, the same or corresponding parts in the drawings are labeled with the same reference numerals, and the description thereof will not be repeated in principle.

[0026] [Outline of the method for evaluating the function of the organ for transplantation]

[0027] The method for evaluating the function of the organ for transplantation according to the present embodiment is outlined as follows: By performing mass spectrometry on the organ for transplantation, quantitative data related to a pre-specified marker substance is obtained, and by evaluating the obtained quantitative data according to a pre-set evaluation criterion, it is determined whether the organ for transplantation is in a transplantable state.

[0028] Next, first, the evaluation criterion used in the function evaluation method according to the present embodiment will be described. Then, the function evaluation method using this evaluation criterion will be described.

[0029] In addition, in the description of the present application, a mouse is used as the mammal that becomes the provider (donor) of the organ. In addition, the organ for transplantation is set as the liver. However, the mammal can be appropriately selected according to the recipient who is the object of the organ to be transplanted. Besides mice, for example, humans, pigs, cows, monkeys, dogs, cats, etc. can also be applied. This is because metabolomics analysis is used to obtain quantitative data of the labeling substance. In omics analysis, metabolomics analysis targets low-molecular-weight metabolites, but it is already known that there are no species differences in low-molecular-weight metabolites, and there are also almost common pathways in metabolic pathways such as the glycolysis system among almost all organisms, making it easy to extrapolate the results of animal experiments such as mice to the research of other species such as humans (for example, refer to Aono, R., et al. A pentose bisphosphate pathway for nucleoside degradation in Archaea. Nature Chemical Biology, 11(5), 355 - 360 (2015) and Yoshida, et al., "Diagnosis of digestive organ cancer by metabolome analysis - Search for pancreatic cancer biomarkers by metabolomics -", Journal of the Japanese Society of Clinical Laboratory Medicine, 63(4): 450 - 456). In addition, for organs, besides applying the liver, for example, the heart, kidney, lung, pancreas, stomach, small intestine, large intestine, testis, ovary, eyeball, etc. can also be applied.

[0030] (1) Regarding the liver function evaluation criteria

[0031] The inventors of the present application perfused three livers with different liver function states under common conditions in order to establish the evaluation criteria for the function of the liver for transplantation (hereinafter, also referred to as liver graft), and used mass spectrometry to measure the content of metabolites contained in each liver. In the measurement, in order to know how the content of metabolites changes during the process from liver removal to reperfusion, tissue samples were collected at multiple time points and mass spectrometry was performed.

[0032] Figure 1 It is a figure for explaining the processing process from liver removal to reperfusion and the sampling timing of tissue samples.

[0033] (1 - 1) Collection of tissue samples

[0034] For the test samples, livers removed from Wistar rats were used. In Figure 1 the example, sample A is a normal liver (Normal liver) removed from the body of a Wistar rat.

[0035] Specimen B is a donation after circulatory death (DCD) liver. Specimen B was obtained by making a warm ischemia model by stopping the heartbeat of a Wistar rat and leaving it for 10 minutes, and then removing the liver from the made warm ischemia model.

[0036] Specimen C is a donation after circulatory death (DCD) liver. Specimen C was obtained by making a warm ischemia model mouse by stopping the heartbeat of a Wistar rat and leaving it for 30 minutes, and then removing the liver from the made warm ischemia model mouse. In addition, five of each of Specimen A, Specimen B, and Specimen C were prepared.

[0037] During the liver removal process, a cannula for inflowing perfusion fluid was inserted into the portal vein of the liver, a cannula for outflowing perfusion fluid was inserted into the vein of the liver, and a cannula for outflowing bile was inserted into the bile duct. With these cannulas fixed to the liver, the liver was removed from the Wistar rat and the removed liver was placed in a storage container.

[0038] Here, the time from the heartbeat stop to the liver removal of Specimen B and Specimen C is different. This time is the "warm ischemia" time when the blood flow to the liver stops. In the liver in the warm ischemia state, cell swelling damage or waste accumulation caused by the depletion of ATP (adenosine triphosphate) occurs. Therefore, when the transplantation is completed and the blood flow to the liver is restored, the waste is rapidly metabolized by the oxidized perfusion fluid, resulting in a large amount of reactive oxygen species, and as a result, there are cases where liver damage is caused. Thus, in previous liver transplants, if the warm ischemia state lasts for several minutes, it is judged as non-transplantable. This judgment of transplantability is mainly based on the experience of transplant surgeons and histological opinions, and usually, a liver with a warm ischemia state lasting for 10 minutes is judged as transplantable. On the other hand, a liver with a warm ischemia state lasting for 30 minutes is judged as non-transplantable.

[0039] In the following description, the donation after circulatory death liver with a warm ischemia state lasting for 10 minutes is also referred to as "Mild DCD". The donation after circulatory death liver with a warm ischemia state lasting for 30 minutes is also referred to as "Severe DCD". In this embodiment, Specimen A (normal liver) and Specimen B (Mild DCD) are equivalent to livers with normal functions. On the other hand, Specimen C (Severe DCD) is equivalent to a liver with poor function.

[0040] Next, intravascular cleaning (rinsing) of the livers of each of Specimens A to C was performed. Normal saline was used for the cleaning. The normal saline was made to flow in through the cannula for inflowing perfusion fluid and flow out through the cannula for outflowing perfusion fluid. The outflowing normal saline was not circulated back into the cannula for inflowing perfusion fluid but was collected.

[0041] Next, after flowing UW solution (University of Wisconsin solution) to the washed liver and replacing the blood with UW solution, the liver was cold-preserved for 4 hours while immersed in UW solution. This cold preservation was carried out assuming the process of transporting the liver graft removed from the donor to the recipient at the actual medical site. The cold preservation time was set to 4 hours by estimating the maximum time required for transportation. This 4-hour time was obtained considering the case of using liver grafts generated from a distance.

[0042] After the cold preservation ended, the temperature of the liver was restored to the body temperature level of Wistar rats (about 37 °C) by rewarming the liver. Rewarming was performed for 10 minutes.

[0043] Next, reperfusion of the liver was carried out while maintaining the temperature of the liver at 37 °C. For the perfusion fluid, Krebs buffer was used. Figure 2 is a diagram schematically showing a structural example of the perfusion circuit. Refer to Figure 2 , the perfusion circuit has a storage container 10, perfusion fluid reservoirs 50, 60, a perfusion fluid inflow path 20, a perfusion fluid outflow path 30, a gas exchange mechanism 70, and a pump 22.

[0044] In the storage container 10, the liver 1 as a specimen is accommodated. The perfusion fluid reservoirs 50, 60 are containers for storing the perfusion fluid. A temperature mechanism (not shown) is connected to the perfusion fluid reservoirs 50, 60. The temperature mechanism is configured to keep the perfusion fluid stored in the perfusion fluid reservoirs 50, 60 at a fixed temperature (about 37 °C).

[0045] The perfusion fluid inflow path 20 is connected to a perfusion fluid inflow cannula 12 provided in the storage container 10. The pump 22 is inserted in the perfusion fluid inflow path 20. The perfusion fluid outflow path 30 is connected to a perfusion fluid outflow cannula 14 provided in the container 10.

