Cell observation device, method for operating cell observation device, and program for operating cell observation device

Abstract

This cell observation device comprises: an imaging device that captures an image of a cell contained in a cell suspension flowing through a flow path; a density detection mechanism for detecting the density of cells in the cell suspension; a dilution mechanism for diluting the cell suspension in the flow path; and a processor for diluting the cell suspension to control the density of the cells to a preset target density as a density suitable for imaging by the imaging device.

Description

CELL OBSERVATION DEVICE, METHOD FOR OPERATION OF CELL OBSERVATION DEVICE, AND OPERATION PROGRAM FOR CELL OBSERVATION DEVICE

[0001] The technology of the present disclosure relates to a cell observation device, an operating method for a cell observation device, and an operating program for a cell observation device.

[0002] A cell culture system (see, for example, International Publication No. WO 2015 / 069616) is known that cultures cells using a culture vessel. The culture vessel contains a cell suspension in which cells are suspended in a culture medium. When culturing cells, it is necessary to appropriately determine process conditions for the culture process, such as temperature control of the culture vessel, concentration control of the cell suspension in the culture vessel, and control of components of the culture medium, such as vitamins and amino acids.

[0003] In order to determine appropriate process conditions, it is necessary to understand the cell quality, which is the state of the cells during cultivation, and take this understood cell quality into consideration. To achieve this, cells are extracted from the culture vessel during cultivation, transferred to a container such as a petri dish, and observed to determine cell quality. However, because this type of offline inspection is time-consuming and labor-intensive, inline inspection techniques are being considered, in which cells are observed inline while flowing through a flow channel during cultivation. Cell observation devices such as phase-contrast microscopes and 3D image measurement using digital holography technology are used.

[0004] However, when observing cells inline, the density of cells flowing through the flow channel changes. In this case, capturing images of cells at high densities can result in poor image quality. This is because, for a given amount of illumination light used for imaging, the higher the cell density, the less exposure there is. Therefore, if the cell density is too high, the appropriate exposure cannot be obtained, resulting in poor contrast. Cell images with low contrast cannot accurately assess cell quality, which can hinder the determination of appropriate process control conditions.

[0005] The technology of the present disclosure provides a cell observation device, an operating method for a cell observation device, and an operating program for a cell observation device that are capable of acquiring cell images with better image quality than conventional devices.

[0006] In order to achieve the above-mentioned objective, the cell observation device according to the technology disclosed herein comprises an imaging device that captures images of cells contained in a cell suspension flowing through a flow path, a density detection mechanism that detects the density of cells in the cell suspension, a dilution mechanism that dilutes the cell suspension in the flow path, and a processor that dilutes the cell suspension to control the cell density to a target density that is preset as a density suitable for imaging by the imaging device.

[0007] The density detection mechanism preferably detects the density by analyzing an image obtained through the imaging device.

[0008] The imaging device is preferably an image measurement device that uses digital holography technology.

[0009] The density detection mechanism is preferably a mechanism separate from the image capture device, and detects the density in a section of the flow path upstream of the image capture device.

[0010] Furthermore, the processor preferably has a function of determining process conditions for the cell culture process based on the image.

[0011] The flow channel is preferably extracted from a culture vessel for culturing cells, and is a flow channel through which a cell suspension containing cells in the middle of culturing flows.

[0012] The method of operating a cell observation device according to the disclosed technology is a method of operating a cell observation device equipped with an imaging device that captures images of cells contained in a cell suspension flowing through a flow path, and by detecting the density of cells in the cell suspension and diluting the cell suspension, the cell density is controlled to a target density that is preset as a density suitable for imaging by the imaging device.

[0013] The operating program of a cell observation device according to the technology of the present disclosure is an operating program of a cell observation device that includes an imaging device that captures images of cells contained in a cell suspension flowing through a flow path, and a processor, and causes the processor to execute processes including detecting the density of cells in the cell suspension, and diluting the cell suspension to control the cell density to a target density that is preset as a density suitable for imaging by the imaging device.

[0014] According to the technology of the present disclosure, cell images of better image quality than conventional ones can be obtained.

