Information processing device, information processing method, and program

Abstract

Provided is an information processing device, an information processing method, and a program which provide a means for more appropriately evaluating the state of a culture medium.　The information processing device includes: an acquisition unit that, in cell culture in which a culture medium containing a reagent the hue of which changes in accordance with pH is used, acquires a hue of interest of the culture medium to be evaluated during cell culture; a calibration data generation unit that generates calibration data for correcting the hue in accordance with the optical path length; a correction unit that corrects the hue of interest on the basis of the generated calibration data; and an evaluation unit that evaluates the change in the state of the culture medium in accordance with the corrected hue of interest or the pH based on the corrected hue of interest, or the rate of change in the hue or the pH per unit time based on the corrected hue of interest.

Description

Information processing device, information processing method, and program CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application is based on Japanese Patent Application No. 2023-216891 filed on December 22, 2023, the contents of which are incorporated herein by reference.

[0002] The present disclosure relates to an information processing device, an information processing method, and a program.

[0003] In recent years, the pharmaceutical industry has been seeking automation of development and production processes for the purposes of standardizing operations, improving production efficiency, and stabilizing quality and operations. In particular, biopharmaceuticals have products with large molecular weights and highly complex structures, which means that much of the development and production process requires manual labor, creating a high demand for labor-saving and automation. For example, even in cell culture, one of the development and production processes, most of the necessary work is performed manually, resulting in issues of reduced quality and productivity. In this regard, Patent Document 1 discloses a method for detecting contamination by contaminating bacteria, which is characterized by detecting the presence of contaminating bacteria in a culture medium based on changes in the absorption of visible light by the culture medium, and a technology for calculating the pH value of the culture medium based on changes in absorption of phenol red contained in the culture medium.

[0004] Japanese Patent Application Publication No. 01-035347

[0005] However, the relationship between pH and light absorption change is affected by the measurement conditions of the culture medium. For example, culture medium containers are made of glass, quartz, plastic, etc., and it is known that the transmittance of light wavelengths varies depending on the material. Therefore, from the perspective of performing a more accurate evaluation, it is preferable to consider the relationship between pH and hue corresponding to each measurement condition.

[0006] On the other hand, there are many parameters for the measurement conditions, such as cell type, medium type, and container material, making it difficult to grasp the relationship between pH and hue corresponding to each of the measurement conditions.

[0007] An object of the present disclosure is to provide an information processing device, an information processing method, and a program that provide means for more appropriately evaluating the state of a culture medium.

[0008] An information processing device according to one aspect of the present disclosure includes an acquisition unit that acquires a test hue of a culture medium to be evaluated during cell culture using a culture medium containing a reagent whose hue changes depending on pH, a calibration data generation unit that generates calibration data to correct the hue depending on the optical path length, a correction unit that corrects the test hue based on the generated calibration data, and an evaluation unit that evaluates a change in the state of the culture medium depending on the corrected test hue or the pH based on the corrected test hue, or the rate of change of the hue or pH per unit time based on the corrected test hue.

[0009] According to the present disclosure, it is possible to provide an information processing device, an information processing method, and a program that provide a means for more appropriately evaluating the state of a culture medium.

[0010] 1 is a diagram illustrating an example configuration of an information processing system according to an embodiment of the present disclosure; FIG. 2 is a diagram illustrating an example hardware configuration of an information processing device according to an embodiment of the present disclosure; FIG. 3 is a diagram illustrating an example functional block configuration of an information processing device according to an embodiment of the present disclosure; FIG. 4 is a diagram illustrating an example of calibration data; FIG. 5 is a diagram illustrating an example of a data set for generating calibration data; FIG. 6 is an image diagram illustrating how calibration data is generated; FIG. 7 is a diagram illustrating an example of calibration data (relational formula between pH and hue); FIG. 8 is a diagram illustrating an example of calibration data (correction coefficient derivation formula); FIG. 9 is an image diagram illustrating an embodiment of evaluation processing; FIG. 10 is a flowchart illustrating an example of processing procedures; FIG. 11 is a flowchart illustrating an example of processing procedures; FIG. 12 is a flowchart illustrating an example of processing procedures; FIG. 13 is a diagram illustrating an example of calibration data (theoretical formula); FIG. 14 is a diagram illustrating an example of processing procedures; FIG. 15 is a flowchart illustrating an example of processing procedures;

[0011] An embodiment of the present invention (hereinafter referred to as "the present embodiment") will be described with reference to the accompanying drawings, but the present invention is not limited to this and various modifications are possible without departing from the spirit of the present invention. In each drawing, parts with the same reference numerals have the same or similar configurations. The dimensional ratios of the drawings are not limited to those shown. The order of information processing steps can be arbitrarily changed or executed in parallel as long as no contradiction occurs in the processing content.

[0012] <System Configuration> Fig. 1 is a diagram showing an example of the configuration of an information processing system 1 according to this embodiment. The information processing system 1 shown in Fig. 1 acquires information about the hue of a cell culture medium 210 in a container 220 using an imaging device 200, and an information processing device 300 executes various processes necessary for determining changes in the state of the cell culture based on the acquired information. The imaging device 200 and the information processing device 300 are connected to each other so as to be able to communicate with each other via a wireless or wired communication network such as the Internet, an intranet, a wireless LAN, or mobile communication.

[0013] In this disclosure, a "culture medium" refers to a substance for culturing cells, and may be used interchangeably with "culture medium" or "culture solution," regardless of whether it is in liquid or solid form. The type of cells may be any, such as plant cells, animal cells, or microbial cells.

[0014] In this disclosure, the term "medium state" refers to the state of the medium being monitored, such as acidity, alkalinity, or overgrowth. Unless otherwise specified, it includes the current medium state and the future medium state. The medium state includes both normal and abnormal states. The medium state does not necessarily have to be one state; multiple states can exist simultaneously.

