Session 2

Biomedical research –

Strengths & imitations

of non-animal alternatives

In vitro liver systems:

modelling

and two-photon based

imaging

Jan G. Hengstler

IfADo-Leibniz Research

Centre

TU Dortmund

European Commission

Scientific Conference

December 6-7,

2016

Brussels

Example of a liver in vitro system

Primary human hepatocytes cultivated as spheres or cell sheets

Frey O, Hengstler JG, et al.,

Nat Commun 2014, 30;5:4250

Two-photon microscopy

Functional analysis

of intact tissues

Visualization of

mitochondria

Injection of Rhodamine

● Fluorescein-labeled bile acid analog

● Closely parallels the transport

properties of cholic acid derivatives

Transport of Cholyl-l-Lysyl-

fluorescein (CLF)

Possibilities

• Prediction of compounds that inhibit or induce

liver enzymes

• Identification of the main metabolites of a drug

• Prediction of acute toxicity

Limitations

• No microvessels (sinusoids) and therfore not

linked to circulaing imune cells

• Limitations in prediction of repeated dose

toxicity

• Limitations in recapitulating liver physiology

Liver in vitro systems In vitro

In vivo

Vartak N, …, Hengstler JG, Hepatology, 2016

Systems Modelling: Experiments with artificial cells organs

Examples:

Zeigerer A,.., Hengstler JG,…

Zerial M, Nature 2012;

485(7399):465-70.

Ghallab A, …, Hengstler JG, J Hepatol 2016; 64(4):860-71.

(Ghallab A, …, Hengstler JG,

J. Hepatol, 2016)

Integrate

functional

principles

(e.g. metabolic

pathways)

Systems modeling: The concept of tissues in silico

3D tissue

reconstruction

Compare the

result of the

simulation to

the in vivo

result

Identify missing mechanisms

and integrate them into

the model

Iterative cycles

New concept

to treat

hyper-

ammonemia

Breakdown of metabolic

detoxifying functions

of the liver (Ghallab et al.,

J. Hepatol, 2016)

Prediction of adaptive

versus adverse

responses to toxic

stress (Vartak et al.,

Hepatology, 2016)

Simulation of signal

transduction and decisionn

making in immune cells

(Cohen et al, Blood,

2013)

Modelling of cognitive

stimulation effects (Voss et al., Nat Neurosci.

2014)

Predict human

behaviour in human-

machine-interaction (Schlagkamp et al.,

HPCS, 2016)

Systems

modeling

Sub-

cellular

Cellular Organ

level

Orga-

nism

Control factors

of number and

size of

organelles (Zeigerer et al.,

Nature, 2012)

How to avoid a frustrating discussion

Please do not demonise others!

GAIA ACTION

29 November 2016

Insufficient animal testing may

cause human suffering

S-Thalidomide

Undercover in the University Hospital,

Jette Campus of the Free University of

Brussels (VUB): GAIA reveals intolerable

suffering of research animals

Recommendations for discussion

Accept that we need animal experiments in clinical and basic research

- a ban of animal experiments is no option

Define concrete strategies to reduce, replace and refine

- The pre-test principle

- Define concrete endpoints where animals are no

longer needed

- Establish in vitro systems that can be interpreted with respect

to the in vivo situation

- Systems modeling for a better planning of experiments

Replacement of a large fraction of animal experiments is an

attractive long term goal;

However, establishment of the required in vitro systems and

modelling techniques is a challenge for 1-2 generations of

scientists

Scientists under pressure: avoid isolation and unwise responses to

double standards

An example of double standards

At least 10-fold more animal are killed by rotenicides than by animal experiments

Slow and painful death by internal bleeding

No license

needed

No visible

protests

from activists

Scientists under pressure: avoid isolation and unwise responses to

double standards

Double standards of activists and politics do not release sientists

from their duty to explain the benefit of their findings to the public:

Most pharmaceuticals were discovered based on animal experiments

Modern medicine would be impossible without the knowledge gained

From animal experiments

Use all possibilities to reduce, replace and refine

Politicians, scientists and acitivists: Communicate!