[0015] 1 is a diagram showing an overview of a cell culture system incorporating a cell observation device. FIG. 2 is a block diagram showing the hardware configuration of the cell observation device. FIG. 3 is a diagram showing a photographing unit using digital holography technology. FIG. 4 is a diagram conceptually showing the principle of interference fringe generation and an interference fringe image. FIG. 5 is a diagram showing the positional relationship between a flow path member and a photographing unit. FIG. 6 is a diagram showing dilution control. FIG. 7 is a diagram showing a state where the density is higher than that of FIG. 7. FIG. 8 is a diagram showing a state where the density is higher than that of FIG. 8. FIG. 9 is a diagram showing the relationship between cell density and exposure dose. FIG. 10 is a diagram showing an example of control of a dilution control unit. FIG. 11 is a flowchart showing the operating procedure of the cell observation device. FIG. 12 is a diagram showing a cell observation device of a second embodiment. FIG. 13 is a diagram showing a cell observation device having a function of determining process control conditions.

[0016] 1, a cell observation device 11 is incorporated into a cell culture system 2. The cell culture system 2 contains a cell suspension 15 in which cells 13 are suspended in a culture solution 14, and includes a culture vessel 16 in which the cells 13 are cultured. In the cell culture system 2, the culture process of the cells 13 is appropriately managed.

[0017] To properly manage the culture process, it is necessary to determine appropriate process conditions, such as culture conditions. Culture conditions include the environmental conditions of the culture vessel 16, the conditions for replenishing components of the culture solution 14, and the timing of replacing the culture solution 14. The environmental conditions of the culture vessel 16 include the temperature of the culture vessel 16 and the agitation speed of the cell suspension 15 by the agitator 17. The conditions for replenishing components of the culture solution 14 include the amount and timing of replenishing components contained in the culture solution 14 by the addition device 18. Components of the culture solution 14 include a carbon source, vitamins, and amino acids. Management of the culture process includes state management of the cell suspension 15, such as removal of debris (dead cells and debris) from the cell suspension 15 and replacement of the culture solution 14. The culture controller 19 controls the culture process in this manner.

[0018] The cultured cells 13 or a product produced by the cells 13 are recovered from the culture vessel 16 for the next step through a culture recovery path 21. The process conditions also include the timing of recovery of the cultured cells 13.

[0019] In addition to the culture recovery path 21, an observation path 22 is provided in the culture vessel 16. A pump 23 is provided in the observation path 22, and the pump 23 extracts a cell suspension 15 containing cells 13 in the middle of culturing from the culture vessel 16. The cells 13 in the middle of culturing flowing through a flow path 29 of the observation path 22 are observed by the cell observation device 11.

[0020] The cell observation device 11 is used to grasp the cell quality of the cells 13 during culture in order to appropriately manage the culture process. That is, the cell observation device 11 performs in-line inspection of the cells 13 flowing through the flow path 29 of the observation path 22. Then, based on the cell quality of the cells 13 during culture, it is determined whether or not changes to process conditions, including culture conditions, are necessary and what changes to make are necessary. Furthermore, based on the cell quality, the timing for removing debris, the timing for replacing the culture medium 14, and the timing for recovering the culture product are determined.

[0021] The cell observation device 11 includes a control device 26 and a photographing unit 27. The photographing unit 27 is disposed on the observation path 22. The cells 13 flow through the observation path 22 and are photographed and stored in a storage section 30. Some of the cells 13 in the storage section 30 are returned to the culture vessel 16 and some are discarded, for example, depending on the state of the cells.

[0022] The photographing unit 27 has a light source 27A that emits illumination light L that illuminates the cell 13 to be observed, and an image sensor 27B that captures an optical image of the illuminated light source 27A. The cell observation device 11 is, for example, an image measurement device that uses digital holography technology. The cell observation device 11 measures, for example, an image that represents the three-dimensional shape of the cell 13. The image that represents the three-dimensional shape of the cell 13 is also called a three-dimensional image. By observing the three-dimensional shape of the cell 13, it is possible to more accurately grasp the cell quality. The photographing unit 27 is an example of an "imaging device" according to the technology of the present disclosure.

[0023] The image sensor 27B captures an interference fringe image 31 representing the interference state between the object light and the reference light as an optical image. The control device 26 controls the driving of the photographing unit 27 and performs image processing to reconstruct a cell image 32 representing the three-dimensional shape of the cell 13 based on the interference fringe image 31.

[0024] The cell quality of the cells 13 during culture is determined based on the cell image 32 acquired by the cell observation device 11, and process conditions including the culture conditions for the above-mentioned culture process are determined based on the determined cell quality. The culture process is controlled by the culture control device 19 according to the determined process conditions.

