Patent Application
20240141289
The present invention relates to a method for constructing a human pluripotent stem cell-derived liver organoid having enhanced drug metabolic potentials and a liver organoid constructed by the method.
The liver is a central organ of metabolic and physiological homeostasis with diverse functions such as metabolism, protein synthesis, bile production, and red blood cell removal. Hepatocytes, the hepatic parenchymal cells, are primarily responsible for maintaining liver homeostasis and are therefore the target of many diseases. Despite recent technological advances in disease modeling of liver failure, there is a need for models of congenital and progressive metabolic diseases that can lead to the end-stage of liver failure. Furthermore, since the liver has a specific function for the detoxification of pharmaceuticals, a model that mimics human hepatocytes is required as a tool for evaluating drug metabolism and toxicity in drug development. Although current in vitro and in vivo liver models have contributed greatly to elucidating the pathogenesis of liver diseases and evaluating drug stability, they still have limitations that do not fully reflect the physiology of the human liver. Animal models have limitations in predicting drug toxicity due to interspecies differences. In addition, primary human hepatocytes (PHH) are the standard in vitro liver model, but they have limited accessibility to the human liver tissue and unstable function. Also, liver cancer cell lines are not normal cells, so their drug metabolism enzymes are not fully expressed or their function is reduced. Therefore, they are not suitable for evaluating drug toxicity. Thus, it is necessary to construct a liver model that can mimic human liver metabolism and has drug metabolism capability.
An organoid is an organ-specific cell aggregate made by three-dimensional cultivation, aggregation, or recombination of stem cells that is capable of self-renewal and is sometimes referred to as a “mini-organ” or “pseudo-organ. Organoids are very useful for basic research as they allow research that is difficult to implement in animal models, such as molecular signal regulation, to be performed in vitro in a form similar to the actual organ, and can be used in various fields such as human development process, disease model establishment, drug efficacy evaluation screening, development of drug toxicity evaluation platform, and development of cell therapy.
A human liver organoid was first developed from adult human liver tissue using a culture medium containing R-Spondin 1. Primary human hepatocytes (PHH) were also applied to 3D organoid culture, and the generation of liver buds and liver organoids from human pluripotent stem cells (hPSC) was reported. Human pluripotent stem cell-derived liver organoids (hHO) have been proposed as in vitro models for disease modeling such as genetic and metabolic disorders, cell therapy and drug toxicity testing.
Currently, research for the establishment of various organoids has been conducted, and liver organoids have also been developed. Prior art related to a method for constructing a liver organoid includes the following references: Literatures confirmed that liver organoids were generated through an expansion step derived from definitive endoderm and hepatic endoderm, the generated liver organoids were capable of proliferation, and they enabled modeling of citrullinemia type 1 and alcoholic liver injury (Akbari et al. (2019). Robust, Long-Term Culture of Endoderm-Derived Hepatic Organoids for Disease Modeling. Stem Cell Reports 13, 627-641., Wang et al. (2019). Human ESC-derived expandable hepatic organoids enable therapeutic liver repopulation and pathophysiological modeling of alcoholic liver injury. Cell Res 29, 1009-1026.), A literature producing liver organoids through an expansion step derived from 3D spherical hPSC-derived mature hepatocyte-like cells (HLC), and proposing the liver organoids as a model to evaluate drug-induced hepatic steatosis (Mun et al. (2019). Generation of expandable human pluripotent stem cell-derived hepatocyte-like liver organoids. J Hepatol 71, 970-985.), and U.S. Pat. No. 8,642,339B2, which discloses a method for generating organoids by collecting human hepatocytes and isolating stem cells therefrom.
However, liver organoids known so far have limitations in reproducing drug metabolism and transport functions. As an in vitro model for drug toxicity and efficacy testing, liver organoids should be reproducibly produced and should exhibit drug metabolism and transport functions similar to those of adult liver and primary human hepatocytes (PHH). To this end, it is necessary to construct a liver organoid expressing the liver cytochrome P450 (CYP450) protein, which is a superfamily enzyme mainly responsible for the biotransformation of most pharmaceuticals and xenobiotics. It is necessary to develop a liver organoid that can function as a toxicity screening platform through detailed functional analysis such as drug metabolism and transport.
Accordingly, the present inventors found that when the liver organoids were constructed by culturing in a medium without R spondin-1, Noggin, and EGF, or selectively culturing in a medium containing iron ions, the expression and function of drug metabolism enzymes were excellent, and they exhibited drug-induced toxicity, and completed the present invention.
It is an object of the present invention to provide a method for constructing a liver organoid having enhanced drug metabolic potentials and a liver organoid constructed by the method.
To achieve the above object, the present invention provides a method for constructing a liver organoid comprising the following steps:
In addition, the present invention provides a liver organoid having enhanced drug metabolic capability constructed by the method.
The present invention relates to a method for constructing a human pluripotent stem cell-derived liver organoid having enhanced drug metabolic potentials and a liver organoid constructed by the method. Because differentiation is made from human induced pluripotent stem cells dedifferentiated from somatic cells of patients, the cells are easily supplied so that patient-specific liver organoids can be prepared. The organoids can similarly simulate the real human liver structure because they consist of hepatocytes, cholangiocytes, gallbladder cells, and microduct structures, have excellent expression and functions of drug metabolism enzymes, and exhibit drug toxicity, drug metabolic capability, and drug-induced cardiotoxicity. Thus, the organoids can be advantageously used as liver models for searching for pathogenesis of liver diseases and for evaluating drug stability.
Hereinafter, the present invention is described in detail.
The present invention provides a method for constructing a liver organoid comprising the following steps:
The human pluripotent stem cells may be human embryonic stem cells (hESCs) or human induced pluripotent stem cells (hiPSCs), and may be of human origin, but not always limited thereto.
If it is confirmed by flow cytometry that the hepatic endoderm cells in step 2) are more than 95% of the total cells, proceed to step 3).
The differentiation may be to differentiate stem cells in a culture vessel coated with Matrigel to simulate the microenvironment of cells, but not always limited thereto, and a culture vessel coated with fibronectin or laminin can be used.
The hepatic endoderm organoid can be constructed in the form of droplet or in suspension.
The hepatic endoderm organoid of step 3) can be cryopreserved and thawed.
The droplet-shaped hepatic endoderm organoid can be constructed by mixing hepatic endoderm cells with Matrigel GFR (growth factor reduced) stock solution, dispensing the mixture into a dome structure in a well plate, and solidifying thereof.
The suspension-type hepatic endoderm organoid can be constructed by adding hepatic endoderm cells to a well plate containing a medium comprising Matrigel GFR (growth factor reduced).
The differentiation of step 3) consists of a generation stage and an expansion stage.
The generation stage is conducted in a hepatic endoderm organoid production medium (GE medium, GM).
The hepatic endoderm organoid production medium contains fibroblast growth factor 10 (FGF10), hepatocyte growth factor (HGF), nicotinamide, [Leu15]-Gastrin I human, N-acetyl-L-cysteine, A83-01, Forskolin and CHIR99021, and can optionally include Matrigel GFR (growth factor reduced) when preparing organoids in suspension.
The FGF10 can be included in the medium at 30 to 70 ng/m, preferably at 40 to 60 ng/m
, or more preferably at 45 to 55 ng/m
.