[0015] The imaging device 200 may be a conventionally known device. For example, an imaging device equipped with a color sensor may acquire the hue of the cell culture medium 210 as a parameter in any color space, such as RGB. A light source 240 emitting a predetermined light may be disposed on a stage 230 on which the container 220 is placed. This allows the known light emitted from the light source 240 to pass through the cell culture medium 210 at a predetermined optical path length and reach the imaging device 200, allowing the imaging device 200 to acquire the hue of the cell culture medium 210. While the present disclosure describes a case where information regarding the hue is acquired using the imaging device 200, a sensing device capable of acquiring information regarding the hue of the medium may also be used instead of the imaging device 200. For example, a photoelectric sensor, such as a color sensor or fiber sensor, capable of acquiring information regarding the hue may be used. 1 illustrates an example of a configuration in which a light source 240 is installed below a cell culture medium 210 and the imaging device 200 is installed above the cell culture medium 210 to acquire a hue, as an example of a case in which the imaging device 200 is used; however, the configuration is not limited to this. For example, the light source 240 may be installed above the cell culture medium 210, and the imaging device 200 or a sensing device may be installed below the cell culture medium 210 to acquire a hue. For example, the light source 240 and the imaging device 200, or the light source 240 and a sensing device, may be installed above the cell culture medium 210 to acquire a hue. For example, the light source 240 and the imaging device 200, or the light source 240 and a sensing device, may be installed below the cell culture medium 210 to acquire a hue.

[0016] The information processing device 300 is an information processing device that performs functions such as generating calibration data for evaluating changes in the state of a culture medium based on the hue acquired using the imaging device 200 and information input by a user. The information processing device 300 is not particularly limited as long as it has the above functions, and may be, for example, a desktop, laptop, or other computer. The information processing device 300 is a general-purpose computer and may be configured as a single computer or may be configured as multiple computers on a network N.

[0017] 2 is a diagram showing an example of the hardware configuration of the information processing device 300. The information processing device 300 has a processor 71 such as a CPU (Central Processing Unit) or a GPU (Graphical Processing Unit), a communication IF (Interface) 72 for wireless or wired communication, a storage device 73 such as a memory (e.g., RAM (Random Access Memory) or ROM (Read Only Memory)), a HDD (Hard Disk Drive) and / or an SSD (Solid State Drive), an input device 74 for accepting input operations, and an output device 75 for outputting information. The input device 74 is, for example, a keyboard, a touch panel, a mouse, and / or a microphone. The output device 75 is, for example, a display, a touch panel, and / or a speaker, etc. The processor 71, the communication IF 72, the storage device 73, the input device 74, and the output device 75 are connected by one or more communication buses 76.

[0018] <Functional Block Configuration> The components of the information processing device 300 of this embodiment will be described in detail below. FIG. 3 is a diagram showing an example of the functional block configuration of the information processing device 300. The information processing device 300 has a storage unit 310, an acquisition unit 320, a calibration data generation unit 330, a correction unit 340, an estimation unit 350, an evaluation unit 360, an output unit 370, and a sensitivity adjustment unit 380. The storage unit 310 can be realized using a storage device 73 included in the information processing device 300. The acquisition unit 320, the calibration data generation unit 330, the correction unit 340, the estimation unit 350, the evaluation unit 360, the output unit 370, and the sensitivity adjustment unit 380 can be realized by a processor 71 included in the information processing device 300 executing a program stored in the storage device 73. The program can be stored in a storage medium. The storage medium storing the program may be a non-transitory computer-readable medium. The non-transitory storage medium is not particularly limited, and may be, for example, a Universal Serial Bus (USB) memory or a Compact Disc Read-Only Memory (CD-ROM).

[0019] <Storage Unit> The storage unit 310 stores various data necessary for the information processing device 300 to execute the information processing method of the present disclosure.

[0020] <Acquisition Unit> The acquisition unit 320 has a function of acquiring a test hue, measurement conditions when acquiring the test hue, and various data sets for generating calibration data. In the present disclosure, "acquire" means accepting information input by a user or receiving information acquired using the imaging device 200.

[0021] The acquisition unit 320 has a function of acquiring a test hue. In the present disclosure, the "test hue" refers to the hue of the culture medium to be evaluated. In the present disclosure, when there is no particular distinction between whether the culture medium of the hue to be acquired is the one to be evaluated or the one prepared for generating calibration data, the term "hue" is used. For example, when the imaging device 200 captures an image of the cell culture medium 210 in the container 220, the acquisition unit 320 acquires information about the test hue as parameters of an arbitrary color space such as RGB from the image information. If the imaging device 200 is capable of outputting a signal related to parameters of an arbitrary color space such as RGB by capturing an image of the cell culture medium 210, the acquisition unit 320 may acquire the signal as information about the test hue.

[0022] In one embodiment, the acquisition unit 320 may acquire the test hue together with time-series data. This enables evaluation of changes in the state of the culture medium over time during cell culture. For example, the imaging device 200 may continuously capture images of the hue of the cell culture medium 210, and the acquisition unit 320 may continuously acquire information about the hue from the imaging device 200, and acquire the hue at any one or more time points as the first test hue, the second test hue, the third test hue, etc. In another embodiment, the imaging device 200 may intermittently capture images of the hue of the cell culture medium 210, and the acquisition unit 320 may intermittently acquire information about the test hue from the imaging device 200, and acquire the hue at any one or more time points as the first test hue, the second test hue, the third test hue, etc.

[0023] In one aspect, the acquisition unit 320 has a function of acquiring measurement conditions when acquiring the test hue. For example, the acquisition unit 320 acquires the optical path length h2 in the cell culture medium 210 when acquiring the test hue based on the distance h0 and the distance h1. In the present disclosure, "measurement conditions" include, for example, the cell type, the medium type, the pH indicator type, the container type, the optical path length, pH, and any other parameters. A plurality of measurement conditions may be acquired for the test hue, for example, in chronological order.

[0024] In one aspect, the acquisition unit 320 has a function of acquiring various data sets for generating calibration data. For example, the acquisition unit 320 acquires information about hue as a parameter of any color space such as RGB from image capture information acquired by the image capture device 200, or acquires information about hue input by a user. In the present disclosure, "calibration data" refers to information about the relationship between pH and hue corresponding to each measurement condition, such as a pH test reagent type or a cell type, and is used for data correction and calibration processes, such as correcting hue according to the optical path length.