[0025] The cell observation device 11 also includes a dilution mechanism 34 that dilutes the cell suspension 15 in the flow path 29 of the observation path 22. The dilution mechanism 34 includes a culture medium tank 35, a pump 36, and a valve 37. The culture medium tank 35 contains the culture medium 14 for dilution. The pump 36 draws the culture medium 14 from the culture medium tank 35 into the observation path 22. The valve 37 opens and closes an inlet that allows the culture medium 14 from the culture medium tank 35 to flow into the observation path 22. When the culture medium 14 drawn up from the culture medium tank 35 is added to the observation path 22, the cell suspension 15 is diluted, and the density of the cells 13 can be reduced.

[0026] 2 , in the cell observation device 11, the control device 26 is configured by, for example, a computer. The control device 26 includes a storage 50, a memory 51, a CPU (Central Processing Unit) 52, a communication unit 53, a display 54, and an input device 55. These are interconnected via a bus line 56.

[0027] The storage 50 is a hard disk drive built into the computer that constitutes the control device 26 or connected via a cable or network. Alternatively, the storage 50 is a disk array consisting of multiple hard disk drives. The storage 50 stores control programs such as an operating system, various application programs, and various data associated with these programs. Note that a solid state drive may be used instead of a hard disk drive.

[0028] The memory 51 is a work memory for executing processes by the CPU 52. The CPU 52 loads programs stored in the storage 50 into the memory 51 and executes processes in accordance with the programs, thereby providing overall control over each part of the computer.

[0029] An operating program 58 according to the technology of the present disclosure is also stored in the storage 50. The operating program 58 is an application program for causing a computer to function as the cell observation device 11. By executing the operating program 58, the CPU 52 works in cooperation with the memory 51 to function as a processor 61 according to the technology of the present disclosure.

[0030] The communication unit 53 is a network interface that controls the transmission of various information via a network such as a LAN (Local Area Network). The display 54 displays various screens. The computer that constitutes the control device 26 accepts input of operation instructions from an input device 55 via the various screens. The input device 55 is a keyboard, a mouse, a touch panel, etc.

[0031] 3, the photographing unit 27 includes a light source 27A, an image sensor 27B, and a photographing optical system 66. As is well known, digital holography is a technology that utilizes the coherence of light to record light phase information in addition to light intensity information of an object to be observed, and then reconstructs a three-dimensional image of the object by using the recorded intensity information and phase information.

[0032] Digital holography utilizes the coherence of light and therefore uses coherent laser light as illumination light L. Light source 27A is a laser light source that emits laser light as illumination light L. Image sensor 27B is a two-dimensional image sensor having an imaging surface on which light-receiving elements are arranged two-dimensionally, and for example, a CMOS (complementary metal-oxide semiconductor) image sensor or the like is used.

[0033] An imaging optical system 66 is disposed on the optical path from the light source 27A to the image sensor 27B. The imaging optical system 66 includes, for example, a first reflecting mirror 66A, a beam splitter 66B, a second reflecting mirror 66C, an imaging lens LZ, a third reflecting mirror 66D, and a beam combiner 66E. The first reflecting mirror 66A reflects illumination light L emitted by the light source 27A toward the beam splitter 66B. The beam splitter 66B splits the illumination light L into an object light path toward the second reflecting mirror 66C and a reference light path toward the third reflecting mirror 66D.

[0034] A flow path 29 through which the cell 13 passes is disposed within the object light path including the second reflecting mirror 66C, and illumination light L reflected by the second reflecting mirror 66C is irradiated onto the cell 13. The illumination light L transmitted through the flow path 29 and the cell 13 is incident on an imaging lens LZ as object light OL. The imaging lens LZ focuses the object light OL and forms an optical image of the focused object light OL on the imaging surface of the image sensor 27B via a beam combiner 66E.

[0035] On the other hand, the illumination light L traveling along the reference light path from the beam splitter 66B to the third reflecting mirror 66D is incident on the third reflecting mirror 66D without passing through the flow path 29 through which the cells 13 flow. The illumination light L reflected by the third reflecting mirror 66D is incident on the beam combiner 66E as the reference light RL. Then, the illumination light L passes through the beam combiner 66E and is incident on the image sensor 27B.