[0046] The perfusion fluid inflow path 20 uses the pump 22 to supply the perfusion fluid from the perfusion fluid reservoir 50 to the liver 1 via the perfusion fluid inflow cannula 12. At this time, the pump 22 is controlled by a control unit (not shown) so that the pressure of the perfusion fluid is 3 mmHg to 8 mmHg.

[0047] The perfusion fluid flowing out from the liver 1 is recovered into the perfusion fluid reservoir 60 via the perfusion fluid outflow cannula 14 and the perfusion fluid outflow path 30. The gas exchange mechanism 70 is configured to: after dissolving gas by supplying gas such as oxygen to the perfusion fluid stored in the perfusion fluid reservoir 60, return the perfusion fluid to the perfusion fluid reservoir 50.

[0048] In addition, inFigure 2 Figure 2 shows an example of the structure of a circulating perfusion circuit that circulates the perfusion fluid, but it may also be configured to recover the used perfusion fluid without circulating it. During reperfusion, bile output from the bile duct of the liver 1 is collected into the container 80 via the bile drainage cannula 40.

[0049] During the series of steps described above, tissue slices are cut from the liver 1 for each specimen, and thus tissue samples S are collected. Figure 1 Figure 1 shows the timings T1 to T4 for collecting the tissue samples.

[0050] The timing T1 is set to the timing after liver washing and before cold preservation. The timing T2 is set to the timing immediately after cold preservation. That is, the timings T1 and T2 are set before and after cold preservation, respectively.

[0051] The timing T3 is set to the early stage of reperfusion. The early stage of reperfusion is the period when liver function is recovering. Figure 1 In the example of Figure 1 , the timing T3 is set to the timing 15 minutes after the start of reperfusion.

[0052] The timing T4 is set to the late stage of reperfusion. The late stage of reperfusion is the period when the recovery of liver function reaches its peak. Figure 1 In the example of Figure 1 , the timing T4 is set to the timing 60 minutes after the start of reperfusion. That is, the timings T3 and T4 are set to timings at which the states of liver function during reperfusion are different from each other.

[0053] (1-2) Mass spectrometry analysis of tissue samples

[0054] Next, mass spectrometry was used to screen the tissue samples of specimens A to C collected at the respective timings T1 to T4 described above. Liquid chromatography-mass spectrometry (LC / MS) was used in the mass spectrometry analysis.

[0055] Specifically, 500 μL of an internal standard solution was added to the tissue sample (about 50 mg), and homogenization was performed using a disposable homogenizer (BioMasher) (Nippi Inc.). Next, 250 μL of water was added to the homogenate and stirred, and further 500 μL of chloroform was added and stirred. After centrifugation (15,000 rpm, 4 °C, 5 minutes), 500 μL of the upper layer was extracted. Furthermore, the extract was dried using a centrifugal evaporator, and the residue was redissolved with 50 μL of water to obtain a specimen for measurement.

[0056] LC / MS analysis was performed using LCMS-8060 (Shimadzu Corporation). As the measurement mode for the LC / MS analysis, multiple reaction monitoring (MRM) and scan analysis were used.

[0057] Figure 3 This is a schematic structural diagram of the mass spectrometry device 100 and the evaluation device 120. Refer to Figure 3 , the mass spectrometry device 100 includes a liquid chromatography-mass spectrometry (LC / MS) unit 102, a data processing unit 104, and a control unit 106.

[0058] The LC / MS unit 102 includes a mass spectrometry unit and a liquid chromatograph equipped with a chromatographic column (not shown). The sample supplied to the chromatographic column is separated into each sample component during the process of passing through the chromatographic column, and is sequentially introduced into the mass spectrometry unit in a vacuum state for mass spectrometry. Thus, different spectra are obtained according to the retention time.

[0059] The mass spectrometry unit, for example, includes an ionization chamber, an ion trap, and a TOFMS (time-of-flight mass spectrometer). In the ionization chamber, the sample components separated by the liquid chromatograph are ionized using an ionization method such as ESI (electrospray ionization). The ionization method of the sample components is not limited to ESI, and various methods such as APCI (atmospheric pressure chemical ionization) can also be used.

[0060] The ion trap is, for example, a three-dimensional quadrupole type, capable of capturing the ions obtained in the ionization chamber, and selectively retaining a part of the captured ions in the ion trap, and breaking the ions by CID (collision-induced dissociation). The broken ions are supplied from the ion trap to the TOFMS.

[0061] In the TOFMS, the ions accelerated by the electric field formed in the flight space are separated in time according to the mass-to-charge ratio during the flight in the flight space, and are sequentially detected by an ion detector. The detection signal of the ion detector is input to the data processing unit 104 and converted into digital data, and then various data processes such as the production of mass spectra, mass chromatograms, and total chromatograms are performed.

[0062] The control unit 106 controls the operation of the LC / MS unit 102. In addition, the functions of the data processing unit 104 and the control unit 106 can be specifically realized by a personal computer equipped with a prescribed control / processing software.

[0063] In addition, in the present embodiment, the structure in which a liquid chromatography-mass spectrometry instrument is used as the mass spectrometry device 100 has been described, but a mass spectrometry device (PESI ionization mass spectrometry device) using a PESI ion source based on the probe electrospray ionization (PESI) method can also be used.

[0064] The control unit 106 transmits the data produced by the data processing unit 104 to the evaluation device 120. The evaluation device 120 is communicatively connected to the mass spectrometry device 100. The communication between the mass spectrometry device 100 and the evaluation device 120 can be achieved either through wireless communication or through wired communication.

[0065] The evaluation device 120 includes a CPU (Central Processing Unit) 122 as an arithmetic unit, a storage unit 124, a display unit 126, and an input unit 128 as main components. For the evaluation device 120, for example, a personal computer or the like can be used.

[0066] The CPU 122 reads and executes the program stored in the storage unit 124, thereby controlling the operations of the respective parts of the evaluation device 120. Specifically, the CPU 122 realizes the functional evaluation of the transplanted liver described later by executing this program. In addition, in Figure 3 the example, the structure in which the CPU 122 is one is illustrated, but the evaluation device 120 can also be configured to have a plurality of CPUs.

[0067] The storage unit 124 is implemented by a non-volatile memory such as a RAM (random access memory), a ROM (read only memory), and a flash memory. The storage unit 124 is used to store the program executed by the CPU 122, or the data used by the CPU 122, etc. This program can also be stored in a non-transitory computer-readable medium.

[0068] The display unit 126 and the input unit 128 are connected to the CPU 122. The display unit 126 is composed of a liquid crystal panel or the like capable of displaying images. The input unit 128 accepts the operation input by the user to the evaluation device 120. Typically, the input unit 128 is composed of a touch panel, a keyboard, a mouse, etc.

[0069] After the evaluation device 120 obtains the mass spectrometry data of the tissue samples at each timing T1 to T4 for each of the specimens A to C, it performs a quantitative analysis of the metabolites contained in the specimens based on the obtained mass spectrometry data. The quantitative data obtained at this time is used to set the evaluation criteria for the functional evaluation of the liver graft.