[0025] Information regarding the relationship between pH and hue contained in the calibration data includes, for example, a relationship equation between pH and hue, a relationship equation between the optical path length h2 and hue, a relationship equation between the optical path length and pH, a theoretical formula showing the relationship between the optical path length and hue, a correction coefficient derivation formula for deriving a correction coefficient, a relationship equation between pH, hue and optical path length, and a correction formula for correcting hue.

[0026] FIG. 4 shows an example of calibration data. In the example of FIG. 4, information on the relationship between pH and hue is shown as table 500 for each hue measurement condition. As shown in FIG. 4, items of measurement conditions included in the calibration data include items such as cell type, culture medium type, pH indicator type, container type, optical path length, and other arbitrary parameters. Items of information on the relationship between pH and hue included in the calibration data include a first relational expression, a second relational expression, a correction coefficient, a correction formula, etc. Each item of measurement condition and information on the relationship between pH and hue has a respective value. For example, according to calibration data table 500, for the hue measured under measurement conditions of cell type "XX", culture medium type "△△", pH indicator type "phenol red", container type "XX", and optical path length "L1", the first relational expression "C1=f １ (ph)”, the second relational expression “Cany=j １ (ph, h(L １ ))) and the correction coefficient "r １ ”, correction formula “Cm=Cs*r １ It is noted that " applies.

[0027] In the present disclosure, a "dataset for generating calibration data" is information used to generate calibration data, and is a combination of information on measurement conditions and information measured under predetermined measurement conditions. For example, it is a combination of information on measurement condition M, which is cell type: A, medium type: B, pH indicator type: C, and optical path length: D, and information on hue: E measured under measurement condition M.

[0028] The information constituting the data set for generating calibration data may be obtained based on actual measurements by the user or on values ​​set by the user. In this disclosure, an "actual measurement value" is a value obtained by measurement, and a "set value" is a value obtained by user input or setting without measurement. Neither value is limited to being a numerical value.

[0029] FIG. 5 shows an example of a data set for generating calibration data. In the example of FIG. 5, table 100 shows a combination of information on measurement conditions and information on hues measured under those measurement conditions. Table 100 is a combination of tables 110, 120, and 130, which are acquired data sets. Table 110 shows a combination of information on measurement conditions, i.e., a predetermined cell type (Hela cell), various pH values ​​at a predetermined optical path length (10 mm), and information on hues (R values) corresponding to each of those measurement conditions. Table 120 shows a combination of information on measurement conditions, i.e., a predetermined cell type (Hela cell), various optical path lengths at a predetermined pH (6), and information on hues (R values) corresponding to each of those measurement conditions. Table 130 shows a combination of information on measurement conditions, such as various optical path lengths at a specific cell type (Hela cell) and a specific pH (7), and information on the hue (R value) corresponding to each of the measurement conditions.

[0030] In one aspect, the acquisition unit 320 acquires various data sets for generating calibration data by setting one or more predetermined items of the measurement conditions as fixed values ​​and setting one or more predetermined items of the measurement conditions as variable values. The user may select which items are fixed values ​​and which are variable values. For example, the data set table 110 shown in FIG. 5 is a data set acquired with the cell type and optical path length as fixed values ​​and pH as a variable value. For example, the data sets tables 120 and 130 shown in FIG. 5 are data sets acquired with the cell type and pH as fixed values ​​and the optical path length as a variable value.

[0031] <Calibration Data Generation Unit> The calibration data generation unit 330 has a function of generating calibration data that corrects the hue according to the optical path length. For example, the calibration data generation unit 330 generates calibration data corresponding to the measurement conditions of a predetermined hue from information acquired by the acquisition unit 320 or information input by the user, and stores the calibration data in the storage unit 310 in association with the measurement conditions.

[0032] Fig. 6 is an image diagram showing how calibration data is generated using data sets for generating calibration data. In the example of Fig. 6, charts 610, 620, and 630, which are calibration data, are generated based on table 110, table 120, and table 130, which are data sets for generating calibration data that have been acquired. Table 500, which is calibration data, is a combination of charts 610, 620, and 630.

[0033] By referring to the generated calibration data, it is possible to identify the relationship between pH and hue (first relational expression, second relational expression, etc.) that is applied for each predetermined measurement condition.

[0034] The calibration data generating unit may include a first relational equation creating unit 331 , a calculation unit 332 , and a second relational equation creating unit 333 .

[0035] (First Relational Equation Creation Unit) The first relational equation creation unit 331 has a function of creating a first relational equation that indicates the relationship between pH and a first hue. For example, the first relational equation creation unit 331 creates a relational equation 41 between pH and hue as shown in FIG. 7 based on a data set for generating calibration data acquired by the acquisition unit 320. The example in FIG. 7 shows a function C1=f(ph) that determines hue relative to pH at an optical path length of 15 mm. For example, it is referenced that at an optical path length of 15 mm, the hue is 110 when pH=7, the hue is 100 when pH=7.2, etc.

[0036] (Calculation Unit) The calculation unit 332 has a function of calculating a correction coefficient for correcting the hue in accordance with the optical path length based on the second hue. For example, the calculation unit 332 creates a correction coefficient derivation formula 61 as shown in FIG. 8 and calculates the correction coefficient to be applied for the optical path length by introducing the optical path length into the correction coefficient derivation formula 61. The calculation unit 332 creates the correction coefficient derivation formula 61 based on, for example, the theoretical relationship between hue and pH and the second hue. In the example of FIG. 8, a function r=h(L) is shown that determines the correction coefficient (r) with respect to the optical path length (L). For example, １ ) the hue measured under the measurement conditions is adjusted by a correction coefficient r １ 13 may be used to create the correction coefficient derivation formula 61.

[0037] (Second Relational Expression Creation Unit) The second relational expression creation unit 333 has a function of creating a second relational expression that indicates the relationship between hue and a predetermined optical path length based on the first relational expression and the correction coefficient. For example, the second relational expression creation unit 333 combines the relational expression calculated by the first relational expression creation unit 331 with the correction coefficient (rx) that should be applied in the case of the optical path length (Lx) calculated by the calculation unit 332 to create the second relational expression that indicates the relationship between hue and optical path length (Lx).

