Primary hepatocytes in RAFT™ 3D Cell Culture System –a model for hepatocyte toxicity studies
Therese Willstaedt1, Lubna Hussain1, Maureen Bunger2, Theresa D’Souza1
1
Lonza Walkersville, Inc., Walkersville, MD, USA;
2
Lonza Research Triangle Park, NC, USA

Primary hepatocytes
in RAFT 3D Cell Culture
System – a model forhepatocyte toxicity
studies™

Primary hepatocytes in RAFT™ 3D Cell Culture System –a model for hepatocyte toxicity studies

2

Introduction
Hepatocytes are the primary cell type of the liver and function
to provide the majority of the detoxification in the body. In thepharmaceutical industry, there is an increasing demand for hepatocytebased models that mimic human in vivo toxicity.1, 2 Typical in vitro
drug toxicity screening has incorporated hepatocytes grown in a
two-dimensional (2D) format, cultured between collagen-coated tissue
culture plastic and Matrigel® (“Sandwich Culture”). However, literature
has reported that although primary hepatocytes briefly maintainsome functional capabilities in 2D culture, such as the production of
drug metabolizing enzymes, they rapidly lose their morphology alongwith the majority of liver-specific functions.3-5 A model demonstratingstronger responses and showing more stable maintenance of liverfunctions is desirable when assays that need more than 4 or 5 days inculture are required. The potential of three-dimensional (3D) models to
mimic the in vivo cellular environment more closely have made themattractive alternatives to 2D culture systems.

Empty well

We offer a novel RAFT™ (Real Architecture for Tissue) 3D Cell Culture
System which allows the creation of tissue-like structures. The 3D
matrix of the type 1 collagen-based RAFT™ 3D Cell Culture Systemprovides a more natural cell culture environment, supporting primarycell phenotypes for longer durations than standard 2D culture systems.
This feature of the RAFT™ 3D Cell Culture System potentially enables
better predictive value for toxicity and metabolism studies when longterm studies are beneficial.
In this White Paper, we report a 3D hepatocyte model constructed using
the RAFT™ 3D Cell Culture System (Figure 1) and characterization. The
model consists of primary hepatocytes embedded in compressed
RAFT™ Hydrogel. We compare cell viability, cell morphology andmaintenance of Cytochrome P450 (CYP) activity of primary humanhepatocytes grown in the traditional Sandwich Culture with that of cells
cultured in RAFT™ 3D Cell Culture. Our results show that the RAFT™ 3D
Cell Culture System improves the long-term maintenance of hepatocyte
metabolic functions.

Mix neutralized
collagen and cells
Pipet into well

Incubate at 37°C for 15 minutes toform hydrogel

Place absorber on top ofhydrogelLiquid starts to be absorbed

15 minutes

Figure 1
Process overview for RAFT™ 3D Cell Culture System.

Culture formation completePrimary hepatocytes in RAFT™ 3D Cell Culture System –a model for hepatocyte toxicity studies

3

Materials and methods

Cell culture• Cryopreserved human primary hepatocytes (Lonza,
cat. no. HUCP1 or HUCPG)• Collagen coated 96-well plates (Corning, cat. no. 354407)• 96-well tissue culture treated plates (Greiner, cat. no. 655180)• RAFT™ Reagent Kit for 3D Culture (Lonza, cat. no. 016-0R94)• RAFT™ Absorbers (Lonza, cat. no. 016-0R92)• Matrigel® Matrix (Corning, cat. no. 354234)• CellTiter-Glo® 3D Viability Assay – CTG (Promega, cat. no. G9681)• alamarBlue® Cell Viability Reagent (Thermo Fisher Scientific,
cat. no. DAL1025)• P450-Glo™ CYP1A2 Assay (Promega, cat. no. V8421)• P450-Glo™ CYP2B6 Assay (Promega, cat. no. V8321)• P450-Glo™ CYP3A4 Assay (Promega, cat. no. V9001)• Methanol (Sigma, cat. no. 179337)• Normal Goat Serum – NGS (Sigma, cat. no. G6767)• Anti-ZO-1 antibody (Thermo Fisher Scientific, cat. no. 33-9100)• DAPI (Thermo Fisher Scientific, cat. no. D1306)• Alexa Fluor 555 (Thermo Fisher Scientific, cat. no. A21425)• Mouse IgG1 (Dako, cat. no. X0931)• Phosphate Buffered Saline – PBS (Lonza, cat. no. 17-516Q)• Glycerol (Thermo Fisher Scientific, cat. no. BP229-1)• Rifampicin (Sigma, cat no. R3501)• Phenacetin (Sigma, cat. no. 77440)• Bupropion (Sigma, cat. no. B102)• Testosterone (Sigma, cat. no. T1500)• Salicylamide (MP Biomedicals, cat. no. 102835)• Human Cryopreserved Hepatocyte Thawing Medium (Lonza,
cat. no. MCHT50)• HBM™ Hepatocyte Basal Medium (Lonza, cat. no. CC-3199)• HCM™ SingleQuots™ Kit – Hepatocyte Culture Medium (Lonza,
cat. no. CC-4182)• Plating Medium (Lonza, cat. no. MP100-1)• Plating Medium Supplement (Lonza, cat. no. MP100-2)• Albumin Elisa Kit (Thermo Fisher Scientific, cat. no. EHALB)• Urea Assay Kit (Abnova, cat. no. KA1652)