[0070] (1-3) Setting of evaluation criteria

[0071] The method for evaluating liver function according to this embodiment includes evaluations in two stages. The first evaluation is an evaluation performed using the quantitative data obtained before reperfusion, and the first evaluation is used to evaluate whether the function of the liver graft is good. The second evaluation is an evaluation performed using the quantitative data obtained during reperfusion, and the second evaluation is used to evaluate whether the liver graft whose function has been maintained or restored by reperfusion can be transplanted. In addition, since the first evaluation is a preliminary evaluation for the final second evaluation, it can also be omitted.

[0072] (i) Evaluation criteria in the first evaluation

[0073] In the first evaluation, as the evaluation criteria, a marker substance for evaluating liver function and a threshold value for determining whether liver function is good are used. Therefore, the marker substance is identified based on the quantitative data of the above three specimens A to C, and a threshold value is set for each marker substance.

[0074] Specifically, from the viewpoint that a functionally normal liver graft shows a high value and a functionally poor liver graft shows a low value, candidate marker substances were identified based on the quantitative data of specimens A to C collected at each timing T1 and T2.

[0075] In the quantitative data at timing T1 before cold preservation, as metabolites in which specimen A (normal liver) and specimen B (liver after mild cardiac arrest) show high values and specimen C (liver after severe cardiac arrest) shows a low value, two metabolites were identified as candidate marker substances. These two metabolites are uridine and adenylosuccinic acid.

[0076] On the other hand, in the quantitative data at timing T2 after cold preservation, as a metabolite in which specimen A (normal liver) and specimen B (liver after mild cardiac arrest) show high values and specimen C (liver after severe cardiac arrest) shows a low value, one metabolite was identified as a candidate marker substance. This metabolite is uridine.

[0077] In Figure 4 shows the content of the marker substance in the quantitative data at timing T1 and the content of the marker substance in the quantitative data at timing T2. Figure 4 (A) of Figure 4 is a graph showing the content of uridine at timing T1 of each specimen A to C,

[0078] According to Figure 4 In the graph of (A), at time T1, the content of uridine decreases in the order of normal liver, liver after mild cardiac arrest, and liver after severe cardiac arrest. Therefore, a threshold U1 for determining whether liver function is good is set between the normal liver and the liver after mild cardiac arrest and the liver after severe cardiac arrest. Specifically, the average value of the average of the uridine contents of the normal liver and the liver after mild cardiac arrest and the average of the uridine content of the liver after severe cardiac arrest is set as the threshold U1.

[0079] In addition, as Figure 4 shown in the graph of (B), at time T1, the content of adenylosuccinic acid decreases in the order of normal liver, liver after mild cardiac arrest, and liver after severe cardiac arrest. Therefore, a threshold A1 for determining whether liver function is good is set between the normal liver and the liver after mild cardiac arrest and the liver after severe cardiac arrest. Specifically, the average value of the average of the adenylosuccinic acid contents of the normal liver and the liver after mild cardiac arrest and the average of the adenylosuccinic acid content of the liver after severe cardiac arrest is set as the threshold A1.

[0080] On the other hand, as Figure 4 shown in the graph of (C), at time T2, the content of uridine decreases in the order of normal liver, liver after mild cardiac arrest, and liver after severe cardiac arrest. Therefore, a threshold U2 for determining whether liver function is good is set between the normal liver and the liver after mild cardiac arrest and the liver after severe cardiac arrest. Specifically, the average value of the average of the uridine contents of the normal liver and the liver after mild cardiac arrest and the average of the uridine content of the liver after severe cardiac arrest is set as the threshold U2.

[0081] (ii) Evaluation criteria in the second evaluation

[0082] In the second evaluation, as evaluation criteria, a marker substance for evaluating the maintenance and recovery of liver function by reperfusion and a threshold for determining transplantability are used. Therefore, the marker substance is identified based on the quantitative data of the above three specimens A to C, and a threshold is set for each marker substance.

[0083] Specifically, from the perspective of the change in content during reperfusion, marker substance candidates were identified based on the quantitative data of specimens A to C collected at each timing T3 and T4. As metabolites whose content changed between timing T3 and timing T4, ten metabolites were identified as marker substance candidates. These ten metabolites are Sedoheptulose 7 - phosphate, Adenosine triphosphate, Glucose - 6 - phosphate, Succinyl coenzyme A, Dimethylglycine, Choline, 2 - Aminobutyric acid, Uric acid, Pyruvic acid, and Inosine.

[0084] The Figure 5 shows the content of the marker substance in the quantitative data at timing T3 and the content of the marker substance in the quantitative data at timing T4. Figure 5 (A) to Figure 5 (J) of

[0085] In each figure, A(T3) is the content of the marker substance at timing T3 of specimen A (normal liver), and A(T4) is the content of the marker substance at timing T4 of specimen A (normal liver). B(T3) is the content of the marker substance at timing T3 of specimen B (liver after mild cardiac arrest), and B(T4) is the content of the marker substance at timing T4 of specimen B (liver after mild cardiac arrest). C(T3) is the content of the marker substance at timing T3 of specimen C (liver after severe cardiac arrest), and C(T4) is the content of the marker substance at timing T4 of specimen C (liver after severe cardiac arrest). The vertical axis of each graph corresponds to the value obtained by dividing the peak area ratio of the mass spectrum by the protein amount (peak area ratio of mass spectrum / protein amount).

[0086] As Figure 5 (A) shows, the content of Sedoheptulose 7 - phosphate increases in normal liver and liver after mild cardiac arrest and decreases in liver after severe cardiac arrest. As Figure 5 (E) of Figure 5 (F) of Figure 5 (G) of Figure 5 (H) of Figure 5 (I) of Figure 5 (J) shows, the same trend as Sedoheptulose 7 - phosphate was also found for the contents of Dimethylglycine, Choline, 2 - Aminobutyric acid, Uric acid, Pyruvic acid, and Inosine.

[0087] In contrast, as shown in (B) of Figure 5 , the content of adenosine triphosphate decreases in normal liver, increases in liver after mild cardiac arrest, and decreases in liver after severe cardiac arrest. Additionally, as shown in (C) of Figure 5 and Figure 5 (D), the contents of glucose-6-phosphate and succinyl coenzyme A increase in normal liver, liver after mild cardiac arrest, and liver after severe cardiac arrest.

[0088] In Figure 6 , the change trends of the contents from timing T3 to timing T4 are collectively shown for the ten marker substances shown in Figure 5 . Figure 6 is a table showing the change trends of the contents in a total of five samples for each of the samples A to C in fractions. In this table, for each marker substance, the fraction for the case where the content increases from timing T3 to timing T4 is set to "1", and the fraction for the case where the content decreases is set to "0".

[0089] In addition, it is also possible to determine the increase / decrease of the content based on the magnitude of the content between timing T3 and T4. In this case, when the content at timing T4 is greater than the content at timing T3, the fraction is set to "1", and when the content at timing T4 is less than the content at timing T3, the fraction is set to "0".

[0090] Alternatively, it is also possible to determine the increase / decrease of the content based on the change rate of the content ratio between timing T3 and T4. In this case, the ratio of the content at timing T4 to the content at timing T3 is calculated. When the contents at timing T3 and T4 are equal, the ratio = 1. If the content at timing T4 is greater than the content at timing T3, the ratio > 1, and if the content at timing T4 is less than the content at timing T3, the ratio < 1.