[0036] As conceptually shown in Figure 4, the object light OL that passes through the flow path 29 and the cell 13 is diffracted by the cell 13 and the material that makes up the flow path 29, resulting in a curved wavefront. On the other hand, the reference light RL that does not pass through the flow path 29 and the cell 13 is a plane wave because it is not diffracted by the cell 13 or the like. Furthermore, the object light OL has a phase difference with respect to the reference light RL, and this phase difference has a magnitude that depends on the refractive index of the material that makes up the cell 13 and the flow path 29. The object light OL and the reference light RL interfere on the imaging surface 27BA of the image sensor 27B, generating interference fringes 67. The image sensor 27B captures the interference fringes 67 and outputs an interference fringe image 31.

[0037] The pixel value of each pixel in the interference fringe image 31 is the intensity of the interference fringes 67. In other words, the interference fringe image 31 is a two-dimensional distribution of the intensities of the interference fringes 67. The intensity of the interference fringes 67 changes in the imaging plane 27BA (XY plane) according to the phase difference between the object light OL and the reference light RL.

[0038] Of the lines representing the object light OL and the reference light RL, the solid lines indicate the wavefronts of the object light OL and the reference light RL with the maximum amplitude. In contrast, the dashed lines indicate the wavefronts of the object light OL and the reference light RL with the minimum amplitude. The white dots 68 shown on the imaging plane 27BA are areas where the wavefronts of the object light OL and the reference light RL are aligned and constructive with each other. The areas of these white dots 68 appear as bright areas 67A in the interference fringes 67. In contrast, the black dots 71 shown on the imaging plane 27BA are areas where the wavefronts of the object light OL and the reference light RL are shifted by half a wavelength and destructive with each other. The areas of these black dots 71 appear as dark areas 67B in the interference fringes 67.

[0039] For example, a digital holography image reconstruction method uses a plurality of interference fringe images 31 captured by changing the optical path difference between the object light OL and the reference light RL. Furthermore, for the illumination light L, for example, three or more interference fringe images 31 are acquired by capturing the illumination light L using different wavelengths. Based on these multiple interference fringe images 31, a cell image 32 representing the three-dimensional shape of the cell 13 is reconstructed.

[0040] 5, the flow path 29 is formed in, for example, a flow path member 74. The flow path member 74 is a flat plate-like member that is transparent to the illumination light L and is made of, for example, plastic. The flow path 29 is formed, for example, by forming a groove in a part of the flow path member 74, and the formed groove is sealed with a lid. Such a flow path member 74 is also called a micro-flow path device, etc.

[0041] The illumination light L passes through the flow path member 74 and the cells 13. Furthermore, because a cell suspension 15 containing cells 13 flows through the flow path 29, the illumination light L also passes through the culture solution 14 other than the cells 13 in the cell suspension 15. In the example shown in Fig. 5, the cross-sectional shape of the flow path 29 perpendicular to the flow direction is rectangular. Of course, the cross-sectional shape of the flow path 29 may also be circular. Furthermore, the flow path member 74 need not be a flat member, but may be a tube or the like.

[0042] For example, the photographing unit 27 repeatedly photographs still images of the interference fringe image 31 at preset intervals, thereby photographing the interference fringe image 31 showing the cells 13 flowing through the flow channel 29. Of course, the interference fringe image 31 may also be recorded as a moving image.

[0043] 6, the processor 61 of the control device 26 functions as an image processing unit 61A, an image acquisition condition determination unit 61B, and a dilution control unit 61C. The image processing unit 61A acquires an interference fringe image 31 from the photographing unit 27 and reconstructs a cell image 32 based on the acquired interference fringe image 31. The image acquisition condition determination unit 61B determines image acquisition conditions including the photographing conditions of the photographing unit 27 and the image processing conditions of the image processing unit 61A. The photographing conditions include exposure conditions such as the light intensity of the illumination light L.

[0044] The dilution control unit 61C analyzes the cell image 32 reconstructed by the image processing unit 61A to detect the density of cells in the cell suspension 15 in the flow path 29. In other words, the dilution control unit 61C, together with the photographing unit 27 and the image processing unit 61A, constitutes a "density detection mechanism" according to the technology of the present disclosure.