Preparation of HCM™ Hepatocyte Culture Medium
Hepatocyte Culture Medium SingleQuots™ were thawed overnight at 4°C.
In a Biosafety Cabinet (BSC) thawed SingleQuots™ were added one at atime using a separate pipet for each growth factor, to a 500 mL bottle of
HBM™ Medium, and swirled to mix thoroughly.
Human hepatocytes
Cryopreserved hepatocytes were thawed at 37°C. Each ampoule wasdiluted in 50 mL Human Hepatocyte Thawing Medium and centrifuged
at 100 x g for 8 minutes at room temperature. After carefully aspirating
most of the supernatant and leaving approximately 100 µL of
Human Hepatocyte Thawing Medium over the pellet, the pellet was
resuspended by tapping the tube against the palm of the hand. For
counting, a small aliquot of concentrated cell suspension was dilutedand counted using the trypan blue exclusion method. Because many
hepatocytes contain two or more nuclei6, it is strongly recommended
that these cells be counted via trypan blue exclusion methods
rather than procedures utilizing nuclear staining methodology. Aftercounting cells, suspension was diluted with complete HCM™ Medium.
A cell seeding density of 45,000–65,000 cells per 96-well is optimal.
For a seeding density of 47,000 cells per well, for example, the cellconcentration was adjusted to 9.4 x 105/mL (Sandwich Culture) or
1.9 x 107/mL (RAFT™ 3D Cell Culture).
Sandwich Culture
To the wells of collagen coated 96-well plates, 50 µL complete HCM™
Medium was added followed by 50 µL of cell suspension, for example, atcell concentration of 9.4 x 105/mL to give a final cell density 47,000 cells
per well. Cells were allowed to settle by leaving the plates undisturbed
in the BSC for 5 minutes. Plates were then placed in a 37°C, 5% CO2
incubator for 2 hours. To remove non-viable cells, the medium wascarefully aspirated and replaced with fresh HCM™ Medium. Cultures
were incubated for an additional 2 hours. The medium was aspirated
and the plates were overlaid with 0.3 mg/mL Matrigel® in HCM™ Medium.
Cultures were refed daily with 100 µL HCM™ Medium per well.
RAFT™ 3D Cell Culture
Manufacturer’s instructions for construction of RAFT™ 3D Cell Culture
was followed except one quarter of the recommended volume (60 µL
cell seeded collagen hydrogel per well of a 96-well plate, rather than
the standard 240 µL) of hydrogel was used (see Lonza Tech Note:
Construction of a 3D hepatocyte model using the RAFT™ 3D Cell Culture
System). Final cell density in RAFT™ 3D Cell Cultures was 45,000–
65,000 cells per well. Cultures were refed daily with 100 µL warm
HCM™ Medium per well.