[0038] <Correction Unit> The correction unit 340 has a function of correcting the test hue based on the calibration data generated by the calibration data generation unit 330. For example, the correction unit 340 refers to the calibration data and calculates a corrected test hue (Cm) from the test hue (Cs) and a correction coefficient (rs) corresponding to the optical path length (Ls) when measuring the test hue.

[0039] The estimation unit 350 has a function of calculating an estimated pH corresponding to the corrected test hue based on the second relational expression. For example, the estimation unit 350 calculates an estimated pH (phe) by incorporating the optical path length (Ls) at the time of measuring the test hue and the corrected test hue (Cm) corrected by the correction unit 340 into the second relational expression that indicates the relational expression of the hue to the optical path length (Lx).

[0040] <Evaluation Unit> The evaluation unit 360 has a function of evaluating a change in the state of the culture medium. In this disclosure, unless otherwise specified, "a change in the state of the culture medium" includes "a current change in the state of the culture medium" and "a future change in the state of the culture medium." In this disclosure, "evaluating" includes "determining."

[0041] In one embodiment, the evaluation unit 360 evaluates the change in the state of the culture medium based on the corrected test hue corrected by the correction unit 340 and the estimated pH corresponding to the corrected test hue calculated by the estimation unit 350. For example, the evaluation unit 360 evaluates the change in the state of the culture medium based on whether or not the corrected test hue exceeds a predetermined hue range. Specifically, the evaluation unit 360 may evaluate the change in the state of the culture medium as being normal if the corrected test hue is within the predetermined hue range, and as being abnormal if the corrected test hue is outside the predetermined hue range. Furthermore, for example, the evaluation unit 360 may evaluate the change in the state of the culture medium based on whether or not the estimated pH corresponding to the corrected test hue exceeds a predetermined pH range. Specifically, the evaluation unit 360 may evaluate the change in the state of the culture medium as being normal if the estimated pH is within the predetermined pH range, and as being abnormal if the estimated pH is outside the predetermined pH range. Furthermore, for example, when the corrected test hue or estimated pH is approaching the boundary of a predetermined range, the evaluation unit 360 may evaluate that there is a possibility of an abnormality occurring in the culture medium. Specifically, the evaluation unit 360 tracks changes over time in the corrected test hue that is intermittently or continuously acquired by the acquisition unit 320 and corrected by the correction unit 340. This allows the evaluation unit 360 to detect that the corrected test hue or estimated pH is approaching the boundary of a predetermined range.

[0042] In one embodiment, the evaluation unit 360 evaluates the change in the state of the culture medium based on the amount of change in the corrected test hue and the amount of change in the estimated pH. For example, the state of the culture medium may be evaluated based on the amount of change Δ1 in the first corrected test hue and the second corrected test hue acquired and corrected at the first and second time points, and the amount of change Δ2 in the first estimated pH at the first time point and the second estimated pH at the second time point. This embodiment is particularly useful when the cell culture medium 210 is already colored before the addition of a reagent whose hue changes depending on pH. If the cell culture medium 210 before the addition of the reagent is colored by some other reagent or the color of the cells themselves, the test hue is a mixture of the color of the cell culture medium 210 before the addition of the reagent and the color of the reagent whose hue changes depending on pH. In other words, the test hue does not reflect only the color of the reagent whose hue changes depending on pH. In contrast, using the amount of change in hue as in this embodiment allows the color change of the reagent to be properly evaluated.

[0043] In one embodiment, the evaluation unit 360 evaluates the change in the state of the culture medium based on the rate of change of the corrected test hue or pH per unit time, which is based on the corrected test hue acquired in time series by the acquisition unit 320 and corrected by the correction unit 340. For example, the evaluation unit 360 evaluates the change in the state of the culture medium based on whether the rate of change exceeds a change rate threshold. The change rate threshold may be predetermined by the user. In the present disclosure, the "change rate threshold" indicates the range of acceptable changes in the culture medium. If the rate of change exceeds the change rate threshold, there is a possibility of problems, such as a sudden deterioration in the state of the culture medium. In other words, the change rate can also be used as a predictor of future changes in the state of the culture medium. Furthermore, for example, even if the change is within the change rate threshold, the accumulated changes may cause the pH to increase or decrease to an abnormal range. The "absolute value threshold" indicates the range of the hue or pH of the culture medium that is acceptable in such cases. Therefore, the evaluation unit 360 can determine the current change in the state of the culture medium by determining whether the estimated pH calculated based on the corrected test hue exceeds or is within the absolute value threshold. The absolute value threshold may be predetermined by the user.

[0044] In one embodiment, the evaluation unit 360 performs first-order or higher-order differentiation on the change in the corrected test hue acquired in time series by the acquisition unit 320 and corrected by the correction unit 340, or the change in pH based on the corrected test hue, to calculate the rate of change per unit time and evaluate the change in the state of the culture medium. For example, the evaluation unit 360 performs first-order or higher-order differentiation on the change in pH based on the corrected test hue to calculate a first-order or higher-order derivative, and evaluates the change in the state of the culture medium. For example, the change in the state of the culture medium is evaluated based on the extreme values ​​of the calculated first-order or higher-order derivatives, or the rate of change in hue or pH in a predetermined interval or at a predetermined time point calculated based on the extreme values. Multiple calculated derivatives may be combined and used for the evaluation. Using multiple derivatives in combination for the evaluation can improve the accuracy of the evaluation.