[0091] A first threshold greater than 1 and a second threshold less than 1 are preset for the above ratio, and the calculated ratio is compared with the first threshold and the second threshold. When the calculated ratio is greater than the first threshold, it is determined that the content has increased, and the fraction is set to "1". When the calculated ratio is less than the second threshold, it is determined that the content has decreased, and the fraction is set to "0".

[0092] Refer to Figure 6, for example, in the case of sedoheptulose 7-phosphate, for specimen A (normal liver), the scores of two of the five specimens A1 - A5, namely A1 and A3, represent "1", and the scores of the remaining three specimens A2, A4, and A5 represent "0". In contrast, for specimen B (liver after mild cardiac arrest), the scores of all five specimens B1 - B5 represent "1", and for specimen C (liver after severe cardiac arrest), the scores of all five specimens C1 - C5 represent "0".

[0093] In the cases of glucose-6-phosphate, dimethylglycine, choline, 2-aminobutyric acid, and uric acid, for specimen A (normal liver) and specimen B (liver after mild cardiac arrest), the scores of all five specimens represent "1", and for specimen C (liver after severe cardiac arrest), the scores of all five specimens C1 - C5 represent "0".

[0094] After calculating the scores for each marker substance, the sum value of the ten scores is calculated for each type of specimen. That is, the highest value of the total score is "10", and the lowest value is "0".

[0095] As Figure 6 shown, the total score distributions of specimen A (normal liver) and specimen B (liver after mild cardiac arrest) are values close to the highest value "10". In contrast, the total score distribution of specimen C (liver after severe cardiac arrest) is a value close to the lowest value "0".

[0096] According to Figure 6 the table, for nine of the ten marker substances, the change trends of the contents of the marker substances from timing T3 to timing T4 in specimen A (normal liver) and specimen B (liver after mild cardiac arrest) are consistent. As a result, the total scores of the normal liver and the liver after mild cardiac arrest are approximately the same.

[0097] In contrast, for nine of the ten marker substances, the change trends of the contents of the marker substances from timing T3 to timing T4 in specimen A (normal liver) and specimen C (liver after severe cardiac arrest) are different. As a result, the total scores of the normal liver and the liver after severe cardiac arrest are not approximately the same, but are significantly different values. In Figure 6 the table, compared with the normal liver, the total score of the liver after severe cardiac arrest is significantly reduced.

[0098] The inventors of the present application set a threshold for the total score based on Figure 6 the table to distinguish between the normal liver and the liver after mild cardiac arrest and the liver after severe cardiac arrest, and set this threshold as a reference value for determining whether the liver graft has recovered function through reperfusion or has not yet recovered function.

[0099] Specifically, the total score of the normal liver and the liver after mild cardiac arrest represents a range from "6" to "10". On the other hand, the total score of the liver after severe cardiac arrest represents "0" or "1". Therefore, the reference value is set to "2".

[0100] Thus, the total score can be used to determine whether the liver graft after reperfusion is in a transplantable state. Specifically, when the total score of the liver graft is higher than the reference value "2", it is determined that the liver graft is transplantable. In this case, it can be judged that the change trend of the content of the marker substance in the liver graft from time T3 to time T4 is consistent with that of the normal liver. Therefore, it can be judged that the function of the liver graft has been restored to a transplantable level through reperfusion.

[0101] On the other hand, when the total score of the liver graft is less than or equal to the threshold value "2", it is determined that the liver graft is not transplantable. In this case, it can be judged that the change trend of the content of the marker substance in the liver graft from time T3 to time T4 is different from that of the normal liver. Therefore, it can be judged that the function of the liver graft has not been restored to a transplantable level even through reperfusion.

[0102] In addition, in the second evaluation, by adopting a structure in which the total score of the scores of ten marker substances is used to determine transplantability, the deviation of the scores of each marker substance can be absorbed. In other words, even in the case of a normal liver, there are deviations in the increasing / decreasing trends of the contents among multiple samples. Therefore, when judging whether the change trend of the content is consistent with that of the normal liver in terms of each marker substance, misjudgment may occur. By comprehensively judging whether the change trend of the overall content of the marker substances is consistent using the total score of all the marker substances, such misjudgment can be prevented.

[0103] (2) Regarding the method for evaluating liver function

[0104] Next, a method for evaluating the function of a liver graft using the above evaluation criteria will be described.

[0105] Figure 7 is a flowchart for explaining the method for evaluating the function of the liver graft according to the present embodiment. In Figure 7 shows a flowchart for explaining the processing procedure from the removal of the liver graft to reperfusion ( Figure 7 left figure), a flowchart for explaining the processing procedure of the mass spectrometry device ( Figure 7 central figure), and a flowchart for explaining the processing procedure of the evaluation device ( Figure 7 right figure).

[0106] Refer to Figure 7, in step S10, the liver graft is removed from the donor. In step S20, a flushing process for cleaning the blood vessels in the removed liver graft is performed. During the cleaning, for example, normal saline can be used. The cleaned liver graft is immersed in UW solution.

[0107] In step S30, a tissue sample is collected from the liver graft. The collection of the tissue sample performed through step S30 corresponds to Figure 1 the timing T1 in

[0108] In step S40, a cold preservation process for the liver graft is performed. The time for cold preservation is not particularly limited, and the user can appropriately set it considering the transportation time of the liver graft from the donor to the recipient, etc. In addition, the preservation solution is not limited to UW solution, and can be appropriately selected by the user.

[0109] At the time point when the cold preservation process (step S40) ends, in step S50, a tissue sample is collected from the liver graft. The collection of the tissue sample performed through step S50 corresponds to Figure 1 the timing T2 in

[0110] In step S60, a rewarming process for the liver graft is performed. The temperature of the liver graft is restored to about 37°C through the rewarming process.

[0111] In step S70, under the state of maintaining the temperature of the liver graft at about 37°C, a reperfusion process for the liver graft is performed. For example, Figure 2 the perfusion circuit shown in

[0112] Figure 1 can be used to perform the reperfusion process. However, the perfusion fluid is not limited to Krebs buffer, and can be appropriately selected by the user. When the reperfusion starts, through step S80, a tissue sample is collected from the liver graft at a specified timing in the initial stage of reperfusion (for example, 15 minutes after the start of reperfusion). The collection of the tissue sample performed through step S80 corresponds to Figure 1 the timing T3 in

[0113] In the mass spectrometry device 100, the tissue sample collected in step S30 is subjected to mass spectrometry through step S31. The mass spectrometry data obtained through the mass spectrometry is transmitted to the evaluation device 120.

[0114] After that, in the mass spectrometry device 100, mass spectrometry analysis is performed on the tissue samples collected in steps S50, S80, and S90 through steps S51, S81, and S91 respectively. The mass spectrometry data obtained in each mass spectrometry analysis process is transmitted to the evaluation device 120.

[0115] In the evaluation device 120, an evaluation related to whether the liver graft is in a transplantable state is performed based on the mass spectrometry data transmitted from the mass spectrometry device 100.