Assay kits
Assay kits (alamarBlue® Cell Viability Reagent, P450-Glo® CYP1A2,
CYP2B6 and CYP3A4) were used as per the manufacturers’ instructions.
Cells were incubated with the reagent for 80 minutes at 37°C prior toassay evaluation.
Immunofluorescence
Sandwich Culture and RAFT™ 3D Cell Culture were fixed with ice cold
Methanol for 10 minutes and rinsed twice with PBS. Cultures were
blocked with 10% NGS in PBS for 40 minutes at room temperature. The
blocked cultures were incubated with 50 µL per well of 5 µg/mL ZO-1
antibody or mouse IgG1 at 4°C overnight and then rinsed three times
with PBS. Cultures were incubated with 50 µL per well of a 1:200 dilution(10 µg/mL) of Alexa Fluor 555 in 1% NGS at 37°C for 30 minutes.
After rinsing three times with PBS, cultures were incubated with 50µL per well of 100 µM DAPI in PBS at room temperature for 8 minutes.
Cultures were rinsed three times with PBS and 50% Glycerol in PBS wasplaced in each well.
CYP450 activity quantitation
Inducers and substrates stock solutions at 1000x were prepared in
DMSO and stored at -20°C. For CYP3A4, on the day of induction, theculture medium was aspirated and 100 µL HCM™ Medium containing
either 10 µM rifampicin or 1:1000 DMSO (Control) was applied for
72 hours with daily refeeds. Cultures were incubated in a 37°C, 5% CO2
incubator.
After the cells were exposed to inducer (or DMSO control) for 72 hours,
they were rinsed once with warm HCM™ Medium. The corresponding
substrates phenacetin (100 µM, CYP1A2), bupropion (250 µM, CYP
2B6) or testosterone (200 µM, CYP3A4) were applied to induced
and non-induced (DMSO control) wells for 15 minutes (phenacetinor testosterone) or 20 minutes (bupropion) in 100 µL per well HCM™
Medium. The cultures were placed in the incubator on an orbital
shaker at 95 rpm. At the end of the incubation period, the culture
supernatants were collected. Basal CYP activities of non-induced cells
were determined by evaluating supernatants of DMSO control wells.
Metabolite quantification was determined by Liquid Chromatography
Mass Spectrometry (LCMS).

Primary hepatocytes in RAFT™ 3D Cell Culture System –a model for hepatocyte toxicity studies

Results and discussion
Cell viability of hepatocytes in RAFT™ 3D Cell Culture and Sandwich
Culture can be determined using the alamarBlue® Reagent
The alamarBlue® Cell Viability Reagent was used to determine theviability of human hepatocytes in RAFT™ 3D Cell Culture and Sandwich
Culture (Figure 2A). The alamarBlue® Reagent uses resazurin, a cellpermeable, blue, non-fluorescent compound, as the active ingredient.
Resazurin is reduced to resorufin, a red and highly fluorescentcompound; within the cytoplasm of the cell.7 Viable cells continuously
convert resazurin to resorufin, and thereby increase the fluorescence ofthe culture medium. The data shown in Figure 2A illustrates that, using
this reagent, human hepatocytes maintained a higher viability in
RAFT™ 3D Cell Culture than in Sandwich Culture.
The morphology of hepatocytes embedded in the collagen matrixof RAFT™ 3D Cell Culture is shown in Figure 2B. The individual cells
show a rounded morphology. This may be contrasted to the cuboidal
morphology of hepatocytes grown in Sandwich Culture.8
Apmol/million/min

4

1,600
1,400
1,200
1,000
800
600
400
200
0

D4

D6

Sandwich Culture
RAFT™ 3D Cell Culture

D8Days in culture

D13

D17

Acellular Sandwich Culture
Acellular RAFT™ 3D Cell Culture

B

Day 5

Figure 2
Cryopreserved human hepatocytes exhibit higher viability in RAFT™ 3D Cell Culture thanin Sandwich Culture. (A) The viability of cryopreserved human hepatocytes cultured in
RAFT™ 3D Cell Culture and Sandwich Culture were compared using the alamar Blue® Cell
Viability Reagent. Cells were plated at 47,000 cells per well in each respective model. Error
bars represent standard deviations between triplicates of one experiment. The survival of
human hepatocytes is more robust in RAFT™ 3D Cell Culture than in traditional Sandwich
Culture. (B) The morphology of primary human hepatocytes in RAFT™ 3D Cell Culture andSandwich Culture. In RAFT™ 3D Cell Culture, the cells exhibit a rounded morphology within
the collagen matrix.