The HGF can be included in the medium at 5 to 45 ng/m, preferably at 15 to 35 ng/m
, or more preferably at 20 to 30 ng/m
.
The nicotinamide can be included in the medium at 1 to 20 mM, preferably at 5 to 15 mM, or more preferably at 7 to 13 mM.
The [Leu15]-Gastrin I human can be included in the medium at 1 to 20 nM, preferably at 5 to 15 nM, or more preferably at 7 to 13 nM.
The N-acetyl-L-cysteine can be included in the medium at 0.25 to 2.25 mM, preferably at 0.5 to 2 mM, or more preferably at 1 to 1.5 mM.
The A83-01 can be included in the medium at 1 to 9 μM, preferably at 3 to 7 μM, or more preferably at 4 to 6 μM.
The Forskolin can be included in the medium at 5 to 15 μM, preferably at 7 to 13 μM, or more preferably at 8 to 12 μM.
The CHIR 99021 can be included in the medium at 1 to 5 μM, preferably at 2 to 4 μM, or more preferably at 2.5 to 3.5 μM.
The Matrigel GFR can be included in the medium at 0.2 to 0.8 mg/m, preferably at 0.3 to 0.7 mg/m
, or more preferably at 0.4 to 0.6 mg/m
.
The generation stage can be performed for 10 to 18 days, preferably 12 to 16 days, and more preferably 13 to 15 days.
The expansion stage is conducted in a medium with the same composition as the hepatic endoderm organoid production medium used in the generation stage.
The expansion stage can be performed for 3 to 7 days, and preferably can be performed for 4 to 6 days.
Compared to the composition of the medium used in the conventional liver organoid culture method (Hugh et al., Long-Term Culture of Genome-Stable Bipotent Stem Cells from Adult Human Liver, Cell (2015)), the medium used in the generation stage during the differentiation of hepatic endoderm cells into hepatic endoderm organoids does not contain R spondin-1, Noggin, and EGF, and the medium used in the expansion stage does not include R spondin-1 and EGF.
The step of differentiating hepatic endoderm cells into hepatic endoderm organoids can be performed for 13 to 25 days, preferably for 15 to 23 days, and more preferably for 17 to 21 days.
The step of differentiating the hepatic endoderm organoid into the liver organoid in step 4) can be performed in a medium containing iron ions.
The medium containing iron ions may be a medium comprising any one selected from the group consisting of ferric citrate (FC), iron chloride (FeCl3), iron sulfate (Fe2SO4), ferric sulfate (Fe2(SO4)3), iron nitrate (Fe(NO3)3), and pentacarbonyl iron (Fe(CO)5), but not always limited thereto.
The ferric citrate can be included at a concentration of 10 to 30 μM, and preferably at a concentration of 15 to 25 μM.
The liver organoid of step 4) can be constructed in the form of droplet or in suspension.
The liver organoid includes biliary-like cells, gallbladder-like cells, and hepatocyte-like cells. The differentiation of step 4) comprises a step of subculturing a hepatic endoderm organoid and a step of differentiating the hepatic endoderm organoid into a liver organoid.
The droplet-shaped liver organoid is constructed by performing a step of subculturing a droplet-shaped hepatic endoderm organoid and a step of differentiating the droplet-shaped hepatic endoderm organoid into a liver organoid.
The suspension-type liver organoid is constructed by performing a step of subculturing a suspension-type hepatic endoderm organoid and a step of differentiating the suspension-type hepatic endoderm organoid into a liver organoid.
The step of subculturing a hepatic endoderm organoid is performed in a hepatic endoderm organoid expansion medium (EM).
The hepatic endoderm organoid expansion medium contains bone morphogenetic protein 7 (BMP7), fibroblast growth factor 10 (FGF10), hepatocyte growth factor (HGF), nicotinamide, [Leu15]-Gastrin I human, N-acetyl-L-cysteine, A83-01, Forskolin and CHIR99021, and can optionally include Matrigel GFR (growth factor reduced) when preparing liver organoids in suspension.
The BMP7 can be included in the medium at 5 to 45 ng/m, preferably at 15 to 35 ng/m
, or more preferably at 20 to 30 ng/m
.
The FGF10 can be included in the medium at 30 to 70 ng/m, preferably at 40 to 60 ng/m
, or more preferably at 45 to 55 ng/m
.
The HGF can be included in the medium at 5 to 45 ng/m, preferably at 15 to 35 ng/m
, or more preferably at 20 to 30 ng/m
.
The nicotinamide can be included in the medium at 1 to 20 mM, preferably at 5 to 15 mM, or more preferably at 7 to 13 mM.
The [Leu15]-Gastrin I human can be included in the medium at 1 to 20 nM, preferably at 5 to 15 nM, or more preferably at 7 to 13 nM.
The N-acetyl-L-cysteine can be included in the medium at 0.25 to 2.25 mM, preferably at 0.5 to 2 mM, or more preferably at 1 to 1.5 mM.
The A83-01 can be included in the medium at 1 to 9 μM, preferably at 3 to 7 μM, or more preferably at 4 to 6 μM.
The Forskolin can be included in the medium at 5 to 15 μM, preferably at 7 to 13 μM, or more preferably at 8 to 12 μM.
The CHIR99021 can be included in the medium at 1 to 5 μM, preferably at 2 to 4 μM, or more preferably at 2.5 to 3.5 μM.
The Matrigel GFR can be included in the medium at 0.2 to 0.8 mg/m, preferably at 0.3 to 0.7 mg/m
, or more preferably at 0.4 to 0.6 mg/m
.
The step of subculturing a hepatic endoderm organoid can be performed for 2 to 8 days, preferably for 3 to 7 days, and more preferably for 4 to 6 days.
The step of differentiating the hepatic endoderm organoid into a liver organoid is performed in a liver organoid differentiation medium (DM).
The liver organoid differentiation medium contains bone morphogenetic protein 7 (BMP7), fibroblast growth factor 19 (FGF19), hepatocyte growth factor (HGF), [Leu15]-Gastrin I human, N-acetyl-L-cysteine, A83-01, DAPT and dexamethasone, and can optionally include Matrigel GFR (growth factor reduced) when preparing liver organoids in suspension. In addition, to further enhance the drug metabolic capability, ferric citrate (FC) can be further included in the medium.
The BMP7 can be included in the medium at 5 to 45 ng/m, preferably at 15 to 35 ng/m
, or more preferably at 20 to 30 ng/m
.
The FGF19 can be included in the medium at 50 to 150 ng/m, preferably at 70 to 130 ng/m
, or more preferably at 90 to 110 ng/m
.
The HGF can be included in the medium at 5 to 45 ng/m, preferably at 15 to 35 ng/m
, or more preferably at 20 to 30 ng/m
.
The [Leu15]-Gastrin I human can be included in the medium at 1 to 20 nM, preferably at 5 to 15 nM, or more preferably at 7 to 13 nM.
The N-acetyl-L-cysteine can be included in the medium at 0.25 to 2.25 mM, preferably at 0.5 to 2 mM, or more preferably at 1 to 1.5 mM.
The A83-01 can be included in the medium at 0.1 to 0.9 μM, preferably at 0.2 to 0.8 μM, or more preferably at 0.4 to 0.6 μM.