[0116] Specifically, initially, the evaluation device 120 obtains the mass spectrometry data of the tissue sample collected at the timing T1 before cold preservation (S40) through step S32, and then obtains the mass spectrometry data of the tissue sample collected at the timing T2 after cold preservation (S40) through step S52. The evaluation device 120 performs the first evaluation process using these two mass spectrometry data through step S100.

[0117] Figure 8 is used to illustrate Figure 7 the process of the first evaluation process shown in step S100. Figure 8 The flowchart can be executed by the CPU 122 of the evaluation device 120.

[0118] Referring to Figure 8 CPU 122 detects the content M1(T1) of uridine as a marker substance based on the mass spectrometry data at timing T1 through step S101. Then, CPU 122 detects the content M1(T2) of uridine based on the mass spectrometry data at timing T2 through step S102. In steps S101 and S102, CPU 122 detects the content M1 of uridine by dividing the peak area ratio of the mass spectrum by the protein mass.

[0119] Next, CPU 122 compares the content M1(T1) of uridine with the threshold U1 through step S103. In Figure 4 the (A) of

[0120] When the content M1(T1) of uridine is less than or equal to the threshold U1 (\"No\" in S103), CPU 122 determines that the function of the liver graft is poor through step S106.

[0121] On the other hand, when the content M1(T1) is greater than the threshold U1 (\"Yes\" in S103), CPU 122 then compares the content M1(T2) of uridine with the threshold U2 through step S104. In Figure 4In (C), the threshold value U2 is a value set based on the uridine content of normal liver, mildly cardiac arrest liver, and severely cardiac arrest liver at timing T2.

[0122] When the content M1(T2) of uridine is below the threshold value U2 (No in S104), the CPU 122 determines that the function of the liver graft is poor through step S106. On the other hand, when the content M1(T2) of uridine is greater than the threshold value U2 (Yes in S104), the CPU 122 determines that the function of the liver graft is normal through step S105.

[0123] In addition, in Figure 8 the flowchart shown, the function of the liver graft is determined based on the content of uridine at timings T1 and T2, but it is also possible to determine the function of the liver graft based on the content of uridine and adenylosuccinic acid at timing T1 as shown in Figure 9 . Or, it is also possible to determine the function of the liver graft based on the content of uridine at timing T2 as shown in Figure 10 .

[0124] Figure 9 is a flowchart for explaining a first modification example of the first evaluation process shown in step S100 of Figure 7 .

[0125] Referring to Figure 9 , the CPU 122 detects the content M1(T1) of uridine as a marker substance based on the mass spectrometry data at timing T1 through step S101. Then, the CPU 122 detects the content M2(T1) of adenylosuccinic acid based on the mass spectrometry data at timing T1 through step S107.

[0126] Next, the CPU 122 compares the content M1(T1) of uridine with the threshold value U1 through step S103. When the content M1(T1) of uridine is below the threshold value U1 (No in S103), the CPU 122 determines that the function of the liver graft is poor through step S106.

[0127] On the other hand, when the content M1(T1) is greater than the threshold value U1 (Yes in S103), the CPU 122 then compares the content M2(T1) of adenylosuccinic acid with the threshold value A1 through step S108. In Figure 4 , the threshold value A1 is a value set based on the content of adenylosuccinic acid of normal liver, mildly cardiac arrest liver, and severely cardiac arrest liver at timing T1.

[0128] When the content M2(T1) of adenylosuccinic acid is below the threshold value A1 (No in S108), the CPU 122 determines through step S106 that the function of the liver graft is poor. On the other hand, when the content M2(T1) of adenylosuccinic acid is greater than the threshold value A1 (Yes in S108), the CPU 122 determines through step S105 that the function of the liver graft is normal.

[0129] Figure 10 is for explaining Figure 7 the second modification example of the first evaluation process shown in step S100.

[0130] Referring to Figure 10 , the CPU 122 detects the content M1(T2) of uridine as a marker substance according to the mass spectrometry data at timing T2 through step S102.

[0131] Next, the CPU 122 compares the content M1(T2) of uridine with the threshold value U2 through step S104. When the content M1(T2) of uridine is below the threshold value U2 (No in S104), the CPU 122 determines through step S106 that the function of the liver graft is poor. On the other hand, when the content M1(T2) is greater than the threshold value U2 (Yes in S104), the CPU 122 determines through step S105 that the function of the liver graft is normal.

[0132] Return to Figure 7 , the evaluation device 120 obtains the mass spectrometry data of the tissue sample collected at timing T3 in the initial stage of reperfusion through step S82, and then obtains the mass spectrometry data of the tissue sample collected at timing T4 in the later stage of reperfusion through step S92. The evaluation device 120 performs the second evaluation process through step S200 using these two mass spectrometry data.

[0133] Figure 11 is for explaining Figure 7 the process of the second evaluation process shown in step S200. Figure 11 The flowchart can be executed by the CPU 122 of the evaluation device 120.

[0134] Referring to Figure 11, the CPU 122 selects an object marker substance Mi (i is an integer from 1 to 10) from among ten marker substances through step S201. Next, the CPU 122 detects the content Xi(T3) of the metabolite of the object marker substance Mi based on the mass spectrometry data at timing T3 through step S202. The CPU 122 further detects the content Xi(T4) of the object marker substance Mi based on the mass spectrometry data at timing T4 through step S203. In steps S202 and S203, the CPU 122 detects the content Xi of the object marker substance by dividing the peak area ratio of the mass spectrometry by the protein mass.

[0135] Next, the CPU 122 calculates the change trend of the content Xi from timing T3 to timing T4 through step S204. In step S204, for example, the CPU 122 determines the change trend (increase / decrease) of the content Xi based on the magnitudes of Xi(T3) and Xi(T4). In this case, if Xi(T3) < Xi(T4), the CPU 122 determines that the content Xi has increased, and if Xi(T3) > Xi(T4), the CPU 122 determines that the content Xi has decreased.

[0136] Alternatively, the CPU 122 can determine the increase / decrease of the content Xi based on the change rate (= Xi(T4) / Xi(T3)) of Xi(T3) and Xi(T4). The CPU 122 calculates the ratio of the content Xi(T4) to the content Xi(T3). When Xi(T3) = Xi(T4), the ratio = 1. On the other hand, when Xi(T4) > Xi(T3), the ratio > 1, and when Xi(T4) < Xi(T3), the ratio < 1.

[0137] The CPU 122 compares the calculated change rate with a first threshold (the first threshold > 1), and when the change rate is greater than the first threshold, determines that the content Xi has increased. In addition, the CPU 122 compares the change rate with a second threshold (the second threshold < 1), and when the change rate is less than the second threshold, determines that the content Xi has decreased.

[0138] Next, the CPU 122 proceeds to step S205 and determines whether the change trend of the content Xi obtained in step S204 is consistent with the change trend of the content of the marker substance Mi in normal liver. The change trend of the content of the marker substance Mi in normal liver is based on Figure 5 the change trend of the content of the marker substance at timings T3 and T4 of the normal liver (specimen A) shown. The CPU 122 can calculate the change trend of the content of the marker substance Mi in normal liver using the same method as the method described in step S204.

