Efficient Generation of Small Intestinal Epithelial-like Cells from Human iPSCs for Drug Absorption and Metabolism Studies

Abstract

The small intestine plays an important role in the absorption and metabolism of oral drugs. In the current evaluation system, it is difficult to predict the precise absorption and metabolism of oral drugs. In this study, we generated small intestinal epithelial-like cells from human induced pluripotent stem cells (hiPS-SIECs), which could be applied to drug absorption and metabolism studies. The small intestinal epithelial-like cells were efficiently generated from human induced pluripotent stem cell by treatment with WNT3A, R-spondin 3, Noggin, EGF, IGF-1, SB202190, and dexamethasone. The gene expression levels of small intestinal epithelial cell (SIEC) markers were similar between the hiPS-SIECs and human adult small intestine. Importantly, the gene expression levels of colonic epithelial cell markers in the hiPS-SIECs were much lower than those in human adult colon. The hiPS-SIECs generated by our protocol exerted various SIEC functions. In conclusion, the hiPS-SIECs can be utilized for evaluation of drug absorption and metabolism.

Keywords: drug absorption; drug metabolism; human iPSCs; intestinal epithelial-like cells.

Graphical abstract

Figure 1

LY2090314 Treatment Promoted the Intestinal Progenitor Cell Differentiation of Human iPSCs (A) The procedure for intestinal progenitor cell differentiation from human iPSCs (Tic) is shown. Definitive endoderm cells were treated with solvent (DMSO), 40 μM SB216763, 3 μM CHIR99021, 20 nM LY2090314, 5 μM BIO, or 5 μM BIO +10 μM DAPT for 4 days. (B) The gene expression levels of CDX2, PDX1, and AFP were examined by real-time RT-PCR analysis. On the y axis, the gene expression levels in the definitive endoderm cells (DECs) were taken as 1.0. (C) The CDX2 protein expression levels were measured by western blotting analysis. (D) Immunostaining analysis of CDX2 (green) was performed in the human iPSC-derived intestinal progenitor cells. Nuclei were stained with DAPI (blue). Scale bars represent 50 μm. All data are presented as means ± SEM of three independent experiments. Significant differences between the definitive endoderm cells and drug-treated groups were evaluated by one-way ANOVA followed by Dunnett's post hoc test (^∗p < 0.05, ^∗∗p < 0.01, ^∗∗∗p < 0.001: compared with “DECs”). See also Figure S1.

Figure 2

WNT3A, R-Spondin 3, Noggin, EGF, IGF-1, SB202190, and DEX Treatments Promoted Intestinal Epithelial Cell Differentiation (A) The procedure for small intestinal epithelial-like cell differentiation from human iPSCs (Tic) is shown. Intestinal progenitor cells were treated with solvent (DMSO), 10 nM LY2090314, 10 μM SB202190, 10 mM nicotinamide, 1 μM DEX, 1 μM triiodothyronine (T3), 10 μM SB431542, 20 ng/mL HGF, 50 ng/mL EGF, 20 ng/mL IGF-1, 25% WNT3A CM (conditioned medium of WNT3A-expressing cells), 25% WRN CM (conditioned medium of WNT3A, R-spondin 3, Noggin-expressing cells), 10 nM [Leu15]-gastrin 1, and 100 nM trichostatin A for 12 days, or with 5 μM BIO +10 μM DAPT for 16 days. (B and C) The gene expression levels of villin 1 and ISX were examined by real-time RT-PCR analysis. On the y axis, the gene expression levels in the DMSO-treated cells were taken as 1.0. All data are presented as means ± SEM of triplicate experiments. Significant differences between the vehicle and drug-treated groups were evaluated by one-way ANOVA followed by Dunnett's post hoc test (^∗p < 0.05, ^∗∗p < 0.01, ^∗∗∗p < 0.001: compared with “DMSO”).