[0045] 9 is an image diagram for explaining the first-order differentiation and second-order differentiation of a change in hue over time. Fig. 9 shows the change over time of the corrected test hue ("RGB" in table 700, "f(t)" in chart 700) that is acquired intermittently or continuously by the acquisition unit 320 and corrected by the correction unit 340, a derivative calculated by first-order differentiation of the change over time of the corrected test hue using the ABS function ("f'(t)" in chart 700), and a derivative calculated by second-order differentiation using the ABS function ("f''(t)" in chart 700). By performing first-order and second-order differentiation in this manner, it becomes possible to capture sudden changes in hue and pH, thereby improving the accuracy of the evaluation. Furthermore, because sudden changes can be monitored as extreme values ​​on a graph, it becomes easier to determine the state of the culture medium and to output an evaluation that is highly visible to the user. In cell culture, for example, dramatic changes in the state of the culture medium due to the inclusion of foreign matter or the occurrence of contamination are expected, so it is considered that the ability to monitor sudden changes in pH and hue is of great significance. Furthermore, from the perspective of further improving the accuracy of the evaluation, additional mathematical processing such as smoothing may be performed.

[0046] In one embodiment, the evaluation unit 360 also has a function of estimating the cause of a change in the state of the medium. For example, when the change in the medium is acidification based on the corrected test hue and estimated pH, the evaluation unit 360 may estimate the cause as either a limit on the use of the medium or recent contamination, depending on the cell occupancy rate of the medium. Specifically, when the medium is acidified and the cell occupancy rate is excessive, the evaluation unit 360 may estimate that the medium has become acidic due to lactic acid released from the cells, causing environmental deterioration. Furthermore, when the medium is acidified and the cell occupancy rate is not high, the estimation unit 350 may estimate that bacterial proliferation in the medium due to contamination has led to the accumulation of metabolic products (lactic acid), resulting in acidification. Here, the cell occupancy rate of the medium may be acquired as confluency using the imaging device 200. Furthermore, when the change in the medium is alkalization, the cause may be decomposition of the medium's components, a decrease in the amount of carbon dioxide in the medium, an equipment malfunction in the culture equipment, or bacterial contamination, depending on the medium's temperature, carbon dioxide concentration, or imaging data of the medium. Specifically, if the medium is alkalized and there is a problem with the medium heating procedure, or if the medium temperature deviates from the set temperature, the evaluation unit 360 may infer that the decomposition of amino acids such as L-glutamic acid in the medium is accelerated, resulting in the generation of cytotoxic ammonia and other substances. Furthermore, if the medium is alkalized and the CO2 concentration sensor's observed value is low, the evaluation unit 360 may infer that the CO2 concentration in the cell culture atmosphere is too low, causing the medium to lose carbon dioxide and become alkalized. Furthermore, if imaging data or other data confirm that the medium is alkalized and there is a problem with the medium heating procedure, or that the medium is not covered, the evaluation unit 360 may infer that the medium is alkalized because the CO2 in the medium escapes into the atmosphere due to the medium lid being left on. Furthermore, if the medium is alkalized and none of the above conditions apply, the evaluation unit 360 may infer that contamination has caused bacteria to release amino acids as ammonium ions into the medium, resulting in alkalization. The medium temperature can be measured using a temperature sensor, and the carbon dioxide concentration can be measured using a CO2 sensor. Furthermore, imaging data of the culture medium can be measured by the imaging device 200.

[0047] <Output Unit> The output unit 370 has a function of outputting the evaluation results. The evaluation results may be information regarding the corrected test hue or estimated pH, or information regarding whether the corrected test hue or estimated pH falls within a predetermined range. The evaluation results may also be information regarding a current change in the state of the culture medium or information predicting a future change in the state of the culture medium. The output unit 370 may also output the estimated cause and a method for resolving the cause in addition to the evaluation results. The output method by the output unit 370 is not particularly limited, and may include outputting images or audio via a display device or speaker, outputting control instructions for other devices such as a culture device, or outputting the information as a production record to a process management system that manages the culture operation. For example, the resolving measure output by the output unit 370 may be an instruction for controlling the culture device (incubator). Specifically, if the resolving measure relates to the culture environment, such as the culture temperature or CO2 concentration, the output unit 370 may output instruction information for controlling the culture environment to the culture device.

[0048] <Sensitivity Adjustment Unit> When acquiring hue at multiple points in time, the sensitivity adjustment unit 380 can set a change rate threshold and / or a hue measurement interval according to the measurement sensitivity specified by the user. This allows the sensitivity based on the change rate to be adjusted. For example, by reducing the change rate threshold, even a slight change in the change rate can be predicted and detected, while also making it easier to detect noise.

[0049] <Operation> (Operation Example 1) Figure 10 is a flowchart showing one aspect of the processing procedure of the information processing device 300. The information processing device 300 acquires a pH-RGB data set (step S101). Based on the acquired pH-RGB data set, an "RGB-pH" relational equation for a predetermined optical path length is created (step S102). Also, RGB is measured for three or more optical path length patterns at the predetermined pH (step S303). A theoretical equation for absorbed light amount-optical path length is created, and the data measured in step S303 is fitted to this theoretical equation to obtain a relational equation between optical path length and RGB correction coefficients (step S304). A "corrected RGB-pH" relational equation is obtained from the relational equation created in step S102 and the relational equation obtained in step S304 (step S305). The RGB values ​​are obtained by actual measurement, the optical path length is obtained by inputting a fixed value or by actual measurement, corrected RGB is calculated from the relational expression obtained in step S304, and pH is obtained from the relational expression obtained in step S305 (step S306).

[0050] (Operation Example 2) Figure 11 is a flowchart showing one aspect of the processing procedure of the information processing device 300. The information processing device 300 acquires a data set for generating calibration data and a test hue (step S201). Calibration data is generated based on the acquired information (step S202). The test hue is corrected based on the generated calibration data (step S203). Changes in the state of the culture medium are evaluated based on the corrected test hue (corrected test hue) (step S204).