[0139] In step S205, when the change trend of the content of the marker substance Mi in the liver graft is consistent with the change trend of the content of the marker substance Mi in the normal liver (being "Yes" in S205), the CPU 122 sets the score for the marker substance Mi to "1" through step S206. On the other hand, when the change trend of the content of the marker substance Mi in the liver graft is inconsistent with the change trend of the content of the marker substance Mi in the normal liver (being "No" in S205), the CPU 122 sets the score for the marker substance Mi to "0" through step S207.

[0140] In addition, as long as the scores in the case where the degree of consistency between the change trend of the content of the marker substance Mi in the liver graft and the change trend of the content of the marker substance Mi in the normal liver is large are different from the scores in the case where the degree of consistency is small, the value of the score is not limited to "1" and "0". It is also possible to obtain the absolute value of the change, set the score to "1" when the degree of consistency is large, set the score to "0" when the degree of consistency is small, and when the degree of consistency is between large and small, the score can also be set to "0.5".

[0141] Next, the CPU 122 determines through step S208 whether all ten marker substances are selected as the target marker substances. When not all marker substances are selected (being "No" in S208), the CPU 122 returns the process to step S201, selects the next marker substance M(i + 1) as the target marker substance, and executes the processes of steps S0202 to S207 again.

[0142] On the other hand, when all ten marker substances are selected as the target marker substances (being "Yes" in S208), the CPU 122 proceeds to step S209 and calculates the total score by adding up the scores of all marker substances.

[0143] The CPU 122 compares the total score calculated in step S209 with the reference value (= 2) through step S210. This reference value is based on Figure 6 the values of the total scores of the normal liver, the liver after mild cardiac arrest, and the liver after severe cardiac arrest shown.

[0144] When the total score is higher than the reference value (being "Yes" in S210), the CPU 122 determines through step S211 that the liver graft is in a transplantable state. On the other hand, when the total score is below the reference value (being "No" in S210), the CPU 122 determines through step S212 that the liver graft is in a non - transplantable state.

[0145] That is, the fraction or total fraction related to each marker substance functions as an index related to the functional evaluation of the liver graft.

[0146] Return to Figure 7 , the CPU 122 displays the evaluation results in the first evaluation process (S100) and the second evaluation process (S200) on the display unit 126 through step S300. A user such as a transplant surgeon can determine whether to transplant the liver graft into the recipient based on the evaluation results displayed on the display unit 126.

[0147] As described above, the method for evaluating the function of a transplant organ according to the present embodiment obtains quantitative data related to a pre-specified marker substance by performing mass spectrometry on the transplant organ, and evaluates the obtained quantitative data according to a pre-set evaluation criterion, thereby determining whether the transplant organ is in a transplantable state. Thus, it is possible to objectively determine the transplantability of a transplant organ that has been based on the experience of transplant surgeons and histological opinions in the past. In addition, since it is possible to determine transplantability before performing organ transplantation, the number of organs available for transplantation can be increased.

[0148] Moreover, according to the method for evaluating the function of a transplant organ according to the present embodiment, not only a brain-dead liver can be used for transplantation, but also the possibility that a liver after cardiac arrest that has recovered its function through reperfusion can be used for transplantation is increased, so it is possible to help solve the shortage of donor organs.

[0149] [Other Embodiments]

[0150] In the above embodiment, the degree of consistency between the change trend of the content of the marker substance Mi in the liver graft and the change trend of the content of the marker substance Mi in the normal liver was scored, and the total score of each marker substance was obtained, thereby performing the functional evaluation of the transplant organ. In other embodiments, scoring may not be performed, and the functional evaluation of the transplant organ may be performed by regression analysis. For example, a regression equation may be created by setting the change amount of the content of the marker substance Mi as the explanatory variable and the normality of the function of the transplant organ as the target variable.

[0151] [Mode]

[0152] Those skilled in the art can understand that the above-mentioned multiple exemplary embodiments are specific examples of the following modes.

[0153] (First item) A method for evaluating the function of a transplant organ involves a method for evaluating the function of a transplant organ removed from a living body. The method for evaluating the function of a transplant organ includes the following steps: preparing data representing the change over time in the content of various marker substances caused by perfusion; at a first timing during reperfusion of the transplant organ, collecting a first tissue sample from the transplant organ; at a second timing later than the first timing during reperfusion, collecting a second tissue sample from the transplant organ; measuring the content of various marker substances in the first tissue sample; measuring the content of various marker substances in the second tissue sample; respectively obtaining the change in the content at the second timing relative to the content at the first timing for various marker substances; and using the data and the obtained change in content to obtain an index related to the function evaluation of the transplant organ.

[0154] According to the function evaluation method described in the first item, by indexing the change in the content of each of the various marker substances during reperfusion, it is possible to determine whether the transplant organ is suitable for transplantation based on this index. Thus, it is possible to objectively judge whether the transplant organ is in a transplantable state before transplantation. In addition, the possibility that an organ after cardiac arrest whose function has been restored by reperfusion can also be used for transplantation is increased, so it can help solve the shortage of donor organs.

[0155] (Second item) In the method for evaluating the function of a transplant organ described in the first item, the step of obtaining the change includes the step of obtaining the change trend of the content. The step of obtaining the index includes the step of scoring the change trend of the content. The scoring step includes the following steps: the score when the change trend of the content in the transplant organ is made consistent with the change trend of the content in a normally functioning organ is higher than the score when the change trend of the content in the transplant organ is inconsistent with the change trend of the content in a normally functioning organ.

[0156] According to the function evaluation method described in the second item, by scoring the change trend of the content of each of the various marker substances during reperfusion based on the change trend of the content of each of the various marker substances in a normally functioning organ, it is possible to objectively determine whether transplantation is possible based on this score.

[0157] (Third item) In the method for evaluating the function of a transplant organ described in the first or second item, the step of measuring the content of various marker substances in the first tissue sample and the step of measuring the content of various marker substances in the second tissue sample each include the step of using mass spectrometry to measure the content of various marker substances.

[0158] According to the function evaluation method described in the third item, by performing mass spectrometry on the first tissue sample and the second tissue sample, it is possible to index the change in the content of each of the various marker substances during reperfusion.

[0159] (Item 4) In the method for evaluating the function of the organ for transplantation described in Items 1 to 3, the step of obtaining the change further includes the following steps: when the change rate of the content at the second timing relative to the content at the first timing is greater than the first threshold, it is determined that the content increases; when the change rate is less than the second threshold, it is determined that the content decreases. The first threshold is a value greater than 1, and the second threshold is a value less than 1.

[0160] According to the function evaluation method described in Item 4, it is possible to appropriately score the changes in the contents of various marker substances during reperfusion regardless of the deviation of the tissue sample. Thus, it is possible to determine whether transplantation is possible with high accuracy.

[0161] (Item 5) In the method for evaluating the function of the organ for transplantation described in Items 1 to 4, the organ for transplantation is the liver. The various marker substances include at least two marker substances selected from sedoheptulose 7-phosphate, adenosine triphosphate, glucose-6-phosphate, succinyl coenzyme A, dimethylglycine, choline, 2-aminobutyric acid, uric acid, pyruvic acid, and inosine.