Day 17RAFT™ 3D Cell Culture

Sandwich CulturePrimary hepatocytes in RAFT™ 3D Cell Culture System –a model for hepatocyte toxicity studies

Fluoresence intensty

RAFT™ 3D Cell Cultures of human hepatocytes maintain high viability
when plated in serum containing medium or in serum-free medium
The RAFT™ 3D Cell Cultures of human hepatocytes were constructed
and maintained in HCM™ Medium, a serum-free medium. To confirm thatthe absence of serum had no adverse effects on the cultures, RAFT™ 3D
Cell Culture Hepatocytes were tested for morphology and viability at 2,
4, 6, 24 and 48 hours post plating in Plating Medium containing serum
compared to that in HCM™ Medium followed by exchange of media to
HCM™ Medium. As shown in Figure 3, for 48 hours post plating, serumcontaining Plating Medium was comparable to HCM™ Medium. Similar
results were obtained for other time points (data not shown). Sandwich
Cultures were tested for 2 and 4 hours post plating in Plating Medium
and were comparable for morphology and viability to hepatocytes
plated in HCM™ Medium (data not shown).

5

A

B

C

D

1,400
1,200
1,000

Figure 4
Cryopreserved human hepatocytes form tight junctions in RAFT™ 3D Cell Culture.
Cryopreserved human hepatocytes were plated at 47,000 cells per well in the RAFT™ 3D
Cell Culture and cultured for 4 days (RAFT™ 3D Cell Culture: A, B) or 6 days (Sandwich
Culture: C, D). Methanol fixed cultures were stained for tight junctions with the ZO-1
antibody (red) and counter stained with DAPI (blue). (A) ZO-1 stained RAFT™ 3D Cell
Culture 20x. (C) ZO-1 stained Sandwich Culture 20x. Insets (B, D) are enlarged to show
detail.

800
600
400
200

Serum

Serum-free

Figure 3
Human hepatocytes exhibit similar viabilities when plated in serum-containing medium
and in serum-free medium. Hepatocytes were plated at 65,000 cells per well in either
serum-containing medium (Plating Medium) or in serum-free medium (HCM™ Medium).
Cultures were refed daily. At 48 hours post plating, cells in Plating Medium were refed with
HCM™ Medium. At 72 hours post plating, the relative cell viability was determined using thealamarBlue® Reagent. The data shows that cell viabilities in both conditions are similar.

Tight junctions are formed in human hepatocytes in RAFT™ 3D Cell
Culture and in Sandwich Culture
Tight junctions are of physiological importance to hepatocytes, notonly do they modulate the passage of small molecules and ions
between cells9 but they also function to keep bile in the canaliculi andout of the blood circulation.10 Immunofluorescence staining of humanhepatocytes with the ZO-1 antibody shows that tight junctions areformed in both RAFT™ 3D Cell Cultures (Figures 4 A, 4 B) and Sandwich
Cultures (Figures 4C, 4D).

Albumin secretion by human hepatocytes is similar in the RAFT™
3D Cell Culture and in Sandwich Culture
The maintenance of serum albumin concentrations in the blood is an
important function of hepatocytes. Albumin secretion by these cells
maintains the osmotic pressure of the body whereby fluid is pulled
into the capillaries. Reduction in serum albumin results in edema andimpaired kidney function.11 We compared the albumin concentration in
the culture medium of hepatocytes grown in the RAFT™ 3D Cell Culture
and in Sandwich Culture using a human albumin ELISA kit (Figure 5).
The results show similar concentrations of albumin in conditioned
medium of human hepatocytes grown in RAFT™ 3D Cell Culture and in
Sandwich Culture.
[ALB] (pg/mL)

02,000,000
1,800,000
1,600,000
1,400,000
1,200,000
1,000,000
800,000
600,000

Figure 5Albumin secretion by human hepatocytes in RAFT™ 3D Cell Culture and in Sandwich
Culture are similar. Cells were plated at 45,000–65,000 cells per well in each respectivemodel. Culture media was changed daily. Supernatants of 24-hour conditioned medium
were collected on the culture days indicated. Culture medium from wells containing nocells used as a control.

400,000
200,000
0
Sandwich Culture
RAFT™ 3D Cell Culture
Media

Glucose utilization and lactate and urea production by primary humanhepatocytes is lower in RAFT™ 3D Cell Culture than in Sandwich
CultureSince primary human hepatocytes are differentiated cells and do not
proliferate, an increased cellular uptake of glucose occurs with the mostenergy-requiring metabolic processes other than cell growth. In thiscase, hepatocytes in RAFT™ 3D Cell Culture require less glucose thanthose in Sandwich Culture, indicating a healthier physiological state ofhepatocytes in RAFT™ 3D Cell Culture than in Sandwich Culture: althoughhepatocytes are more metabolically active in RAFT™ 3D Cell Culture thanin Sandwich Culture (Figure 2B), their glucose consumption is lower(Figure 6A).
Lactate is the product of anaerobic glycolysis and is correlated withglucose consumption.12 The greater the glucose consumption, thegreater the lactate production (Figure 6B).