[0051] (Operation Example 3) Figure 12 is a flowchart showing one aspect of the processing procedure of the information processing device 300. The information processing device 300 acquires a first hue corresponding to various pH values ​​for a predetermined cell type (step S301-1). It creates a first relational expression showing the relationship between pH and the first hue (step S301-2). It acquires a second hue corresponding to various optical path lengths for a predetermined cell type and pH (step S302-1). It calculates a correction coefficient for correcting the hue according to the optical path length based on the second hue (step S302-2). It also acquires a test hue (step S303). It creates a second relational expression showing the relationship between the hue and a predetermined optical path length based on the created first relational expression and the calculated correction coefficient (step S304). It corrects the test hue according to the optical path length based on the calculated correction coefficient (step S305). It calculates an estimated pH corresponding to the corrected test hue based on the created second relational expression and the corrected test hue (corrected test hue) (step S306). The change in the state of the culture medium is evaluated according to (i) the corrected test hue and the estimated pH, or (ii) the rate of change in hue or pH per unit time based on the corrected test hue and the estimated pH (step S307).

[0052] 13 is a flowchart showing one example of the processing procedure of the information processing device 300. (Step S401-1: Acquisition of First Hue) The information processing device 300 acquires various arbitrary pH (phx) values ​​of cell types, culture medium types, pH indicator types, etc. under predetermined measurement conditions. １ , phx ２ , phx ３ The first hue (C1 １ , C1 ２ , C1 ３The measurement conditions include the cell type, medium type, pH indicator type, etc., and the optical path length. The measurement conditions include the cell type, medium type, pH indicator type, etc., and the optical path length. The table 110 shown in FIG. 6 is an example of information relating to the relationship between pH and hue under predetermined measurement conditions. The measurement conditions include the cell type, medium type, pH indicator type, etc., and the optical path length. The measurement conditions, such as the cell type, medium type, pH indicator type, etc., may be acquired from information captured by the imaging device 200 or from information input by the user. This step may be performed by the acquisition unit 320 of the information processing device 300.

[0053] (Step S401-2: Creation of First Relational Expression) From the information on the first hue (C1) acquired for various arbitrary pH values, a first relational expression is created that indicates the relationship between an arbitrary pH and the first hue under predetermined measurement conditions for the cell type, medium type, pH indicator type, etc. The first relational expression is a function as shown in FIG. 7 and is expressed, for example, as "first hue (C1) = f(ph)." This step may be performed by the calibration data generation unit 330 of the information processing device 300.

[0054] (Step S402-1: Acquisition of Second Hue) Step S401-1 and the second hue are the same as those in Step S401-1. １ , Lx ２ , Lx ３ The second hue (C2) corresponds to １ , C2 ２ , C2 ３The pH (phx) is then acquired. At this time, the arbitrary pH (phx) is included as a fixed value in the measurement conditions. This makes it possible to collect information regarding the relationship between the optical path length and hue under predetermined measurement conditions for the cell type, medium type, pH indicator type, etc., and pH. Tables 120 and 130 shown in FIG. 6 are examples of information regarding the relationship between the optical path length and hue under predetermined measurement conditions for the cell type, medium type, pH indicator type, etc. The measurement conditions for the cell type, medium type, pH indicator type, etc. may be acquired from information captured by the imaging device 200, or may be acquired from information input by the user. This step may be performed by the acquisition unit 320 of the information processing device 300.

[0055] (Step S402-2: Creation of theoretical formula) A theoretical formula is created that shows the theoretical relationship of the change in the amount of absorbed light (ΔI) with respect to the optical path length (L) or concentration (C). Here, the concentration is, for example, the concentration of the culture medium. For example, the theoretical formula is created using the Lambert-Beer law of absorbance. The measurement of the test hue by the imaging device 200 involves detecting the transmitted light that is generated when light emitted from the light source 240 passes through the cell culture medium 210 at a predetermined optical path length, and acquiring the hue. In other words, the hue value acquired by the imaging device 200 corresponds to the amount of absorbed light of a predetermined color in the culture medium. For this reason, calculation formulas related to absorbance, such as "absorbance (A) = extinction coefficient (ε) * molar concentration (C) * optical path length (L)" and "absorbance (A) = log(I ０ / I), I ０ A theoretical formula can be created using "where ΔI is the incident light intensity and I is the transmitted light intensity." FIG. 14 shows an example of creating a theoretical formula using Lambert-Beer's law. The theoretical formula is a function as shown in FIG. 14, and is expressed as, for example, "absorbed light amount (ΔI) = f (optical path length L)" or "absorbed light amount (ΔI) = f (concentration C)." This step may be performed by the calibration data generation unit 330 of the information processing device 300.

[0056] (Step S402-3: Creation of Correction Coefficient Derivation Formula) The information on the second hue (C2) acquired for various optical path lengths is fitted to the theoretical formula created in step S401-2 to create a correction coefficient derivation formula for deriving a correction coefficient. For example, for various optical path lengths or concentrations, multiple calculations are performed for "correction coefficient = [second hue (Cmax) that reaches a plateau due to a sufficient optical path length] / [second hue (C2) corresponding to an arbitrary optical path length Lx]," and the calculation results are combined to create a correction coefficient derivation formula that determines the correction coefficient (r) depending on the optical path length or concentration. The correction coefficient derivation formula is a function such as that shown in FIG. 8, and is expressed as, for example, "correction coefficient (r) = h (optical path length L)." This step may be performed by the calibration data generation unit 330 of the information processing device 300.

[0057] Figures 15 and 16 relate to the creation of the correction coefficient derivation formula. The left diagram in Figure 15 is an image of the formula showing the relationship between light path length and G absorption, where the horizontal axis represents a predetermined liquid depth (light path length) and the vertical axis represents G absorption (actually measured value) under predetermined measurement conditions, with the pH set to a fixed value of 8.4 and other cell types, medium types, pH indicator types, etc. The right diagram is an image of the theoretical formula created in step S401-2. As shown in Figure 15, the G absorption varies greatly depending on the light path length, but as the light path length increases, the difference in absorption due to the light path length decreases. Furthermore, as shown in the theoretical formula showing the theoretical relationship between light path length and absorbed light amount in Figure 14, the variation in absorbed light amount decreases as the light path length increases. Figure 16 shows data indicating that as the light path length increases, the relationship between RGB and pH approaches the theoretical RGB-pH relationship. For example, when comparing the measured G value of a hue corresponding to an optical path length of 15 mm with a hue corresponding to an optical path length of 25 mm, the hue corresponding to the optical path length of 25 mm has a value closer to the theoretical value. Therefore, it is preferable to use the amount of absorbed light corresponding to an optical path length at which the variation in the amount of absorbed light is small (an optical path length sufficient for the hue to reach a plateau) as the true value. Examples of optical path lengths at which the variation in the amount of absorbed light is small include 25 mm or more, 20 mm or more, and 18 mm or more. By correcting the hue in this way according to the optical path length, a more accurate evaluation can be achieved.