[0162] According to the function evaluation method described in Item 5, by indexing the changes in the contents of various marker substances during reperfusion, it is possible to determine whether the liver graft is suitable for transplantation based on this index. Thus, it is possible to objectively judge whether the liver graft is in a transplantable state before transplantation. In addition, the possibility of using the liver after cardiac arrest whose function has been restored by reperfusion for transplantation is increased, so it is possible to help solve the shortage of donor organs.

[0163] (Item 6) The method for evaluating the function of the organ for transplantation according to any one of Items 1 to 5 further includes the following steps: cold-preserving the organ for transplantation during the period after removal from the donor and before reperfusion; collecting a third tissue sample from the organ for transplantation at a third timing before the start of cold preservation; collecting a fourth tissue sample from the organ for transplantation at a fourth timing after the end of cold preservation and before the start of reperfusion; measuring the content of the first marker substance in the third tissue sample; measuring the content of the first marker substance in the fourth tissue sample; and determining whether the function of the organ for transplantation is normal based on the content of the first marker substance at the third timing and the fourth timing.

[0164] According to the function evaluation method described in the sixth item, it is possible to determine whether the function of the organ for transplantation before reperfusion is good.

[0165] (Seventh item) The function evaluation method for the organ for transplantation according to the first to fifth items further includes the following steps: performing cold preservation on the organ for transplantation during the period after removal from the donor and before reperfusion; at a fourth timing after the end of cold preservation and before the start of perfusion, collecting a fourth tissue sample from the organ for transplantation; measuring the content of the first marker substance in the fourth tissue sample; and determining whether the function of the organ for transplantation is normal based on the content of the first marker substance at the fourth timing.

[0166] According to the function evaluation method described in the seventh item, it is possible to determine whether the function of the organ for transplantation before reperfusion is good.

[0167] (Eighth item) The function evaluation method for the organ for transplantation according to the first to fifth items further includes the following steps: performing cold preservation on the organ for transplantation during the period after removal from the donor and before reperfusion; at a third timing before the start of cold preservation, collecting a third tissue sample from the organ for transplantation; measuring the contents of the first marker substance and the second marker substance in the third tissue sample; and determining whether the function of the organ for transplantation is normal based on the contents of the first marker substance and the second marker substance at the third timing.

[0168] According to the function evaluation method described in the eighth item, it is possible to determine whether the function of the organ for transplantation before reperfusion is good.

[0169] (Ninth item) In the function evaluation method for the organ for transplantation described in the sixth or seventh item, the organ for transplantation is the liver, and the first marker substance is uridine.

[0170] According to the function evaluation method described in the ninth item, it is possible to determine whether the function of the liver graft before reperfusion is good.

[0171] (Tenth item) In the function evaluation method for the organ for transplantation described in the eighth item, the organ for transplantation is the liver. The first marker is uridine, and the second marker is adenylosuccinic acid.

[0172] According to the function evaluation method described in the tenth item, it is possible to determine whether the function of the liver graft before reperfusion is good.

[0173] (Item 11) The program for evaluating the function of a transplant organ described in Item 11 uses a computer having an arithmetic unit to evaluate the function of a transplant organ removed from a living body. The program causes the arithmetic unit to perform the following steps: preparing data representing the change over time in the contents of various marker substances caused by perfusion; at a first timing during reperfusion, collecting a first tissue sample from the transplant organ; at a second timing during reperfusion that is later than the first timing, collecting a second tissue sample from the transplant organ; measuring the contents of the various marker substances in the first tissue sample; measuring the contents of the various marker substances in the second tissue sample; separately obtaining the change in the content at the second timing relative to the content at the first timing for each of the various marker substances; and using the data and the obtained change in content to obtain an index related to the evaluation of the function of the transplant organ.

[0174] According to the program described in Item 11, by indexing the change in the content of each of the various marker substances during reperfusion, it is possible to determine whether the transplant organ is transplantable based on this index. Thus, it is possible to objectively judge whether the transplant organ is in a transplantable state before transplantation. In addition, the possibility that an organ after cardiac arrest whose function has been restored by reperfusion can also be used for transplantation is increased, so it is possible to help solve the shortage of donor organs.

[0175] (Item 12) The function evaluation device for a transplant organ described in Item 12 includes an arithmetic unit. The function evaluation device prepares data representing the change over time in the contents of various marker substances caused by perfusion. The arithmetic unit measures the contents of the various marker substances in a first tissue sample collected from the transplant organ at a first timing during reperfusion of the transplant organ. It measures the contents of the various marker substances in a second tissue sample collected from the transplant organ at a second timing during reperfusion that is later than the first timing. Separately obtains the change in the content at the second timing relative to the content at the first timing for each of the various marker substances, and uses the data and the obtained change in content to obtain an index related to the evaluation of the function of the transplant organ.

[0176] According to the function evaluation device described in Item 12, by indexing the change in the content of each of the various marker substances during reperfusion, it is possible to determine whether the transplant organ is transplantable based on this index. Thus, it is possible to objectively judge whether the transplant organ is in a transplantable state before transplantation. In addition, the possibility that an organ after cardiac arrest whose function has been restored by reperfusion can also be used for transplantation is increased, so it is possible to help solve the shortage of donor organs.

[0177] The embodiments disclosed herein should be considered illustrative in all respects and not restrictive. The scope of the present invention is shown not by the above description but by the claims, including all modifications within the meaning and scope equivalent to the claims.

[0178] Explanation of reference numerals

[0179] 1: Liver; 10: Preservation container; 12: Cannula for inflow of perfusion fluid; 14: Cannula for outflow of perfusion fluid; 20: Path for inflow of perfusion fluid; 22: Pump; 30: Path for outflow of perfusion fluid; 40: Cannula for outflow of bile; 50, 60: Perfusion fluid reservoir; 70: Gas exchange mechanism; 80: Container; 100: Mass spectrometry device; 102: LC / MS unit; 104: Data processing unit; 106: Control unit; 120: Evaluation device; 122: CPU; 124: Storage unit; 126: Display unit; 128: Input unit.

Claims

1. A method for evaluating the function of a transplant organ, which is a method for evaluating the function of a transplant organ removed from a living body, and the method for evaluating the function of the transplant organ includes the following steps: Prepare data representing the change over time in the content of a variety of marker substances caused by reperfusion; At a first timing during reperfusion of the transplant organ, collect a first tissue sample from the transplant organ; At a second timing during reperfusion that is later than the first timing, collect a second tissue sample from the transplant organ; Measure the content of the variety of marker substances in the first tissue sample; Measure the content of the variety of marker substances in the second tissue sample; For each of the variety of marker substances, calculate the change in the content at the second timing relative to the content at the first timing; and Use the data and the calculated change in the content to calculate an index related to the evaluation of the function of the transplant organ, wherein, The step of calculating the change includes a step of calculating the change trend of the content for each of the variety of marker substances, The step of calculating the index includes a step of scoring the change trends of the content of the variety of marker substances using the data, The step of performing the scoring includes the following steps: The score when the change trend of the content in the transplant organ is consistent with the change trend of the content in the functionally normal organ of the data is higher than the score when the change trend of the content in the transplant organ is inconsistent with the change trend of the content in the functionally normal organ of the data, The step of calculating the index further includes calculating the sum of the scores of each marker substance among the variety of marker substances as the index.