The DAPT can be included in the medium at 0.2 to 1.8 μ, preferably at 0.5 to 1.5 μ
, or more preferably at 0.8 to 1.2 μ
.
The dexamethasone can be included in the medium at 1 to 5 μM, preferably at 2 to 4 μM, or more preferably at 2.5 to 3.5 μM.
The Matrigel GFR can be included in the medium at 0.2 to 0.8 mg/m, preferably at 0.3 to 0.7 mg/m
, or more preferably at 0.4 to 0.6 mg/m
.
The ferric citrate can be included in the medium at a concentration of 10 to 30 μM, and preferably at a concentration of 15 to 25 μM.
The step of differentiating the hepatic endoderm organoid into a liver organoid can be performed for 10 to 20 days, preferably for 12 to 18 days, and more preferably for 13 to 17 days.
In addition, R spondin-1 and EGF are not included in the step of subculturing a hepatic endoderm organoid, and EGF is not included in the step of differentiating the hepatic endoderm organoid into a liver organoid during the step of differentiating the hepatic endoderm organoid into the liver organoid compared to the conventional culture method.
In conclusion, in the step of differentiating into a hepatic endoderm organoid, culturing in a culture medium that does not contain R-spondin 1, Noggin and EGF has an effect on the stage of organoid maturation, and in the step of differentiating into a liver organoid, removal of R-spondin 1 and EGF from the culture medium promotes the liver organoid maturation by increasing the expression the levels of genes involved in liver and drug metabolism.
The differentiation in step 4) can be performed for 10 to 30 days, preferably for 13 to 27 days, and more preferably for 15 to 25 days.
In addition, the present invention provides a liver organoid having enhanced drug metabolic capability constructed by the method for constructing a liver organoid above.
The liver organoid expresses cytochrome P450 (CYP450) at a high level.
Cytochrome P450 (CYP450) is a superfamily of enzymes having heme as a prosthetic group and is known as a representative catalytic enzyme that performs oxidative metabolism on various exogenous substances such as most drugs and environmental materials or endogenous substances such as steroids and lipids. CYP450 enzymes get their name from the fact that the iron ions contained in heme exhibit a specific absorbance spectrum at 450 nm when bound to carbon monoxide in a reduced state.
The primary function of CYP450 enzymes is mono-oxygenation (mixed-function oxidase reaction) on a variety of substrates, which requires oxygen molecules and NADPH reducing substances. One atom of the oxygen molecule binds to the substrate being oxidized and the other atom is reduced to water. In the microsomal CYP450 system, which is abundant in hepatocytes, CYP450 enzymes are located in the membrane of the endoplasmic reticulum and receive electrons from the NADPH-P450 reductase coexisting in the membrane to perform oxidation reaction.
The cytochrome P450 is at least one selected from the group consisting of CYP1A2, CYP2C9, CYP2C19, CYP2D6, and CYP3A4.
CYP1A2, CYP2C9, CYP2C19, CYP2D6, and CYP3A4 are types of cytochrome P450, and have a function of primarily metabolizing 95% of drugs in use.
In addition, the liver organoid can be used to evaluate the drug-induced toxicity.
Furthermore, the liver organoid can be used to evaluate the drug-induced cardiotoxicity.
In specific embodiments of the present invention, it was confirmed that Wnt signaling was not required in the step of differentiating a hepatic endoderm organoid from hepatic endoderm cells (
Therefore, the organoids constructed by the present invention can be advantageously used as liver models for searching for pathogenesis of liver diseases and for evaluating drug stability.
Hereinafter, the present invention will be described in detail by the following examples and experimental examples.
However, the following examples and experimental examples are only for illustrating the present invention, and the contents of the present invention are not limited thereto.
First, vitronectin XF (Cat*.07180, Stem cell technologies) was added to a cell culture plate to coat the wells of the plate. Human induced pluripotent stem cells (hiPSCs) (provided by Dr. Yongman Han, KAIST) derived from human dermal fibroblasts through ectopic expression of OCT4, SOX2, KLF4 and c-MYC were cultured with mTeSR™-E8™ medium (Cat*. 05940, Stem cell technologies) on the coated plate under 37° C., 5% CO2 conditions. hiPSCs were subcultured every 3 or 4 days with dissociation using Ca2+/Mg2+ free Dulbecco's phosphate-buffered saline (DPBS)supplemented with 0.5 mM EDTA. At this time, the medium was replaced every day during the subculture period.
Diluted Matrigel (hESC qualified Matrigel, Corning, Cat No. 354277) was added to a 12-well plate (0.5 m per well), and the plate was coated with Matrigel at 37° C. for 30 minutes. Then, the cultured human induced pluripotent stem cells were taken out, the medium was removed, and 1 m
of Ca2+/Mg2+ free DPBS supplemented with 0.5 mM EDTA was added to each well of the plate, followed by culture at 37° C. for 4 to 5 minutes. EDTA was removed by tilting the plate, and the cells were recovered using 1 m
of 12 m
of mTeSR™-E8™ medium containing 2 μM of Y27632. The recovered cells were placed in a conical tube containing 11 m
of mTeSR™-E8™ medium containing 2 μM Y27632 and mixed by gentle pipetting. The recovered cells were dispensed in a plate coated with Matrigel (1 m
per well) and cultured for one day at 37° C., 5% CO2 conditions, and human induced pluripotent stem cells were seeded in a plate coated with Matrigel.
To differentiate the human induced pluripotent stem cells cultured in Examples <1-1> into definitive endoderm cells, the following procedure was performed.
Specifically, 12 m of the endodermal differentiation medium 1 (DE medium 1) with the composition of Table 1 below was made to 37° C., and then the medium was added to the plate containing the human induced pluripotent stem cells cultured in Example <1-1> (1 m
per well), followed by culture in a 37° C., 5% CO2 incubator for 24 hours. Then, the medium was replaced with the endoderm differentiation medium 2 (DE medium 2) with the composition of Table 2, and cultured in a 37° C., 5% CO2 incubator for 4 days. During the culture period, the medium was replaced every 24 hours.
)
Activin A (ActA)
Activin A (ActA)
To differentiate the definitive endoderm cells differentiated in Examples <1-2> into hepatic endoderm cells, the following procedure was performed.
Specifically, 12 m of the hepatic endoderm differentiation medium (HE medium) with the composition of Table 3 below was made to 37° C., and then the medium was added to the plate containing the definitive endoderm cells differentiated in Example <1-2> (1 m
per well), followed by culture in a 37° C., 5% CO2 incubator for 4 days. During the culture period, the medium was replaced every 24 hours. After completion of the differentiation, EpCAM-positive cells in some cells were analyzed under the same conditions and methods as the flow cytometry described in Experimental Example 1 below, and if the EpCAM-positive cells were more than 95%, the next step, the hepatic endoderm organoid production step, was performed.
)
BMP 4
After the differentiation was completed, the medium was removed from the hepatic endoderm cells prepared in Example <1-3>. The cells were washed once with Ca2+/Mg2+-free DPBS, and 500 μ of accutase was added to each well, followed by culture at 37° C. for 10 minutes. The cells separated into single cells were transferred to a 15 m
conical tube containing 10 m
of an organoid basal medium (advanced DMEM/F12 containing 10 mM HEPES, 1% GlutaMAX, 100 U/m
penicillin-streptomycin, and 0.1% BSA), centrifuged at 1200 rpm for 3 minutes, and the obtained supernatant was removed. The cell pellet was resuspended in 1 m
of a cold hepatic endoderm production medium for D-HEO or S-HEO (Table 4 or 5), transferred to a 1.5 m
tube for cell counting, and hepatic endoderm organoids were produced in the form of droplet or in suspension as follows.