A

Glucose concentration[Urea] (nmol)

Basal urea production measured over 26 days showed increase in both
RAFT™ 3D Cell Culture and Sandwich Culture up to day 14, but decreasedin Sandwich Culture and maintained in RAFT™ 3D Cell Culture whenmeasured on day 26 (Figure 6C).
2.5
2
1.5
1
0.5
0

D1

D3

D6

D10

D14

D26

Days in culture

Sandwich Culture
RAFT™ 3D Cell Culture
Control

Urea production
5
4
3
2
1
0

D1

D3

D6

-1

D10

D14

D26

Days in culture

Sandwich Culture
RAFT™ 3D Cell Culture
Control
Figure 6
Glucose utilization and lactate and urea production by primary human hepatocytes
is lower in RAFT™ 3D Cell Culture than in Sandwich Culture. Cells were plated at
45,000–65,000 cells per well in each respective model. Cultures were refed daily.
Supernatants of 24-hour conditioned medium were collected on the culture days
indicated. Culture medium from wells containing no cells was used as a control. (A)Glucose concentration (B) lactate concentration (C) urea production.

Basal and induced (CYP3A4) CYP activities in human hepatocytes arehigher for longer duration in RAFT™ 3D Cell Culture than in Sandwich
CultureThe presence of functional Cytochrome P450 (CYP) enzymes is anotherimportant characteristic of healthy hepatocytes. These enzymes arefound primarily in liver and intestinal cells. The CYPs belonging to the
CYP 1, 2 and 3 families account for the metabolism of 70–80% of theclinically used drugs.13 Of these enzymes, CYP3A4 metabolizes the
majority of known drugs, CYP2B6 metabolizes approximately 10% of
drugs and CYP1A2 metabolizes a growing number of newly developed
drugs.14, 15 Table 1 summarizes the inducer (CYP3A4) substrates andmetabolites for each CYP isoform.
Basal and induced (CYP3A4) CYP activities in primary humanhepatocytes were measured over 17 days. Figure 7 shows that using
both indirect (Figures 7 A, 7 C and 7 E) and direct (Figures 7 B, 7 D and
7 F) activity measurements, the basal CYP activity is higher and morestable when hepatocytes are cultured in RAFT™ 3D Cell Culture. Figure 8
shows that, in addition to facilitating higher basal CYP activities, RAFT™
3D Cell Culture allows for rifampicin induction levels of CYP 3A4 to behigher over a longer duration than in Sandwich Culture. This data issummarized in Table 2.

B Lactate concentration[Lactate] (g/L)

C[Urea] (nmol)

Primary hepatocytes in RAFT™ 3D Cell Culture System –a model for hepatocyte toxicity studies

6

0.8
0.7
0.6
0.5
0.4
0.3

CYP450 Isoform
CYP1A2

0.2
0.1
0

D1

Sandwich Culture
RAFT™ 3D Cell Culture
Control

D3

D6
D10
D14
Days in culture

D26

Inducer-

Substrate
100 µM phenacetin

Metabolite
Acetaminophen

CYP2B6-250 µM bupropion

OH-bupropion

CYP3A4

10 µM rifampicin

200 µM testosterone

6ß-hydroxytesterone

Table 1
CYP inducers, substrates and metabolites.

1A2-Glo™ Assay100

7

B LCMS 1A2
Basal activity (pM/10e6 cells/min)A
Basal activity (RLU)

Primary hepatocytes in RAFT™ 3D Cell Culture System –a model for hepatocyte toxicity studies

80
60
40
20

D4

D6

2B6-Glo™ Assay
60

D13

30
20
10
D6

3A4-Glo™ Assay

Basal activity (RLU)