2. The method for evaluating the function of a transplant organ according to claim 1, wherein The step of measuring the content of the variety of marker substances in the first tissue sample and the step of measuring the content of the variety of marker substances in the second tissue sample each include a step of measuring the content of the variety of marker substances using mass spectrometry.

3. The method for evaluating the function of a transplant organ according to claim 1 or 2, wherein The step of calculating the change further includes the following steps: When the change rate of the content at the second timing relative to the content at the first timing is greater than a first threshold, it is determined that the content increases, and when the change rate is less than a second threshold, it is determined that the content decreases. The first threshold is a value greater than 1, and the second threshold is a value less than 1.

4. The method for evaluating the function of a transplant organ according to claim 1 or 2, wherein The transplant organ is the liver, The multiple marker substances include at least two marker substances selected from Sedoheptulose 7 - phosphate, Adenosine triphosphate, Glucose - 6 - phosphate, Succinyl coenzyme A, Dimethylglycine, Choline, 2 - Aminobutyric acid, Uric acid, Pyruvic acid, and Inosine.

5. The method for evaluating the function of a transplant organ according to claim 1 or 2, wherein the transplant organ is cryopreserved during the period after being removed from the donor and before the reperfusion. The method for evaluating the function of the transplant organ further includes the following steps: At a third timing before the start of the cryopreservation, a third tissue sample is collected from the transplant organ. At a fourth timing after the end of the cryopreservation and before the start of the reperfusion, a fourth tissue sample is collected from the transplant organ. The content of a first marker substance is measured by performing mass spectrometry on the third tissue sample. The content of the first marker substance is measured by performing mass spectrometry on the fourth tissue sample. And Based on the content of the first marker substance at the third timing and the fourth timing, it is determined whether the function of the transplant organ is normal.

6. The method for evaluating the function of a transplant organ according to claim 1 or 2, wherein the transplant organ is cryopreserved during the period after being removed from the donor and before the reperfusion. The method for evaluating the function of the transplant organ further includes the following steps: At a fourth timing after the end of the cryopreservation and before the start of the reperfusion, a fourth tissue sample is collected from the transplant organ. The content of a first marker substance is measured by performing mass spectrometry on the fourth tissue sample. And Based on the content of the first marker substance at the fourth timing, it is determined whether the function of the transplant organ is normal.

7. The method for evaluating the function of a transplant organ according to claim 1 or 2, wherein the transplant organ is cryopreserved during the period after being removed from the donor and before the reperfusion. The method for evaluating the function of the transplant organ further includes the following steps: At a third timing before the start of the cryopreservation, a third tissue sample is collected from the transplant organ. The contents of a first marker substance and a second marker substance are measured by performing mass spectrometry on the third tissue sample. And Based on the contents of the first marker substance and the second marker substance at the third timing, it is determined whether the function of the transplant organ is normal.

8. The method for evaluating the function of a transplant organ according to claim 5, wherein the transplant organ is the liver. The first marker substance is Uridine.

9. The method for evaluating the function of an organ for transplantation according to claim 7, characterized in that, the organ for transplantation is the liver, the first marker substance is uridine, the second marker substance is adenylosuccinic acid.

10. A computer-readable storage medium records a program for evaluating the function of an organ for transplantation removed from a living body using a computer having an arithmetic unit. The program causes the arithmetic unit to execute the following steps: Prepare data representing the change over time in the content of a plurality of marker substances caused by reperfusion; At a first timing during reperfusion of the organ for transplantation, collect a first tissue sample from the organ for transplantation; At a second timing later than the first timing during the reperfusion, collect a second tissue sample from the organ for transplantation; Measure the content of the plurality of marker substances in the first tissue sample; Measure the content of the plurality of marker substances in the second tissue sample; For each of the plurality of marker substances, calculate the change in the content at the second timing relative to the content at the first timing; and Use the data and the calculated change in the content to calculate an index related to the evaluation of the function of the organ for transplantation, wherein, the step of calculating the change includes a step of calculating the change trend of the content for each of the plurality of marker substances, the step of calculating the index includes a step of scoring the change trends of the content of the plurality of marker substances using the data, the step of performing the scoring includes the following steps: the score when the change trend of the content in the organ for transplantation is consistent with the change trend of the content in the functionally normal organ of the data is higher than the score when the change trend of the content in the organ for transplantation is inconsistent with the change trend of the content in the functionally normal organ of the data, the step of calculating the index further includes calculating the sum of the scores of each marker substance among the plurality of marker substances as the index.

11. A device for evaluating the function of an organ for transplantation has an arithmetic unit. The device for evaluating the function of an organ for transplantation evaluates the function of an organ for transplantation removed from a living body, the device for evaluating the function of an organ for transplantation prepares data representing the change over time in the content of a plurality of marker substances caused by reperfusion, the arithmetic unit performs the following steps: Measure the content of the plurality of marker substances in a first tissue sample collected from the organ for transplantation at a first timing during reperfusion of the organ for transplantation; Measure the content of the plurality of marker substances in a second tissue sample collected from the organ for transplantation at a second timing later than the first timing during the reperfusion; For each of the plurality of marker substances, calculate the change in the content at the second timing relative to the content at the first timing; and Use the data and the calculated change in the content to calculate an index related to the evaluation of the function of the organ for transplantation, wherein, The steps of obtaining the change include steps of separately obtaining the change trends of the contents for the multiple marker substances. The steps of obtaining the index include steps of separately scoring the change trends of the contents of the multiple marker substances using the data. The steps of performing the scoring include the following steps: The score when the change trend of the content in the transplant organ is consistent with the change trend of the content in the functionally normal organ of the data is more than the score when the change trend of the content in the transplant organ is inconsistent with the change trend of the content in the functionally normal organ of the data. The steps of obtaining the index further include obtaining the sum value of the scores of each marker substance among the multiple marker substances as the index.

12. A computer program product, including a program for using a computer having an arithmetic unit to evaluate the function of a transplant organ removed from a living body, the program causing the arithmetic unit to execute the following steps: Prepare data representing the change over time of the contents of multiple marker substances caused by reperfusion. At a first timing during reperfusion of the transplant organ, collect a first tissue sample from the transplant organ. At a second timing during reperfusion that is later than the first timing, collect a second tissue sample from the transplant organ. Measure the contents of the multiple marker substances in the first tissue sample. Measure the contents of the multiple marker substances in the second tissue sample. Separate for the multiple marker substances obtain the change in the content at the second timing relative to the content at the first timing; and Use the data and the obtained change in the content to obtain an index related to the function evaluation of the transplant organ. Wherein, The steps of obtaining the change include steps of separately obtaining the change trends of the contents for the multiple marker substances. The steps of obtaining the index include steps of separately scoring the change trends of the contents of the multiple marker substances using the data. The steps of performing the scoring include the following steps: The score when the change trend of the content in the transplant organ is consistent with the change trend of the content in the functionally normal organ of the data is more than the score when the change trend of the content in the transplant organ is inconsistent with the change trend of the content in the functionally normal organ of the data. The steps of obtaining the index further include obtaining the sum value of the scores of each marker substance among the multiple marker substances as the index.

Images