15,000 hepatic endoderm cells in 100 μ of a cold hepatic endoderm organoid production medium with the composition of Table 4 were prepared in a 1.5 m
tube and placed on ice. 200 μ
of Matrigel GFR (growth factor reduced) stock solution was added to the prepared cells and mixed by pipetting to avoid the formation of bubbles. A mixture of 100 μ
of Matrigel and hepatic endoderm cells in a 24-well or 4-well plate was made at a cell density of 5000 cells/droplet and dispensed in the center of the plate to form a dome structure and solidified at 37° C. for 10 minutes. Then, 700 to 1000 μ
of a 37° C. hepatic endoderm organoid production medium at was added to each well of the plate and cultured for 14 days in a 37° C., 5% CO2 incubator.
penicillin-streptomycin, 0.1% BSA,
FGF 10 (fibroblast growth factor 10)
HGF (hepatocyte growth factor)
A hepatic endoderm organoid production medium with the composition of Table 5 was pre-dispensed in a 24-well ultra low attachment plate (0.5 m per well). The medium was always kept on ice to prevent the Matrigel from solidifying. After adding 10,000 hepatic endoderm cells to each well of the plate, the cells were cultured for 14 days in a 37° C., 5% CO2 incubator. At this time, the pieces were spread evenly and cultured to prevent the organoids from clumping and growing. The medium was replaced every 3 days of culture. To replace the medium, all medium containing organoids cultured in suspension was collected in a 1.5 m
tube using a 1000 P pipette and centrifuged at 1200 rpm for 3 minutes to remove the supernatant. The cell pellet was resuspended in 0.5 m
of a new hepatic endoderm expansion medium with the composition of Table 5, and the cells were seeded in a plate, followed by culture in a 37° C., 5% CO2 incubator for 3 days.
penicillin-streptomycin, 0.1% BSA,
FGF 10 (fibroblast growth factor 10)
HGF (hepatocyte growth factor)
Matrigel GFR (growth factor reduced)
The hepatic endoderm organoids prepared in Examples <1-4-1> and <1-4-2> were further cultured for 5 days in a medium having the composition of Table 4 or Table 5, respectively, to finally construct droplet-shaped hepatic endoderm organoids (D-HEO) (
The droplet-shaped hepatic endoderm organoids (D-HEO) were taken out of the incubator and pipetted with a 1000 P pipette to break the dome-shaped Matrigel containing the organoids, and then collected in a 1.5 m tube.
The suspension-type hepatic endoderm organoids (S-HEO) were taken out of the incubator and pipetted with a 1000 P pipette to collect all of the organoids including the medium in the wells in a 1.5 m tube.
In order to separate the hepatic endoderm organoids and Matrigel, the tube was placed on ice for 30 minutes and centrifuged at a maximum speed of 5000 rpm to remove the supernatant. 200 μ of a cold hepatic endoderm organoid expansion medium for D-HEO or S-HEO was added thereto, and the organoids were fragmented by pipetting with a 200 P pipette. Then, centrifugation was performed at a maximum speed of 5000 rpm to remove the supernatant, and after adding 1 m
of cold DPBS without Ca2+ and Mg2+, centrifugation was performed at a maximum speed of 5000 rpm to remove the supernatant again. After resuspension with 1 to 1.5 m
of CryoStor CS10 (Stem cell Technologies), the cryoprotectant, and the suspension was dispensed into cryotubes (0.5 m
/tube). The cryotubes were placed in a freezing container, stored in a deep freezer for one day, and transferred to a LN2 tank (nitrogen tank) the next day.
One cryotube was taken out of the LN2 tank and thawed in a 37° C. water bath, and when it was half melted, it was taken out of the water bath and transferred to a 15 m conical tube containing 10 m
of an organoid basal medium (advanced DMEM/F12 containing 10 mM HEPES, 1% GlutaMAX, 100 U/m
penicillin-streptomycin, and 0.1% BSA) prepared in advance and centrifuged at 1000 rpm for 3 minutes to remove the supernatant.
In the case of the droplet-shaped hepatic endoderm organoids (D-HEO), the organoid pellet was resuspended in 100 μ of a cold hepatic endoderm organoid expansion medium (Table 6), and then 200 μ
of Matrigel GFR stock solution was added, followed by mixing. Thereafter, 100 μ
of a mixture of the hepatic endoderm organoids and Matrigel was dispensed in the center of each well of a new 24-well plate to form a dome shape and solidified at 37° C. for 10 minutes. 700 to 1000 μ
of a hepatic endoderm organoid expansion medium containing 20 μM Y27632 (Table 6) at 37° C. was added to each well and cultured in a 37° C., 5% CO2 incubator for 3 to 4 days.
In the case of the suspension-type hepatic endoderm organoids (S-HEO), the organoid pellet was resuspended in 1 to 1.5 m of a cold hepatic endoderm organoid expansion medium (Table 7), and then 0.5 m
of the suspension was added to each well of a new 24-well ultra-low attachment plate, followed by culture in a 37° C., 5% CO2 incubator for 3 to 4 days. At this time, the pieces were spread evenly and cultured to prevent the organoids from clumping and growing. The medium was replaced every 3 days of culture.
Primary human hepatocytes (PHH), HepG2 (liver cancer cell line), and 2D hPSC-derived hepatocyte-like cells (HLC) were cultured as follows.
As the primary human hepatocytes (PHH), BD Gentestm Cryo Human Hepatocytes (BD Biosciences, Donor No. HFC 476) were cultured in a BD™ hepatocyte culture medium according to the manufacturer's instructions, and experiments were performed 24 hours later.
The liver cancer cell line HepG2 was maintained in MEM (HyClone) supplemented with 10% fetal bovine serum (Lonza) and 100 U/m penicillin-streptomycin (Gibco).
In the case of the 2D hPSC-derived hepatocyte-like cells (HLC), hPSC-derived hepatic endoderm (HE) cells were further cultured in RPMI-1640 supplemented with 0.5 mg/m BSA, 1× B27, 10 ng/m
FGF4, 10 ng/m
HGF, 10 ng/m
OSM, and 0.1 μM dexamethasone for 7 days.
The hepatic endoderm organoids constructed in Example <1-5> were subcultured and differentiated in a differentiation medium to prepare liver organoids (human hepatic organoids, hHOs) in the following manner.