[0045] In the processor 61, the dilution control unit 61C controls the density of the cells 13 by diluting the cell suspension 15 in the flow path 29 using the dilution mechanism 34. Specifically, the dilution control unit 61C compares the measured density detected by the density detection mechanism with a target density that is preset as a density suitable for imaging by the imaging unit 27. If the measured value exceeds the target density, the dilution control unit 61C dilutes the cell suspension 15 to control the density of the cells 13 to the target density.

[0046] The density of the cells 13 is controlled to improve the quality of the cell image 32. In other words, if the exposure amount of the image sensor 27B in the photographing unit 27 is too low, the contrast of the cell image 32 decreases. Here, assuming the same light intensity of the illumination light L, the states of Figures 7 to 9, which have different cell 13 densities, are compared. Figure 7 shows a state where the density of the cells 13 is the target density. In this case, the exposure amount of the image sensor 27B is appropriate, resulting in a cell image 32 with good contrast. In contrast, in the state shown in Figure 8, where the density is higher than in Figure 7, a greater amount of the illumination light L is blocked by the cells 13 in the flow path 29, resulting in a lower exposure amount of the image sensor 27B than in the state shown in Figure 7. Furthermore, in the state shown in Figure 9, multiple cells 13 overlap and aggregate in the flow path 29, forming a cell aggregate 13S. In the state shown in Figure 9, the amount of blocking of the illumination light L is even greater than in the state shown in Figure 8, and the exposure amount of the image sensor 27B is lower than in the state shown in Figure 8. That is, the relationship between the density of the cells 13 and the amount of exposure light is as shown in FIG.

[0047] Therefore, the dilution control unit 61C controls the density of the cells 13 in the cell suspension 15 in the flow path 29 to the target density via the dilution mechanism 34. For example, as shown in FIG. 11 , when the measured density value in the flow path 29 is ρ1 and exceeds the target density ρt, the dilution control unit 61C adds the culture medium 14 to the flow path 29 via the dilution mechanism 34. This controls the density in the flow path 29 to the target density ρt. The target density ρt is a value that is preset as a density suitable for imaging by the imaging unit 27. Specifically, the ideal density is one in which each cell 13 is captured in one interference fringe image 31.

[0048] When the density in the flow channel 29 is maintained at the target density ρt, a decrease in contrast is suppressed in the cell image 32. Since the image quality of the cell image 32 is improved, it becomes possible to grasp the cell quality with high accuracy.

[0049] 8 and 9, if the density of the cells 13 is too high, the number of cells 13 that appear in the interference fringe image 31 will be too large, or multiple cells 13 will appear overlapping each other. In such cases, the image quality of the cell image 32 will be reduced in the sense that it will be difficult to clearly grasp the state of each cell 13. By controlling the density of the cells 13 to a target density, such a reduction in image quality can be suppressed.

[0050] The operation of the above configuration will be described with reference to the flowchart shown in Figure 12. In the cell culture system 2, when culture is started, a cell suspension 15 containing cells 13 is extracted from the culture vessel 16 during the culture. The extracted cell suspension 15 flows through the flow path 29 and is photographed by the photographing unit 27 in step ST100. The processor 61 acquires an interference fringe image 31 of the photographed cells 13. In step ST110, the processor 61 performs image reconstruction processing based on the acquired interference fringe image 31 to reconstruct a cell image 32. In step ST120, the processor 61 outputs the cell image 32 to the display 54.

[0051] The operator checks the cells 13 shown in the displayed cell image 32 and understands the cell quality. Then, depending on the cell quality, the operator determines the process conditions for the culture process and sets the determined process conditions in the culture control device 19. This allows the process conditions to be set and changed depending on the cell quality. As a result, appropriate cell culture is performed. Furthermore, the frequency of monitoring to check the cell quality may be changed depending on the cell quality, such as by increasing the number of times the cell quality is checked if the cell quality does not reach the target.

[0052] Furthermore, in step ST130, the processor 61 of the cell observation device 11 detects the density of the cells 13 in the cell suspension 15 flowing through the flow path 29 by image analysis of the cell image 32. Then, in step ST140, the processor 61 determines whether the measured value of the density of the cells 13 exceeds the target density. If the measured value is equal to or lower than the target density (NO in step ST140), the process proceeds to step ST160. If the measured value exceeds the target density (YES in step ST140), the processor 61 dilutes the density of the cells 13 to the target density through the dilution mechanism 34. This maintains the density of the cells 13 at the target density. In step ST160, the processor 61 determines whether the observation is to be ended, and repeats the above process until the observation is ended.