[0058] (Step S403: Obtaining Test Hue) The information processing device 300 obtains the test hue (Cs) from the information captured by the imaging device 200. The optical path length at which the test hue (Cs) is obtained is defined as the optical path length (Ls). This step may be performed by the obtaining unit 320 of the information processing device 300.

[0059] (Step S404: Creation of Second Relational Equation) A second relational equation showing the relationship between hue and a predetermined optical path length is created based on the first relational equation created in step S401-2 and the correction coefficient derivation equation created in step S402-3. For example, an arbitrary optical path length (Lx) is introduced into the correction coefficient derivation equation, "correction coefficient (r) = h (optical path length L)," to calculate a correction coefficient rx corresponding to the optical path length Lx. Then, the correction coefficient (rx) corresponding to the optical path length (Lx) is combined with the first relational equation, "first hue (C1) = f (ph)," created in step S401-2, which shows the relationship between pH and the first hue corresponding to the optical path length (Lx), to create a second relational equation showing the relationship between hue and optical path length (Lx). The second relational equation can be expressed, for example, as "hue (Cany) = f (ph, h (Lx))." The second relational expression makes it possible to refer to the relationship between pH, optical path length, and hue under predetermined measurement conditions for a cell type, etc. This step may be performed by the calibration data generating unit 330 of the information processing device 300.

[0060] (Step S405-1: Creation of Correction Formula) A correction formula for correcting the test hue according to the optical path length is created. The correction formula is expressed as, for example, "corrected test hue (Cm) = test hue (Cs) * correction coefficient (rs) corresponding to optical path length Ls." The correction coefficient (rs) corresponding to optical path length Ls can be calculated by introducing the optical path length (Ls) into the correction coefficient derivation formula "correction coefficient (r) = h (optical path length L)" created in step S402-3. This step may be performed by the correction unit 340 of the information processing device 300.

[0061] (Step S405-2: Calculation of corrected test hue) Using the correction formula created in step S405-1, a corrected test hue is calculated by correcting the test hue according to the optical path length. For example, the corrected test hue (Cm) can be calculated by introducing the correction coefficient (rs) and the test hue (Cs) into the correction formula "corrected test hue (Cm) = test hue (Cs) * correction coefficient (rs) corresponding to optical path length Ls." This step may be performed by the correction unit 340 of the information processing device 300.

[0062] (Step S406: Calculation of Estimated pH Corresponding to Corrected Test Hue) Using the second relational expression and the corrected test hue, an estimated pH (phe) corresponding to the corrected test hue is calculated. For example, by incorporating the optical path length (Ls) at the time of acquiring the test hue and the corrected test hue (Cm) into the second relational expression "hue (Cany) = f(ph, h(Lx))," the estimated pH corresponding to the corrected test hue can be calculated. This step may be performed by the estimation unit 350 of the information processing device 300.

[0063] (Step S407: Evaluation of Change in Culture Medium State) The change in culture medium state is evaluated based on the corrected test hue (Cm) calculated in step S405-2 and the estimated pH (phe) calculated in step S406. This step may be performed by the evaluation unit 360 of the information processing device 300.

[0064] (Operation Example 5) Figure 17 is a flowchart showing one aspect of the processing procedure of the information processing system 1 of this embodiment. Conventional cell culture devices with a culture medium replacement function include those that store cell dishes in a storage rack within the device and remove them at regular intervals to replace the culture medium, and those that place cell dishes on a turntable and replace the culture medium when the turntable rotates and moves the cell dish to the culture medium replacement position. However, in such cell culture devices, the culture medium replacement process continues without detecting, for example, foreign matter that interferes with normal cell growth. In such conventional devices, a decision is made to discard the cells if an abnormality is discovered, for example, through periodic visual observation of the cells. However, because some types of cells are extremely rare and expensive, minimizing waste and suppressing increases in production costs has been a major challenge in cell culture. In contrast, the information processing system 1 of this embodiment makes it possible to realize a cell culture device equipped with a pH measurement (estimation) function. For example, the pH can be measured from the color of the cell culture medium at set intervals in parallel with cell culture. In addition to the usual periodic medium replacement flow, a replacement flow when the pH is abnormal can be added, improving the quality of cell culture and reducing waste.

[0065] One aspect of the processing procedure shown in Fig. 17 will be described. Steps S501 to S504 are an example of a flow for replacement when the pH is abnormal. Steps S601 to S610 are an example of a flow for regular medium replacement. The order of steps S501 to S504 and steps S601 to S610 can be arbitrarily changed or executed in parallel as long as no contradiction occurs in the content.

[0066] The user sets a cell culture execution plan. For example, a culture medium replacement schedule is set (step S601). Specifically, the user sets, for example, the timing of culture medium replacement, the type of culture medium, the culture medium supply rate, the culture medium supply amount, etc. Also, for example, the user sets the culture medium pH determination (step S501). Specifically, the user sets, for example, the measurement interval for the hue of the culture medium, the type of culture medium, the determination threshold level, etc.

[0067] The user places the culture medium on the storage rack (step S602).

[0068] The information processing system 1 determines whether to continue the cell culture (step S603). Here, the determination of whether to continue the cell culture may be made depending on the type of cells to be cultured and the purpose of the culture, or may be made based on the outputs from steps S501 to S504.

[0069] If it is determined that the cell culture should be continued (step S603: YES), the system waits until the timing for changing the culture medium (step S604), and when the timing for changing the culture medium arrives, the culture medium is removed (step S605). The culture medium is changed (step S606).