The droplet-shaped hepatic endoderm organoids (D-HEO) constructed in Example <1-5> were pipetted with a 1000 P pipette to break the dome-shaped Matrigel containing the organoids, and then collected in a 1.5 m tube. To separate the Matrigel and hepatic endoderm organoids, the tube was placed on ice for 30 minutes. The tube was centrifuged at a maximum speed of 5000 rpm to remove the supernatant, and 200 μ
of a cold hepatic endodermal organoid expansion medium (EM) with the composition of Table 6 was added thereto, and pipetting was performed several times with a 200 P pipette to fragment organoids. Thereafter, the tube was centrifuged at a maximum speed of 5000 rpm to remove the supernatant, and 140 μ
of a cold hepatic endodermal organoid expansion medium and 280 μ
of Matrigel GFR stock solution were, followed by mixing. Then, 100 μ
of a mixture of the hepatic endoderm organoids and Matrigel was dispensed in the center of each well of a new 24-well plate to form a dome shape and solidified at 37° C. for 10 minutes. 700 to 1000 μ
of a hepatic endoderm organoid expansion medium at 37° C. was added to each well and cultured in a 37° C., 5% CO2 incubator for 5 days.
penicillin-streptomycin, 0.1% BSA,
BMP7
FGF 10 (fibroblast growth factor 10)
HGF (hepatocyte growth factor)
The suspension-type hepatic endoderm organoids (S-HEO) constructed in Example <1-5> were cultured in a hepatic endoderm organoid production medium with the composition of Table 7 supplemented with 25 ng/m of BMP7 for 5 days. At this time, the medium was replaced once after 3 days of culture.
The suspension-type hepatic endoderm organoids (S-HEO) constructed in Example <1-5> were collected in a 1.5 m tube using a 1000 P pipette, and the tube was placed on ice for 30 min to separate the hepatic endoderm organoids and Matrigel. The tube was centrifuged at a maximum speed of 5000 rpm to remove the supernatant. 200 μ
of a cold hepatic endoderm organoid expansion medium (EM) with the composition of Table 7 was added thereto, and the organoids were fragmented by pipetting with a 200 P pipette. 0.5 m
of a hepatic endoderm organoid expansion medium with the composition of Table 7 was pre-dispensed into each well of a new 24-well ultra-low attatchment plate, and 66 μ
of the fragmented hepatic endoderm organoid (S-HEO) suspension was dispensed into each well of the plate, followed by culture in a 37° C., 5% CO2 incubator for 5 days. At this time, the pieces were spread evenly and cultured to prevent the organoids from clumping and growing. The medium was replaced every 3 days of culture. To replace the medium, all medium containing organoids cultured in suspension was collected in a 1.5 m
tube using a 1000 P pipette and centrifuged at 5000 rpm to remove the supernatant. The pellet was resuspended in 0.5 m
of a new hepatic endoderm expansion medium, and the cells were seeded in a plate.
penicillin-streptomycin, 0.1% BSA,
BMP7
FGF 10 (fibroblast growth factor 10)
HGF (hepatocyte growth factor)
Matrigel GFR (growth factor reduced)
The droplet-shaped hepatic endoderm organoids subcultured in Example <2-1-1> were cultured for 15 days using a liver organoid differentiation medium with the composition of Table 8. At this time, the medium was replaced every 3 days of culture.
penicillin-streptomycin, 0.1% BSA,
BMP7
FGF19
HGF
DAPT
The suspension-type hepatic endoderm organoids subcultured in Example <2-1-2> were cultured for 15 days using a liver organoid differentiation medium with the composition of Table 9. At this time, the medium was replaced every 3 days of culture.
To replace the medium, all medium containing liver organoids cultured in suspension was collected in a 1.5 m tube using a 1000 P pipette and centrifuged at 5000 rpm to remove the supernatant. The pellet was resuspended in 0.5 m
of a new hepatic organoid differentiation medium, and the cells were seeded in a plate.
penicillin-streptomycin, 0.1% BSA,
BMP7
FGF19
HGF
DAPT
Matrigel GFR (growth factor reduced)
To determine the composition of a hepatic endoderm organoid production medium, the following experiment was performed.
Specifically, except that cultured in a medium further containing R-Spondin 1, EGF, and Noggin in the medium composition of Table 4, hepatic endoderm organoids were differentiated by the same methods and conditions as in Examples <1-4-1>, and hepatic endoderm organoids were developed using a hepatic endoderm organoid expansion medium (EM) with the composition of Table 6. The number of cells expressing EpCAM in hepatic endoderm cells and hepatic endoderm organoids was analyzed by flow cytometry, and the expression levels of LGR5, a target protein of Wnt, and the target genes AXIN2 and EPHB2 were measured by RT-qPCR.
Flow cytometry was performed by dissociating cells or organoids with TypLE™ Express Enzyme (Thermo), fixing with 4% formaldehyde, and permeabilizing with 0.1% Triton X-100 in DPBS (HyClone™). The sample was incubated with a fluorescently labeled primary antibody on ice for 10 minutes and then washed twice with 0.5% BSA (Sigma) in DPBS. Flow cytometry was performed using CytoFLEX (Beckman Coulter), and data were processed using Kaluza analysis software (Beckman Coulter).
Quantitative reverse transcriptase polymerase chain reaction (RT-qPCR) using NucleoZOL Reagent (Macherey-Nagel, Duren, Germany) was performed to isolate total RNA from each sample and reverse transcribed using GoScript™ Reverse Transcription Mix (Promega). The qPCR was performed using GoTaq® qPCR Master Mix (Promega) in StepOnePlus Real-Time PCR system (Applied Biosystems, Foster City, CA, USA), and triplicate PCR amplifications were performed for each sample. PCR results were expressed as fold change relative to control cells after normalization with glyceraldehyde-3-phosphate dehydrogenase (GAPDH). The ΔCt (SΔCt) value was calculated as the difference between the Ct value obtained for GAPDH and the target gene. The ΔCt value of the control cell was used as the control ΔCt (SΔCt) value. The relative gene expression levels were determined using formula 2—(SΔCt−CΔCt).
As a result, as shown in
These results suggest that Wnt signaling is not required for hepatic endoderm organoid development. Furthermore, since R-Spondin 1, EGF, and Noggin are known to be key factors in intestinal organoid production and expansion, and Noggin, a BMP antagonist, is known to inhibit liver specification, hepatic endoderm organoids were differentiated with a medium composition excluding R-Spondin 1, EGF, and Noggin.
In the case of differentiation into hepatic endoderm organoids by culturing in a medium further containing R-Spondin 1, EGF, and Noggin in the medium composition of Table 4, and differentiation into hepatic endoderm organoids under the same methods and conditions as in Example <1-4-1>, the number of organoids and the rate of organoid formation were measured.
As a result, as shown in
In the case of cultivation of droplet-shaped hepatic endoderm organoids in the hepatic endoderm organoid expansion medium containing R-Spondin 1 and EGF (RE) (D(+)-HEO), in the case of cultivation of droplet-shaped hepatic endoderm organoids in the hepatic endoderm organoid expansion medium without R-Spondin 1 and EGF (RE) (D(−)-HEO), in the case of cultivation of suspension-type hepatic endoderm organoids in the hepatic endoderm organoid expansion medium containing R-Spondin 1 and EGF (RE) (S(+)-HEO), and in the case of cultivation of suspension-type hepatic endoderm organoids in the hepatic endoderm organoid expansion medium without R-Spondin 1 and EGF (RNE) (S(−)-HEO), the proliferative capacity of the hepatic endoderm organoids and the expression of the hepatic progenitor cell markers were measured and transcriptome analysis was performed.
In the hepatic endoderm organoids cultured under the four conditions of D(+)-HEO, D(−)-HEO, S(+)-HEO and S(−)-HEO, the organoid structure, the presence of proliferating cells, and the expression of SOX9 and EpCAM, the hepatic endoderm cell markers, were investigated as follows.