[0053] The cell observation device 11 according to the technology of the present disclosure includes a photographing unit 27 (an example of a photographing device) that photographs images (e.g., interference fringe images 31) of cells 13 contained in a cell suspension 15 flowing through a flow path 29; a density detection mechanism (e.g., a processor 61) that detects the density of cells 13 in the cell suspension 15; a dilution mechanism 34 that dilutes the cell suspension 15 in the flow path 29; and the processor 61 that dilutes the cell suspension 15 to control the density of cells 13 to a predetermined target density suitable for photographing by the photographing unit 27. Therefore, the exposure amount of the photographing unit 27 is appropriately controlled through control of the density of cells 13, thereby suppressing a decrease in the contrast of the cell image 32. As a result, the cell observation device 11 can acquire cell images 32 with better image quality than conventional methods. Obtaining cell images 32 with good image quality allows for accurate understanding of cell quality, making it possible to determine appropriate process conditions.

[0054] Furthermore, in the above embodiment, the density detection mechanism detects the density by analyzing the cell image 32 obtained through the photographing unit 27. Therefore, a dedicated density detection mechanism separate from the photographing unit 27 is not required.

[0055] Furthermore, in the above embodiment, the cell observation device 11 is equipped with an imaging device (for example, the imaging unit 27) that captures images of the cells 13, and the imaging device is an image measurement device that uses digital holography technology. When an image measurement device that uses digital holography technology is used, the density of the cells 13 may have a relatively large effect on image quality. For this reason, the technology disclosed herein is very effective.

[0056] The photographing unit 27 is disposed in the observation path 22. The flow path 29 of the observation path 22 is extracted from the culture vessel 16 in which the cells 13 are cultured, and is a flow path through which a cell suspension 15 containing the cells 13 in the middle of culture flows. Therefore, it is possible to grasp the state of the cells in the middle of culture, and to control the process conditions of the culture process in the middle of cell culture.

[0057] The flow path 29 of the observation path 22 is a flow path for observing the cells 13 in the middle of culturing, and therefore, unlike the flow path of the culture recovery path 21 through which the cultured cells 13 flow, the range of changes in the cell quality of the cells 13 is wider. Therefore, when observing the cells 13 in the middle of culturing, it is more necessary to accurately grasp the cell quality than when observing the cultured cells 13, and the technology of the present disclosure is particularly effective.

[0058] 13 differs from the first embodiment in that it includes a photosensor 76 that is arranged upstream of the photographing unit 27 in the observation path 22. The rest of the configuration is the same as that of the first embodiment, except for the processing using the photosensor 76.

[0059] The photosensor 76, together with the processor 61, constitutes a density detection mechanism separate from the photographing unit 27. The photosensor 76 is, for example, a transmission-type photosensor in which a light-emitting element 76A and a light-receiving element 76B are arranged opposite each other across the flow path 29 of the observation path 22. As is well known, the photosensor 76 receives detection light emitted by the light-emitting element 76A with the light-receiving element 76B. When an object such as a cell 13 passes between the light-emitting element 76A and the light-receiving element 76B, the object blocks part of the detection light, causing a change in the amount of light received by the light-receiving element 76B. The light-receiving element 76B outputs a detection signal corresponding to the amount of received light to the processor 61. Note that a reflective photosensor may be used as the photosensor 76 instead of a transmission-type photosensor.

[0060] The processor 61 can detect cells 13 passing through the photosensor 76 based on changes in the detection signal corresponding to the amount of light received from the photosensor 76. The processor 61 can then measure the average period of the detection signal, which changes periodically when multiple cells 13 pass through the photosensor 76, to detect the density of multiple cells 13 passing within a certain period of time. The processor 61 can also detect the size of the cell aggregate 13S by measuring the degree and duration of the drop in the detection signal. This is because the drop in the amount of light received by the light-receiving element 76B per unit time is greater and the drop continues for a longer period when a cell aggregate 13S passes than when a single cell 13 passes. For example, the larger the size of the cell aggregate 13S, the higher the density of the cells 13 can be evaluated.

[0061] In this way, the density detection mechanism composed of the photosensor 76 and the processor 61 detects the density of the cells 13 in the section of the flow path 29 upstream of the photographing unit 27. By having such a density detection mechanism, the density detection process can be simplified compared to when the density of the cells 13 is detected by image analysis of the cell image 32.

