Download Viruses are used for gene therapy

Viruses are
used for gene
therapy
Irisa Shegani
What is gene therapy?
 Gene
therapy is an experimental
treatment that involves the introduction of
genes into existing cells to prevent or cure
diseases.
How are genes transferred into
cells?
 Genes
can be transferred to the cell by
using a “vector”.
 The vectors most commonly used in gene
therapy are viruses.
 A virus is a microscopic organism
consisting of genetic material (RNA or
DNA) sorrounded by a protein, lipid, or
glycoprotein coat.
The types of viruses used in
gene therapy are:
 Retroviruses
 Adenoviruses
 Adeno-associated
 Lentiviruses
 Poxviruses
 Herpes
viruses
viruses
Two types of delivery methods
in gene therapy
 The
first one is called ex-vivo, where the
somatic cells are:
 Removed from the patient
 Altered with gene therapy
 Injected back to the patient
Two types of delivery methods
in gene therapy
 The
second delivery method is called invivo
 The virus is used to directly inject the
patients tissue
 The most common virus for this delivery is
adenovirus
Adeno virus used in gene
therapy
A
new gene is injected into an adenovirus
vector, which is used to introduce the
modified DNA into a human cell.
Herpes virus used in gene
therapy
 It
may be used to treat a brain tumor
 When the virus gets inside the brain, it
seeks out the target tumor cells and
invades them
 The tumor starts to produce herpes
enzyme because the virus has inserted its
genetic material into the tumor cells
Advantages
 It
gives someone that is born with a
genetic disease or who develops cancern
the chance to live a normal life
 This technique has the ability to cure
many of the diseases that have effected
our society for years
Disadvantages
 The
virus may target the wrong cells
 Viruses sometimes may insert themselves
into the wrong place in the DNA
 The area that the virus targets may triger
uncontrollable growth
Ref work



Campbell,M; Farrell,S. Biochemistry, 7th edition,(pp
403)
Kirn,D; Liu,T; Source: Gene therapy;Jun 2008, Vol.15
issue 12. DOI:10.1038/gt.200872
Kostarelos,K; Singh,R; Tian,B; Source: FASEB Journal;
Sep 2008, Vol.22 Issue 9. DOI: 10.1096/FJ.08-103275