Specifically, the hepatic endoderm organoids differentiated under the four conditions were imaged by bright-field microscopy, and the paraffin-embedded sections of the hepatic endoderm organoids differentiated under each condition were stained with Hematoxylin & Eosin (H & E).
For BrdU staining, hepatic endoderm organoids (hHEO) were treated with 10 pM bromo-deoxyuridine (BrdU) labeling solution (Molecular Probes, Eugene, OR, USA) and cultured in a 37° C., 5% CO2 incubator for 48 hours. Hepatic endoderm organoids (hHEO) were isolated, fixed, permeabilized, denatured with 1.2 M HCl, and stained with BrdU monoclonal antibody and Alexa Flour 488 (Invitrogen), followed by DAPI staining. Images were observed using an Olympus FV3000 confocal microscope.
For immunofluorescence of the paraffin-embedded sections, organoids were separated using cell recovery solution (Corning) to remove Matrigel, fixed in 4% formaldehyde overnight at 4° C., and then embedded in paraffin blocks. The sections were cut and hydrated, and boiled in sodium citrate buffer (pH 6.0) for antigen recovery. The samples were permeabilized, blocked with 5% normal serum (Jackson ImmunoResearch), incubated overnight at 4° C. with each primary antibody, and labeled with a fluorescein-conjugated secondary antibody for 1 hour. Nuclei were stained with 4′-6-diamidino-2-phenylindole (DAPI; Sigma-Aldrich) and mounted with ProLong™ Glass Antifade Mountant (Thermo). Images were taken with a Zeiss LSM 800 and an Olympus FV3000 confocal microscope.
As a result, as shown in
Transcriptome analysis of the hepatic endoderm organoids cultured under the four conditions of D(+)-HEO, D(−)-HEO, S(+)-HEO, and S(−)-HEO was performed as follows.
Specifically, an mRNA library was constructed using a TruSeq Stranded mRNA LT Sample Prep Kit and then sequenced using an Illumina NovaSeq 6000 platform. The reads were aligned using HISAT2 (v2.1.0) (Kim et al., 2019) and assembled using StringTie (v1.3.4). The read counts were normalized to the trimmed average of M-values (TMM) using the edgeR (v3.26.8) R package. Highly variable genes and major components were calculated using the var and prcomp functions in the stats (v3.6.1) R package, respectively. Gene ontology and KEGG pathway analyses were performed using DAVID (Huang da et al., 2009a, b). Gene set enrichment analysis (GSEA) was performed using GSEA software (v4.0.3) with feature gene sets of MSigDB (v7.0) (Mootha et al., 2003).
As a result, as shown in
The above results suggest that the hepatic endoderm cells differentiated from human induced pluripotent stem cells can produce hepatic endoderm organoids by culture in a medium without RNE, and that the hepatic endoderm organoids can be maintained as hepatic endoderm cells at the expansion stage without R-Spondin 1 and EGF.
Hepatic endoderm organoids cultured under the four conditions of D(+)-HEO, D(−)-HEO, S(+)-HEO, and S(−)-HEO were differentiated into liver organoids using the same methods and conditions as in Example <2-2> in a culture medium with or without EGF having the composition of Table 8 or 9 (
Specifically, changes in the expression of major liver genes, including ALB, AAT, HNF4A, TDO2, G6P, CYP2C9, CYP2C19, CYP3A4, and nuclear receptors such as FXR, and CYP450 genes, were confirmed by the same methods and conditions as the RT-qPCR described in Experimental Example 1.
As a result, as shown in
The liver organoids differentiated under the four conditions were subjected to bright-field imaging, H&E staining, and immunostaining using the same methods and conditions as those described in Example <2-3> to confirm the structure of the liver organoids. RT-qPCR was performed to confirm the expression of liver marker genes at the transcriptional level using the same methods and conditions as described in Experimental Example 1, and flow cytometry was performed to confirm the number of cells expressing ALB (albumin).
As a result, as shown in
In addition, as shown in
Therefore, these results suggest that the absence of R-Spondin 1 and EGF at the expansion stage affected liver maturation in the process of differentiation into hepatic endoderm organoids, and that the removal of EGF from the culture medium during differentiation into liver organoids increased the maturation process of liver organoids by increasing the expression levels of liver and drug metabolism-related genes.
In the liver, an ATP-binding cassette transporter (ABC transporter) plays an important role in the efflux of endogenous and exogenous substances by phase II conjugation with CYP450 enzyme. Accordingly, the structure of the liver organoids differentiated from the hepatic endoderm organoids was observed with a transmission electron microscope, and the expression of genes related to apical and basolateral drug transporters in the droplet-shaped liver organoids (D-HO) and suspension-type liver organoids (S-HO) prepared in Example 2, primary human hepatocytes (PHH), HepG2 (liver cancer cell line), and 2D hPSC-derived hepatocyte-like cells (2D HLC) prepared in Comparative Example 1 was confirmed using the same methods and conditions as described in Example 1.
Specifically, the transmission electron microscopy observation procedure is as follows. The liver organoids were fixed in 2% glutaraldehyde-paraformaldehyde in 0.1 M phosphate buffer (PB), pH 7.4 for 12 hours and washed in 0.1 M phosphate buffer. After fixation for 2 hours with 1% OsO4 dissolved in 0.1 M PB, the liver organoids were dehydrated with concentration gradient ethanol (50-100%) and infiltrated with propylene oxide. The specimens were embedded in the Poly/Bed 812 kit (Polysciences). It was embedded in pure fresh resin and polymerized for 24 hours in a 65° C. electron microscope oven (TD-700, DOSAKA, Japan). Sections about 200-250 nm thick were initially cut and stained with toluidine blue (Sigma-Aldrich) for light microscopy. 70 nm thin sections were double stained with 6% uranyl acetate (EMS, 22400, 20 minutes) and lead citrate (Fisher, 10 minutes) for counterstaining. The sections cut by LEICA EM UC-7 (Leica Microsystems, Austria) using a diamond knife (Diatome) were transferred onto copper and nickel grids, and all thin parts were observed under a transmission electron microscope (JEM-1011, JEOL, Japan) at an accelerating voltage of 80 kV.
As a result, as shown in
These results suggest that the apical side membrane with microvilli develops intensively in the liver organoids located in the luminal side membrane.
The expression of the apical drug transporters MRP2, BSEP, and MDR1 in the liver organoids and the expression changes upon administration of inhibitors of each gene were confirmed by fluorescence staining.
Specifically, the liver organoids were recovered on Matrigel and washed three times with DPBS. For CDFDA (5(6)-carboxy-2′,7′-dichlorofluorescein diacetate) staining, the liver organoids treated with or without 2 mM probenecid for 3 hours were stained with 10 μM CDFDA (Sigma-Aldrich) for 15 minutes at 37° C., 5% CO2. For CLF (Choyl-Lysyl-Fluorescein) and rhodamine 123 staining, the liver organoids treated with 4 μM CLF (Corning) or 10 μM rhodamine 123 (Invitrogen) for 15 minutes each for 24 hours with or without 10 μM ketoconazole were cultured for 1 hour. All samples were washed three times with DPBS, stained with Hoechst 33342, and observed under an Olympus FV3000 confocal microscope.