[0070] Furthermore, if it is determined that cell culture should be continued (step S603: YES), the hue of the culture medium is measured at the set measurement interval (step S502). An estimated pH is calculated based on the measured hue and the color-pH relationship equation (step S503). The information processing system 1 determines whether the pH change rate is within the normal range (step S504-1). If it is determined that the pH change rate is within the normal range (step S504-1: YES), the process returns to step S502, where the hue of the culture medium is measured at the set measurement interval. If it is determined that the pH change rate is not within the normal range (step S504-1: NO), the culture medium is replaced (step S606). The information processing system 1 determines whether the pH range is within the safe range (step S504-2). If it is determined that the pH range is within the safe range (step S504-2: YES), the process returns to step S502, where the hue of the culture medium is measured at the set measurement interval. If it is determined that the pH range is not within the safe range (step S504-2: NO), the culture medium is replaced (step S606).

[0071] If it is determined that the cell culture should not be continued (step S603: NO), the process proceeds to a cell state observation step (step S607). The cell state observation step includes observing the state of the cells and acquiring information about the state of the cells.

[0072] The information processing system 1 determines whether the cell growth is normal (step S608). If it is determined that the cell growth is normal (step S608: YES), the system proceeds to a storage step (step S609). The storage step may include controlling the storage conditions of the cultured cells. For example, it may include managing information such as the storage temperature of the cultured cells, the date and time of storage, the storage facility, the status inside the storage cabinet, and the number of cells stored. If it is determined that the cell growth is not normal (step S608: NO), the system proceeds to a disposal step (step S610). The disposal step may include managing information regarding the timing and number of cells to be discarded.

[0073] <Program> A program according to one aspect of the present invention causes one or more information processing devices to execute the following steps in a cell culture using a culture medium containing a reagent whose hue changes depending on pH: an acquisition step of acquiring a test hue of a culture medium to be evaluated during the cell culture; a calibration data generation step of generating calibration data that corrects the hue depending on the optical path length; a correction step of correcting the test hue based on the generated calibration data; and an evaluation step of evaluating a change in the state of the culture medium depending on the corrected test hue or the pH based on the corrected test hue, or the rate of change of the hue or pH per unit time based on the corrected test hue.

[0074] 1...information processing system, 41...relational equation between pH and hue, 51a...theoretical equation, 51b...theoretical equation, 61...correction coefficient derivation equation, 71...processor, 72...communication IF, 73...storage device, 74...input device, 75...output device, 76...communication bus, 200...imaging device, 210...cell culture medium, 220...container, 230...stage, 240...light source, 300...information processing device, 310...storage unit, 320...acquisition unit, 330...calibration data generation unit, 331...first relational equation creation unit, 332...calculation unit, 333...second relational equation creation unit, 340...correction unit, 350...estimation unit, 360...evaluation unit, 370...output unit, 380...sensitivity adjustment unit

Claims

1. An information processing device comprising: an acquisition unit that acquires a test hue of a culture medium to be evaluated during cell culture using a culture medium containing a reagent whose hue changes depending on pH; a calibration data generation unit that generates calibration data that corrects the hue depending on an optical path length; a correction unit that corrects the test hue based on the generated calibration data; and an evaluation unit that evaluates a change in the state of the culture medium depending on the corrected test hue or a pH based on the corrected test hue, or a rate of change of hue or pH per unit time based on the corrected test hue.

2. The information processing device according to claim 1, wherein the generated calibration data includes at least one relational expression between optical path length and hue, optical path length and pH, and hue and pH.

3. The information processing device of claim 1, wherein the data set for generating the calibration data is obtained by setting the cell type, medium type, pH indicator type, and container type of the cell culture as fixed values ​​and acquiring the optical path length of the cell culture as a variable value, or by acquiring one or more of the cell type, medium type, pH indicator type, optical path length, container type, and any other parameters selected by a user as fixed or variable values.

4. The information processing device according to claim 1, wherein the data set for generating the calibration data is acquired based on actual measurements taken by a user.

5. The information processing device according to claim 1, wherein the data set for generating the calibration data is acquired based on a value set by a user.

6. The data set for generating the calibration data includes a first hue corresponding to one or more predetermined pHs for a predetermined cell type, medium type, and container type of the cell culture, and a second hue corresponding to one or more predetermined optical path lengths for the predetermined cell type, medium type, container type, and pH of the cell culture, and the calibration data generating unit includes: a first relational equation creating unit that creates a first relational equation showing a relationship between pH and the first hue; a calculation unit that calculates a correction coefficient for correcting the hue according to the optical path length based on the second hue; and a second relational equation creating unit that creates a second relational equation showing a relationship between the hue and a predetermined optical path length based on the first relational equation and the correction coefficient, and the correction unit corrects the test hue according to the optical path length based on the correction coefficient, 2. The information processing device according to claim 1, wherein the evaluation unit calculates an estimated pH corresponding to the test hue based on the corrected test hue and the second relational equation, and evaluates a change in the state of the culture medium according to the corrected test hue and the estimated pH, or a rate of change of hue or pH per unit time based on the corrected test hue and the estimated pH.

7. The information processing device according to claim 1, further comprising an output unit that outputs a result of the evaluation.

8. A program that causes an information processing device to execute the following steps: an acquisition step for acquiring a test hue of a culture medium to be evaluated during cell culture using a culture medium containing a reagent whose hue changes depending on pH; a calibration data generation step for generating calibration data that corrects the hue depending on the optical path length; a correction step for correcting the test hue based on the generated calibration data; and an evaluation step for evaluating a change in the state of the culture medium depending on the corrected test hue or pH based on the corrected test hue, or the rate of change of hue or pH per unit time based on the corrected test hue.

9. An information processing method comprising: an information processing device performing an acquisition step of acquiring a test hue of a culture medium to be evaluated during cell culture using a culture medium containing a reagent whose hue changes depending on pH; a calibration data generation step of generating calibration data that corrects the hue depending on the optical path length; a correction step of correcting the test hue based on the generated calibration data; and an evaluation step of evaluating a change in the state of the culture medium depending on the corrected test hue or pH based on the corrected test hue, or the rate of change of hue or pH per unit time based on the corrected test hue.

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