Sandwich Culture
RAFT™ 3D Cell Culture

E

600

D8
Days in culture

D13

300
200
100

Sandwich Culture
RAFT™ 3D Cell Culture

D16

D6

D8
Days in culture

4
3
2
1

D4

Sandwich Culture
RAFT™ 3D Cell Culture

400

D4

D8
Days in culture

5

0

D17

500

0

D4

D LCMS 2B6

40

D4

0.5

Sandwich Culture
RAFT™ 3D Cell Culture

50

0

1

0

D17

Basal activity (pM/10e6 cells/min)C
Basal activity (RLU)

Sandwich Culture
RAFT™ 3D Cell Culture

D8Days in culture

1.5

D13

D17

F

LCMS 3A4

Basal activity (pM/10e6 cells/min)

02

6.00E+01

D8
Days in culture

D16

5.00E+01
4.00E+01
3.00E+01
2.00E+01
1.00E+01
0.00E+01

D4

D8
Days in culture

D16

Sandwich Culture
RAFT™ 3D Cell Culture

Figure 7
CYP450 Culture of human hepatocytes is higher for longer culture durations in RAFT™ 3D Cell Culture than in Sandwich Culture. Human hepatocytes were plated at
45,000–65,000 cells per well in RAFT™ 3D Cell Culture and in Sandwich Culture. Basal CYP activities were determined by analyzing supernatants from uninduced cells
using the P450-Glo™ Assays (Figures 7A, 7C and 7E). In separate experiments the basal CYP450 activities were determined by incubating uninduced cells with the appropriate substrate(Table 1) and quantitating the metabolites by LCMS (Figures 7B, 7D and 7F).

Primary hepatocytes in RAFT™ 3D Cell Culture System –a model for hepatocyte toxicity studies

A

3A4-Glo™ Assay

P450-Glo™ Assay

Fold induction

8

70

Sandwich
CultureRAFT™3D Cell
CultureSandwich
CultureRAFT™ 3D Cell
Culture

15.3

61.8*

4.2

33.6

60

CYP3A450

LCMS

Table 2
Fold induction of CYP activity on day 16/17. Fold induction of CYP3A4 was calculated fromthe induction and basal CYP activity for both direct and indirect methods shown in
Figure 8.
*Basal CYP levels higher in RAFT™ 3D Cell Culture

40
30
20
10
0

D4

D6

Sandwich Culture
RAFT™ 3D Cell Culture

D8Days in culture

D13

D17

Fold induction

B LCMS 3A4
40.00
35.00
30.00
25.00
20.00
15.00
10.00
5.00
0

D4

Sandwich Culture
RAFT™ 3D Cell Culture

D8Days in culture

D16

Figure 8
CYP450 activity of human hepatocytes is higher for longer culture durations in
RAFT™ 3D Cell Culture than in Sandwich Culture. Human hepatocytes were plated at
45,000–65,000 cells per well in RAFT™ 3D Cell Culture and Sandwich Culture andincubated with the inducer rifampicin (Table 1) for 72 hours. Supernatants frominduced and uninduced cells were analyzed using the P450-Glo™ Assays (Figure 8A).
In a separate experiment, the induced and uninduced cells were incubated with thesubstrate testosterone (Table 1) and LCMS was performed to quantitate the metabolite
6ß-hydroxytestosterone (Figure 8B).

Conclusions
In this White Paper, we investigated the viability and performance ofprimary human hepatocytes in 3D vs. 2D cell culture systems beyond
7 days. We demonstrate that the RAFT™ 3D Cell Culture System isa robust and easy-to-use model for the culture of primary humanhepatocytes. The collagen-based matrix of RAFT™ 3D Cell Culture
provides a more in vivo-like environment than traditional 2D culture
systems and better allows for the long-term maintenance ofhepatocyte-specific functions. The primary human hepatocytes in
RAFT™ 3D Cell Culture exhibited functions such as albumin and basal
urea production similar to the 2D cell culture. For these studies,comparable viability data were obtained for several donors ranging inage from 2 years to 53 years.
Viability determinations and CYP analysis by indirect (P450-Glo™
Kits) and direct (LCMS) activity measurements show that hepatocyte
metabolism is stabilized in RAFT™ 3D Cell Culture, enabling long-term
toxicity analysis using primary hepatocytes. In addition, the RAFT™ 3D
Cell Culture System allows for the construction of more complex livermodels with the possible inclusion of non-parenchymal cells. The RAFT™
3D Cell Culture System holds strong potential for drug testing and in
predictive toxicity studies.

Primary hepatocytes in RAFT™ 3D Cell Culture System –a model for hepatocyte toxicity studies

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9

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