As a result, as shown in
These results suggest that the prepared liver organoids have a drug release function due to the high expression of the apical efflux drug transporter by the development of the apical membrane present in the lumen rather than the basolateral side of the liver organoids.
To investigate the cellular composition of liver organoids, single-cell transcriptome analysis of S(−)-HO was performed by single-cell RNA sequencing.
Specifically, for a scRNA-seq library, Chromium Single Cell 3′Reagent Kit v3, Chromium Chip B Single Cell Kit and Chromium i7 Multiplex Kit (10X Genomics) were used. Liver organoids were isolated using an embryoid body dissociation kit (Miltenyi Biotec), filtered through a 35 μm strainer, and loaded onto a Chromium microfluidic platform to capture 7,000 individual cells. The library was sequenced with paired-end on the Illumina HiSeq X Ten platform. Sequencing the Single Cell 3′ library generated a FASTQ file containing paired-end Read 1 (with 16 bp 10x™ barcode and 12 bp UMI) and Read 2, a sample index of i7 index reads. The file was processed with Cell Ranger™ (v3.1.0) using default arguments. Reads were aligned to the human reference genome (GRCh38). Cells with less than 2,000 genes detected using Seurat (v3.0.4) R package and with UMI more than 10% were further filtered using Seurat (v3.0.4) R package and finally a 20,125×1,859 gene-specific matrix was obtained. The expression matrix was imported and analyzed using scanpy (v1.4.5.1) Python package. The cells were visualized in a two-dimensional ForceAtlas2 plot using the tl.draw_graph function and then recalculated with PAGA-initialization. Clustering was performed using the tl.leiden function with “n_neighbors=4”, “n_pcs=20” and “resolution=1”. Using the Wilcoxon rank-sum test option and the tl.rank_genes_groups function, the marker genes of clusters and cell groups were found. Gene set expression scores including hepatocyte-like, biliary-like, gallbladder-like and cell cycle were calculated using the tl.score_genes function. Gene ontology and KEGG pathway analyses were performed using DAVID.
As a result, as shown in
In addition, as shown in
In addition, as shown in
These results suggest that the liver organoid is composed of hepatocyte-like cells, biliary-like cells, and gallbladder-like cells including progenitor-like cells expressing cell-specific markers, and can mimic the liver.
Since metabolic elimination of drugs is one of the main functions of liver tissue, reproducible high functional drug metabolic capability is required in drug efficacy and toxicity tests in liver organoid models. Therefore, in order to confirm whether the liver organoids exhibit appropriate drug metabolic capability, the expression levels of major CYP450s including CYP1A2, CYP2C9, CYP2C19, CYP2D6, and CYP3A4 were measured by performing RT-qPCR using the same methods and conditions as described in Experimental Example 1 and compared with other in vitro models (liver cancer cell line (HepG2), primary human hepatocytes (PHH), and 2D hPSC-derived hepatocyte-like cells (2D HLC)). The activity of major CYP450 was measured by LC-MS/MS analysis.
Specifically, to measure the basal CYP450 activity, substrate reactions were performed in droplet-shaped liver organoids (D(−)HO), suspension-type liver organoids (S(−)HO), primary human hepatocytes (PHH), liver cancer cell line (HepG2), and 2D hPSC-derived hepatocyte-like cells (2D HLC) at 37° C., 5% CO2 for 24 hours. CYP450 isoform specific substrate cocktail sets are as follows: set A, 50 μM phenacetin for CYP1A2, 5 μM coumarin for CYP2A6, 5 μM amodiaquine for CYP2C8, 100 μM S-mephenytoin for CYP2C19, 20 μM dextromethorphan for CYP2D6, and 5 μM midazolam for CYP3A4; set B, 50 μM bupropion for CYP2B6, 90 μM diclofenac for CYP2C9, and 90 μM chlorzoxazone for CYP2E1. Each CYP450 isoform-specific substrate cocktail set was cultured in a 24-well culture plate with a final volume of 0.6 m per well. 80 μ
of the medium was collected at 2, 4, 6, and 24 hours, respectively, and the reaction was quenched by adding 80 μ
of ice-cold acetonitrile (ACN) containing 100 nM carbamazepine (CBZ) and 300 nM 4-methylumbelliferone (4-MUF). The samples were centrifuged at 16,000 g for 10 minutes at 4° C. and the supernatant was applied to liquid chromatography-tandem mass spectrometry (LC-MS/MS). Data were normalized to protein concentration.
As a result, as shown in
The above results indicate that the expression and activity of drug metabolism enzymes, CYP450, increases when liver organoids are differentiated in a medium that does not contain R-Spondin 1 and EGF at the expansion stage.
Heme (iron(III) protoporphyrin-IX) is an important cofactor for oxygen activation when bound to CYP450. Ferric citrate (FC) increases hepatic iron accumulation in macrophages and hepatocytes (Chang et al., 2018; Lim et al., 2019). Therefore, the present inventors examined whether iron(III) supplementation during the differentiation stage of liver organoids could enhance CYP450 activity (
Specifically, hepatic endoderm organoids were differentiated into liver organoids using a liver organoid differentiation medium containing 20 or 50 μM ferric citrate (FC) for 15 days by the same methods and conditions as in Example 2. For live and dead cell analysis, the liver organoids treated with or without FC were stained with a live/dead viability/cytotoxicity kit (Thermo). Images were observed using an Olympus FV3000 confocal microscope. The viability of liver organoids was measured using CCK-8 (Dojindo) assay. The values were normalized to those obtained from CellTiter-Glo® 3D cell viability assay (Promega). The survival rate (%) of the control liver organoids was normalized to 100%.
Samples were analyzed using a Prominence UFLC system with a parallel LC-20ADXR pump, autosampler, and column oven (Shimadzu) for detection and quantification of metabolites of CYP450. The sample injection amount was 10 μ, and the separation was performed on an Atlantis dC18 column (2.1 mm×50 mm id, 3 μm, Waters, Milford, MA) with a SecurityGuard C18 guard column (2.0 mm×4.0 mm id; Phenomenex, Torrence, CA) maintained at 30° C.. The flow rate of HPLC was set to 0.4 m
/min. The HPLC mobile phase consisted of A [deionized water containing 0.1% (v/v) formic acid] and B [acetonitrile containing 0.1% (v/v) formic acid]. LC-MS/MS data were collected using an Applied Biosystems SCIEX 3200 QTRAP hybrid triple quadrupole-linear ion trap mass spectrometer equipped with a TurboIonSpray interface operating in positive or negative (for CYP2E1) ESI mode. In addition, 4-hydroxy diclofenac was set to m/z 312→230 in positive mode. Data collection and analysis were performed with Analyst™ software (ver. 1.6.2; Applied Biosystems, Foster city, CA).
As a result, as shown in
In addition, as shown in
These results suggest that iron is required to increase CYP450 activity in liver organoids.
To confirm the utility of liver organoids as a cell model for drug toxicity evaluation, drug toxicity evaluation was performed in liver organoids, liver cancer cell line (HepG2), and 2D hPSC-derived hepatocyte-like cells (2D HLC).