[0062] (Modification) In the above embodiment, the operator grasps the cell quality based on the cell image 32 output by the cell observation device 11, and determines the process conditions for the culture process based on the grasped cell quality. Such a function may be added to the cell observation device 11.

[0063] 14 , the processor 61 has a function of determining process conditions for a culture process of the cells 13 based on the cell image 32. The processor 61 executes a process condition determination process. In the process condition determination process, the processor 61 determines the cell quality of the cells 13 by performing image analysis on the cell image 32. Based on the determination result, the processor 61 determines the process conditions, including the above-described culture conditions for the cells 13.

[0064] Furthermore, although an image measurement device using digital holography technology has been described as an example of the cell observation device 11, a phase-contrast microscope, a bright-field microscope, or the like may also be used as the cell observation device 11. For example, control of exposure conditions based on flow path information is also effective for phase-contrast microscopes and bright-field microscopes.

[0065] There are various modifications possible to the hardware configuration of the computer that constitutes the cell observation device 11. For example, the cell observation device 11 can be configured with multiple computers separated as hardware, for the purpose of improving processing capacity and reliability.

[0066] In this way, the hardware configuration of the computer of the cell observation device 11 can be changed as appropriate according to the required performance, such as processing power, safety, reliability, etc. Furthermore, not only the hardware, but also application programs such as the operating program 58 can of course be duplicated or stored in a distributed manner across multiple storage devices in order to ensure safety and reliability.

[0067] The above description allows understanding of the technologies described in the following supplementary items. [Supplementary Item 1] A cell observation device comprising: an imaging device that captures images of cells contained in a cell suspension flowing through a flow path; a density detection mechanism that detects the density of cells in the cell suspension; a dilution mechanism that dilutes the cell suspension in the flow path; and a processor that controls the cell density to a target density that is preset as a density suitable for imaging by the imaging device by diluting the cell suspension. [Supplementary Item 2] The cell observation device described in Supplementary Item 1, in which the density detection mechanism detects the density by analyzing images obtained through the imaging device. [Supplementary Item 3] The cell observation device described in Supplementary Item 1 or Supplementary Item 2, in which the imaging device is an image measurement device that uses digital holography technology. [Supplementary Item 4] The cell observation device described in any one of Supplementary Items 1 to 3, in which the density detection mechanism is a mechanism separate from the imaging device and detects the density in a section of the flow path upstream of the imaging device. [Supplementary Item 5] The cell observation device according to any one of Supplementary Items 1 to 4, wherein the processor further has a function of determining process conditions for a cell culture process based on the image. [Supplementary Item 6] The cell observation device according to any one of Supplementary Items 1 to 5, wherein the flow path is a flow path through which a cell suspension extracted from a culture vessel for culturing cells and containing cells in the middle of culture flows. [Supplementary Item 7] A method for operating a cell observation device comprising an imaging device that takes images of cells contained in a cell suspension flowing through the flow path, the method comprising detecting the density of cells in the cell suspension and diluting the cell suspension to control the cell density to a target density that is preset as a density suitable for imaging with the imaging device. [Supplementary Item 8] An operating program for a cell observation device comprising an imaging device that takes images of cells contained in a cell suspension flowing through the flow path and a processor, the operating program causing a processor to execute processes including detecting the density of cells in the cell suspension and diluting the cell suspension to control the cell density to a target density that is preset as a density suitable for imaging with the imaging device.

[0068] In each of the above embodiments, the hardware structure of the processing units that perform various processes, such as the image processing unit 61A, the image acquisition condition determination unit 61B, and the dilution control unit 61C, can be any of the following processors: As described above, the various processors include the CPU 52, which is a general-purpose processor that executes software (operating program 58) to function as various processing units, as well as dedicated electrical circuits that are processors having a circuit configuration specifically designed to perform specific processes, such as a programmable logic device (PLD) that is a processor whose circuit configuration can be changed after manufacture, such as an FPGA (Field Programmable Gate Array), and an ASIC (Application Specific Integrated Circuit).

[0069] A single processing unit may be configured with one of these various processors, or may be configured with a combination of two or more processors of the same or different types (e.g., a combination of multiple FPGAs and / or a combination of a CPU and an FPGA).Furthermore, multiple processing units may be configured with a single processor.