Figure 3

Efficient Small Intestinal Epithelial-like Cells Were Differentiated from Human iPSCs (A) The procedure for small intestinal epithelial-like cell differentiation from human iPSCs (Tic) is shown. Details are described in Experimental Procedures. (B) Temporal gene expression levels of villin 1, ISX, and CDX2 in the human iPSC-derived small intestinal epithelial-like cells (days 20, 24, and 28) were examined by real-time RT-PCR analysis. On the y axis, the gene expression levels in the human iPSC-derived small intestinal epithelial-like cells (day 20) were taken as 1.0. Statistical significance was evaluated by one-way ANOVA followed by Tukey's post hoc test (p < 0.05). Groups that do not share the same letter are significantly different from each other. (C) The gene expression levels of villin 1, ISX, CDX2, ANPEP and SI in human iPSC-derived small intestinal epithelial-like cells at day 28 (hiPS-SIECs) and the human adult small intestine (Small Intestine) were examined by real-time RT-PCR. On the y axis, the gene expression levels in the small intestine were taken as 1.0. Statistical analyses were performed using the unpaired two-tailed Student's t test (^∗p < 0.05, ^∗∗p < 0.01). N.S., not significant. (D) The percentages of villin 1-positive and SI-positive cells were measured by FACS analysis. (E) Immunostaining analysis of villin 1 (red) was performed in the hiPS-SIECs. Nuclei were stained with DAPI (blue). Scale bar represents 10 μm. (F) Alkaline phosphatase (ALP) activities of hiPS-SIECs and mouse embryonic fibroblasts (MEF) were confirmed by ALP staining. Scale bars represent 100 μm. (G) Transmission electron micrographs of monolayer of the hiPS-SIECs. Scale bar represents 2 μm. All data are presented as means ± SEM of three independent experiments. See also Figure S2.

Figure 4

Expression Analysis of Small Intestinal Epithelial Cell Markers and Colonic Epithelial Cell Markers (A and B) The gene expression levels of small intestinal epithelial cell markers (A) and colonic epithelial cell makers (B) in the human iPSC (Tic)-derived small intestinal epithelial-like cells (hiPS-SIECs), human adult small intestine (Small Intestine), and human adult colon (Colon) were examined by real-time RT-PCR analysis. On the y axis in (A), the gene expression levels in the human adult small intestine were taken as 1.0. On the y axis in (B), the gene expression levels in the human adult colon were taken as 1.0. Statistical significance was evaluated by one-way ANOVA followed by Tukey's post hoc test (p < 0.05). Groups that do not share the same letter are significantly different from each other. (C) Global intestinal gene expression analyses were performed in undifferentiated human iPSCs, hiPS-SIECs, small intestine, and colon. Heatmap represents the average log₂-fold difference. Data are presented as the means ± SEM of three independent experiments.

Figure 5

Expression Analysis of Drug-Metabolizing Enzymes and Drug Transporters (A) The gene expression levels of drug-metabolizing enzymes in the human iPSC (Tic)-derived small intestinal epithelial-like cells (hiPS-SIECs), human adult small intestine (Small Intestine), and human adult colon (Colon) were measured by real-time RT-PCR analysis. (B and C) The gene expression levels of apical transporters (B) and basolateral transporters (C) in the hiPS-SIECs, small intestine, and colon were examined by real-time RT-PCR analysis. On the y axis, the gene expression levels in the small intestine were taken as 1.0. All data are presented as means ± SEM of three independent experiments. Statistical significance was evaluated by one-way ANOVA followed by Tukey's post hoc test (p < 0.05). Groups that do not share the same letter are significantly different from each other. See also Figure S3.

Figure 6

The Drug Absorption and Metabolism Capacities of hiPS-SIECs (A) The human iPSC (Tic)-derived small intestinal epithelial-like cells (hiPS-SIECs) were treated with solvent (DMSO), 20 μM rifampicin (RIF), or 100 nM 1α,25-dihydroxyvitamin D3 (VD3) for 48 hr. The gene expression levels of CYP3A4 were examined by real-time RT-PCR analysis. On the y axis, the gene expression levels in the DMSO-treated cells were taken as 1.0. (B) The CES2 activity levels in the hiPS-SIECs were measured by treatment with fluorescein diacetate (a CES2 substrate) in the presence or absence of 1 mM loperamide (a CES2 inhibitor). (C) Monolayer formation of hiPS-SIECs in the presence or absence of 10 mM capric acid (C10; an absorption-enhancing agent). TEER value of hiPS-SIECs monolayer was measured by Millicell-ERS2. (D) The permeability of lucifer yellow (LY) across hiPS-SIECs monolayer. (E) The apical-to-basolateral permeability of rhodamine123 across the hiPS-SIECs monolayer in the presence or absence of 10 μM cyclosporine A (CysA; an MDR1 inhibitor). (F) The hiPS-SIECs were treated with 25 μM D-Ala-Leu-Lys-AMCA (blue) for 4 hr in the presence or absence of 100 μM captopril (a PEPT1 inhibitor). After the uptake of D-Ala-Leu-Lys-AMCA, the cells were fixed. Immunostaining analysis of E-cadherin (red) was performed in the hiPS-SIECs. Scale bars represent 50 μm. All data are presented as means ± SEM of three independent experiments. Statistical analyses were performed using the unpaired two-tailed Student's t test (^∗p < 0.05, ^∗∗p < 0.01). See also Figures S3 and S4.