Specifically, D-HO, S-HO, HepG2, and 2D HLC prepared by culturing in a culture medium containing iron citrate were cultured in a 96-well plate. Compounds (ticlopidine and flutamide) at 1-, 5-, 10-, 20-, and 40-fold Cmax concentrations were prepared in each base medium, and the final DMSO concentration was 0.1%. The liver organoids or cells were treated with the compounds for 24 hours, and the viability was measured using CellTiter-Glo® 3D Cell Viability Assay (Promega). The values obtained were normalized to the control group. The normalized values were used to visualize the dose-response relationship as a non-linear regression curve and to calculate IC50 values (GraphPad Prism, GraphPad Software, San Diego, CA). In addition, the sensitivity of different cell types to each compound tested was shown as a heatmap of IC50 values (GraphPad Prism).
As a result, as shown in
To confirm the utility of liver organoid as a cell model for drug metabolic capability evaluation, CYP450-mediated drug metabolic capability was compared in liver organoids (D-HO FC and S-HO FC) and primary human hepatocytes (PHH).
Specifically, compounds including amitriptyline for CYP2D6 and CYP2C19, chlorpromazine for CYP2D6, and diclofenac for CYP2C9 and UGT2B7 were used to measure the amount of prodrugs in the media of liver organoids and PHH. The compounds were treated at a concentration of 1 μM for 24 hours at 37° C. in 5% CO2. They were cultured in each 24-well culture plate to a final volume of 0.7 m per well. 60 μ
of medium was collected at 1.5, 3, 6, 12, and 24 hours, respectively, and the reaction was quenched by adding 60 μ
of ice-cold ACN containing 100 nM CBZ and 300 nM 4-MUF. The samples were centrifuged at 16,000 g for 10 minutes at 4° C. and the supernatant was applied to liquid chromatography-tandem mass spectrometry (LC-MS/MS). The values of compound only (organic or cell free) were used as a control. Data were normalized to protein concentration.
As a result, as shown in
Acetaminophen (APAP), a safe and effective analgesic and antipyretic, is known to undergo extensive hepatic metabolism through two pathways: detoxification (conjugation such as glucuronidation and sulfation) and bioactivation (CYP450-mediated oxidation) (Hodgman and Garrard, 2012). Acetaminophen metabolism was tested under non-cytotoxic concentrations in D-HO, S-HO, PHH, HepG2 and 2D HLC. Conjugate reactions by UGT (UDP-glucuronosyl transferase) and SULT (sulfotransferase) are the major metabolic pathways for APAP metabolism (
Specifically, to measure the metabolites of APAP, reactions were performed in PHH, D-HO, S-HO, HepG2, and 2D HLC treated with 10 mM APAP for 24 hours at 37° C. in 5% CO2. APAP was treated to a final volume of 0.7 m per well in each 24-well culture plate. 70 μ
of medium was collected at 3, 6, 12 and 24 hours, respectively, and the reaction was quenched by adding 70 μ
of ice-cold ACN containing 100 nM BR-A-563 as an internal standard. The samples were centrifuged at 16,000 g for 10 minutes at 4° C. and the supernatant was applied to liquid chromatography-tandem mass spectrometry (LC-MS/MS). Data were normalized to protein concentration.
As a result, as shown in
Fimasartan (FMS), an angiotensin II receptor blocker, is used to treat hypertension and is known to be metabolized by CYP2C9, CYP3A4, and CYP3A5. FMS metabolism was tested using D-HO, S-HO, PHH, HepG2, and 2D HLC at the concentrations that did not show cytotoxicity. FMS is further metabolized to BR-A-557 by CYP3A4/5 and to BR-A-535 by CYP3A4, and CYP2C9, CYP3A4, and CYP3A5 are involved in the formation of FMS S-oxide (
Specifically, to measure the metabolites of fimasartan (FMS), reactions were performed in PHH, D-HO, S-HO, HepG2, and 2D HLC treated with 50 μM FMS for 24 hours at 37° C. in 5% CO2. FMS was processed to a final volume of 0.7 m per well in each 24 well culture plate. 70 μ
of medium was collected at 3, 6, 12 and 24 hours, respectively, and the reaction was quenched by adding 70 μ
of ice-cold ACN containing 100 nM BR-A-563 as an internal standard. The samples were centrifuged at 16,000 g for 10 minutes at 4° C. and the supernatant was applied to liquid chromatography-tandem mass spectrometry (LC-MS/MS). Data were normalized to protein concentration.
As a result, as shown in
These results suggest that liver organoids can serve as an in vitro model to study and test CYP450-mediated drug metabolism.
Whether liver organoids can be used to evaluate cardiotoxicity induced by drug metabolites was confirmed by treating liver organoids with cyclophosphamide and terfenadine.
Cyclophosphamide (CP) is an alkylating agent used as an anticancer chemotherapy drug and is known to cause cardiotoxicity. CP is activated by hepatic CYP450, a group of drug metabolism enzymes including CYP2B6, CYP2C9/C19, and CYP3A4/A5, to form 4-hydroxy-CP and coexist with AldoCP, a tautomer. In the heart, AldoCP is broken down into acrolein and phosphoramide mustard (PM) (
Specifically, the electrical activity of Cardiosight®-S (NEXEL Co., South Korea), the hiPSC-CM, was measured using an MEA system (Axion BioSystems, Maestro, US) at 37° C. and perfused with 5% CO2, 20% O2, and 75% N2. The hiPSC-CMs were first seeded in a 12-well MEA plate at the density of 4×104 cells per well and maintained for 7 days in a cardiomyocyte culture medium provided by NEXEL Co. to stabilize with half-mid changes performed every 2 days. One week later, the culture medium was replaced with a liver organoid differentiation medium (DM). Transwell inserts (Corning) were then placed in each well, and FC-treated S(−)-HO was seeded in the inserts, followed by culture for 3 days. On the day of compound application, the culture medium was completely removed from the wells and inserts and fresh medium was added to ensure the correct volume per well (2 m/well total). Cells were allowed to equilibrate for 4 hours, and online parameters were monitored to ensure a stable baseline for at least 40 minutes. The cells were exposed to cyclophosphamide at a single dose per well. After application of the drug or control (0.1% DMSO), field potentials were measured every 5 minutes for 30 seconds for 72 hours. The field potential signals were recorded and analyzed using Axion BioSystems' integrated studio (AxIS) software to measure the beating frequency and field potential duration. Fredericia's velocity correction algorithm (FPDcF) is commonly used to correct for velocity-dependent effects. Herein, FPDcF=FPD/Beat Period 0.33. Data were normalized to pretreated control values.
As a result, as shown in
In addition, as shown in
Terfenadine (TER) can cause life-threatening ventricular arrhythmias. Terfenadine is metabolized by CYP3A4 in the liver, and the main active metabolite is fexofenadine (FEX), which is known to have less toxic effects than terfenadine (
The cardiotoxicity of terfenadine was measured in liver organoids by the same methods and conditions as in Experimental Example <9-1>, except that terfenadine was treated instead of cyclophosphomide.
As a result, as shown in
In conclusion, the above results suggest that the liver organoids of the present invention can serve as an in vitro model for studying and testing the target organ toxicity induced by hepatic CYP450-mediated drug metabolism.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10-2021-0024905 | Feb 2021 | KR | national |
| 10-2021-0024919 | Feb 2021 | KR | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/KR2021/005001 | 4/21/2021 | WO |
