EVALUATION SEMINAR ON ALTERNATIVE TO ANIMAL STUDIES PRESENTED BY: MR. UTTAM PAUL 1ST M. PHARM DEPT. OF PHARMACOLOGY FACILIATED TO: DR. SHIVALINGE GOWDA K.P. H.O.D, DEPARTMENT OF PHARMACOLOGY
Jul 16, 2015
EVALUATION SEMINAR ON ALTERNATIVE
TO ANIMAL STUDIES
PRESENTED BY:
MR. UTTAM PAUL
1ST M. PHARM
DEPT. OF PHARMACOLOGY
FACILIATED TO:
DR. SHIVALINGE GOWDA K.P.
H.O.D, DEPARTMENT OF
PHARMACOLOGY
TABLE OF CONTENTS
OVERVIEW
DEFINITION TO ALTERNATIVE TECHNIQUES
DIFFERENT TECHNIQUES TO BE USED AS
ALTERNATIVES TO ANIMAL TESTING
1) Full thickness skin model (in vitro method)
2) In sillico methods
3) Cell line technique.
4) Patch clamp method
REFERNCE
OVERVIEW
Animal usage in scientific research and testing has raised
controversy and criticism for long.
A number of legislative initiatives have been proposed from time to
time to limit animal research, or ensure proper treatment of animals.
Animal welfare groups, or reformers, opposed various forms of
animal research due to the increased use of animals for developing
drugs and safety tests for pesticides.
ALTERNATIVE TECHNIQUES: DEFINITION:
The term ‘alternative’ is used to refer to those techniques or methods
that replace the use of laboratory animals altogether, reduce the
numbers of animals required, or refine an existing procedure or
technique to minimize the level of stress endured by the animal.
However, the field of alternatives study particularly in vitro toxicology
has evolved into a respected discipline and is attracting competent and
motivated scientists around the world.
It is not possible to replace whole animal models with in vitro
systems to evaluate drug effects on major organ systems.
However, techniques can greatly reduce the number of animals
needed, and refined protocols can improve the design efficiency
and quality of studies, and lessen stress and discomfort experienced
by lab animals.
Generally instrumented animal models can be reused in major
organ systems toxicology (MOST) for studies to evaluate more than
one drug.
DIFFERENT TECHNIQUES TO BE USED AS
ALTERNATIVES TO ANIMAL TESTING
1) Full thickness skin model (in vitro method)
2) In sillico methods
3) Cell line technique.
4) Patch clamp method.
1) In-vitro methods
Cell and tissue cultures are used to test product ingredients.
Cell cultures are now also used routinely to test substances for
mutagenic properties.
Tissue cultures are additionally used to test substances for
compatibility with mucous membranes.
A test substance is applied to the Full Thickness Skin Model so that
its effect on the skin tissue can be systematically evaluated.
The substance, e.g. a cream formulation, is applied topically using a
brush. This can be done several times over a period of at least nine
days.
In this way, the effect of the substance on the cell layers in the skin
can be studied.
The standardized production of the model, in combination with its
special properties, makes it suitable for use as an in-vitro alternative
to animal testing
2. In-sillico methods
Substances with similar chemical structures often have similar
properties.
In these cases, therefore, knowledge of the properties of a few
representative substances is sufficient to be able to deduce the
properties of a series of similar substances.
By analogy, certain properties of these representative substances can
also be assumed to be properties of the other substances in the series.
The required calculations are performed using specially developed
computer programs.
Only these selected substances will then have to be tested according
to the legally prescribed test methods.
It is anticipated that combinations of such calculations will make it
possible to narrow down the number of substances to be tested.
3) Cell line technique
The term cell line refers to the propagation of culture after the
first subculture.
Once the primary culture is sub cultured, it becomes a cell line.
A cell line derived by selection or cloning is referred to as cell
strain.
Types of cell lines:
Finite cell line.
Continuous cell line.
SERIAL
NO
PROPERTIES FINITE CELL LINE
(with limited culture life
spans)
CONTINUOUS CELL LINE
(unlimited life )
1 Growth rate Slow Fast
2 Mode of growth Monolayer Suspension
3 Yield Low High
4 Transformation Normal Immortal,
Tumorigenic
5 Cloning efficiency Low High
6 Serum
requirement
High Low
7 Markers Tissue specific Chromosomal, antigenic.
APPLICATIONS OF CELL LINE
Screening of anti-cancer drugs
Cell based bioassays
To determine the cytotoxicity
In vitro screening of several drugs
Production of anti-viral vaccines
Cancer research, which require the study of uncontrolled cell
division in culture
Cell fusion technique, Genetic manipulation
Gene therapy, Recombinant DNA therapy
Biotechnology , Molecular biology……etc.
PATCH CLAMP TECHNIQUE
Patch clamp technique is a technique in electrophysiology that
allows the study of individual ion channels in cells.
The technique is used to study excitable cells such as neurons,
muscle fibers and the beta cells of the pancreas.
Use a pipette to pinch off a small region of membrane.
Provides access to:
the inside of the cell
a small region of membrane
Applications of Patch Clamp Technique:
For the evaluation of antiarrhythmic agents.
In kidney cells.
Used for isolated ventricular myocytes from Guinea pigs to
study a cardio selective inhibition of the ATP sensitive potassium
channel.
To identify multiple types of calcium channels.
To measure the effect of potassium channel openers.
Used in the molecular biology.
Voltage clamp studies on sodium channels.
Used to investigate a wide range of electrophysiological cell
properties.
Measurement of cell membrane conductance.