[0070] Examples of configuring multiple processing units with a single processor include, first, a form in which one processor is configured with a combination of one or more CPUs and software, as typified by computers such as client and server, and this processor functions as multiple processing units. Second, a form in which a processor is used to realize the functions of the entire system including multiple processing units with a single IC (Integrated Circuit) chip, as typified by systems on chips (SoCs). In this way, various processing units are configured using one or more of the above-mentioned various processors as a hardware structure.

[0071] Furthermore, more specifically, the hardware structure of these various processors can be an electric circuit (circuitry) that combines circuit elements such as semiconductor elements.

[0072] The technology of the present disclosure can be appropriately combined with the various embodiments and various modifications described above. Furthermore, the technology is not limited to the above embodiments, and various configurations can be adopted as long as they do not deviate from the gist of the present disclosure. Furthermore, the technology of the present disclosure also covers, in addition to programs, storage media that non-temporarily store programs. Examples of storage media include computer-readable non-temporary storage media such as USB (Universal Serial Bus) memory, flexible disks, and CD-ROMs (Compact Disc Read Only Memory). The programs may also be provided online via a network such as the Internet. The technology of the present disclosure also covers, in addition to programs, program products. A program product includes any type of product for providing a program. Like a program, a program product may be provided stored on a computer-readable non-temporary storage medium or provided online.

[0073] The above-described description and illustrations are a detailed explanation of the parts related to the technology of the present disclosure and are merely an example of the technology of the present disclosure. For example, the above description of the configuration, functions, actions, and effects is an explanation of an example of the configuration, functions, actions, and effects of the parts related to the technology of the present disclosure. Therefore, it goes without saying that unnecessary parts may be deleted, new elements may be added, or replacements may be made to the above-described description and illustrations within the scope of the gist of the technology of the present disclosure. Furthermore, to avoid confusion and facilitate understanding of the parts related to the technology of the present disclosure, the above-described description and illustrations omit explanations of common technical knowledge that do not require particular explanation to enable the implementation of the technology of the present disclosure.

[0074] In this specification, "A and / or B" is synonymous with "at least one of A and B." In other words, "A and / or B" means that it may be only A, only B, or a combination of A and B. Furthermore, in this specification, the same concept as "A and / or B" is also applied when three or more things are expressed by connecting them with "and / or."

[0075] The disclosure of Japanese Patent Application No. 2024-026482, filed on February 26, 2024, is incorporated herein by reference in its entirety. In addition, all documents, patent applications, and technical standards described herein are incorporated herein by reference to the same extent as if each individual document, patent application, and technical standard was specifically and individually indicated to be incorporated by reference.

Claims

1. A cell observation device comprising: an imaging device that captures images of cells contained in a cell suspension flowing through a flow path; a density detection mechanism that detects the density of the cells in the cell suspension; a dilution mechanism that dilutes the cell suspension in the flow path; and a processor that dilutes the cell suspension to control the density of the cells to a target density that is preset as a density suitable for imaging by the imaging device.

2. The cell observation device according to claim 1, wherein the density detection mechanism detects the density by analyzing an image obtained through the imaging device.

3. The cell observation device according to claim 1, wherein the imaging device is an image measurement device that uses digital holography technology.

4. The cell observation device according to claim 1, wherein the density detection mechanism is a mechanism separate from the imaging device and detects the density in a section of the flow path upstream of the imaging device.

5. The cell observation device according to claim 1, wherein the processor further has a function of determining process conditions for the cell culture process based on the image.

6. The cell observation device according to claim 1, wherein the flow path is extracted from a culture vessel in which the cells are cultured, and is a flow path through which the cell suspension containing cells in the middle of culture flows.

7. A method for operating a cell observation device equipped with an imaging device that takes images of cells contained in a cell suspension flowing through a flow path, the method comprising detecting the density of cells in the cell suspension and diluting the cell suspension to control the density of the cells to a target density that is preset as a density suitable for imaging by the imaging device.

8. An operating program for a cell observation device comprising a processor and an imaging device that captures images of cells contained in a cell suspension flowing through a flow path, the operating program causing the processor to execute processes including: detecting the density of cells in the cell suspension; and diluting the cell suspension to control the density of the cells to a target density that is preset as a density suitable for imaging by the imaging device.

Images